1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011, 2012 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "gimple.h"
29 #include "flags.h"
30 #include "expr.h"
31 #include "optabs.h"
32 #include "libfuncs.h"
33 #include "function.h"
34 #include "regs.h"
35 #include "diagnostic-core.h"
36 #include "output.h"
37 #include "tm_p.h"
38 #include "timevar.h"
39 #include "sbitmap.h"
40 #include "langhooks.h"
41 #include "target.h"
42 #include "cgraph.h"
43 #include "except.h"
44 #include "dbgcnt.h"
45 #include "tree-flow.h"
46
47 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
49
50 /* Data structure and subroutines used within expand_call. */
51
52 struct arg_data
53 {
54 /* Tree node for this argument. */
55 tree tree_value;
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
59 rtx value;
60 /* Initially-compute RTL value for argument; only for const functions. */
61 rtx initial_value;
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 PARALLEL if the arg is to be copied into multiple non-contiguous
64 registers. */
65 rtx reg;
66 /* Register to pass this argument in when generating tail call sequence.
67 This is not the same register as for normal calls on machines with
68 register windows. */
69 rtx tail_call_reg;
70 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
71 form for emit_group_move. */
72 rtx parallel_value;
73 /* If REG was promoted from the actual mode of the argument expression,
74 indicates whether the promotion is sign- or zero-extended. */
75 int unsignedp;
76 /* Number of bytes to put in registers. 0 means put the whole arg
77 in registers. Also 0 if not passed in registers. */
78 int partial;
79 /* Nonzero if argument must be passed on stack.
80 Note that some arguments may be passed on the stack
81 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
82 pass_on_stack identifies arguments that *cannot* go in registers. */
83 int pass_on_stack;
84 /* Some fields packaged up for locate_and_pad_parm. */
85 struct locate_and_pad_arg_data locate;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
88 rtx stack;
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
92 rtx stack_slot;
93 /* Place that this stack area has been saved, if needed. */
94 rtx save_area;
95 /* If an argument's alignment does not permit direct copying into registers,
96 copy in smaller-sized pieces into pseudos. These are stored in a
97 block pointed to by this field. The next field says how many
98 word-sized pseudos we made. */
99 rtx *aligned_regs;
100 int n_aligned_regs;
101 };
102
103 /* A vector of one char per byte of stack space. A byte if nonzero if
104 the corresponding stack location has been used.
105 This vector is used to prevent a function call within an argument from
106 clobbering any stack already set up. */
107 static char *stack_usage_map;
108
109 /* Size of STACK_USAGE_MAP. */
110 static int highest_outgoing_arg_in_use;
111
112 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
113 stack location's tail call argument has been already stored into the stack.
114 This bitmap is used to prevent sibling call optimization if function tries
115 to use parent's incoming argument slots when they have been already
116 overwritten with tail call arguments. */
117 static sbitmap stored_args_map;
118
119 /* stack_arg_under_construction is nonzero when an argument may be
120 initialized with a constructor call (including a C function that
121 returns a BLKmode struct) and expand_call must take special action
122 to make sure the object being constructed does not overlap the
123 argument list for the constructor call. */
124 static int stack_arg_under_construction;
125
126 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
127 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
128 cumulative_args_t);
129 static void precompute_register_parameters (int, struct arg_data *, int *);
130 static int store_one_arg (struct arg_data *, rtx, int, int, int);
131 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
132 static int finalize_must_preallocate (int, int, struct arg_data *,
133 struct args_size *);
134 static void precompute_arguments (int, struct arg_data *);
135 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
136 static void initialize_argument_information (int, struct arg_data *,
137 struct args_size *, int,
138 tree, tree,
139 tree, tree, cumulative_args_t, int,
140 rtx *, int *, int *, int *,
141 bool *, bool);
142 static void compute_argument_addresses (struct arg_data *, rtx, int);
143 static rtx rtx_for_function_call (tree, tree);
144 static void load_register_parameters (struct arg_data *, int, rtx *, int,
145 int, int *);
146 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
147 enum machine_mode, int, va_list);
148 static int special_function_p (const_tree, int);
149 static int check_sibcall_argument_overlap_1 (rtx);
150 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
151
152 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
153 unsigned int);
154 static tree split_complex_types (tree);
155
156 #ifdef REG_PARM_STACK_SPACE
157 static rtx save_fixed_argument_area (int, rtx, int *, int *);
158 static void restore_fixed_argument_area (rtx, rtx, int, int);
159 #endif
160
161 /* Force FUNEXP into a form suitable for the address of a CALL,
162 and return that as an rtx. Also load the static chain register
163 if FNDECL is a nested function.
164
165 CALL_FUSAGE points to a variable holding the prospective
166 CALL_INSN_FUNCTION_USAGE information. */
167
168 rtx
prepare_call_address(tree fndecl,rtx funexp,rtx static_chain_value,rtx * call_fusage,int reg_parm_seen,int sibcallp)169 prepare_call_address (tree fndecl, rtx funexp, rtx static_chain_value,
170 rtx *call_fusage, int reg_parm_seen, int sibcallp)
171 {
172 /* Make a valid memory address and copy constants through pseudo-regs,
173 but not for a constant address if -fno-function-cse. */
174 if (GET_CODE (funexp) != SYMBOL_REF)
175 /* If we are using registers for parameters, force the
176 function address into a register now. */
177 funexp = ((reg_parm_seen
178 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
179 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
180 : memory_address (FUNCTION_MODE, funexp));
181 else if (! sibcallp)
182 {
183 #ifndef NO_FUNCTION_CSE
184 if (optimize && ! flag_no_function_cse)
185 funexp = force_reg (Pmode, funexp);
186 #endif
187 }
188
189 if (static_chain_value != 0)
190 {
191 rtx chain;
192
193 gcc_assert (fndecl);
194 chain = targetm.calls.static_chain (fndecl, false);
195 static_chain_value = convert_memory_address (Pmode, static_chain_value);
196
197 emit_move_insn (chain, static_chain_value);
198 if (REG_P (chain))
199 use_reg (call_fusage, chain);
200 }
201
202 return funexp;
203 }
204
205 /* Generate instructions to call function FUNEXP,
206 and optionally pop the results.
207 The CALL_INSN is the first insn generated.
208
209 FNDECL is the declaration node of the function. This is given to the
210 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
211 its own args.
212
213 FUNTYPE is the data type of the function. This is given to the hook
214 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
215 own args. We used to allow an identifier for library functions, but
216 that doesn't work when the return type is an aggregate type and the
217 calling convention says that the pointer to this aggregate is to be
218 popped by the callee.
219
220 STACK_SIZE is the number of bytes of arguments on the stack,
221 ROUNDED_STACK_SIZE is that number rounded up to
222 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
223 both to put into the call insn and to generate explicit popping
224 code if necessary.
225
226 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
227 It is zero if this call doesn't want a structure value.
228
229 NEXT_ARG_REG is the rtx that results from executing
230 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
231 just after all the args have had their registers assigned.
232 This could be whatever you like, but normally it is the first
233 arg-register beyond those used for args in this call,
234 or 0 if all the arg-registers are used in this call.
235 It is passed on to `gen_call' so you can put this info in the call insn.
236
237 VALREG is a hard register in which a value is returned,
238 or 0 if the call does not return a value.
239
240 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
241 the args to this call were processed.
242 We restore `inhibit_defer_pop' to that value.
243
244 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
245 denote registers used by the called function. */
246
247 static void
emit_call_1(rtx funexp,tree fntree ATTRIBUTE_UNUSED,tree fndecl ATTRIBUTE_UNUSED,tree funtype ATTRIBUTE_UNUSED,HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,HOST_WIDE_INT rounded_stack_size,HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,rtx next_arg_reg ATTRIBUTE_UNUSED,rtx valreg,int old_inhibit_defer_pop,rtx call_fusage,int ecf_flags,cumulative_args_t args_so_far ATTRIBUTE_UNUSED)248 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
249 tree funtype ATTRIBUTE_UNUSED,
250 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
251 HOST_WIDE_INT rounded_stack_size,
252 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
253 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
254 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
255 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
256 {
257 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
258 rtx call_insn, call, funmem;
259 int already_popped = 0;
260 HOST_WIDE_INT n_popped
261 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
262
263 #ifdef CALL_POPS_ARGS
264 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
265 #endif
266
267 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
268 and we don't want to load it into a register as an optimization,
269 because prepare_call_address already did it if it should be done. */
270 if (GET_CODE (funexp) != SYMBOL_REF)
271 funexp = memory_address (FUNCTION_MODE, funexp);
272
273 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
274 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
275 {
276 tree t = fndecl;
277
278 /* Although a built-in FUNCTION_DECL and its non-__builtin
279 counterpart compare equal and get a shared mem_attrs, they
280 produce different dump output in compare-debug compilations,
281 if an entry gets garbage collected in one compilation, then
282 adds a different (but equivalent) entry, while the other
283 doesn't run the garbage collector at the same spot and then
284 shares the mem_attr with the equivalent entry. */
285 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
286 {
287 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
288 if (t2)
289 t = t2;
290 }
291
292 set_mem_expr (funmem, t);
293 }
294 else if (fntree)
295 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
296
297 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
298 if ((ecf_flags & ECF_SIBCALL)
299 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
300 && (n_popped > 0 || stack_size == 0))
301 {
302 rtx n_pop = GEN_INT (n_popped);
303 rtx pat;
304
305 /* If this subroutine pops its own args, record that in the call insn
306 if possible, for the sake of frame pointer elimination. */
307
308 if (valreg)
309 pat = GEN_SIBCALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
310 next_arg_reg, n_pop);
311 else
312 pat = GEN_SIBCALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
313 n_pop);
314
315 emit_call_insn (pat);
316 already_popped = 1;
317 }
318 else
319 #endif
320
321 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
322 /* If the target has "call" or "call_value" insns, then prefer them
323 if no arguments are actually popped. If the target does not have
324 "call" or "call_value" insns, then we must use the popping versions
325 even if the call has no arguments to pop. */
326 #if defined (HAVE_call) && defined (HAVE_call_value)
327 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
328 && n_popped > 0)
329 #else
330 if (HAVE_call_pop && HAVE_call_value_pop)
331 #endif
332 {
333 rtx n_pop = GEN_INT (n_popped);
334 rtx pat;
335
336 /* If this subroutine pops its own args, record that in the call insn
337 if possible, for the sake of frame pointer elimination. */
338
339 if (valreg)
340 pat = GEN_CALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
341 next_arg_reg, n_pop);
342 else
343 pat = GEN_CALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
344 n_pop);
345
346 emit_call_insn (pat);
347 already_popped = 1;
348 }
349 else
350 #endif
351
352 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
353 if ((ecf_flags & ECF_SIBCALL)
354 && HAVE_sibcall && HAVE_sibcall_value)
355 {
356 if (valreg)
357 emit_call_insn (GEN_SIBCALL_VALUE (valreg, funmem,
358 rounded_stack_size_rtx,
359 next_arg_reg, NULL_RTX));
360 else
361 emit_call_insn (GEN_SIBCALL (funmem, rounded_stack_size_rtx,
362 next_arg_reg,
363 GEN_INT (struct_value_size)));
364 }
365 else
366 #endif
367
368 #if defined (HAVE_call) && defined (HAVE_call_value)
369 if (HAVE_call && HAVE_call_value)
370 {
371 if (valreg)
372 emit_call_insn (GEN_CALL_VALUE (valreg, funmem, rounded_stack_size_rtx,
373 next_arg_reg, NULL_RTX));
374 else
375 emit_call_insn (GEN_CALL (funmem, rounded_stack_size_rtx, next_arg_reg,
376 GEN_INT (struct_value_size)));
377 }
378 else
379 #endif
380 gcc_unreachable ();
381
382 /* Find the call we just emitted. */
383 call_insn = last_call_insn ();
384
385 /* Some target create a fresh MEM instead of reusing the one provided
386 above. Set its MEM_EXPR. */
387 call = PATTERN (call_insn);
388 if (GET_CODE (call) == PARALLEL)
389 call = XVECEXP (call, 0, 0);
390 if (GET_CODE (call) == SET)
391 call = SET_SRC (call);
392 if (GET_CODE (call) == CALL
393 && MEM_P (XEXP (call, 0))
394 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
395 && MEM_EXPR (funmem) != NULL_TREE)
396 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
397
398 /* Put the register usage information there. */
399 add_function_usage_to (call_insn, call_fusage);
400
401 /* If this is a const call, then set the insn's unchanging bit. */
402 if (ecf_flags & ECF_CONST)
403 RTL_CONST_CALL_P (call_insn) = 1;
404
405 /* If this is a pure call, then set the insn's unchanging bit. */
406 if (ecf_flags & ECF_PURE)
407 RTL_PURE_CALL_P (call_insn) = 1;
408
409 /* If this is a const call, then set the insn's unchanging bit. */
410 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
411 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
412
413 /* Create a nothrow REG_EH_REGION note, if needed. */
414 make_reg_eh_region_note (call_insn, ecf_flags, 0);
415
416 if (ecf_flags & ECF_NORETURN)
417 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
418
419 if (ecf_flags & ECF_RETURNS_TWICE)
420 {
421 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
422 cfun->calls_setjmp = 1;
423 }
424
425 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
426
427 /* Restore this now, so that we do defer pops for this call's args
428 if the context of the call as a whole permits. */
429 inhibit_defer_pop = old_inhibit_defer_pop;
430
431 if (n_popped > 0)
432 {
433 if (!already_popped)
434 CALL_INSN_FUNCTION_USAGE (call_insn)
435 = gen_rtx_EXPR_LIST (VOIDmode,
436 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
437 CALL_INSN_FUNCTION_USAGE (call_insn));
438 rounded_stack_size -= n_popped;
439 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
440 stack_pointer_delta -= n_popped;
441
442 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
443
444 /* If popup is needed, stack realign must use DRAP */
445 if (SUPPORTS_STACK_ALIGNMENT)
446 crtl->need_drap = true;
447 }
448 /* For noreturn calls when not accumulating outgoing args force
449 REG_ARGS_SIZE note to prevent crossjumping of calls with different
450 args sizes. */
451 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
452 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
453
454 if (!ACCUMULATE_OUTGOING_ARGS)
455 {
456 /* If returning from the subroutine does not automatically pop the args,
457 we need an instruction to pop them sooner or later.
458 Perhaps do it now; perhaps just record how much space to pop later.
459
460 If returning from the subroutine does pop the args, indicate that the
461 stack pointer will be changed. */
462
463 if (rounded_stack_size != 0)
464 {
465 if (ecf_flags & ECF_NORETURN)
466 /* Just pretend we did the pop. */
467 stack_pointer_delta -= rounded_stack_size;
468 else if (flag_defer_pop && inhibit_defer_pop == 0
469 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
470 pending_stack_adjust += rounded_stack_size;
471 else
472 adjust_stack (rounded_stack_size_rtx);
473 }
474 }
475 /* When we accumulate outgoing args, we must avoid any stack manipulations.
476 Restore the stack pointer to its original value now. Usually
477 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
478 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
479 popping variants of functions exist as well.
480
481 ??? We may optimize similar to defer_pop above, but it is
482 probably not worthwhile.
483
484 ??? It will be worthwhile to enable combine_stack_adjustments even for
485 such machines. */
486 else if (n_popped)
487 anti_adjust_stack (GEN_INT (n_popped));
488 }
489
490 /* Determine if the function identified by NAME and FNDECL is one with
491 special properties we wish to know about.
492
493 For example, if the function might return more than one time (setjmp), then
494 set RETURNS_TWICE to a nonzero value.
495
496 Similarly set NORETURN if the function is in the longjmp family.
497
498 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
499 space from the stack such as alloca. */
500
501 static int
special_function_p(const_tree fndecl,int flags)502 special_function_p (const_tree fndecl, int flags)
503 {
504 if (fndecl && DECL_NAME (fndecl)
505 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
506 /* Exclude functions not at the file scope, or not `extern',
507 since they are not the magic functions we would otherwise
508 think they are.
509 FIXME: this should be handled with attributes, not with this
510 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
511 because you can declare fork() inside a function if you
512 wish. */
513 && (DECL_CONTEXT (fndecl) == NULL_TREE
514 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
515 && TREE_PUBLIC (fndecl))
516 {
517 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
518 const char *tname = name;
519
520 /* We assume that alloca will always be called by name. It
521 makes no sense to pass it as a pointer-to-function to
522 anything that does not understand its behavior. */
523 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
524 && name[0] == 'a'
525 && ! strcmp (name, "alloca"))
526 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
527 && name[0] == '_'
528 && ! strcmp (name, "__builtin_alloca"))))
529 flags |= ECF_MAY_BE_ALLOCA;
530
531 /* Disregard prefix _, __, __x or __builtin_. */
532 if (name[0] == '_')
533 {
534 if (name[1] == '_'
535 && name[2] == 'b'
536 && !strncmp (name + 3, "uiltin_", 7))
537 tname += 10;
538 else if (name[1] == '_' && name[2] == 'x')
539 tname += 3;
540 else if (name[1] == '_')
541 tname += 2;
542 else
543 tname += 1;
544 }
545
546 if (tname[0] == 's')
547 {
548 if ((tname[1] == 'e'
549 && (! strcmp (tname, "setjmp")
550 || ! strcmp (tname, "setjmp_syscall")))
551 || (tname[1] == 'i'
552 && ! strcmp (tname, "sigsetjmp"))
553 || (tname[1] == 'a'
554 && ! strcmp (tname, "savectx")))
555 flags |= ECF_RETURNS_TWICE;
556
557 if (tname[1] == 'i'
558 && ! strcmp (tname, "siglongjmp"))
559 flags |= ECF_NORETURN;
560 }
561 else if ((tname[0] == 'q' && tname[1] == 's'
562 && ! strcmp (tname, "qsetjmp"))
563 || (tname[0] == 'v' && tname[1] == 'f'
564 && ! strcmp (tname, "vfork"))
565 || (tname[0] == 'g' && tname[1] == 'e'
566 && !strcmp (tname, "getcontext")))
567 flags |= ECF_RETURNS_TWICE;
568
569 else if (tname[0] == 'l' && tname[1] == 'o'
570 && ! strcmp (tname, "longjmp"))
571 flags |= ECF_NORETURN;
572 }
573
574 return flags;
575 }
576
577 /* Return nonzero when FNDECL represents a call to setjmp. */
578
579 int
setjmp_call_p(const_tree fndecl)580 setjmp_call_p (const_tree fndecl)
581 {
582 if (DECL_IS_RETURNS_TWICE (fndecl))
583 return ECF_RETURNS_TWICE;
584 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
585 }
586
587
588 /* Return true if STMT is an alloca call. */
589
590 bool
gimple_alloca_call_p(const_gimple stmt)591 gimple_alloca_call_p (const_gimple stmt)
592 {
593 tree fndecl;
594
595 if (!is_gimple_call (stmt))
596 return false;
597
598 fndecl = gimple_call_fndecl (stmt);
599 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
600 return true;
601
602 return false;
603 }
604
605 /* Return true when exp contains alloca call. */
606
607 bool
alloca_call_p(const_tree exp)608 alloca_call_p (const_tree exp)
609 {
610 if (TREE_CODE (exp) == CALL_EXPR
611 && TREE_CODE (CALL_EXPR_FN (exp)) == ADDR_EXPR
612 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp), 0)) == FUNCTION_DECL)
613 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp), 0), 0)
614 & ECF_MAY_BE_ALLOCA))
615 return true;
616 return false;
617 }
618
619 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
620 function. Return FALSE otherwise. */
621
622 static bool
is_tm_builtin(const_tree fndecl)623 is_tm_builtin (const_tree fndecl)
624 {
625 if (fndecl == NULL)
626 return false;
627
628 if (decl_is_tm_clone (fndecl))
629 return true;
630
631 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
632 {
633 switch (DECL_FUNCTION_CODE (fndecl))
634 {
635 case BUILT_IN_TM_COMMIT:
636 case BUILT_IN_TM_COMMIT_EH:
637 case BUILT_IN_TM_ABORT:
638 case BUILT_IN_TM_IRREVOCABLE:
639 case BUILT_IN_TM_GETTMCLONE_IRR:
640 case BUILT_IN_TM_MEMCPY:
641 case BUILT_IN_TM_MEMMOVE:
642 case BUILT_IN_TM_MEMSET:
643 CASE_BUILT_IN_TM_STORE (1):
644 CASE_BUILT_IN_TM_STORE (2):
645 CASE_BUILT_IN_TM_STORE (4):
646 CASE_BUILT_IN_TM_STORE (8):
647 CASE_BUILT_IN_TM_STORE (FLOAT):
648 CASE_BUILT_IN_TM_STORE (DOUBLE):
649 CASE_BUILT_IN_TM_STORE (LDOUBLE):
650 CASE_BUILT_IN_TM_STORE (M64):
651 CASE_BUILT_IN_TM_STORE (M128):
652 CASE_BUILT_IN_TM_STORE (M256):
653 CASE_BUILT_IN_TM_LOAD (1):
654 CASE_BUILT_IN_TM_LOAD (2):
655 CASE_BUILT_IN_TM_LOAD (4):
656 CASE_BUILT_IN_TM_LOAD (8):
657 CASE_BUILT_IN_TM_LOAD (FLOAT):
658 CASE_BUILT_IN_TM_LOAD (DOUBLE):
659 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
660 CASE_BUILT_IN_TM_LOAD (M64):
661 CASE_BUILT_IN_TM_LOAD (M128):
662 CASE_BUILT_IN_TM_LOAD (M256):
663 case BUILT_IN_TM_LOG:
664 case BUILT_IN_TM_LOG_1:
665 case BUILT_IN_TM_LOG_2:
666 case BUILT_IN_TM_LOG_4:
667 case BUILT_IN_TM_LOG_8:
668 case BUILT_IN_TM_LOG_FLOAT:
669 case BUILT_IN_TM_LOG_DOUBLE:
670 case BUILT_IN_TM_LOG_LDOUBLE:
671 case BUILT_IN_TM_LOG_M64:
672 case BUILT_IN_TM_LOG_M128:
673 case BUILT_IN_TM_LOG_M256:
674 return true;
675 default:
676 break;
677 }
678 }
679 return false;
680 }
681
682 /* Detect flags (function attributes) from the function decl or type node. */
683
684 int
flags_from_decl_or_type(const_tree exp)685 flags_from_decl_or_type (const_tree exp)
686 {
687 int flags = 0;
688
689 if (DECL_P (exp))
690 {
691 /* The function exp may have the `malloc' attribute. */
692 if (DECL_IS_MALLOC (exp))
693 flags |= ECF_MALLOC;
694
695 /* The function exp may have the `returns_twice' attribute. */
696 if (DECL_IS_RETURNS_TWICE (exp))
697 flags |= ECF_RETURNS_TWICE;
698
699 /* Process the pure and const attributes. */
700 if (TREE_READONLY (exp))
701 flags |= ECF_CONST;
702 if (DECL_PURE_P (exp))
703 flags |= ECF_PURE;
704 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
705 flags |= ECF_LOOPING_CONST_OR_PURE;
706
707 if (DECL_IS_NOVOPS (exp))
708 flags |= ECF_NOVOPS;
709 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
710 flags |= ECF_LEAF;
711
712 if (TREE_NOTHROW (exp))
713 flags |= ECF_NOTHROW;
714
715 if (flag_tm)
716 {
717 if (is_tm_builtin (exp))
718 flags |= ECF_TM_BUILTIN;
719 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
720 || lookup_attribute ("transaction_pure",
721 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
722 flags |= ECF_TM_PURE;
723 }
724
725 flags = special_function_p (exp, flags);
726 }
727 else if (TYPE_P (exp))
728 {
729 if (TYPE_READONLY (exp))
730 flags |= ECF_CONST;
731
732 if (flag_tm
733 && ((flags & ECF_CONST) != 0
734 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
735 flags |= ECF_TM_PURE;
736 }
737
738 if (TREE_THIS_VOLATILE (exp))
739 {
740 flags |= ECF_NORETURN;
741 if (flags & (ECF_CONST|ECF_PURE))
742 flags |= ECF_LOOPING_CONST_OR_PURE;
743 }
744
745 return flags;
746 }
747
748 /* Detect flags from a CALL_EXPR. */
749
750 int
call_expr_flags(const_tree t)751 call_expr_flags (const_tree t)
752 {
753 int flags;
754 tree decl = get_callee_fndecl (t);
755
756 if (decl)
757 flags = flags_from_decl_or_type (decl);
758 else
759 {
760 t = TREE_TYPE (CALL_EXPR_FN (t));
761 if (t && TREE_CODE (t) == POINTER_TYPE)
762 flags = flags_from_decl_or_type (TREE_TYPE (t));
763 else
764 flags = 0;
765 }
766
767 return flags;
768 }
769
770 /* Precompute all register parameters as described by ARGS, storing values
771 into fields within the ARGS array.
772
773 NUM_ACTUALS indicates the total number elements in the ARGS array.
774
775 Set REG_PARM_SEEN if we encounter a register parameter. */
776
777 static void
precompute_register_parameters(int num_actuals,struct arg_data * args,int * reg_parm_seen)778 precompute_register_parameters (int num_actuals, struct arg_data *args,
779 int *reg_parm_seen)
780 {
781 int i;
782
783 *reg_parm_seen = 0;
784
785 for (i = 0; i < num_actuals; i++)
786 if (args[i].reg != 0 && ! args[i].pass_on_stack)
787 {
788 *reg_parm_seen = 1;
789
790 if (args[i].value == 0)
791 {
792 push_temp_slots ();
793 args[i].value = expand_normal (args[i].tree_value);
794 preserve_temp_slots (args[i].value);
795 pop_temp_slots ();
796 }
797
798 /* If we are to promote the function arg to a wider mode,
799 do it now. */
800
801 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
802 args[i].value
803 = convert_modes (args[i].mode,
804 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
805 args[i].value, args[i].unsignedp);
806
807 /* If the value is a non-legitimate constant, force it into a
808 pseudo now. TLS symbols sometimes need a call to resolve. */
809 if (CONSTANT_P (args[i].value)
810 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
811 args[i].value = force_reg (args[i].mode, args[i].value);
812
813 /* If we're going to have to load the value by parts, pull the
814 parts into pseudos. The part extraction process can involve
815 non-trivial computation. */
816 if (GET_CODE (args[i].reg) == PARALLEL)
817 {
818 tree type = TREE_TYPE (args[i].tree_value);
819 args[i].parallel_value
820 = emit_group_load_into_temps (args[i].reg, args[i].value,
821 type, int_size_in_bytes (type));
822 }
823
824 /* If the value is expensive, and we are inside an appropriately
825 short loop, put the value into a pseudo and then put the pseudo
826 into the hard reg.
827
828 For small register classes, also do this if this call uses
829 register parameters. This is to avoid reload conflicts while
830 loading the parameters registers. */
831
832 else if ((! (REG_P (args[i].value)
833 || (GET_CODE (args[i].value) == SUBREG
834 && REG_P (SUBREG_REG (args[i].value)))))
835 && args[i].mode != BLKmode
836 && set_src_cost (args[i].value, optimize_insn_for_speed_p ())
837 > COSTS_N_INSNS (1)
838 && ((*reg_parm_seen
839 && targetm.small_register_classes_for_mode_p (args[i].mode))
840 || optimize))
841 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
842 }
843 }
844
845 #ifdef REG_PARM_STACK_SPACE
846
847 /* The argument list is the property of the called routine and it
848 may clobber it. If the fixed area has been used for previous
849 parameters, we must save and restore it. */
850
851 static rtx
save_fixed_argument_area(int reg_parm_stack_space,rtx argblock,int * low_to_save,int * high_to_save)852 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
853 {
854 int low;
855 int high;
856
857 /* Compute the boundary of the area that needs to be saved, if any. */
858 high = reg_parm_stack_space;
859 #ifdef ARGS_GROW_DOWNWARD
860 high += 1;
861 #endif
862 if (high > highest_outgoing_arg_in_use)
863 high = highest_outgoing_arg_in_use;
864
865 for (low = 0; low < high; low++)
866 if (stack_usage_map[low] != 0)
867 {
868 int num_to_save;
869 enum machine_mode save_mode;
870 int delta;
871 rtx stack_area;
872 rtx save_area;
873
874 while (stack_usage_map[--high] == 0)
875 ;
876
877 *low_to_save = low;
878 *high_to_save = high;
879
880 num_to_save = high - low + 1;
881 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
882
883 /* If we don't have the required alignment, must do this
884 in BLKmode. */
885 if ((low & (MIN (GET_MODE_SIZE (save_mode),
886 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
887 save_mode = BLKmode;
888
889 #ifdef ARGS_GROW_DOWNWARD
890 delta = -high;
891 #else
892 delta = low;
893 #endif
894 stack_area = gen_rtx_MEM (save_mode,
895 memory_address (save_mode,
896 plus_constant (argblock,
897 delta)));
898
899 set_mem_align (stack_area, PARM_BOUNDARY);
900 if (save_mode == BLKmode)
901 {
902 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
903 emit_block_move (validize_mem (save_area), stack_area,
904 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
905 }
906 else
907 {
908 save_area = gen_reg_rtx (save_mode);
909 emit_move_insn (save_area, stack_area);
910 }
911
912 return save_area;
913 }
914
915 return NULL_RTX;
916 }
917
918 static void
restore_fixed_argument_area(rtx save_area,rtx argblock,int high_to_save,int low_to_save)919 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
920 {
921 enum machine_mode save_mode = GET_MODE (save_area);
922 int delta;
923 rtx stack_area;
924
925 #ifdef ARGS_GROW_DOWNWARD
926 delta = -high_to_save;
927 #else
928 delta = low_to_save;
929 #endif
930 stack_area = gen_rtx_MEM (save_mode,
931 memory_address (save_mode,
932 plus_constant (argblock, delta)));
933 set_mem_align (stack_area, PARM_BOUNDARY);
934
935 if (save_mode != BLKmode)
936 emit_move_insn (stack_area, save_area);
937 else
938 emit_block_move (stack_area, validize_mem (save_area),
939 GEN_INT (high_to_save - low_to_save + 1),
940 BLOCK_OP_CALL_PARM);
941 }
942 #endif /* REG_PARM_STACK_SPACE */
943
944 /* If any elements in ARGS refer to parameters that are to be passed in
945 registers, but not in memory, and whose alignment does not permit a
946 direct copy into registers. Copy the values into a group of pseudos
947 which we will later copy into the appropriate hard registers.
948
949 Pseudos for each unaligned argument will be stored into the array
950 args[argnum].aligned_regs. The caller is responsible for deallocating
951 the aligned_regs array if it is nonzero. */
952
953 static void
store_unaligned_arguments_into_pseudos(struct arg_data * args,int num_actuals)954 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
955 {
956 int i, j;
957
958 for (i = 0; i < num_actuals; i++)
959 if (args[i].reg != 0 && ! args[i].pass_on_stack
960 && args[i].mode == BLKmode
961 && MEM_P (args[i].value)
962 && (MEM_ALIGN (args[i].value)
963 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
964 {
965 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
966 int endian_correction = 0;
967
968 if (args[i].partial)
969 {
970 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
971 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
972 }
973 else
974 {
975 args[i].n_aligned_regs
976 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
977 }
978
979 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
980
981 /* Structures smaller than a word are normally aligned to the
982 least significant byte. On a BYTES_BIG_ENDIAN machine,
983 this means we must skip the empty high order bytes when
984 calculating the bit offset. */
985 if (bytes < UNITS_PER_WORD
986 #ifdef BLOCK_REG_PADDING
987 && (BLOCK_REG_PADDING (args[i].mode,
988 TREE_TYPE (args[i].tree_value), 1)
989 == downward)
990 #else
991 && BYTES_BIG_ENDIAN
992 #endif
993 )
994 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
995
996 for (j = 0; j < args[i].n_aligned_regs; j++)
997 {
998 rtx reg = gen_reg_rtx (word_mode);
999 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1000 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1001
1002 args[i].aligned_regs[j] = reg;
1003 word = extract_bit_field (word, bitsize, 0, 1, false, NULL_RTX,
1004 word_mode, word_mode);
1005
1006 /* There is no need to restrict this code to loading items
1007 in TYPE_ALIGN sized hunks. The bitfield instructions can
1008 load up entire word sized registers efficiently.
1009
1010 ??? This may not be needed anymore.
1011 We use to emit a clobber here but that doesn't let later
1012 passes optimize the instructions we emit. By storing 0 into
1013 the register later passes know the first AND to zero out the
1014 bitfield being set in the register is unnecessary. The store
1015 of 0 will be deleted as will at least the first AND. */
1016
1017 emit_move_insn (reg, const0_rtx);
1018
1019 bytes -= bitsize / BITS_PER_UNIT;
1020 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1021 word_mode, word);
1022 }
1023 }
1024 }
1025
1026 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1027 CALL_EXPR EXP.
1028
1029 NUM_ACTUALS is the total number of parameters.
1030
1031 N_NAMED_ARGS is the total number of named arguments.
1032
1033 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1034 value, or null.
1035
1036 FNDECL is the tree code for the target of this call (if known)
1037
1038 ARGS_SO_FAR holds state needed by the target to know where to place
1039 the next argument.
1040
1041 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1042 for arguments which are passed in registers.
1043
1044 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1045 and may be modified by this routine.
1046
1047 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1048 flags which may may be modified by this routine.
1049
1050 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1051 that requires allocation of stack space.
1052
1053 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1054 the thunked-to function. */
1055
1056 static void
initialize_argument_information(int num_actuals ATTRIBUTE_UNUSED,struct arg_data * args,struct args_size * args_size,int n_named_args ATTRIBUTE_UNUSED,tree exp,tree struct_value_addr_value,tree fndecl,tree fntype,cumulative_args_t args_so_far,int reg_parm_stack_space,rtx * old_stack_level,int * old_pending_adj,int * must_preallocate,int * ecf_flags,bool * may_tailcall,bool call_from_thunk_p)1057 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1058 struct arg_data *args,
1059 struct args_size *args_size,
1060 int n_named_args ATTRIBUTE_UNUSED,
1061 tree exp, tree struct_value_addr_value,
1062 tree fndecl, tree fntype,
1063 cumulative_args_t args_so_far,
1064 int reg_parm_stack_space,
1065 rtx *old_stack_level, int *old_pending_adj,
1066 int *must_preallocate, int *ecf_flags,
1067 bool *may_tailcall, bool call_from_thunk_p)
1068 {
1069 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1070 location_t loc = EXPR_LOCATION (exp);
1071 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1072 int inc;
1073
1074 /* Count arg position in order args appear. */
1075 int argpos;
1076
1077 int i;
1078
1079 args_size->constant = 0;
1080 args_size->var = 0;
1081
1082 /* In this loop, we consider args in the order they are written.
1083 We fill up ARGS from the front or from the back if necessary
1084 so that in any case the first arg to be pushed ends up at the front. */
1085
1086 if (PUSH_ARGS_REVERSED)
1087 {
1088 i = num_actuals - 1, inc = -1;
1089 /* In this case, must reverse order of args
1090 so that we compute and push the last arg first. */
1091 }
1092 else
1093 {
1094 i = 0, inc = 1;
1095 }
1096
1097 /* First fill in the actual arguments in the ARGS array, splitting
1098 complex arguments if necessary. */
1099 {
1100 int j = i;
1101 call_expr_arg_iterator iter;
1102 tree arg;
1103
1104 if (struct_value_addr_value)
1105 {
1106 args[j].tree_value = struct_value_addr_value;
1107 j += inc;
1108 }
1109 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1110 {
1111 tree argtype = TREE_TYPE (arg);
1112 if (targetm.calls.split_complex_arg
1113 && argtype
1114 && TREE_CODE (argtype) == COMPLEX_TYPE
1115 && targetm.calls.split_complex_arg (argtype))
1116 {
1117 tree subtype = TREE_TYPE (argtype);
1118 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1119 j += inc;
1120 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1121 }
1122 else
1123 args[j].tree_value = arg;
1124 j += inc;
1125 }
1126 }
1127
1128 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1129 for (argpos = 0; argpos < num_actuals; i += inc, argpos++)
1130 {
1131 tree type = TREE_TYPE (args[i].tree_value);
1132 int unsignedp;
1133 enum machine_mode mode;
1134
1135 /* Replace erroneous argument with constant zero. */
1136 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1137 args[i].tree_value = integer_zero_node, type = integer_type_node;
1138
1139 /* If TYPE is a transparent union or record, pass things the way
1140 we would pass the first field of the union or record. We have
1141 already verified that the modes are the same. */
1142 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1143 && TYPE_TRANSPARENT_AGGR (type))
1144 type = TREE_TYPE (first_field (type));
1145
1146 /* Decide where to pass this arg.
1147
1148 args[i].reg is nonzero if all or part is passed in registers.
1149
1150 args[i].partial is nonzero if part but not all is passed in registers,
1151 and the exact value says how many bytes are passed in registers.
1152
1153 args[i].pass_on_stack is nonzero if the argument must at least be
1154 computed on the stack. It may then be loaded back into registers
1155 if args[i].reg is nonzero.
1156
1157 These decisions are driven by the FUNCTION_... macros and must agree
1158 with those made by function.c. */
1159
1160 /* See if this argument should be passed by invisible reference. */
1161 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1162 type, argpos < n_named_args))
1163 {
1164 bool callee_copies;
1165 tree base = NULL_TREE;
1166
1167 callee_copies
1168 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1169 type, argpos < n_named_args);
1170
1171 /* If we're compiling a thunk, pass through invisible references
1172 instead of making a copy. */
1173 if (call_from_thunk_p
1174 || (callee_copies
1175 && !TREE_ADDRESSABLE (type)
1176 && (base = get_base_address (args[i].tree_value))
1177 && TREE_CODE (base) != SSA_NAME
1178 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1179 {
1180 mark_addressable (args[i].tree_value);
1181
1182 /* We can't use sibcalls if a callee-copied argument is
1183 stored in the current function's frame. */
1184 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1185 *may_tailcall = false;
1186
1187 args[i].tree_value = build_fold_addr_expr_loc (loc,
1188 args[i].tree_value);
1189 type = TREE_TYPE (args[i].tree_value);
1190
1191 if (*ecf_flags & ECF_CONST)
1192 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1193 }
1194 else
1195 {
1196 /* We make a copy of the object and pass the address to the
1197 function being called. */
1198 rtx copy;
1199
1200 if (!COMPLETE_TYPE_P (type)
1201 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1202 || (flag_stack_check == GENERIC_STACK_CHECK
1203 && compare_tree_int (TYPE_SIZE_UNIT (type),
1204 STACK_CHECK_MAX_VAR_SIZE) > 0))
1205 {
1206 /* This is a variable-sized object. Make space on the stack
1207 for it. */
1208 rtx size_rtx = expr_size (args[i].tree_value);
1209
1210 if (*old_stack_level == 0)
1211 {
1212 emit_stack_save (SAVE_BLOCK, old_stack_level);
1213 *old_pending_adj = pending_stack_adjust;
1214 pending_stack_adjust = 0;
1215 }
1216
1217 /* We can pass TRUE as the 4th argument because we just
1218 saved the stack pointer and will restore it right after
1219 the call. */
1220 copy = allocate_dynamic_stack_space (size_rtx,
1221 TYPE_ALIGN (type),
1222 TYPE_ALIGN (type),
1223 true);
1224 copy = gen_rtx_MEM (BLKmode, copy);
1225 set_mem_attributes (copy, type, 1);
1226 }
1227 else
1228 copy = assign_temp (type, 0, 1, 0);
1229
1230 store_expr (args[i].tree_value, copy, 0, false);
1231
1232 /* Just change the const function to pure and then let
1233 the next test clear the pure based on
1234 callee_copies. */
1235 if (*ecf_flags & ECF_CONST)
1236 {
1237 *ecf_flags &= ~ECF_CONST;
1238 *ecf_flags |= ECF_PURE;
1239 }
1240
1241 if (!callee_copies && *ecf_flags & ECF_PURE)
1242 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1243
1244 args[i].tree_value
1245 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1246 type = TREE_TYPE (args[i].tree_value);
1247 *may_tailcall = false;
1248 }
1249 }
1250
1251 unsignedp = TYPE_UNSIGNED (type);
1252 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1253 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1254
1255 args[i].unsignedp = unsignedp;
1256 args[i].mode = mode;
1257
1258 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1259 argpos < n_named_args);
1260
1261 /* If this is a sibling call and the machine has register windows, the
1262 register window has to be unwinded before calling the routine, so
1263 arguments have to go into the incoming registers. */
1264 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1265 args[i].tail_call_reg
1266 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1267 argpos < n_named_args);
1268 else
1269 args[i].tail_call_reg = args[i].reg;
1270
1271 if (args[i].reg)
1272 args[i].partial
1273 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1274 argpos < n_named_args);
1275
1276 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1277
1278 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1279 it means that we are to pass this arg in the register(s) designated
1280 by the PARALLEL, but also to pass it in the stack. */
1281 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1282 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1283 args[i].pass_on_stack = 1;
1284
1285 /* If this is an addressable type, we must preallocate the stack
1286 since we must evaluate the object into its final location.
1287
1288 If this is to be passed in both registers and the stack, it is simpler
1289 to preallocate. */
1290 if (TREE_ADDRESSABLE (type)
1291 || (args[i].pass_on_stack && args[i].reg != 0))
1292 *must_preallocate = 1;
1293
1294 /* Compute the stack-size of this argument. */
1295 if (args[i].reg == 0 || args[i].partial != 0
1296 || reg_parm_stack_space > 0
1297 || args[i].pass_on_stack)
1298 locate_and_pad_parm (mode, type,
1299 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1300 1,
1301 #else
1302 args[i].reg != 0,
1303 #endif
1304 args[i].pass_on_stack ? 0 : args[i].partial,
1305 fndecl, args_size, &args[i].locate);
1306 #ifdef BLOCK_REG_PADDING
1307 else
1308 /* The argument is passed entirely in registers. See at which
1309 end it should be padded. */
1310 args[i].locate.where_pad =
1311 BLOCK_REG_PADDING (mode, type,
1312 int_size_in_bytes (type) <= UNITS_PER_WORD);
1313 #endif
1314
1315 /* Update ARGS_SIZE, the total stack space for args so far. */
1316
1317 args_size->constant += args[i].locate.size.constant;
1318 if (args[i].locate.size.var)
1319 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1320
1321 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1322 have been used, etc. */
1323
1324 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1325 type, argpos < n_named_args);
1326 }
1327 }
1328
1329 /* Update ARGS_SIZE to contain the total size for the argument block.
1330 Return the original constant component of the argument block's size.
1331
1332 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1333 for arguments passed in registers. */
1334
1335 static int
compute_argument_block_size(int reg_parm_stack_space,struct args_size * args_size,tree fndecl ATTRIBUTE_UNUSED,tree fntype ATTRIBUTE_UNUSED,int preferred_stack_boundary ATTRIBUTE_UNUSED)1336 compute_argument_block_size (int reg_parm_stack_space,
1337 struct args_size *args_size,
1338 tree fndecl ATTRIBUTE_UNUSED,
1339 tree fntype ATTRIBUTE_UNUSED,
1340 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1341 {
1342 int unadjusted_args_size = args_size->constant;
1343
1344 /* For accumulate outgoing args mode we don't need to align, since the frame
1345 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1346 backends from generating misaligned frame sizes. */
1347 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1348 preferred_stack_boundary = STACK_BOUNDARY;
1349
1350 /* Compute the actual size of the argument block required. The variable
1351 and constant sizes must be combined, the size may have to be rounded,
1352 and there may be a minimum required size. */
1353
1354 if (args_size->var)
1355 {
1356 args_size->var = ARGS_SIZE_TREE (*args_size);
1357 args_size->constant = 0;
1358
1359 preferred_stack_boundary /= BITS_PER_UNIT;
1360 if (preferred_stack_boundary > 1)
1361 {
1362 /* We don't handle this case yet. To handle it correctly we have
1363 to add the delta, round and subtract the delta.
1364 Currently no machine description requires this support. */
1365 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1366 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1367 }
1368
1369 if (reg_parm_stack_space > 0)
1370 {
1371 args_size->var
1372 = size_binop (MAX_EXPR, args_size->var,
1373 ssize_int (reg_parm_stack_space));
1374
1375 /* The area corresponding to register parameters is not to count in
1376 the size of the block we need. So make the adjustment. */
1377 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1378 args_size->var
1379 = size_binop (MINUS_EXPR, args_size->var,
1380 ssize_int (reg_parm_stack_space));
1381 }
1382 }
1383 else
1384 {
1385 preferred_stack_boundary /= BITS_PER_UNIT;
1386 if (preferred_stack_boundary < 1)
1387 preferred_stack_boundary = 1;
1388 args_size->constant = (((args_size->constant
1389 + stack_pointer_delta
1390 + preferred_stack_boundary - 1)
1391 / preferred_stack_boundary
1392 * preferred_stack_boundary)
1393 - stack_pointer_delta);
1394
1395 args_size->constant = MAX (args_size->constant,
1396 reg_parm_stack_space);
1397
1398 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1399 args_size->constant -= reg_parm_stack_space;
1400 }
1401 return unadjusted_args_size;
1402 }
1403
1404 /* Precompute parameters as needed for a function call.
1405
1406 FLAGS is mask of ECF_* constants.
1407
1408 NUM_ACTUALS is the number of arguments.
1409
1410 ARGS is an array containing information for each argument; this
1411 routine fills in the INITIAL_VALUE and VALUE fields for each
1412 precomputed argument. */
1413
1414 static void
precompute_arguments(int num_actuals,struct arg_data * args)1415 precompute_arguments (int num_actuals, struct arg_data *args)
1416 {
1417 int i;
1418
1419 /* If this is a libcall, then precompute all arguments so that we do not
1420 get extraneous instructions emitted as part of the libcall sequence. */
1421
1422 /* If we preallocated the stack space, and some arguments must be passed
1423 on the stack, then we must precompute any parameter which contains a
1424 function call which will store arguments on the stack.
1425 Otherwise, evaluating the parameter may clobber previous parameters
1426 which have already been stored into the stack. (we have code to avoid
1427 such case by saving the outgoing stack arguments, but it results in
1428 worse code) */
1429 if (!ACCUMULATE_OUTGOING_ARGS)
1430 return;
1431
1432 for (i = 0; i < num_actuals; i++)
1433 {
1434 tree type;
1435 enum machine_mode mode;
1436
1437 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1438 continue;
1439
1440 /* If this is an addressable type, we cannot pre-evaluate it. */
1441 type = TREE_TYPE (args[i].tree_value);
1442 gcc_assert (!TREE_ADDRESSABLE (type));
1443
1444 args[i].initial_value = args[i].value
1445 = expand_normal (args[i].tree_value);
1446
1447 mode = TYPE_MODE (type);
1448 if (mode != args[i].mode)
1449 {
1450 int unsignedp = args[i].unsignedp;
1451 args[i].value
1452 = convert_modes (args[i].mode, mode,
1453 args[i].value, args[i].unsignedp);
1454
1455 /* CSE will replace this only if it contains args[i].value
1456 pseudo, so convert it down to the declared mode using
1457 a SUBREG. */
1458 if (REG_P (args[i].value)
1459 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1460 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1461 {
1462 args[i].initial_value
1463 = gen_lowpart_SUBREG (mode, args[i].value);
1464 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1465 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1466 args[i].unsignedp);
1467 }
1468 }
1469 }
1470 }
1471
1472 /* Given the current state of MUST_PREALLOCATE and information about
1473 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1474 compute and return the final value for MUST_PREALLOCATE. */
1475
1476 static int
finalize_must_preallocate(int must_preallocate,int num_actuals,struct arg_data * args,struct args_size * args_size)1477 finalize_must_preallocate (int must_preallocate, int num_actuals,
1478 struct arg_data *args, struct args_size *args_size)
1479 {
1480 /* See if we have or want to preallocate stack space.
1481
1482 If we would have to push a partially-in-regs parm
1483 before other stack parms, preallocate stack space instead.
1484
1485 If the size of some parm is not a multiple of the required stack
1486 alignment, we must preallocate.
1487
1488 If the total size of arguments that would otherwise create a copy in
1489 a temporary (such as a CALL) is more than half the total argument list
1490 size, preallocation is faster.
1491
1492 Another reason to preallocate is if we have a machine (like the m88k)
1493 where stack alignment is required to be maintained between every
1494 pair of insns, not just when the call is made. However, we assume here
1495 that such machines either do not have push insns (and hence preallocation
1496 would occur anyway) or the problem is taken care of with
1497 PUSH_ROUNDING. */
1498
1499 if (! must_preallocate)
1500 {
1501 int partial_seen = 0;
1502 int copy_to_evaluate_size = 0;
1503 int i;
1504
1505 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1506 {
1507 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1508 partial_seen = 1;
1509 else if (partial_seen && args[i].reg == 0)
1510 must_preallocate = 1;
1511
1512 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1513 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1514 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1515 || TREE_CODE (args[i].tree_value) == COND_EXPR
1516 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1517 copy_to_evaluate_size
1518 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1519 }
1520
1521 if (copy_to_evaluate_size * 2 >= args_size->constant
1522 && args_size->constant > 0)
1523 must_preallocate = 1;
1524 }
1525 return must_preallocate;
1526 }
1527
1528 /* If we preallocated stack space, compute the address of each argument
1529 and store it into the ARGS array.
1530
1531 We need not ensure it is a valid memory address here; it will be
1532 validized when it is used.
1533
1534 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1535
1536 static void
compute_argument_addresses(struct arg_data * args,rtx argblock,int num_actuals)1537 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1538 {
1539 if (argblock)
1540 {
1541 rtx arg_reg = argblock;
1542 int i, arg_offset = 0;
1543
1544 if (GET_CODE (argblock) == PLUS)
1545 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1546
1547 for (i = 0; i < num_actuals; i++)
1548 {
1549 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1550 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1551 rtx addr;
1552 unsigned int align, boundary;
1553 unsigned int units_on_stack = 0;
1554 enum machine_mode partial_mode = VOIDmode;
1555
1556 /* Skip this parm if it will not be passed on the stack. */
1557 if (! args[i].pass_on_stack
1558 && args[i].reg != 0
1559 && args[i].partial == 0)
1560 continue;
1561
1562 if (CONST_INT_P (offset))
1563 addr = plus_constant (arg_reg, INTVAL (offset));
1564 else
1565 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1566
1567 addr = plus_constant (addr, arg_offset);
1568
1569 if (args[i].partial != 0)
1570 {
1571 /* Only part of the parameter is being passed on the stack.
1572 Generate a simple memory reference of the correct size. */
1573 units_on_stack = args[i].locate.size.constant;
1574 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1575 MODE_INT, 1);
1576 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1577 set_mem_size (args[i].stack, units_on_stack);
1578 }
1579 else
1580 {
1581 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1582 set_mem_attributes (args[i].stack,
1583 TREE_TYPE (args[i].tree_value), 1);
1584 }
1585 align = BITS_PER_UNIT;
1586 boundary = args[i].locate.boundary;
1587 if (args[i].locate.where_pad != downward)
1588 align = boundary;
1589 else if (CONST_INT_P (offset))
1590 {
1591 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1592 align = align & -align;
1593 }
1594 set_mem_align (args[i].stack, align);
1595
1596 if (CONST_INT_P (slot_offset))
1597 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1598 else
1599 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1600
1601 addr = plus_constant (addr, arg_offset);
1602
1603 if (args[i].partial != 0)
1604 {
1605 /* Only part of the parameter is being passed on the stack.
1606 Generate a simple memory reference of the correct size.
1607 */
1608 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1609 set_mem_size (args[i].stack_slot, units_on_stack);
1610 }
1611 else
1612 {
1613 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1614 set_mem_attributes (args[i].stack_slot,
1615 TREE_TYPE (args[i].tree_value), 1);
1616 }
1617 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1618
1619 /* Function incoming arguments may overlap with sibling call
1620 outgoing arguments and we cannot allow reordering of reads
1621 from function arguments with stores to outgoing arguments
1622 of sibling calls. */
1623 set_mem_alias_set (args[i].stack, 0);
1624 set_mem_alias_set (args[i].stack_slot, 0);
1625 }
1626 }
1627 }
1628
1629 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1630 in a call instruction.
1631
1632 FNDECL is the tree node for the target function. For an indirect call
1633 FNDECL will be NULL_TREE.
1634
1635 ADDR is the operand 0 of CALL_EXPR for this call. */
1636
1637 static rtx
rtx_for_function_call(tree fndecl,tree addr)1638 rtx_for_function_call (tree fndecl, tree addr)
1639 {
1640 rtx funexp;
1641
1642 /* Get the function to call, in the form of RTL. */
1643 if (fndecl)
1644 {
1645 /* If this is the first use of the function, see if we need to
1646 make an external definition for it. */
1647 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1648 {
1649 assemble_external (fndecl);
1650 TREE_USED (fndecl) = 1;
1651 }
1652
1653 /* Get a SYMBOL_REF rtx for the function address. */
1654 funexp = XEXP (DECL_RTL (fndecl), 0);
1655 }
1656 else
1657 /* Generate an rtx (probably a pseudo-register) for the address. */
1658 {
1659 push_temp_slots ();
1660 funexp = expand_normal (addr);
1661 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1662 }
1663 return funexp;
1664 }
1665
1666 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1667 static struct
1668 {
1669 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1670 or NULL_RTX if none has been scanned yet. */
1671 rtx scan_start;
1672 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1673 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1674 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1675 with fixed offset, or PC if this is with variable or unknown offset. */
1676 VEC(rtx, heap) *cache;
1677 } internal_arg_pointer_exp_state;
1678
1679 static rtx internal_arg_pointer_based_exp (rtx, bool);
1680
1681 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1682 the tail call sequence, starting with first insn that hasn't been
1683 scanned yet, and note for each pseudo on the LHS whether it is based
1684 on crtl->args.internal_arg_pointer or not, and what offset from that
1685 that pointer it has. */
1686
1687 static void
internal_arg_pointer_based_exp_scan(void)1688 internal_arg_pointer_based_exp_scan (void)
1689 {
1690 rtx insn, scan_start = internal_arg_pointer_exp_state.scan_start;
1691
1692 if (scan_start == NULL_RTX)
1693 insn = get_insns ();
1694 else
1695 insn = NEXT_INSN (scan_start);
1696
1697 while (insn)
1698 {
1699 rtx set = single_set (insn);
1700 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1701 {
1702 rtx val = NULL_RTX;
1703 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1704 /* Punt on pseudos set multiple times. */
1705 if (idx < VEC_length (rtx, internal_arg_pointer_exp_state.cache)
1706 && (VEC_index (rtx, internal_arg_pointer_exp_state.cache, idx)
1707 != NULL_RTX))
1708 val = pc_rtx;
1709 else
1710 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1711 if (val != NULL_RTX)
1712 {
1713 if (idx
1714 >= VEC_length (rtx, internal_arg_pointer_exp_state.cache))
1715 VEC_safe_grow_cleared (rtx, heap,
1716 internal_arg_pointer_exp_state.cache,
1717 idx + 1);
1718 VEC_replace (rtx, internal_arg_pointer_exp_state.cache,
1719 idx, val);
1720 }
1721 }
1722 if (NEXT_INSN (insn) == NULL_RTX)
1723 scan_start = insn;
1724 insn = NEXT_INSN (insn);
1725 }
1726
1727 internal_arg_pointer_exp_state.scan_start = scan_start;
1728 }
1729
1730 /* Helper function for internal_arg_pointer_based_exp, called through
1731 for_each_rtx. Return 1 if *LOC is a register based on
1732 crtl->args.internal_arg_pointer. Return -1 if *LOC is not based on it
1733 and the subexpressions need not be examined. Otherwise return 0. */
1734
1735 static int
internal_arg_pointer_based_exp_1(rtx * loc,void * data ATTRIBUTE_UNUSED)1736 internal_arg_pointer_based_exp_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
1737 {
1738 if (REG_P (*loc) && internal_arg_pointer_based_exp (*loc, false) != NULL_RTX)
1739 return 1;
1740 if (MEM_P (*loc))
1741 return -1;
1742 return 0;
1743 }
1744
1745 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1746 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1747 it with fixed offset, or PC if this is with variable or unknown offset.
1748 TOPLEVEL is true if the function is invoked at the topmost level. */
1749
1750 static rtx
internal_arg_pointer_based_exp(rtx rtl,bool toplevel)1751 internal_arg_pointer_based_exp (rtx rtl, bool toplevel)
1752 {
1753 if (CONSTANT_P (rtl))
1754 return NULL_RTX;
1755
1756 if (rtl == crtl->args.internal_arg_pointer)
1757 return const0_rtx;
1758
1759 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1760 return NULL_RTX;
1761
1762 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1763 {
1764 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1765 if (val == NULL_RTX || val == pc_rtx)
1766 return val;
1767 return plus_constant (val, INTVAL (XEXP (rtl, 1)));
1768 }
1769
1770 /* When called at the topmost level, scan pseudo assignments in between the
1771 last scanned instruction in the tail call sequence and the latest insn
1772 in that sequence. */
1773 if (toplevel)
1774 internal_arg_pointer_based_exp_scan ();
1775
1776 if (REG_P (rtl))
1777 {
1778 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1779 if (idx < VEC_length (rtx, internal_arg_pointer_exp_state.cache))
1780 return VEC_index (rtx, internal_arg_pointer_exp_state.cache, idx);
1781
1782 return NULL_RTX;
1783 }
1784
1785 if (for_each_rtx (&rtl, internal_arg_pointer_based_exp_1, NULL))
1786 return pc_rtx;
1787
1788 return NULL_RTX;
1789 }
1790
1791 /* Return true if and only if SIZE storage units (usually bytes)
1792 starting from address ADDR overlap with already clobbered argument
1793 area. This function is used to determine if we should give up a
1794 sibcall. */
1795
1796 static bool
mem_overlaps_already_clobbered_arg_p(rtx addr,unsigned HOST_WIDE_INT size)1797 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1798 {
1799 HOST_WIDE_INT i;
1800 rtx val;
1801
1802 if (sbitmap_empty_p (stored_args_map))
1803 return false;
1804 val = internal_arg_pointer_based_exp (addr, true);
1805 if (val == NULL_RTX)
1806 return false;
1807 else if (val == pc_rtx)
1808 return true;
1809 else
1810 i = INTVAL (val);
1811 #ifdef STACK_GROWS_DOWNWARD
1812 i -= crtl->args.pretend_args_size;
1813 #else
1814 i += crtl->args.pretend_args_size;
1815 #endif
1816
1817 #ifdef ARGS_GROW_DOWNWARD
1818 i = -i - size;
1819 #endif
1820 if (size > 0)
1821 {
1822 unsigned HOST_WIDE_INT k;
1823
1824 for (k = 0; k < size; k++)
1825 if (i + k < stored_args_map->n_bits
1826 && TEST_BIT (stored_args_map, i + k))
1827 return true;
1828 }
1829
1830 return false;
1831 }
1832
1833 /* Do the register loads required for any wholly-register parms or any
1834 parms which are passed both on the stack and in a register. Their
1835 expressions were already evaluated.
1836
1837 Mark all register-parms as living through the call, putting these USE
1838 insns in the CALL_INSN_FUNCTION_USAGE field.
1839
1840 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1841 checking, setting *SIBCALL_FAILURE if appropriate. */
1842
1843 static void
load_register_parameters(struct arg_data * args,int num_actuals,rtx * call_fusage,int flags,int is_sibcall,int * sibcall_failure)1844 load_register_parameters (struct arg_data *args, int num_actuals,
1845 rtx *call_fusage, int flags, int is_sibcall,
1846 int *sibcall_failure)
1847 {
1848 int i, j;
1849
1850 for (i = 0; i < num_actuals; i++)
1851 {
1852 rtx reg = ((flags & ECF_SIBCALL)
1853 ? args[i].tail_call_reg : args[i].reg);
1854 if (reg)
1855 {
1856 int partial = args[i].partial;
1857 int nregs;
1858 int size = 0;
1859 rtx before_arg = get_last_insn ();
1860 /* Set non-negative if we must move a word at a time, even if
1861 just one word (e.g, partial == 4 && mode == DFmode). Set
1862 to -1 if we just use a normal move insn. This value can be
1863 zero if the argument is a zero size structure. */
1864 nregs = -1;
1865 if (GET_CODE (reg) == PARALLEL)
1866 ;
1867 else if (partial)
1868 {
1869 gcc_assert (partial % UNITS_PER_WORD == 0);
1870 nregs = partial / UNITS_PER_WORD;
1871 }
1872 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1873 {
1874 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1875 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1876 }
1877 else
1878 size = GET_MODE_SIZE (args[i].mode);
1879
1880 /* Handle calls that pass values in multiple non-contiguous
1881 locations. The Irix 6 ABI has examples of this. */
1882
1883 if (GET_CODE (reg) == PARALLEL)
1884 emit_group_move (reg, args[i].parallel_value);
1885
1886 /* If simple case, just do move. If normal partial, store_one_arg
1887 has already loaded the register for us. In all other cases,
1888 load the register(s) from memory. */
1889
1890 else if (nregs == -1)
1891 {
1892 emit_move_insn (reg, args[i].value);
1893 #ifdef BLOCK_REG_PADDING
1894 /* Handle case where we have a value that needs shifting
1895 up to the msb. eg. a QImode value and we're padding
1896 upward on a BYTES_BIG_ENDIAN machine. */
1897 if (size < UNITS_PER_WORD
1898 && (args[i].locate.where_pad
1899 == (BYTES_BIG_ENDIAN ? upward : downward)))
1900 {
1901 rtx x;
1902 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1903
1904 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1905 report the whole reg as used. Strictly speaking, the
1906 call only uses SIZE bytes at the msb end, but it doesn't
1907 seem worth generating rtl to say that. */
1908 reg = gen_rtx_REG (word_mode, REGNO (reg));
1909 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
1910 if (x != reg)
1911 emit_move_insn (reg, x);
1912 }
1913 #endif
1914 }
1915
1916 /* If we have pre-computed the values to put in the registers in
1917 the case of non-aligned structures, copy them in now. */
1918
1919 else if (args[i].n_aligned_regs != 0)
1920 for (j = 0; j < args[i].n_aligned_regs; j++)
1921 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1922 args[i].aligned_regs[j]);
1923
1924 else if (partial == 0 || args[i].pass_on_stack)
1925 {
1926 rtx mem = validize_mem (args[i].value);
1927
1928 /* Check for overlap with already clobbered argument area,
1929 providing that this has non-zero size. */
1930 if (is_sibcall
1931 && (size == 0
1932 || mem_overlaps_already_clobbered_arg_p
1933 (XEXP (args[i].value, 0), size)))
1934 *sibcall_failure = 1;
1935
1936 /* Handle a BLKmode that needs shifting. */
1937 if (nregs == 1 && size < UNITS_PER_WORD
1938 #ifdef BLOCK_REG_PADDING
1939 && args[i].locate.where_pad == downward
1940 #else
1941 && BYTES_BIG_ENDIAN
1942 #endif
1943 )
1944 {
1945 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1946 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1947 rtx x = gen_reg_rtx (word_mode);
1948 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1949 enum tree_code dir = BYTES_BIG_ENDIAN ? RSHIFT_EXPR
1950 : LSHIFT_EXPR;
1951
1952 emit_move_insn (x, tem);
1953 x = expand_shift (dir, word_mode, x, shift, ri, 1);
1954 if (x != ri)
1955 emit_move_insn (ri, x);
1956 }
1957 else
1958 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1959 }
1960
1961 /* When a parameter is a block, and perhaps in other cases, it is
1962 possible that it did a load from an argument slot that was
1963 already clobbered. */
1964 if (is_sibcall
1965 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1966 *sibcall_failure = 1;
1967
1968 /* Handle calls that pass values in multiple non-contiguous
1969 locations. The Irix 6 ABI has examples of this. */
1970 if (GET_CODE (reg) == PARALLEL)
1971 use_group_regs (call_fusage, reg);
1972 else if (nregs == -1)
1973 use_reg_mode (call_fusage, reg,
1974 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
1975 else if (nregs > 0)
1976 use_regs (call_fusage, REGNO (reg), nregs);
1977 }
1978 }
1979 }
1980
1981 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1982 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1983 bytes, then we would need to push some additional bytes to pad the
1984 arguments. So, we compute an adjust to the stack pointer for an
1985 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1986 bytes. Then, when the arguments are pushed the stack will be perfectly
1987 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1988 be popped after the call. Returns the adjustment. */
1989
1990 static int
combine_pending_stack_adjustment_and_call(int unadjusted_args_size,struct args_size * args_size,unsigned int preferred_unit_stack_boundary)1991 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1992 struct args_size *args_size,
1993 unsigned int preferred_unit_stack_boundary)
1994 {
1995 /* The number of bytes to pop so that the stack will be
1996 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1997 HOST_WIDE_INT adjustment;
1998 /* The alignment of the stack after the arguments are pushed, if we
1999 just pushed the arguments without adjust the stack here. */
2000 unsigned HOST_WIDE_INT unadjusted_alignment;
2001
2002 unadjusted_alignment
2003 = ((stack_pointer_delta + unadjusted_args_size)
2004 % preferred_unit_stack_boundary);
2005
2006 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2007 as possible -- leaving just enough left to cancel out the
2008 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2009 PENDING_STACK_ADJUST is non-negative, and congruent to
2010 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2011
2012 /* Begin by trying to pop all the bytes. */
2013 unadjusted_alignment
2014 = (unadjusted_alignment
2015 - (pending_stack_adjust % preferred_unit_stack_boundary));
2016 adjustment = pending_stack_adjust;
2017 /* Push enough additional bytes that the stack will be aligned
2018 after the arguments are pushed. */
2019 if (preferred_unit_stack_boundary > 1)
2020 {
2021 if (unadjusted_alignment > 0)
2022 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2023 else
2024 adjustment += unadjusted_alignment;
2025 }
2026
2027 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2028 bytes after the call. The right number is the entire
2029 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2030 by the arguments in the first place. */
2031 args_size->constant
2032 = pending_stack_adjust - adjustment + unadjusted_args_size;
2033
2034 return adjustment;
2035 }
2036
2037 /* Scan X expression if it does not dereference any argument slots
2038 we already clobbered by tail call arguments (as noted in stored_args_map
2039 bitmap).
2040 Return nonzero if X expression dereferences such argument slots,
2041 zero otherwise. */
2042
2043 static int
check_sibcall_argument_overlap_1(rtx x)2044 check_sibcall_argument_overlap_1 (rtx x)
2045 {
2046 RTX_CODE code;
2047 int i, j;
2048 const char *fmt;
2049
2050 if (x == NULL_RTX)
2051 return 0;
2052
2053 code = GET_CODE (x);
2054
2055 /* We need not check the operands of the CALL expression itself. */
2056 if (code == CALL)
2057 return 0;
2058
2059 if (code == MEM)
2060 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2061 GET_MODE_SIZE (GET_MODE (x)));
2062
2063 /* Scan all subexpressions. */
2064 fmt = GET_RTX_FORMAT (code);
2065 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2066 {
2067 if (*fmt == 'e')
2068 {
2069 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2070 return 1;
2071 }
2072 else if (*fmt == 'E')
2073 {
2074 for (j = 0; j < XVECLEN (x, i); j++)
2075 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2076 return 1;
2077 }
2078 }
2079 return 0;
2080 }
2081
2082 /* Scan sequence after INSN if it does not dereference any argument slots
2083 we already clobbered by tail call arguments (as noted in stored_args_map
2084 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2085 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2086 should be 0). Return nonzero if sequence after INSN dereferences such argument
2087 slots, zero otherwise. */
2088
2089 static int
check_sibcall_argument_overlap(rtx insn,struct arg_data * arg,int mark_stored_args_map)2090 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
2091 {
2092 int low, high;
2093
2094 if (insn == NULL_RTX)
2095 insn = get_insns ();
2096 else
2097 insn = NEXT_INSN (insn);
2098
2099 for (; insn; insn = NEXT_INSN (insn))
2100 if (INSN_P (insn)
2101 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2102 break;
2103
2104 if (mark_stored_args_map)
2105 {
2106 #ifdef ARGS_GROW_DOWNWARD
2107 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2108 #else
2109 low = arg->locate.slot_offset.constant;
2110 #endif
2111
2112 for (high = low + arg->locate.size.constant; low < high; low++)
2113 SET_BIT (stored_args_map, low);
2114 }
2115 return insn != NULL_RTX;
2116 }
2117
2118 /* Given that a function returns a value of mode MODE at the most
2119 significant end of hard register VALUE, shift VALUE left or right
2120 as specified by LEFT_P. Return true if some action was needed. */
2121
2122 bool
shift_return_value(enum machine_mode mode,bool left_p,rtx value)2123 shift_return_value (enum machine_mode mode, bool left_p, rtx value)
2124 {
2125 HOST_WIDE_INT shift;
2126
2127 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2128 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2129 if (shift == 0)
2130 return false;
2131
2132 /* Use ashr rather than lshr for right shifts. This is for the benefit
2133 of the MIPS port, which requires SImode values to be sign-extended
2134 when stored in 64-bit registers. */
2135 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2136 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2137 gcc_unreachable ();
2138 return true;
2139 }
2140
2141 /* If X is a likely-spilled register value, copy it to a pseudo
2142 register and return that register. Return X otherwise. */
2143
2144 static rtx
avoid_likely_spilled_reg(rtx x)2145 avoid_likely_spilled_reg (rtx x)
2146 {
2147 rtx new_rtx;
2148
2149 if (REG_P (x)
2150 && HARD_REGISTER_P (x)
2151 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2152 {
2153 /* Make sure that we generate a REG rather than a CONCAT.
2154 Moves into CONCATs can need nontrivial instructions,
2155 and the whole point of this function is to avoid
2156 using the hard register directly in such a situation. */
2157 generating_concat_p = 0;
2158 new_rtx = gen_reg_rtx (GET_MODE (x));
2159 generating_concat_p = 1;
2160 emit_move_insn (new_rtx, x);
2161 return new_rtx;
2162 }
2163 return x;
2164 }
2165
2166 /* Generate all the code for a CALL_EXPR exp
2167 and return an rtx for its value.
2168 Store the value in TARGET (specified as an rtx) if convenient.
2169 If the value is stored in TARGET then TARGET is returned.
2170 If IGNORE is nonzero, then we ignore the value of the function call. */
2171
2172 rtx
expand_call(tree exp,rtx target,int ignore)2173 expand_call (tree exp, rtx target, int ignore)
2174 {
2175 /* Nonzero if we are currently expanding a call. */
2176 static int currently_expanding_call = 0;
2177
2178 /* RTX for the function to be called. */
2179 rtx funexp;
2180 /* Sequence of insns to perform a normal "call". */
2181 rtx normal_call_insns = NULL_RTX;
2182 /* Sequence of insns to perform a tail "call". */
2183 rtx tail_call_insns = NULL_RTX;
2184 /* Data type of the function. */
2185 tree funtype;
2186 tree type_arg_types;
2187 tree rettype;
2188 /* Declaration of the function being called,
2189 or 0 if the function is computed (not known by name). */
2190 tree fndecl = 0;
2191 /* The type of the function being called. */
2192 tree fntype;
2193 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2194 int pass;
2195
2196 /* Register in which non-BLKmode value will be returned,
2197 or 0 if no value or if value is BLKmode. */
2198 rtx valreg;
2199 /* Address where we should return a BLKmode value;
2200 0 if value not BLKmode. */
2201 rtx structure_value_addr = 0;
2202 /* Nonzero if that address is being passed by treating it as
2203 an extra, implicit first parameter. Otherwise,
2204 it is passed by being copied directly into struct_value_rtx. */
2205 int structure_value_addr_parm = 0;
2206 /* Holds the value of implicit argument for the struct value. */
2207 tree structure_value_addr_value = NULL_TREE;
2208 /* Size of aggregate value wanted, or zero if none wanted
2209 or if we are using the non-reentrant PCC calling convention
2210 or expecting the value in registers. */
2211 HOST_WIDE_INT struct_value_size = 0;
2212 /* Nonzero if called function returns an aggregate in memory PCC style,
2213 by returning the address of where to find it. */
2214 int pcc_struct_value = 0;
2215 rtx struct_value = 0;
2216
2217 /* Number of actual parameters in this call, including struct value addr. */
2218 int num_actuals;
2219 /* Number of named args. Args after this are anonymous ones
2220 and they must all go on the stack. */
2221 int n_named_args;
2222 /* Number of complex actual arguments that need to be split. */
2223 int num_complex_actuals = 0;
2224
2225 /* Vector of information about each argument.
2226 Arguments are numbered in the order they will be pushed,
2227 not the order they are written. */
2228 struct arg_data *args;
2229
2230 /* Total size in bytes of all the stack-parms scanned so far. */
2231 struct args_size args_size;
2232 struct args_size adjusted_args_size;
2233 /* Size of arguments before any adjustments (such as rounding). */
2234 int unadjusted_args_size;
2235 /* Data on reg parms scanned so far. */
2236 CUMULATIVE_ARGS args_so_far_v;
2237 cumulative_args_t args_so_far;
2238 /* Nonzero if a reg parm has been scanned. */
2239 int reg_parm_seen;
2240 /* Nonzero if this is an indirect function call. */
2241
2242 /* Nonzero if we must avoid push-insns in the args for this call.
2243 If stack space is allocated for register parameters, but not by the
2244 caller, then it is preallocated in the fixed part of the stack frame.
2245 So the entire argument block must then be preallocated (i.e., we
2246 ignore PUSH_ROUNDING in that case). */
2247
2248 int must_preallocate = !PUSH_ARGS;
2249
2250 /* Size of the stack reserved for parameter registers. */
2251 int reg_parm_stack_space = 0;
2252
2253 /* Address of space preallocated for stack parms
2254 (on machines that lack push insns), or 0 if space not preallocated. */
2255 rtx argblock = 0;
2256
2257 /* Mask of ECF_ flags. */
2258 int flags = 0;
2259 #ifdef REG_PARM_STACK_SPACE
2260 /* Define the boundary of the register parm stack space that needs to be
2261 saved, if any. */
2262 int low_to_save, high_to_save;
2263 rtx save_area = 0; /* Place that it is saved */
2264 #endif
2265
2266 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2267 char *initial_stack_usage_map = stack_usage_map;
2268 char *stack_usage_map_buf = NULL;
2269
2270 int old_stack_allocated;
2271
2272 /* State variables to track stack modifications. */
2273 rtx old_stack_level = 0;
2274 int old_stack_arg_under_construction = 0;
2275 int old_pending_adj = 0;
2276 int old_inhibit_defer_pop = inhibit_defer_pop;
2277
2278 /* Some stack pointer alterations we make are performed via
2279 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2280 which we then also need to save/restore along the way. */
2281 int old_stack_pointer_delta = 0;
2282
2283 rtx call_fusage;
2284 tree addr = CALL_EXPR_FN (exp);
2285 int i;
2286 /* The alignment of the stack, in bits. */
2287 unsigned HOST_WIDE_INT preferred_stack_boundary;
2288 /* The alignment of the stack, in bytes. */
2289 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2290 /* The static chain value to use for this call. */
2291 rtx static_chain_value;
2292 /* See if this is "nothrow" function call. */
2293 if (TREE_NOTHROW (exp))
2294 flags |= ECF_NOTHROW;
2295
2296 /* See if we can find a DECL-node for the actual function, and get the
2297 function attributes (flags) from the function decl or type node. */
2298 fndecl = get_callee_fndecl (exp);
2299 if (fndecl)
2300 {
2301 fntype = TREE_TYPE (fndecl);
2302 flags |= flags_from_decl_or_type (fndecl);
2303 }
2304 else
2305 {
2306 fntype = TREE_TYPE (TREE_TYPE (addr));
2307 flags |= flags_from_decl_or_type (fntype);
2308 }
2309 rettype = TREE_TYPE (exp);
2310
2311 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2312
2313 /* Warn if this value is an aggregate type,
2314 regardless of which calling convention we are using for it. */
2315 if (AGGREGATE_TYPE_P (rettype))
2316 warning (OPT_Waggregate_return, "function call has aggregate value");
2317
2318 /* If the result of a non looping pure or const function call is
2319 ignored (or void), and none of its arguments are volatile, we can
2320 avoid expanding the call and just evaluate the arguments for
2321 side-effects. */
2322 if ((flags & (ECF_CONST | ECF_PURE))
2323 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2324 && (ignore || target == const0_rtx
2325 || TYPE_MODE (rettype) == VOIDmode))
2326 {
2327 bool volatilep = false;
2328 tree arg;
2329 call_expr_arg_iterator iter;
2330
2331 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2332 if (TREE_THIS_VOLATILE (arg))
2333 {
2334 volatilep = true;
2335 break;
2336 }
2337
2338 if (! volatilep)
2339 {
2340 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2341 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2342 return const0_rtx;
2343 }
2344 }
2345
2346 #ifdef REG_PARM_STACK_SPACE
2347 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2348 #endif
2349
2350 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2351 && reg_parm_stack_space > 0 && PUSH_ARGS)
2352 must_preallocate = 1;
2353
2354 /* Set up a place to return a structure. */
2355
2356 /* Cater to broken compilers. */
2357 if (aggregate_value_p (exp, fntype))
2358 {
2359 /* This call returns a big structure. */
2360 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2361
2362 #ifdef PCC_STATIC_STRUCT_RETURN
2363 {
2364 pcc_struct_value = 1;
2365 }
2366 #else /* not PCC_STATIC_STRUCT_RETURN */
2367 {
2368 struct_value_size = int_size_in_bytes (rettype);
2369
2370 if (target && MEM_P (target) && CALL_EXPR_RETURN_SLOT_OPT (exp))
2371 structure_value_addr = XEXP (target, 0);
2372 else
2373 {
2374 /* For variable-sized objects, we must be called with a target
2375 specified. If we were to allocate space on the stack here,
2376 we would have no way of knowing when to free it. */
2377 rtx d = assign_temp (rettype, 0, 1, 1);
2378
2379 mark_temp_addr_taken (d);
2380 structure_value_addr = XEXP (d, 0);
2381 target = 0;
2382 }
2383 }
2384 #endif /* not PCC_STATIC_STRUCT_RETURN */
2385 }
2386
2387 /* Figure out the amount to which the stack should be aligned. */
2388 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2389 if (fndecl)
2390 {
2391 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2392 /* Without automatic stack alignment, we can't increase preferred
2393 stack boundary. With automatic stack alignment, it is
2394 unnecessary since unless we can guarantee that all callers will
2395 align the outgoing stack properly, callee has to align its
2396 stack anyway. */
2397 if (i
2398 && i->preferred_incoming_stack_boundary
2399 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2400 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2401 }
2402
2403 /* Operand 0 is a pointer-to-function; get the type of the function. */
2404 funtype = TREE_TYPE (addr);
2405 gcc_assert (POINTER_TYPE_P (funtype));
2406 funtype = TREE_TYPE (funtype);
2407
2408 /* Count whether there are actual complex arguments that need to be split
2409 into their real and imaginary parts. Munge the type_arg_types
2410 appropriately here as well. */
2411 if (targetm.calls.split_complex_arg)
2412 {
2413 call_expr_arg_iterator iter;
2414 tree arg;
2415 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2416 {
2417 tree type = TREE_TYPE (arg);
2418 if (type && TREE_CODE (type) == COMPLEX_TYPE
2419 && targetm.calls.split_complex_arg (type))
2420 num_complex_actuals++;
2421 }
2422 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2423 }
2424 else
2425 type_arg_types = TYPE_ARG_TYPES (funtype);
2426
2427 if (flags & ECF_MAY_BE_ALLOCA)
2428 cfun->calls_alloca = 1;
2429
2430 /* If struct_value_rtx is 0, it means pass the address
2431 as if it were an extra parameter. Put the argument expression
2432 in structure_value_addr_value. */
2433 if (structure_value_addr && struct_value == 0)
2434 {
2435 /* If structure_value_addr is a REG other than
2436 virtual_outgoing_args_rtx, we can use always use it. If it
2437 is not a REG, we must always copy it into a register.
2438 If it is virtual_outgoing_args_rtx, we must copy it to another
2439 register in some cases. */
2440 rtx temp = (!REG_P (structure_value_addr)
2441 || (ACCUMULATE_OUTGOING_ARGS
2442 && stack_arg_under_construction
2443 && structure_value_addr == virtual_outgoing_args_rtx)
2444 ? copy_addr_to_reg (convert_memory_address
2445 (Pmode, structure_value_addr))
2446 : structure_value_addr);
2447
2448 structure_value_addr_value =
2449 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2450 structure_value_addr_parm = 1;
2451 }
2452
2453 /* Count the arguments and set NUM_ACTUALS. */
2454 num_actuals =
2455 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2456
2457 /* Compute number of named args.
2458 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2459
2460 if (type_arg_types != 0)
2461 n_named_args
2462 = (list_length (type_arg_types)
2463 /* Count the struct value address, if it is passed as a parm. */
2464 + structure_value_addr_parm);
2465 else
2466 /* If we know nothing, treat all args as named. */
2467 n_named_args = num_actuals;
2468
2469 /* Start updating where the next arg would go.
2470
2471 On some machines (such as the PA) indirect calls have a different
2472 calling convention than normal calls. The fourth argument in
2473 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2474 or not. */
2475 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2476 args_so_far = pack_cumulative_args (&args_so_far_v);
2477
2478 /* Now possibly adjust the number of named args.
2479 Normally, don't include the last named arg if anonymous args follow.
2480 We do include the last named arg if
2481 targetm.calls.strict_argument_naming() returns nonzero.
2482 (If no anonymous args follow, the result of list_length is actually
2483 one too large. This is harmless.)
2484
2485 If targetm.calls.pretend_outgoing_varargs_named() returns
2486 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2487 this machine will be able to place unnamed args that were passed
2488 in registers into the stack. So treat all args as named. This
2489 allows the insns emitting for a specific argument list to be
2490 independent of the function declaration.
2491
2492 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2493 we do not have any reliable way to pass unnamed args in
2494 registers, so we must force them into memory. */
2495
2496 if (type_arg_types != 0
2497 && targetm.calls.strict_argument_naming (args_so_far))
2498 ;
2499 else if (type_arg_types != 0
2500 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2501 /* Don't include the last named arg. */
2502 --n_named_args;
2503 else
2504 /* Treat all args as named. */
2505 n_named_args = num_actuals;
2506
2507 /* Make a vector to hold all the information about each arg. */
2508 args = XALLOCAVEC (struct arg_data, num_actuals);
2509 memset (args, 0, num_actuals * sizeof (struct arg_data));
2510
2511 /* Build up entries in the ARGS array, compute the size of the
2512 arguments into ARGS_SIZE, etc. */
2513 initialize_argument_information (num_actuals, args, &args_size,
2514 n_named_args, exp,
2515 structure_value_addr_value, fndecl, fntype,
2516 args_so_far, reg_parm_stack_space,
2517 &old_stack_level, &old_pending_adj,
2518 &must_preallocate, &flags,
2519 &try_tail_call, CALL_FROM_THUNK_P (exp));
2520
2521 if (args_size.var)
2522 must_preallocate = 1;
2523
2524 /* Now make final decision about preallocating stack space. */
2525 must_preallocate = finalize_must_preallocate (must_preallocate,
2526 num_actuals, args,
2527 &args_size);
2528
2529 /* If the structure value address will reference the stack pointer, we
2530 must stabilize it. We don't need to do this if we know that we are
2531 not going to adjust the stack pointer in processing this call. */
2532
2533 if (structure_value_addr
2534 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2535 || reg_mentioned_p (virtual_outgoing_args_rtx,
2536 structure_value_addr))
2537 && (args_size.var
2538 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2539 structure_value_addr = copy_to_reg (structure_value_addr);
2540
2541 /* Tail calls can make things harder to debug, and we've traditionally
2542 pushed these optimizations into -O2. Don't try if we're already
2543 expanding a call, as that means we're an argument. Don't try if
2544 there's cleanups, as we know there's code to follow the call. */
2545
2546 if (currently_expanding_call++ != 0
2547 || !flag_optimize_sibling_calls
2548 || args_size.var
2549 || dbg_cnt (tail_call) == false)
2550 try_tail_call = 0;
2551
2552 /* Rest of purposes for tail call optimizations to fail. */
2553 if (
2554 #ifdef HAVE_sibcall_epilogue
2555 !HAVE_sibcall_epilogue
2556 #else
2557 1
2558 #endif
2559 || !try_tail_call
2560 /* Doing sibling call optimization needs some work, since
2561 structure_value_addr can be allocated on the stack.
2562 It does not seem worth the effort since few optimizable
2563 sibling calls will return a structure. */
2564 || structure_value_addr != NULL_RTX
2565 #ifdef REG_PARM_STACK_SPACE
2566 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2567 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2568 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2569 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (fndecl))
2570 #endif
2571 /* Check whether the target is able to optimize the call
2572 into a sibcall. */
2573 || !targetm.function_ok_for_sibcall (fndecl, exp)
2574 /* Functions that do not return exactly once may not be sibcall
2575 optimized. */
2576 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2577 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2578 /* If the called function is nested in the current one, it might access
2579 some of the caller's arguments, but could clobber them beforehand if
2580 the argument areas are shared. */
2581 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2582 /* If this function requires more stack slots than the current
2583 function, we cannot change it into a sibling call.
2584 crtl->args.pretend_args_size is not part of the
2585 stack allocated by our caller. */
2586 || args_size.constant > (crtl->args.size
2587 - crtl->args.pretend_args_size)
2588 /* If the callee pops its own arguments, then it must pop exactly
2589 the same number of arguments as the current function. */
2590 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2591 != targetm.calls.return_pops_args (current_function_decl,
2592 TREE_TYPE (current_function_decl),
2593 crtl->args.size))
2594 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2595 try_tail_call = 0;
2596
2597 /* Check if caller and callee disagree in promotion of function
2598 return value. */
2599 if (try_tail_call)
2600 {
2601 enum machine_mode caller_mode, caller_promoted_mode;
2602 enum machine_mode callee_mode, callee_promoted_mode;
2603 int caller_unsignedp, callee_unsignedp;
2604 tree caller_res = DECL_RESULT (current_function_decl);
2605
2606 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2607 caller_mode = DECL_MODE (caller_res);
2608 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2609 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2610 caller_promoted_mode
2611 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2612 &caller_unsignedp,
2613 TREE_TYPE (current_function_decl), 1);
2614 callee_promoted_mode
2615 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2616 &callee_unsignedp,
2617 funtype, 1);
2618 if (caller_mode != VOIDmode
2619 && (caller_promoted_mode != callee_promoted_mode
2620 || ((caller_mode != caller_promoted_mode
2621 || callee_mode != callee_promoted_mode)
2622 && (caller_unsignedp != callee_unsignedp
2623 || GET_MODE_BITSIZE (caller_mode)
2624 < GET_MODE_BITSIZE (callee_mode)))))
2625 try_tail_call = 0;
2626 }
2627
2628 /* Ensure current function's preferred stack boundary is at least
2629 what we need. Stack alignment may also increase preferred stack
2630 boundary. */
2631 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2632 crtl->preferred_stack_boundary = preferred_stack_boundary;
2633 else
2634 preferred_stack_boundary = crtl->preferred_stack_boundary;
2635
2636 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2637
2638 /* We want to make two insn chains; one for a sibling call, the other
2639 for a normal call. We will select one of the two chains after
2640 initial RTL generation is complete. */
2641 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2642 {
2643 int sibcall_failure = 0;
2644 /* We want to emit any pending stack adjustments before the tail
2645 recursion "call". That way we know any adjustment after the tail
2646 recursion call can be ignored if we indeed use the tail
2647 call expansion. */
2648 int save_pending_stack_adjust = 0;
2649 int save_stack_pointer_delta = 0;
2650 rtx insns;
2651 rtx before_call, next_arg_reg, after_args;
2652
2653 if (pass == 0)
2654 {
2655 /* State variables we need to save and restore between
2656 iterations. */
2657 save_pending_stack_adjust = pending_stack_adjust;
2658 save_stack_pointer_delta = stack_pointer_delta;
2659 }
2660 if (pass)
2661 flags &= ~ECF_SIBCALL;
2662 else
2663 flags |= ECF_SIBCALL;
2664
2665 /* Other state variables that we must reinitialize each time
2666 through the loop (that are not initialized by the loop itself). */
2667 argblock = 0;
2668 call_fusage = 0;
2669
2670 /* Start a new sequence for the normal call case.
2671
2672 From this point on, if the sibling call fails, we want to set
2673 sibcall_failure instead of continuing the loop. */
2674 start_sequence ();
2675
2676 /* Don't let pending stack adjusts add up to too much.
2677 Also, do all pending adjustments now if there is any chance
2678 this might be a call to alloca or if we are expanding a sibling
2679 call sequence.
2680 Also do the adjustments before a throwing call, otherwise
2681 exception handling can fail; PR 19225. */
2682 if (pending_stack_adjust >= 32
2683 || (pending_stack_adjust > 0
2684 && (flags & ECF_MAY_BE_ALLOCA))
2685 || (pending_stack_adjust > 0
2686 && flag_exceptions && !(flags & ECF_NOTHROW))
2687 || pass == 0)
2688 do_pending_stack_adjust ();
2689
2690 /* Precompute any arguments as needed. */
2691 if (pass)
2692 precompute_arguments (num_actuals, args);
2693
2694 /* Now we are about to start emitting insns that can be deleted
2695 if a libcall is deleted. */
2696 if (pass && (flags & ECF_MALLOC))
2697 start_sequence ();
2698
2699 if (pass == 0 && crtl->stack_protect_guard)
2700 stack_protect_epilogue ();
2701
2702 adjusted_args_size = args_size;
2703 /* Compute the actual size of the argument block required. The variable
2704 and constant sizes must be combined, the size may have to be rounded,
2705 and there may be a minimum required size. When generating a sibcall
2706 pattern, do not round up, since we'll be re-using whatever space our
2707 caller provided. */
2708 unadjusted_args_size
2709 = compute_argument_block_size (reg_parm_stack_space,
2710 &adjusted_args_size,
2711 fndecl, fntype,
2712 (pass == 0 ? 0
2713 : preferred_stack_boundary));
2714
2715 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2716
2717 /* The argument block when performing a sibling call is the
2718 incoming argument block. */
2719 if (pass == 0)
2720 {
2721 argblock = crtl->args.internal_arg_pointer;
2722 argblock
2723 #ifdef STACK_GROWS_DOWNWARD
2724 = plus_constant (argblock, crtl->args.pretend_args_size);
2725 #else
2726 = plus_constant (argblock, -crtl->args.pretend_args_size);
2727 #endif
2728 stored_args_map = sbitmap_alloc (args_size.constant);
2729 sbitmap_zero (stored_args_map);
2730 }
2731
2732 /* If we have no actual push instructions, or shouldn't use them,
2733 make space for all args right now. */
2734 else if (adjusted_args_size.var != 0)
2735 {
2736 if (old_stack_level == 0)
2737 {
2738 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2739 old_stack_pointer_delta = stack_pointer_delta;
2740 old_pending_adj = pending_stack_adjust;
2741 pending_stack_adjust = 0;
2742 /* stack_arg_under_construction says whether a stack arg is
2743 being constructed at the old stack level. Pushing the stack
2744 gets a clean outgoing argument block. */
2745 old_stack_arg_under_construction = stack_arg_under_construction;
2746 stack_arg_under_construction = 0;
2747 }
2748 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2749 if (flag_stack_usage_info)
2750 current_function_has_unbounded_dynamic_stack_size = 1;
2751 }
2752 else
2753 {
2754 /* Note that we must go through the motions of allocating an argument
2755 block even if the size is zero because we may be storing args
2756 in the area reserved for register arguments, which may be part of
2757 the stack frame. */
2758
2759 int needed = adjusted_args_size.constant;
2760
2761 /* Store the maximum argument space used. It will be pushed by
2762 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2763 checking). */
2764
2765 if (needed > crtl->outgoing_args_size)
2766 crtl->outgoing_args_size = needed;
2767
2768 if (must_preallocate)
2769 {
2770 if (ACCUMULATE_OUTGOING_ARGS)
2771 {
2772 /* Since the stack pointer will never be pushed, it is
2773 possible for the evaluation of a parm to clobber
2774 something we have already written to the stack.
2775 Since most function calls on RISC machines do not use
2776 the stack, this is uncommon, but must work correctly.
2777
2778 Therefore, we save any area of the stack that was already
2779 written and that we are using. Here we set up to do this
2780 by making a new stack usage map from the old one. The
2781 actual save will be done by store_one_arg.
2782
2783 Another approach might be to try to reorder the argument
2784 evaluations to avoid this conflicting stack usage. */
2785
2786 /* Since we will be writing into the entire argument area,
2787 the map must be allocated for its entire size, not just
2788 the part that is the responsibility of the caller. */
2789 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2790 needed += reg_parm_stack_space;
2791
2792 #ifdef ARGS_GROW_DOWNWARD
2793 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2794 needed + 1);
2795 #else
2796 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2797 needed);
2798 #endif
2799 free (stack_usage_map_buf);
2800 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2801 stack_usage_map = stack_usage_map_buf;
2802
2803 if (initial_highest_arg_in_use)
2804 memcpy (stack_usage_map, initial_stack_usage_map,
2805 initial_highest_arg_in_use);
2806
2807 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2808 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2809 (highest_outgoing_arg_in_use
2810 - initial_highest_arg_in_use));
2811 needed = 0;
2812
2813 /* The address of the outgoing argument list must not be
2814 copied to a register here, because argblock would be left
2815 pointing to the wrong place after the call to
2816 allocate_dynamic_stack_space below. */
2817
2818 argblock = virtual_outgoing_args_rtx;
2819 }
2820 else
2821 {
2822 if (inhibit_defer_pop == 0)
2823 {
2824 /* Try to reuse some or all of the pending_stack_adjust
2825 to get this space. */
2826 needed
2827 = (combine_pending_stack_adjustment_and_call
2828 (unadjusted_args_size,
2829 &adjusted_args_size,
2830 preferred_unit_stack_boundary));
2831
2832 /* combine_pending_stack_adjustment_and_call computes
2833 an adjustment before the arguments are allocated.
2834 Account for them and see whether or not the stack
2835 needs to go up or down. */
2836 needed = unadjusted_args_size - needed;
2837
2838 if (needed < 0)
2839 {
2840 /* We're releasing stack space. */
2841 /* ??? We can avoid any adjustment at all if we're
2842 already aligned. FIXME. */
2843 pending_stack_adjust = -needed;
2844 do_pending_stack_adjust ();
2845 needed = 0;
2846 }
2847 else
2848 /* We need to allocate space. We'll do that in
2849 push_block below. */
2850 pending_stack_adjust = 0;
2851 }
2852
2853 /* Special case this because overhead of `push_block' in
2854 this case is non-trivial. */
2855 if (needed == 0)
2856 argblock = virtual_outgoing_args_rtx;
2857 else
2858 {
2859 argblock = push_block (GEN_INT (needed), 0, 0);
2860 #ifdef ARGS_GROW_DOWNWARD
2861 argblock = plus_constant (argblock, needed);
2862 #endif
2863 }
2864
2865 /* We only really need to call `copy_to_reg' in the case
2866 where push insns are going to be used to pass ARGBLOCK
2867 to a function call in ARGS. In that case, the stack
2868 pointer changes value from the allocation point to the
2869 call point, and hence the value of
2870 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2871 as well always do it. */
2872 argblock = copy_to_reg (argblock);
2873 }
2874 }
2875 }
2876
2877 if (ACCUMULATE_OUTGOING_ARGS)
2878 {
2879 /* The save/restore code in store_one_arg handles all
2880 cases except one: a constructor call (including a C
2881 function returning a BLKmode struct) to initialize
2882 an argument. */
2883 if (stack_arg_under_construction)
2884 {
2885 rtx push_size
2886 = GEN_INT (adjusted_args_size.constant
2887 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
2888 : TREE_TYPE (fndecl))) ? 0
2889 : reg_parm_stack_space));
2890 if (old_stack_level == 0)
2891 {
2892 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2893 old_stack_pointer_delta = stack_pointer_delta;
2894 old_pending_adj = pending_stack_adjust;
2895 pending_stack_adjust = 0;
2896 /* stack_arg_under_construction says whether a stack
2897 arg is being constructed at the old stack level.
2898 Pushing the stack gets a clean outgoing argument
2899 block. */
2900 old_stack_arg_under_construction
2901 = stack_arg_under_construction;
2902 stack_arg_under_construction = 0;
2903 /* Make a new map for the new argument list. */
2904 free (stack_usage_map_buf);
2905 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
2906 stack_usage_map = stack_usage_map_buf;
2907 highest_outgoing_arg_in_use = 0;
2908 }
2909 /* We can pass TRUE as the 4th argument because we just
2910 saved the stack pointer and will restore it right after
2911 the call. */
2912 allocate_dynamic_stack_space (push_size, 0,
2913 BIGGEST_ALIGNMENT, true);
2914 }
2915
2916 /* If argument evaluation might modify the stack pointer,
2917 copy the address of the argument list to a register. */
2918 for (i = 0; i < num_actuals; i++)
2919 if (args[i].pass_on_stack)
2920 {
2921 argblock = copy_addr_to_reg (argblock);
2922 break;
2923 }
2924 }
2925
2926 compute_argument_addresses (args, argblock, num_actuals);
2927
2928 /* If we push args individually in reverse order, perform stack alignment
2929 before the first push (the last arg). */
2930 if (PUSH_ARGS_REVERSED && argblock == 0
2931 && adjusted_args_size.constant != unadjusted_args_size)
2932 {
2933 /* When the stack adjustment is pending, we get better code
2934 by combining the adjustments. */
2935 if (pending_stack_adjust
2936 && ! inhibit_defer_pop)
2937 {
2938 pending_stack_adjust
2939 = (combine_pending_stack_adjustment_and_call
2940 (unadjusted_args_size,
2941 &adjusted_args_size,
2942 preferred_unit_stack_boundary));
2943 do_pending_stack_adjust ();
2944 }
2945 else if (argblock == 0)
2946 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2947 - unadjusted_args_size));
2948 }
2949 /* Now that the stack is properly aligned, pops can't safely
2950 be deferred during the evaluation of the arguments. */
2951 NO_DEFER_POP;
2952
2953 /* Record the maximum pushed stack space size. We need to delay
2954 doing it this far to take into account the optimization done
2955 by combine_pending_stack_adjustment_and_call. */
2956 if (flag_stack_usage_info
2957 && !ACCUMULATE_OUTGOING_ARGS
2958 && pass
2959 && adjusted_args_size.var == 0)
2960 {
2961 int pushed = adjusted_args_size.constant + pending_stack_adjust;
2962 if (pushed > current_function_pushed_stack_size)
2963 current_function_pushed_stack_size = pushed;
2964 }
2965
2966 funexp = rtx_for_function_call (fndecl, addr);
2967
2968 /* Figure out the register where the value, if any, will come back. */
2969 valreg = 0;
2970 if (TYPE_MODE (rettype) != VOIDmode
2971 && ! structure_value_addr)
2972 {
2973 if (pcc_struct_value)
2974 valreg = hard_function_value (build_pointer_type (rettype),
2975 fndecl, NULL, (pass == 0));
2976 else
2977 valreg = hard_function_value (rettype, fndecl, fntype,
2978 (pass == 0));
2979
2980 /* If VALREG is a PARALLEL whose first member has a zero
2981 offset, use that. This is for targets such as m68k that
2982 return the same value in multiple places. */
2983 if (GET_CODE (valreg) == PARALLEL)
2984 {
2985 rtx elem = XVECEXP (valreg, 0, 0);
2986 rtx where = XEXP (elem, 0);
2987 rtx offset = XEXP (elem, 1);
2988 if (offset == const0_rtx
2989 && GET_MODE (where) == GET_MODE (valreg))
2990 valreg = where;
2991 }
2992 }
2993
2994 /* Precompute all register parameters. It isn't safe to compute anything
2995 once we have started filling any specific hard regs. */
2996 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2997
2998 if (CALL_EXPR_STATIC_CHAIN (exp))
2999 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3000 else
3001 static_chain_value = 0;
3002
3003 #ifdef REG_PARM_STACK_SPACE
3004 /* Save the fixed argument area if it's part of the caller's frame and
3005 is clobbered by argument setup for this call. */
3006 if (ACCUMULATE_OUTGOING_ARGS && pass)
3007 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3008 &low_to_save, &high_to_save);
3009 #endif
3010
3011 /* Now store (and compute if necessary) all non-register parms.
3012 These come before register parms, since they can require block-moves,
3013 which could clobber the registers used for register parms.
3014 Parms which have partial registers are not stored here,
3015 but we do preallocate space here if they want that. */
3016
3017 for (i = 0; i < num_actuals; i++)
3018 {
3019 if (args[i].reg == 0 || args[i].pass_on_stack)
3020 {
3021 rtx before_arg = get_last_insn ();
3022
3023 if (store_one_arg (&args[i], argblock, flags,
3024 adjusted_args_size.var != 0,
3025 reg_parm_stack_space)
3026 || (pass == 0
3027 && check_sibcall_argument_overlap (before_arg,
3028 &args[i], 1)))
3029 sibcall_failure = 1;
3030 }
3031
3032 if (args[i].stack)
3033 call_fusage
3034 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3035 gen_rtx_USE (VOIDmode, args[i].stack),
3036 call_fusage);
3037 }
3038
3039 /* If we have a parm that is passed in registers but not in memory
3040 and whose alignment does not permit a direct copy into registers,
3041 make a group of pseudos that correspond to each register that we
3042 will later fill. */
3043 if (STRICT_ALIGNMENT)
3044 store_unaligned_arguments_into_pseudos (args, num_actuals);
3045
3046 /* Now store any partially-in-registers parm.
3047 This is the last place a block-move can happen. */
3048 if (reg_parm_seen)
3049 for (i = 0; i < num_actuals; i++)
3050 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3051 {
3052 rtx before_arg = get_last_insn ();
3053
3054 if (store_one_arg (&args[i], argblock, flags,
3055 adjusted_args_size.var != 0,
3056 reg_parm_stack_space)
3057 || (pass == 0
3058 && check_sibcall_argument_overlap (before_arg,
3059 &args[i], 1)))
3060 sibcall_failure = 1;
3061 }
3062
3063 /* If we pushed args in forward order, perform stack alignment
3064 after pushing the last arg. */
3065 if (!PUSH_ARGS_REVERSED && argblock == 0)
3066 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3067 - unadjusted_args_size));
3068
3069 /* If register arguments require space on the stack and stack space
3070 was not preallocated, allocate stack space here for arguments
3071 passed in registers. */
3072 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3073 && !ACCUMULATE_OUTGOING_ARGS
3074 && must_preallocate == 0 && reg_parm_stack_space > 0)
3075 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3076
3077 /* Pass the function the address in which to return a
3078 structure value. */
3079 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3080 {
3081 structure_value_addr
3082 = convert_memory_address (Pmode, structure_value_addr);
3083 emit_move_insn (struct_value,
3084 force_reg (Pmode,
3085 force_operand (structure_value_addr,
3086 NULL_RTX)));
3087
3088 if (REG_P (struct_value))
3089 use_reg (&call_fusage, struct_value);
3090 }
3091
3092 after_args = get_last_insn ();
3093 funexp = prepare_call_address (fndecl, funexp, static_chain_value,
3094 &call_fusage, reg_parm_seen, pass == 0);
3095
3096 load_register_parameters (args, num_actuals, &call_fusage, flags,
3097 pass == 0, &sibcall_failure);
3098
3099 /* Save a pointer to the last insn before the call, so that we can
3100 later safely search backwards to find the CALL_INSN. */
3101 before_call = get_last_insn ();
3102
3103 /* Set up next argument register. For sibling calls on machines
3104 with register windows this should be the incoming register. */
3105 if (pass == 0)
3106 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3107 VOIDmode,
3108 void_type_node,
3109 true);
3110 else
3111 next_arg_reg = targetm.calls.function_arg (args_so_far,
3112 VOIDmode, void_type_node,
3113 true);
3114
3115 /* All arguments and registers used for the call must be set up by
3116 now! */
3117
3118 /* Stack must be properly aligned now. */
3119 gcc_assert (!pass
3120 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3121
3122 /* Generate the actual call instruction. */
3123 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3124 adjusted_args_size.constant, struct_value_size,
3125 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3126 flags, args_so_far);
3127
3128 /* If the call setup or the call itself overlaps with anything
3129 of the argument setup we probably clobbered our call address.
3130 In that case we can't do sibcalls. */
3131 if (pass == 0
3132 && check_sibcall_argument_overlap (after_args, 0, 0))
3133 sibcall_failure = 1;
3134
3135 /* If a non-BLKmode value is returned at the most significant end
3136 of a register, shift the register right by the appropriate amount
3137 and update VALREG accordingly. BLKmode values are handled by the
3138 group load/store machinery below. */
3139 if (!structure_value_addr
3140 && !pcc_struct_value
3141 && TYPE_MODE (rettype) != BLKmode
3142 && targetm.calls.return_in_msb (rettype))
3143 {
3144 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3145 sibcall_failure = 1;
3146 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3147 }
3148
3149 if (pass && (flags & ECF_MALLOC))
3150 {
3151 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3152 rtx last, insns;
3153
3154 /* The return value from a malloc-like function is a pointer. */
3155 if (TREE_CODE (rettype) == POINTER_TYPE)
3156 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3157
3158 emit_move_insn (temp, valreg);
3159
3160 /* The return value from a malloc-like function can not alias
3161 anything else. */
3162 last = get_last_insn ();
3163 add_reg_note (last, REG_NOALIAS, temp);
3164
3165 /* Write out the sequence. */
3166 insns = get_insns ();
3167 end_sequence ();
3168 emit_insn (insns);
3169 valreg = temp;
3170 }
3171
3172 /* For calls to `setjmp', etc., inform
3173 function.c:setjmp_warnings that it should complain if
3174 nonvolatile values are live. For functions that cannot
3175 return, inform flow that control does not fall through. */
3176
3177 if ((flags & ECF_NORETURN) || pass == 0)
3178 {
3179 /* The barrier must be emitted
3180 immediately after the CALL_INSN. Some ports emit more
3181 than just a CALL_INSN above, so we must search for it here. */
3182
3183 rtx last = get_last_insn ();
3184 while (!CALL_P (last))
3185 {
3186 last = PREV_INSN (last);
3187 /* There was no CALL_INSN? */
3188 gcc_assert (last != before_call);
3189 }
3190
3191 emit_barrier_after (last);
3192
3193 /* Stack adjustments after a noreturn call are dead code.
3194 However when NO_DEFER_POP is in effect, we must preserve
3195 stack_pointer_delta. */
3196 if (inhibit_defer_pop == 0)
3197 {
3198 stack_pointer_delta = old_stack_allocated;
3199 pending_stack_adjust = 0;
3200 }
3201 }
3202
3203 /* If value type not void, return an rtx for the value. */
3204
3205 if (TYPE_MODE (rettype) == VOIDmode
3206 || ignore)
3207 target = const0_rtx;
3208 else if (structure_value_addr)
3209 {
3210 if (target == 0 || !MEM_P (target))
3211 {
3212 target
3213 = gen_rtx_MEM (TYPE_MODE (rettype),
3214 memory_address (TYPE_MODE (rettype),
3215 structure_value_addr));
3216 set_mem_attributes (target, rettype, 1);
3217 }
3218 }
3219 else if (pcc_struct_value)
3220 {
3221 /* This is the special C++ case where we need to
3222 know what the true target was. We take care to
3223 never use this value more than once in one expression. */
3224 target = gen_rtx_MEM (TYPE_MODE (rettype),
3225 copy_to_reg (valreg));
3226 set_mem_attributes (target, rettype, 1);
3227 }
3228 /* Handle calls that return values in multiple non-contiguous locations.
3229 The Irix 6 ABI has examples of this. */
3230 else if (GET_CODE (valreg) == PARALLEL)
3231 {
3232 if (target == 0)
3233 {
3234 /* This will only be assigned once, so it can be readonly. */
3235 tree nt = build_qualified_type (rettype,
3236 (TYPE_QUALS (rettype)
3237 | TYPE_QUAL_CONST));
3238
3239 target = assign_temp (nt, 0, 1, 1);
3240 }
3241
3242 if (! rtx_equal_p (target, valreg))
3243 emit_group_store (target, valreg, rettype,
3244 int_size_in_bytes (rettype));
3245
3246 /* We can not support sibling calls for this case. */
3247 sibcall_failure = 1;
3248 }
3249 else if (target
3250 && GET_MODE (target) == TYPE_MODE (rettype)
3251 && GET_MODE (target) == GET_MODE (valreg))
3252 {
3253 bool may_overlap = false;
3254
3255 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3256 reg to a plain register. */
3257 if (!REG_P (target) || HARD_REGISTER_P (target))
3258 valreg = avoid_likely_spilled_reg (valreg);
3259
3260 /* If TARGET is a MEM in the argument area, and we have
3261 saved part of the argument area, then we can't store
3262 directly into TARGET as it may get overwritten when we
3263 restore the argument save area below. Don't work too
3264 hard though and simply force TARGET to a register if it
3265 is a MEM; the optimizer is quite likely to sort it out. */
3266 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3267 for (i = 0; i < num_actuals; i++)
3268 if (args[i].save_area)
3269 {
3270 may_overlap = true;
3271 break;
3272 }
3273
3274 if (may_overlap)
3275 target = copy_to_reg (valreg);
3276 else
3277 {
3278 /* TARGET and VALREG cannot be equal at this point
3279 because the latter would not have
3280 REG_FUNCTION_VALUE_P true, while the former would if
3281 it were referring to the same register.
3282
3283 If they refer to the same register, this move will be
3284 a no-op, except when function inlining is being
3285 done. */
3286 emit_move_insn (target, valreg);
3287
3288 /* If we are setting a MEM, this code must be executed.
3289 Since it is emitted after the call insn, sibcall
3290 optimization cannot be performed in that case. */
3291 if (MEM_P (target))
3292 sibcall_failure = 1;
3293 }
3294 }
3295 else if (TYPE_MODE (rettype) == BLKmode)
3296 {
3297 rtx val = valreg;
3298 if (GET_MODE (val) != BLKmode)
3299 val = avoid_likely_spilled_reg (val);
3300 target = copy_blkmode_from_reg (target, val, rettype);
3301
3302 /* We can not support sibling calls for this case. */
3303 sibcall_failure = 1;
3304 }
3305 else
3306 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3307
3308 /* If we promoted this return value, make the proper SUBREG.
3309 TARGET might be const0_rtx here, so be careful. */
3310 if (REG_P (target)
3311 && TYPE_MODE (rettype) != BLKmode
3312 && GET_MODE (target) != TYPE_MODE (rettype))
3313 {
3314 tree type = rettype;
3315 int unsignedp = TYPE_UNSIGNED (type);
3316 int offset = 0;
3317 enum machine_mode pmode;
3318
3319 /* Ensure we promote as expected, and get the new unsignedness. */
3320 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3321 funtype, 1);
3322 gcc_assert (GET_MODE (target) == pmode);
3323
3324 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3325 && (GET_MODE_SIZE (GET_MODE (target))
3326 > GET_MODE_SIZE (TYPE_MODE (type))))
3327 {
3328 offset = GET_MODE_SIZE (GET_MODE (target))
3329 - GET_MODE_SIZE (TYPE_MODE (type));
3330 if (! BYTES_BIG_ENDIAN)
3331 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3332 else if (! WORDS_BIG_ENDIAN)
3333 offset %= UNITS_PER_WORD;
3334 }
3335
3336 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3337 SUBREG_PROMOTED_VAR_P (target) = 1;
3338 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3339 }
3340
3341 /* If size of args is variable or this was a constructor call for a stack
3342 argument, restore saved stack-pointer value. */
3343
3344 if (old_stack_level)
3345 {
3346 rtx prev = get_last_insn ();
3347
3348 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3349 stack_pointer_delta = old_stack_pointer_delta;
3350
3351 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3352
3353 pending_stack_adjust = old_pending_adj;
3354 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3355 stack_arg_under_construction = old_stack_arg_under_construction;
3356 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3357 stack_usage_map = initial_stack_usage_map;
3358 sibcall_failure = 1;
3359 }
3360 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3361 {
3362 #ifdef REG_PARM_STACK_SPACE
3363 if (save_area)
3364 restore_fixed_argument_area (save_area, argblock,
3365 high_to_save, low_to_save);
3366 #endif
3367
3368 /* If we saved any argument areas, restore them. */
3369 for (i = 0; i < num_actuals; i++)
3370 if (args[i].save_area)
3371 {
3372 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3373 rtx stack_area
3374 = gen_rtx_MEM (save_mode,
3375 memory_address (save_mode,
3376 XEXP (args[i].stack_slot, 0)));
3377
3378 if (save_mode != BLKmode)
3379 emit_move_insn (stack_area, args[i].save_area);
3380 else
3381 emit_block_move (stack_area, args[i].save_area,
3382 GEN_INT (args[i].locate.size.constant),
3383 BLOCK_OP_CALL_PARM);
3384 }
3385
3386 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3387 stack_usage_map = initial_stack_usage_map;
3388 }
3389
3390 /* If this was alloca, record the new stack level for nonlocal gotos.
3391 Check for the handler slots since we might not have a save area
3392 for non-local gotos. */
3393
3394 if ((flags & ECF_MAY_BE_ALLOCA) && cfun->nonlocal_goto_save_area != 0)
3395 update_nonlocal_goto_save_area ();
3396
3397 /* Free up storage we no longer need. */
3398 for (i = 0; i < num_actuals; ++i)
3399 free (args[i].aligned_regs);
3400
3401 insns = get_insns ();
3402 end_sequence ();
3403
3404 if (pass == 0)
3405 {
3406 tail_call_insns = insns;
3407
3408 /* Restore the pending stack adjustment now that we have
3409 finished generating the sibling call sequence. */
3410
3411 pending_stack_adjust = save_pending_stack_adjust;
3412 stack_pointer_delta = save_stack_pointer_delta;
3413
3414 /* Prepare arg structure for next iteration. */
3415 for (i = 0; i < num_actuals; i++)
3416 {
3417 args[i].value = 0;
3418 args[i].aligned_regs = 0;
3419 args[i].stack = 0;
3420 }
3421
3422 sbitmap_free (stored_args_map);
3423 internal_arg_pointer_exp_state.scan_start = NULL_RTX;
3424 VEC_free (rtx, heap, internal_arg_pointer_exp_state.cache);
3425 }
3426 else
3427 {
3428 normal_call_insns = insns;
3429
3430 /* Verify that we've deallocated all the stack we used. */
3431 gcc_assert ((flags & ECF_NORETURN)
3432 || (old_stack_allocated
3433 == stack_pointer_delta - pending_stack_adjust));
3434 }
3435
3436 /* If something prevents making this a sibling call,
3437 zero out the sequence. */
3438 if (sibcall_failure)
3439 tail_call_insns = NULL_RTX;
3440 else
3441 break;
3442 }
3443
3444 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3445 arguments too, as argument area is now clobbered by the call. */
3446 if (tail_call_insns)
3447 {
3448 emit_insn (tail_call_insns);
3449 crtl->tail_call_emit = true;
3450 }
3451 else
3452 emit_insn (normal_call_insns);
3453
3454 currently_expanding_call--;
3455
3456 free (stack_usage_map_buf);
3457
3458 return target;
3459 }
3460
3461 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3462 this function's incoming arguments.
3463
3464 At the start of RTL generation we know the only REG_EQUIV notes
3465 in the rtl chain are those for incoming arguments, so we can look
3466 for REG_EQUIV notes between the start of the function and the
3467 NOTE_INSN_FUNCTION_BEG.
3468
3469 This is (slight) overkill. We could keep track of the highest
3470 argument we clobber and be more selective in removing notes, but it
3471 does not seem to be worth the effort. */
3472
3473 void
fixup_tail_calls(void)3474 fixup_tail_calls (void)
3475 {
3476 rtx insn;
3477
3478 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3479 {
3480 rtx note;
3481
3482 /* There are never REG_EQUIV notes for the incoming arguments
3483 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3484 if (NOTE_P (insn)
3485 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3486 break;
3487
3488 note = find_reg_note (insn, REG_EQUIV, 0);
3489 if (note)
3490 remove_note (insn, note);
3491 note = find_reg_note (insn, REG_EQUIV, 0);
3492 gcc_assert (!note);
3493 }
3494 }
3495
3496 /* Traverse a list of TYPES and expand all complex types into their
3497 components. */
3498 static tree
split_complex_types(tree types)3499 split_complex_types (tree types)
3500 {
3501 tree p;
3502
3503 /* Before allocating memory, check for the common case of no complex. */
3504 for (p = types; p; p = TREE_CHAIN (p))
3505 {
3506 tree type = TREE_VALUE (p);
3507 if (TREE_CODE (type) == COMPLEX_TYPE
3508 && targetm.calls.split_complex_arg (type))
3509 goto found;
3510 }
3511 return types;
3512
3513 found:
3514 types = copy_list (types);
3515
3516 for (p = types; p; p = TREE_CHAIN (p))
3517 {
3518 tree complex_type = TREE_VALUE (p);
3519
3520 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3521 && targetm.calls.split_complex_arg (complex_type))
3522 {
3523 tree next, imag;
3524
3525 /* Rewrite complex type with component type. */
3526 TREE_VALUE (p) = TREE_TYPE (complex_type);
3527 next = TREE_CHAIN (p);
3528
3529 /* Add another component type for the imaginary part. */
3530 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3531 TREE_CHAIN (p) = imag;
3532 TREE_CHAIN (imag) = next;
3533
3534 /* Skip the newly created node. */
3535 p = TREE_CHAIN (p);
3536 }
3537 }
3538
3539 return types;
3540 }
3541
3542 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3543 The RETVAL parameter specifies whether return value needs to be saved, other
3544 parameters are documented in the emit_library_call function below. */
3545
3546 static rtx
emit_library_call_value_1(int retval,rtx orgfun,rtx value,enum libcall_type fn_type,enum machine_mode outmode,int nargs,va_list p)3547 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3548 enum libcall_type fn_type,
3549 enum machine_mode outmode, int nargs, va_list p)
3550 {
3551 /* Total size in bytes of all the stack-parms scanned so far. */
3552 struct args_size args_size;
3553 /* Size of arguments before any adjustments (such as rounding). */
3554 struct args_size original_args_size;
3555 int argnum;
3556 rtx fun;
3557 /* Todo, choose the correct decl type of orgfun. Sadly this information
3558 isn't present here, so we default to native calling abi here. */
3559 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3560 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3561 int inc;
3562 int count;
3563 rtx argblock = 0;
3564 CUMULATIVE_ARGS args_so_far_v;
3565 cumulative_args_t args_so_far;
3566 struct arg
3567 {
3568 rtx value;
3569 enum machine_mode mode;
3570 rtx reg;
3571 int partial;
3572 struct locate_and_pad_arg_data locate;
3573 rtx save_area;
3574 };
3575 struct arg *argvec;
3576 int old_inhibit_defer_pop = inhibit_defer_pop;
3577 rtx call_fusage = 0;
3578 rtx mem_value = 0;
3579 rtx valreg;
3580 int pcc_struct_value = 0;
3581 int struct_value_size = 0;
3582 int flags;
3583 int reg_parm_stack_space = 0;
3584 int needed;
3585 rtx before_call;
3586 tree tfom; /* type_for_mode (outmode, 0) */
3587
3588 #ifdef REG_PARM_STACK_SPACE
3589 /* Define the boundary of the register parm stack space that needs to be
3590 save, if any. */
3591 int low_to_save = 0, high_to_save = 0;
3592 rtx save_area = 0; /* Place that it is saved. */
3593 #endif
3594
3595 /* Size of the stack reserved for parameter registers. */
3596 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3597 char *initial_stack_usage_map = stack_usage_map;
3598 char *stack_usage_map_buf = NULL;
3599
3600 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3601
3602 #ifdef REG_PARM_STACK_SPACE
3603 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3604 #endif
3605
3606 /* By default, library functions can not throw. */
3607 flags = ECF_NOTHROW;
3608
3609 switch (fn_type)
3610 {
3611 case LCT_NORMAL:
3612 break;
3613 case LCT_CONST:
3614 flags |= ECF_CONST;
3615 break;
3616 case LCT_PURE:
3617 flags |= ECF_PURE;
3618 break;
3619 case LCT_NORETURN:
3620 flags |= ECF_NORETURN;
3621 break;
3622 case LCT_THROW:
3623 flags = ECF_NORETURN;
3624 break;
3625 case LCT_RETURNS_TWICE:
3626 flags = ECF_RETURNS_TWICE;
3627 break;
3628 }
3629 fun = orgfun;
3630
3631 /* Ensure current function's preferred stack boundary is at least
3632 what we need. */
3633 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3634 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3635
3636 /* If this kind of value comes back in memory,
3637 decide where in memory it should come back. */
3638 if (outmode != VOIDmode)
3639 {
3640 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3641 if (aggregate_value_p (tfom, 0))
3642 {
3643 #ifdef PCC_STATIC_STRUCT_RETURN
3644 rtx pointer_reg
3645 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3646 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3647 pcc_struct_value = 1;
3648 if (value == 0)
3649 value = gen_reg_rtx (outmode);
3650 #else /* not PCC_STATIC_STRUCT_RETURN */
3651 struct_value_size = GET_MODE_SIZE (outmode);
3652 if (value != 0 && MEM_P (value))
3653 mem_value = value;
3654 else
3655 mem_value = assign_temp (tfom, 0, 1, 1);
3656 #endif
3657 /* This call returns a big structure. */
3658 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3659 }
3660 }
3661 else
3662 tfom = void_type_node;
3663
3664 /* ??? Unfinished: must pass the memory address as an argument. */
3665
3666 /* Copy all the libcall-arguments out of the varargs data
3667 and into a vector ARGVEC.
3668
3669 Compute how to pass each argument. We only support a very small subset
3670 of the full argument passing conventions to limit complexity here since
3671 library functions shouldn't have many args. */
3672
3673 argvec = XALLOCAVEC (struct arg, nargs + 1);
3674 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3675
3676 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3677 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3678 #else
3679 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3680 #endif
3681 args_so_far = pack_cumulative_args (&args_so_far_v);
3682
3683 args_size.constant = 0;
3684 args_size.var = 0;
3685
3686 count = 0;
3687
3688 push_temp_slots ();
3689
3690 /* If there's a structure value address to be passed,
3691 either pass it in the special place, or pass it as an extra argument. */
3692 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3693 {
3694 rtx addr = XEXP (mem_value, 0);
3695
3696 nargs++;
3697
3698 /* Make sure it is a reasonable operand for a move or push insn. */
3699 if (!REG_P (addr) && !MEM_P (addr)
3700 && !(CONSTANT_P (addr)
3701 && targetm.legitimate_constant_p (Pmode, addr)))
3702 addr = force_operand (addr, NULL_RTX);
3703
3704 argvec[count].value = addr;
3705 argvec[count].mode = Pmode;
3706 argvec[count].partial = 0;
3707
3708 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3709 Pmode, NULL_TREE, true);
3710 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3711 NULL_TREE, 1) == 0);
3712
3713 locate_and_pad_parm (Pmode, NULL_TREE,
3714 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3715 1,
3716 #else
3717 argvec[count].reg != 0,
3718 #endif
3719 0, NULL_TREE, &args_size, &argvec[count].locate);
3720
3721 if (argvec[count].reg == 0 || argvec[count].partial != 0
3722 || reg_parm_stack_space > 0)
3723 args_size.constant += argvec[count].locate.size.constant;
3724
3725 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3726
3727 count++;
3728 }
3729
3730 for (; count < nargs; count++)
3731 {
3732 rtx val = va_arg (p, rtx);
3733 enum machine_mode mode = (enum machine_mode) va_arg (p, int);
3734 int unsigned_p = 0;
3735
3736 /* We cannot convert the arg value to the mode the library wants here;
3737 must do it earlier where we know the signedness of the arg. */
3738 gcc_assert (mode != BLKmode
3739 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3740
3741 /* Make sure it is a reasonable operand for a move or push insn. */
3742 if (!REG_P (val) && !MEM_P (val)
3743 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3744 val = force_operand (val, NULL_RTX);
3745
3746 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3747 {
3748 rtx slot;
3749 int must_copy
3750 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3751
3752 /* If this was a CONST function, it is now PURE since it now
3753 reads memory. */
3754 if (flags & ECF_CONST)
3755 {
3756 flags &= ~ECF_CONST;
3757 flags |= ECF_PURE;
3758 }
3759
3760 if (MEM_P (val) && !must_copy)
3761 {
3762 tree val_expr = MEM_EXPR (val);
3763 if (val_expr)
3764 mark_addressable (val_expr);
3765 slot = val;
3766 }
3767 else
3768 {
3769 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3770 0, 1, 1);
3771 emit_move_insn (slot, val);
3772 }
3773
3774 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3775 gen_rtx_USE (VOIDmode, slot),
3776 call_fusage);
3777 if (must_copy)
3778 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3779 gen_rtx_CLOBBER (VOIDmode,
3780 slot),
3781 call_fusage);
3782
3783 mode = Pmode;
3784 val = force_operand (XEXP (slot, 0), NULL_RTX);
3785 }
3786
3787 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
3788 argvec[count].mode = mode;
3789 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
3790 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
3791 NULL_TREE, true);
3792
3793 argvec[count].partial
3794 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
3795
3796 if (argvec[count].reg == 0
3797 || argvec[count].partial != 0
3798 || reg_parm_stack_space > 0)
3799 {
3800 locate_and_pad_parm (mode, NULL_TREE,
3801 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3802 1,
3803 #else
3804 argvec[count].reg != 0,
3805 #endif
3806 argvec[count].partial,
3807 NULL_TREE, &args_size, &argvec[count].locate);
3808 args_size.constant += argvec[count].locate.size.constant;
3809 gcc_assert (!argvec[count].locate.size.var);
3810 }
3811 #ifdef BLOCK_REG_PADDING
3812 else
3813 /* The argument is passed entirely in registers. See at which
3814 end it should be padded. */
3815 argvec[count].locate.where_pad =
3816 BLOCK_REG_PADDING (mode, NULL_TREE,
3817 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
3818 #endif
3819
3820 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
3821 }
3822
3823 /* If this machine requires an external definition for library
3824 functions, write one out. */
3825 assemble_external_libcall (fun);
3826
3827 original_args_size = args_size;
3828 args_size.constant = (((args_size.constant
3829 + stack_pointer_delta
3830 + STACK_BYTES - 1)
3831 / STACK_BYTES
3832 * STACK_BYTES)
3833 - stack_pointer_delta);
3834
3835 args_size.constant = MAX (args_size.constant,
3836 reg_parm_stack_space);
3837
3838 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3839 args_size.constant -= reg_parm_stack_space;
3840
3841 if (args_size.constant > crtl->outgoing_args_size)
3842 crtl->outgoing_args_size = args_size.constant;
3843
3844 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
3845 {
3846 int pushed = args_size.constant + pending_stack_adjust;
3847 if (pushed > current_function_pushed_stack_size)
3848 current_function_pushed_stack_size = pushed;
3849 }
3850
3851 if (ACCUMULATE_OUTGOING_ARGS)
3852 {
3853 /* Since the stack pointer will never be pushed, it is possible for
3854 the evaluation of a parm to clobber something we have already
3855 written to the stack. Since most function calls on RISC machines
3856 do not use the stack, this is uncommon, but must work correctly.
3857
3858 Therefore, we save any area of the stack that was already written
3859 and that we are using. Here we set up to do this by making a new
3860 stack usage map from the old one.
3861
3862 Another approach might be to try to reorder the argument
3863 evaluations to avoid this conflicting stack usage. */
3864
3865 needed = args_size.constant;
3866
3867 /* Since we will be writing into the entire argument area, the
3868 map must be allocated for its entire size, not just the part that
3869 is the responsibility of the caller. */
3870 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3871 needed += reg_parm_stack_space;
3872
3873 #ifdef ARGS_GROW_DOWNWARD
3874 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3875 needed + 1);
3876 #else
3877 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3878 needed);
3879 #endif
3880 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3881 stack_usage_map = stack_usage_map_buf;
3882
3883 if (initial_highest_arg_in_use)
3884 memcpy (stack_usage_map, initial_stack_usage_map,
3885 initial_highest_arg_in_use);
3886
3887 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3888 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3889 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3890 needed = 0;
3891
3892 /* We must be careful to use virtual regs before they're instantiated,
3893 and real regs afterwards. Loop optimization, for example, can create
3894 new libcalls after we've instantiated the virtual regs, and if we
3895 use virtuals anyway, they won't match the rtl patterns. */
3896
3897 if (virtuals_instantiated)
3898 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3899 else
3900 argblock = virtual_outgoing_args_rtx;
3901 }
3902 else
3903 {
3904 if (!PUSH_ARGS)
3905 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3906 }
3907
3908 /* If we push args individually in reverse order, perform stack alignment
3909 before the first push (the last arg). */
3910 if (argblock == 0 && PUSH_ARGS_REVERSED)
3911 anti_adjust_stack (GEN_INT (args_size.constant
3912 - original_args_size.constant));
3913
3914 if (PUSH_ARGS_REVERSED)
3915 {
3916 inc = -1;
3917 argnum = nargs - 1;
3918 }
3919 else
3920 {
3921 inc = 1;
3922 argnum = 0;
3923 }
3924
3925 #ifdef REG_PARM_STACK_SPACE
3926 if (ACCUMULATE_OUTGOING_ARGS)
3927 {
3928 /* The argument list is the property of the called routine and it
3929 may clobber it. If the fixed area has been used for previous
3930 parameters, we must save and restore it. */
3931 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3932 &low_to_save, &high_to_save);
3933 }
3934 #endif
3935
3936 /* Push the args that need to be pushed. */
3937
3938 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3939 are to be pushed. */
3940 for (count = 0; count < nargs; count++, argnum += inc)
3941 {
3942 enum machine_mode mode = argvec[argnum].mode;
3943 rtx val = argvec[argnum].value;
3944 rtx reg = argvec[argnum].reg;
3945 int partial = argvec[argnum].partial;
3946 unsigned int parm_align = argvec[argnum].locate.boundary;
3947 int lower_bound = 0, upper_bound = 0, i;
3948
3949 if (! (reg != 0 && partial == 0))
3950 {
3951 rtx use;
3952
3953 if (ACCUMULATE_OUTGOING_ARGS)
3954 {
3955 /* If this is being stored into a pre-allocated, fixed-size,
3956 stack area, save any previous data at that location. */
3957
3958 #ifdef ARGS_GROW_DOWNWARD
3959 /* stack_slot is negative, but we want to index stack_usage_map
3960 with positive values. */
3961 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
3962 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3963 #else
3964 lower_bound = argvec[argnum].locate.slot_offset.constant;
3965 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3966 #endif
3967
3968 i = lower_bound;
3969 /* Don't worry about things in the fixed argument area;
3970 it has already been saved. */
3971 if (i < reg_parm_stack_space)
3972 i = reg_parm_stack_space;
3973 while (i < upper_bound && stack_usage_map[i] == 0)
3974 i++;
3975
3976 if (i < upper_bound)
3977 {
3978 /* We need to make a save area. */
3979 unsigned int size
3980 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
3981 enum machine_mode save_mode
3982 = mode_for_size (size, MODE_INT, 1);
3983 rtx adr
3984 = plus_constant (argblock,
3985 argvec[argnum].locate.offset.constant);
3986 rtx stack_area
3987 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
3988
3989 if (save_mode == BLKmode)
3990 {
3991 argvec[argnum].save_area
3992 = assign_stack_temp (BLKmode,
3993 argvec[argnum].locate.size.constant,
3994 0);
3995
3996 emit_block_move (validize_mem (argvec[argnum].save_area),
3997 stack_area,
3998 GEN_INT (argvec[argnum].locate.size.constant),
3999 BLOCK_OP_CALL_PARM);
4000 }
4001 else
4002 {
4003 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4004
4005 emit_move_insn (argvec[argnum].save_area, stack_area);
4006 }
4007 }
4008 }
4009
4010 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4011 partial, reg, 0, argblock,
4012 GEN_INT (argvec[argnum].locate.offset.constant),
4013 reg_parm_stack_space,
4014 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4015
4016 /* Now mark the segment we just used. */
4017 if (ACCUMULATE_OUTGOING_ARGS)
4018 for (i = lower_bound; i < upper_bound; i++)
4019 stack_usage_map[i] = 1;
4020
4021 NO_DEFER_POP;
4022
4023 /* Indicate argument access so that alias.c knows that these
4024 values are live. */
4025 if (argblock)
4026 use = plus_constant (argblock,
4027 argvec[argnum].locate.offset.constant);
4028 else
4029 /* When arguments are pushed, trying to tell alias.c where
4030 exactly this argument is won't work, because the
4031 auto-increment causes confusion. So we merely indicate
4032 that we access something with a known mode somewhere on
4033 the stack. */
4034 use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
4035 gen_rtx_SCRATCH (Pmode));
4036 use = gen_rtx_MEM (argvec[argnum].mode, use);
4037 use = gen_rtx_USE (VOIDmode, use);
4038 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4039 }
4040 }
4041
4042 /* If we pushed args in forward order, perform stack alignment
4043 after pushing the last arg. */
4044 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4045 anti_adjust_stack (GEN_INT (args_size.constant
4046 - original_args_size.constant));
4047
4048 if (PUSH_ARGS_REVERSED)
4049 argnum = nargs - 1;
4050 else
4051 argnum = 0;
4052
4053 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4054
4055 /* Now load any reg parms into their regs. */
4056
4057 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4058 are to be pushed. */
4059 for (count = 0; count < nargs; count++, argnum += inc)
4060 {
4061 enum machine_mode mode = argvec[argnum].mode;
4062 rtx val = argvec[argnum].value;
4063 rtx reg = argvec[argnum].reg;
4064 int partial = argvec[argnum].partial;
4065 #ifdef BLOCK_REG_PADDING
4066 int size = 0;
4067 #endif
4068
4069 /* Handle calls that pass values in multiple non-contiguous
4070 locations. The PA64 has examples of this for library calls. */
4071 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4072 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4073 else if (reg != 0 && partial == 0)
4074 {
4075 emit_move_insn (reg, val);
4076 #ifdef BLOCK_REG_PADDING
4077 size = GET_MODE_SIZE (argvec[argnum].mode);
4078
4079 /* Copied from load_register_parameters. */
4080
4081 /* Handle case where we have a value that needs shifting
4082 up to the msb. eg. a QImode value and we're padding
4083 upward on a BYTES_BIG_ENDIAN machine. */
4084 if (size < UNITS_PER_WORD
4085 && (argvec[argnum].locate.where_pad
4086 == (BYTES_BIG_ENDIAN ? upward : downward)))
4087 {
4088 rtx x;
4089 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4090
4091 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4092 report the whole reg as used. Strictly speaking, the
4093 call only uses SIZE bytes at the msb end, but it doesn't
4094 seem worth generating rtl to say that. */
4095 reg = gen_rtx_REG (word_mode, REGNO (reg));
4096 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4097 if (x != reg)
4098 emit_move_insn (reg, x);
4099 }
4100 #endif
4101 }
4102
4103 NO_DEFER_POP;
4104 }
4105
4106 /* Any regs containing parms remain in use through the call. */
4107 for (count = 0; count < nargs; count++)
4108 {
4109 rtx reg = argvec[count].reg;
4110 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4111 use_group_regs (&call_fusage, reg);
4112 else if (reg != 0)
4113 {
4114 int partial = argvec[count].partial;
4115 if (partial)
4116 {
4117 int nregs;
4118 gcc_assert (partial % UNITS_PER_WORD == 0);
4119 nregs = partial / UNITS_PER_WORD;
4120 use_regs (&call_fusage, REGNO (reg), nregs);
4121 }
4122 else
4123 use_reg (&call_fusage, reg);
4124 }
4125 }
4126
4127 /* Pass the function the address in which to return a structure value. */
4128 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4129 {
4130 emit_move_insn (struct_value,
4131 force_reg (Pmode,
4132 force_operand (XEXP (mem_value, 0),
4133 NULL_RTX)));
4134 if (REG_P (struct_value))
4135 use_reg (&call_fusage, struct_value);
4136 }
4137
4138 /* Don't allow popping to be deferred, since then
4139 cse'ing of library calls could delete a call and leave the pop. */
4140 NO_DEFER_POP;
4141 valreg = (mem_value == 0 && outmode != VOIDmode
4142 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4143
4144 /* Stack must be properly aligned now. */
4145 gcc_assert (!(stack_pointer_delta
4146 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4147
4148 before_call = get_last_insn ();
4149
4150 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4151 will set inhibit_defer_pop to that value. */
4152 /* The return type is needed to decide how many bytes the function pops.
4153 Signedness plays no role in that, so for simplicity, we pretend it's
4154 always signed. We also assume that the list of arguments passed has
4155 no impact, so we pretend it is unknown. */
4156
4157 emit_call_1 (fun, NULL,
4158 get_identifier (XSTR (orgfun, 0)),
4159 build_function_type (tfom, NULL_TREE),
4160 original_args_size.constant, args_size.constant,
4161 struct_value_size,
4162 targetm.calls.function_arg (args_so_far,
4163 VOIDmode, void_type_node, true),
4164 valreg,
4165 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4166
4167 /* Right-shift returned value if necessary. */
4168 if (!pcc_struct_value
4169 && TYPE_MODE (tfom) != BLKmode
4170 && targetm.calls.return_in_msb (tfom))
4171 {
4172 shift_return_value (TYPE_MODE (tfom), false, valreg);
4173 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4174 }
4175
4176 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4177 that it should complain if nonvolatile values are live. For
4178 functions that cannot return, inform flow that control does not
4179 fall through. */
4180
4181 if (flags & ECF_NORETURN)
4182 {
4183 /* The barrier note must be emitted
4184 immediately after the CALL_INSN. Some ports emit more than
4185 just a CALL_INSN above, so we must search for it here. */
4186
4187 rtx last = get_last_insn ();
4188 while (!CALL_P (last))
4189 {
4190 last = PREV_INSN (last);
4191 /* There was no CALL_INSN? */
4192 gcc_assert (last != before_call);
4193 }
4194
4195 emit_barrier_after (last);
4196 }
4197
4198 /* Now restore inhibit_defer_pop to its actual original value. */
4199 OK_DEFER_POP;
4200
4201 pop_temp_slots ();
4202
4203 /* Copy the value to the right place. */
4204 if (outmode != VOIDmode && retval)
4205 {
4206 if (mem_value)
4207 {
4208 if (value == 0)
4209 value = mem_value;
4210 if (value != mem_value)
4211 emit_move_insn (value, mem_value);
4212 }
4213 else if (GET_CODE (valreg) == PARALLEL)
4214 {
4215 if (value == 0)
4216 value = gen_reg_rtx (outmode);
4217 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4218 }
4219 else
4220 {
4221 /* Convert to the proper mode if a promotion has been active. */
4222 if (GET_MODE (valreg) != outmode)
4223 {
4224 int unsignedp = TYPE_UNSIGNED (tfom);
4225
4226 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4227 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4228 == GET_MODE (valreg));
4229 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4230 }
4231
4232 if (value != 0)
4233 emit_move_insn (value, valreg);
4234 else
4235 value = valreg;
4236 }
4237 }
4238
4239 if (ACCUMULATE_OUTGOING_ARGS)
4240 {
4241 #ifdef REG_PARM_STACK_SPACE
4242 if (save_area)
4243 restore_fixed_argument_area (save_area, argblock,
4244 high_to_save, low_to_save);
4245 #endif
4246
4247 /* If we saved any argument areas, restore them. */
4248 for (count = 0; count < nargs; count++)
4249 if (argvec[count].save_area)
4250 {
4251 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4252 rtx adr = plus_constant (argblock,
4253 argvec[count].locate.offset.constant);
4254 rtx stack_area = gen_rtx_MEM (save_mode,
4255 memory_address (save_mode, adr));
4256
4257 if (save_mode == BLKmode)
4258 emit_block_move (stack_area,
4259 validize_mem (argvec[count].save_area),
4260 GEN_INT (argvec[count].locate.size.constant),
4261 BLOCK_OP_CALL_PARM);
4262 else
4263 emit_move_insn (stack_area, argvec[count].save_area);
4264 }
4265
4266 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4267 stack_usage_map = initial_stack_usage_map;
4268 }
4269
4270 free (stack_usage_map_buf);
4271
4272 return value;
4273
4274 }
4275
4276 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4277 (emitting the queue unless NO_QUEUE is nonzero),
4278 for a value of mode OUTMODE,
4279 with NARGS different arguments, passed as alternating rtx values
4280 and machine_modes to convert them to.
4281
4282 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4283 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4284 other types of library calls. */
4285
4286 void
emit_library_call(rtx orgfun,enum libcall_type fn_type,enum machine_mode outmode,int nargs,...)4287 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4288 enum machine_mode outmode, int nargs, ...)
4289 {
4290 va_list p;
4291
4292 va_start (p, nargs);
4293 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4294 va_end (p);
4295 }
4296
4297 /* Like emit_library_call except that an extra argument, VALUE,
4298 comes second and says where to store the result.
4299 (If VALUE is zero, this function chooses a convenient way
4300 to return the value.
4301
4302 This function returns an rtx for where the value is to be found.
4303 If VALUE is nonzero, VALUE is returned. */
4304
4305 rtx
emit_library_call_value(rtx orgfun,rtx value,enum libcall_type fn_type,enum machine_mode outmode,int nargs,...)4306 emit_library_call_value (rtx orgfun, rtx value,
4307 enum libcall_type fn_type,
4308 enum machine_mode outmode, int nargs, ...)
4309 {
4310 rtx result;
4311 va_list p;
4312
4313 va_start (p, nargs);
4314 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4315 nargs, p);
4316 va_end (p);
4317
4318 return result;
4319 }
4320
4321 /* Store a single argument for a function call
4322 into the register or memory area where it must be passed.
4323 *ARG describes the argument value and where to pass it.
4324
4325 ARGBLOCK is the address of the stack-block for all the arguments,
4326 or 0 on a machine where arguments are pushed individually.
4327
4328 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4329 so must be careful about how the stack is used.
4330
4331 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4332 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4333 that we need not worry about saving and restoring the stack.
4334
4335 FNDECL is the declaration of the function we are calling.
4336
4337 Return nonzero if this arg should cause sibcall failure,
4338 zero otherwise. */
4339
4340 static int
store_one_arg(struct arg_data * arg,rtx argblock,int flags,int variable_size ATTRIBUTE_UNUSED,int reg_parm_stack_space)4341 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4342 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4343 {
4344 tree pval = arg->tree_value;
4345 rtx reg = 0;
4346 int partial = 0;
4347 int used = 0;
4348 int i, lower_bound = 0, upper_bound = 0;
4349 int sibcall_failure = 0;
4350
4351 if (TREE_CODE (pval) == ERROR_MARK)
4352 return 1;
4353
4354 /* Push a new temporary level for any temporaries we make for
4355 this argument. */
4356 push_temp_slots ();
4357
4358 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4359 {
4360 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4361 save any previous data at that location. */
4362 if (argblock && ! variable_size && arg->stack)
4363 {
4364 #ifdef ARGS_GROW_DOWNWARD
4365 /* stack_slot is negative, but we want to index stack_usage_map
4366 with positive values. */
4367 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4368 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4369 else
4370 upper_bound = 0;
4371
4372 lower_bound = upper_bound - arg->locate.size.constant;
4373 #else
4374 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4375 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4376 else
4377 lower_bound = 0;
4378
4379 upper_bound = lower_bound + arg->locate.size.constant;
4380 #endif
4381
4382 i = lower_bound;
4383 /* Don't worry about things in the fixed argument area;
4384 it has already been saved. */
4385 if (i < reg_parm_stack_space)
4386 i = reg_parm_stack_space;
4387 while (i < upper_bound && stack_usage_map[i] == 0)
4388 i++;
4389
4390 if (i < upper_bound)
4391 {
4392 /* We need to make a save area. */
4393 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4394 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4395 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4396 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4397
4398 if (save_mode == BLKmode)
4399 {
4400 tree ot = TREE_TYPE (arg->tree_value);
4401 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4402 | TYPE_QUAL_CONST));
4403
4404 arg->save_area = assign_temp (nt, 0, 1, 1);
4405 preserve_temp_slots (arg->save_area);
4406 emit_block_move (validize_mem (arg->save_area), stack_area,
4407 GEN_INT (arg->locate.size.constant),
4408 BLOCK_OP_CALL_PARM);
4409 }
4410 else
4411 {
4412 arg->save_area = gen_reg_rtx (save_mode);
4413 emit_move_insn (arg->save_area, stack_area);
4414 }
4415 }
4416 }
4417 }
4418
4419 /* If this isn't going to be placed on both the stack and in registers,
4420 set up the register and number of words. */
4421 if (! arg->pass_on_stack)
4422 {
4423 if (flags & ECF_SIBCALL)
4424 reg = arg->tail_call_reg;
4425 else
4426 reg = arg->reg;
4427 partial = arg->partial;
4428 }
4429
4430 /* Being passed entirely in a register. We shouldn't be called in
4431 this case. */
4432 gcc_assert (reg == 0 || partial != 0);
4433
4434 /* If this arg needs special alignment, don't load the registers
4435 here. */
4436 if (arg->n_aligned_regs != 0)
4437 reg = 0;
4438
4439 /* If this is being passed partially in a register, we can't evaluate
4440 it directly into its stack slot. Otherwise, we can. */
4441 if (arg->value == 0)
4442 {
4443 /* stack_arg_under_construction is nonzero if a function argument is
4444 being evaluated directly into the outgoing argument list and
4445 expand_call must take special action to preserve the argument list
4446 if it is called recursively.
4447
4448 For scalar function arguments stack_usage_map is sufficient to
4449 determine which stack slots must be saved and restored. Scalar
4450 arguments in general have pass_on_stack == 0.
4451
4452 If this argument is initialized by a function which takes the
4453 address of the argument (a C++ constructor or a C function
4454 returning a BLKmode structure), then stack_usage_map is
4455 insufficient and expand_call must push the stack around the
4456 function call. Such arguments have pass_on_stack == 1.
4457
4458 Note that it is always safe to set stack_arg_under_construction,
4459 but this generates suboptimal code if set when not needed. */
4460
4461 if (arg->pass_on_stack)
4462 stack_arg_under_construction++;
4463
4464 arg->value = expand_expr (pval,
4465 (partial
4466 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4467 ? NULL_RTX : arg->stack,
4468 VOIDmode, EXPAND_STACK_PARM);
4469
4470 /* If we are promoting object (or for any other reason) the mode
4471 doesn't agree, convert the mode. */
4472
4473 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4474 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4475 arg->value, arg->unsignedp);
4476
4477 if (arg->pass_on_stack)
4478 stack_arg_under_construction--;
4479 }
4480
4481 /* Check for overlap with already clobbered argument area. */
4482 if ((flags & ECF_SIBCALL)
4483 && MEM_P (arg->value)
4484 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4485 arg->locate.size.constant))
4486 sibcall_failure = 1;
4487
4488 /* Don't allow anything left on stack from computation
4489 of argument to alloca. */
4490 if (flags & ECF_MAY_BE_ALLOCA)
4491 do_pending_stack_adjust ();
4492
4493 if (arg->value == arg->stack)
4494 /* If the value is already in the stack slot, we are done. */
4495 ;
4496 else if (arg->mode != BLKmode)
4497 {
4498 int size;
4499 unsigned int parm_align;
4500
4501 /* Argument is a scalar, not entirely passed in registers.
4502 (If part is passed in registers, arg->partial says how much
4503 and emit_push_insn will take care of putting it there.)
4504
4505 Push it, and if its size is less than the
4506 amount of space allocated to it,
4507 also bump stack pointer by the additional space.
4508 Note that in C the default argument promotions
4509 will prevent such mismatches. */
4510
4511 size = GET_MODE_SIZE (arg->mode);
4512 /* Compute how much space the push instruction will push.
4513 On many machines, pushing a byte will advance the stack
4514 pointer by a halfword. */
4515 #ifdef PUSH_ROUNDING
4516 size = PUSH_ROUNDING (size);
4517 #endif
4518 used = size;
4519
4520 /* Compute how much space the argument should get:
4521 round up to a multiple of the alignment for arguments. */
4522 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4523 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4524 / (PARM_BOUNDARY / BITS_PER_UNIT))
4525 * (PARM_BOUNDARY / BITS_PER_UNIT));
4526
4527 /* Compute the alignment of the pushed argument. */
4528 parm_align = arg->locate.boundary;
4529 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4530 {
4531 int pad = used - size;
4532 if (pad)
4533 {
4534 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4535 parm_align = MIN (parm_align, pad_align);
4536 }
4537 }
4538
4539 /* This isn't already where we want it on the stack, so put it there.
4540 This can either be done with push or copy insns. */
4541 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4542 parm_align, partial, reg, used - size, argblock,
4543 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4544 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4545
4546 /* Unless this is a partially-in-register argument, the argument is now
4547 in the stack. */
4548 if (partial == 0)
4549 arg->value = arg->stack;
4550 }
4551 else
4552 {
4553 /* BLKmode, at least partly to be pushed. */
4554
4555 unsigned int parm_align;
4556 int excess;
4557 rtx size_rtx;
4558
4559 /* Pushing a nonscalar.
4560 If part is passed in registers, PARTIAL says how much
4561 and emit_push_insn will take care of putting it there. */
4562
4563 /* Round its size up to a multiple
4564 of the allocation unit for arguments. */
4565
4566 if (arg->locate.size.var != 0)
4567 {
4568 excess = 0;
4569 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4570 }
4571 else
4572 {
4573 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4574 for BLKmode is careful to avoid it. */
4575 excess = (arg->locate.size.constant
4576 - int_size_in_bytes (TREE_TYPE (pval))
4577 + partial);
4578 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4579 NULL_RTX, TYPE_MODE (sizetype),
4580 EXPAND_NORMAL);
4581 }
4582
4583 parm_align = arg->locate.boundary;
4584
4585 /* When an argument is padded down, the block is aligned to
4586 PARM_BOUNDARY, but the actual argument isn't. */
4587 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4588 {
4589 if (arg->locate.size.var)
4590 parm_align = BITS_PER_UNIT;
4591 else if (excess)
4592 {
4593 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4594 parm_align = MIN (parm_align, excess_align);
4595 }
4596 }
4597
4598 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4599 {
4600 /* emit_push_insn might not work properly if arg->value and
4601 argblock + arg->locate.offset areas overlap. */
4602 rtx x = arg->value;
4603 int i = 0;
4604
4605 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4606 || (GET_CODE (XEXP (x, 0)) == PLUS
4607 && XEXP (XEXP (x, 0), 0) ==
4608 crtl->args.internal_arg_pointer
4609 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4610 {
4611 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4612 i = INTVAL (XEXP (XEXP (x, 0), 1));
4613
4614 /* expand_call should ensure this. */
4615 gcc_assert (!arg->locate.offset.var
4616 && arg->locate.size.var == 0
4617 && CONST_INT_P (size_rtx));
4618
4619 if (arg->locate.offset.constant > i)
4620 {
4621 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4622 sibcall_failure = 1;
4623 }
4624 else if (arg->locate.offset.constant < i)
4625 {
4626 /* Use arg->locate.size.constant instead of size_rtx
4627 because we only care about the part of the argument
4628 on the stack. */
4629 if (i < (arg->locate.offset.constant
4630 + arg->locate.size.constant))
4631 sibcall_failure = 1;
4632 }
4633 else
4634 {
4635 /* Even though they appear to be at the same location,
4636 if part of the outgoing argument is in registers,
4637 they aren't really at the same location. Check for
4638 this by making sure that the incoming size is the
4639 same as the outgoing size. */
4640 if (arg->locate.size.constant != INTVAL (size_rtx))
4641 sibcall_failure = 1;
4642 }
4643 }
4644 }
4645
4646 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4647 parm_align, partial, reg, excess, argblock,
4648 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4649 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4650
4651 /* Unless this is a partially-in-register argument, the argument is now
4652 in the stack.
4653
4654 ??? Unlike the case above, in which we want the actual
4655 address of the data, so that we can load it directly into a
4656 register, here we want the address of the stack slot, so that
4657 it's properly aligned for word-by-word copying or something
4658 like that. It's not clear that this is always correct. */
4659 if (partial == 0)
4660 arg->value = arg->stack_slot;
4661 }
4662
4663 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
4664 {
4665 tree type = TREE_TYPE (arg->tree_value);
4666 arg->parallel_value
4667 = emit_group_load_into_temps (arg->reg, arg->value, type,
4668 int_size_in_bytes (type));
4669 }
4670
4671 /* Mark all slots this store used. */
4672 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4673 && argblock && ! variable_size && arg->stack)
4674 for (i = lower_bound; i < upper_bound; i++)
4675 stack_usage_map[i] = 1;
4676
4677 /* Once we have pushed something, pops can't safely
4678 be deferred during the rest of the arguments. */
4679 NO_DEFER_POP;
4680
4681 /* Free any temporary slots made in processing this argument. Show
4682 that we might have taken the address of something and pushed that
4683 as an operand. */
4684 preserve_temp_slots (NULL_RTX);
4685 free_temp_slots ();
4686 pop_temp_slots ();
4687
4688 return sibcall_failure;
4689 }
4690
4691 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4692
4693 bool
must_pass_in_stack_var_size(enum machine_mode mode ATTRIBUTE_UNUSED,const_tree type)4694 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED,
4695 const_tree type)
4696 {
4697 if (!type)
4698 return false;
4699
4700 /* If the type has variable size... */
4701 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4702 return true;
4703
4704 /* If the type is marked as addressable (it is required
4705 to be constructed into the stack)... */
4706 if (TREE_ADDRESSABLE (type))
4707 return true;
4708
4709 return false;
4710 }
4711
4712 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4713 takes trailing padding of a structure into account. */
4714 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4715
4716 bool
must_pass_in_stack_var_size_or_pad(enum machine_mode mode,const_tree type)4717 must_pass_in_stack_var_size_or_pad (enum machine_mode mode, const_tree type)
4718 {
4719 if (!type)
4720 return false;
4721
4722 /* If the type has variable size... */
4723 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4724 return true;
4725
4726 /* If the type is marked as addressable (it is required
4727 to be constructed into the stack)... */
4728 if (TREE_ADDRESSABLE (type))
4729 return true;
4730
4731 /* If the padding and mode of the type is such that a copy into
4732 a register would put it into the wrong part of the register. */
4733 if (mode == BLKmode
4734 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4735 && (FUNCTION_ARG_PADDING (mode, type)
4736 == (BYTES_BIG_ENDIAN ? upward : downward)))
4737 return true;
4738
4739 return false;
4740 }
4741