Daily bump.
[official-gcc.git] / gcc / calls.c
blob8a23b50fc66661d8b53f0b2e3fe19a3a7ef9d156
1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989-2017 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 "backend.h"
24 #include "target.h"
25 #include "rtl.h"
26 #include "tree.h"
27 #include "gimple.h"
28 #include "predict.h"
29 #include "memmodel.h"
30 #include "tm_p.h"
31 #include "stringpool.h"
32 #include "expmed.h"
33 #include "optabs.h"
34 #include "emit-rtl.h"
35 #include "cgraph.h"
36 #include "diagnostic-core.h"
37 #include "fold-const.h"
38 #include "stor-layout.h"
39 #include "varasm.h"
40 #include "internal-fn.h"
41 #include "dojump.h"
42 #include "explow.h"
43 #include "calls.h"
44 #include "expr.h"
45 #include "output.h"
46 #include "langhooks.h"
47 #include "except.h"
48 #include "dbgcnt.h"
49 #include "rtl-iter.h"
50 #include "tree-chkp.h"
51 #include "tree-vrp.h"
52 #include "tree-ssanames.h"
53 #include "rtl-chkp.h"
54 #include "intl.h"
56 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
57 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
59 /* Data structure and subroutines used within expand_call. */
61 struct arg_data
63 /* Tree node for this argument. */
64 tree tree_value;
65 /* Mode for value; TYPE_MODE unless promoted. */
66 machine_mode mode;
67 /* Current RTL value for argument, or 0 if it isn't precomputed. */
68 rtx value;
69 /* Initially-compute RTL value for argument; only for const functions. */
70 rtx initial_value;
71 /* Register to pass this argument in, 0 if passed on stack, or an
72 PARALLEL if the arg is to be copied into multiple non-contiguous
73 registers. */
74 rtx reg;
75 /* Register to pass this argument in when generating tail call sequence.
76 This is not the same register as for normal calls on machines with
77 register windows. */
78 rtx tail_call_reg;
79 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
80 form for emit_group_move. */
81 rtx parallel_value;
82 /* If value is passed in neither reg nor stack, this field holds a number
83 of a special slot to be used. */
84 rtx special_slot;
85 /* For pointer bounds hold an index of parm bounds are bound to. -1 if
86 there is no such pointer. */
87 int pointer_arg;
88 /* If pointer_arg refers a structure, then pointer_offset holds an offset
89 of a pointer in this structure. */
90 int pointer_offset;
91 /* If REG was promoted from the actual mode of the argument expression,
92 indicates whether the promotion is sign- or zero-extended. */
93 int unsignedp;
94 /* Number of bytes to put in registers. 0 means put the whole arg
95 in registers. Also 0 if not passed in registers. */
96 int partial;
97 /* Nonzero if argument must be passed on stack.
98 Note that some arguments may be passed on the stack
99 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
100 pass_on_stack identifies arguments that *cannot* go in registers. */
101 int pass_on_stack;
102 /* Some fields packaged up for locate_and_pad_parm. */
103 struct locate_and_pad_arg_data locate;
104 /* Location on the stack at which parameter should be stored. The store
105 has already been done if STACK == VALUE. */
106 rtx stack;
107 /* Location on the stack of the start of this argument slot. This can
108 differ from STACK if this arg pads downward. This location is known
109 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
110 rtx stack_slot;
111 /* Place that this stack area has been saved, if needed. */
112 rtx save_area;
113 /* If an argument's alignment does not permit direct copying into registers,
114 copy in smaller-sized pieces into pseudos. These are stored in a
115 block pointed to by this field. The next field says how many
116 word-sized pseudos we made. */
117 rtx *aligned_regs;
118 int n_aligned_regs;
121 /* A vector of one char per byte of stack space. A byte if nonzero if
122 the corresponding stack location has been used.
123 This vector is used to prevent a function call within an argument from
124 clobbering any stack already set up. */
125 static char *stack_usage_map;
127 /* Size of STACK_USAGE_MAP. */
128 static int highest_outgoing_arg_in_use;
130 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
131 stack location's tail call argument has been already stored into the stack.
132 This bitmap is used to prevent sibling call optimization if function tries
133 to use parent's incoming argument slots when they have been already
134 overwritten with tail call arguments. */
135 static sbitmap stored_args_map;
137 /* stack_arg_under_construction is nonzero when an argument may be
138 initialized with a constructor call (including a C function that
139 returns a BLKmode struct) and expand_call must take special action
140 to make sure the object being constructed does not overlap the
141 argument list for the constructor call. */
142 static int stack_arg_under_construction;
144 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
145 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
146 cumulative_args_t);
147 static void precompute_register_parameters (int, struct arg_data *, int *);
148 static void store_bounds (struct arg_data *, struct arg_data *);
149 static int store_one_arg (struct arg_data *, rtx, int, int, int);
150 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
151 static int finalize_must_preallocate (int, int, struct arg_data *,
152 struct args_size *);
153 static void precompute_arguments (int, struct arg_data *);
154 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
155 static void initialize_argument_information (int, struct arg_data *,
156 struct args_size *, int,
157 tree, tree,
158 tree, tree, cumulative_args_t, int,
159 rtx *, int *, int *, int *,
160 bool *, bool);
161 static void compute_argument_addresses (struct arg_data *, rtx, int);
162 static rtx rtx_for_function_call (tree, tree);
163 static void load_register_parameters (struct arg_data *, int, rtx *, int,
164 int, int *);
165 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
166 machine_mode, int, va_list);
167 static int special_function_p (const_tree, int);
168 static int check_sibcall_argument_overlap_1 (rtx);
169 static int check_sibcall_argument_overlap (rtx_insn *, struct arg_data *, int);
171 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
172 unsigned int);
173 static tree split_complex_types (tree);
175 #ifdef REG_PARM_STACK_SPACE
176 static rtx save_fixed_argument_area (int, rtx, int *, int *);
177 static void restore_fixed_argument_area (rtx, rtx, int, int);
178 #endif
180 /* Force FUNEXP into a form suitable for the address of a CALL,
181 and return that as an rtx. Also load the static chain register
182 if FNDECL is a nested function.
184 CALL_FUSAGE points to a variable holding the prospective
185 CALL_INSN_FUNCTION_USAGE information. */
188 prepare_call_address (tree fndecl_or_type, rtx funexp, rtx static_chain_value,
189 rtx *call_fusage, int reg_parm_seen, int flags)
191 /* Make a valid memory address and copy constants through pseudo-regs,
192 but not for a constant address if -fno-function-cse. */
193 if (GET_CODE (funexp) != SYMBOL_REF)
195 /* If it's an indirect call by descriptor, generate code to perform
196 runtime identification of the pointer and load the descriptor. */
197 if ((flags & ECF_BY_DESCRIPTOR) && !flag_trampolines)
199 const int bit_val = targetm.calls.custom_function_descriptors;
200 rtx call_lab = gen_label_rtx ();
202 gcc_assert (fndecl_or_type && TYPE_P (fndecl_or_type));
203 fndecl_or_type
204 = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
205 fndecl_or_type);
206 DECL_STATIC_CHAIN (fndecl_or_type) = 1;
207 rtx chain = targetm.calls.static_chain (fndecl_or_type, false);
209 if (GET_MODE (funexp) != Pmode)
210 funexp = convert_memory_address (Pmode, funexp);
212 /* Avoid long live ranges around function calls. */
213 funexp = copy_to_mode_reg (Pmode, funexp);
215 if (REG_P (chain))
216 emit_insn (gen_rtx_CLOBBER (VOIDmode, chain));
218 /* Emit the runtime identification pattern. */
219 rtx mask = gen_rtx_AND (Pmode, funexp, GEN_INT (bit_val));
220 emit_cmp_and_jump_insns (mask, const0_rtx, EQ, NULL_RTX, Pmode, 1,
221 call_lab);
223 /* Statically predict the branch to very likely taken. */
224 rtx_insn *insn = get_last_insn ();
225 if (JUMP_P (insn))
226 predict_insn_def (insn, PRED_BUILTIN_EXPECT, TAKEN);
228 /* Load the descriptor. */
229 rtx mem = gen_rtx_MEM (ptr_mode,
230 plus_constant (Pmode, funexp, - bit_val));
231 MEM_NOTRAP_P (mem) = 1;
232 mem = convert_memory_address (Pmode, mem);
233 emit_move_insn (chain, mem);
235 mem = gen_rtx_MEM (ptr_mode,
236 plus_constant (Pmode, funexp,
237 POINTER_SIZE / BITS_PER_UNIT
238 - bit_val));
239 MEM_NOTRAP_P (mem) = 1;
240 mem = convert_memory_address (Pmode, mem);
241 emit_move_insn (funexp, mem);
243 emit_label (call_lab);
245 if (REG_P (chain))
247 use_reg (call_fusage, chain);
248 STATIC_CHAIN_REG_P (chain) = 1;
251 /* Make sure we're not going to be overwritten below. */
252 gcc_assert (!static_chain_value);
255 /* If we are using registers for parameters, force the
256 function address into a register now. */
257 funexp = ((reg_parm_seen
258 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
259 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
260 : memory_address (FUNCTION_MODE, funexp));
262 else
264 /* funexp could be a SYMBOL_REF represents a function pointer which is
265 of ptr_mode. In this case, it should be converted into address mode
266 to be a valid address for memory rtx pattern. See PR 64971. */
267 if (GET_MODE (funexp) != Pmode)
268 funexp = convert_memory_address (Pmode, funexp);
270 if (!(flags & ECF_SIBCALL))
272 if (!NO_FUNCTION_CSE && optimize && ! flag_no_function_cse)
273 funexp = force_reg (Pmode, funexp);
277 if (static_chain_value != 0
278 && (TREE_CODE (fndecl_or_type) != FUNCTION_DECL
279 || DECL_STATIC_CHAIN (fndecl_or_type)))
281 rtx chain;
283 chain = targetm.calls.static_chain (fndecl_or_type, false);
284 static_chain_value = convert_memory_address (Pmode, static_chain_value);
286 emit_move_insn (chain, static_chain_value);
287 if (REG_P (chain))
289 use_reg (call_fusage, chain);
290 STATIC_CHAIN_REG_P (chain) = 1;
294 return funexp;
297 /* Generate instructions to call function FUNEXP,
298 and optionally pop the results.
299 The CALL_INSN is the first insn generated.
301 FNDECL is the declaration node of the function. This is given to the
302 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
303 its own args.
305 FUNTYPE is the data type of the function. This is given to the hook
306 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
307 own args. We used to allow an identifier for library functions, but
308 that doesn't work when the return type is an aggregate type and the
309 calling convention says that the pointer to this aggregate is to be
310 popped by the callee.
312 STACK_SIZE is the number of bytes of arguments on the stack,
313 ROUNDED_STACK_SIZE is that number rounded up to
314 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
315 both to put into the call insn and to generate explicit popping
316 code if necessary.
318 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
319 It is zero if this call doesn't want a structure value.
321 NEXT_ARG_REG is the rtx that results from executing
322 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
323 just after all the args have had their registers assigned.
324 This could be whatever you like, but normally it is the first
325 arg-register beyond those used for args in this call,
326 or 0 if all the arg-registers are used in this call.
327 It is passed on to `gen_call' so you can put this info in the call insn.
329 VALREG is a hard register in which a value is returned,
330 or 0 if the call does not return a value.
332 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
333 the args to this call were processed.
334 We restore `inhibit_defer_pop' to that value.
336 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
337 denote registers used by the called function. */
339 static void
340 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
341 tree funtype ATTRIBUTE_UNUSED,
342 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
343 HOST_WIDE_INT rounded_stack_size,
344 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
345 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
346 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
347 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
349 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
350 rtx call, funmem, pat;
351 int already_popped = 0;
352 HOST_WIDE_INT n_popped = 0;
354 /* Sibling call patterns never pop arguments (no sibcall(_value)_pop
355 patterns exist). Any popping that the callee does on return will
356 be from our caller's frame rather than ours. */
357 if (!(ecf_flags & ECF_SIBCALL))
359 n_popped += targetm.calls.return_pops_args (fndecl, funtype, stack_size);
361 #ifdef CALL_POPS_ARGS
362 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
363 #endif
366 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
367 and we don't want to load it into a register as an optimization,
368 because prepare_call_address already did it if it should be done. */
369 if (GET_CODE (funexp) != SYMBOL_REF)
370 funexp = memory_address (FUNCTION_MODE, funexp);
372 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
373 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
375 tree t = fndecl;
377 /* Although a built-in FUNCTION_DECL and its non-__builtin
378 counterpart compare equal and get a shared mem_attrs, they
379 produce different dump output in compare-debug compilations,
380 if an entry gets garbage collected in one compilation, then
381 adds a different (but equivalent) entry, while the other
382 doesn't run the garbage collector at the same spot and then
383 shares the mem_attr with the equivalent entry. */
384 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
386 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
387 if (t2)
388 t = t2;
391 set_mem_expr (funmem, t);
393 else if (fntree)
394 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
396 if (ecf_flags & ECF_SIBCALL)
398 if (valreg)
399 pat = targetm.gen_sibcall_value (valreg, funmem,
400 rounded_stack_size_rtx,
401 next_arg_reg, NULL_RTX);
402 else
403 pat = targetm.gen_sibcall (funmem, rounded_stack_size_rtx,
404 next_arg_reg, GEN_INT (struct_value_size));
406 /* If the target has "call" or "call_value" insns, then prefer them
407 if no arguments are actually popped. If the target does not have
408 "call" or "call_value" insns, then we must use the popping versions
409 even if the call has no arguments to pop. */
410 else if (n_popped > 0
411 || !(valreg
412 ? targetm.have_call_value ()
413 : targetm.have_call ()))
415 rtx n_pop = GEN_INT (n_popped);
417 /* If this subroutine pops its own args, record that in the call insn
418 if possible, for the sake of frame pointer elimination. */
420 if (valreg)
421 pat = targetm.gen_call_value_pop (valreg, funmem,
422 rounded_stack_size_rtx,
423 next_arg_reg, n_pop);
424 else
425 pat = targetm.gen_call_pop (funmem, rounded_stack_size_rtx,
426 next_arg_reg, n_pop);
428 already_popped = 1;
430 else
432 if (valreg)
433 pat = targetm.gen_call_value (valreg, funmem, rounded_stack_size_rtx,
434 next_arg_reg, NULL_RTX);
435 else
436 pat = targetm.gen_call (funmem, rounded_stack_size_rtx, next_arg_reg,
437 GEN_INT (struct_value_size));
439 emit_insn (pat);
441 /* Find the call we just emitted. */
442 rtx_call_insn *call_insn = last_call_insn ();
444 /* Some target create a fresh MEM instead of reusing the one provided
445 above. Set its MEM_EXPR. */
446 call = get_call_rtx_from (call_insn);
447 if (call
448 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
449 && MEM_EXPR (funmem) != NULL_TREE)
450 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
452 /* Mark instrumented calls. */
453 if (call && fntree)
454 CALL_EXPR_WITH_BOUNDS_P (call) = CALL_WITH_BOUNDS_P (fntree);
456 /* Put the register usage information there. */
457 add_function_usage_to (call_insn, call_fusage);
459 /* If this is a const call, then set the insn's unchanging bit. */
460 if (ecf_flags & ECF_CONST)
461 RTL_CONST_CALL_P (call_insn) = 1;
463 /* If this is a pure call, then set the insn's unchanging bit. */
464 if (ecf_flags & ECF_PURE)
465 RTL_PURE_CALL_P (call_insn) = 1;
467 /* If this is a const call, then set the insn's unchanging bit. */
468 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
469 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
471 /* Create a nothrow REG_EH_REGION note, if needed. */
472 make_reg_eh_region_note (call_insn, ecf_flags, 0);
474 if (ecf_flags & ECF_NORETURN)
475 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
477 if (ecf_flags & ECF_RETURNS_TWICE)
479 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
480 cfun->calls_setjmp = 1;
483 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
485 /* Restore this now, so that we do defer pops for this call's args
486 if the context of the call as a whole permits. */
487 inhibit_defer_pop = old_inhibit_defer_pop;
489 if (n_popped > 0)
491 if (!already_popped)
492 CALL_INSN_FUNCTION_USAGE (call_insn)
493 = gen_rtx_EXPR_LIST (VOIDmode,
494 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
495 CALL_INSN_FUNCTION_USAGE (call_insn));
496 rounded_stack_size -= n_popped;
497 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
498 stack_pointer_delta -= n_popped;
500 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
502 /* If popup is needed, stack realign must use DRAP */
503 if (SUPPORTS_STACK_ALIGNMENT)
504 crtl->need_drap = true;
506 /* For noreturn calls when not accumulating outgoing args force
507 REG_ARGS_SIZE note to prevent crossjumping of calls with different
508 args sizes. */
509 else if (!ACCUMULATE_OUTGOING_ARGS && (ecf_flags & ECF_NORETURN) != 0)
510 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
512 if (!ACCUMULATE_OUTGOING_ARGS)
514 /* If returning from the subroutine does not automatically pop the args,
515 we need an instruction to pop them sooner or later.
516 Perhaps do it now; perhaps just record how much space to pop later.
518 If returning from the subroutine does pop the args, indicate that the
519 stack pointer will be changed. */
521 if (rounded_stack_size != 0)
523 if (ecf_flags & ECF_NORETURN)
524 /* Just pretend we did the pop. */
525 stack_pointer_delta -= rounded_stack_size;
526 else if (flag_defer_pop && inhibit_defer_pop == 0
527 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
528 pending_stack_adjust += rounded_stack_size;
529 else
530 adjust_stack (rounded_stack_size_rtx);
533 /* When we accumulate outgoing args, we must avoid any stack manipulations.
534 Restore the stack pointer to its original value now. Usually
535 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
536 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
537 popping variants of functions exist as well.
539 ??? We may optimize similar to defer_pop above, but it is
540 probably not worthwhile.
542 ??? It will be worthwhile to enable combine_stack_adjustments even for
543 such machines. */
544 else if (n_popped)
545 anti_adjust_stack (GEN_INT (n_popped));
548 /* Determine if the function identified by FNDECL is one with
549 special properties we wish to know about. Modify FLAGS accordingly.
551 For example, if the function might return more than one time (setjmp), then
552 set ECF_RETURNS_TWICE.
554 Set ECF_MAY_BE_ALLOCA for any memory allocation function that might allocate
555 space from the stack such as alloca. */
557 static int
558 special_function_p (const_tree fndecl, int flags)
560 tree name_decl = DECL_NAME (fndecl);
562 /* For instrumentation clones we want to derive flags
563 from the original name. */
564 if (cgraph_node::get (fndecl)
565 && cgraph_node::get (fndecl)->instrumentation_clone)
566 name_decl = DECL_NAME (cgraph_node::get (fndecl)->orig_decl);
568 if (fndecl && name_decl
569 && IDENTIFIER_LENGTH (name_decl) <= 11
570 /* Exclude functions not at the file scope, or not `extern',
571 since they are not the magic functions we would otherwise
572 think they are.
573 FIXME: this should be handled with attributes, not with this
574 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
575 because you can declare fork() inside a function if you
576 wish. */
577 && (DECL_CONTEXT (fndecl) == NULL_TREE
578 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
579 && TREE_PUBLIC (fndecl))
581 const char *name = IDENTIFIER_POINTER (name_decl);
582 const char *tname = name;
584 /* We assume that alloca will always be called by name. It
585 makes no sense to pass it as a pointer-to-function to
586 anything that does not understand its behavior. */
587 if (IDENTIFIER_LENGTH (name_decl) == 6
588 && name[0] == 'a'
589 && ! strcmp (name, "alloca"))
590 flags |= ECF_MAY_BE_ALLOCA;
592 /* Disregard prefix _ or __. */
593 if (name[0] == '_')
595 if (name[1] == '_')
596 tname += 2;
597 else
598 tname += 1;
601 /* ECF_RETURNS_TWICE is safe even for -ffreestanding. */
602 if (! strcmp (tname, "setjmp")
603 || ! strcmp (tname, "sigsetjmp")
604 || ! strcmp (name, "savectx")
605 || ! strcmp (name, "vfork")
606 || ! strcmp (name, "getcontext"))
607 flags |= ECF_RETURNS_TWICE;
610 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
611 switch (DECL_FUNCTION_CODE (fndecl))
613 case BUILT_IN_ALLOCA:
614 case BUILT_IN_ALLOCA_WITH_ALIGN:
615 flags |= ECF_MAY_BE_ALLOCA;
616 break;
617 default:
618 break;
621 return flags;
624 /* Similar to special_function_p; return a set of ERF_ flags for the
625 function FNDECL. */
626 static int
627 decl_return_flags (tree fndecl)
629 tree attr;
630 tree type = TREE_TYPE (fndecl);
631 if (!type)
632 return 0;
634 attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
635 if (!attr)
636 return 0;
638 attr = TREE_VALUE (TREE_VALUE (attr));
639 if (!attr || TREE_STRING_LENGTH (attr) < 1)
640 return 0;
642 switch (TREE_STRING_POINTER (attr)[0])
644 case '1':
645 case '2':
646 case '3':
647 case '4':
648 return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');
650 case 'm':
651 return ERF_NOALIAS;
653 case '.':
654 default:
655 return 0;
659 /* Return nonzero when FNDECL represents a call to setjmp. */
662 setjmp_call_p (const_tree fndecl)
664 if (DECL_IS_RETURNS_TWICE (fndecl))
665 return ECF_RETURNS_TWICE;
666 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
670 /* Return true if STMT may be an alloca call. */
672 bool
673 gimple_maybe_alloca_call_p (const gimple *stmt)
675 tree fndecl;
677 if (!is_gimple_call (stmt))
678 return false;
680 fndecl = gimple_call_fndecl (stmt);
681 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
682 return true;
684 return false;
687 /* Return true if STMT is a builtin alloca call. */
689 bool
690 gimple_alloca_call_p (const gimple *stmt)
692 tree fndecl;
694 if (!is_gimple_call (stmt))
695 return false;
697 fndecl = gimple_call_fndecl (stmt);
698 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
699 switch (DECL_FUNCTION_CODE (fndecl))
701 case BUILT_IN_ALLOCA:
702 case BUILT_IN_ALLOCA_WITH_ALIGN:
703 return true;
704 default:
705 break;
708 return false;
711 /* Return true when exp contains a builtin alloca call. */
713 bool
714 alloca_call_p (const_tree exp)
716 tree fndecl;
717 if (TREE_CODE (exp) == CALL_EXPR
718 && (fndecl = get_callee_fndecl (exp))
719 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
720 switch (DECL_FUNCTION_CODE (fndecl))
722 case BUILT_IN_ALLOCA:
723 case BUILT_IN_ALLOCA_WITH_ALIGN:
724 return true;
725 default:
726 break;
729 return false;
732 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
733 function. Return FALSE otherwise. */
735 static bool
736 is_tm_builtin (const_tree fndecl)
738 if (fndecl == NULL)
739 return false;
741 if (decl_is_tm_clone (fndecl))
742 return true;
744 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
746 switch (DECL_FUNCTION_CODE (fndecl))
748 case BUILT_IN_TM_COMMIT:
749 case BUILT_IN_TM_COMMIT_EH:
750 case BUILT_IN_TM_ABORT:
751 case BUILT_IN_TM_IRREVOCABLE:
752 case BUILT_IN_TM_GETTMCLONE_IRR:
753 case BUILT_IN_TM_MEMCPY:
754 case BUILT_IN_TM_MEMMOVE:
755 case BUILT_IN_TM_MEMSET:
756 CASE_BUILT_IN_TM_STORE (1):
757 CASE_BUILT_IN_TM_STORE (2):
758 CASE_BUILT_IN_TM_STORE (4):
759 CASE_BUILT_IN_TM_STORE (8):
760 CASE_BUILT_IN_TM_STORE (FLOAT):
761 CASE_BUILT_IN_TM_STORE (DOUBLE):
762 CASE_BUILT_IN_TM_STORE (LDOUBLE):
763 CASE_BUILT_IN_TM_STORE (M64):
764 CASE_BUILT_IN_TM_STORE (M128):
765 CASE_BUILT_IN_TM_STORE (M256):
766 CASE_BUILT_IN_TM_LOAD (1):
767 CASE_BUILT_IN_TM_LOAD (2):
768 CASE_BUILT_IN_TM_LOAD (4):
769 CASE_BUILT_IN_TM_LOAD (8):
770 CASE_BUILT_IN_TM_LOAD (FLOAT):
771 CASE_BUILT_IN_TM_LOAD (DOUBLE):
772 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
773 CASE_BUILT_IN_TM_LOAD (M64):
774 CASE_BUILT_IN_TM_LOAD (M128):
775 CASE_BUILT_IN_TM_LOAD (M256):
776 case BUILT_IN_TM_LOG:
777 case BUILT_IN_TM_LOG_1:
778 case BUILT_IN_TM_LOG_2:
779 case BUILT_IN_TM_LOG_4:
780 case BUILT_IN_TM_LOG_8:
781 case BUILT_IN_TM_LOG_FLOAT:
782 case BUILT_IN_TM_LOG_DOUBLE:
783 case BUILT_IN_TM_LOG_LDOUBLE:
784 case BUILT_IN_TM_LOG_M64:
785 case BUILT_IN_TM_LOG_M128:
786 case BUILT_IN_TM_LOG_M256:
787 return true;
788 default:
789 break;
792 return false;
795 /* Detect flags (function attributes) from the function decl or type node. */
798 flags_from_decl_or_type (const_tree exp)
800 int flags = 0;
802 if (DECL_P (exp))
804 /* The function exp may have the `malloc' attribute. */
805 if (DECL_IS_MALLOC (exp))
806 flags |= ECF_MALLOC;
808 /* The function exp may have the `returns_twice' attribute. */
809 if (DECL_IS_RETURNS_TWICE (exp))
810 flags |= ECF_RETURNS_TWICE;
812 /* Process the pure and const attributes. */
813 if (TREE_READONLY (exp))
814 flags |= ECF_CONST;
815 if (DECL_PURE_P (exp))
816 flags |= ECF_PURE;
817 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
818 flags |= ECF_LOOPING_CONST_OR_PURE;
820 if (DECL_IS_NOVOPS (exp))
821 flags |= ECF_NOVOPS;
822 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
823 flags |= ECF_LEAF;
824 if (lookup_attribute ("cold", DECL_ATTRIBUTES (exp)))
825 flags |= ECF_COLD;
827 if (TREE_NOTHROW (exp))
828 flags |= ECF_NOTHROW;
830 if (flag_tm)
832 if (is_tm_builtin (exp))
833 flags |= ECF_TM_BUILTIN;
834 else if ((flags & (ECF_CONST|ECF_NOVOPS)) != 0
835 || lookup_attribute ("transaction_pure",
836 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
837 flags |= ECF_TM_PURE;
840 flags = special_function_p (exp, flags);
842 else if (TYPE_P (exp))
844 if (TYPE_READONLY (exp))
845 flags |= ECF_CONST;
847 if (flag_tm
848 && ((flags & ECF_CONST) != 0
849 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
850 flags |= ECF_TM_PURE;
852 else
853 gcc_unreachable ();
855 if (TREE_THIS_VOLATILE (exp))
857 flags |= ECF_NORETURN;
858 if (flags & (ECF_CONST|ECF_PURE))
859 flags |= ECF_LOOPING_CONST_OR_PURE;
862 return flags;
865 /* Detect flags from a CALL_EXPR. */
868 call_expr_flags (const_tree t)
870 int flags;
871 tree decl = get_callee_fndecl (t);
873 if (decl)
874 flags = flags_from_decl_or_type (decl);
875 else if (CALL_EXPR_FN (t) == NULL_TREE)
876 flags = internal_fn_flags (CALL_EXPR_IFN (t));
877 else
879 tree type = TREE_TYPE (CALL_EXPR_FN (t));
880 if (type && TREE_CODE (type) == POINTER_TYPE)
881 flags = flags_from_decl_or_type (TREE_TYPE (type));
882 else
883 flags = 0;
884 if (CALL_EXPR_BY_DESCRIPTOR (t))
885 flags |= ECF_BY_DESCRIPTOR;
888 return flags;
891 /* Return true if TYPE should be passed by invisible reference. */
893 bool
894 pass_by_reference (CUMULATIVE_ARGS *ca, machine_mode mode,
895 tree type, bool named_arg)
897 if (type)
899 /* If this type contains non-trivial constructors, then it is
900 forbidden for the middle-end to create any new copies. */
901 if (TREE_ADDRESSABLE (type))
902 return true;
904 /* GCC post 3.4 passes *all* variable sized types by reference. */
905 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
906 return true;
908 /* If a record type should be passed the same as its first (and only)
909 member, use the type and mode of that member. */
910 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
912 type = TREE_TYPE (first_field (type));
913 mode = TYPE_MODE (type);
917 return targetm.calls.pass_by_reference (pack_cumulative_args (ca), mode,
918 type, named_arg);
921 /* Return true if TYPE, which is passed by reference, should be callee
922 copied instead of caller copied. */
924 bool
925 reference_callee_copied (CUMULATIVE_ARGS *ca, machine_mode mode,
926 tree type, bool named_arg)
928 if (type && TREE_ADDRESSABLE (type))
929 return false;
930 return targetm.calls.callee_copies (pack_cumulative_args (ca), mode, type,
931 named_arg);
935 /* Precompute all register parameters as described by ARGS, storing values
936 into fields within the ARGS array.
938 NUM_ACTUALS indicates the total number elements in the ARGS array.
940 Set REG_PARM_SEEN if we encounter a register parameter. */
942 static void
943 precompute_register_parameters (int num_actuals, struct arg_data *args,
944 int *reg_parm_seen)
946 int i;
948 *reg_parm_seen = 0;
950 for (i = 0; i < num_actuals; i++)
951 if (args[i].reg != 0 && ! args[i].pass_on_stack)
953 *reg_parm_seen = 1;
955 if (args[i].value == 0)
957 push_temp_slots ();
958 args[i].value = expand_normal (args[i].tree_value);
959 preserve_temp_slots (args[i].value);
960 pop_temp_slots ();
963 /* If we are to promote the function arg to a wider mode,
964 do it now. */
966 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
967 args[i].value
968 = convert_modes (args[i].mode,
969 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
970 args[i].value, args[i].unsignedp);
972 /* If the value is a non-legitimate constant, force it into a
973 pseudo now. TLS symbols sometimes need a call to resolve. */
974 if (CONSTANT_P (args[i].value)
975 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
976 args[i].value = force_reg (args[i].mode, args[i].value);
978 /* If we're going to have to load the value by parts, pull the
979 parts into pseudos. The part extraction process can involve
980 non-trivial computation. */
981 if (GET_CODE (args[i].reg) == PARALLEL)
983 tree type = TREE_TYPE (args[i].tree_value);
984 args[i].parallel_value
985 = emit_group_load_into_temps (args[i].reg, args[i].value,
986 type, int_size_in_bytes (type));
989 /* If the value is expensive, and we are inside an appropriately
990 short loop, put the value into a pseudo and then put the pseudo
991 into the hard reg.
993 For small register classes, also do this if this call uses
994 register parameters. This is to avoid reload conflicts while
995 loading the parameters registers. */
997 else if ((! (REG_P (args[i].value)
998 || (GET_CODE (args[i].value) == SUBREG
999 && REG_P (SUBREG_REG (args[i].value)))))
1000 && args[i].mode != BLKmode
1001 && (set_src_cost (args[i].value, args[i].mode,
1002 optimize_insn_for_speed_p ())
1003 > COSTS_N_INSNS (1))
1004 && ((*reg_parm_seen
1005 && targetm.small_register_classes_for_mode_p (args[i].mode))
1006 || optimize))
1007 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
1011 #ifdef REG_PARM_STACK_SPACE
1013 /* The argument list is the property of the called routine and it
1014 may clobber it. If the fixed area has been used for previous
1015 parameters, we must save and restore it. */
1017 static rtx
1018 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
1020 int low;
1021 int high;
1023 /* Compute the boundary of the area that needs to be saved, if any. */
1024 high = reg_parm_stack_space;
1025 if (ARGS_GROW_DOWNWARD)
1026 high += 1;
1028 if (high > highest_outgoing_arg_in_use)
1029 high = highest_outgoing_arg_in_use;
1031 for (low = 0; low < high; low++)
1032 if (stack_usage_map[low] != 0)
1034 int num_to_save;
1035 machine_mode save_mode;
1036 int delta;
1037 rtx addr;
1038 rtx stack_area;
1039 rtx save_area;
1041 while (stack_usage_map[--high] == 0)
1044 *low_to_save = low;
1045 *high_to_save = high;
1047 num_to_save = high - low + 1;
1048 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
1050 /* If we don't have the required alignment, must do this
1051 in BLKmode. */
1052 if ((low & (MIN (GET_MODE_SIZE (save_mode),
1053 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
1054 save_mode = BLKmode;
1056 if (ARGS_GROW_DOWNWARD)
1057 delta = -high;
1058 else
1059 delta = low;
1061 addr = plus_constant (Pmode, argblock, delta);
1062 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1064 set_mem_align (stack_area, PARM_BOUNDARY);
1065 if (save_mode == BLKmode)
1067 save_area = assign_stack_temp (BLKmode, num_to_save);
1068 emit_block_move (validize_mem (save_area), stack_area,
1069 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
1071 else
1073 save_area = gen_reg_rtx (save_mode);
1074 emit_move_insn (save_area, stack_area);
1077 return save_area;
1080 return NULL_RTX;
1083 static void
1084 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
1086 machine_mode save_mode = GET_MODE (save_area);
1087 int delta;
1088 rtx addr, stack_area;
1090 if (ARGS_GROW_DOWNWARD)
1091 delta = -high_to_save;
1092 else
1093 delta = low_to_save;
1095 addr = plus_constant (Pmode, argblock, delta);
1096 stack_area = gen_rtx_MEM (save_mode, memory_address (save_mode, addr));
1097 set_mem_align (stack_area, PARM_BOUNDARY);
1099 if (save_mode != BLKmode)
1100 emit_move_insn (stack_area, save_area);
1101 else
1102 emit_block_move (stack_area, validize_mem (save_area),
1103 GEN_INT (high_to_save - low_to_save + 1),
1104 BLOCK_OP_CALL_PARM);
1106 #endif /* REG_PARM_STACK_SPACE */
1108 /* If any elements in ARGS refer to parameters that are to be passed in
1109 registers, but not in memory, and whose alignment does not permit a
1110 direct copy into registers. Copy the values into a group of pseudos
1111 which we will later copy into the appropriate hard registers.
1113 Pseudos for each unaligned argument will be stored into the array
1114 args[argnum].aligned_regs. The caller is responsible for deallocating
1115 the aligned_regs array if it is nonzero. */
1117 static void
1118 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
1120 int i, j;
1122 for (i = 0; i < num_actuals; i++)
1123 if (args[i].reg != 0 && ! args[i].pass_on_stack
1124 && GET_CODE (args[i].reg) != PARALLEL
1125 && args[i].mode == BLKmode
1126 && MEM_P (args[i].value)
1127 && (MEM_ALIGN (args[i].value)
1128 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
1130 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1131 int endian_correction = 0;
1133 if (args[i].partial)
1135 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
1136 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
1138 else
1140 args[i].n_aligned_regs
1141 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1144 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
1146 /* Structures smaller than a word are normally aligned to the
1147 least significant byte. On a BYTES_BIG_ENDIAN machine,
1148 this means we must skip the empty high order bytes when
1149 calculating the bit offset. */
1150 if (bytes < UNITS_PER_WORD
1151 #ifdef BLOCK_REG_PADDING
1152 && (BLOCK_REG_PADDING (args[i].mode,
1153 TREE_TYPE (args[i].tree_value), 1)
1154 == downward)
1155 #else
1156 && BYTES_BIG_ENDIAN
1157 #endif
1159 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
1161 for (j = 0; j < args[i].n_aligned_regs; j++)
1163 rtx reg = gen_reg_rtx (word_mode);
1164 rtx word = operand_subword_force (args[i].value, j, BLKmode);
1165 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
1167 args[i].aligned_regs[j] = reg;
1168 word = extract_bit_field (word, bitsize, 0, 1, NULL_RTX,
1169 word_mode, word_mode, false, NULL);
1171 /* There is no need to restrict this code to loading items
1172 in TYPE_ALIGN sized hunks. The bitfield instructions can
1173 load up entire word sized registers efficiently.
1175 ??? This may not be needed anymore.
1176 We use to emit a clobber here but that doesn't let later
1177 passes optimize the instructions we emit. By storing 0 into
1178 the register later passes know the first AND to zero out the
1179 bitfield being set in the register is unnecessary. The store
1180 of 0 will be deleted as will at least the first AND. */
1182 emit_move_insn (reg, const0_rtx);
1184 bytes -= bitsize / BITS_PER_UNIT;
1185 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1186 word_mode, word, false);
1191 /* The limit set by -Walloc-larger-than=. */
1192 static GTY(()) tree alloc_object_size_limit;
1194 /* Initialize ALLOC_OBJECT_SIZE_LIMIT based on the -Walloc-size-larger-than=
1195 setting if the option is specified, or to the maximum object size if it
1196 is not. Return the initialized value. */
1198 static tree
1199 alloc_max_size (void)
1201 if (!alloc_object_size_limit)
1203 alloc_object_size_limit = TYPE_MAX_VALUE (ssizetype);
1205 if (warn_alloc_size_limit)
1207 char *end = NULL;
1208 errno = 0;
1209 unsigned HOST_WIDE_INT unit = 1;
1210 unsigned HOST_WIDE_INT limit
1211 = strtoull (warn_alloc_size_limit, &end, 10);
1213 if (!errno)
1215 if (end && *end)
1217 /* Numeric option arguments are at most INT_MAX. Make it
1218 possible to specify a larger value by accepting common
1219 suffixes. */
1220 if (!strcmp (end, "kB"))
1221 unit = 1000;
1222 else if (!strcasecmp (end, "KiB") || strcmp (end, "KB"))
1223 unit = 1024;
1224 else if (!strcmp (end, "MB"))
1225 unit = 1000LU * 1000;
1226 else if (!strcasecmp (end, "MiB"))
1227 unit = 1024LU * 1024;
1228 else if (!strcasecmp (end, "GB"))
1229 unit = 1000LU * 1000 * 1000;
1230 else if (!strcasecmp (end, "GiB"))
1231 unit = 1024LU * 1024 * 1024;
1232 else if (!strcasecmp (end, "TB"))
1233 unit = 1000LU * 1000 * 1000 * 1000;
1234 else if (!strcasecmp (end, "TiB"))
1235 unit = 1024LU * 1024 * 1024 * 1024;
1236 else if (!strcasecmp (end, "PB"))
1237 unit = 1000LU * 1000 * 1000 * 1000 * 1000;
1238 else if (!strcasecmp (end, "PiB"))
1239 unit = 1024LU * 1024 * 1024 * 1024 * 1024;
1240 else if (!strcasecmp (end, "EB"))
1241 unit = 1000LU * 1000 * 1000 * 1000 * 1000 * 1000;
1242 else if (!strcasecmp (end, "EiB"))
1243 unit = 1024LU * 1024 * 1024 * 1024 * 1024 * 1024;
1244 else
1245 unit = 0;
1248 if (unit)
1249 alloc_object_size_limit
1250 = build_int_cst (ssizetype, limit * unit);
1254 return alloc_object_size_limit;
1257 /* Return true when EXP's range can be determined and set RANGE[] to it
1258 after adjusting it if necessary to make EXP a valid size argument to
1259 an allocation function declared with attribute alloc_size (whose
1260 argument may be signed), or to a string manipulation function like
1261 memset. */
1263 bool
1264 get_size_range (tree exp, tree range[2])
1266 if (tree_fits_uhwi_p (exp))
1268 /* EXP is a constant. */
1269 range[0] = range[1] = exp;
1270 return true;
1273 wide_int min, max;
1274 enum value_range_type range_type
1275 = ((TREE_CODE (exp) == SSA_NAME && INTEGRAL_TYPE_P (TREE_TYPE (exp)))
1276 ? get_range_info (exp, &min, &max) : VR_VARYING);
1278 if (range_type == VR_VARYING)
1280 /* No range information available. */
1281 range[0] = NULL_TREE;
1282 range[1] = NULL_TREE;
1283 return false;
1286 tree exptype = TREE_TYPE (exp);
1287 unsigned expprec = TYPE_PRECISION (exptype);
1288 wide_int wzero = wi::zero (expprec);
1289 wide_int wmaxval = wide_int (TYPE_MAX_VALUE (exptype));
1291 bool signed_p = !TYPE_UNSIGNED (exptype);
1293 if (range_type == VR_ANTI_RANGE)
1295 if (signed_p)
1297 if (wi::les_p (max, wzero))
1299 /* EXP is not in a strictly negative range. That means
1300 it must be in some (not necessarily strictly) positive
1301 range which includes zero. Since in signed to unsigned
1302 conversions negative values end up converted to large
1303 positive values, and otherwise they are not valid sizes,
1304 the resulting range is in both cases [0, TYPE_MAX]. */
1305 min = wzero;
1306 max = wmaxval;
1308 else if (wi::les_p (min - 1, wzero))
1310 /* EXP is not in a negative-positive range. That means EXP
1311 is either negative, or greater than max. Since negative
1312 sizes are invalid make the range [MAX + 1, TYPE_MAX]. */
1313 min = max + 1;
1314 max = wmaxval;
1316 else
1318 max = min - 1;
1319 min = wzero;
1322 else if (wi::eq_p (wzero, min - 1))
1324 /* EXP is unsigned and not in the range [1, MAX]. That means
1325 it's either zero or greater than MAX. Even though 0 would
1326 normally be detected by -Walloc-zero set the range to
1327 [MAX, TYPE_MAX] so that when MAX is greater than the limit
1328 the whole range is diagnosed. */
1329 min = max + 1;
1330 max = wmaxval;
1332 else
1334 max = min - 1;
1335 min = wzero;
1339 range[0] = wide_int_to_tree (exptype, min);
1340 range[1] = wide_int_to_tree (exptype, max);
1342 return true;
1345 /* Diagnose a call EXP to function FN decorated with attribute alloc_size
1346 whose argument numbers given by IDX with values given by ARGS exceed
1347 the maximum object size or cause an unsigned oveflow (wrapping) when
1348 multiplied. When ARGS[0] is null the function does nothing. ARGS[1]
1349 may be null for functions like malloc, and non-null for those like
1350 calloc that are decorated with a two-argument attribute alloc_size. */
1352 void
1353 maybe_warn_alloc_args_overflow (tree fn, tree exp, tree args[2], int idx[2])
1355 /* The range each of the (up to) two arguments is known to be in. */
1356 tree argrange[2][2] = { { NULL_TREE, NULL_TREE }, { NULL_TREE, NULL_TREE } };
1358 /* Maximum object size set by -Walloc-size-larger-than= or SIZE_MAX / 2. */
1359 tree maxobjsize = alloc_max_size ();
1361 location_t loc = EXPR_LOCATION (exp);
1363 bool warned = false;
1365 /* Validate each argument individually. */
1366 for (unsigned i = 0; i != 2 && args[i]; ++i)
1368 if (TREE_CODE (args[i]) == INTEGER_CST)
1370 argrange[i][0] = args[i];
1371 argrange[i][1] = args[i];
1373 if (tree_int_cst_lt (args[i], integer_zero_node))
1375 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1376 "%Kargument %i value %qE is negative",
1377 exp, idx[i] + 1, args[i]);
1379 else if (integer_zerop (args[i]))
1381 /* Avoid issuing -Walloc-zero for allocation functions other
1382 than __builtin_alloca that are declared with attribute
1383 returns_nonnull because there's no portability risk. This
1384 avoids warning for such calls to libiberty's xmalloc and
1385 friends.
1386 Also avoid issuing the warning for calls to function named
1387 "alloca". */
1388 if ((DECL_FUNCTION_CODE (fn) == BUILT_IN_ALLOCA
1389 && IDENTIFIER_LENGTH (DECL_NAME (fn)) != 6)
1390 || (DECL_FUNCTION_CODE (fn) != BUILT_IN_ALLOCA
1391 && !lookup_attribute ("returns_nonnull",
1392 TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
1393 warned = warning_at (loc, OPT_Walloc_zero,
1394 "%Kargument %i value is zero",
1395 exp, idx[i] + 1);
1397 else if (tree_int_cst_lt (maxobjsize, args[i]))
1399 /* G++ emits calls to ::operator new[](SIZE_MAX) in C++98
1400 mode and with -fno-exceptions as a way to indicate array
1401 size overflow. There's no good way to detect C++98 here
1402 so avoid diagnosing these calls for all C++ modes. */
1403 if (i == 0
1404 && !args[1]
1405 && lang_GNU_CXX ()
1406 && DECL_IS_OPERATOR_NEW (fn)
1407 && integer_all_onesp (args[i]))
1408 continue;
1410 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1411 "%Kargument %i value %qE exceeds "
1412 "maximum object size %E",
1413 exp, idx[i] + 1, args[i], maxobjsize);
1416 else if (TREE_CODE (args[i]) == SSA_NAME
1417 && get_size_range (args[i], argrange[i]))
1419 /* Verify that the argument's range is not negative (including
1420 upper bound of zero). */
1421 if (tree_int_cst_lt (argrange[i][0], integer_zero_node)
1422 && tree_int_cst_le (argrange[i][1], integer_zero_node))
1424 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1425 "%Kargument %i range [%E, %E] is negative",
1426 exp, idx[i] + 1,
1427 argrange[i][0], argrange[i][1]);
1429 else if (tree_int_cst_lt (maxobjsize, argrange[i][0]))
1431 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1432 "%Kargument %i range [%E, %E] exceeds "
1433 "maximum object size %E",
1434 exp, idx[i] + 1,
1435 argrange[i][0], argrange[i][1],
1436 maxobjsize);
1441 if (!argrange[0])
1442 return;
1444 /* For a two-argument alloc_size, validate the product of the two
1445 arguments if both of their values or ranges are known. */
1446 if (!warned && tree_fits_uhwi_p (argrange[0][0])
1447 && argrange[1][0] && tree_fits_uhwi_p (argrange[1][0])
1448 && !integer_onep (argrange[0][0])
1449 && !integer_onep (argrange[1][0]))
1451 /* Check for overflow in the product of a function decorated with
1452 attribute alloc_size (X, Y). */
1453 unsigned szprec = TYPE_PRECISION (size_type_node);
1454 wide_int x = wi::to_wide (argrange[0][0], szprec);
1455 wide_int y = wi::to_wide (argrange[1][0], szprec);
1457 bool vflow;
1458 wide_int prod = wi::umul (x, y, &vflow);
1460 if (vflow)
1461 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1462 "%Kproduct %<%E * %E%> of arguments %i and %i "
1463 "exceeds %<SIZE_MAX%>",
1464 exp, argrange[0][0], argrange[1][0],
1465 idx[0] + 1, idx[1] + 1);
1466 else if (wi::ltu_p (wi::to_wide (maxobjsize, szprec), prod))
1467 warned = warning_at (loc, OPT_Walloc_size_larger_than_,
1468 "%Kproduct %<%E * %E%> of arguments %i and %i "
1469 "exceeds maximum object size %E",
1470 exp, argrange[0][0], argrange[1][0],
1471 idx[0] + 1, idx[1] + 1,
1472 maxobjsize);
1474 if (warned)
1476 /* Print the full range of each of the two arguments to make
1477 it clear when it is, in fact, in a range and not constant. */
1478 if (argrange[0][0] != argrange [0][1])
1479 inform (loc, "argument %i in the range [%E, %E]",
1480 idx[0] + 1, argrange[0][0], argrange[0][1]);
1481 if (argrange[1][0] != argrange [1][1])
1482 inform (loc, "argument %i in the range [%E, %E]",
1483 idx[1] + 1, argrange[1][0], argrange[1][1]);
1487 if (warned)
1489 location_t fnloc = DECL_SOURCE_LOCATION (fn);
1491 if (DECL_IS_BUILTIN (fn))
1492 inform (loc,
1493 "in a call to built-in allocation function %qD", fn);
1494 else
1495 inform (fnloc,
1496 "in a call to allocation function %qD declared here", fn);
1500 /* Issue an error if CALL_EXPR was flagged as requiring
1501 tall-call optimization. */
1503 static void
1504 maybe_complain_about_tail_call (tree call_expr, const char *reason)
1506 gcc_assert (TREE_CODE (call_expr) == CALL_EXPR);
1507 if (!CALL_EXPR_MUST_TAIL_CALL (call_expr))
1508 return;
1510 error_at (EXPR_LOCATION (call_expr), "cannot tail-call: %s", reason);
1513 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1514 CALL_EXPR EXP.
1516 NUM_ACTUALS is the total number of parameters.
1518 N_NAMED_ARGS is the total number of named arguments.
1520 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1521 value, or null.
1523 FNDECL is the tree code for the target of this call (if known)
1525 ARGS_SO_FAR holds state needed by the target to know where to place
1526 the next argument.
1528 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1529 for arguments which are passed in registers.
1531 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1532 and may be modified by this routine.
1534 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1535 flags which may be modified by this routine.
1537 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1538 that requires allocation of stack space.
1540 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1541 the thunked-to function. */
1543 static void
1544 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1545 struct arg_data *args,
1546 struct args_size *args_size,
1547 int n_named_args ATTRIBUTE_UNUSED,
1548 tree exp, tree struct_value_addr_value,
1549 tree fndecl, tree fntype,
1550 cumulative_args_t args_so_far,
1551 int reg_parm_stack_space,
1552 rtx *old_stack_level, int *old_pending_adj,
1553 int *must_preallocate, int *ecf_flags,
1554 bool *may_tailcall, bool call_from_thunk_p)
1556 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1557 location_t loc = EXPR_LOCATION (exp);
1559 /* Count arg position in order args appear. */
1560 int argpos;
1562 int i;
1564 args_size->constant = 0;
1565 args_size->var = 0;
1567 bitmap_obstack_initialize (NULL);
1569 /* In this loop, we consider args in the order they are written.
1570 We fill up ARGS from the back. */
1572 i = num_actuals - 1;
1574 int j = i, ptr_arg = -1;
1575 call_expr_arg_iterator iter;
1576 tree arg;
1577 bitmap slots = NULL;
1579 if (struct_value_addr_value)
1581 args[j].tree_value = struct_value_addr_value;
1582 j--;
1584 /* If we pass structure address then we need to
1585 create bounds for it. Since created bounds is
1586 a call statement, we expand it right here to avoid
1587 fixing all other places where it may be expanded. */
1588 if (CALL_WITH_BOUNDS_P (exp))
1590 args[j].value = gen_reg_rtx (targetm.chkp_bound_mode ());
1591 args[j].tree_value
1592 = chkp_make_bounds_for_struct_addr (struct_value_addr_value);
1593 expand_expr_real (args[j].tree_value, args[j].value, VOIDmode,
1594 EXPAND_NORMAL, 0, false);
1595 args[j].pointer_arg = j + 1;
1596 j--;
1599 argpos = 0;
1600 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1602 tree argtype = TREE_TYPE (arg);
1604 /* Remember last param with pointer and associate it
1605 with following pointer bounds. */
1606 if (CALL_WITH_BOUNDS_P (exp)
1607 && chkp_type_has_pointer (argtype))
1609 if (slots)
1610 BITMAP_FREE (slots);
1611 ptr_arg = j;
1612 if (!BOUNDED_TYPE_P (argtype))
1614 slots = BITMAP_ALLOC (NULL);
1615 chkp_find_bound_slots (argtype, slots);
1618 else if (CALL_WITH_BOUNDS_P (exp)
1619 && pass_by_reference (NULL, TYPE_MODE (argtype), argtype,
1620 argpos < n_named_args))
1622 if (slots)
1623 BITMAP_FREE (slots);
1624 ptr_arg = j;
1626 else if (POINTER_BOUNDS_TYPE_P (argtype))
1628 /* We expect bounds in instrumented calls only.
1629 Otherwise it is a sign we lost flag due to some optimization
1630 and may emit call args incorrectly. */
1631 gcc_assert (CALL_WITH_BOUNDS_P (exp));
1633 /* For structures look for the next available pointer. */
1634 if (ptr_arg != -1 && slots)
1636 unsigned bnd_no = bitmap_first_set_bit (slots);
1637 args[j].pointer_offset =
1638 bnd_no * POINTER_SIZE / BITS_PER_UNIT;
1640 bitmap_clear_bit (slots, bnd_no);
1642 /* Check we have no more pointers in the structure. */
1643 if (bitmap_empty_p (slots))
1644 BITMAP_FREE (slots);
1646 args[j].pointer_arg = ptr_arg;
1648 /* Check we covered all pointers in the previous
1649 non bounds arg. */
1650 if (!slots)
1651 ptr_arg = -1;
1653 else
1654 ptr_arg = -1;
1656 if (targetm.calls.split_complex_arg
1657 && argtype
1658 && TREE_CODE (argtype) == COMPLEX_TYPE
1659 && targetm.calls.split_complex_arg (argtype))
1661 tree subtype = TREE_TYPE (argtype);
1662 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1663 j--;
1664 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1666 else
1667 args[j].tree_value = arg;
1668 j--;
1669 argpos++;
1672 if (slots)
1673 BITMAP_FREE (slots);
1676 bitmap_obstack_release (NULL);
1678 /* Extract attribute alloc_size and if set, store the indices of
1679 the corresponding arguments in ALLOC_IDX, and then the actual
1680 argument(s) at those indices in ALLOC_ARGS. */
1681 int alloc_idx[2] = { -1, -1 };
1682 if (tree alloc_size
1683 = (fndecl ? lookup_attribute ("alloc_size",
1684 TYPE_ATTRIBUTES (TREE_TYPE (fndecl)))
1685 : NULL_TREE))
1687 tree args = TREE_VALUE (alloc_size);
1688 alloc_idx[0] = TREE_INT_CST_LOW (TREE_VALUE (args)) - 1;
1689 if (TREE_CHAIN (args))
1690 alloc_idx[1] = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (args))) - 1;
1693 /* Array for up to the two attribute alloc_size arguments. */
1694 tree alloc_args[] = { NULL_TREE, NULL_TREE };
1696 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1697 for (argpos = 0; argpos < num_actuals; i--, argpos++)
1699 tree type = TREE_TYPE (args[i].tree_value);
1700 int unsignedp;
1701 machine_mode mode;
1703 /* Replace erroneous argument with constant zero. */
1704 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1705 args[i].tree_value = integer_zero_node, type = integer_type_node;
1707 /* If TYPE is a transparent union or record, pass things the way
1708 we would pass the first field of the union or record. We have
1709 already verified that the modes are the same. */
1710 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1711 && TYPE_TRANSPARENT_AGGR (type))
1712 type = TREE_TYPE (first_field (type));
1714 /* Decide where to pass this arg.
1716 args[i].reg is nonzero if all or part is passed in registers.
1718 args[i].partial is nonzero if part but not all is passed in registers,
1719 and the exact value says how many bytes are passed in registers.
1721 args[i].pass_on_stack is nonzero if the argument must at least be
1722 computed on the stack. It may then be loaded back into registers
1723 if args[i].reg is nonzero.
1725 These decisions are driven by the FUNCTION_... macros and must agree
1726 with those made by function.c. */
1728 /* See if this argument should be passed by invisible reference. */
1729 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1730 type, argpos < n_named_args))
1732 bool callee_copies;
1733 tree base = NULL_TREE;
1735 callee_copies
1736 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1737 type, argpos < n_named_args);
1739 /* If we're compiling a thunk, pass through invisible references
1740 instead of making a copy. */
1741 if (call_from_thunk_p
1742 || (callee_copies
1743 && !TREE_ADDRESSABLE (type)
1744 && (base = get_base_address (args[i].tree_value))
1745 && TREE_CODE (base) != SSA_NAME
1746 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1748 /* We may have turned the parameter value into an SSA name.
1749 Go back to the original parameter so we can take the
1750 address. */
1751 if (TREE_CODE (args[i].tree_value) == SSA_NAME)
1753 gcc_assert (SSA_NAME_IS_DEFAULT_DEF (args[i].tree_value));
1754 args[i].tree_value = SSA_NAME_VAR (args[i].tree_value);
1755 gcc_assert (TREE_CODE (args[i].tree_value) == PARM_DECL);
1757 /* Argument setup code may have copied the value to register. We
1758 revert that optimization now because the tail call code must
1759 use the original location. */
1760 if (TREE_CODE (args[i].tree_value) == PARM_DECL
1761 && !MEM_P (DECL_RTL (args[i].tree_value))
1762 && DECL_INCOMING_RTL (args[i].tree_value)
1763 && MEM_P (DECL_INCOMING_RTL (args[i].tree_value)))
1764 set_decl_rtl (args[i].tree_value,
1765 DECL_INCOMING_RTL (args[i].tree_value));
1767 mark_addressable (args[i].tree_value);
1769 /* We can't use sibcalls if a callee-copied argument is
1770 stored in the current function's frame. */
1771 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1773 *may_tailcall = false;
1774 maybe_complain_about_tail_call (exp,
1775 "a callee-copied argument is"
1776 " stored in the current "
1777 " function's frame");
1780 args[i].tree_value = build_fold_addr_expr_loc (loc,
1781 args[i].tree_value);
1782 type = TREE_TYPE (args[i].tree_value);
1784 if (*ecf_flags & ECF_CONST)
1785 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1787 else
1789 /* We make a copy of the object and pass the address to the
1790 function being called. */
1791 rtx copy;
1793 if (!COMPLETE_TYPE_P (type)
1794 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1795 || (flag_stack_check == GENERIC_STACK_CHECK
1796 && compare_tree_int (TYPE_SIZE_UNIT (type),
1797 STACK_CHECK_MAX_VAR_SIZE) > 0))
1799 /* This is a variable-sized object. Make space on the stack
1800 for it. */
1801 rtx size_rtx = expr_size (args[i].tree_value);
1803 if (*old_stack_level == 0)
1805 emit_stack_save (SAVE_BLOCK, old_stack_level);
1806 *old_pending_adj = pending_stack_adjust;
1807 pending_stack_adjust = 0;
1810 /* We can pass TRUE as the 4th argument because we just
1811 saved the stack pointer and will restore it right after
1812 the call. */
1813 copy = allocate_dynamic_stack_space (size_rtx,
1814 TYPE_ALIGN (type),
1815 TYPE_ALIGN (type),
1816 true);
1817 copy = gen_rtx_MEM (BLKmode, copy);
1818 set_mem_attributes (copy, type, 1);
1820 else
1821 copy = assign_temp (type, 1, 0);
1823 store_expr (args[i].tree_value, copy, 0, false, false);
1825 /* Just change the const function to pure and then let
1826 the next test clear the pure based on
1827 callee_copies. */
1828 if (*ecf_flags & ECF_CONST)
1830 *ecf_flags &= ~ECF_CONST;
1831 *ecf_flags |= ECF_PURE;
1834 if (!callee_copies && *ecf_flags & ECF_PURE)
1835 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1837 args[i].tree_value
1838 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1839 type = TREE_TYPE (args[i].tree_value);
1840 *may_tailcall = false;
1841 maybe_complain_about_tail_call (exp,
1842 "argument must be passed"
1843 " by copying");
1847 unsignedp = TYPE_UNSIGNED (type);
1848 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1849 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1851 args[i].unsignedp = unsignedp;
1852 args[i].mode = mode;
1854 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1855 argpos < n_named_args);
1857 if (args[i].reg && CONST_INT_P (args[i].reg))
1859 args[i].special_slot = args[i].reg;
1860 args[i].reg = NULL;
1863 /* If this is a sibling call and the machine has register windows, the
1864 register window has to be unwinded before calling the routine, so
1865 arguments have to go into the incoming registers. */
1866 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1867 args[i].tail_call_reg
1868 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1869 argpos < n_named_args);
1870 else
1871 args[i].tail_call_reg = args[i].reg;
1873 if (args[i].reg)
1874 args[i].partial
1875 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1876 argpos < n_named_args);
1878 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1880 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1881 it means that we are to pass this arg in the register(s) designated
1882 by the PARALLEL, but also to pass it in the stack. */
1883 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1884 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1885 args[i].pass_on_stack = 1;
1887 /* If this is an addressable type, we must preallocate the stack
1888 since we must evaluate the object into its final location.
1890 If this is to be passed in both registers and the stack, it is simpler
1891 to preallocate. */
1892 if (TREE_ADDRESSABLE (type)
1893 || (args[i].pass_on_stack && args[i].reg != 0))
1894 *must_preallocate = 1;
1896 /* No stack allocation and padding for bounds. */
1897 if (POINTER_BOUNDS_P (args[i].tree_value))
1899 /* Compute the stack-size of this argument. */
1900 else if (args[i].reg == 0 || args[i].partial != 0
1901 || reg_parm_stack_space > 0
1902 || args[i].pass_on_stack)
1903 locate_and_pad_parm (mode, type,
1904 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1906 #else
1907 args[i].reg != 0,
1908 #endif
1909 reg_parm_stack_space,
1910 args[i].pass_on_stack ? 0 : args[i].partial,
1911 fndecl, args_size, &args[i].locate);
1912 #ifdef BLOCK_REG_PADDING
1913 else
1914 /* The argument is passed entirely in registers. See at which
1915 end it should be padded. */
1916 args[i].locate.where_pad =
1917 BLOCK_REG_PADDING (mode, type,
1918 int_size_in_bytes (type) <= UNITS_PER_WORD);
1919 #endif
1921 /* Update ARGS_SIZE, the total stack space for args so far. */
1923 args_size->constant += args[i].locate.size.constant;
1924 if (args[i].locate.size.var)
1925 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1927 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1928 have been used, etc. */
1930 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1931 type, argpos < n_named_args);
1933 /* Store argument values for functions decorated with attribute
1934 alloc_size. */
1935 if (argpos == alloc_idx[0])
1936 alloc_args[0] = args[i].tree_value;
1937 else if (argpos == alloc_idx[1])
1938 alloc_args[1] = args[i].tree_value;
1941 if (alloc_args[0])
1943 /* Check the arguments of functions decorated with attribute
1944 alloc_size. */
1945 maybe_warn_alloc_args_overflow (fndecl, exp, alloc_args, alloc_idx);
1949 /* Update ARGS_SIZE to contain the total size for the argument block.
1950 Return the original constant component of the argument block's size.
1952 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1953 for arguments passed in registers. */
1955 static int
1956 compute_argument_block_size (int reg_parm_stack_space,
1957 struct args_size *args_size,
1958 tree fndecl ATTRIBUTE_UNUSED,
1959 tree fntype ATTRIBUTE_UNUSED,
1960 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1962 int unadjusted_args_size = args_size->constant;
1964 /* For accumulate outgoing args mode we don't need to align, since the frame
1965 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1966 backends from generating misaligned frame sizes. */
1967 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1968 preferred_stack_boundary = STACK_BOUNDARY;
1970 /* Compute the actual size of the argument block required. The variable
1971 and constant sizes must be combined, the size may have to be rounded,
1972 and there may be a minimum required size. */
1974 if (args_size->var)
1976 args_size->var = ARGS_SIZE_TREE (*args_size);
1977 args_size->constant = 0;
1979 preferred_stack_boundary /= BITS_PER_UNIT;
1980 if (preferred_stack_boundary > 1)
1982 /* We don't handle this case yet. To handle it correctly we have
1983 to add the delta, round and subtract the delta.
1984 Currently no machine description requires this support. */
1985 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1986 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1989 if (reg_parm_stack_space > 0)
1991 args_size->var
1992 = size_binop (MAX_EXPR, args_size->var,
1993 ssize_int (reg_parm_stack_space));
1995 /* The area corresponding to register parameters is not to count in
1996 the size of the block we need. So make the adjustment. */
1997 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1998 args_size->var
1999 = size_binop (MINUS_EXPR, args_size->var,
2000 ssize_int (reg_parm_stack_space));
2003 else
2005 preferred_stack_boundary /= BITS_PER_UNIT;
2006 if (preferred_stack_boundary < 1)
2007 preferred_stack_boundary = 1;
2008 args_size->constant = (((args_size->constant
2009 + stack_pointer_delta
2010 + preferred_stack_boundary - 1)
2011 / preferred_stack_boundary
2012 * preferred_stack_boundary)
2013 - stack_pointer_delta);
2015 args_size->constant = MAX (args_size->constant,
2016 reg_parm_stack_space);
2018 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2019 args_size->constant -= reg_parm_stack_space;
2021 return unadjusted_args_size;
2024 /* Precompute parameters as needed for a function call.
2026 FLAGS is mask of ECF_* constants.
2028 NUM_ACTUALS is the number of arguments.
2030 ARGS is an array containing information for each argument; this
2031 routine fills in the INITIAL_VALUE and VALUE fields for each
2032 precomputed argument. */
2034 static void
2035 precompute_arguments (int num_actuals, struct arg_data *args)
2037 int i;
2039 /* If this is a libcall, then precompute all arguments so that we do not
2040 get extraneous instructions emitted as part of the libcall sequence. */
2042 /* If we preallocated the stack space, and some arguments must be passed
2043 on the stack, then we must precompute any parameter which contains a
2044 function call which will store arguments on the stack.
2045 Otherwise, evaluating the parameter may clobber previous parameters
2046 which have already been stored into the stack. (we have code to avoid
2047 such case by saving the outgoing stack arguments, but it results in
2048 worse code) */
2049 if (!ACCUMULATE_OUTGOING_ARGS)
2050 return;
2052 for (i = 0; i < num_actuals; i++)
2054 tree type;
2055 machine_mode mode;
2057 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
2058 continue;
2060 /* If this is an addressable type, we cannot pre-evaluate it. */
2061 type = TREE_TYPE (args[i].tree_value);
2062 gcc_assert (!TREE_ADDRESSABLE (type));
2064 args[i].initial_value = args[i].value
2065 = expand_normal (args[i].tree_value);
2067 mode = TYPE_MODE (type);
2068 if (mode != args[i].mode)
2070 int unsignedp = args[i].unsignedp;
2071 args[i].value
2072 = convert_modes (args[i].mode, mode,
2073 args[i].value, args[i].unsignedp);
2075 /* CSE will replace this only if it contains args[i].value
2076 pseudo, so convert it down to the declared mode using
2077 a SUBREG. */
2078 if (REG_P (args[i].value)
2079 && GET_MODE_CLASS (args[i].mode) == MODE_INT
2080 && promote_mode (type, mode, &unsignedp) != args[i].mode)
2082 args[i].initial_value
2083 = gen_lowpart_SUBREG (mode, args[i].value);
2084 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
2085 SUBREG_PROMOTED_SET (args[i].initial_value, args[i].unsignedp);
2091 /* Given the current state of MUST_PREALLOCATE and information about
2092 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
2093 compute and return the final value for MUST_PREALLOCATE. */
2095 static int
2096 finalize_must_preallocate (int must_preallocate, int num_actuals,
2097 struct arg_data *args, struct args_size *args_size)
2099 /* See if we have or want to preallocate stack space.
2101 If we would have to push a partially-in-regs parm
2102 before other stack parms, preallocate stack space instead.
2104 If the size of some parm is not a multiple of the required stack
2105 alignment, we must preallocate.
2107 If the total size of arguments that would otherwise create a copy in
2108 a temporary (such as a CALL) is more than half the total argument list
2109 size, preallocation is faster.
2111 Another reason to preallocate is if we have a machine (like the m88k)
2112 where stack alignment is required to be maintained between every
2113 pair of insns, not just when the call is made. However, we assume here
2114 that such machines either do not have push insns (and hence preallocation
2115 would occur anyway) or the problem is taken care of with
2116 PUSH_ROUNDING. */
2118 if (! must_preallocate)
2120 int partial_seen = 0;
2121 int copy_to_evaluate_size = 0;
2122 int i;
2124 for (i = 0; i < num_actuals && ! must_preallocate; i++)
2126 if (args[i].partial > 0 && ! args[i].pass_on_stack)
2127 partial_seen = 1;
2128 else if (partial_seen && args[i].reg == 0)
2129 must_preallocate = 1;
2130 /* We preallocate in case there are bounds passed
2131 in the bounds table to have precomputed address
2132 for bounds association. */
2133 else if (POINTER_BOUNDS_P (args[i].tree_value)
2134 && !args[i].reg)
2135 must_preallocate = 1;
2137 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
2138 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
2139 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
2140 || TREE_CODE (args[i].tree_value) == COND_EXPR
2141 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
2142 copy_to_evaluate_size
2143 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2146 if (copy_to_evaluate_size * 2 >= args_size->constant
2147 && args_size->constant > 0)
2148 must_preallocate = 1;
2150 return must_preallocate;
2153 /* If we preallocated stack space, compute the address of each argument
2154 and store it into the ARGS array.
2156 We need not ensure it is a valid memory address here; it will be
2157 validized when it is used.
2159 ARGBLOCK is an rtx for the address of the outgoing arguments. */
2161 static void
2162 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
2164 if (argblock)
2166 rtx arg_reg = argblock;
2167 int i, arg_offset = 0;
2169 if (GET_CODE (argblock) == PLUS)
2170 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
2172 for (i = 0; i < num_actuals; i++)
2174 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
2175 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
2176 rtx addr;
2177 unsigned int align, boundary;
2178 unsigned int units_on_stack = 0;
2179 machine_mode partial_mode = VOIDmode;
2181 /* Skip this parm if it will not be passed on the stack. */
2182 if (! args[i].pass_on_stack
2183 && args[i].reg != 0
2184 && args[i].partial == 0)
2185 continue;
2187 /* Pointer Bounds are never passed on the stack. */
2188 if (POINTER_BOUNDS_P (args[i].tree_value))
2189 continue;
2191 if (CONST_INT_P (offset))
2192 addr = plus_constant (Pmode, arg_reg, INTVAL (offset));
2193 else
2194 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
2196 addr = plus_constant (Pmode, addr, arg_offset);
2198 if (args[i].partial != 0)
2200 /* Only part of the parameter is being passed on the stack.
2201 Generate a simple memory reference of the correct size. */
2202 units_on_stack = args[i].locate.size.constant;
2203 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
2204 MODE_INT, 1);
2205 args[i].stack = gen_rtx_MEM (partial_mode, addr);
2206 set_mem_size (args[i].stack, units_on_stack);
2208 else
2210 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
2211 set_mem_attributes (args[i].stack,
2212 TREE_TYPE (args[i].tree_value), 1);
2214 align = BITS_PER_UNIT;
2215 boundary = args[i].locate.boundary;
2216 if (args[i].locate.where_pad != downward)
2217 align = boundary;
2218 else if (CONST_INT_P (offset))
2220 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
2221 align = least_bit_hwi (align);
2223 set_mem_align (args[i].stack, align);
2225 if (CONST_INT_P (slot_offset))
2226 addr = plus_constant (Pmode, arg_reg, INTVAL (slot_offset));
2227 else
2228 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
2230 addr = plus_constant (Pmode, addr, arg_offset);
2232 if (args[i].partial != 0)
2234 /* Only part of the parameter is being passed on the stack.
2235 Generate a simple memory reference of the correct size.
2237 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
2238 set_mem_size (args[i].stack_slot, units_on_stack);
2240 else
2242 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
2243 set_mem_attributes (args[i].stack_slot,
2244 TREE_TYPE (args[i].tree_value), 1);
2246 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
2248 /* Function incoming arguments may overlap with sibling call
2249 outgoing arguments and we cannot allow reordering of reads
2250 from function arguments with stores to outgoing arguments
2251 of sibling calls. */
2252 set_mem_alias_set (args[i].stack, 0);
2253 set_mem_alias_set (args[i].stack_slot, 0);
2258 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
2259 in a call instruction.
2261 FNDECL is the tree node for the target function. For an indirect call
2262 FNDECL will be NULL_TREE.
2264 ADDR is the operand 0 of CALL_EXPR for this call. */
2266 static rtx
2267 rtx_for_function_call (tree fndecl, tree addr)
2269 rtx funexp;
2271 /* Get the function to call, in the form of RTL. */
2272 if (fndecl)
2274 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
2275 TREE_USED (fndecl) = 1;
2277 /* Get a SYMBOL_REF rtx for the function address. */
2278 funexp = XEXP (DECL_RTL (fndecl), 0);
2280 else
2281 /* Generate an rtx (probably a pseudo-register) for the address. */
2283 push_temp_slots ();
2284 funexp = expand_normal (addr);
2285 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
2287 return funexp;
2290 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
2291 static struct
2293 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
2294 or NULL_RTX if none has been scanned yet. */
2295 rtx_insn *scan_start;
2296 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
2297 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
2298 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
2299 with fixed offset, or PC if this is with variable or unknown offset. */
2300 vec<rtx> cache;
2301 } internal_arg_pointer_exp_state;
2303 static rtx internal_arg_pointer_based_exp (const_rtx, bool);
2305 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
2306 the tail call sequence, starting with first insn that hasn't been
2307 scanned yet, and note for each pseudo on the LHS whether it is based
2308 on crtl->args.internal_arg_pointer or not, and what offset from that
2309 that pointer it has. */
2311 static void
2312 internal_arg_pointer_based_exp_scan (void)
2314 rtx_insn *insn, *scan_start = internal_arg_pointer_exp_state.scan_start;
2316 if (scan_start == NULL_RTX)
2317 insn = get_insns ();
2318 else
2319 insn = NEXT_INSN (scan_start);
2321 while (insn)
2323 rtx set = single_set (insn);
2324 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
2326 rtx val = NULL_RTX;
2327 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
2328 /* Punt on pseudos set multiple times. */
2329 if (idx < internal_arg_pointer_exp_state.cache.length ()
2330 && (internal_arg_pointer_exp_state.cache[idx]
2331 != NULL_RTX))
2332 val = pc_rtx;
2333 else
2334 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
2335 if (val != NULL_RTX)
2337 if (idx >= internal_arg_pointer_exp_state.cache.length ())
2338 internal_arg_pointer_exp_state.cache
2339 .safe_grow_cleared (idx + 1);
2340 internal_arg_pointer_exp_state.cache[idx] = val;
2343 if (NEXT_INSN (insn) == NULL_RTX)
2344 scan_start = insn;
2345 insn = NEXT_INSN (insn);
2348 internal_arg_pointer_exp_state.scan_start = scan_start;
2351 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
2352 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
2353 it with fixed offset, or PC if this is with variable or unknown offset.
2354 TOPLEVEL is true if the function is invoked at the topmost level. */
2356 static rtx
2357 internal_arg_pointer_based_exp (const_rtx rtl, bool toplevel)
2359 if (CONSTANT_P (rtl))
2360 return NULL_RTX;
2362 if (rtl == crtl->args.internal_arg_pointer)
2363 return const0_rtx;
2365 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
2366 return NULL_RTX;
2368 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
2370 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
2371 if (val == NULL_RTX || val == pc_rtx)
2372 return val;
2373 return plus_constant (Pmode, val, INTVAL (XEXP (rtl, 1)));
2376 /* When called at the topmost level, scan pseudo assignments in between the
2377 last scanned instruction in the tail call sequence and the latest insn
2378 in that sequence. */
2379 if (toplevel)
2380 internal_arg_pointer_based_exp_scan ();
2382 if (REG_P (rtl))
2384 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
2385 if (idx < internal_arg_pointer_exp_state.cache.length ())
2386 return internal_arg_pointer_exp_state.cache[idx];
2388 return NULL_RTX;
2391 subrtx_iterator::array_type array;
2392 FOR_EACH_SUBRTX (iter, array, rtl, NONCONST)
2394 const_rtx x = *iter;
2395 if (REG_P (x) && internal_arg_pointer_based_exp (x, false) != NULL_RTX)
2396 return pc_rtx;
2397 if (MEM_P (x))
2398 iter.skip_subrtxes ();
2401 return NULL_RTX;
2404 /* Return true if and only if SIZE storage units (usually bytes)
2405 starting from address ADDR overlap with already clobbered argument
2406 area. This function is used to determine if we should give up a
2407 sibcall. */
2409 static bool
2410 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
2412 HOST_WIDE_INT i;
2413 rtx val;
2415 if (bitmap_empty_p (stored_args_map))
2416 return false;
2417 val = internal_arg_pointer_based_exp (addr, true);
2418 if (val == NULL_RTX)
2419 return false;
2420 else if (val == pc_rtx)
2421 return true;
2422 else
2423 i = INTVAL (val);
2425 if (STACK_GROWS_DOWNWARD)
2426 i -= crtl->args.pretend_args_size;
2427 else
2428 i += crtl->args.pretend_args_size;
2431 if (ARGS_GROW_DOWNWARD)
2432 i = -i - size;
2434 if (size > 0)
2436 unsigned HOST_WIDE_INT k;
2438 for (k = 0; k < size; k++)
2439 if (i + k < SBITMAP_SIZE (stored_args_map)
2440 && bitmap_bit_p (stored_args_map, i + k))
2441 return true;
2444 return false;
2447 /* Do the register loads required for any wholly-register parms or any
2448 parms which are passed both on the stack and in a register. Their
2449 expressions were already evaluated.
2451 Mark all register-parms as living through the call, putting these USE
2452 insns in the CALL_INSN_FUNCTION_USAGE field.
2454 When IS_SIBCALL, perform the check_sibcall_argument_overlap
2455 checking, setting *SIBCALL_FAILURE if appropriate. */
2457 static void
2458 load_register_parameters (struct arg_data *args, int num_actuals,
2459 rtx *call_fusage, int flags, int is_sibcall,
2460 int *sibcall_failure)
2462 int i, j;
2464 for (i = 0; i < num_actuals; i++)
2466 rtx reg = ((flags & ECF_SIBCALL)
2467 ? args[i].tail_call_reg : args[i].reg);
2468 if (reg)
2470 int partial = args[i].partial;
2471 int nregs;
2472 int size = 0;
2473 rtx_insn *before_arg = get_last_insn ();
2474 /* Set non-negative if we must move a word at a time, even if
2475 just one word (e.g, partial == 4 && mode == DFmode). Set
2476 to -1 if we just use a normal move insn. This value can be
2477 zero if the argument is a zero size structure. */
2478 nregs = -1;
2479 if (GET_CODE (reg) == PARALLEL)
2481 else if (partial)
2483 gcc_assert (partial % UNITS_PER_WORD == 0);
2484 nregs = partial / UNITS_PER_WORD;
2486 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
2488 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
2489 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
2491 else
2492 size = GET_MODE_SIZE (args[i].mode);
2494 /* Handle calls that pass values in multiple non-contiguous
2495 locations. The Irix 6 ABI has examples of this. */
2497 if (GET_CODE (reg) == PARALLEL)
2498 emit_group_move (reg, args[i].parallel_value);
2500 /* If simple case, just do move. If normal partial, store_one_arg
2501 has already loaded the register for us. In all other cases,
2502 load the register(s) from memory. */
2504 else if (nregs == -1)
2506 emit_move_insn (reg, args[i].value);
2507 #ifdef BLOCK_REG_PADDING
2508 /* Handle case where we have a value that needs shifting
2509 up to the msb. eg. a QImode value and we're padding
2510 upward on a BYTES_BIG_ENDIAN machine. */
2511 if (size < UNITS_PER_WORD
2512 && (args[i].locate.where_pad
2513 == (BYTES_BIG_ENDIAN ? upward : downward)))
2515 rtx x;
2516 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2518 /* Assigning REG here rather than a temp makes CALL_FUSAGE
2519 report the whole reg as used. Strictly speaking, the
2520 call only uses SIZE bytes at the msb end, but it doesn't
2521 seem worth generating rtl to say that. */
2522 reg = gen_rtx_REG (word_mode, REGNO (reg));
2523 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
2524 if (x != reg)
2525 emit_move_insn (reg, x);
2527 #endif
2530 /* If we have pre-computed the values to put in the registers in
2531 the case of non-aligned structures, copy them in now. */
2533 else if (args[i].n_aligned_regs != 0)
2534 for (j = 0; j < args[i].n_aligned_regs; j++)
2535 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
2536 args[i].aligned_regs[j]);
2538 else if (partial == 0 || args[i].pass_on_stack)
2540 rtx mem = validize_mem (copy_rtx (args[i].value));
2542 /* Check for overlap with already clobbered argument area,
2543 providing that this has non-zero size. */
2544 if (is_sibcall
2545 && size != 0
2546 && (mem_overlaps_already_clobbered_arg_p
2547 (XEXP (args[i].value, 0), size)))
2548 *sibcall_failure = 1;
2550 if (size % UNITS_PER_WORD == 0
2551 || MEM_ALIGN (mem) % BITS_PER_WORD == 0)
2552 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
2553 else
2555 if (nregs > 1)
2556 move_block_to_reg (REGNO (reg), mem, nregs - 1,
2557 args[i].mode);
2558 rtx dest = gen_rtx_REG (word_mode, REGNO (reg) + nregs - 1);
2559 unsigned int bitoff = (nregs - 1) * BITS_PER_WORD;
2560 unsigned int bitsize = size * BITS_PER_UNIT - bitoff;
2561 rtx x = extract_bit_field (mem, bitsize, bitoff, 1, dest,
2562 word_mode, word_mode, false,
2563 NULL);
2564 if (BYTES_BIG_ENDIAN)
2565 x = expand_shift (LSHIFT_EXPR, word_mode, x,
2566 BITS_PER_WORD - bitsize, dest, 1);
2567 if (x != dest)
2568 emit_move_insn (dest, x);
2571 /* Handle a BLKmode that needs shifting. */
2572 if (nregs == 1 && size < UNITS_PER_WORD
2573 #ifdef BLOCK_REG_PADDING
2574 && args[i].locate.where_pad == downward
2575 #else
2576 && BYTES_BIG_ENDIAN
2577 #endif
2580 rtx dest = gen_rtx_REG (word_mode, REGNO (reg));
2581 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2582 enum tree_code dir = (BYTES_BIG_ENDIAN
2583 ? RSHIFT_EXPR : LSHIFT_EXPR);
2584 rtx x;
2586 x = expand_shift (dir, word_mode, dest, shift, dest, 1);
2587 if (x != dest)
2588 emit_move_insn (dest, x);
2592 /* When a parameter is a block, and perhaps in other cases, it is
2593 possible that it did a load from an argument slot that was
2594 already clobbered. */
2595 if (is_sibcall
2596 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
2597 *sibcall_failure = 1;
2599 /* Handle calls that pass values in multiple non-contiguous
2600 locations. The Irix 6 ABI has examples of this. */
2601 if (GET_CODE (reg) == PARALLEL)
2602 use_group_regs (call_fusage, reg);
2603 else if (nregs == -1)
2604 use_reg_mode (call_fusage, reg,
2605 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
2606 else if (nregs > 0)
2607 use_regs (call_fusage, REGNO (reg), nregs);
2612 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
2613 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
2614 bytes, then we would need to push some additional bytes to pad the
2615 arguments. So, we compute an adjust to the stack pointer for an
2616 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
2617 bytes. Then, when the arguments are pushed the stack will be perfectly
2618 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
2619 be popped after the call. Returns the adjustment. */
2621 static int
2622 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
2623 struct args_size *args_size,
2624 unsigned int preferred_unit_stack_boundary)
2626 /* The number of bytes to pop so that the stack will be
2627 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
2628 HOST_WIDE_INT adjustment;
2629 /* The alignment of the stack after the arguments are pushed, if we
2630 just pushed the arguments without adjust the stack here. */
2631 unsigned HOST_WIDE_INT unadjusted_alignment;
2633 unadjusted_alignment
2634 = ((stack_pointer_delta + unadjusted_args_size)
2635 % preferred_unit_stack_boundary);
2637 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
2638 as possible -- leaving just enough left to cancel out the
2639 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
2640 PENDING_STACK_ADJUST is non-negative, and congruent to
2641 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2643 /* Begin by trying to pop all the bytes. */
2644 unadjusted_alignment
2645 = (unadjusted_alignment
2646 - (pending_stack_adjust % preferred_unit_stack_boundary));
2647 adjustment = pending_stack_adjust;
2648 /* Push enough additional bytes that the stack will be aligned
2649 after the arguments are pushed. */
2650 if (preferred_unit_stack_boundary > 1 && unadjusted_alignment)
2651 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2653 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2654 bytes after the call. The right number is the entire
2655 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2656 by the arguments in the first place. */
2657 args_size->constant
2658 = pending_stack_adjust - adjustment + unadjusted_args_size;
2660 return adjustment;
2663 /* Scan X expression if it does not dereference any argument slots
2664 we already clobbered by tail call arguments (as noted in stored_args_map
2665 bitmap).
2666 Return nonzero if X expression dereferences such argument slots,
2667 zero otherwise. */
2669 static int
2670 check_sibcall_argument_overlap_1 (rtx x)
2672 RTX_CODE code;
2673 int i, j;
2674 const char *fmt;
2676 if (x == NULL_RTX)
2677 return 0;
2679 code = GET_CODE (x);
2681 /* We need not check the operands of the CALL expression itself. */
2682 if (code == CALL)
2683 return 0;
2685 if (code == MEM)
2686 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2687 GET_MODE_SIZE (GET_MODE (x)));
2689 /* Scan all subexpressions. */
2690 fmt = GET_RTX_FORMAT (code);
2691 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2693 if (*fmt == 'e')
2695 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2696 return 1;
2698 else if (*fmt == 'E')
2700 for (j = 0; j < XVECLEN (x, i); j++)
2701 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2702 return 1;
2705 return 0;
2708 /* Scan sequence after INSN if it does not dereference any argument slots
2709 we already clobbered by tail call arguments (as noted in stored_args_map
2710 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2711 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2712 should be 0). Return nonzero if sequence after INSN dereferences such argument
2713 slots, zero otherwise. */
2715 static int
2716 check_sibcall_argument_overlap (rtx_insn *insn, struct arg_data *arg,
2717 int mark_stored_args_map)
2719 int low, high;
2721 if (insn == NULL_RTX)
2722 insn = get_insns ();
2723 else
2724 insn = NEXT_INSN (insn);
2726 for (; insn; insn = NEXT_INSN (insn))
2727 if (INSN_P (insn)
2728 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2729 break;
2731 if (mark_stored_args_map)
2733 if (ARGS_GROW_DOWNWARD)
2734 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2735 else
2736 low = arg->locate.slot_offset.constant;
2738 for (high = low + arg->locate.size.constant; low < high; low++)
2739 bitmap_set_bit (stored_args_map, low);
2741 return insn != NULL_RTX;
2744 /* Given that a function returns a value of mode MODE at the most
2745 significant end of hard register VALUE, shift VALUE left or right
2746 as specified by LEFT_P. Return true if some action was needed. */
2748 bool
2749 shift_return_value (machine_mode mode, bool left_p, rtx value)
2751 HOST_WIDE_INT shift;
2753 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2754 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2755 if (shift == 0)
2756 return false;
2758 /* Use ashr rather than lshr for right shifts. This is for the benefit
2759 of the MIPS port, which requires SImode values to be sign-extended
2760 when stored in 64-bit registers. */
2761 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2762 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2763 gcc_unreachable ();
2764 return true;
2767 /* If X is a likely-spilled register value, copy it to a pseudo
2768 register and return that register. Return X otherwise. */
2770 static rtx
2771 avoid_likely_spilled_reg (rtx x)
2773 rtx new_rtx;
2775 if (REG_P (x)
2776 && HARD_REGISTER_P (x)
2777 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2779 /* Make sure that we generate a REG rather than a CONCAT.
2780 Moves into CONCATs can need nontrivial instructions,
2781 and the whole point of this function is to avoid
2782 using the hard register directly in such a situation. */
2783 generating_concat_p = 0;
2784 new_rtx = gen_reg_rtx (GET_MODE (x));
2785 generating_concat_p = 1;
2786 emit_move_insn (new_rtx, x);
2787 return new_rtx;
2789 return x;
2792 /* Helper function for expand_call.
2793 Return false is EXP is not implementable as a sibling call. */
2795 static bool
2796 can_implement_as_sibling_call_p (tree exp,
2797 rtx structure_value_addr,
2798 tree funtype,
2799 int reg_parm_stack_space ATTRIBUTE_UNUSED,
2800 tree fndecl,
2801 int flags,
2802 tree addr,
2803 const args_size &args_size)
2805 if (!targetm.have_sibcall_epilogue ())
2807 maybe_complain_about_tail_call
2808 (exp,
2809 "machine description does not have"
2810 " a sibcall_epilogue instruction pattern");
2811 return false;
2814 /* Doing sibling call optimization needs some work, since
2815 structure_value_addr can be allocated on the stack.
2816 It does not seem worth the effort since few optimizable
2817 sibling calls will return a structure. */
2818 if (structure_value_addr != NULL_RTX)
2820 maybe_complain_about_tail_call (exp, "callee returns a structure");
2821 return false;
2824 #ifdef REG_PARM_STACK_SPACE
2825 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2826 if (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2827 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl))
2828 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (current_function_decl)))
2830 maybe_complain_about_tail_call (exp,
2831 "inconsistent size of stack space"
2832 " allocated for arguments which are"
2833 " passed in registers");
2834 return false;
2836 #endif
2838 /* Check whether the target is able to optimize the call
2839 into a sibcall. */
2840 if (!targetm.function_ok_for_sibcall (fndecl, exp))
2842 maybe_complain_about_tail_call (exp,
2843 "target is not able to optimize the"
2844 " call into a sibling call");
2845 return false;
2848 /* Functions that do not return exactly once may not be sibcall
2849 optimized. */
2850 if (flags & ECF_RETURNS_TWICE)
2852 maybe_complain_about_tail_call (exp, "callee returns twice");
2853 return false;
2855 if (flags & ECF_NORETURN)
2857 maybe_complain_about_tail_call (exp, "callee does not return");
2858 return false;
2861 if (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr))))
2863 maybe_complain_about_tail_call (exp, "volatile function type");
2864 return false;
2867 /* If the called function is nested in the current one, it might access
2868 some of the caller's arguments, but could clobber them beforehand if
2869 the argument areas are shared. */
2870 if (fndecl && decl_function_context (fndecl) == current_function_decl)
2872 maybe_complain_about_tail_call (exp, "nested function");
2873 return false;
2876 /* If this function requires more stack slots than the current
2877 function, we cannot change it into a sibling call.
2878 crtl->args.pretend_args_size is not part of the
2879 stack allocated by our caller. */
2880 if (args_size.constant > (crtl->args.size - crtl->args.pretend_args_size))
2882 maybe_complain_about_tail_call (exp,
2883 "callee required more stack slots"
2884 " than the caller");
2885 return false;
2888 /* If the callee pops its own arguments, then it must pop exactly
2889 the same number of arguments as the current function. */
2890 if (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2891 != targetm.calls.return_pops_args (current_function_decl,
2892 TREE_TYPE (current_function_decl),
2893 crtl->args.size))
2895 maybe_complain_about_tail_call (exp,
2896 "inconsistent number of"
2897 " popped arguments");
2898 return false;
2901 if (!lang_hooks.decls.ok_for_sibcall (fndecl))
2903 maybe_complain_about_tail_call (exp, "frontend does not support"
2904 " sibling call");
2905 return false;
2908 /* All checks passed. */
2909 return true;
2912 /* Generate all the code for a CALL_EXPR exp
2913 and return an rtx for its value.
2914 Store the value in TARGET (specified as an rtx) if convenient.
2915 If the value is stored in TARGET then TARGET is returned.
2916 If IGNORE is nonzero, then we ignore the value of the function call. */
2919 expand_call (tree exp, rtx target, int ignore)
2921 /* Nonzero if we are currently expanding a call. */
2922 static int currently_expanding_call = 0;
2924 /* RTX for the function to be called. */
2925 rtx funexp;
2926 /* Sequence of insns to perform a normal "call". */
2927 rtx_insn *normal_call_insns = NULL;
2928 /* Sequence of insns to perform a tail "call". */
2929 rtx_insn *tail_call_insns = NULL;
2930 /* Data type of the function. */
2931 tree funtype;
2932 tree type_arg_types;
2933 tree rettype;
2934 /* Declaration of the function being called,
2935 or 0 if the function is computed (not known by name). */
2936 tree fndecl = 0;
2937 /* The type of the function being called. */
2938 tree fntype;
2939 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2940 bool must_tail_call = CALL_EXPR_MUST_TAIL_CALL (exp);
2941 int pass;
2943 /* Register in which non-BLKmode value will be returned,
2944 or 0 if no value or if value is BLKmode. */
2945 rtx valreg;
2946 /* Register(s) in which bounds are returned. */
2947 rtx valbnd = NULL;
2948 /* Address where we should return a BLKmode value;
2949 0 if value not BLKmode. */
2950 rtx structure_value_addr = 0;
2951 /* Nonzero if that address is being passed by treating it as
2952 an extra, implicit first parameter. Otherwise,
2953 it is passed by being copied directly into struct_value_rtx. */
2954 int structure_value_addr_parm = 0;
2955 /* Holds the value of implicit argument for the struct value. */
2956 tree structure_value_addr_value = NULL_TREE;
2957 /* Size of aggregate value wanted, or zero if none wanted
2958 or if we are using the non-reentrant PCC calling convention
2959 or expecting the value in registers. */
2960 HOST_WIDE_INT struct_value_size = 0;
2961 /* Nonzero if called function returns an aggregate in memory PCC style,
2962 by returning the address of where to find it. */
2963 int pcc_struct_value = 0;
2964 rtx struct_value = 0;
2966 /* Number of actual parameters in this call, including struct value addr. */
2967 int num_actuals;
2968 /* Number of named args. Args after this are anonymous ones
2969 and they must all go on the stack. */
2970 int n_named_args;
2971 /* Number of complex actual arguments that need to be split. */
2972 int num_complex_actuals = 0;
2974 /* Vector of information about each argument.
2975 Arguments are numbered in the order they will be pushed,
2976 not the order they are written. */
2977 struct arg_data *args;
2979 /* Total size in bytes of all the stack-parms scanned so far. */
2980 struct args_size args_size;
2981 struct args_size adjusted_args_size;
2982 /* Size of arguments before any adjustments (such as rounding). */
2983 int unadjusted_args_size;
2984 /* Data on reg parms scanned so far. */
2985 CUMULATIVE_ARGS args_so_far_v;
2986 cumulative_args_t args_so_far;
2987 /* Nonzero if a reg parm has been scanned. */
2988 int reg_parm_seen;
2989 /* Nonzero if this is an indirect function call. */
2991 /* Nonzero if we must avoid push-insns in the args for this call.
2992 If stack space is allocated for register parameters, but not by the
2993 caller, then it is preallocated in the fixed part of the stack frame.
2994 So the entire argument block must then be preallocated (i.e., we
2995 ignore PUSH_ROUNDING in that case). */
2997 int must_preallocate = !PUSH_ARGS;
2999 /* Size of the stack reserved for parameter registers. */
3000 int reg_parm_stack_space = 0;
3002 /* Address of space preallocated for stack parms
3003 (on machines that lack push insns), or 0 if space not preallocated. */
3004 rtx argblock = 0;
3006 /* Mask of ECF_ and ERF_ flags. */
3007 int flags = 0;
3008 int return_flags = 0;
3009 #ifdef REG_PARM_STACK_SPACE
3010 /* Define the boundary of the register parm stack space that needs to be
3011 saved, if any. */
3012 int low_to_save, high_to_save;
3013 rtx save_area = 0; /* Place that it is saved */
3014 #endif
3016 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3017 char *initial_stack_usage_map = stack_usage_map;
3018 char *stack_usage_map_buf = NULL;
3020 int old_stack_allocated;
3022 /* State variables to track stack modifications. */
3023 rtx old_stack_level = 0;
3024 int old_stack_arg_under_construction = 0;
3025 int old_pending_adj = 0;
3026 int old_inhibit_defer_pop = inhibit_defer_pop;
3028 /* Some stack pointer alterations we make are performed via
3029 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
3030 which we then also need to save/restore along the way. */
3031 int old_stack_pointer_delta = 0;
3033 rtx call_fusage;
3034 tree addr = CALL_EXPR_FN (exp);
3035 int i;
3036 /* The alignment of the stack, in bits. */
3037 unsigned HOST_WIDE_INT preferred_stack_boundary;
3038 /* The alignment of the stack, in bytes. */
3039 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
3040 /* The static chain value to use for this call. */
3041 rtx static_chain_value;
3042 /* See if this is "nothrow" function call. */
3043 if (TREE_NOTHROW (exp))
3044 flags |= ECF_NOTHROW;
3046 /* See if we can find a DECL-node for the actual function, and get the
3047 function attributes (flags) from the function decl or type node. */
3048 fndecl = get_callee_fndecl (exp);
3049 if (fndecl)
3051 fntype = TREE_TYPE (fndecl);
3052 flags |= flags_from_decl_or_type (fndecl);
3053 return_flags |= decl_return_flags (fndecl);
3055 else
3057 fntype = TREE_TYPE (TREE_TYPE (addr));
3058 flags |= flags_from_decl_or_type (fntype);
3059 if (CALL_EXPR_BY_DESCRIPTOR (exp))
3060 flags |= ECF_BY_DESCRIPTOR;
3062 rettype = TREE_TYPE (exp);
3064 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
3066 /* Warn if this value is an aggregate type,
3067 regardless of which calling convention we are using for it. */
3068 if (AGGREGATE_TYPE_P (rettype))
3069 warning (OPT_Waggregate_return, "function call has aggregate value");
3071 /* If the result of a non looping pure or const function call is
3072 ignored (or void), and none of its arguments are volatile, we can
3073 avoid expanding the call and just evaluate the arguments for
3074 side-effects. */
3075 if ((flags & (ECF_CONST | ECF_PURE))
3076 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
3077 && (ignore || target == const0_rtx
3078 || TYPE_MODE (rettype) == VOIDmode))
3080 bool volatilep = false;
3081 tree arg;
3082 call_expr_arg_iterator iter;
3084 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3085 if (TREE_THIS_VOLATILE (arg))
3087 volatilep = true;
3088 break;
3091 if (! volatilep)
3093 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3094 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
3095 return const0_rtx;
3099 #ifdef REG_PARM_STACK_SPACE
3100 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
3101 #endif
3103 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3104 && reg_parm_stack_space > 0 && PUSH_ARGS)
3105 must_preallocate = 1;
3107 /* Set up a place to return a structure. */
3109 /* Cater to broken compilers. */
3110 if (aggregate_value_p (exp, fntype))
3112 /* This call returns a big structure. */
3113 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3115 #ifdef PCC_STATIC_STRUCT_RETURN
3117 pcc_struct_value = 1;
3119 #else /* not PCC_STATIC_STRUCT_RETURN */
3121 struct_value_size = int_size_in_bytes (rettype);
3123 /* Even if it is semantically safe to use the target as the return
3124 slot, it may be not sufficiently aligned for the return type. */
3125 if (CALL_EXPR_RETURN_SLOT_OPT (exp)
3126 && target
3127 && MEM_P (target)
3128 && !(MEM_ALIGN (target) < TYPE_ALIGN (rettype)
3129 && SLOW_UNALIGNED_ACCESS (TYPE_MODE (rettype),
3130 MEM_ALIGN (target))))
3131 structure_value_addr = XEXP (target, 0);
3132 else
3134 /* For variable-sized objects, we must be called with a target
3135 specified. If we were to allocate space on the stack here,
3136 we would have no way of knowing when to free it. */
3137 rtx d = assign_temp (rettype, 1, 1);
3138 structure_value_addr = XEXP (d, 0);
3139 target = 0;
3142 #endif /* not PCC_STATIC_STRUCT_RETURN */
3145 /* Figure out the amount to which the stack should be aligned. */
3146 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3147 if (fndecl)
3149 struct cgraph_rtl_info *i = cgraph_node::rtl_info (fndecl);
3150 /* Without automatic stack alignment, we can't increase preferred
3151 stack boundary. With automatic stack alignment, it is
3152 unnecessary since unless we can guarantee that all callers will
3153 align the outgoing stack properly, callee has to align its
3154 stack anyway. */
3155 if (i
3156 && i->preferred_incoming_stack_boundary
3157 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
3158 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
3161 /* Operand 0 is a pointer-to-function; get the type of the function. */
3162 funtype = TREE_TYPE (addr);
3163 gcc_assert (POINTER_TYPE_P (funtype));
3164 funtype = TREE_TYPE (funtype);
3166 /* Count whether there are actual complex arguments that need to be split
3167 into their real and imaginary parts. Munge the type_arg_types
3168 appropriately here as well. */
3169 if (targetm.calls.split_complex_arg)
3171 call_expr_arg_iterator iter;
3172 tree arg;
3173 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
3175 tree type = TREE_TYPE (arg);
3176 if (type && TREE_CODE (type) == COMPLEX_TYPE
3177 && targetm.calls.split_complex_arg (type))
3178 num_complex_actuals++;
3180 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
3182 else
3183 type_arg_types = TYPE_ARG_TYPES (funtype);
3185 if (flags & ECF_MAY_BE_ALLOCA)
3186 cfun->calls_alloca = 1;
3188 /* If struct_value_rtx is 0, it means pass the address
3189 as if it were an extra parameter. Put the argument expression
3190 in structure_value_addr_value. */
3191 if (structure_value_addr && struct_value == 0)
3193 /* If structure_value_addr is a REG other than
3194 virtual_outgoing_args_rtx, we can use always use it. If it
3195 is not a REG, we must always copy it into a register.
3196 If it is virtual_outgoing_args_rtx, we must copy it to another
3197 register in some cases. */
3198 rtx temp = (!REG_P (structure_value_addr)
3199 || (ACCUMULATE_OUTGOING_ARGS
3200 && stack_arg_under_construction
3201 && structure_value_addr == virtual_outgoing_args_rtx)
3202 ? copy_addr_to_reg (convert_memory_address
3203 (Pmode, structure_value_addr))
3204 : structure_value_addr);
3206 structure_value_addr_value =
3207 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
3208 structure_value_addr_parm = CALL_WITH_BOUNDS_P (exp) ? 2 : 1;
3211 /* Count the arguments and set NUM_ACTUALS. */
3212 num_actuals =
3213 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
3215 /* Compute number of named args.
3216 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
3218 if (type_arg_types != 0)
3219 n_named_args
3220 = (list_length (type_arg_types)
3221 /* Count the struct value address, if it is passed as a parm. */
3222 + structure_value_addr_parm);
3223 else
3224 /* If we know nothing, treat all args as named. */
3225 n_named_args = num_actuals;
3227 /* Start updating where the next arg would go.
3229 On some machines (such as the PA) indirect calls have a different
3230 calling convention than normal calls. The fourth argument in
3231 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
3232 or not. */
3233 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
3234 args_so_far = pack_cumulative_args (&args_so_far_v);
3236 /* Now possibly adjust the number of named args.
3237 Normally, don't include the last named arg if anonymous args follow.
3238 We do include the last named arg if
3239 targetm.calls.strict_argument_naming() returns nonzero.
3240 (If no anonymous args follow, the result of list_length is actually
3241 one too large. This is harmless.)
3243 If targetm.calls.pretend_outgoing_varargs_named() returns
3244 nonzero, and targetm.calls.strict_argument_naming() returns zero,
3245 this machine will be able to place unnamed args that were passed
3246 in registers into the stack. So treat all args as named. This
3247 allows the insns emitting for a specific argument list to be
3248 independent of the function declaration.
3250 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
3251 we do not have any reliable way to pass unnamed args in
3252 registers, so we must force them into memory. */
3254 if (type_arg_types != 0
3255 && targetm.calls.strict_argument_naming (args_so_far))
3257 else if (type_arg_types != 0
3258 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
3259 /* Don't include the last named arg. */
3260 --n_named_args;
3261 else
3262 /* Treat all args as named. */
3263 n_named_args = num_actuals;
3265 /* Make a vector to hold all the information about each arg. */
3266 args = XCNEWVEC (struct arg_data, num_actuals);
3268 /* Build up entries in the ARGS array, compute the size of the
3269 arguments into ARGS_SIZE, etc. */
3270 initialize_argument_information (num_actuals, args, &args_size,
3271 n_named_args, exp,
3272 structure_value_addr_value, fndecl, fntype,
3273 args_so_far, reg_parm_stack_space,
3274 &old_stack_level, &old_pending_adj,
3275 &must_preallocate, &flags,
3276 &try_tail_call, CALL_FROM_THUNK_P (exp));
3278 if (args_size.var)
3279 must_preallocate = 1;
3281 /* Now make final decision about preallocating stack space. */
3282 must_preallocate = finalize_must_preallocate (must_preallocate,
3283 num_actuals, args,
3284 &args_size);
3286 /* If the structure value address will reference the stack pointer, we
3287 must stabilize it. We don't need to do this if we know that we are
3288 not going to adjust the stack pointer in processing this call. */
3290 if (structure_value_addr
3291 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
3292 || reg_mentioned_p (virtual_outgoing_args_rtx,
3293 structure_value_addr))
3294 && (args_size.var
3295 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
3296 structure_value_addr = copy_to_reg (structure_value_addr);
3298 /* Tail calls can make things harder to debug, and we've traditionally
3299 pushed these optimizations into -O2. Don't try if we're already
3300 expanding a call, as that means we're an argument. Don't try if
3301 there's cleanups, as we know there's code to follow the call. */
3303 if (currently_expanding_call++ != 0
3304 || !flag_optimize_sibling_calls
3305 || args_size.var
3306 || dbg_cnt (tail_call) == false)
3307 try_tail_call = 0;
3309 /* If the user has marked the function as requiring tail-call
3310 optimization, attempt it. */
3311 if (must_tail_call)
3312 try_tail_call = 1;
3314 /* Rest of purposes for tail call optimizations to fail. */
3315 if (try_tail_call)
3316 try_tail_call = can_implement_as_sibling_call_p (exp,
3317 structure_value_addr,
3318 funtype,
3319 reg_parm_stack_space,
3320 fndecl,
3321 flags, addr, args_size);
3323 /* Check if caller and callee disagree in promotion of function
3324 return value. */
3325 if (try_tail_call)
3327 machine_mode caller_mode, caller_promoted_mode;
3328 machine_mode callee_mode, callee_promoted_mode;
3329 int caller_unsignedp, callee_unsignedp;
3330 tree caller_res = DECL_RESULT (current_function_decl);
3332 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
3333 caller_mode = DECL_MODE (caller_res);
3334 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
3335 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
3336 caller_promoted_mode
3337 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
3338 &caller_unsignedp,
3339 TREE_TYPE (current_function_decl), 1);
3340 callee_promoted_mode
3341 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
3342 &callee_unsignedp,
3343 funtype, 1);
3344 if (caller_mode != VOIDmode
3345 && (caller_promoted_mode != callee_promoted_mode
3346 || ((caller_mode != caller_promoted_mode
3347 || callee_mode != callee_promoted_mode)
3348 && (caller_unsignedp != callee_unsignedp
3349 || GET_MODE_BITSIZE (caller_mode)
3350 < GET_MODE_BITSIZE (callee_mode)))))
3352 try_tail_call = 0;
3353 maybe_complain_about_tail_call (exp,
3354 "caller and callee disagree in"
3355 " promotion of function"
3356 " return value");
3360 /* Ensure current function's preferred stack boundary is at least
3361 what we need. Stack alignment may also increase preferred stack
3362 boundary. */
3363 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
3364 crtl->preferred_stack_boundary = preferred_stack_boundary;
3365 else
3366 preferred_stack_boundary = crtl->preferred_stack_boundary;
3368 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
3370 /* We want to make two insn chains; one for a sibling call, the other
3371 for a normal call. We will select one of the two chains after
3372 initial RTL generation is complete. */
3373 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
3375 int sibcall_failure = 0;
3376 /* We want to emit any pending stack adjustments before the tail
3377 recursion "call". That way we know any adjustment after the tail
3378 recursion call can be ignored if we indeed use the tail
3379 call expansion. */
3380 saved_pending_stack_adjust save;
3381 rtx_insn *insns, *before_call, *after_args;
3382 rtx next_arg_reg;
3384 if (pass == 0)
3386 /* State variables we need to save and restore between
3387 iterations. */
3388 save_pending_stack_adjust (&save);
3390 if (pass)
3391 flags &= ~ECF_SIBCALL;
3392 else
3393 flags |= ECF_SIBCALL;
3395 /* Other state variables that we must reinitialize each time
3396 through the loop (that are not initialized by the loop itself). */
3397 argblock = 0;
3398 call_fusage = 0;
3400 /* Start a new sequence for the normal call case.
3402 From this point on, if the sibling call fails, we want to set
3403 sibcall_failure instead of continuing the loop. */
3404 start_sequence ();
3406 /* Don't let pending stack adjusts add up to too much.
3407 Also, do all pending adjustments now if there is any chance
3408 this might be a call to alloca or if we are expanding a sibling
3409 call sequence.
3410 Also do the adjustments before a throwing call, otherwise
3411 exception handling can fail; PR 19225. */
3412 if (pending_stack_adjust >= 32
3413 || (pending_stack_adjust > 0
3414 && (flags & ECF_MAY_BE_ALLOCA))
3415 || (pending_stack_adjust > 0
3416 && flag_exceptions && !(flags & ECF_NOTHROW))
3417 || pass == 0)
3418 do_pending_stack_adjust ();
3420 /* Precompute any arguments as needed. */
3421 if (pass)
3422 precompute_arguments (num_actuals, args);
3424 /* Now we are about to start emitting insns that can be deleted
3425 if a libcall is deleted. */
3426 if (pass && (flags & ECF_MALLOC))
3427 start_sequence ();
3429 if (pass == 0
3430 && crtl->stack_protect_guard
3431 && targetm.stack_protect_runtime_enabled_p ())
3432 stack_protect_epilogue ();
3434 adjusted_args_size = args_size;
3435 /* Compute the actual size of the argument block required. The variable
3436 and constant sizes must be combined, the size may have to be rounded,
3437 and there may be a minimum required size. When generating a sibcall
3438 pattern, do not round up, since we'll be re-using whatever space our
3439 caller provided. */
3440 unadjusted_args_size
3441 = compute_argument_block_size (reg_parm_stack_space,
3442 &adjusted_args_size,
3443 fndecl, fntype,
3444 (pass == 0 ? 0
3445 : preferred_stack_boundary));
3447 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3449 /* The argument block when performing a sibling call is the
3450 incoming argument block. */
3451 if (pass == 0)
3453 argblock = crtl->args.internal_arg_pointer;
3454 if (STACK_GROWS_DOWNWARD)
3455 argblock
3456 = plus_constant (Pmode, argblock, crtl->args.pretend_args_size);
3457 else
3458 argblock
3459 = plus_constant (Pmode, argblock, -crtl->args.pretend_args_size);
3461 stored_args_map = sbitmap_alloc (args_size.constant);
3462 bitmap_clear (stored_args_map);
3465 /* If we have no actual push instructions, or shouldn't use them,
3466 make space for all args right now. */
3467 else if (adjusted_args_size.var != 0)
3469 if (old_stack_level == 0)
3471 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3472 old_stack_pointer_delta = stack_pointer_delta;
3473 old_pending_adj = pending_stack_adjust;
3474 pending_stack_adjust = 0;
3475 /* stack_arg_under_construction says whether a stack arg is
3476 being constructed at the old stack level. Pushing the stack
3477 gets a clean outgoing argument block. */
3478 old_stack_arg_under_construction = stack_arg_under_construction;
3479 stack_arg_under_construction = 0;
3481 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
3482 if (flag_stack_usage_info)
3483 current_function_has_unbounded_dynamic_stack_size = 1;
3485 else
3487 /* Note that we must go through the motions of allocating an argument
3488 block even if the size is zero because we may be storing args
3489 in the area reserved for register arguments, which may be part of
3490 the stack frame. */
3492 int needed = adjusted_args_size.constant;
3494 /* Store the maximum argument space used. It will be pushed by
3495 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
3496 checking). */
3498 if (needed > crtl->outgoing_args_size)
3499 crtl->outgoing_args_size = needed;
3501 if (must_preallocate)
3503 if (ACCUMULATE_OUTGOING_ARGS)
3505 /* Since the stack pointer will never be pushed, it is
3506 possible for the evaluation of a parm to clobber
3507 something we have already written to the stack.
3508 Since most function calls on RISC machines do not use
3509 the stack, this is uncommon, but must work correctly.
3511 Therefore, we save any area of the stack that was already
3512 written and that we are using. Here we set up to do this
3513 by making a new stack usage map from the old one. The
3514 actual save will be done by store_one_arg.
3516 Another approach might be to try to reorder the argument
3517 evaluations to avoid this conflicting stack usage. */
3519 /* Since we will be writing into the entire argument area,
3520 the map must be allocated for its entire size, not just
3521 the part that is the responsibility of the caller. */
3522 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3523 needed += reg_parm_stack_space;
3525 if (ARGS_GROW_DOWNWARD)
3526 highest_outgoing_arg_in_use
3527 = MAX (initial_highest_arg_in_use, needed + 1);
3528 else
3529 highest_outgoing_arg_in_use
3530 = MAX (initial_highest_arg_in_use, needed);
3532 free (stack_usage_map_buf);
3533 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3534 stack_usage_map = stack_usage_map_buf;
3536 if (initial_highest_arg_in_use)
3537 memcpy (stack_usage_map, initial_stack_usage_map,
3538 initial_highest_arg_in_use);
3540 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3541 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3542 (highest_outgoing_arg_in_use
3543 - initial_highest_arg_in_use));
3544 needed = 0;
3546 /* The address of the outgoing argument list must not be
3547 copied to a register here, because argblock would be left
3548 pointing to the wrong place after the call to
3549 allocate_dynamic_stack_space below. */
3551 argblock = virtual_outgoing_args_rtx;
3553 else
3555 if (inhibit_defer_pop == 0)
3557 /* Try to reuse some or all of the pending_stack_adjust
3558 to get this space. */
3559 needed
3560 = (combine_pending_stack_adjustment_and_call
3561 (unadjusted_args_size,
3562 &adjusted_args_size,
3563 preferred_unit_stack_boundary));
3565 /* combine_pending_stack_adjustment_and_call computes
3566 an adjustment before the arguments are allocated.
3567 Account for them and see whether or not the stack
3568 needs to go up or down. */
3569 needed = unadjusted_args_size - needed;
3571 if (needed < 0)
3573 /* We're releasing stack space. */
3574 /* ??? We can avoid any adjustment at all if we're
3575 already aligned. FIXME. */
3576 pending_stack_adjust = -needed;
3577 do_pending_stack_adjust ();
3578 needed = 0;
3580 else
3581 /* We need to allocate space. We'll do that in
3582 push_block below. */
3583 pending_stack_adjust = 0;
3586 /* Special case this because overhead of `push_block' in
3587 this case is non-trivial. */
3588 if (needed == 0)
3589 argblock = virtual_outgoing_args_rtx;
3590 else
3592 argblock = push_block (GEN_INT (needed), 0, 0);
3593 if (ARGS_GROW_DOWNWARD)
3594 argblock = plus_constant (Pmode, argblock, needed);
3597 /* We only really need to call `copy_to_reg' in the case
3598 where push insns are going to be used to pass ARGBLOCK
3599 to a function call in ARGS. In that case, the stack
3600 pointer changes value from the allocation point to the
3601 call point, and hence the value of
3602 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
3603 as well always do it. */
3604 argblock = copy_to_reg (argblock);
3609 if (ACCUMULATE_OUTGOING_ARGS)
3611 /* The save/restore code in store_one_arg handles all
3612 cases except one: a constructor call (including a C
3613 function returning a BLKmode struct) to initialize
3614 an argument. */
3615 if (stack_arg_under_construction)
3617 rtx push_size
3618 = GEN_INT (adjusted_args_size.constant
3619 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
3620 : TREE_TYPE (fndecl))) ? 0
3621 : reg_parm_stack_space));
3622 if (old_stack_level == 0)
3624 emit_stack_save (SAVE_BLOCK, &old_stack_level);
3625 old_stack_pointer_delta = stack_pointer_delta;
3626 old_pending_adj = pending_stack_adjust;
3627 pending_stack_adjust = 0;
3628 /* stack_arg_under_construction says whether a stack
3629 arg is being constructed at the old stack level.
3630 Pushing the stack gets a clean outgoing argument
3631 block. */
3632 old_stack_arg_under_construction
3633 = stack_arg_under_construction;
3634 stack_arg_under_construction = 0;
3635 /* Make a new map for the new argument list. */
3636 free (stack_usage_map_buf);
3637 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
3638 stack_usage_map = stack_usage_map_buf;
3639 highest_outgoing_arg_in_use = 0;
3641 /* We can pass TRUE as the 4th argument because we just
3642 saved the stack pointer and will restore it right after
3643 the call. */
3644 allocate_dynamic_stack_space (push_size, 0,
3645 BIGGEST_ALIGNMENT, true);
3648 /* If argument evaluation might modify the stack pointer,
3649 copy the address of the argument list to a register. */
3650 for (i = 0; i < num_actuals; i++)
3651 if (args[i].pass_on_stack)
3653 argblock = copy_addr_to_reg (argblock);
3654 break;
3658 compute_argument_addresses (args, argblock, num_actuals);
3660 /* Stack is properly aligned, pops can't safely be deferred during
3661 the evaluation of the arguments. */
3662 NO_DEFER_POP;
3664 /* Precompute all register parameters. It isn't safe to compute
3665 anything once we have started filling any specific hard regs.
3666 TLS symbols sometimes need a call to resolve. Precompute
3667 register parameters before any stack pointer manipulation
3668 to avoid unaligned stack in the called function. */
3669 precompute_register_parameters (num_actuals, args, &reg_parm_seen);
3671 OK_DEFER_POP;
3673 /* Perform stack alignment before the first push (the last arg). */
3674 if (argblock == 0
3675 && adjusted_args_size.constant > reg_parm_stack_space
3676 && adjusted_args_size.constant != unadjusted_args_size)
3678 /* When the stack adjustment is pending, we get better code
3679 by combining the adjustments. */
3680 if (pending_stack_adjust
3681 && ! inhibit_defer_pop)
3683 pending_stack_adjust
3684 = (combine_pending_stack_adjustment_and_call
3685 (unadjusted_args_size,
3686 &adjusted_args_size,
3687 preferred_unit_stack_boundary));
3688 do_pending_stack_adjust ();
3690 else if (argblock == 0)
3691 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3692 - unadjusted_args_size));
3694 /* Now that the stack is properly aligned, pops can't safely
3695 be deferred during the evaluation of the arguments. */
3696 NO_DEFER_POP;
3698 /* Record the maximum pushed stack space size. We need to delay
3699 doing it this far to take into account the optimization done
3700 by combine_pending_stack_adjustment_and_call. */
3701 if (flag_stack_usage_info
3702 && !ACCUMULATE_OUTGOING_ARGS
3703 && pass
3704 && adjusted_args_size.var == 0)
3706 int pushed = adjusted_args_size.constant + pending_stack_adjust;
3707 if (pushed > current_function_pushed_stack_size)
3708 current_function_pushed_stack_size = pushed;
3711 funexp = rtx_for_function_call (fndecl, addr);
3713 if (CALL_EXPR_STATIC_CHAIN (exp))
3714 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
3715 else
3716 static_chain_value = 0;
3718 #ifdef REG_PARM_STACK_SPACE
3719 /* Save the fixed argument area if it's part of the caller's frame and
3720 is clobbered by argument setup for this call. */
3721 if (ACCUMULATE_OUTGOING_ARGS && pass)
3722 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3723 &low_to_save, &high_to_save);
3724 #endif
3726 /* Now store (and compute if necessary) all non-register parms.
3727 These come before register parms, since they can require block-moves,
3728 which could clobber the registers used for register parms.
3729 Parms which have partial registers are not stored here,
3730 but we do preallocate space here if they want that. */
3732 for (i = 0; i < num_actuals; i++)
3734 /* Delay bounds until all other args are stored. */
3735 if (POINTER_BOUNDS_P (args[i].tree_value))
3736 continue;
3737 else if (args[i].reg == 0 || args[i].pass_on_stack)
3739 rtx_insn *before_arg = get_last_insn ();
3741 /* We don't allow passing huge (> 2^30 B) arguments
3742 by value. It would cause an overflow later on. */
3743 if (adjusted_args_size.constant
3744 >= (1 << (HOST_BITS_PER_INT - 2)))
3746 sorry ("passing too large argument on stack");
3747 continue;
3750 if (store_one_arg (&args[i], argblock, flags,
3751 adjusted_args_size.var != 0,
3752 reg_parm_stack_space)
3753 || (pass == 0
3754 && check_sibcall_argument_overlap (before_arg,
3755 &args[i], 1)))
3756 sibcall_failure = 1;
3759 if (args[i].stack)
3760 call_fusage
3761 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3762 gen_rtx_USE (VOIDmode, args[i].stack),
3763 call_fusage);
3766 /* If we have a parm that is passed in registers but not in memory
3767 and whose alignment does not permit a direct copy into registers,
3768 make a group of pseudos that correspond to each register that we
3769 will later fill. */
3770 if (STRICT_ALIGNMENT)
3771 store_unaligned_arguments_into_pseudos (args, num_actuals);
3773 /* Now store any partially-in-registers parm.
3774 This is the last place a block-move can happen. */
3775 if (reg_parm_seen)
3776 for (i = 0; i < num_actuals; i++)
3777 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3779 rtx_insn *before_arg = get_last_insn ();
3781 /* On targets with weird calling conventions (e.g. PA) it's
3782 hard to ensure that all cases of argument overlap between
3783 stack and registers work. Play it safe and bail out. */
3784 if (ARGS_GROW_DOWNWARD && !STACK_GROWS_DOWNWARD)
3786 sibcall_failure = 1;
3787 break;
3790 if (store_one_arg (&args[i], argblock, flags,
3791 adjusted_args_size.var != 0,
3792 reg_parm_stack_space)
3793 || (pass == 0
3794 && check_sibcall_argument_overlap (before_arg,
3795 &args[i], 1)))
3796 sibcall_failure = 1;
3799 bool any_regs = false;
3800 for (i = 0; i < num_actuals; i++)
3801 if (args[i].reg != NULL_RTX)
3803 any_regs = true;
3804 targetm.calls.call_args (args[i].reg, funtype);
3806 if (!any_regs)
3807 targetm.calls.call_args (pc_rtx, funtype);
3809 /* Figure out the register where the value, if any, will come back. */
3810 valreg = 0;
3811 valbnd = 0;
3812 if (TYPE_MODE (rettype) != VOIDmode
3813 && ! structure_value_addr)
3815 if (pcc_struct_value)
3817 valreg = hard_function_value (build_pointer_type (rettype),
3818 fndecl, NULL, (pass == 0));
3819 if (CALL_WITH_BOUNDS_P (exp))
3820 valbnd = targetm.calls.
3821 chkp_function_value_bounds (build_pointer_type (rettype),
3822 fndecl, (pass == 0));
3824 else
3826 valreg = hard_function_value (rettype, fndecl, fntype,
3827 (pass == 0));
3828 if (CALL_WITH_BOUNDS_P (exp))
3829 valbnd = targetm.calls.chkp_function_value_bounds (rettype,
3830 fndecl,
3831 (pass == 0));
3834 /* If VALREG is a PARALLEL whose first member has a zero
3835 offset, use that. This is for targets such as m68k that
3836 return the same value in multiple places. */
3837 if (GET_CODE (valreg) == PARALLEL)
3839 rtx elem = XVECEXP (valreg, 0, 0);
3840 rtx where = XEXP (elem, 0);
3841 rtx offset = XEXP (elem, 1);
3842 if (offset == const0_rtx
3843 && GET_MODE (where) == GET_MODE (valreg))
3844 valreg = where;
3848 /* Store all bounds not passed in registers. */
3849 for (i = 0; i < num_actuals; i++)
3851 if (POINTER_BOUNDS_P (args[i].tree_value)
3852 && !args[i].reg)
3853 store_bounds (&args[i],
3854 args[i].pointer_arg == -1
3855 ? NULL
3856 : &args[args[i].pointer_arg]);
3859 /* If register arguments require space on the stack and stack space
3860 was not preallocated, allocate stack space here for arguments
3861 passed in registers. */
3862 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3863 && !ACCUMULATE_OUTGOING_ARGS
3864 && must_preallocate == 0 && reg_parm_stack_space > 0)
3865 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3867 /* Pass the function the address in which to return a
3868 structure value. */
3869 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3871 structure_value_addr
3872 = convert_memory_address (Pmode, structure_value_addr);
3873 emit_move_insn (struct_value,
3874 force_reg (Pmode,
3875 force_operand (structure_value_addr,
3876 NULL_RTX)));
3878 if (REG_P (struct_value))
3879 use_reg (&call_fusage, struct_value);
3882 after_args = get_last_insn ();
3883 funexp = prepare_call_address (fndecl ? fndecl : fntype, funexp,
3884 static_chain_value, &call_fusage,
3885 reg_parm_seen, flags);
3887 load_register_parameters (args, num_actuals, &call_fusage, flags,
3888 pass == 0, &sibcall_failure);
3890 /* Save a pointer to the last insn before the call, so that we can
3891 later safely search backwards to find the CALL_INSN. */
3892 before_call = get_last_insn ();
3894 /* Set up next argument register. For sibling calls on machines
3895 with register windows this should be the incoming register. */
3896 if (pass == 0)
3897 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3898 VOIDmode,
3899 void_type_node,
3900 true);
3901 else
3902 next_arg_reg = targetm.calls.function_arg (args_so_far,
3903 VOIDmode, void_type_node,
3904 true);
3906 if (pass == 1 && (return_flags & ERF_RETURNS_ARG))
3908 int arg_nr = return_flags & ERF_RETURN_ARG_MASK;
3909 arg_nr = num_actuals - arg_nr - 1;
3910 if (arg_nr >= 0
3911 && arg_nr < num_actuals
3912 && args[arg_nr].reg
3913 && valreg
3914 && REG_P (valreg)
3915 && GET_MODE (args[arg_nr].reg) == GET_MODE (valreg))
3916 call_fusage
3917 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[arg_nr].tree_value)),
3918 gen_rtx_SET (valreg, args[arg_nr].reg),
3919 call_fusage);
3921 /* All arguments and registers used for the call must be set up by
3922 now! */
3924 /* Stack must be properly aligned now. */
3925 gcc_assert (!pass
3926 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3928 /* Generate the actual call instruction. */
3929 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3930 adjusted_args_size.constant, struct_value_size,
3931 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3932 flags, args_so_far);
3934 if (flag_ipa_ra)
3936 rtx_call_insn *last;
3937 rtx datum = NULL_RTX;
3938 if (fndecl != NULL_TREE)
3940 datum = XEXP (DECL_RTL (fndecl), 0);
3941 gcc_assert (datum != NULL_RTX
3942 && GET_CODE (datum) == SYMBOL_REF);
3944 last = last_call_insn ();
3945 add_reg_note (last, REG_CALL_DECL, datum);
3948 /* If the call setup or the call itself overlaps with anything
3949 of the argument setup we probably clobbered our call address.
3950 In that case we can't do sibcalls. */
3951 if (pass == 0
3952 && check_sibcall_argument_overlap (after_args, 0, 0))
3953 sibcall_failure = 1;
3955 /* If a non-BLKmode value is returned at the most significant end
3956 of a register, shift the register right by the appropriate amount
3957 and update VALREG accordingly. BLKmode values are handled by the
3958 group load/store machinery below. */
3959 if (!structure_value_addr
3960 && !pcc_struct_value
3961 && TYPE_MODE (rettype) != VOIDmode
3962 && TYPE_MODE (rettype) != BLKmode
3963 && REG_P (valreg)
3964 && targetm.calls.return_in_msb (rettype))
3966 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3967 sibcall_failure = 1;
3968 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3971 if (pass && (flags & ECF_MALLOC))
3973 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3974 rtx_insn *last, *insns;
3976 /* The return value from a malloc-like function is a pointer. */
3977 if (TREE_CODE (rettype) == POINTER_TYPE)
3978 mark_reg_pointer (temp, MALLOC_ABI_ALIGNMENT);
3980 emit_move_insn (temp, valreg);
3982 /* The return value from a malloc-like function can not alias
3983 anything else. */
3984 last = get_last_insn ();
3985 add_reg_note (last, REG_NOALIAS, temp);
3987 /* Write out the sequence. */
3988 insns = get_insns ();
3989 end_sequence ();
3990 emit_insn (insns);
3991 valreg = temp;
3994 /* For calls to `setjmp', etc., inform
3995 function.c:setjmp_warnings that it should complain if
3996 nonvolatile values are live. For functions that cannot
3997 return, inform flow that control does not fall through. */
3999 if ((flags & ECF_NORETURN) || pass == 0)
4001 /* The barrier must be emitted
4002 immediately after the CALL_INSN. Some ports emit more
4003 than just a CALL_INSN above, so we must search for it here. */
4005 rtx_insn *last = get_last_insn ();
4006 while (!CALL_P (last))
4008 last = PREV_INSN (last);
4009 /* There was no CALL_INSN? */
4010 gcc_assert (last != before_call);
4013 emit_barrier_after (last);
4015 /* Stack adjustments after a noreturn call are dead code.
4016 However when NO_DEFER_POP is in effect, we must preserve
4017 stack_pointer_delta. */
4018 if (inhibit_defer_pop == 0)
4020 stack_pointer_delta = old_stack_allocated;
4021 pending_stack_adjust = 0;
4025 /* If value type not void, return an rtx for the value. */
4027 if (TYPE_MODE (rettype) == VOIDmode
4028 || ignore)
4029 target = const0_rtx;
4030 else if (structure_value_addr)
4032 if (target == 0 || !MEM_P (target))
4034 target
4035 = gen_rtx_MEM (TYPE_MODE (rettype),
4036 memory_address (TYPE_MODE (rettype),
4037 structure_value_addr));
4038 set_mem_attributes (target, rettype, 1);
4041 else if (pcc_struct_value)
4043 /* This is the special C++ case where we need to
4044 know what the true target was. We take care to
4045 never use this value more than once in one expression. */
4046 target = gen_rtx_MEM (TYPE_MODE (rettype),
4047 copy_to_reg (valreg));
4048 set_mem_attributes (target, rettype, 1);
4050 /* Handle calls that return values in multiple non-contiguous locations.
4051 The Irix 6 ABI has examples of this. */
4052 else if (GET_CODE (valreg) == PARALLEL)
4054 if (target == 0)
4055 target = emit_group_move_into_temps (valreg);
4056 else if (rtx_equal_p (target, valreg))
4058 else if (GET_CODE (target) == PARALLEL)
4059 /* Handle the result of a emit_group_move_into_temps
4060 call in the previous pass. */
4061 emit_group_move (target, valreg);
4062 else
4063 emit_group_store (target, valreg, rettype,
4064 int_size_in_bytes (rettype));
4066 else if (target
4067 && GET_MODE (target) == TYPE_MODE (rettype)
4068 && GET_MODE (target) == GET_MODE (valreg))
4070 bool may_overlap = false;
4072 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
4073 reg to a plain register. */
4074 if (!REG_P (target) || HARD_REGISTER_P (target))
4075 valreg = avoid_likely_spilled_reg (valreg);
4077 /* If TARGET is a MEM in the argument area, and we have
4078 saved part of the argument area, then we can't store
4079 directly into TARGET as it may get overwritten when we
4080 restore the argument save area below. Don't work too
4081 hard though and simply force TARGET to a register if it
4082 is a MEM; the optimizer is quite likely to sort it out. */
4083 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
4084 for (i = 0; i < num_actuals; i++)
4085 if (args[i].save_area)
4087 may_overlap = true;
4088 break;
4091 if (may_overlap)
4092 target = copy_to_reg (valreg);
4093 else
4095 /* TARGET and VALREG cannot be equal at this point
4096 because the latter would not have
4097 REG_FUNCTION_VALUE_P true, while the former would if
4098 it were referring to the same register.
4100 If they refer to the same register, this move will be
4101 a no-op, except when function inlining is being
4102 done. */
4103 emit_move_insn (target, valreg);
4105 /* If we are setting a MEM, this code must be executed.
4106 Since it is emitted after the call insn, sibcall
4107 optimization cannot be performed in that case. */
4108 if (MEM_P (target))
4109 sibcall_failure = 1;
4112 else
4113 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
4115 /* If we promoted this return value, make the proper SUBREG.
4116 TARGET might be const0_rtx here, so be careful. */
4117 if (REG_P (target)
4118 && TYPE_MODE (rettype) != BLKmode
4119 && GET_MODE (target) != TYPE_MODE (rettype))
4121 tree type = rettype;
4122 int unsignedp = TYPE_UNSIGNED (type);
4123 int offset = 0;
4124 machine_mode pmode;
4126 /* Ensure we promote as expected, and get the new unsignedness. */
4127 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
4128 funtype, 1);
4129 gcc_assert (GET_MODE (target) == pmode);
4131 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
4132 && (GET_MODE_SIZE (GET_MODE (target))
4133 > GET_MODE_SIZE (TYPE_MODE (type))))
4135 offset = GET_MODE_SIZE (GET_MODE (target))
4136 - GET_MODE_SIZE (TYPE_MODE (type));
4137 if (! BYTES_BIG_ENDIAN)
4138 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
4139 else if (! WORDS_BIG_ENDIAN)
4140 offset %= UNITS_PER_WORD;
4143 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
4144 SUBREG_PROMOTED_VAR_P (target) = 1;
4145 SUBREG_PROMOTED_SET (target, unsignedp);
4148 /* If size of args is variable or this was a constructor call for a stack
4149 argument, restore saved stack-pointer value. */
4151 if (old_stack_level)
4153 rtx_insn *prev = get_last_insn ();
4155 emit_stack_restore (SAVE_BLOCK, old_stack_level);
4156 stack_pointer_delta = old_stack_pointer_delta;
4158 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
4160 pending_stack_adjust = old_pending_adj;
4161 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
4162 stack_arg_under_construction = old_stack_arg_under_construction;
4163 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4164 stack_usage_map = initial_stack_usage_map;
4165 sibcall_failure = 1;
4167 else if (ACCUMULATE_OUTGOING_ARGS && pass)
4169 #ifdef REG_PARM_STACK_SPACE
4170 if (save_area)
4171 restore_fixed_argument_area (save_area, argblock,
4172 high_to_save, low_to_save);
4173 #endif
4175 /* If we saved any argument areas, restore them. */
4176 for (i = 0; i < num_actuals; i++)
4177 if (args[i].save_area)
4179 machine_mode save_mode = GET_MODE (args[i].save_area);
4180 rtx stack_area
4181 = gen_rtx_MEM (save_mode,
4182 memory_address (save_mode,
4183 XEXP (args[i].stack_slot, 0)));
4185 if (save_mode != BLKmode)
4186 emit_move_insn (stack_area, args[i].save_area);
4187 else
4188 emit_block_move (stack_area, args[i].save_area,
4189 GEN_INT (args[i].locate.size.constant),
4190 BLOCK_OP_CALL_PARM);
4193 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4194 stack_usage_map = initial_stack_usage_map;
4197 /* If this was alloca, record the new stack level. */
4198 if (flags & ECF_MAY_BE_ALLOCA)
4199 record_new_stack_level ();
4201 /* Free up storage we no longer need. */
4202 for (i = 0; i < num_actuals; ++i)
4203 free (args[i].aligned_regs);
4205 targetm.calls.end_call_args ();
4207 insns = get_insns ();
4208 end_sequence ();
4210 if (pass == 0)
4212 tail_call_insns = insns;
4214 /* Restore the pending stack adjustment now that we have
4215 finished generating the sibling call sequence. */
4217 restore_pending_stack_adjust (&save);
4219 /* Prepare arg structure for next iteration. */
4220 for (i = 0; i < num_actuals; i++)
4222 args[i].value = 0;
4223 args[i].aligned_regs = 0;
4224 args[i].stack = 0;
4227 sbitmap_free (stored_args_map);
4228 internal_arg_pointer_exp_state.scan_start = NULL;
4229 internal_arg_pointer_exp_state.cache.release ();
4231 else
4233 normal_call_insns = insns;
4235 /* Verify that we've deallocated all the stack we used. */
4236 gcc_assert ((flags & ECF_NORETURN)
4237 || (old_stack_allocated
4238 == stack_pointer_delta - pending_stack_adjust));
4241 /* If something prevents making this a sibling call,
4242 zero out the sequence. */
4243 if (sibcall_failure)
4244 tail_call_insns = NULL;
4245 else
4246 break;
4249 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
4250 arguments too, as argument area is now clobbered by the call. */
4251 if (tail_call_insns)
4253 emit_insn (tail_call_insns);
4254 crtl->tail_call_emit = true;
4256 else
4258 emit_insn (normal_call_insns);
4259 if (try_tail_call)
4260 /* Ideally we'd emit a message for all of the ways that it could
4261 have failed. */
4262 maybe_complain_about_tail_call (exp, "tail call production failed");
4265 currently_expanding_call--;
4267 free (stack_usage_map_buf);
4268 free (args);
4270 /* Join result with returned bounds so caller may use them if needed. */
4271 target = chkp_join_splitted_slot (target, valbnd);
4273 return target;
4276 /* A sibling call sequence invalidates any REG_EQUIV notes made for
4277 this function's incoming arguments.
4279 At the start of RTL generation we know the only REG_EQUIV notes
4280 in the rtl chain are those for incoming arguments, so we can look
4281 for REG_EQUIV notes between the start of the function and the
4282 NOTE_INSN_FUNCTION_BEG.
4284 This is (slight) overkill. We could keep track of the highest
4285 argument we clobber and be more selective in removing notes, but it
4286 does not seem to be worth the effort. */
4288 void
4289 fixup_tail_calls (void)
4291 rtx_insn *insn;
4293 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4295 rtx note;
4297 /* There are never REG_EQUIV notes for the incoming arguments
4298 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
4299 if (NOTE_P (insn)
4300 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
4301 break;
4303 note = find_reg_note (insn, REG_EQUIV, 0);
4304 if (note)
4305 remove_note (insn, note);
4306 note = find_reg_note (insn, REG_EQUIV, 0);
4307 gcc_assert (!note);
4311 /* Traverse a list of TYPES and expand all complex types into their
4312 components. */
4313 static tree
4314 split_complex_types (tree types)
4316 tree p;
4318 /* Before allocating memory, check for the common case of no complex. */
4319 for (p = types; p; p = TREE_CHAIN (p))
4321 tree type = TREE_VALUE (p);
4322 if (TREE_CODE (type) == COMPLEX_TYPE
4323 && targetm.calls.split_complex_arg (type))
4324 goto found;
4326 return types;
4328 found:
4329 types = copy_list (types);
4331 for (p = types; p; p = TREE_CHAIN (p))
4333 tree complex_type = TREE_VALUE (p);
4335 if (TREE_CODE (complex_type) == COMPLEX_TYPE
4336 && targetm.calls.split_complex_arg (complex_type))
4338 tree next, imag;
4340 /* Rewrite complex type with component type. */
4341 TREE_VALUE (p) = TREE_TYPE (complex_type);
4342 next = TREE_CHAIN (p);
4344 /* Add another component type for the imaginary part. */
4345 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
4346 TREE_CHAIN (p) = imag;
4347 TREE_CHAIN (imag) = next;
4349 /* Skip the newly created node. */
4350 p = TREE_CHAIN (p);
4354 return types;
4357 /* Output a library call to function FUN (a SYMBOL_REF rtx).
4358 The RETVAL parameter specifies whether return value needs to be saved, other
4359 parameters are documented in the emit_library_call function below. */
4361 static rtx
4362 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
4363 enum libcall_type fn_type,
4364 machine_mode outmode, int nargs, va_list p)
4366 /* Total size in bytes of all the stack-parms scanned so far. */
4367 struct args_size args_size;
4368 /* Size of arguments before any adjustments (such as rounding). */
4369 struct args_size original_args_size;
4370 int argnum;
4371 rtx fun;
4372 /* Todo, choose the correct decl type of orgfun. Sadly this information
4373 isn't present here, so we default to native calling abi here. */
4374 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4375 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
4376 int count;
4377 rtx argblock = 0;
4378 CUMULATIVE_ARGS args_so_far_v;
4379 cumulative_args_t args_so_far;
4380 struct arg
4382 rtx value;
4383 machine_mode mode;
4384 rtx reg;
4385 int partial;
4386 struct locate_and_pad_arg_data locate;
4387 rtx save_area;
4389 struct arg *argvec;
4390 int old_inhibit_defer_pop = inhibit_defer_pop;
4391 rtx call_fusage = 0;
4392 rtx mem_value = 0;
4393 rtx valreg;
4394 int pcc_struct_value = 0;
4395 int struct_value_size = 0;
4396 int flags;
4397 int reg_parm_stack_space = 0;
4398 int needed;
4399 rtx_insn *before_call;
4400 bool have_push_fusage;
4401 tree tfom; /* type_for_mode (outmode, 0) */
4403 #ifdef REG_PARM_STACK_SPACE
4404 /* Define the boundary of the register parm stack space that needs to be
4405 save, if any. */
4406 int low_to_save = 0, high_to_save = 0;
4407 rtx save_area = 0; /* Place that it is saved. */
4408 #endif
4410 /* Size of the stack reserved for parameter registers. */
4411 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
4412 char *initial_stack_usage_map = stack_usage_map;
4413 char *stack_usage_map_buf = NULL;
4415 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
4417 #ifdef REG_PARM_STACK_SPACE
4418 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
4419 #endif
4421 /* By default, library functions cannot throw. */
4422 flags = ECF_NOTHROW;
4424 switch (fn_type)
4426 case LCT_NORMAL:
4427 break;
4428 case LCT_CONST:
4429 flags |= ECF_CONST;
4430 break;
4431 case LCT_PURE:
4432 flags |= ECF_PURE;
4433 break;
4434 case LCT_NORETURN:
4435 flags |= ECF_NORETURN;
4436 break;
4437 case LCT_THROW:
4438 flags &= ~ECF_NOTHROW;
4439 break;
4440 case LCT_RETURNS_TWICE:
4441 flags = ECF_RETURNS_TWICE;
4442 break;
4444 fun = orgfun;
4446 /* Ensure current function's preferred stack boundary is at least
4447 what we need. */
4448 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
4449 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4451 /* If this kind of value comes back in memory,
4452 decide where in memory it should come back. */
4453 if (outmode != VOIDmode)
4455 tfom = lang_hooks.types.type_for_mode (outmode, 0);
4456 if (aggregate_value_p (tfom, 0))
4458 #ifdef PCC_STATIC_STRUCT_RETURN
4459 rtx pointer_reg
4460 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
4461 mem_value = gen_rtx_MEM (outmode, pointer_reg);
4462 pcc_struct_value = 1;
4463 if (value == 0)
4464 value = gen_reg_rtx (outmode);
4465 #else /* not PCC_STATIC_STRUCT_RETURN */
4466 struct_value_size = GET_MODE_SIZE (outmode);
4467 if (value != 0 && MEM_P (value))
4468 mem_value = value;
4469 else
4470 mem_value = assign_temp (tfom, 1, 1);
4471 #endif
4472 /* This call returns a big structure. */
4473 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
4476 else
4477 tfom = void_type_node;
4479 /* ??? Unfinished: must pass the memory address as an argument. */
4481 /* Copy all the libcall-arguments out of the varargs data
4482 and into a vector ARGVEC.
4484 Compute how to pass each argument. We only support a very small subset
4485 of the full argument passing conventions to limit complexity here since
4486 library functions shouldn't have many args. */
4488 argvec = XALLOCAVEC (struct arg, nargs + 1);
4489 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
4491 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
4492 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
4493 #else
4494 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
4495 #endif
4496 args_so_far = pack_cumulative_args (&args_so_far_v);
4498 args_size.constant = 0;
4499 args_size.var = 0;
4501 count = 0;
4503 push_temp_slots ();
4505 /* If there's a structure value address to be passed,
4506 either pass it in the special place, or pass it as an extra argument. */
4507 if (mem_value && struct_value == 0 && ! pcc_struct_value)
4509 rtx addr = XEXP (mem_value, 0);
4511 nargs++;
4513 /* Make sure it is a reasonable operand for a move or push insn. */
4514 if (!REG_P (addr) && !MEM_P (addr)
4515 && !(CONSTANT_P (addr)
4516 && targetm.legitimate_constant_p (Pmode, addr)))
4517 addr = force_operand (addr, NULL_RTX);
4519 argvec[count].value = addr;
4520 argvec[count].mode = Pmode;
4521 argvec[count].partial = 0;
4523 argvec[count].reg = targetm.calls.function_arg (args_so_far,
4524 Pmode, NULL_TREE, true);
4525 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
4526 NULL_TREE, 1) == 0);
4528 locate_and_pad_parm (Pmode, NULL_TREE,
4529 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4531 #else
4532 argvec[count].reg != 0,
4533 #endif
4534 reg_parm_stack_space, 0,
4535 NULL_TREE, &args_size, &argvec[count].locate);
4537 if (argvec[count].reg == 0 || argvec[count].partial != 0
4538 || reg_parm_stack_space > 0)
4539 args_size.constant += argvec[count].locate.size.constant;
4541 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
4543 count++;
4546 for (; count < nargs; count++)
4548 rtx val = va_arg (p, rtx);
4549 machine_mode mode = (machine_mode) va_arg (p, int);
4550 int unsigned_p = 0;
4552 /* We cannot convert the arg value to the mode the library wants here;
4553 must do it earlier where we know the signedness of the arg. */
4554 gcc_assert (mode != BLKmode
4555 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
4557 /* Make sure it is a reasonable operand for a move or push insn. */
4558 if (!REG_P (val) && !MEM_P (val)
4559 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
4560 val = force_operand (val, NULL_RTX);
4562 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
4564 rtx slot;
4565 int must_copy
4566 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
4568 /* If this was a CONST function, it is now PURE since it now
4569 reads memory. */
4570 if (flags & ECF_CONST)
4572 flags &= ~ECF_CONST;
4573 flags |= ECF_PURE;
4576 if (MEM_P (val) && !must_copy)
4578 tree val_expr = MEM_EXPR (val);
4579 if (val_expr)
4580 mark_addressable (val_expr);
4581 slot = val;
4583 else
4585 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
4586 1, 1);
4587 emit_move_insn (slot, val);
4590 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4591 gen_rtx_USE (VOIDmode, slot),
4592 call_fusage);
4593 if (must_copy)
4594 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
4595 gen_rtx_CLOBBER (VOIDmode,
4596 slot),
4597 call_fusage);
4599 mode = Pmode;
4600 val = force_operand (XEXP (slot, 0), NULL_RTX);
4603 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
4604 argvec[count].mode = mode;
4605 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
4606 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
4607 NULL_TREE, true);
4609 argvec[count].partial
4610 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
4612 if (argvec[count].reg == 0
4613 || argvec[count].partial != 0
4614 || reg_parm_stack_space > 0)
4616 locate_and_pad_parm (mode, NULL_TREE,
4617 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4619 #else
4620 argvec[count].reg != 0,
4621 #endif
4622 reg_parm_stack_space, argvec[count].partial,
4623 NULL_TREE, &args_size, &argvec[count].locate);
4624 args_size.constant += argvec[count].locate.size.constant;
4625 gcc_assert (!argvec[count].locate.size.var);
4627 #ifdef BLOCK_REG_PADDING
4628 else
4629 /* The argument is passed entirely in registers. See at which
4630 end it should be padded. */
4631 argvec[count].locate.where_pad =
4632 BLOCK_REG_PADDING (mode, NULL_TREE,
4633 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
4634 #endif
4636 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
4639 /* If this machine requires an external definition for library
4640 functions, write one out. */
4641 assemble_external_libcall (fun);
4643 original_args_size = args_size;
4644 args_size.constant = (((args_size.constant
4645 + stack_pointer_delta
4646 + STACK_BYTES - 1)
4647 / STACK_BYTES
4648 * STACK_BYTES)
4649 - stack_pointer_delta);
4651 args_size.constant = MAX (args_size.constant,
4652 reg_parm_stack_space);
4654 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4655 args_size.constant -= reg_parm_stack_space;
4657 if (args_size.constant > crtl->outgoing_args_size)
4658 crtl->outgoing_args_size = args_size.constant;
4660 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
4662 int pushed = args_size.constant + pending_stack_adjust;
4663 if (pushed > current_function_pushed_stack_size)
4664 current_function_pushed_stack_size = pushed;
4667 if (ACCUMULATE_OUTGOING_ARGS)
4669 /* Since the stack pointer will never be pushed, it is possible for
4670 the evaluation of a parm to clobber something we have already
4671 written to the stack. Since most function calls on RISC machines
4672 do not use the stack, this is uncommon, but must work correctly.
4674 Therefore, we save any area of the stack that was already written
4675 and that we are using. Here we set up to do this by making a new
4676 stack usage map from the old one.
4678 Another approach might be to try to reorder the argument
4679 evaluations to avoid this conflicting stack usage. */
4681 needed = args_size.constant;
4683 /* Since we will be writing into the entire argument area, the
4684 map must be allocated for its entire size, not just the part that
4685 is the responsibility of the caller. */
4686 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
4687 needed += reg_parm_stack_space;
4689 if (ARGS_GROW_DOWNWARD)
4690 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
4691 needed + 1);
4692 else
4693 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use, needed);
4695 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
4696 stack_usage_map = stack_usage_map_buf;
4698 if (initial_highest_arg_in_use)
4699 memcpy (stack_usage_map, initial_stack_usage_map,
4700 initial_highest_arg_in_use);
4702 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
4703 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
4704 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
4705 needed = 0;
4707 /* We must be careful to use virtual regs before they're instantiated,
4708 and real regs afterwards. Loop optimization, for example, can create
4709 new libcalls after we've instantiated the virtual regs, and if we
4710 use virtuals anyway, they won't match the rtl patterns. */
4712 if (virtuals_instantiated)
4713 argblock = plus_constant (Pmode, stack_pointer_rtx,
4714 STACK_POINTER_OFFSET);
4715 else
4716 argblock = virtual_outgoing_args_rtx;
4718 else
4720 if (!PUSH_ARGS)
4721 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
4724 /* We push args individually in reverse order, perform stack alignment
4725 before the first push (the last arg). */
4726 if (argblock == 0)
4727 anti_adjust_stack (GEN_INT (args_size.constant
4728 - original_args_size.constant));
4730 argnum = nargs - 1;
4732 #ifdef REG_PARM_STACK_SPACE
4733 if (ACCUMULATE_OUTGOING_ARGS)
4735 /* The argument list is the property of the called routine and it
4736 may clobber it. If the fixed area has been used for previous
4737 parameters, we must save and restore it. */
4738 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
4739 &low_to_save, &high_to_save);
4741 #endif
4743 /* When expanding a normal call, args are stored in push order,
4744 which is the reverse of what we have here. */
4745 bool any_regs = false;
4746 for (int i = nargs; i-- > 0; )
4747 if (argvec[i].reg != NULL_RTX)
4749 targetm.calls.call_args (argvec[i].reg, NULL_TREE);
4750 any_regs = true;
4752 if (!any_regs)
4753 targetm.calls.call_args (pc_rtx, NULL_TREE);
4755 /* Push the args that need to be pushed. */
4757 have_push_fusage = false;
4759 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4760 are to be pushed. */
4761 for (count = 0; count < nargs; count++, argnum--)
4763 machine_mode mode = argvec[argnum].mode;
4764 rtx val = argvec[argnum].value;
4765 rtx reg = argvec[argnum].reg;
4766 int partial = argvec[argnum].partial;
4767 unsigned int parm_align = argvec[argnum].locate.boundary;
4768 int lower_bound = 0, upper_bound = 0, i;
4770 if (! (reg != 0 && partial == 0))
4772 rtx use;
4774 if (ACCUMULATE_OUTGOING_ARGS)
4776 /* If this is being stored into a pre-allocated, fixed-size,
4777 stack area, save any previous data at that location. */
4779 if (ARGS_GROW_DOWNWARD)
4781 /* stack_slot is negative, but we want to index stack_usage_map
4782 with positive values. */
4783 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
4784 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
4786 else
4788 lower_bound = argvec[argnum].locate.slot_offset.constant;
4789 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
4792 i = lower_bound;
4793 /* Don't worry about things in the fixed argument area;
4794 it has already been saved. */
4795 if (i < reg_parm_stack_space)
4796 i = reg_parm_stack_space;
4797 while (i < upper_bound && stack_usage_map[i] == 0)
4798 i++;
4800 if (i < upper_bound)
4802 /* We need to make a save area. */
4803 unsigned int size
4804 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
4805 machine_mode save_mode
4806 = mode_for_size (size, MODE_INT, 1);
4807 rtx adr
4808 = plus_constant (Pmode, argblock,
4809 argvec[argnum].locate.offset.constant);
4810 rtx stack_area
4811 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
4813 if (save_mode == BLKmode)
4815 argvec[argnum].save_area
4816 = assign_stack_temp (BLKmode,
4817 argvec[argnum].locate.size.constant
4820 emit_block_move (validize_mem
4821 (copy_rtx (argvec[argnum].save_area)),
4822 stack_area,
4823 GEN_INT (argvec[argnum].locate.size.constant),
4824 BLOCK_OP_CALL_PARM);
4826 else
4828 argvec[argnum].save_area = gen_reg_rtx (save_mode);
4830 emit_move_insn (argvec[argnum].save_area, stack_area);
4835 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
4836 partial, reg, 0, argblock,
4837 GEN_INT (argvec[argnum].locate.offset.constant),
4838 reg_parm_stack_space,
4839 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad), false);
4841 /* Now mark the segment we just used. */
4842 if (ACCUMULATE_OUTGOING_ARGS)
4843 for (i = lower_bound; i < upper_bound; i++)
4844 stack_usage_map[i] = 1;
4846 NO_DEFER_POP;
4848 /* Indicate argument access so that alias.c knows that these
4849 values are live. */
4850 if (argblock)
4851 use = plus_constant (Pmode, argblock,
4852 argvec[argnum].locate.offset.constant);
4853 else if (have_push_fusage)
4854 continue;
4855 else
4857 /* When arguments are pushed, trying to tell alias.c where
4858 exactly this argument is won't work, because the
4859 auto-increment causes confusion. So we merely indicate
4860 that we access something with a known mode somewhere on
4861 the stack. */
4862 use = gen_rtx_PLUS (Pmode, stack_pointer_rtx,
4863 gen_rtx_SCRATCH (Pmode));
4864 have_push_fusage = true;
4866 use = gen_rtx_MEM (argvec[argnum].mode, use);
4867 use = gen_rtx_USE (VOIDmode, use);
4868 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4872 argnum = nargs - 1;
4874 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4876 /* Now load any reg parms into their regs. */
4878 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4879 are to be pushed. */
4880 for (count = 0; count < nargs; count++, argnum--)
4882 machine_mode mode = argvec[argnum].mode;
4883 rtx val = argvec[argnum].value;
4884 rtx reg = argvec[argnum].reg;
4885 int partial = argvec[argnum].partial;
4886 #ifdef BLOCK_REG_PADDING
4887 int size = 0;
4888 #endif
4890 /* Handle calls that pass values in multiple non-contiguous
4891 locations. The PA64 has examples of this for library calls. */
4892 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4893 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4894 else if (reg != 0 && partial == 0)
4896 emit_move_insn (reg, val);
4897 #ifdef BLOCK_REG_PADDING
4898 size = GET_MODE_SIZE (argvec[argnum].mode);
4900 /* Copied from load_register_parameters. */
4902 /* Handle case where we have a value that needs shifting
4903 up to the msb. eg. a QImode value and we're padding
4904 upward on a BYTES_BIG_ENDIAN machine. */
4905 if (size < UNITS_PER_WORD
4906 && (argvec[argnum].locate.where_pad
4907 == (BYTES_BIG_ENDIAN ? upward : downward)))
4909 rtx x;
4910 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4912 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4913 report the whole reg as used. Strictly speaking, the
4914 call only uses SIZE bytes at the msb end, but it doesn't
4915 seem worth generating rtl to say that. */
4916 reg = gen_rtx_REG (word_mode, REGNO (reg));
4917 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4918 if (x != reg)
4919 emit_move_insn (reg, x);
4921 #endif
4924 NO_DEFER_POP;
4927 /* Any regs containing parms remain in use through the call. */
4928 for (count = 0; count < nargs; count++)
4930 rtx reg = argvec[count].reg;
4931 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4932 use_group_regs (&call_fusage, reg);
4933 else if (reg != 0)
4935 int partial = argvec[count].partial;
4936 if (partial)
4938 int nregs;
4939 gcc_assert (partial % UNITS_PER_WORD == 0);
4940 nregs = partial / UNITS_PER_WORD;
4941 use_regs (&call_fusage, REGNO (reg), nregs);
4943 else
4944 use_reg (&call_fusage, reg);
4948 /* Pass the function the address in which to return a structure value. */
4949 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4951 emit_move_insn (struct_value,
4952 force_reg (Pmode,
4953 force_operand (XEXP (mem_value, 0),
4954 NULL_RTX)));
4955 if (REG_P (struct_value))
4956 use_reg (&call_fusage, struct_value);
4959 /* Don't allow popping to be deferred, since then
4960 cse'ing of library calls could delete a call and leave the pop. */
4961 NO_DEFER_POP;
4962 valreg = (mem_value == 0 && outmode != VOIDmode
4963 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4965 /* Stack must be properly aligned now. */
4966 gcc_assert (!(stack_pointer_delta
4967 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4969 before_call = get_last_insn ();
4971 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4972 will set inhibit_defer_pop to that value. */
4973 /* The return type is needed to decide how many bytes the function pops.
4974 Signedness plays no role in that, so for simplicity, we pretend it's
4975 always signed. We also assume that the list of arguments passed has
4976 no impact, so we pretend it is unknown. */
4978 emit_call_1 (fun, NULL,
4979 get_identifier (XSTR (orgfun, 0)),
4980 build_function_type (tfom, NULL_TREE),
4981 original_args_size.constant, args_size.constant,
4982 struct_value_size,
4983 targetm.calls.function_arg (args_so_far,
4984 VOIDmode, void_type_node, true),
4985 valreg,
4986 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4988 if (flag_ipa_ra)
4990 rtx datum = orgfun;
4991 gcc_assert (GET_CODE (datum) == SYMBOL_REF);
4992 rtx_call_insn *last = last_call_insn ();
4993 add_reg_note (last, REG_CALL_DECL, datum);
4996 /* Right-shift returned value if necessary. */
4997 if (!pcc_struct_value
4998 && TYPE_MODE (tfom) != BLKmode
4999 && targetm.calls.return_in_msb (tfom))
5001 shift_return_value (TYPE_MODE (tfom), false, valreg);
5002 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
5005 targetm.calls.end_call_args ();
5007 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
5008 that it should complain if nonvolatile values are live. For
5009 functions that cannot return, inform flow that control does not
5010 fall through. */
5011 if (flags & ECF_NORETURN)
5013 /* The barrier note must be emitted
5014 immediately after the CALL_INSN. Some ports emit more than
5015 just a CALL_INSN above, so we must search for it here. */
5016 rtx_insn *last = get_last_insn ();
5017 while (!CALL_P (last))
5019 last = PREV_INSN (last);
5020 /* There was no CALL_INSN? */
5021 gcc_assert (last != before_call);
5024 emit_barrier_after (last);
5027 /* Consider that "regular" libcalls, i.e. all of them except for LCT_THROW
5028 and LCT_RETURNS_TWICE, cannot perform non-local gotos. */
5029 if (flags & ECF_NOTHROW)
5031 rtx_insn *last = get_last_insn ();
5032 while (!CALL_P (last))
5034 last = PREV_INSN (last);
5035 /* There was no CALL_INSN? */
5036 gcc_assert (last != before_call);
5039 make_reg_eh_region_note_nothrow_nononlocal (last);
5042 /* Now restore inhibit_defer_pop to its actual original value. */
5043 OK_DEFER_POP;
5045 pop_temp_slots ();
5047 /* Copy the value to the right place. */
5048 if (outmode != VOIDmode && retval)
5050 if (mem_value)
5052 if (value == 0)
5053 value = mem_value;
5054 if (value != mem_value)
5055 emit_move_insn (value, mem_value);
5057 else if (GET_CODE (valreg) == PARALLEL)
5059 if (value == 0)
5060 value = gen_reg_rtx (outmode);
5061 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
5063 else
5065 /* Convert to the proper mode if a promotion has been active. */
5066 if (GET_MODE (valreg) != outmode)
5068 int unsignedp = TYPE_UNSIGNED (tfom);
5070 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
5071 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
5072 == GET_MODE (valreg));
5073 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
5076 if (value != 0)
5077 emit_move_insn (value, valreg);
5078 else
5079 value = valreg;
5083 if (ACCUMULATE_OUTGOING_ARGS)
5085 #ifdef REG_PARM_STACK_SPACE
5086 if (save_area)
5087 restore_fixed_argument_area (save_area, argblock,
5088 high_to_save, low_to_save);
5089 #endif
5091 /* If we saved any argument areas, restore them. */
5092 for (count = 0; count < nargs; count++)
5093 if (argvec[count].save_area)
5095 machine_mode save_mode = GET_MODE (argvec[count].save_area);
5096 rtx adr = plus_constant (Pmode, argblock,
5097 argvec[count].locate.offset.constant);
5098 rtx stack_area = gen_rtx_MEM (save_mode,
5099 memory_address (save_mode, adr));
5101 if (save_mode == BLKmode)
5102 emit_block_move (stack_area,
5103 validize_mem
5104 (copy_rtx (argvec[count].save_area)),
5105 GEN_INT (argvec[count].locate.size.constant),
5106 BLOCK_OP_CALL_PARM);
5107 else
5108 emit_move_insn (stack_area, argvec[count].save_area);
5111 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
5112 stack_usage_map = initial_stack_usage_map;
5115 free (stack_usage_map_buf);
5117 return value;
5121 /* Output a library call to function FUN (a SYMBOL_REF rtx)
5122 (emitting the queue unless NO_QUEUE is nonzero),
5123 for a value of mode OUTMODE,
5124 with NARGS different arguments, passed as alternating rtx values
5125 and machine_modes to convert them to.
5127 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
5128 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
5129 other types of library calls. */
5131 void
5132 emit_library_call (rtx orgfun, enum libcall_type fn_type,
5133 machine_mode outmode, int nargs, ...)
5135 va_list p;
5137 va_start (p, nargs);
5138 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
5139 va_end (p);
5142 /* Like emit_library_call except that an extra argument, VALUE,
5143 comes second and says where to store the result.
5144 (If VALUE is zero, this function chooses a convenient way
5145 to return the value.
5147 This function returns an rtx for where the value is to be found.
5148 If VALUE is nonzero, VALUE is returned. */
5151 emit_library_call_value (rtx orgfun, rtx value,
5152 enum libcall_type fn_type,
5153 machine_mode outmode, int nargs, ...)
5155 rtx result;
5156 va_list p;
5158 va_start (p, nargs);
5159 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
5160 nargs, p);
5161 va_end (p);
5163 return result;
5167 /* Store pointer bounds argument ARG into Bounds Table entry
5168 associated with PARM. */
5169 static void
5170 store_bounds (struct arg_data *arg, struct arg_data *parm)
5172 rtx slot = NULL, ptr = NULL, addr = NULL;
5174 /* We may pass bounds not associated with any pointer. */
5175 if (!parm)
5177 gcc_assert (arg->special_slot);
5178 slot = arg->special_slot;
5179 ptr = const0_rtx;
5181 /* Find pointer associated with bounds and where it is
5182 passed. */
5183 else
5185 if (!parm->reg)
5187 gcc_assert (!arg->special_slot);
5189 addr = adjust_address (parm->stack, Pmode, arg->pointer_offset);
5191 else if (REG_P (parm->reg))
5193 gcc_assert (arg->special_slot);
5194 slot = arg->special_slot;
5196 if (MEM_P (parm->value))
5197 addr = adjust_address (parm->value, Pmode, arg->pointer_offset);
5198 else if (REG_P (parm->value))
5199 ptr = gen_rtx_SUBREG (Pmode, parm->value, arg->pointer_offset);
5200 else
5202 gcc_assert (!arg->pointer_offset);
5203 ptr = parm->value;
5206 else
5208 gcc_assert (GET_CODE (parm->reg) == PARALLEL);
5210 gcc_assert (arg->special_slot);
5211 slot = arg->special_slot;
5213 if (parm->parallel_value)
5214 ptr = chkp_get_value_with_offs (parm->parallel_value,
5215 GEN_INT (arg->pointer_offset));
5216 else
5217 gcc_unreachable ();
5221 /* Expand bounds. */
5222 if (!arg->value)
5223 arg->value = expand_normal (arg->tree_value);
5225 targetm.calls.store_bounds_for_arg (ptr, addr, arg->value, slot);
5228 /* Store a single argument for a function call
5229 into the register or memory area where it must be passed.
5230 *ARG describes the argument value and where to pass it.
5232 ARGBLOCK is the address of the stack-block for all the arguments,
5233 or 0 on a machine where arguments are pushed individually.
5235 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
5236 so must be careful about how the stack is used.
5238 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
5239 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
5240 that we need not worry about saving and restoring the stack.
5242 FNDECL is the declaration of the function we are calling.
5244 Return nonzero if this arg should cause sibcall failure,
5245 zero otherwise. */
5247 static int
5248 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
5249 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
5251 tree pval = arg->tree_value;
5252 rtx reg = 0;
5253 int partial = 0;
5254 int used = 0;
5255 int i, lower_bound = 0, upper_bound = 0;
5256 int sibcall_failure = 0;
5258 if (TREE_CODE (pval) == ERROR_MARK)
5259 return 1;
5261 /* Push a new temporary level for any temporaries we make for
5262 this argument. */
5263 push_temp_slots ();
5265 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
5267 /* If this is being stored into a pre-allocated, fixed-size, stack area,
5268 save any previous data at that location. */
5269 if (argblock && ! variable_size && arg->stack)
5271 if (ARGS_GROW_DOWNWARD)
5273 /* stack_slot is negative, but we want to index stack_usage_map
5274 with positive values. */
5275 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5276 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
5277 else
5278 upper_bound = 0;
5280 lower_bound = upper_bound - arg->locate.size.constant;
5282 else
5284 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
5285 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
5286 else
5287 lower_bound = 0;
5289 upper_bound = lower_bound + arg->locate.size.constant;
5292 i = lower_bound;
5293 /* Don't worry about things in the fixed argument area;
5294 it has already been saved. */
5295 if (i < reg_parm_stack_space)
5296 i = reg_parm_stack_space;
5297 while (i < upper_bound && stack_usage_map[i] == 0)
5298 i++;
5300 if (i < upper_bound)
5302 /* We need to make a save area. */
5303 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
5304 machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
5305 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
5306 rtx stack_area = gen_rtx_MEM (save_mode, adr);
5308 if (save_mode == BLKmode)
5310 arg->save_area
5311 = assign_temp (TREE_TYPE (arg->tree_value), 1, 1);
5312 preserve_temp_slots (arg->save_area);
5313 emit_block_move (validize_mem (copy_rtx (arg->save_area)),
5314 stack_area,
5315 GEN_INT (arg->locate.size.constant),
5316 BLOCK_OP_CALL_PARM);
5318 else
5320 arg->save_area = gen_reg_rtx (save_mode);
5321 emit_move_insn (arg->save_area, stack_area);
5327 /* If this isn't going to be placed on both the stack and in registers,
5328 set up the register and number of words. */
5329 if (! arg->pass_on_stack)
5331 if (flags & ECF_SIBCALL)
5332 reg = arg->tail_call_reg;
5333 else
5334 reg = arg->reg;
5335 partial = arg->partial;
5338 /* Being passed entirely in a register. We shouldn't be called in
5339 this case. */
5340 gcc_assert (reg == 0 || partial != 0);
5342 /* If this arg needs special alignment, don't load the registers
5343 here. */
5344 if (arg->n_aligned_regs != 0)
5345 reg = 0;
5347 /* If this is being passed partially in a register, we can't evaluate
5348 it directly into its stack slot. Otherwise, we can. */
5349 if (arg->value == 0)
5351 /* stack_arg_under_construction is nonzero if a function argument is
5352 being evaluated directly into the outgoing argument list and
5353 expand_call must take special action to preserve the argument list
5354 if it is called recursively.
5356 For scalar function arguments stack_usage_map is sufficient to
5357 determine which stack slots must be saved and restored. Scalar
5358 arguments in general have pass_on_stack == 0.
5360 If this argument is initialized by a function which takes the
5361 address of the argument (a C++ constructor or a C function
5362 returning a BLKmode structure), then stack_usage_map is
5363 insufficient and expand_call must push the stack around the
5364 function call. Such arguments have pass_on_stack == 1.
5366 Note that it is always safe to set stack_arg_under_construction,
5367 but this generates suboptimal code if set when not needed. */
5369 if (arg->pass_on_stack)
5370 stack_arg_under_construction++;
5372 arg->value = expand_expr (pval,
5373 (partial
5374 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
5375 ? NULL_RTX : arg->stack,
5376 VOIDmode, EXPAND_STACK_PARM);
5378 /* If we are promoting object (or for any other reason) the mode
5379 doesn't agree, convert the mode. */
5381 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
5382 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
5383 arg->value, arg->unsignedp);
5385 if (arg->pass_on_stack)
5386 stack_arg_under_construction--;
5389 /* Check for overlap with already clobbered argument area. */
5390 if ((flags & ECF_SIBCALL)
5391 && MEM_P (arg->value)
5392 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
5393 arg->locate.size.constant))
5394 sibcall_failure = 1;
5396 /* Don't allow anything left on stack from computation
5397 of argument to alloca. */
5398 if (flags & ECF_MAY_BE_ALLOCA)
5399 do_pending_stack_adjust ();
5401 if (arg->value == arg->stack)
5402 /* If the value is already in the stack slot, we are done. */
5404 else if (arg->mode != BLKmode)
5406 int size;
5407 unsigned int parm_align;
5409 /* Argument is a scalar, not entirely passed in registers.
5410 (If part is passed in registers, arg->partial says how much
5411 and emit_push_insn will take care of putting it there.)
5413 Push it, and if its size is less than the
5414 amount of space allocated to it,
5415 also bump stack pointer by the additional space.
5416 Note that in C the default argument promotions
5417 will prevent such mismatches. */
5419 size = GET_MODE_SIZE (arg->mode);
5420 /* Compute how much space the push instruction will push.
5421 On many machines, pushing a byte will advance the stack
5422 pointer by a halfword. */
5423 #ifdef PUSH_ROUNDING
5424 size = PUSH_ROUNDING (size);
5425 #endif
5426 used = size;
5428 /* Compute how much space the argument should get:
5429 round up to a multiple of the alignment for arguments. */
5430 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
5431 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
5432 / (PARM_BOUNDARY / BITS_PER_UNIT))
5433 * (PARM_BOUNDARY / BITS_PER_UNIT));
5435 /* Compute the alignment of the pushed argument. */
5436 parm_align = arg->locate.boundary;
5437 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
5439 int pad = used - size;
5440 if (pad)
5442 unsigned int pad_align = least_bit_hwi (pad) * BITS_PER_UNIT;
5443 parm_align = MIN (parm_align, pad_align);
5447 /* This isn't already where we want it on the stack, so put it there.
5448 This can either be done with push or copy insns. */
5449 if (!emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
5450 parm_align, partial, reg, used - size, argblock,
5451 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5452 ARGS_SIZE_RTX (arg->locate.alignment_pad), true))
5453 sibcall_failure = 1;
5455 /* Unless this is a partially-in-register argument, the argument is now
5456 in the stack. */
5457 if (partial == 0)
5458 arg->value = arg->stack;
5460 else
5462 /* BLKmode, at least partly to be pushed. */
5464 unsigned int parm_align;
5465 int excess;
5466 rtx size_rtx;
5468 /* Pushing a nonscalar.
5469 If part is passed in registers, PARTIAL says how much
5470 and emit_push_insn will take care of putting it there. */
5472 /* Round its size up to a multiple
5473 of the allocation unit for arguments. */
5475 if (arg->locate.size.var != 0)
5477 excess = 0;
5478 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
5480 else
5482 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
5483 for BLKmode is careful to avoid it. */
5484 excess = (arg->locate.size.constant
5485 - int_size_in_bytes (TREE_TYPE (pval))
5486 + partial);
5487 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
5488 NULL_RTX, TYPE_MODE (sizetype),
5489 EXPAND_NORMAL);
5492 parm_align = arg->locate.boundary;
5494 /* When an argument is padded down, the block is aligned to
5495 PARM_BOUNDARY, but the actual argument isn't. */
5496 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
5498 if (arg->locate.size.var)
5499 parm_align = BITS_PER_UNIT;
5500 else if (excess)
5502 unsigned int excess_align = least_bit_hwi (excess) * BITS_PER_UNIT;
5503 parm_align = MIN (parm_align, excess_align);
5507 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
5509 /* emit_push_insn might not work properly if arg->value and
5510 argblock + arg->locate.offset areas overlap. */
5511 rtx x = arg->value;
5512 int i = 0;
5514 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
5515 || (GET_CODE (XEXP (x, 0)) == PLUS
5516 && XEXP (XEXP (x, 0), 0) ==
5517 crtl->args.internal_arg_pointer
5518 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
5520 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
5521 i = INTVAL (XEXP (XEXP (x, 0), 1));
5523 /* arg.locate doesn't contain the pretend_args_size offset,
5524 it's part of argblock. Ensure we don't count it in I. */
5525 if (STACK_GROWS_DOWNWARD)
5526 i -= crtl->args.pretend_args_size;
5527 else
5528 i += crtl->args.pretend_args_size;
5530 /* expand_call should ensure this. */
5531 gcc_assert (!arg->locate.offset.var
5532 && arg->locate.size.var == 0
5533 && CONST_INT_P (size_rtx));
5535 if (arg->locate.offset.constant > i)
5537 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
5538 sibcall_failure = 1;
5540 else if (arg->locate.offset.constant < i)
5542 /* Use arg->locate.size.constant instead of size_rtx
5543 because we only care about the part of the argument
5544 on the stack. */
5545 if (i < (arg->locate.offset.constant
5546 + arg->locate.size.constant))
5547 sibcall_failure = 1;
5549 else
5551 /* Even though they appear to be at the same location,
5552 if part of the outgoing argument is in registers,
5553 they aren't really at the same location. Check for
5554 this by making sure that the incoming size is the
5555 same as the outgoing size. */
5556 if (arg->locate.size.constant != INTVAL (size_rtx))
5557 sibcall_failure = 1;
5562 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
5563 parm_align, partial, reg, excess, argblock,
5564 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
5565 ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
5567 /* Unless this is a partially-in-register argument, the argument is now
5568 in the stack.
5570 ??? Unlike the case above, in which we want the actual
5571 address of the data, so that we can load it directly into a
5572 register, here we want the address of the stack slot, so that
5573 it's properly aligned for word-by-word copying or something
5574 like that. It's not clear that this is always correct. */
5575 if (partial == 0)
5576 arg->value = arg->stack_slot;
5579 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
5581 tree type = TREE_TYPE (arg->tree_value);
5582 arg->parallel_value
5583 = emit_group_load_into_temps (arg->reg, arg->value, type,
5584 int_size_in_bytes (type));
5587 /* Mark all slots this store used. */
5588 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
5589 && argblock && ! variable_size && arg->stack)
5590 for (i = lower_bound; i < upper_bound; i++)
5591 stack_usage_map[i] = 1;
5593 /* Once we have pushed something, pops can't safely
5594 be deferred during the rest of the arguments. */
5595 NO_DEFER_POP;
5597 /* Free any temporary slots made in processing this argument. */
5598 pop_temp_slots ();
5600 return sibcall_failure;
5603 /* Nonzero if we do not know how to pass TYPE solely in registers. */
5605 bool
5606 must_pass_in_stack_var_size (machine_mode mode ATTRIBUTE_UNUSED,
5607 const_tree type)
5609 if (!type)
5610 return false;
5612 /* If the type has variable size... */
5613 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5614 return true;
5616 /* If the type is marked as addressable (it is required
5617 to be constructed into the stack)... */
5618 if (TREE_ADDRESSABLE (type))
5619 return true;
5621 return false;
5624 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
5625 takes trailing padding of a structure into account. */
5626 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
5628 bool
5629 must_pass_in_stack_var_size_or_pad (machine_mode mode, const_tree type)
5631 if (!type)
5632 return false;
5634 /* If the type has variable size... */
5635 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5636 return true;
5638 /* If the type is marked as addressable (it is required
5639 to be constructed into the stack)... */
5640 if (TREE_ADDRESSABLE (type))
5641 return true;
5643 /* If the padding and mode of the type is such that a copy into
5644 a register would put it into the wrong part of the register. */
5645 if (mode == BLKmode
5646 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
5647 && (FUNCTION_ARG_PADDING (mode, type)
5648 == (BYTES_BIG_ENDIAN ? upward : downward)))
5649 return true;
5651 return false;
5654 /* Tell the garbage collector about GTY markers in this source file. */
5655 #include "gt-calls.h"