* config/rl78/rl78-expand.md (umulqihi3): Disable for G10.
[official-gcc.git] / gcc / calls.c
blob4285ec1a6f189fa7567cc3a45956248ee934b85e
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "tm.h"
24 #include "rtl.h"
25 #include "tree.h"
26 #include "stor-layout.h"
27 #include "varasm.h"
28 #include "stringpool.h"
29 #include "attribs.h"
30 #include "basic-block.h"
31 #include "tree-ssa-alias.h"
32 #include "internal-fn.h"
33 #include "gimple-expr.h"
34 #include "is-a.h"
35 #include "gimple.h"
36 #include "flags.h"
37 #include "expr.h"
38 #include "optabs.h"
39 #include "libfuncs.h"
40 #include "function.h"
41 #include "regs.h"
42 #include "diagnostic-core.h"
43 #include "output.h"
44 #include "tm_p.h"
45 #include "timevar.h"
46 #include "sbitmap.h"
47 #include "langhooks.h"
48 #include "target.h"
49 #include "cgraph.h"
50 #include "except.h"
51 #include "dbgcnt.h"
53 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
54 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
56 /* Data structure and subroutines used within expand_call. */
58 struct arg_data
60 /* Tree node for this argument. */
61 tree tree_value;
62 /* Mode for value; TYPE_MODE unless promoted. */
63 enum machine_mode mode;
64 /* Current RTL value for argument, or 0 if it isn't precomputed. */
65 rtx value;
66 /* Initially-compute RTL value for argument; only for const functions. */
67 rtx initial_value;
68 /* Register to pass this argument in, 0 if passed on stack, or an
69 PARALLEL if the arg is to be copied into multiple non-contiguous
70 registers. */
71 rtx reg;
72 /* Register to pass this argument in when generating tail call sequence.
73 This is not the same register as for normal calls on machines with
74 register windows. */
75 rtx tail_call_reg;
76 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
77 form for emit_group_move. */
78 rtx parallel_value;
79 /* If REG was promoted from the actual mode of the argument expression,
80 indicates whether the promotion is sign- or zero-extended. */
81 int unsignedp;
82 /* Number of bytes to put in registers. 0 means put the whole arg
83 in registers. Also 0 if not passed in registers. */
84 int partial;
85 /* Nonzero if argument must be passed on stack.
86 Note that some arguments may be passed on the stack
87 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
88 pass_on_stack identifies arguments that *cannot* go in registers. */
89 int pass_on_stack;
90 /* Some fields packaged up for locate_and_pad_parm. */
91 struct locate_and_pad_arg_data locate;
92 /* Location on the stack at which parameter should be stored. The store
93 has already been done if STACK == VALUE. */
94 rtx stack;
95 /* Location on the stack of the start of this argument slot. This can
96 differ from STACK if this arg pads downward. This location is known
97 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
98 rtx stack_slot;
99 /* Place that this stack area has been saved, if needed. */
100 rtx save_area;
101 /* If an argument's alignment does not permit direct copying into registers,
102 copy in smaller-sized pieces into pseudos. These are stored in a
103 block pointed to by this field. The next field says how many
104 word-sized pseudos we made. */
105 rtx *aligned_regs;
106 int n_aligned_regs;
109 /* A vector of one char per byte of stack space. A byte if nonzero if
110 the corresponding stack location has been used.
111 This vector is used to prevent a function call within an argument from
112 clobbering any stack already set up. */
113 static char *stack_usage_map;
115 /* Size of STACK_USAGE_MAP. */
116 static int highest_outgoing_arg_in_use;
118 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
119 stack location's tail call argument has been already stored into the stack.
120 This bitmap is used to prevent sibling call optimization if function tries
121 to use parent's incoming argument slots when they have been already
122 overwritten with tail call arguments. */
123 static sbitmap stored_args_map;
125 /* stack_arg_under_construction is nonzero when an argument may be
126 initialized with a constructor call (including a C function that
127 returns a BLKmode struct) and expand_call must take special action
128 to make sure the object being constructed does not overlap the
129 argument list for the constructor call. */
130 static int stack_arg_under_construction;
132 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
133 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
134 cumulative_args_t);
135 static void precompute_register_parameters (int, struct arg_data *, int *);
136 static int store_one_arg (struct arg_data *, rtx, int, int, int);
137 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
138 static int finalize_must_preallocate (int, int, struct arg_data *,
139 struct args_size *);
140 static void precompute_arguments (int, struct arg_data *);
141 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
142 static void initialize_argument_information (int, struct arg_data *,
143 struct args_size *, int,
144 tree, tree,
145 tree, tree, cumulative_args_t, int,
146 rtx *, int *, int *, int *,
147 bool *, bool);
148 static void compute_argument_addresses (struct arg_data *, rtx, int);
149 static rtx rtx_for_function_call (tree, tree);
150 static void load_register_parameters (struct arg_data *, int, rtx *, int,
151 int, int *);
152 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
153 enum machine_mode, int, va_list);
154 static int special_function_p (const_tree, int);
155 static int check_sibcall_argument_overlap_1 (rtx);
156 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
158 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
159 unsigned int);
160 static tree split_complex_types (tree);
162 #ifdef REG_PARM_STACK_SPACE
163 static rtx save_fixed_argument_area (int, rtx, int *, int *);
164 static void restore_fixed_argument_area (rtx, rtx, int, int);
165 #endif
167 /* Force FUNEXP into a form suitable for the address of a CALL,
168 and return that as an rtx. Also load the static chain register
169 if FNDECL is a nested function.
171 CALL_FUSAGE points to a variable holding the prospective
172 CALL_INSN_FUNCTION_USAGE information. */
175 prepare_call_address (tree fndecl, rtx funexp, rtx static_chain_value,
176 rtx *call_fusage, int reg_parm_seen, int sibcallp)
178 /* Make a valid memory address and copy constants through pseudo-regs,
179 but not for a constant address if -fno-function-cse. */
180 if (GET_CODE (funexp) != SYMBOL_REF)
181 /* If we are using registers for parameters, force the
182 function address into a register now. */
183 funexp = ((reg_parm_seen
184 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
185 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
186 : memory_address (FUNCTION_MODE, funexp));
187 else if (! sibcallp)
189 #ifndef NO_FUNCTION_CSE
190 if (optimize && ! flag_no_function_cse)
191 funexp = force_reg (Pmode, funexp);
192 #endif
195 if (static_chain_value != 0)
197 rtx chain;
199 gcc_assert (fndecl);
200 chain = targetm.calls.static_chain (fndecl, false);
201 static_chain_value = convert_memory_address (Pmode, static_chain_value);
203 emit_move_insn (chain, static_chain_value);
204 if (REG_P (chain))
205 use_reg (call_fusage, chain);
208 return funexp;
211 /* Generate instructions to call function FUNEXP,
212 and optionally pop the results.
213 The CALL_INSN is the first insn generated.
215 FNDECL is the declaration node of the function. This is given to the
216 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
217 its own args.
219 FUNTYPE is the data type of the function. This is given to the hook
220 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
221 own args. We used to allow an identifier for library functions, but
222 that doesn't work when the return type is an aggregate type and the
223 calling convention says that the pointer to this aggregate is to be
224 popped by the callee.
226 STACK_SIZE is the number of bytes of arguments on the stack,
227 ROUNDED_STACK_SIZE is that number rounded up to
228 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
229 both to put into the call insn and to generate explicit popping
230 code if necessary.
232 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
233 It is zero if this call doesn't want a structure value.
235 NEXT_ARG_REG is the rtx that results from executing
236 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
237 just after all the args have had their registers assigned.
238 This could be whatever you like, but normally it is the first
239 arg-register beyond those used for args in this call,
240 or 0 if all the arg-registers are used in this call.
241 It is passed on to `gen_call' so you can put this info in the call insn.
243 VALREG is a hard register in which a value is returned,
244 or 0 if the call does not return a value.
246 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
247 the args to this call were processed.
248 We restore `inhibit_defer_pop' to that value.
250 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
251 denote registers used by the called function. */
253 static void
254 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
255 tree funtype ATTRIBUTE_UNUSED,
256 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
257 HOST_WIDE_INT rounded_stack_size,
258 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
259 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
260 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
261 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
263 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
264 rtx call_insn, call, funmem;
265 int already_popped = 0;
266 HOST_WIDE_INT n_popped
267 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
269 #ifdef CALL_POPS_ARGS
270 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
271 #endif
273 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
274 and we don't want to load it into a register as an optimization,
275 because prepare_call_address already did it if it should be done. */
276 if (GET_CODE (funexp) != SYMBOL_REF)
277 funexp = memory_address (FUNCTION_MODE, funexp);
279 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
280 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
282 tree t = fndecl;
284 /* Although a built-in FUNCTION_DECL and its non-__builtin
285 counterpart compare equal and get a shared mem_attrs, they
286 produce different dump output in compare-debug compilations,
287 if an entry gets garbage collected in one compilation, then
288 adds a different (but equivalent) entry, while the other
289 doesn't run the garbage collector at the same spot and then
290 shares the mem_attr with the equivalent entry. */
291 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
293 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
294 if (t2)
295 t = t2;
298 set_mem_expr (funmem, t);
300 else if (fntree)
301 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
303 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
304 if ((ecf_flags & ECF_SIBCALL)
305 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
306 && (n_popped > 0 || stack_size == 0))
308 rtx n_pop = GEN_INT (n_popped);
309 rtx pat;
311 /* If this subroutine pops its own args, record that in the call insn
312 if possible, for the sake of frame pointer elimination. */
314 if (valreg)
315 pat = GEN_SIBCALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
316 next_arg_reg, n_pop);
317 else
318 pat = GEN_SIBCALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
319 n_pop);
321 emit_call_insn (pat);
322 already_popped = 1;
324 else
325 #endif
327 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
328 /* If the target has "call" or "call_value" insns, then prefer them
329 if no arguments are actually popped. If the target does not have
330 "call" or "call_value" insns, then we must use the popping versions
331 even if the call has no arguments to pop. */
332 #if defined (HAVE_call) && defined (HAVE_call_value)
333 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
334 && n_popped > 0)
335 #else
336 if (HAVE_call_pop && HAVE_call_value_pop)
337 #endif
339 rtx n_pop = GEN_INT (n_popped);
340 rtx pat;
342 /* If this subroutine pops its own args, record that in the call insn
343 if possible, for the sake of frame pointer elimination. */
345 if (valreg)
346 pat = GEN_CALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
347 next_arg_reg, n_pop);
348 else
349 pat = GEN_CALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
350 n_pop);
352 emit_call_insn (pat);
353 already_popped = 1;
355 else
356 #endif
358 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
359 if ((ecf_flags & ECF_SIBCALL)
360 && HAVE_sibcall && HAVE_sibcall_value)
362 if (valreg)
363 emit_call_insn (GEN_SIBCALL_VALUE (valreg, funmem,
364 rounded_stack_size_rtx,
365 next_arg_reg, NULL_RTX));
366 else
367 emit_call_insn (GEN_SIBCALL (funmem, rounded_stack_size_rtx,
368 next_arg_reg,
369 GEN_INT (struct_value_size)));
371 else
372 #endif
374 #if defined (HAVE_call) && defined (HAVE_call_value)
375 if (HAVE_call && HAVE_call_value)
377 if (valreg)
378 emit_call_insn (GEN_CALL_VALUE (valreg, funmem, rounded_stack_size_rtx,
379 next_arg_reg, NULL_RTX));
380 else
381 emit_call_insn (GEN_CALL (funmem, rounded_stack_size_rtx, next_arg_reg,
382 GEN_INT (struct_value_size)));
384 else
385 #endif
386 gcc_unreachable ();
388 /* Find the call we just emitted. */
389 call_insn = last_call_insn ();
391 /* Some target create a fresh MEM instead of reusing the one provided
392 above. Set its MEM_EXPR. */
393 call = get_call_rtx_from (call_insn);
394 if (call
395 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
396 && MEM_EXPR (funmem) != NULL_TREE)
397 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
399 /* Put the register usage information there. */
400 add_function_usage_to (call_insn, call_fusage);
402 /* If this is a const call, then set the insn's unchanging bit. */
403 if (ecf_flags & ECF_CONST)
404 RTL_CONST_CALL_P (call_insn) = 1;
406 /* If this is a pure call, then set the insn's unchanging bit. */
407 if (ecf_flags & ECF_PURE)
408 RTL_PURE_CALL_P (call_insn) = 1;
410 /* If this is a const call, then set the insn's unchanging bit. */
411 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
412 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
414 /* Create a nothrow REG_EH_REGION note, if needed. */
415 make_reg_eh_region_note (call_insn, ecf_flags, 0);
417 if (ecf_flags & ECF_NORETURN)
418 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
420 if (ecf_flags & ECF_RETURNS_TWICE)
422 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
423 cfun->calls_setjmp = 1;
426 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
428 /* Restore this now, so that we do defer pops for this call's args
429 if the context of the call as a whole permits. */
430 inhibit_defer_pop = old_inhibit_defer_pop;
432 if (n_popped > 0)
434 if (!already_popped)
435 CALL_INSN_FUNCTION_USAGE (call_insn)
436 = gen_rtx_EXPR_LIST (VOIDmode,
437 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
438 CALL_INSN_FUNCTION_USAGE (call_insn));
439 rounded_stack_size -= n_popped;
440 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
441 stack_pointer_delta -= n_popped;
443 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
445 /* If popup is needed, stack realign must use DRAP */
446 if (SUPPORTS_STACK_ALIGNMENT)
447 crtl->need_drap = true;
449 /* For noreturn calls when not accumulating outgoing args force
450 REG_ARGS_SIZE note to prevent crossjumping of calls with different
451 args sizes. */
452 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
453 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
455 if (!ACCUMULATE_OUTGOING_ARGS)
457 /* If returning from the subroutine does not automatically pop the args,
458 we need an instruction to pop them sooner or later.
459 Perhaps do it now; perhaps just record how much space to pop later.
461 If returning from the subroutine does pop the args, indicate that the
462 stack pointer will be changed. */
464 if (rounded_stack_size != 0)
466 if (ecf_flags & ECF_NORETURN)
467 /* Just pretend we did the pop. */
468 stack_pointer_delta -= rounded_stack_size;
469 else if (flag_defer_pop && inhibit_defer_pop == 0
470 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
471 pending_stack_adjust += rounded_stack_size;
472 else
473 adjust_stack (rounded_stack_size_rtx);
476 /* When we accumulate outgoing args, we must avoid any stack manipulations.
477 Restore the stack pointer to its original value now. Usually
478 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
479 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
480 popping variants of functions exist as well.
482 ??? We may optimize similar to defer_pop above, but it is
483 probably not worthwhile.
485 ??? It will be worthwhile to enable combine_stack_adjustments even for
486 such machines. */
487 else if (n_popped)
488 anti_adjust_stack (GEN_INT (n_popped));
491 /* Determine if the function identified by NAME and FNDECL is one with
492 special properties we wish to know about.
494 For example, if the function might return more than one time (setjmp), then
495 set RETURNS_TWICE to a nonzero value.
497 Similarly set NORETURN if the function is in the longjmp family.
499 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
500 space from the stack such as alloca. */
502 static int
503 special_function_p (const_tree fndecl, int flags)
505 if (fndecl && DECL_NAME (fndecl)
506 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
507 /* Exclude functions not at the file scope, or not `extern',
508 since they are not the magic functions we would otherwise
509 think they are.
510 FIXME: this should be handled with attributes, not with this
511 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
512 because you can declare fork() inside a function if you
513 wish. */
514 && (DECL_CONTEXT (fndecl) == NULL_TREE
515 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
516 && TREE_PUBLIC (fndecl))
518 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
519 const char *tname = name;
521 /* We assume that alloca will always be called by name. It
522 makes no sense to pass it as a pointer-to-function to
523 anything that does not understand its behavior. */
524 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
525 && name[0] == 'a'
526 && ! strcmp (name, "alloca"))
527 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
528 && name[0] == '_'
529 && ! strcmp (name, "__builtin_alloca"))))
530 flags |= ECF_MAY_BE_ALLOCA;
532 /* Disregard prefix _, __, __x or __builtin_. */
533 if (name[0] == '_')
535 if (name[1] == '_'
536 && name[2] == 'b'
537 && !strncmp (name + 3, "uiltin_", 7))
538 tname += 10;
539 else if (name[1] == '_' && name[2] == 'x')
540 tname += 3;
541 else if (name[1] == '_')
542 tname += 2;
543 else
544 tname += 1;
547 if (tname[0] == 's')
549 if ((tname[1] == 'e'
550 && (! strcmp (tname, "setjmp")
551 || ! strcmp (tname, "setjmp_syscall")))
552 || (tname[1] == 'i'
553 && ! strcmp (tname, "sigsetjmp"))
554 || (tname[1] == 'a'
555 && ! strcmp (tname, "savectx")))
556 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
558 if (tname[1] == 'i'
559 && ! strcmp (tname, "siglongjmp"))
560 flags |= ECF_NORETURN;
562 else if ((tname[0] == 'q' && tname[1] == 's'
563 && ! strcmp (tname, "qsetjmp"))
564 || (tname[0] == 'v' && tname[1] == 'f'
565 && ! strcmp (tname, "vfork"))
566 || (tname[0] == 'g' && tname[1] == 'e'
567 && !strcmp (tname, "getcontext")))
568 flags |= ECF_RETURNS_TWICE | ECF_LEAF;
570 else if (tname[0] == 'l' && tname[1] == 'o'
571 && ! strcmp (tname, "longjmp"))
572 flags |= ECF_NORETURN;
575 return flags;
578 /* Similar to special_function_p; return a set of ERF_ flags for the
579 function FNDECL. */
580 static int
581 decl_return_flags (tree fndecl)
583 tree attr;
584 tree type = TREE_TYPE (fndecl);
585 if (!type)
586 return 0;
588 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
589 if (!attr)
590 return 0;
592 attr = TREE_VALUE (TREE_VALUE (attr));
593 if (!attr || TREE_STRING_LENGTH (attr) < 1)
594 return 0;
596 switch (TREE_STRING_POINTER (attr)[0])
598 case '1':
599 case '2':
600 case '3':
601 case '4':
602 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
604 case 'm':
605 return ERF_NOALIAS;
607 case '.':
608 default:
609 return 0;
613 /* Return nonzero when FNDECL represents a call to setjmp. */
616 setjmp_call_p (const_tree fndecl)
618 if (DECL_IS_RETURNS_TWICE (fndecl))
619 return ECF_RETURNS_TWICE;
620 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
624 /* Return true if STMT is an alloca call. */
626 bool
627 gimple_alloca_call_p (const_gimple stmt)
629 tree fndecl;
631 if (!is_gimple_call (stmt))
632 return false;
634 fndecl = gimple_call_fndecl (stmt);
635 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
636 return true;
638 return false;
641 /* Return true when exp contains alloca call. */
643 bool
644 alloca_call_p (const_tree exp)
646 tree fndecl;
647 if (TREE_CODE (exp) == CALL_EXPR
648 && (fndecl = get_callee_fndecl (exp))
649 && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
650 return true;
651 return false;
654 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
655 function. Return FALSE otherwise. */
657 static bool
658 is_tm_builtin (const_tree fndecl)
660 if (fndecl == NULL)
661 return false;
663 if (decl_is_tm_clone (fndecl))
664 return true;
666 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
668 switch (DECL_FUNCTION_CODE (fndecl))
670 case BUILT_IN_TM_COMMIT:
671 case BUILT_IN_TM_COMMIT_EH:
672 case BUILT_IN_TM_ABORT:
673 case BUILT_IN_TM_IRREVOCABLE:
674 case BUILT_IN_TM_GETTMCLONE_IRR:
675 case BUILT_IN_TM_MEMCPY:
676 case BUILT_IN_TM_MEMMOVE:
677 case BUILT_IN_TM_MEMSET:
678 CASE_BUILT_IN_TM_STORE (1):
679 CASE_BUILT_IN_TM_STORE (2):
680 CASE_BUILT_IN_TM_STORE (4):
681 CASE_BUILT_IN_TM_STORE (8):
682 CASE_BUILT_IN_TM_STORE (FLOAT):
683 CASE_BUILT_IN_TM_STORE (DOUBLE):
684 CASE_BUILT_IN_TM_STORE (LDOUBLE):
685 CASE_BUILT_IN_TM_STORE (M64):
686 CASE_BUILT_IN_TM_STORE (M128):
687 CASE_BUILT_IN_TM_STORE (M256):
688 CASE_BUILT_IN_TM_LOAD (1):
689 CASE_BUILT_IN_TM_LOAD (2):
690 CASE_BUILT_IN_TM_LOAD (4):
691 CASE_BUILT_IN_TM_LOAD (8):
692 CASE_BUILT_IN_TM_LOAD (FLOAT):
693 CASE_BUILT_IN_TM_LOAD (DOUBLE):
694 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
695 CASE_BUILT_IN_TM_LOAD (M64):
696 CASE_BUILT_IN_TM_LOAD (M128):
697 CASE_BUILT_IN_TM_LOAD (M256):
698 case BUILT_IN_TM_LOG:
699 case BUILT_IN_TM_LOG_1:
700 case BUILT_IN_TM_LOG_2:
701 case BUILT_IN_TM_LOG_4:
702 case BUILT_IN_TM_LOG_8:
703 case BUILT_IN_TM_LOG_FLOAT:
704 case BUILT_IN_TM_LOG_DOUBLE:
705 case BUILT_IN_TM_LOG_LDOUBLE:
706 case BUILT_IN_TM_LOG_M64:
707 case BUILT_IN_TM_LOG_M128:
708 case BUILT_IN_TM_LOG_M256:
709 return true;
710 default:
711 break;
714 return false;
717 /* Detect flags (function attributes) from the function decl or type node. */
720 flags_from_decl_or_type (const_tree exp)
722 int flags = 0;
724 if (DECL_P (exp))
726 /* The function exp may have the `malloc' attribute. */
727 if (DECL_IS_MALLOC (exp))
728 flags |= ECF_MALLOC;
730 /* The function exp may have the `returns_twice' attribute. */
731 if (DECL_IS_RETURNS_TWICE (exp))
732 flags |= ECF_RETURNS_TWICE;
734 /* Process the pure and const attributes. */
735 if (TREE_READONLY (exp))
736 flags |= ECF_CONST;
737 if (DECL_PURE_P (exp))
738 flags |= ECF_PURE;
739 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
740 flags |= ECF_LOOPING_CONST_OR_PURE;
742 if (DECL_IS_NOVOPS (exp))
743 flags |= ECF_NOVOPS;
744 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
745 flags |= ECF_LEAF;
747 if (TREE_NOTHROW (exp))
748 flags |= ECF_NOTHROW;
750 if (flag_tm)
752 if (is_tm_builtin (exp))
753 flags |= ECF_TM_BUILTIN;
754 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
755 || lookup_attribute ("transaction_pure",
756 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
757 flags |= ECF_TM_PURE;
760 flags = special_function_p (exp, flags);
762 else if (TYPE_P (exp))
764 if (TYPE_READONLY (exp))
765 flags |= ECF_CONST;
767 if (flag_tm
768 && ((flags & ECF_CONST) != 0
769 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
770 flags |= ECF_TM_PURE;
772 else
773 gcc_unreachable ();
775 if (TREE_THIS_VOLATILE (exp))
777 flags |= ECF_NORETURN;
778 if (flags & (ECF_CONST|ECF_PURE))
779 flags |= ECF_LOOPING_CONST_OR_PURE;
782 return flags;
785 /* Detect flags from a CALL_EXPR. */
788 call_expr_flags (const_tree t)
790 int flags;
791 tree decl = get_callee_fndecl (t);
793 if (decl)
794 flags = flags_from_decl_or_type (decl);
795 else
797 t = TREE_TYPE (CALL_EXPR_FN (t));
798 if (t && TREE_CODE (t) == POINTER_TYPE)
799 flags = flags_from_decl_or_type (TREE_TYPE (t));
800 else
801 flags = 0;
804 return flags;
807 /* Precompute all register parameters as described by ARGS, storing values
808 into fields within the ARGS array.
810 NUM_ACTUALS indicates the total number elements in the ARGS array.
812 Set REG_PARM_SEEN if we encounter a register parameter. */
814 static void
815 precompute_register_parameters (int num_actuals, struct arg_data *args,
816 int *reg_parm_seen)
818 int i;
820 *reg_parm_seen = 0;
822 for (i = 0; i < num_actuals; i++)
823 if (args[i].reg != 0 && ! args[i].pass_on_stack)
825 *reg_parm_seen = 1;
827 if (args[i].value == 0)
829 push_temp_slots ();
830 args[i].value = expand_normal (args[i].tree_value);
831 preserve_temp_slots (args[i].value);
832 pop_temp_slots ();
835 /* If we are to promote the function arg to a wider mode,
836 do it now. */
838 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
839 args[i].value
840 = convert_modes (args[i].mode,
841 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
842 args[i].value, args[i].unsignedp);
844 /* If the value is a non-legitimate constant, force it into a
845 pseudo now. TLS symbols sometimes need a call to resolve. */
846 if (CONSTANT_P (args[i].value)
847 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
848 args[i].value = force_reg (args[i].mode, args[i].value);
850 /* If we're going to have to load the value by parts, pull the
851 parts into pseudos. The part extraction process can involve
852 non-trivial computation. */
853 if (GET_CODE (args[i].reg) == PARALLEL)
855 tree type = TREE_TYPE (args[i].tree_value);
856 args[i].parallel_value
857 = emit_group_load_into_temps (args[i].reg, args[i].value,
858 type, int_size_in_bytes (type));
861 /* If the value is expensive, and we are inside an appropriately
862 short loop, put the value into a pseudo and then put the pseudo
863 into the hard reg.
865 For small register classes, also do this if this call uses
866 register parameters. This is to avoid reload conflicts while
867 loading the parameters registers. */
869 else if ((! (REG_P (args[i].value)
870 || (GET_CODE (args[i].value) == SUBREG
871 && REG_P (SUBREG_REG (args[i].value)))))
872 && args[i].mode != BLKmode
873 && set_src_cost (args[i].value, optimize_insn_for_speed_p ())
874 > COSTS_N_INSNS (1)
875 && ((*reg_parm_seen
876 && targetm.small_register_classes_for_mode_p (args[i].mode))
877 || optimize))
878 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
882 #ifdef REG_PARM_STACK_SPACE
884 /* The argument list is the property of the called routine and it
885 may clobber it. If the fixed area has been used for previous
886 parameters, we must save and restore it. */
888 static rtx
889 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
891 int low;
892 int high;
894 /* Compute the boundary of the area that needs to be saved, if any. */
895 high = reg_parm_stack_space;
896 #ifdef ARGS_GROW_DOWNWARD
897 high += 1;
898 #endif
899 if (high > highest_outgoing_arg_in_use)
900 high = highest_outgoing_arg_in_use;
902 for (low = 0; low < high; low++)
903 if (stack_usage_map[low] != 0)
905 int num_to_save;
906 enum machine_mode save_mode;
907 int delta;
908 rtx addr;
909 rtx stack_area;
910 rtx save_area;
912 while (stack_usage_map[--high] == 0)
915 *low_to_save = low;
916 *high_to_save = high;
918 num_to_save = high - low + 1;
919 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
921 /* If we don't have the required alignment, must do this
922 in BLKmode. */
923 if ((low & (MIN (GET_MODE_SIZE (save_mode),
924 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
925 save_mode = BLKmode;
927 #ifdef ARGS_GROW_DOWNWARD
928 delta = -high;
929 #else
930 delta = low;
931 #endif
932 addr = plus_constant (Pmode, argblock, delta);
933 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
935 set_mem_align (stack_area, PARM_BOUNDARY);
936 if (save_mode == BLKmode)
938 save_area = assign_stack_temp (BLKmode, num_to_save);
939 emit_block_move (validize_mem (save_area), stack_area,
940 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
942 else
944 save_area = gen_reg_rtx (save_mode);
945 emit_move_insn (save_area, stack_area);
948 return save_area;
951 return NULL_RTX;
954 static void
955 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
957 enum machine_mode save_mode = GET_MODE (save_area);
958 int delta;
959 rtx addr, stack_area;
961 #ifdef ARGS_GROW_DOWNWARD
962 delta = -high_to_save;
963 #else
964 delta = low_to_save;
965 #endif
966 addr = plus_constant (Pmode, argblock, delta);
967 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
968 set_mem_align (stack_area, PARM_BOUNDARY);
970 if (save_mode != BLKmode)
971 emit_move_insn (stack_area, save_area);
972 else
973 emit_block_move (stack_area, validize_mem (save_area),
974 GEN_INT (high_to_save - low_to_save + 1),
975 BLOCK_OP_CALL_PARM);
977 #endif /* REG_PARM_STACK_SPACE */
979 /* If any elements in ARGS refer to parameters that are to be passed in
980 registers, but not in memory, and whose alignment does not permit a
981 direct copy into registers. Copy the values into a group of pseudos
982 which we will later copy into the appropriate hard registers.
984 Pseudos for each unaligned argument will be stored into the array
985 args[argnum].aligned_regs. The caller is responsible for deallocating
986 the aligned_regs array if it is nonzero. */
988 static void
989 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
991 int i, j;
993 for (i = 0; i < num_actuals; i++)
994 if (args[i].reg != 0 && ! args[i].pass_on_stack
995 && GET_CODE (args[i].reg) != PARALLEL
996 && args[i].mode == BLKmode
997 && MEM_P (args[i].value)
998 && (MEM_ALIGN (args[i].value)
999 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1001 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1002 int endian_correction = 0;
1004 if (args[i].partial)
1006 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1007 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1009 else
1011 args[i].n_aligned_regs
1012 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1015 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1017 /* Structures smaller than a word are normally aligned to the
1018 least significant byte. On a BYTES_BIG_ENDIAN machine,
1019 this means we must skip the empty high order bytes when
1020 calculating the bit offset. */
1021 if (bytes < UNITS_PER_WORD
1022 #ifdef BLOCK_REG_PADDING
1023 && (BLOCK_REG_PADDING (args[i].mode,
1024 TREE_TYPE (args[i].tree_value), 1)
1025 == downward)
1026 #else
1027 && BYTES_BIG_ENDIAN
1028 #endif
1030 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1032 for (j = 0; j < args[i].n_aligned_regs; j++)
1034 rtx reg = gen_reg_rtx (word_mode);
1035 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1036 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1038 args[i].aligned_regs[j] = reg;
1039 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1040 word_mode, word_mode);
1042 /* There is no need to restrict this code to loading items
1043 in TYPE_ALIGN sized hunks. The bitfield instructions can
1044 load up entire word sized registers efficiently.
1046 ??? This may not be needed anymore.
1047 We use to emit a clobber here but that doesn't let later
1048 passes optimize the instructions we emit. By storing 0 into
1049 the register later passes know the first AND to zero out the
1050 bitfield being set in the register is unnecessary. The store
1051 of 0 will be deleted as will at least the first AND. */
1053 emit_move_insn (reg, const0_rtx);
1055 bytes -= bitsize / BITS_PER_UNIT;
1056 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1057 word_mode, word);
1062 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1063 CALL_EXPR EXP.
1065 NUM_ACTUALS is the total number of parameters.
1067 N_NAMED_ARGS is the total number of named arguments.
1069 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1070 value, or null.
1072 FNDECL is the tree code for the target of this call (if known)
1074 ARGS_SO_FAR holds state needed by the target to know where to place
1075 the next argument.
1077 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1078 for arguments which are passed in registers.
1080 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1081 and may be modified by this routine.
1083 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1084 flags which may may be modified by this routine.
1086 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1087 that requires allocation of stack space.
1089 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1090 the thunked-to function. */
1092 static void
1093 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1094 struct arg_data *args,
1095 struct args_size *args_size,
1096 int n_named_args ATTRIBUTE_UNUSED,
1097 tree exp, tree struct_value_addr_value,
1098 tree fndecl, tree fntype,
1099 cumulative_args_t args_so_far,
1100 int reg_parm_stack_space,
1101 rtx *old_stack_level, int *old_pending_adj,
1102 int *must_preallocate, int *ecf_flags,
1103 bool *may_tailcall, bool call_from_thunk_p)
1105 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1106 location_t loc = EXPR_LOCATION (exp);
1108 /* Count arg position in order args appear. */
1109 int argpos;
1111 int i;
1113 args_size->constant = 0;
1114 args_size->var = 0;
1116 /* In this loop, we consider args in the order they are written.
1117 We fill up ARGS from the back. */
1119 i = num_actuals - 1;
1121 int j = i;
1122 call_expr_arg_iterator iter;
1123 tree arg;
1125 if (struct_value_addr_value)
1127 args[j].tree_value = struct_value_addr_value;
1128 j--;
1130 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1132 tree argtype = TREE_TYPE (arg);
1133 if (targetm.calls.split_complex_arg
1134 && argtype
1135 && TREE_CODE (argtype) == COMPLEX_TYPE
1136 && targetm.calls.split_complex_arg (argtype))
1138 tree subtype = TREE_TYPE (argtype);
1139 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1140 j--;
1141 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1143 else
1144 args[j].tree_value = arg;
1145 j--;
1149 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1150 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1152 tree type = TREE_TYPE (args[i].tree_value);
1153 int unsignedp;
1154 enum machine_mode mode;
1156 /* Replace erroneous argument with constant zero. */
1157 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1158 args[i].tree_value = integer_zero_node, type = integer_type_node;
1160 /* If TYPE is a transparent union or record, pass things the way
1161 we would pass the first field of the union or record. We have
1162 already verified that the modes are the same. */
1163 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1164 && TYPE_TRANSPARENT_AGGR (type))
1165 type = TREE_TYPE (first_field (type));
1167 /* Decide where to pass this arg.
1169 args[i].reg is nonzero if all or part is passed in registers.
1171 args[i].partial is nonzero if part but not all is passed in registers,
1172 and the exact value says how many bytes are passed in registers.
1174 args[i].pass_on_stack is nonzero if the argument must at least be
1175 computed on the stack. It may then be loaded back into registers
1176 if args[i].reg is nonzero.
1178 These decisions are driven by the FUNCTION_... macros and must agree
1179 with those made by function.c. */
1181 /* See if this argument should be passed by invisible reference. */
1182 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1183 type, argpos < n_named_args))
1185 bool callee_copies;
1186 tree base = NULL_TREE;
1188 callee_copies
1189 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1190 type, argpos < n_named_args);
1192 /* If we're compiling a thunk, pass through invisible references
1193 instead of making a copy. */
1194 if (call_from_thunk_p
1195 || (callee_copies
1196 && !TREE_ADDRESSABLE (type)
1197 && (base = get_base_address (args[i].tree_value))
1198 && TREE_CODE (base) != SSA_NAME
1199 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1201 mark_addressable (args[i].tree_value);
1203 /* We can't use sibcalls if a callee-copied argument is
1204 stored in the current function's frame. */
1205 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1206 *may_tailcall = false;
1208 args[i].tree_value = build_fold_addr_expr_loc (loc,
1209 args[i].tree_value);
1210 type = TREE_TYPE (args[i].tree_value);
1212 if (*ecf_flags & ECF_CONST)
1213 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1215 else
1217 /* We make a copy of the object and pass the address to the
1218 function being called. */
1219 rtx copy;
1221 if (!COMPLETE_TYPE_P (type)
1222 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1223 || (flag_stack_check == GENERIC_STACK_CHECK
1224 && compare_tree_int (TYPE_SIZE_UNIT (type),
1225 STACK_CHECK_MAX_VAR_SIZE) > 0))
1227 /* This is a variable-sized object. Make space on the stack
1228 for it. */
1229 rtx size_rtx = expr_size (args[i].tree_value);
1231 if (*old_stack_level == 0)
1233 emit_stack_save (SAVE_BLOCK, old_stack_level);
1234 *old_pending_adj = pending_stack_adjust;
1235 pending_stack_adjust = 0;
1238 /* We can pass TRUE as the 4th argument because we just
1239 saved the stack pointer and will restore it right after
1240 the call. */
1241 copy = allocate_dynamic_stack_space (size_rtx,
1242 TYPE_ALIGN (type),
1243 TYPE_ALIGN (type),
1244 true);
1245 copy = gen_rtx_MEM (BLKmode, copy);
1246 set_mem_attributes (copy, type, 1);
1248 else
1249 copy = assign_temp (type, 1, 0);
1251 store_expr (args[i].tree_value, copy, 0, false);
1253 /* Just change the const function to pure and then let
1254 the next test clear the pure based on
1255 callee_copies. */
1256 if (*ecf_flags & ECF_CONST)
1258 *ecf_flags &= ~ECF_CONST;
1259 *ecf_flags |= ECF_PURE;
1262 if (!callee_copies && *ecf_flags & ECF_PURE)
1263 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1265 args[i].tree_value
1266 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1267 type = TREE_TYPE (args[i].tree_value);
1268 *may_tailcall = false;
1272 unsignedp = TYPE_UNSIGNED (type);
1273 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1274 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1276 args[i].unsignedp = unsignedp;
1277 args[i].mode = mode;
1279 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1280 argpos < n_named_args);
1282 /* If this is a sibling call and the machine has register windows, the
1283 register window has to be unwinded before calling the routine, so
1284 arguments have to go into the incoming registers. */
1285 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1286 args[i].tail_call_reg
1287 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1288 argpos < n_named_args);
1289 else
1290 args[i].tail_call_reg = args[i].reg;
1292 if (args[i].reg)
1293 args[i].partial
1294 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1295 argpos < n_named_args);
1297 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1299 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1300 it means that we are to pass this arg in the register(s) designated
1301 by the PARALLEL, but also to pass it in the stack. */
1302 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1303 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1304 args[i].pass_on_stack = 1;
1306 /* If this is an addressable type, we must preallocate the stack
1307 since we must evaluate the object into its final location.
1309 If this is to be passed in both registers and the stack, it is simpler
1310 to preallocate. */
1311 if (TREE_ADDRESSABLE (type)
1312 || (args[i].pass_on_stack && args[i].reg != 0))
1313 *must_preallocate = 1;
1315 /* Compute the stack-size of this argument. */
1316 if (args[i].reg == 0 || args[i].partial != 0
1317 || reg_parm_stack_space > 0
1318 || args[i].pass_on_stack)
1319 locate_and_pad_parm (mode, type,
1320 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1322 #else
1323 args[i].reg != 0,
1324 #endif
1325 reg_parm_stack_space,
1326 args[i].pass_on_stack ? 0 : args[i].partial,
1327 fndecl, args_size, &args[i].locate);
1328 #ifdef BLOCK_REG_PADDING
1329 else
1330 /* The argument is passed entirely in registers. See at which
1331 end it should be padded. */
1332 args[i].locate.where_pad =
1333 BLOCK_REG_PADDING (mode, type,
1334 int_size_in_bytes (type) <= UNITS_PER_WORD);
1335 #endif
1337 /* Update ARGS_SIZE, the total stack space for args so far. */
1339 args_size->constant += args[i].locate.size.constant;
1340 if (args[i].locate.size.var)
1341 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1343 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1344 have been used, etc. */
1346 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1347 type, argpos < n_named_args);
1351 /* Update ARGS_SIZE to contain the total size for the argument block.
1352 Return the original constant component of the argument block's size.
1354 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1355 for arguments passed in registers. */
1357 static int
1358 compute_argument_block_size (int reg_parm_stack_space,
1359 struct args_size *args_size,
1360 tree fndecl ATTRIBUTE_UNUSED,
1361 tree fntype ATTRIBUTE_UNUSED,
1362 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1364 int unadjusted_args_size = args_size->constant;
1366 /* For accumulate outgoing args mode we don't need to align, since the frame
1367 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1368 backends from generating misaligned frame sizes. */
1369 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1370 preferred_stack_boundary = STACK_BOUNDARY;
1372 /* Compute the actual size of the argument block required. The variable
1373 and constant sizes must be combined, the size may have to be rounded,
1374 and there may be a minimum required size. */
1376 if (args_size->var)
1378 args_size->var = ARGS_SIZE_TREE (*args_size);
1379 args_size->constant = 0;
1381 preferred_stack_boundary /= BITS_PER_UNIT;
1382 if (preferred_stack_boundary > 1)
1384 /* We don't handle this case yet. To handle it correctly we have
1385 to add the delta, round and subtract the delta.
1386 Currently no machine description requires this support. */
1387 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1388 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1391 if (reg_parm_stack_space > 0)
1393 args_size->var
1394 = size_binop (MAX_EXPR, args_size->var,
1395 ssize_int (reg_parm_stack_space));
1397 /* The area corresponding to register parameters is not to count in
1398 the size of the block we need. So make the adjustment. */
1399 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1400 args_size->var
1401 = size_binop (MINUS_EXPR, args_size->var,
1402 ssize_int (reg_parm_stack_space));
1405 else
1407 preferred_stack_boundary /= BITS_PER_UNIT;
1408 if (preferred_stack_boundary < 1)
1409 preferred_stack_boundary = 1;
1410 args_size->constant = (((args_size->constant
1411 + stack_pointer_delta
1412 + preferred_stack_boundary - 1)
1413 / preferred_stack_boundary
1414 * preferred_stack_boundary)
1415 - stack_pointer_delta);
1417 args_size->constant = MAX (args_size->constant,
1418 reg_parm_stack_space);
1420 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1421 args_size->constant -= reg_parm_stack_space;
1423 return unadjusted_args_size;
1426 /* Precompute parameters as needed for a function call.
1428 FLAGS is mask of ECF_* constants.
1430 NUM_ACTUALS is the number of arguments.
1432 ARGS is an array containing information for each argument; this
1433 routine fills in the INITIAL_VALUE and VALUE fields for each
1434 precomputed argument. */
1436 static void
1437 precompute_arguments (int num_actuals, struct arg_data *args)
1439 int i;
1441 /* If this is a libcall, then precompute all arguments so that we do not
1442 get extraneous instructions emitted as part of the libcall sequence. */
1444 /* If we preallocated the stack space, and some arguments must be passed
1445 on the stack, then we must precompute any parameter which contains a
1446 function call which will store arguments on the stack.
1447 Otherwise, evaluating the parameter may clobber previous parameters
1448 which have already been stored into the stack. (we have code to avoid
1449 such case by saving the outgoing stack arguments, but it results in
1450 worse code) */
1451 if (!ACCUMULATE_OUTGOING_ARGS)
1452 return;
1454 for (i = 0; i < num_actuals; i++)
1456 tree type;
1457 enum machine_mode mode;
1459 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1460 continue;
1462 /* If this is an addressable type, we cannot pre-evaluate it. */
1463 type = TREE_TYPE (args[i].tree_value);
1464 gcc_assert (!TREE_ADDRESSABLE (type));
1466 args[i].initial_value = args[i].value
1467 = expand_normal (args[i].tree_value);
1469 mode = TYPE_MODE (type);
1470 if (mode != args[i].mode)
1472 int unsignedp = args[i].unsignedp;
1473 args[i].value
1474 = convert_modes (args[i].mode, mode,
1475 args[i].value, args[i].unsignedp);
1477 /* CSE will replace this only if it contains args[i].value
1478 pseudo, so convert it down to the declared mode using
1479 a SUBREG. */
1480 if (REG_P (args[i].value)
1481 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1482 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1484 args[i].initial_value
1485 = gen_lowpart_SUBREG (mode, args[i].value);
1486 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1487 if (promoted_for_signed_and_unsigned_p (args[i].tree_value, mode))
1488 SUBREG_PROMOTED_SET (args[i].initial_value, SRP_SIGNED_AND_UNSIGNED);
1489 else
1490 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
1496 /* Given the current state of MUST_PREALLOCATE and information about
1497 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1498 compute and return the final value for MUST_PREALLOCATE. */
1500 static int
1501 finalize_must_preallocate (int must_preallocate, int num_actuals,
1502 struct arg_data *args, struct args_size *args_size)
1504 /* See if we have or want to preallocate stack space.
1506 If we would have to push a partially-in-regs parm
1507 before other stack parms, preallocate stack space instead.
1509 If the size of some parm is not a multiple of the required stack
1510 alignment, we must preallocate.
1512 If the total size of arguments that would otherwise create a copy in
1513 a temporary (such as a CALL) is more than half the total argument list
1514 size, preallocation is faster.
1516 Another reason to preallocate is if we have a machine (like the m88k)
1517 where stack alignment is required to be maintained between every
1518 pair of insns, not just when the call is made. However, we assume here
1519 that such machines either do not have push insns (and hence preallocation
1520 would occur anyway) or the problem is taken care of with
1521 PUSH_ROUNDING. */
1523 if (! must_preallocate)
1525 int partial_seen = 0;
1526 int copy_to_evaluate_size = 0;
1527 int i;
1529 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1531 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1532 partial_seen = 1;
1533 else if (partial_seen && args[i].reg == 0)
1534 must_preallocate = 1;
1536 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1537 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1538 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1539 || TREE_CODE (args[i].tree_value) == COND_EXPR
1540 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1541 copy_to_evaluate_size
1542 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1545 if (copy_to_evaluate_size * 2 >= args_size->constant
1546 && args_size->constant > 0)
1547 must_preallocate = 1;
1549 return must_preallocate;
1552 /* If we preallocated stack space, compute the address of each argument
1553 and store it into the ARGS array.
1555 We need not ensure it is a valid memory address here; it will be
1556 validized when it is used.
1558 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1560 static void
1561 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1563 if (argblock)
1565 rtx arg_reg = argblock;
1566 int i, arg_offset = 0;
1568 if (GET_CODE (argblock) == PLUS)
1569 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1571 for (i = 0; i < num_actuals; i++)
1573 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1574 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1575 rtx addr;
1576 unsigned int align, boundary;
1577 unsigned int units_on_stack = 0;
1578 enum machine_mode partial_mode = VOIDmode;
1580 /* Skip this parm if it will not be passed on the stack. */
1581 if (! args[i].pass_on_stack
1582 && args[i].reg != 0
1583 && args[i].partial == 0)
1584 continue;
1586 if (CONST_INT_P (offset))
1587 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
1588 else
1589 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1591 addr = plus_constant (Pmode, addr, arg_offset);
1593 if (args[i].partial != 0)
1595 /* Only part of the parameter is being passed on the stack.
1596 Generate a simple memory reference of the correct size. */
1597 units_on_stack = args[i].locate.size.constant;
1598 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1599 MODE_INT, 1);
1600 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1601 set_mem_size (args[i].stack, units_on_stack);
1603 else
1605 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1606 set_mem_attributes (args[i].stack,
1607 TREE_TYPE (args[i].tree_value), 1);
1609 align = BITS_PER_UNIT;
1610 boundary = args[i].locate.boundary;
1611 if (args[i].locate.where_pad != downward)
1612 align = boundary;
1613 else if (CONST_INT_P (offset))
1615 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1616 align = align & -align;
1618 set_mem_align (args[i].stack, align);
1620 if (CONST_INT_P (slot_offset))
1621 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
1622 else
1623 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1625 addr = plus_constant (Pmode, addr, arg_offset);
1627 if (args[i].partial != 0)
1629 /* Only part of the parameter is being passed on the stack.
1630 Generate a simple memory reference of the correct size.
1632 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1633 set_mem_size (args[i].stack_slot, units_on_stack);
1635 else
1637 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1638 set_mem_attributes (args[i].stack_slot,
1639 TREE_TYPE (args[i].tree_value), 1);
1641 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1643 /* Function incoming arguments may overlap with sibling call
1644 outgoing arguments and we cannot allow reordering of reads
1645 from function arguments with stores to outgoing arguments
1646 of sibling calls. */
1647 set_mem_alias_set (args[i].stack, 0);
1648 set_mem_alias_set (args[i].stack_slot, 0);
1653 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1654 in a call instruction.
1656 FNDECL is the tree node for the target function. For an indirect call
1657 FNDECL will be NULL_TREE.
1659 ADDR is the operand 0 of CALL_EXPR for this call. */
1661 static rtx
1662 rtx_for_function_call (tree fndecl, tree addr)
1664 rtx funexp;
1666 /* Get the function to call, in the form of RTL. */
1667 if (fndecl)
1669 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1670 TREE_USED (fndecl) = 1;
1672 /* Get a SYMBOL_REF rtx for the function address. */
1673 funexp = XEXP (DECL_RTL (fndecl), 0);
1675 else
1676 /* Generate an rtx (probably a pseudo-register) for the address. */
1678 push_temp_slots ();
1679 funexp = expand_normal (addr);
1680 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1682 return funexp;
1685 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1686 static struct
1688 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1689 or NULL_RTX if none has been scanned yet. */
1690 rtx scan_start;
1691 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1692 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1693 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1694 with fixed offset, or PC if this is with variable or unknown offset. */
1695 vec<rtx> cache;
1696 } internal_arg_pointer_exp_state;
1698 static rtx internal_arg_pointer_based_exp (rtx, bool);
1700 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1701 the tail call sequence, starting with first insn that hasn't been
1702 scanned yet, and note for each pseudo on the LHS whether it is based
1703 on crtl->args.internal_arg_pointer or not, and what offset from that
1704 that pointer it has. */
1706 static void
1707 internal_arg_pointer_based_exp_scan (void)
1709 rtx insn, scan_start = internal_arg_pointer_exp_state.scan_start;
1711 if (scan_start == NULL_RTX)
1712 insn = get_insns ();
1713 else
1714 insn = NEXT_INSN (scan_start);
1716 while (insn)
1718 rtx set = single_set (insn);
1719 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1721 rtx val = NULL_RTX;
1722 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1723 /* Punt on pseudos set multiple times. */
1724 if (idx < internal_arg_pointer_exp_state.cache.length ()
1725 && (internal_arg_pointer_exp_state.cache[idx]
1726 != NULL_RTX))
1727 val = pc_rtx;
1728 else
1729 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1730 if (val != NULL_RTX)
1732 if (idx >= internal_arg_pointer_exp_state.cache.length ())
1733 internal_arg_pointer_exp_state.cache
1734 .safe_grow_cleared (idx + 1);
1735 internal_arg_pointer_exp_state.cache[idx] = val;
1738 if (NEXT_INSN (insn) == NULL_RTX)
1739 scan_start = insn;
1740 insn = NEXT_INSN (insn);
1743 internal_arg_pointer_exp_state.scan_start = scan_start;
1746 /* Helper function for internal_arg_pointer_based_exp, called through
1747 for_each_rtx. Return 1 if *LOC is a register based on
1748 crtl->args.internal_arg_pointer. Return -1 if *LOC is not based on it
1749 and the subexpressions need not be examined. Otherwise return 0. */
1751 static int
1752 internal_arg_pointer_based_exp_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
1754 if (REG_P (*loc) && internal_arg_pointer_based_exp (*loc, false) != NULL_RTX)
1755 return 1;
1756 if (MEM_P (*loc))
1757 return -1;
1758 return 0;
1761 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1762 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1763 it with fixed offset, or PC if this is with variable or unknown offset.
1764 TOPLEVEL is true if the function is invoked at the topmost level. */
1766 static rtx
1767 internal_arg_pointer_based_exp (rtx rtl, bool toplevel)
1769 if (CONSTANT_P (rtl))
1770 return NULL_RTX;
1772 if (rtl == crtl->args.internal_arg_pointer)
1773 return const0_rtx;
1775 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1776 return NULL_RTX;
1778 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1780 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1781 if (val == NULL_RTX || val == pc_rtx)
1782 return val;
1783 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
1786 /* When called at the topmost level, scan pseudo assignments in between the
1787 last scanned instruction in the tail call sequence and the latest insn
1788 in that sequence. */
1789 if (toplevel)
1790 internal_arg_pointer_based_exp_scan ();
1792 if (REG_P (rtl))
1794 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1795 if (idx < internal_arg_pointer_exp_state.cache.length ())
1796 return internal_arg_pointer_exp_state.cache[idx];
1798 return NULL_RTX;
1801 if (for_each_rtx (&rtl, internal_arg_pointer_based_exp_1, NULL))
1802 return pc_rtx;
1804 return NULL_RTX;
1807 /* Return true if and only if SIZE storage units (usually bytes)
1808 starting from address ADDR overlap with already clobbered argument
1809 area. This function is used to determine if we should give up a
1810 sibcall. */
1812 static bool
1813 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1815 HOST_WIDE_INT i;
1816 rtx val;
1818 if (bitmap_empty_p (stored_args_map))
1819 return false;
1820 val = internal_arg_pointer_based_exp (addr, true);
1821 if (val == NULL_RTX)
1822 return false;
1823 else if (val == pc_rtx)
1824 return true;
1825 else
1826 i = INTVAL (val);
1827 #ifdef STACK_GROWS_DOWNWARD
1828 i -= crtl->args.pretend_args_size;
1829 #else
1830 i += crtl->args.pretend_args_size;
1831 #endif
1833 #ifdef ARGS_GROW_DOWNWARD
1834 i = -i - size;
1835 #endif
1836 if (size > 0)
1838 unsigned HOST_WIDE_INT k;
1840 for (k = 0; k < size; k++)
1841 if (i + k < SBITMAP_SIZE (stored_args_map)
1842 && bitmap_bit_p (stored_args_map, i + k))
1843 return true;
1846 return false;
1849 /* Do the register loads required for any wholly-register parms or any
1850 parms which are passed both on the stack and in a register. Their
1851 expressions were already evaluated.
1853 Mark all register-parms as living through the call, putting these USE
1854 insns in the CALL_INSN_FUNCTION_USAGE field.
1856 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1857 checking, setting *SIBCALL_FAILURE if appropriate. */
1859 static void
1860 load_register_parameters (struct arg_data *args, int num_actuals,
1861 rtx *call_fusage, int flags, int is_sibcall,
1862 int *sibcall_failure)
1864 int i, j;
1866 for (i = 0; i < num_actuals; i++)
1868 rtx reg = ((flags & ECF_SIBCALL)
1869 ? args[i].tail_call_reg : args[i].reg);
1870 if (reg)
1872 int partial = args[i].partial;
1873 int nregs;
1874 int size = 0;
1875 rtx before_arg = get_last_insn ();
1876 /* Set non-negative if we must move a word at a time, even if
1877 just one word (e.g, partial == 4 && mode == DFmode). Set
1878 to -1 if we just use a normal move insn. This value can be
1879 zero if the argument is a zero size structure. */
1880 nregs = -1;
1881 if (GET_CODE (reg) == PARALLEL)
1883 else if (partial)
1885 gcc_assert (partial % UNITS_PER_WORD == 0);
1886 nregs = partial / UNITS_PER_WORD;
1888 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1890 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1891 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1893 else
1894 size = GET_MODE_SIZE (args[i].mode);
1896 /* Handle calls that pass values in multiple non-contiguous
1897 locations. The Irix 6 ABI has examples of this. */
1899 if (GET_CODE (reg) == PARALLEL)
1900 emit_group_move (reg, args[i].parallel_value);
1902 /* If simple case, just do move. If normal partial, store_one_arg
1903 has already loaded the register for us. In all other cases,
1904 load the register(s) from memory. */
1906 else if (nregs == -1)
1908 emit_move_insn (reg, args[i].value);
1909 #ifdef BLOCK_REG_PADDING
1910 /* Handle case where we have a value that needs shifting
1911 up to the msb. eg. a QImode value and we're padding
1912 upward on a BYTES_BIG_ENDIAN machine. */
1913 if (size < UNITS_PER_WORD
1914 && (args[i].locate.where_pad
1915 == (BYTES_BIG_ENDIAN ? upward : downward)))
1917 rtx x;
1918 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1920 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1921 report the whole reg as used. Strictly speaking, the
1922 call only uses SIZE bytes at the msb end, but it doesn't
1923 seem worth generating rtl to say that. */
1924 reg = gen_rtx_REG (word_mode, REGNO (reg));
1925 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
1926 if (x != reg)
1927 emit_move_insn (reg, x);
1929 #endif
1932 /* If we have pre-computed the values to put in the registers in
1933 the case of non-aligned structures, copy them in now. */
1935 else if (args[i].n_aligned_regs != 0)
1936 for (j = 0; j < args[i].n_aligned_regs; j++)
1937 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1938 args[i].aligned_regs[j]);
1940 else if (partial == 0 || args[i].pass_on_stack)
1942 rtx mem = validize_mem (copy_rtx (args[i].value));
1944 /* Check for overlap with already clobbered argument area,
1945 providing that this has non-zero size. */
1946 if (is_sibcall
1947 && (size == 0
1948 || mem_overlaps_already_clobbered_arg_p
1949 (XEXP (args[i].value, 0), size)))
1950 *sibcall_failure = 1;
1952 /* Handle a BLKmode that needs shifting. */
1953 if (nregs == 1 && size < UNITS_PER_WORD
1954 #ifdef BLOCK_REG_PADDING
1955 && args[i].locate.where_pad == downward
1956 #else
1957 && BYTES_BIG_ENDIAN
1958 #endif
1961 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1962 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1963 rtx x = gen_reg_rtx (word_mode);
1964 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1965 enum tree_code dir = BYTES_BIG_ENDIAN ? RSHIFT_EXPR
1966 : LSHIFT_EXPR;
1968 emit_move_insn (x, tem);
1969 x = expand_shift (dir, word_mode, x, shift, ri, 1);
1970 if (x != ri)
1971 emit_move_insn (ri, x);
1973 else
1974 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1977 /* When a parameter is a block, and perhaps in other cases, it is
1978 possible that it did a load from an argument slot that was
1979 already clobbered. */
1980 if (is_sibcall
1981 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1982 *sibcall_failure = 1;
1984 /* Handle calls that pass values in multiple non-contiguous
1985 locations. The Irix 6 ABI has examples of this. */
1986 if (GET_CODE (reg) == PARALLEL)
1987 use_group_regs (call_fusage, reg);
1988 else if (nregs == -1)
1989 use_reg_mode (call_fusage, reg,
1990 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
1991 else if (nregs > 0)
1992 use_regs (call_fusage, REGNO (reg), nregs);
1997 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1998 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1999 bytes, then we would need to push some additional bytes to pad the
2000 arguments. So, we compute an adjust to the stack pointer for an
2001 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2002 bytes. Then, when the arguments are pushed the stack will be perfectly
2003 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2004 be popped after the call. Returns the adjustment. */
2006 static int
2007 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2008 struct args_size *args_size,
2009 unsigned int preferred_unit_stack_boundary)
2011 /* The number of bytes to pop so that the stack will be
2012 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2013 HOST_WIDE_INT adjustment;
2014 /* The alignment of the stack after the arguments are pushed, if we
2015 just pushed the arguments without adjust the stack here. */
2016 unsigned HOST_WIDE_INT unadjusted_alignment;
2018 unadjusted_alignment
2019 = ((stack_pointer_delta + unadjusted_args_size)
2020 % preferred_unit_stack_boundary);
2022 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2023 as possible -- leaving just enough left to cancel out the
2024 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2025 PENDING_STACK_ADJUST is non-negative, and congruent to
2026 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2028 /* Begin by trying to pop all the bytes. */
2029 unadjusted_alignment
2030 = (unadjusted_alignment
2031 - (pending_stack_adjust % preferred_unit_stack_boundary));
2032 adjustment = pending_stack_adjust;
2033 /* Push enough additional bytes that the stack will be aligned
2034 after the arguments are pushed. */
2035 if (preferred_unit_stack_boundary > 1)
2037 if (unadjusted_alignment > 0)
2038 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2039 else
2040 adjustment += unadjusted_alignment;
2043 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2044 bytes after the call. The right number is the entire
2045 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2046 by the arguments in the first place. */
2047 args_size->constant
2048 = pending_stack_adjust - adjustment + unadjusted_args_size;
2050 return adjustment;
2053 /* Scan X expression if it does not dereference any argument slots
2054 we already clobbered by tail call arguments (as noted in stored_args_map
2055 bitmap).
2056 Return nonzero if X expression dereferences such argument slots,
2057 zero otherwise. */
2059 static int
2060 check_sibcall_argument_overlap_1 (rtx x)
2062 RTX_CODE code;
2063 int i, j;
2064 const char *fmt;
2066 if (x == NULL_RTX)
2067 return 0;
2069 code = GET_CODE (x);
2071 /* We need not check the operands of the CALL expression itself. */
2072 if (code == CALL)
2073 return 0;
2075 if (code == MEM)
2076 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2077 GET_MODE_SIZE (GET_MODE (x)));
2079 /* Scan all subexpressions. */
2080 fmt = GET_RTX_FORMAT (code);
2081 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2083 if (*fmt == 'e')
2085 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2086 return 1;
2088 else if (*fmt == 'E')
2090 for (j = 0; j < XVECLEN (x, i); j++)
2091 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2092 return 1;
2095 return 0;
2098 /* Scan sequence after INSN if it does not dereference any argument slots
2099 we already clobbered by tail call arguments (as noted in stored_args_map
2100 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2101 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2102 should be 0). Return nonzero if sequence after INSN dereferences such argument
2103 slots, zero otherwise. */
2105 static int
2106 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
2108 int low, high;
2110 if (insn == NULL_RTX)
2111 insn = get_insns ();
2112 else
2113 insn = NEXT_INSN (insn);
2115 for (; insn; insn = NEXT_INSN (insn))
2116 if (INSN_P (insn)
2117 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2118 break;
2120 if (mark_stored_args_map)
2122 #ifdef ARGS_GROW_DOWNWARD
2123 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2124 #else
2125 low = arg->locate.slot_offset.constant;
2126 #endif
2128 for (high = low + arg->locate.size.constant; low < high; low++)
2129 bitmap_set_bit (stored_args_map, low);
2131 return insn != NULL_RTX;
2134 /* Given that a function returns a value of mode MODE at the most
2135 significant end of hard register VALUE, shift VALUE left or right
2136 as specified by LEFT_P. Return true if some action was needed. */
2138 bool
2139 shift_return_value (enum machine_mode mode, bool left_p, rtx value)
2141 HOST_WIDE_INT shift;
2143 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2144 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2145 if (shift == 0)
2146 return false;
2148 /* Use ashr rather than lshr for right shifts. This is for the benefit
2149 of the MIPS port, which requires SImode values to be sign-extended
2150 when stored in 64-bit registers. */
2151 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2152 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2153 gcc_unreachable ();
2154 return true;
2157 /* If X is a likely-spilled register value, copy it to a pseudo
2158 register and return that register. Return X otherwise. */
2160 static rtx
2161 avoid_likely_spilled_reg (rtx x)
2163 rtx new_rtx;
2165 if (REG_P (x)
2166 && HARD_REGISTER_P (x)
2167 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2169 /* Make sure that we generate a REG rather than a CONCAT.
2170 Moves into CONCATs can need nontrivial instructions,
2171 and the whole point of this function is to avoid
2172 using the hard register directly in such a situation. */
2173 generating_concat_p = 0;
2174 new_rtx = gen_reg_rtx (GET_MODE (x));
2175 generating_concat_p = 1;
2176 emit_move_insn (new_rtx, x);
2177 return new_rtx;
2179 return x;
2182 /* Generate all the code for a CALL_EXPR exp
2183 and return an rtx for its value.
2184 Store the value in TARGET (specified as an rtx) if convenient.
2185 If the value is stored in TARGET then TARGET is returned.
2186 If IGNORE is nonzero, then we ignore the value of the function call. */
2189 expand_call (tree exp, rtx target, int ignore)
2191 /* Nonzero if we are currently expanding a call. */
2192 static int currently_expanding_call = 0;
2194 /* RTX for the function to be called. */
2195 rtx funexp;
2196 /* Sequence of insns to perform a normal "call". */
2197 rtx normal_call_insns = NULL_RTX;
2198 /* Sequence of insns to perform a tail "call". */
2199 rtx tail_call_insns = NULL_RTX;
2200 /* Data type of the function. */
2201 tree funtype;
2202 tree type_arg_types;
2203 tree rettype;
2204 /* Declaration of the function being called,
2205 or 0 if the function is computed (not known by name). */
2206 tree fndecl = 0;
2207 /* The type of the function being called. */
2208 tree fntype;
2209 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2210 int pass;
2212 /* Register in which non-BLKmode value will be returned,
2213 or 0 if no value or if value is BLKmode. */
2214 rtx valreg;
2215 /* Address where we should return a BLKmode value;
2216 0 if value not BLKmode. */
2217 rtx structure_value_addr = 0;
2218 /* Nonzero if that address is being passed by treating it as
2219 an extra, implicit first parameter. Otherwise,
2220 it is passed by being copied directly into struct_value_rtx. */
2221 int structure_value_addr_parm = 0;
2222 /* Holds the value of implicit argument for the struct value. */
2223 tree structure_value_addr_value = NULL_TREE;
2224 /* Size of aggregate value wanted, or zero if none wanted
2225 or if we are using the non-reentrant PCC calling convention
2226 or expecting the value in registers. */
2227 HOST_WIDE_INT struct_value_size = 0;
2228 /* Nonzero if called function returns an aggregate in memory PCC style,
2229 by returning the address of where to find it. */
2230 int pcc_struct_value = 0;
2231 rtx struct_value = 0;
2233 /* Number of actual parameters in this call, including struct value addr. */
2234 int num_actuals;
2235 /* Number of named args. Args after this are anonymous ones
2236 and they must all go on the stack. */
2237 int n_named_args;
2238 /* Number of complex actual arguments that need to be split. */
2239 int num_complex_actuals = 0;
2241 /* Vector of information about each argument.
2242 Arguments are numbered in the order they will be pushed,
2243 not the order they are written. */
2244 struct arg_data *args;
2246 /* Total size in bytes of all the stack-parms scanned so far. */
2247 struct args_size args_size;
2248 struct args_size adjusted_args_size;
2249 /* Size of arguments before any adjustments (such as rounding). */
2250 int unadjusted_args_size;
2251 /* Data on reg parms scanned so far. */
2252 CUMULATIVE_ARGS args_so_far_v;
2253 cumulative_args_t args_so_far;
2254 /* Nonzero if a reg parm has been scanned. */
2255 int reg_parm_seen;
2256 /* Nonzero if this is an indirect function call. */
2258 /* Nonzero if we must avoid push-insns in the args for this call.
2259 If stack space is allocated for register parameters, but not by the
2260 caller, then it is preallocated in the fixed part of the stack frame.
2261 So the entire argument block must then be preallocated (i.e., we
2262 ignore PUSH_ROUNDING in that case). */
2264 int must_preallocate = !PUSH_ARGS;
2266 /* Size of the stack reserved for parameter registers. */
2267 int reg_parm_stack_space = 0;
2269 /* Address of space preallocated for stack parms
2270 (on machines that lack push insns), or 0 if space not preallocated. */
2271 rtx argblock = 0;
2273 /* Mask of ECF_ and ERF_ flags. */
2274 int flags = 0;
2275 int return_flags = 0;
2276 #ifdef REG_PARM_STACK_SPACE
2277 /* Define the boundary of the register parm stack space that needs to be
2278 saved, if any. */
2279 int low_to_save, high_to_save;
2280 rtx save_area = 0; /* Place that it is saved */
2281 #endif
2283 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2284 char *initial_stack_usage_map = stack_usage_map;
2285 char *stack_usage_map_buf = NULL;
2287 int old_stack_allocated;
2289 /* State variables to track stack modifications. */
2290 rtx old_stack_level = 0;
2291 int old_stack_arg_under_construction = 0;
2292 int old_pending_adj = 0;
2293 int old_inhibit_defer_pop = inhibit_defer_pop;
2295 /* Some stack pointer alterations we make are performed via
2296 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2297 which we then also need to save/restore along the way. */
2298 int old_stack_pointer_delta = 0;
2300 rtx call_fusage;
2301 tree addr = CALL_EXPR_FN (exp);
2302 int i;
2303 /* The alignment of the stack, in bits. */
2304 unsigned HOST_WIDE_INT preferred_stack_boundary;
2305 /* The alignment of the stack, in bytes. */
2306 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2307 /* The static chain value to use for this call. */
2308 rtx static_chain_value;
2309 /* See if this is "nothrow" function call. */
2310 if (TREE_NOTHROW (exp))
2311 flags |= ECF_NOTHROW;
2313 /* See if we can find a DECL-node for the actual function, and get the
2314 function attributes (flags) from the function decl or type node. */
2315 fndecl = get_callee_fndecl (exp);
2316 if (fndecl)
2318 fntype = TREE_TYPE (fndecl);
2319 flags |= flags_from_decl_or_type (fndecl);
2320 return_flags |= decl_return_flags (fndecl);
2322 else
2324 fntype = TREE_TYPE (TREE_TYPE (addr));
2325 flags |= flags_from_decl_or_type (fntype);
2327 rettype = TREE_TYPE (exp);
2329 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2331 /* Warn if this value is an aggregate type,
2332 regardless of which calling convention we are using for it. */
2333 if (AGGREGATE_TYPE_P (rettype))
2334 warning (OPT_Waggregate_return, "function call has aggregate value");
2336 /* If the result of a non looping pure or const function call is
2337 ignored (or void), and none of its arguments are volatile, we can
2338 avoid expanding the call and just evaluate the arguments for
2339 side-effects. */
2340 if ((flags & (ECF_CONST | ECF_PURE))
2341 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2342 && (ignore || target == const0_rtx
2343 || TYPE_MODE (rettype) == VOIDmode))
2345 bool volatilep = false;
2346 tree arg;
2347 call_expr_arg_iterator iter;
2349 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2350 if (TREE_THIS_VOLATILE (arg))
2352 volatilep = true;
2353 break;
2356 if (! volatilep)
2358 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2359 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2360 return const0_rtx;
2364 #ifdef REG_PARM_STACK_SPACE
2365 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2366 #endif
2368 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2369 && reg_parm_stack_space > 0 && PUSH_ARGS)
2370 must_preallocate = 1;
2372 /* Set up a place to return a structure. */
2374 /* Cater to broken compilers. */
2375 if (aggregate_value_p (exp, fntype))
2377 /* This call returns a big structure. */
2378 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2380 #ifdef PCC_STATIC_STRUCT_RETURN
2382 pcc_struct_value = 1;
2384 #else /* not PCC_STATIC_STRUCT_RETURN */
2386 struct_value_size = int_size_in_bytes (rettype);
2388 if (target && MEM_P (target) && CALL_EXPR_RETURN_SLOT_OPT (exp))
2389 structure_value_addr = XEXP (target, 0);
2390 else
2392 /* For variable-sized objects, we must be called with a target
2393 specified. If we were to allocate space on the stack here,
2394 we would have no way of knowing when to free it. */
2395 rtx d = assign_temp (rettype, 1, 1);
2396 structure_value_addr = XEXP (d, 0);
2397 target = 0;
2400 #endif /* not PCC_STATIC_STRUCT_RETURN */
2403 /* Figure out the amount to which the stack should be aligned. */
2404 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2405 if (fndecl)
2407 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2408 /* Without automatic stack alignment, we can't increase preferred
2409 stack boundary. With automatic stack alignment, it is
2410 unnecessary since unless we can guarantee that all callers will
2411 align the outgoing stack properly, callee has to align its
2412 stack anyway. */
2413 if (i
2414 && i->preferred_incoming_stack_boundary
2415 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2416 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2419 /* Operand 0 is a pointer-to-function; get the type of the function. */
2420 funtype = TREE_TYPE (addr);
2421 gcc_assert (POINTER_TYPE_P (funtype));
2422 funtype = TREE_TYPE (funtype);
2424 /* Count whether there are actual complex arguments that need to be split
2425 into their real and imaginary parts. Munge the type_arg_types
2426 appropriately here as well. */
2427 if (targetm.calls.split_complex_arg)
2429 call_expr_arg_iterator iter;
2430 tree arg;
2431 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2433 tree type = TREE_TYPE (arg);
2434 if (type && TREE_CODE (type) == COMPLEX_TYPE
2435 && targetm.calls.split_complex_arg (type))
2436 num_complex_actuals++;
2438 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2440 else
2441 type_arg_types = TYPE_ARG_TYPES (funtype);
2443 if (flags & ECF_MAY_BE_ALLOCA)
2444 cfun->calls_alloca = 1;
2446 /* If struct_value_rtx is 0, it means pass the address
2447 as if it were an extra parameter. Put the argument expression
2448 in structure_value_addr_value. */
2449 if (structure_value_addr && struct_value == 0)
2451 /* If structure_value_addr is a REG other than
2452 virtual_outgoing_args_rtx, we can use always use it. If it
2453 is not a REG, we must always copy it into a register.
2454 If it is virtual_outgoing_args_rtx, we must copy it to another
2455 register in some cases. */
2456 rtx temp = (!REG_P (structure_value_addr)
2457 || (ACCUMULATE_OUTGOING_ARGS
2458 && stack_arg_under_construction
2459 && structure_value_addr == virtual_outgoing_args_rtx)
2460 ? copy_addr_to_reg (convert_memory_address
2461 (Pmode, structure_value_addr))
2462 : structure_value_addr);
2464 structure_value_addr_value =
2465 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2466 structure_value_addr_parm = 1;
2469 /* Count the arguments and set NUM_ACTUALS. */
2470 num_actuals =
2471 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2473 /* Compute number of named args.
2474 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2476 if (type_arg_types != 0)
2477 n_named_args
2478 = (list_length (type_arg_types)
2479 /* Count the struct value address, if it is passed as a parm. */
2480 + structure_value_addr_parm);
2481 else
2482 /* If we know nothing, treat all args as named. */
2483 n_named_args = num_actuals;
2485 /* Start updating where the next arg would go.
2487 On some machines (such as the PA) indirect calls have a different
2488 calling convention than normal calls. The fourth argument in
2489 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2490 or not. */
2491 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2492 args_so_far = pack_cumulative_args (&args_so_far_v);
2494 /* Now possibly adjust the number of named args.
2495 Normally, don't include the last named arg if anonymous args follow.
2496 We do include the last named arg if
2497 targetm.calls.strict_argument_naming() returns nonzero.
2498 (If no anonymous args follow, the result of list_length is actually
2499 one too large. This is harmless.)
2501 If targetm.calls.pretend_outgoing_varargs_named() returns
2502 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2503 this machine will be able to place unnamed args that were passed
2504 in registers into the stack. So treat all args as named. This
2505 allows the insns emitting for a specific argument list to be
2506 independent of the function declaration.
2508 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2509 we do not have any reliable way to pass unnamed args in
2510 registers, so we must force them into memory. */
2512 if (type_arg_types != 0
2513 && targetm.calls.strict_argument_naming (args_so_far))
2515 else if (type_arg_types != 0
2516 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2517 /* Don't include the last named arg. */
2518 --n_named_args;
2519 else
2520 /* Treat all args as named. */
2521 n_named_args = num_actuals;
2523 /* Make a vector to hold all the information about each arg. */
2524 args = XALLOCAVEC (struct arg_data, num_actuals);
2525 memset (args, 0, num_actuals * sizeof (struct arg_data));
2527 /* Build up entries in the ARGS array, compute the size of the
2528 arguments into ARGS_SIZE, etc. */
2529 initialize_argument_information (num_actuals, args, &args_size,
2530 n_named_args, exp,
2531 structure_value_addr_value, fndecl, fntype,
2532 args_so_far, reg_parm_stack_space,
2533 &old_stack_level, &old_pending_adj,
2534 &must_preallocate, &flags,
2535 &try_tail_call, CALL_FROM_THUNK_P (exp));
2537 if (args_size.var)
2538 must_preallocate = 1;
2540 /* Now make final decision about preallocating stack space. */
2541 must_preallocate = finalize_must_preallocate (must_preallocate,
2542 num_actuals, args,
2543 &args_size);
2545 /* If the structure value address will reference the stack pointer, we
2546 must stabilize it. We don't need to do this if we know that we are
2547 not going to adjust the stack pointer in processing this call. */
2549 if (structure_value_addr
2550 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2551 || reg_mentioned_p (virtual_outgoing_args_rtx,
2552 structure_value_addr))
2553 && (args_size.var
2554 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2555 structure_value_addr = copy_to_reg (structure_value_addr);
2557 /* Tail calls can make things harder to debug, and we've traditionally
2558 pushed these optimizations into -O2. Don't try if we're already
2559 expanding a call, as that means we're an argument. Don't try if
2560 there's cleanups, as we know there's code to follow the call. */
2562 if (currently_expanding_call++ != 0
2563 || !flag_optimize_sibling_calls
2564 || args_size.var
2565 || dbg_cnt (tail_call) == false)
2566 try_tail_call = 0;
2568 /* Rest of purposes for tail call optimizations to fail. */
2569 if (
2570 #ifdef HAVE_sibcall_epilogue
2571 !HAVE_sibcall_epilogue
2572 #else
2574 #endif
2575 || !try_tail_call
2576 /* Doing sibling call optimization needs some work, since
2577 structure_value_addr can be allocated on the stack.
2578 It does not seem worth the effort since few optimizable
2579 sibling calls will return a structure. */
2580 || structure_value_addr != NULL_RTX
2581 #ifdef REG_PARM_STACK_SPACE
2582 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2583 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2584 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2585 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl))
2586 #endif
2587 /* Check whether the target is able to optimize the call
2588 into a sibcall. */
2589 || !targetm.function_ok_for_sibcall (fndecl, exp)
2590 /* Functions that do not return exactly once may not be sibcall
2591 optimized. */
2592 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2593 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2594 /* If the called function is nested in the current one, it might access
2595 some of the caller's arguments, but could clobber them beforehand if
2596 the argument areas are shared. */
2597 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2598 /* If this function requires more stack slots than the current
2599 function, we cannot change it into a sibling call.
2600 crtl->args.pretend_args_size is not part of the
2601 stack allocated by our caller. */
2602 || args_size.constant > (crtl->args.size
2603 - crtl->args.pretend_args_size)
2604 /* If the callee pops its own arguments, then it must pop exactly
2605 the same number of arguments as the current function. */
2606 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2607 != targetm.calls.return_pops_args (current_function_decl,
2608 TREE_TYPE (current_function_decl),
2609 crtl->args.size))
2610 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2611 try_tail_call = 0;
2613 /* Check if caller and callee disagree in promotion of function
2614 return value. */
2615 if (try_tail_call)
2617 enum machine_mode caller_mode, caller_promoted_mode;
2618 enum machine_mode callee_mode, callee_promoted_mode;
2619 int caller_unsignedp, callee_unsignedp;
2620 tree caller_res = DECL_RESULT (current_function_decl);
2622 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2623 caller_mode = DECL_MODE (caller_res);
2624 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2625 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2626 caller_promoted_mode
2627 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2628 &caller_unsignedp,
2629 TREE_TYPE (current_function_decl), 1);
2630 callee_promoted_mode
2631 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2632 &callee_unsignedp,
2633 funtype, 1);
2634 if (caller_mode != VOIDmode
2635 && (caller_promoted_mode != callee_promoted_mode
2636 || ((caller_mode != caller_promoted_mode
2637 || callee_mode != callee_promoted_mode)
2638 && (caller_unsignedp != callee_unsignedp
2639 || GET_MODE_BITSIZE (caller_mode)
2640 < GET_MODE_BITSIZE (callee_mode)))))
2641 try_tail_call = 0;
2644 /* Ensure current function's preferred stack boundary is at least
2645 what we need. Stack alignment may also increase preferred stack
2646 boundary. */
2647 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2648 crtl->preferred_stack_boundary = preferred_stack_boundary;
2649 else
2650 preferred_stack_boundary = crtl->preferred_stack_boundary;
2652 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2654 /* We want to make two insn chains; one for a sibling call, the other
2655 for a normal call. We will select one of the two chains after
2656 initial RTL generation is complete. */
2657 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2659 int sibcall_failure = 0;
2660 /* We want to emit any pending stack adjustments before the tail
2661 recursion "call". That way we know any adjustment after the tail
2662 recursion call can be ignored if we indeed use the tail
2663 call expansion. */
2664 saved_pending_stack_adjust save;
2665 rtx insns;
2666 rtx before_call, next_arg_reg, after_args;
2668 if (pass == 0)
2670 /* State variables we need to save and restore between
2671 iterations. */
2672 save_pending_stack_adjust (&save);
2674 if (pass)
2675 flags &= ~ECF_SIBCALL;
2676 else
2677 flags |= ECF_SIBCALL;
2679 /* Other state variables that we must reinitialize each time
2680 through the loop (that are not initialized by the loop itself). */
2681 argblock = 0;
2682 call_fusage = 0;
2684 /* Start a new sequence for the normal call case.
2686 From this point on, if the sibling call fails, we want to set
2687 sibcall_failure instead of continuing the loop. */
2688 start_sequence ();
2690 /* Don't let pending stack adjusts add up to too much.
2691 Also, do all pending adjustments now if there is any chance
2692 this might be a call to alloca or if we are expanding a sibling
2693 call sequence.
2694 Also do the adjustments before a throwing call, otherwise
2695 exception handling can fail; PR 19225. */
2696 if (pending_stack_adjust >= 32
2697 || (pending_stack_adjust > 0
2698 && (flags & ECF_MAY_BE_ALLOCA))
2699 || (pending_stack_adjust > 0
2700 && flag_exceptions && !(flags & ECF_NOTHROW))
2701 || pass == 0)
2702 do_pending_stack_adjust ();
2704 /* Precompute any arguments as needed. */
2705 if (pass)
2706 precompute_arguments (num_actuals, args);
2708 /* Now we are about to start emitting insns that can be deleted
2709 if a libcall is deleted. */
2710 if (pass && (flags & ECF_MALLOC))
2711 start_sequence ();
2713 if (pass == 0 && crtl->stack_protect_guard)
2714 stack_protect_epilogue ();
2716 adjusted_args_size = args_size;
2717 /* Compute the actual size of the argument block required. The variable
2718 and constant sizes must be combined, the size may have to be rounded,
2719 and there may be a minimum required size. When generating a sibcall
2720 pattern, do not round up, since we'll be re-using whatever space our
2721 caller provided. */
2722 unadjusted_args_size
2723 = compute_argument_block_size (reg_parm_stack_space,
2724 &adjusted_args_size,
2725 fndecl, fntype,
2726 (pass == 0 ? 0
2727 : preferred_stack_boundary));
2729 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2731 /* The argument block when performing a sibling call is the
2732 incoming argument block. */
2733 if (pass == 0)
2735 argblock = crtl->args.internal_arg_pointer;
2736 argblock
2737 #ifdef STACK_GROWS_DOWNWARD
2738 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
2739 #else
2740 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
2741 #endif
2742 stored_args_map = sbitmap_alloc (args_size.constant);
2743 bitmap_clear (stored_args_map);
2746 /* If we have no actual push instructions, or shouldn't use them,
2747 make space for all args right now. */
2748 else if (adjusted_args_size.var != 0)
2750 if (old_stack_level == 0)
2752 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2753 old_stack_pointer_delta = stack_pointer_delta;
2754 old_pending_adj = pending_stack_adjust;
2755 pending_stack_adjust = 0;
2756 /* stack_arg_under_construction says whether a stack arg is
2757 being constructed at the old stack level. Pushing the stack
2758 gets a clean outgoing argument block. */
2759 old_stack_arg_under_construction = stack_arg_under_construction;
2760 stack_arg_under_construction = 0;
2762 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2763 if (flag_stack_usage_info)
2764 current_function_has_unbounded_dynamic_stack_size = 1;
2766 else
2768 /* Note that we must go through the motions of allocating an argument
2769 block even if the size is zero because we may be storing args
2770 in the area reserved for register arguments, which may be part of
2771 the stack frame. */
2773 int needed = adjusted_args_size.constant;
2775 /* Store the maximum argument space used. It will be pushed by
2776 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2777 checking). */
2779 if (needed > crtl->outgoing_args_size)
2780 crtl->outgoing_args_size = needed;
2782 if (must_preallocate)
2784 if (ACCUMULATE_OUTGOING_ARGS)
2786 /* Since the stack pointer will never be pushed, it is
2787 possible for the evaluation of a parm to clobber
2788 something we have already written to the stack.
2789 Since most function calls on RISC machines do not use
2790 the stack, this is uncommon, but must work correctly.
2792 Therefore, we save any area of the stack that was already
2793 written and that we are using. Here we set up to do this
2794 by making a new stack usage map from the old one. The
2795 actual save will be done by store_one_arg.
2797 Another approach might be to try to reorder the argument
2798 evaluations to avoid this conflicting stack usage. */
2800 /* Since we will be writing into the entire argument area,
2801 the map must be allocated for its entire size, not just
2802 the part that is the responsibility of the caller. */
2803 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2804 needed += reg_parm_stack_space;
2806 #ifdef ARGS_GROW_DOWNWARD
2807 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2808 needed + 1);
2809 #else
2810 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2811 needed);
2812 #endif
2813 free (stack_usage_map_buf);
2814 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2815 stack_usage_map = stack_usage_map_buf;
2817 if (initial_highest_arg_in_use)
2818 memcpy (stack_usage_map, initial_stack_usage_map,
2819 initial_highest_arg_in_use);
2821 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2822 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2823 (highest_outgoing_arg_in_use
2824 - initial_highest_arg_in_use));
2825 needed = 0;
2827 /* The address of the outgoing argument list must not be
2828 copied to a register here, because argblock would be left
2829 pointing to the wrong place after the call to
2830 allocate_dynamic_stack_space below. */
2832 argblock = virtual_outgoing_args_rtx;
2834 else
2836 if (inhibit_defer_pop == 0)
2838 /* Try to reuse some or all of the pending_stack_adjust
2839 to get this space. */
2840 needed
2841 = (combine_pending_stack_adjustment_and_call
2842 (unadjusted_args_size,
2843 &adjusted_args_size,
2844 preferred_unit_stack_boundary));
2846 /* combine_pending_stack_adjustment_and_call computes
2847 an adjustment before the arguments are allocated.
2848 Account for them and see whether or not the stack
2849 needs to go up or down. */
2850 needed = unadjusted_args_size - needed;
2852 if (needed < 0)
2854 /* We're releasing stack space. */
2855 /* ??? We can avoid any adjustment at all if we're
2856 already aligned. FIXME. */
2857 pending_stack_adjust = -needed;
2858 do_pending_stack_adjust ();
2859 needed = 0;
2861 else
2862 /* We need to allocate space. We'll do that in
2863 push_block below. */
2864 pending_stack_adjust = 0;
2867 /* Special case this because overhead of `push_block' in
2868 this case is non-trivial. */
2869 if (needed == 0)
2870 argblock = virtual_outgoing_args_rtx;
2871 else
2873 argblock = push_block (GEN_INT (needed), 0, 0);
2874 #ifdef ARGS_GROW_DOWNWARD
2875 argblock = plus_constant (Pmode, argblock, needed);
2876 #endif
2879 /* We only really need to call `copy_to_reg' in the case
2880 where push insns are going to be used to pass ARGBLOCK
2881 to a function call in ARGS. In that case, the stack
2882 pointer changes value from the allocation point to the
2883 call point, and hence the value of
2884 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2885 as well always do it. */
2886 argblock = copy_to_reg (argblock);
2891 if (ACCUMULATE_OUTGOING_ARGS)
2893 /* The save/restore code in store_one_arg handles all
2894 cases except one: a constructor call (including a C
2895 function returning a BLKmode struct) to initialize
2896 an argument. */
2897 if (stack_arg_under_construction)
2899 rtx push_size
2900 = GEN_INT (adjusted_args_size.constant
2901 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
2902 : TREE_TYPE (fndecl))) ? 0
2903 : reg_parm_stack_space));
2904 if (old_stack_level == 0)
2906 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2907 old_stack_pointer_delta = stack_pointer_delta;
2908 old_pending_adj = pending_stack_adjust;
2909 pending_stack_adjust = 0;
2910 /* stack_arg_under_construction says whether a stack
2911 arg is being constructed at the old stack level.
2912 Pushing the stack gets a clean outgoing argument
2913 block. */
2914 old_stack_arg_under_construction
2915 = stack_arg_under_construction;
2916 stack_arg_under_construction = 0;
2917 /* Make a new map for the new argument list. */
2918 free (stack_usage_map_buf);
2919 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
2920 stack_usage_map = stack_usage_map_buf;
2921 highest_outgoing_arg_in_use = 0;
2923 /* We can pass TRUE as the 4th argument because we just
2924 saved the stack pointer and will restore it right after
2925 the call. */
2926 allocate_dynamic_stack_space (push_size, 0,
2927 BIGGEST_ALIGNMENT, true);
2930 /* If argument evaluation might modify the stack pointer,
2931 copy the address of the argument list to a register. */
2932 for (i = 0; i < num_actuals; i++)
2933 if (args[i].pass_on_stack)
2935 argblock = copy_addr_to_reg (argblock);
2936 break;
2940 compute_argument_addresses (args, argblock, num_actuals);
2942 /* Perform stack alignment before the first push (the last arg). */
2943 if (argblock == 0
2944 && adjusted_args_size.constant > reg_parm_stack_space
2945 && adjusted_args_size.constant != unadjusted_args_size)
2947 /* When the stack adjustment is pending, we get better code
2948 by combining the adjustments. */
2949 if (pending_stack_adjust
2950 && ! inhibit_defer_pop)
2952 pending_stack_adjust
2953 = (combine_pending_stack_adjustment_and_call
2954 (unadjusted_args_size,
2955 &adjusted_args_size,
2956 preferred_unit_stack_boundary));
2957 do_pending_stack_adjust ();
2959 else if (argblock == 0)
2960 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2961 - unadjusted_args_size));
2963 /* Now that the stack is properly aligned, pops can't safely
2964 be deferred during the evaluation of the arguments. */
2965 NO_DEFER_POP;
2967 /* Record the maximum pushed stack space size. We need to delay
2968 doing it this far to take into account the optimization done
2969 by combine_pending_stack_adjustment_and_call. */
2970 if (flag_stack_usage_info
2971 && !ACCUMULATE_OUTGOING_ARGS
2972 && pass
2973 && adjusted_args_size.var == 0)
2975 int pushed = adjusted_args_size.constant + pending_stack_adjust;
2976 if (pushed > current_function_pushed_stack_size)
2977 current_function_pushed_stack_size = pushed;
2980 funexp = rtx_for_function_call (fndecl, addr);
2982 /* Figure out the register where the value, if any, will come back. */
2983 valreg = 0;
2984 if (TYPE_MODE (rettype) != VOIDmode
2985 && ! structure_value_addr)
2987 if (pcc_struct_value)
2988 valreg = hard_function_value (build_pointer_type (rettype),
2989 fndecl, NULL, (pass == 0));
2990 else
2991 valreg = hard_function_value (rettype, fndecl, fntype,
2992 (pass == 0));
2994 /* If VALREG is a PARALLEL whose first member has a zero
2995 offset, use that. This is for targets such as m68k that
2996 return the same value in multiple places. */
2997 if (GET_CODE (valreg) == PARALLEL)
2999 rtx elem = XVECEXP (valreg, 0, 0);
3000 rtx where = XEXP (elem, 0);
3001 rtx offset = XEXP (elem, 1);
3002 if (offset == const0_rtx
3003 && GET_MODE (where) == GET_MODE (valreg))
3004 valreg = where;
3008 /* Precompute all register parameters. It isn't safe to compute anything
3009 once we have started filling any specific hard regs. */
3010 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3012 if (CALL_EXPR_STATIC_CHAIN (exp))
3013 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3014 else
3015 static_chain_value = 0;
3017 #ifdef REG_PARM_STACK_SPACE
3018 /* Save the fixed argument area if it's part of the caller's frame and
3019 is clobbered by argument setup for this call. */
3020 if (ACCUMULATE_OUTGOING_ARGS && pass)
3021 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3022 &low_to_save, &high_to_save);
3023 #endif
3025 /* Now store (and compute if necessary) all non-register parms.
3026 These come before register parms, since they can require block-moves,
3027 which could clobber the registers used for register parms.
3028 Parms which have partial registers are not stored here,
3029 but we do preallocate space here if they want that. */
3031 for (i = 0; i < num_actuals; i++)
3033 if (args[i].reg == 0 || args[i].pass_on_stack)
3035 rtx before_arg = get_last_insn ();
3037 /* We don't allow passing huge (> 2^30 B) arguments
3038 by value. It would cause an overflow later on. */
3039 if (adjusted_args_size.constant
3040 >= (1 << (HOST_BITS_PER_INT - 2)))
3042 sorry ("passing too large argument on stack");
3043 continue;
3046 if (store_one_arg (&args[i], argblock, flags,
3047 adjusted_args_size.var != 0,
3048 reg_parm_stack_space)
3049 || (pass == 0
3050 && check_sibcall_argument_overlap (before_arg,
3051 &args[i], 1)))
3052 sibcall_failure = 1;
3055 if (args[i].stack)
3056 call_fusage
3057 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3058 gen_rtx_USE (VOIDmode, args[i].stack),
3059 call_fusage);
3062 /* If we have a parm that is passed in registers but not in memory
3063 and whose alignment does not permit a direct copy into registers,
3064 make a group of pseudos that correspond to each register that we
3065 will later fill. */
3066 if (STRICT_ALIGNMENT)
3067 store_unaligned_arguments_into_pseudos (args, num_actuals);
3069 /* Now store any partially-in-registers parm.
3070 This is the last place a block-move can happen. */
3071 if (reg_parm_seen)
3072 for (i = 0; i < num_actuals; i++)
3073 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3075 rtx before_arg = get_last_insn ();
3077 if (store_one_arg (&args[i], argblock, flags,
3078 adjusted_args_size.var != 0,
3079 reg_parm_stack_space)
3080 || (pass == 0
3081 && check_sibcall_argument_overlap (before_arg,
3082 &args[i], 1)))
3083 sibcall_failure = 1;
3086 /* If register arguments require space on the stack and stack space
3087 was not preallocated, allocate stack space here for arguments
3088 passed in registers. */
3089 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3090 && !ACCUMULATE_OUTGOING_ARGS
3091 && must_preallocate == 0 && reg_parm_stack_space > 0)
3092 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3094 /* Pass the function the address in which to return a
3095 structure value. */
3096 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3098 structure_value_addr
3099 = convert_memory_address (Pmode, structure_value_addr);
3100 emit_move_insn (struct_value,
3101 force_reg (Pmode,
3102 force_operand (structure_value_addr,
3103 NULL_RTX)));
3105 if (REG_P (struct_value))
3106 use_reg (&call_fusage, struct_value);
3109 after_args = get_last_insn ();
3110 funexp = prepare_call_address (fndecl, funexp, static_chain_value,
3111 &call_fusage, reg_parm_seen, pass == 0);
3113 load_register_parameters (args, num_actuals, &call_fusage, flags,
3114 pass == 0, &sibcall_failure);
3116 /* Save a pointer to the last insn before the call, so that we can
3117 later safely search backwards to find the CALL_INSN. */
3118 before_call = get_last_insn ();
3120 /* Set up next argument register. For sibling calls on machines
3121 with register windows this should be the incoming register. */
3122 if (pass == 0)
3123 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3124 VOIDmode,
3125 void_type_node,
3126 true);
3127 else
3128 next_arg_reg = targetm.calls.function_arg (args_so_far,
3129 VOIDmode, void_type_node,
3130 true);
3132 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3134 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3135 arg_nr = num_actuals - arg_nr - 1;
3136 if (arg_nr >= 0
3137 && arg_nr < num_actuals
3138 && args[arg_nr].reg
3139 && valreg
3140 && REG_P (valreg)
3141 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3142 call_fusage
3143 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3144 gen_rtx_SET (VOIDmode, valreg, args[arg_nr].reg),
3145 call_fusage);
3147 /* All arguments and registers used for the call must be set up by
3148 now! */
3150 /* Stack must be properly aligned now. */
3151 gcc_assert (!pass
3152 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3154 /* Generate the actual call instruction. */
3155 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3156 adjusted_args_size.constant, struct_value_size,
3157 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3158 flags, args_so_far);
3160 if (flag_use_caller_save)
3162 rtx last, datum = NULL_RTX;
3163 if (fndecl != NULL_TREE)
3165 datum = XEXP (DECL_RTL (fndecl), 0);
3166 gcc_assert (datum != NULL_RTX
3167 && GET_CODE (datum) == SYMBOL_REF);
3169 last = last_call_insn ();
3170 add_reg_note (last, REG_CALL_DECL, datum);
3173 /* If the call setup or the call itself overlaps with anything
3174 of the argument setup we probably clobbered our call address.
3175 In that case we can't do sibcalls. */
3176 if (pass == 0
3177 && check_sibcall_argument_overlap (after_args, 0, 0))
3178 sibcall_failure = 1;
3180 /* If a non-BLKmode value is returned at the most significant end
3181 of a register, shift the register right by the appropriate amount
3182 and update VALREG accordingly. BLKmode values are handled by the
3183 group load/store machinery below. */
3184 if (!structure_value_addr
3185 && !pcc_struct_value
3186 && TYPE_MODE (rettype) != VOIDmode
3187 && TYPE_MODE (rettype) != BLKmode
3188 && REG_P (valreg)
3189 && targetm.calls.return_in_msb (rettype))
3191 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3192 sibcall_failure = 1;
3193 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3196 if (pass && (flags & ECF_MALLOC))
3198 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3199 rtx last, insns;
3201 /* The return value from a malloc-like function is a pointer. */
3202 if (TREE_CODE (rettype) == POINTER_TYPE)
3203 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3205 emit_move_insn (temp, valreg);
3207 /* The return value from a malloc-like function can not alias
3208 anything else. */
3209 last = get_last_insn ();
3210 add_reg_note (last, REG_NOALIAS, temp);
3212 /* Write out the sequence. */
3213 insns = get_insns ();
3214 end_sequence ();
3215 emit_insn (insns);
3216 valreg = temp;
3219 /* For calls to `setjmp', etc., inform
3220 function.c:setjmp_warnings that it should complain if
3221 nonvolatile values are live. For functions that cannot
3222 return, inform flow that control does not fall through. */
3224 if ((flags & ECF_NORETURN) || pass == 0)
3226 /* The barrier must be emitted
3227 immediately after the CALL_INSN. Some ports emit more
3228 than just a CALL_INSN above, so we must search for it here. */
3230 rtx last = get_last_insn ();
3231 while (!CALL_P (last))
3233 last = PREV_INSN (last);
3234 /* There was no CALL_INSN? */
3235 gcc_assert (last != before_call);
3238 emit_barrier_after (last);
3240 /* Stack adjustments after a noreturn call are dead code.
3241 However when NO_DEFER_POP is in effect, we must preserve
3242 stack_pointer_delta. */
3243 if (inhibit_defer_pop == 0)
3245 stack_pointer_delta = old_stack_allocated;
3246 pending_stack_adjust = 0;
3250 /* If value type not void, return an rtx for the value. */
3252 if (TYPE_MODE (rettype) == VOIDmode
3253 || ignore)
3254 target = const0_rtx;
3255 else if (structure_value_addr)
3257 if (target == 0 || !MEM_P (target))
3259 target
3260 = gen_rtx_MEM (TYPE_MODE (rettype),
3261 memory_address (TYPE_MODE (rettype),
3262 structure_value_addr));
3263 set_mem_attributes (target, rettype, 1);
3266 else if (pcc_struct_value)
3268 /* This is the special C++ case where we need to
3269 know what the true target was. We take care to
3270 never use this value more than once in one expression. */
3271 target = gen_rtx_MEM (TYPE_MODE (rettype),
3272 copy_to_reg (valreg));
3273 set_mem_attributes (target, rettype, 1);
3275 /* Handle calls that return values in multiple non-contiguous locations.
3276 The Irix 6 ABI has examples of this. */
3277 else if (GET_CODE (valreg) == PARALLEL)
3279 if (target == 0)
3280 target = emit_group_move_into_temps (valreg);
3281 else if (rtx_equal_p (target, valreg))
3283 else if (GET_CODE (target) == PARALLEL)
3284 /* Handle the result of a emit_group_move_into_temps
3285 call in the previous pass. */
3286 emit_group_move (target, valreg);
3287 else
3288 emit_group_store (target, valreg, rettype,
3289 int_size_in_bytes (rettype));
3291 else if (target
3292 && GET_MODE (target) == TYPE_MODE (rettype)
3293 && GET_MODE (target) == GET_MODE (valreg))
3295 bool may_overlap = false;
3297 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3298 reg to a plain register. */
3299 if (!REG_P (target) || HARD_REGISTER_P (target))
3300 valreg = avoid_likely_spilled_reg (valreg);
3302 /* If TARGET is a MEM in the argument area, and we have
3303 saved part of the argument area, then we can't store
3304 directly into TARGET as it may get overwritten when we
3305 restore the argument save area below. Don't work too
3306 hard though and simply force TARGET to a register if it
3307 is a MEM; the optimizer is quite likely to sort it out. */
3308 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3309 for (i = 0; i < num_actuals; i++)
3310 if (args[i].save_area)
3312 may_overlap = true;
3313 break;
3316 if (may_overlap)
3317 target = copy_to_reg (valreg);
3318 else
3320 /* TARGET and VALREG cannot be equal at this point
3321 because the latter would not have
3322 REG_FUNCTION_VALUE_P true, while the former would if
3323 it were referring to the same register.
3325 If they refer to the same register, this move will be
3326 a no-op, except when function inlining is being
3327 done. */
3328 emit_move_insn (target, valreg);
3330 /* If we are setting a MEM, this code must be executed.
3331 Since it is emitted after the call insn, sibcall
3332 optimization cannot be performed in that case. */
3333 if (MEM_P (target))
3334 sibcall_failure = 1;
3337 else
3338 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3340 /* If we promoted this return value, make the proper SUBREG.
3341 TARGET might be const0_rtx here, so be careful. */
3342 if (REG_P (target)
3343 && TYPE_MODE (rettype) != BLKmode
3344 && GET_MODE (target) != TYPE_MODE (rettype))
3346 tree type = rettype;
3347 int unsignedp = TYPE_UNSIGNED (type);
3348 int offset = 0;
3349 enum machine_mode pmode;
3351 /* Ensure we promote as expected, and get the new unsignedness. */
3352 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3353 funtype, 1);
3354 gcc_assert (GET_MODE (target) == pmode);
3356 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3357 && (GET_MODE_SIZE (GET_MODE (target))
3358 > GET_MODE_SIZE (TYPE_MODE (type))))
3360 offset = GET_MODE_SIZE (GET_MODE (target))
3361 - GET_MODE_SIZE (TYPE_MODE (type));
3362 if (! BYTES_BIG_ENDIAN)
3363 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3364 else if (! WORDS_BIG_ENDIAN)
3365 offset %= UNITS_PER_WORD;
3368 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3369 SUBREG_PROMOTED_VAR_P (target) = 1;
3370 SUBREG_PROMOTED_SET (target, unsignedp);
3373 /* If size of args is variable or this was a constructor call for a stack
3374 argument, restore saved stack-pointer value. */
3376 if (old_stack_level)
3378 rtx prev = get_last_insn ();
3380 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3381 stack_pointer_delta = old_stack_pointer_delta;
3383 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3385 pending_stack_adjust = old_pending_adj;
3386 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3387 stack_arg_under_construction = old_stack_arg_under_construction;
3388 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3389 stack_usage_map = initial_stack_usage_map;
3390 sibcall_failure = 1;
3392 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3394 #ifdef REG_PARM_STACK_SPACE
3395 if (save_area)
3396 restore_fixed_argument_area (save_area, argblock,
3397 high_to_save, low_to_save);
3398 #endif
3400 /* If we saved any argument areas, restore them. */
3401 for (i = 0; i < num_actuals; i++)
3402 if (args[i].save_area)
3404 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3405 rtx stack_area
3406 = gen_rtx_MEM (save_mode,
3407 memory_address (save_mode,
3408 XEXP (args[i].stack_slot, 0)));
3410 if (save_mode != BLKmode)
3411 emit_move_insn (stack_area, args[i].save_area);
3412 else
3413 emit_block_move (stack_area, args[i].save_area,
3414 GEN_INT (args[i].locate.size.constant),
3415 BLOCK_OP_CALL_PARM);
3418 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3419 stack_usage_map = initial_stack_usage_map;
3422 /* If this was alloca, record the new stack level for nonlocal gotos.
3423 Check for the handler slots since we might not have a save area
3424 for non-local gotos. */
3426 if ((flags & ECF_MAY_BE_ALLOCA) && cfun->nonlocal_goto_save_area != 0)
3427 update_nonlocal_goto_save_area ();
3429 /* Free up storage we no longer need. */
3430 for (i = 0; i < num_actuals; ++i)
3431 free (args[i].aligned_regs);
3433 insns = get_insns ();
3434 end_sequence ();
3436 if (pass == 0)
3438 tail_call_insns = insns;
3440 /* Restore the pending stack adjustment now that we have
3441 finished generating the sibling call sequence. */
3443 restore_pending_stack_adjust (&save);
3445 /* Prepare arg structure for next iteration. */
3446 for (i = 0; i < num_actuals; i++)
3448 args[i].value = 0;
3449 args[i].aligned_regs = 0;
3450 args[i].stack = 0;
3453 sbitmap_free (stored_args_map);
3454 internal_arg_pointer_exp_state.scan_start = NULL_RTX;
3455 internal_arg_pointer_exp_state.cache.release ();
3457 else
3459 normal_call_insns = insns;
3461 /* Verify that we've deallocated all the stack we used. */
3462 gcc_assert ((flags & ECF_NORETURN)
3463 || (old_stack_allocated
3464 == stack_pointer_delta - pending_stack_adjust));
3467 /* If something prevents making this a sibling call,
3468 zero out the sequence. */
3469 if (sibcall_failure)
3470 tail_call_insns = NULL_RTX;
3471 else
3472 break;
3475 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3476 arguments too, as argument area is now clobbered by the call. */
3477 if (tail_call_insns)
3479 emit_insn (tail_call_insns);
3480 crtl->tail_call_emit = true;
3482 else
3483 emit_insn (normal_call_insns);
3485 currently_expanding_call--;
3487 free (stack_usage_map_buf);
3489 return target;
3492 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3493 this function's incoming arguments.
3495 At the start of RTL generation we know the only REG_EQUIV notes
3496 in the rtl chain are those for incoming arguments, so we can look
3497 for REG_EQUIV notes between the start of the function and the
3498 NOTE_INSN_FUNCTION_BEG.
3500 This is (slight) overkill. We could keep track of the highest
3501 argument we clobber and be more selective in removing notes, but it
3502 does not seem to be worth the effort. */
3504 void
3505 fixup_tail_calls (void)
3507 rtx insn;
3509 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3511 rtx note;
3513 /* There are never REG_EQUIV notes for the incoming arguments
3514 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3515 if (NOTE_P (insn)
3516 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3517 break;
3519 note = find_reg_note (insn, REG_EQUIV, 0);
3520 if (note)
3521 remove_note (insn, note);
3522 note = find_reg_note (insn, REG_EQUIV, 0);
3523 gcc_assert (!note);
3527 /* Traverse a list of TYPES and expand all complex types into their
3528 components. */
3529 static tree
3530 split_complex_types (tree types)
3532 tree p;
3534 /* Before allocating memory, check for the common case of no complex. */
3535 for (p = types; p; p = TREE_CHAIN (p))
3537 tree type = TREE_VALUE (p);
3538 if (TREE_CODE (type) == COMPLEX_TYPE
3539 && targetm.calls.split_complex_arg (type))
3540 goto found;
3542 return types;
3544 found:
3545 types = copy_list (types);
3547 for (p = types; p; p = TREE_CHAIN (p))
3549 tree complex_type = TREE_VALUE (p);
3551 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3552 && targetm.calls.split_complex_arg (complex_type))
3554 tree next, imag;
3556 /* Rewrite complex type with component type. */
3557 TREE_VALUE (p) = TREE_TYPE (complex_type);
3558 next = TREE_CHAIN (p);
3560 /* Add another component type for the imaginary part. */
3561 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3562 TREE_CHAIN (p) = imag;
3563 TREE_CHAIN (imag) = next;
3565 /* Skip the newly created node. */
3566 p = TREE_CHAIN (p);
3570 return types;
3573 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3574 The RETVAL parameter specifies whether return value needs to be saved, other
3575 parameters are documented in the emit_library_call function below. */
3577 static rtx
3578 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3579 enum libcall_type fn_type,
3580 enum machine_mode outmode, int nargs, va_list p)
3582 /* Total size in bytes of all the stack-parms scanned so far. */
3583 struct args_size args_size;
3584 /* Size of arguments before any adjustments (such as rounding). */
3585 struct args_size original_args_size;
3586 int argnum;
3587 rtx fun;
3588 /* Todo, choose the correct decl type of orgfun. Sadly this information
3589 isn't present here, so we default to native calling abi here. */
3590 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3591 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3592 int count;
3593 rtx argblock = 0;
3594 CUMULATIVE_ARGS args_so_far_v;
3595 cumulative_args_t args_so_far;
3596 struct arg
3598 rtx value;
3599 enum machine_mode mode;
3600 rtx reg;
3601 int partial;
3602 struct locate_and_pad_arg_data locate;
3603 rtx save_area;
3605 struct arg *argvec;
3606 int old_inhibit_defer_pop = inhibit_defer_pop;
3607 rtx call_fusage = 0;
3608 rtx mem_value = 0;
3609 rtx valreg;
3610 int pcc_struct_value = 0;
3611 int struct_value_size = 0;
3612 int flags;
3613 int reg_parm_stack_space = 0;
3614 int needed;
3615 rtx before_call;
3616 tree tfom; /* type_for_mode (outmode, 0) */
3618 #ifdef REG_PARM_STACK_SPACE
3619 /* Define the boundary of the register parm stack space that needs to be
3620 save, if any. */
3621 int low_to_save = 0, high_to_save = 0;
3622 rtx save_area = 0; /* Place that it is saved. */
3623 #endif
3625 /* Size of the stack reserved for parameter registers. */
3626 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3627 char *initial_stack_usage_map = stack_usage_map;
3628 char *stack_usage_map_buf = NULL;
3630 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3632 #ifdef REG_PARM_STACK_SPACE
3633 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3634 #endif
3636 /* By default, library functions can not throw. */
3637 flags = ECF_NOTHROW;
3639 switch (fn_type)
3641 case LCT_NORMAL:
3642 break;
3643 case LCT_CONST:
3644 flags |= ECF_CONST;
3645 break;
3646 case LCT_PURE:
3647 flags |= ECF_PURE;
3648 break;
3649 case LCT_NORETURN:
3650 flags |= ECF_NORETURN;
3651 break;
3652 case LCT_THROW:
3653 flags = ECF_NORETURN;
3654 break;
3655 case LCT_RETURNS_TWICE:
3656 flags = ECF_RETURNS_TWICE;
3657 break;
3659 fun = orgfun;
3661 /* Ensure current function's preferred stack boundary is at least
3662 what we need. */
3663 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3664 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3666 /* If this kind of value comes back in memory,
3667 decide where in memory it should come back. */
3668 if (outmode != VOIDmode)
3670 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3671 if (aggregate_value_p (tfom, 0))
3673 #ifdef PCC_STATIC_STRUCT_RETURN
3674 rtx pointer_reg
3675 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3676 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3677 pcc_struct_value = 1;
3678 if (value == 0)
3679 value = gen_reg_rtx (outmode);
3680 #else /* not PCC_STATIC_STRUCT_RETURN */
3681 struct_value_size = GET_MODE_SIZE (outmode);
3682 if (value != 0 && MEM_P (value))
3683 mem_value = value;
3684 else
3685 mem_value = assign_temp (tfom, 1, 1);
3686 #endif
3687 /* This call returns a big structure. */
3688 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3691 else
3692 tfom = void_type_node;
3694 /* ??? Unfinished: must pass the memory address as an argument. */
3696 /* Copy all the libcall-arguments out of the varargs data
3697 and into a vector ARGVEC.
3699 Compute how to pass each argument. We only support a very small subset
3700 of the full argument passing conventions to limit complexity here since
3701 library functions shouldn't have many args. */
3703 argvec = XALLOCAVEC (struct arg, nargs + 1);
3704 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3706 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3707 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3708 #else
3709 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3710 #endif
3711 args_so_far = pack_cumulative_args (&args_so_far_v);
3713 args_size.constant = 0;
3714 args_size.var = 0;
3716 count = 0;
3718 push_temp_slots ();
3720 /* If there's a structure value address to be passed,
3721 either pass it in the special place, or pass it as an extra argument. */
3722 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3724 rtx addr = XEXP (mem_value, 0);
3726 nargs++;
3728 /* Make sure it is a reasonable operand for a move or push insn. */
3729 if (!REG_P (addr) && !MEM_P (addr)
3730 && !(CONSTANT_P (addr)
3731 && targetm.legitimate_constant_p (Pmode, addr)))
3732 addr = force_operand (addr, NULL_RTX);
3734 argvec[count].value = addr;
3735 argvec[count].mode = Pmode;
3736 argvec[count].partial = 0;
3738 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3739 Pmode, NULL_TREE, true);
3740 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3741 NULL_TREE, 1) == 0);
3743 locate_and_pad_parm (Pmode, NULL_TREE,
3744 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3746 #else
3747 argvec[count].reg != 0,
3748 #endif
3749 reg_parm_stack_space, 0,
3750 NULL_TREE, &args_size, &argvec[count].locate);
3752 if (argvec[count].reg == 0 || argvec[count].partial != 0
3753 || reg_parm_stack_space > 0)
3754 args_size.constant += argvec[count].locate.size.constant;
3756 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3758 count++;
3761 for (; count < nargs; count++)
3763 rtx val = va_arg (p, rtx);
3764 enum machine_mode mode = (enum machine_mode) va_arg (p, int);
3765 int unsigned_p = 0;
3767 /* We cannot convert the arg value to the mode the library wants here;
3768 must do it earlier where we know the signedness of the arg. */
3769 gcc_assert (mode != BLKmode
3770 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3772 /* Make sure it is a reasonable operand for a move or push insn. */
3773 if (!REG_P (val) && !MEM_P (val)
3774 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3775 val = force_operand (val, NULL_RTX);
3777 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3779 rtx slot;
3780 int must_copy
3781 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3783 /* If this was a CONST function, it is now PURE since it now
3784 reads memory. */
3785 if (flags & ECF_CONST)
3787 flags &= ~ECF_CONST;
3788 flags |= ECF_PURE;
3791 if (MEM_P (val) && !must_copy)
3793 tree val_expr = MEM_EXPR (val);
3794 if (val_expr)
3795 mark_addressable (val_expr);
3796 slot = val;
3798 else
3800 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3801 1, 1);
3802 emit_move_insn (slot, val);
3805 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3806 gen_rtx_USE (VOIDmode, slot),
3807 call_fusage);
3808 if (must_copy)
3809 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3810 gen_rtx_CLOBBER (VOIDmode,
3811 slot),
3812 call_fusage);
3814 mode = Pmode;
3815 val = force_operand (XEXP (slot, 0), NULL_RTX);
3818 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
3819 argvec[count].mode = mode;
3820 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
3821 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
3822 NULL_TREE, true);
3824 argvec[count].partial
3825 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
3827 if (argvec[count].reg == 0
3828 || argvec[count].partial != 0
3829 || reg_parm_stack_space > 0)
3831 locate_and_pad_parm (mode, NULL_TREE,
3832 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3834 #else
3835 argvec[count].reg != 0,
3836 #endif
3837 reg_parm_stack_space, argvec[count].partial,
3838 NULL_TREE, &args_size, &argvec[count].locate);
3839 args_size.constant += argvec[count].locate.size.constant;
3840 gcc_assert (!argvec[count].locate.size.var);
3842 #ifdef BLOCK_REG_PADDING
3843 else
3844 /* The argument is passed entirely in registers. See at which
3845 end it should be padded. */
3846 argvec[count].locate.where_pad =
3847 BLOCK_REG_PADDING (mode, NULL_TREE,
3848 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
3849 #endif
3851 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
3854 /* If this machine requires an external definition for library
3855 functions, write one out. */
3856 assemble_external_libcall (fun);
3858 original_args_size = args_size;
3859 args_size.constant = (((args_size.constant
3860 + stack_pointer_delta
3861 + STACK_BYTES - 1)
3862 / STACK_BYTES
3863 * STACK_BYTES)
3864 - stack_pointer_delta);
3866 args_size.constant = MAX (args_size.constant,
3867 reg_parm_stack_space);
3869 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3870 args_size.constant -= reg_parm_stack_space;
3872 if (args_size.constant > crtl->outgoing_args_size)
3873 crtl->outgoing_args_size = args_size.constant;
3875 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
3877 int pushed = args_size.constant + pending_stack_adjust;
3878 if (pushed > current_function_pushed_stack_size)
3879 current_function_pushed_stack_size = pushed;
3882 if (ACCUMULATE_OUTGOING_ARGS)
3884 /* Since the stack pointer will never be pushed, it is possible for
3885 the evaluation of a parm to clobber something we have already
3886 written to the stack. Since most function calls on RISC machines
3887 do not use the stack, this is uncommon, but must work correctly.
3889 Therefore, we save any area of the stack that was already written
3890 and that we are using. Here we set up to do this by making a new
3891 stack usage map from the old one.
3893 Another approach might be to try to reorder the argument
3894 evaluations to avoid this conflicting stack usage. */
3896 needed = args_size.constant;
3898 /* Since we will be writing into the entire argument area, the
3899 map must be allocated for its entire size, not just the part that
3900 is the responsibility of the caller. */
3901 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3902 needed += reg_parm_stack_space;
3904 #ifdef ARGS_GROW_DOWNWARD
3905 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3906 needed + 1);
3907 #else
3908 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3909 needed);
3910 #endif
3911 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3912 stack_usage_map = stack_usage_map_buf;
3914 if (initial_highest_arg_in_use)
3915 memcpy (stack_usage_map, initial_stack_usage_map,
3916 initial_highest_arg_in_use);
3918 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3919 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3920 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3921 needed = 0;
3923 /* We must be careful to use virtual regs before they're instantiated,
3924 and real regs afterwards. Loop optimization, for example, can create
3925 new libcalls after we've instantiated the virtual regs, and if we
3926 use virtuals anyway, they won't match the rtl patterns. */
3928 if (virtuals_instantiated)
3929 argblock = plus_constant (Pmode, stack_pointer_rtx,
3930 STACK_POINTER_OFFSET);
3931 else
3932 argblock = virtual_outgoing_args_rtx;
3934 else
3936 if (!PUSH_ARGS)
3937 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3940 /* We push args individually in reverse order, perform stack alignment
3941 before the first push (the last arg). */
3942 if (argblock == 0)
3943 anti_adjust_stack (GEN_INT (args_size.constant
3944 - original_args_size.constant));
3946 argnum = nargs - 1;
3948 #ifdef REG_PARM_STACK_SPACE
3949 if (ACCUMULATE_OUTGOING_ARGS)
3951 /* The argument list is the property of the called routine and it
3952 may clobber it. If the fixed area has been used for previous
3953 parameters, we must save and restore it. */
3954 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3955 &low_to_save, &high_to_save);
3957 #endif
3959 /* Push the args that need to be pushed. */
3961 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3962 are to be pushed. */
3963 for (count = 0; count < nargs; count++, argnum--)
3965 enum machine_mode mode = argvec[argnum].mode;
3966 rtx val = argvec[argnum].value;
3967 rtx reg = argvec[argnum].reg;
3968 int partial = argvec[argnum].partial;
3969 unsigned int parm_align = argvec[argnum].locate.boundary;
3970 int lower_bound = 0, upper_bound = 0, i;
3972 if (! (reg != 0 && partial == 0))
3974 rtx use;
3976 if (ACCUMULATE_OUTGOING_ARGS)
3978 /* If this is being stored into a pre-allocated, fixed-size,
3979 stack area, save any previous data at that location. */
3981 #ifdef ARGS_GROW_DOWNWARD
3982 /* stack_slot is negative, but we want to index stack_usage_map
3983 with positive values. */
3984 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
3985 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3986 #else
3987 lower_bound = argvec[argnum].locate.slot_offset.constant;
3988 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3989 #endif
3991 i = lower_bound;
3992 /* Don't worry about things in the fixed argument area;
3993 it has already been saved. */
3994 if (i < reg_parm_stack_space)
3995 i = reg_parm_stack_space;
3996 while (i < upper_bound && stack_usage_map[i] == 0)
3997 i++;
3999 if (i < upper_bound)
4001 /* We need to make a save area. */
4002 unsigned int size
4003 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4004 enum machine_mode save_mode
4005 = mode_for_size (size, MODE_INT, 1);
4006 rtx adr
4007 = plus_constant (Pmode, argblock,
4008 argvec[argnum].locate.offset.constant);
4009 rtx stack_area
4010 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4012 if (save_mode == BLKmode)
4014 argvec[argnum].save_area
4015 = assign_stack_temp (BLKmode,
4016 argvec[argnum].locate.size.constant
4019 emit_block_move (validize_mem
4020 (copy_rtx (argvec[argnum].save_area)),
4021 stack_area,
4022 GEN_INT (argvec[argnum].locate.size.constant),
4023 BLOCK_OP_CALL_PARM);
4025 else
4027 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4029 emit_move_insn (argvec[argnum].save_area, stack_area);
4034 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4035 partial, reg, 0, argblock,
4036 GEN_INT (argvec[argnum].locate.offset.constant),
4037 reg_parm_stack_space,
4038 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4040 /* Now mark the segment we just used. */
4041 if (ACCUMULATE_OUTGOING_ARGS)
4042 for (i = lower_bound; i < upper_bound; i++)
4043 stack_usage_map[i] = 1;
4045 NO_DEFER_POP;
4047 /* Indicate argument access so that alias.c knows that these
4048 values are live. */
4049 if (argblock)
4050 use = plus_constant (Pmode, argblock,
4051 argvec[argnum].locate.offset.constant);
4052 else
4053 /* When arguments are pushed, trying to tell alias.c where
4054 exactly this argument is won't work, because the
4055 auto-increment causes confusion. So we merely indicate
4056 that we access something with a known mode somewhere on
4057 the stack. */
4058 use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
4059 gen_rtx_SCRATCH (Pmode));
4060 use = gen_rtx_MEM (argvec[argnum].mode, use);
4061 use = gen_rtx_USE (VOIDmode, use);
4062 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4066 argnum = nargs - 1;
4068 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4070 /* Now load any reg parms into their regs. */
4072 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4073 are to be pushed. */
4074 for (count = 0; count < nargs; count++, argnum--)
4076 enum machine_mode mode = argvec[argnum].mode;
4077 rtx val = argvec[argnum].value;
4078 rtx reg = argvec[argnum].reg;
4079 int partial = argvec[argnum].partial;
4080 #ifdef BLOCK_REG_PADDING
4081 int size = 0;
4082 #endif
4084 /* Handle calls that pass values in multiple non-contiguous
4085 locations. The PA64 has examples of this for library calls. */
4086 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4087 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4088 else if (reg != 0 && partial == 0)
4090 emit_move_insn (reg, val);
4091 #ifdef BLOCK_REG_PADDING
4092 size = GET_MODE_SIZE (argvec[argnum].mode);
4094 /* Copied from load_register_parameters. */
4096 /* Handle case where we have a value that needs shifting
4097 up to the msb. eg. a QImode value and we're padding
4098 upward on a BYTES_BIG_ENDIAN machine. */
4099 if (size < UNITS_PER_WORD
4100 && (argvec[argnum].locate.where_pad
4101 == (BYTES_BIG_ENDIAN ? upward : downward)))
4103 rtx x;
4104 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4106 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4107 report the whole reg as used. Strictly speaking, the
4108 call only uses SIZE bytes at the msb end, but it doesn't
4109 seem worth generating rtl to say that. */
4110 reg = gen_rtx_REG (word_mode, REGNO (reg));
4111 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4112 if (x != reg)
4113 emit_move_insn (reg, x);
4115 #endif
4118 NO_DEFER_POP;
4121 /* Any regs containing parms remain in use through the call. */
4122 for (count = 0; count < nargs; count++)
4124 rtx reg = argvec[count].reg;
4125 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4126 use_group_regs (&call_fusage, reg);
4127 else if (reg != 0)
4129 int partial = argvec[count].partial;
4130 if (partial)
4132 int nregs;
4133 gcc_assert (partial % UNITS_PER_WORD == 0);
4134 nregs = partial / UNITS_PER_WORD;
4135 use_regs (&call_fusage, REGNO (reg), nregs);
4137 else
4138 use_reg (&call_fusage, reg);
4142 /* Pass the function the address in which to return a structure value. */
4143 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4145 emit_move_insn (struct_value,
4146 force_reg (Pmode,
4147 force_operand (XEXP (mem_value, 0),
4148 NULL_RTX)));
4149 if (REG_P (struct_value))
4150 use_reg (&call_fusage, struct_value);
4153 /* Don't allow popping to be deferred, since then
4154 cse'ing of library calls could delete a call and leave the pop. */
4155 NO_DEFER_POP;
4156 valreg = (mem_value == 0 && outmode != VOIDmode
4157 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4159 /* Stack must be properly aligned now. */
4160 gcc_assert (!(stack_pointer_delta
4161 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4163 before_call = get_last_insn ();
4165 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4166 will set inhibit_defer_pop to that value. */
4167 /* The return type is needed to decide how many bytes the function pops.
4168 Signedness plays no role in that, so for simplicity, we pretend it's
4169 always signed. We also assume that the list of arguments passed has
4170 no impact, so we pretend it is unknown. */
4172 emit_call_1 (fun, NULL,
4173 get_identifier (XSTR (orgfun, 0)),
4174 build_function_type (tfom, NULL_TREE),
4175 original_args_size.constant, args_size.constant,
4176 struct_value_size,
4177 targetm.calls.function_arg (args_so_far,
4178 VOIDmode, void_type_node, true),
4179 valreg,
4180 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4182 if (flag_use_caller_save)
4184 rtx last, datum = orgfun;
4185 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4186 last = last_call_insn ();
4187 add_reg_note (last, REG_CALL_DECL, datum);
4190 /* Right-shift returned value if necessary. */
4191 if (!pcc_struct_value
4192 && TYPE_MODE (tfom) != BLKmode
4193 && targetm.calls.return_in_msb (tfom))
4195 shift_return_value (TYPE_MODE (tfom), false, valreg);
4196 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4199 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4200 that it should complain if nonvolatile values are live. For
4201 functions that cannot return, inform flow that control does not
4202 fall through. */
4203 if (flags & ECF_NORETURN)
4205 /* The barrier note must be emitted
4206 immediately after the CALL_INSN. Some ports emit more than
4207 just a CALL_INSN above, so we must search for it here. */
4208 rtx last = get_last_insn ();
4209 while (!CALL_P (last))
4211 last = PREV_INSN (last);
4212 /* There was no CALL_INSN? */
4213 gcc_assert (last != before_call);
4216 emit_barrier_after (last);
4219 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
4220 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
4221 if (flags & ECF_NOTHROW)
4223 rtx last = get_last_insn ();
4224 while (!CALL_P (last))
4226 last = PREV_INSN (last);
4227 /* There was no CALL_INSN? */
4228 gcc_assert (last != before_call);
4231 make_reg_eh_region_note_nothrow_nononlocal (last);
4234 /* Now restore inhibit_defer_pop to its actual original value. */
4235 OK_DEFER_POP;
4237 pop_temp_slots ();
4239 /* Copy the value to the right place. */
4240 if (outmode != VOIDmode && retval)
4242 if (mem_value)
4244 if (value == 0)
4245 value = mem_value;
4246 if (value != mem_value)
4247 emit_move_insn (value, mem_value);
4249 else if (GET_CODE (valreg) == PARALLEL)
4251 if (value == 0)
4252 value = gen_reg_rtx (outmode);
4253 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4255 else
4257 /* Convert to the proper mode if a promotion has been active. */
4258 if (GET_MODE (valreg) != outmode)
4260 int unsignedp = TYPE_UNSIGNED (tfom);
4262 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4263 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4264 == GET_MODE (valreg));
4265 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4268 if (value != 0)
4269 emit_move_insn (value, valreg);
4270 else
4271 value = valreg;
4275 if (ACCUMULATE_OUTGOING_ARGS)
4277 #ifdef REG_PARM_STACK_SPACE
4278 if (save_area)
4279 restore_fixed_argument_area (save_area, argblock,
4280 high_to_save, low_to_save);
4281 #endif
4283 /* If we saved any argument areas, restore them. */
4284 for (count = 0; count < nargs; count++)
4285 if (argvec[count].save_area)
4287 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4288 rtx adr = plus_constant (Pmode, argblock,
4289 argvec[count].locate.offset.constant);
4290 rtx stack_area = gen_rtx_MEM (save_mode,
4291 memory_address (save_mode, adr));
4293 if (save_mode == BLKmode)
4294 emit_block_move (stack_area,
4295 validize_mem
4296 (copy_rtx (argvec[count].save_area)),
4297 GEN_INT (argvec[count].locate.size.constant),
4298 BLOCK_OP_CALL_PARM);
4299 else
4300 emit_move_insn (stack_area, argvec[count].save_area);
4303 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4304 stack_usage_map = initial_stack_usage_map;
4307 free (stack_usage_map_buf);
4309 return value;
4313 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4314 (emitting the queue unless NO_QUEUE is nonzero),
4315 for a value of mode OUTMODE,
4316 with NARGS different arguments, passed as alternating rtx values
4317 and machine_modes to convert them to.
4319 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4320 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4321 other types of library calls. */
4323 void
4324 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4325 enum machine_mode outmode, int nargs, ...)
4327 va_list p;
4329 va_start (p, nargs);
4330 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4331 va_end (p);
4334 /* Like emit_library_call except that an extra argument, VALUE,
4335 comes second and says where to store the result.
4336 (If VALUE is zero, this function chooses a convenient way
4337 to return the value.
4339 This function returns an rtx for where the value is to be found.
4340 If VALUE is nonzero, VALUE is returned. */
4343 emit_library_call_value (rtx orgfun, rtx value,
4344 enum libcall_type fn_type,
4345 enum machine_mode outmode, int nargs, ...)
4347 rtx result;
4348 va_list p;
4350 va_start (p, nargs);
4351 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4352 nargs, p);
4353 va_end (p);
4355 return result;
4358 /* Store a single argument for a function call
4359 into the register or memory area where it must be passed.
4360 *ARG describes the argument value and where to pass it.
4362 ARGBLOCK is the address of the stack-block for all the arguments,
4363 or 0 on a machine where arguments are pushed individually.
4365 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4366 so must be careful about how the stack is used.
4368 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4369 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4370 that we need not worry about saving and restoring the stack.
4372 FNDECL is the declaration of the function we are calling.
4374 Return nonzero if this arg should cause sibcall failure,
4375 zero otherwise. */
4377 static int
4378 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4379 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4381 tree pval = arg->tree_value;
4382 rtx reg = 0;
4383 int partial = 0;
4384 int used = 0;
4385 int i, lower_bound = 0, upper_bound = 0;
4386 int sibcall_failure = 0;
4388 if (TREE_CODE (pval) == ERROR_MARK)
4389 return 1;
4391 /* Push a new temporary level for any temporaries we make for
4392 this argument. */
4393 push_temp_slots ();
4395 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4397 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4398 save any previous data at that location. */
4399 if (argblock && ! variable_size && arg->stack)
4401 #ifdef ARGS_GROW_DOWNWARD
4402 /* stack_slot is negative, but we want to index stack_usage_map
4403 with positive values. */
4404 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4405 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4406 else
4407 upper_bound = 0;
4409 lower_bound = upper_bound - arg->locate.size.constant;
4410 #else
4411 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4412 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4413 else
4414 lower_bound = 0;
4416 upper_bound = lower_bound + arg->locate.size.constant;
4417 #endif
4419 i = lower_bound;
4420 /* Don't worry about things in the fixed argument area;
4421 it has already been saved. */
4422 if (i < reg_parm_stack_space)
4423 i = reg_parm_stack_space;
4424 while (i < upper_bound && stack_usage_map[i] == 0)
4425 i++;
4427 if (i < upper_bound)
4429 /* We need to make a save area. */
4430 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4431 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4432 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4433 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4435 if (save_mode == BLKmode)
4437 arg->save_area
4438 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
4439 preserve_temp_slots (arg->save_area);
4440 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
4441 stack_area,
4442 GEN_INT (arg->locate.size.constant),
4443 BLOCK_OP_CALL_PARM);
4445 else
4447 arg->save_area = gen_reg_rtx (save_mode);
4448 emit_move_insn (arg->save_area, stack_area);
4454 /* If this isn't going to be placed on both the stack and in registers,
4455 set up the register and number of words. */
4456 if (! arg->pass_on_stack)
4458 if (flags & ECF_SIBCALL)
4459 reg = arg->tail_call_reg;
4460 else
4461 reg = arg->reg;
4462 partial = arg->partial;
4465 /* Being passed entirely in a register. We shouldn't be called in
4466 this case. */
4467 gcc_assert (reg == 0 || partial != 0);
4469 /* If this arg needs special alignment, don't load the registers
4470 here. */
4471 if (arg->n_aligned_regs != 0)
4472 reg = 0;
4474 /* If this is being passed partially in a register, we can't evaluate
4475 it directly into its stack slot. Otherwise, we can. */
4476 if (arg->value == 0)
4478 /* stack_arg_under_construction is nonzero if a function argument is
4479 being evaluated directly into the outgoing argument list and
4480 expand_call must take special action to preserve the argument list
4481 if it is called recursively.
4483 For scalar function arguments stack_usage_map is sufficient to
4484 determine which stack slots must be saved and restored. Scalar
4485 arguments in general have pass_on_stack == 0.
4487 If this argument is initialized by a function which takes the
4488 address of the argument (a C++ constructor or a C function
4489 returning a BLKmode structure), then stack_usage_map is
4490 insufficient and expand_call must push the stack around the
4491 function call. Such arguments have pass_on_stack == 1.
4493 Note that it is always safe to set stack_arg_under_construction,
4494 but this generates suboptimal code if set when not needed. */
4496 if (arg->pass_on_stack)
4497 stack_arg_under_construction++;
4499 arg->value = expand_expr (pval,
4500 (partial
4501 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4502 ? NULL_RTX : arg->stack,
4503 VOIDmode, EXPAND_STACK_PARM);
4505 /* If we are promoting object (or for any other reason) the mode
4506 doesn't agree, convert the mode. */
4508 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4509 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4510 arg->value, arg->unsignedp);
4512 if (arg->pass_on_stack)
4513 stack_arg_under_construction--;
4516 /* Check for overlap with already clobbered argument area. */
4517 if ((flags & ECF_SIBCALL)
4518 && MEM_P (arg->value)
4519 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4520 arg->locate.size.constant))
4521 sibcall_failure = 1;
4523 /* Don't allow anything left on stack from computation
4524 of argument to alloca. */
4525 if (flags & ECF_MAY_BE_ALLOCA)
4526 do_pending_stack_adjust ();
4528 if (arg->value == arg->stack)
4529 /* If the value is already in the stack slot, we are done. */
4531 else if (arg->mode != BLKmode)
4533 int size;
4534 unsigned int parm_align;
4536 /* Argument is a scalar, not entirely passed in registers.
4537 (If part is passed in registers, arg->partial says how much
4538 and emit_push_insn will take care of putting it there.)
4540 Push it, and if its size is less than the
4541 amount of space allocated to it,
4542 also bump stack pointer by the additional space.
4543 Note that in C the default argument promotions
4544 will prevent such mismatches. */
4546 size = GET_MODE_SIZE (arg->mode);
4547 /* Compute how much space the push instruction will push.
4548 On many machines, pushing a byte will advance the stack
4549 pointer by a halfword. */
4550 #ifdef PUSH_ROUNDING
4551 size = PUSH_ROUNDING (size);
4552 #endif
4553 used = size;
4555 /* Compute how much space the argument should get:
4556 round up to a multiple of the alignment for arguments. */
4557 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4558 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4559 / (PARM_BOUNDARY / BITS_PER_UNIT))
4560 * (PARM_BOUNDARY / BITS_PER_UNIT));
4562 /* Compute the alignment of the pushed argument. */
4563 parm_align = arg->locate.boundary;
4564 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4566 int pad = used - size;
4567 if (pad)
4569 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4570 parm_align = MIN (parm_align, pad_align);
4574 /* This isn't already where we want it on the stack, so put it there.
4575 This can either be done with push or copy insns. */
4576 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4577 parm_align, partial, reg, used - size, argblock,
4578 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4579 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4581 /* Unless this is a partially-in-register argument, the argument is now
4582 in the stack. */
4583 if (partial == 0)
4584 arg->value = arg->stack;
4586 else
4588 /* BLKmode, at least partly to be pushed. */
4590 unsigned int parm_align;
4591 int excess;
4592 rtx size_rtx;
4594 /* Pushing a nonscalar.
4595 If part is passed in registers, PARTIAL says how much
4596 and emit_push_insn will take care of putting it there. */
4598 /* Round its size up to a multiple
4599 of the allocation unit for arguments. */
4601 if (arg->locate.size.var != 0)
4603 excess = 0;
4604 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4606 else
4608 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4609 for BLKmode is careful to avoid it. */
4610 excess = (arg->locate.size.constant
4611 - int_size_in_bytes (TREE_TYPE (pval))
4612 + partial);
4613 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4614 NULL_RTX, TYPE_MODE (sizetype),
4615 EXPAND_NORMAL);
4618 parm_align = arg->locate.boundary;
4620 /* When an argument is padded down, the block is aligned to
4621 PARM_BOUNDARY, but the actual argument isn't. */
4622 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4624 if (arg->locate.size.var)
4625 parm_align = BITS_PER_UNIT;
4626 else if (excess)
4628 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4629 parm_align = MIN (parm_align, excess_align);
4633 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4635 /* emit_push_insn might not work properly if arg->value and
4636 argblock + arg->locate.offset areas overlap. */
4637 rtx x = arg->value;
4638 int i = 0;
4640 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4641 || (GET_CODE (XEXP (x, 0)) == PLUS
4642 && XEXP (XEXP (x, 0), 0) ==
4643 crtl->args.internal_arg_pointer
4644 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4646 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4647 i = INTVAL (XEXP (XEXP (x, 0), 1));
4649 /* expand_call should ensure this. */
4650 gcc_assert (!arg->locate.offset.var
4651 && arg->locate.size.var == 0
4652 && CONST_INT_P (size_rtx));
4654 if (arg->locate.offset.constant > i)
4656 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4657 sibcall_failure = 1;
4659 else if (arg->locate.offset.constant < i)
4661 /* Use arg->locate.size.constant instead of size_rtx
4662 because we only care about the part of the argument
4663 on the stack. */
4664 if (i < (arg->locate.offset.constant
4665 + arg->locate.size.constant))
4666 sibcall_failure = 1;
4668 else
4670 /* Even though they appear to be at the same location,
4671 if part of the outgoing argument is in registers,
4672 they aren't really at the same location. Check for
4673 this by making sure that the incoming size is the
4674 same as the outgoing size. */
4675 if (arg->locate.size.constant != INTVAL (size_rtx))
4676 sibcall_failure = 1;
4681 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4682 parm_align, partial, reg, excess, argblock,
4683 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4684 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4686 /* Unless this is a partially-in-register argument, the argument is now
4687 in the stack.
4689 ??? Unlike the case above, in which we want the actual
4690 address of the data, so that we can load it directly into a
4691 register, here we want the address of the stack slot, so that
4692 it's properly aligned for word-by-word copying or something
4693 like that. It's not clear that this is always correct. */
4694 if (partial == 0)
4695 arg->value = arg->stack_slot;
4698 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
4700 tree type = TREE_TYPE (arg->tree_value);
4701 arg->parallel_value
4702 = emit_group_load_into_temps (arg->reg, arg->value, type,
4703 int_size_in_bytes (type));
4706 /* Mark all slots this store used. */
4707 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4708 && argblock && ! variable_size && arg->stack)
4709 for (i = lower_bound; i < upper_bound; i++)
4710 stack_usage_map[i] = 1;
4712 /* Once we have pushed something, pops can't safely
4713 be deferred during the rest of the arguments. */
4714 NO_DEFER_POP;
4716 /* Free any temporary slots made in processing this argument. */
4717 pop_temp_slots ();
4719 return sibcall_failure;
4722 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4724 bool
4725 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED,
4726 const_tree type)
4728 if (!type)
4729 return false;
4731 /* If the type has variable size... */
4732 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4733 return true;
4735 /* If the type is marked as addressable (it is required
4736 to be constructed into the stack)... */
4737 if (TREE_ADDRESSABLE (type))
4738 return true;
4740 return false;
4743 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4744 takes trailing padding of a structure into account. */
4745 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4747 bool
4748 must_pass_in_stack_var_size_or_pad (enum machine_mode mode, const_tree type)
4750 if (!type)
4751 return false;
4753 /* If the type has variable size... */
4754 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4755 return true;
4757 /* If the type is marked as addressable (it is required
4758 to be constructed into the stack)... */
4759 if (TREE_ADDRESSABLE (type))
4760 return true;
4762 /* If the padding and mode of the type is such that a copy into
4763 a register would put it into the wrong part of the register. */
4764 if (mode == BLKmode
4765 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4766 && (FUNCTION_ARG_PADDING (mode, type)
4767 == (BYTES_BIG_ENDIAN ? upward : downward)))
4768 return true;
4770 return false;