1 /* Convert function calls to rtl insns, for GNU C compiler.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
35 #include "diagnostic-core.h"
40 #include "langhooks.h"
45 #include "tree-flow.h"
47 /* Like PREFERRED_STACK_BOUNDARY but in units of bytes, not bits. */
48 #define STACK_BYTES (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)
50 /* Data structure and subroutines used within expand_call. */
54 /* Tree node for this argument. */
56 /* Mode for value; TYPE_MODE unless promoted. */
57 enum machine_mode mode;
58 /* Current RTL value for argument, or 0 if it isn't precomputed. */
60 /* Initially-compute RTL value for argument; only for const functions. */
62 /* Register to pass this argument in, 0 if passed on stack, or an
63 PARALLEL if the arg is to be copied into multiple non-contiguous
66 /* Register to pass this argument in when generating tail call sequence.
67 This is not the same register as for normal calls on machines with
70 /* If REG is a PARALLEL, this is a copy of VALUE pulled into the correct
71 form for emit_group_move. */
73 /* If REG was promoted from the actual mode of the argument expression,
74 indicates whether the promotion is sign- or zero-extended. */
76 /* Number of bytes to put in registers. 0 means put the whole arg
77 in registers. Also 0 if not passed in registers. */
79 /* Nonzero if argument must be passed on stack.
80 Note that some arguments may be passed on the stack
81 even though pass_on_stack is zero, just because FUNCTION_ARG says so.
82 pass_on_stack identifies arguments that *cannot* go in registers. */
84 /* Some fields packaged up for locate_and_pad_parm. */
85 struct locate_and_pad_arg_data locate;
86 /* Location on the stack at which parameter should be stored. The store
87 has already been done if STACK == VALUE. */
89 /* Location on the stack of the start of this argument slot. This can
90 differ from STACK if this arg pads downward. This location is known
91 to be aligned to TARGET_FUNCTION_ARG_BOUNDARY. */
93 /* Place that this stack area has been saved, if needed. */
95 /* If an argument's alignment does not permit direct copying into registers,
96 copy in smaller-sized pieces into pseudos. These are stored in a
97 block pointed to by this field. The next field says how many
98 word-sized pseudos we made. */
103 /* A vector of one char per byte of stack space. A byte if nonzero if
104 the corresponding stack location has been used.
105 This vector is used to prevent a function call within an argument from
106 clobbering any stack already set up. */
107 static char *stack_usage_map;
109 /* Size of STACK_USAGE_MAP. */
110 static int highest_outgoing_arg_in_use;
112 /* A bitmap of virtual-incoming stack space. Bit is set if the corresponding
113 stack location's tail call argument has been already stored into the stack.
114 This bitmap is used to prevent sibling call optimization if function tries
115 to use parent's incoming argument slots when they have been already
116 overwritten with tail call arguments. */
117 static sbitmap stored_args_map;
119 /* stack_arg_under_construction is nonzero when an argument may be
120 initialized with a constructor call (including a C function that
121 returns a BLKmode struct) and expand_call must take special action
122 to make sure the object being constructed does not overlap the
123 argument list for the constructor call. */
124 static int stack_arg_under_construction;
126 static void emit_call_1 (rtx, tree, tree, tree, HOST_WIDE_INT, HOST_WIDE_INT,
127 HOST_WIDE_INT, rtx, rtx, int, rtx, int,
129 static void precompute_register_parameters (int, struct arg_data *, int *);
130 static int store_one_arg (struct arg_data *, rtx, int, int, int);
131 static void store_unaligned_arguments_into_pseudos (struct arg_data *, int);
132 static int finalize_must_preallocate (int, int, struct arg_data *,
134 static void precompute_arguments (int, struct arg_data *);
135 static int compute_argument_block_size (int, struct args_size *, tree, tree, int);
136 static void initialize_argument_information (int, struct arg_data *,
137 struct args_size *, int,
139 tree, tree, cumulative_args_t, int,
140 rtx *, int *, int *, int *,
142 static void compute_argument_addresses (struct arg_data *, rtx, int);
143 static rtx rtx_for_function_call (tree, tree);
144 static void load_register_parameters (struct arg_data *, int, rtx *, int,
146 static rtx emit_library_call_value_1 (int, rtx, rtx, enum libcall_type,
147 enum machine_mode, int, va_list);
148 static int special_function_p (const_tree, int);
149 static int check_sibcall_argument_overlap_1 (rtx);
150 static int check_sibcall_argument_overlap (rtx, struct arg_data *, int);
152 static int combine_pending_stack_adjustment_and_call (int, struct args_size *,
154 static tree split_complex_types (tree);
156 #ifdef REG_PARM_STACK_SPACE
157 static rtx save_fixed_argument_area (int, rtx, int *, int *);
158 static void restore_fixed_argument_area (rtx, rtx, int, int);
161 /* Force FUNEXP into a form suitable for the address of a CALL,
162 and return that as an rtx. Also load the static chain register
163 if FNDECL is a nested function.
165 CALL_FUSAGE points to a variable holding the prospective
166 CALL_INSN_FUNCTION_USAGE information. */
169 prepare_call_address (tree fndecl, rtx funexp, rtx static_chain_value,
170 rtx *call_fusage, int reg_parm_seen, int sibcallp)
172 /* Make a valid memory address and copy constants through pseudo-regs,
173 but not for a constant address if -fno-function-cse. */
174 if (GET_CODE (funexp) != SYMBOL_REF)
175 /* If we are using registers for parameters, force the
176 function address into a register now. */
177 funexp = ((reg_parm_seen
178 && targetm.small_register_classes_for_mode_p (FUNCTION_MODE))
179 ? force_not_mem (memory_address (FUNCTION_MODE, funexp))
180 : memory_address (FUNCTION_MODE, funexp));
183 #ifndef NO_FUNCTION_CSE
184 if (optimize && ! flag_no_function_cse)
185 funexp = force_reg (Pmode, funexp);
189 if (static_chain_value != 0)
194 chain = targetm.calls.static_chain (fndecl, false);
195 static_chain_value = convert_memory_address (Pmode, static_chain_value);
197 emit_move_insn (chain, static_chain_value);
199 use_reg (call_fusage, chain);
205 /* Generate instructions to call function FUNEXP,
206 and optionally pop the results.
207 The CALL_INSN is the first insn generated.
209 FNDECL is the declaration node of the function. This is given to the
210 hook TARGET_RETURN_POPS_ARGS to determine whether this function pops
213 FUNTYPE is the data type of the function. This is given to the hook
214 TARGET_RETURN_POPS_ARGS to determine whether this function pops its
215 own args. We used to allow an identifier for library functions, but
216 that doesn't work when the return type is an aggregate type and the
217 calling convention says that the pointer to this aggregate is to be
218 popped by the callee.
220 STACK_SIZE is the number of bytes of arguments on the stack,
221 ROUNDED_STACK_SIZE is that number rounded up to
222 PREFERRED_STACK_BOUNDARY; zero if the size is variable. This is
223 both to put into the call insn and to generate explicit popping
226 STRUCT_VALUE_SIZE is the number of bytes wanted in a structure value.
227 It is zero if this call doesn't want a structure value.
229 NEXT_ARG_REG is the rtx that results from executing
230 targetm.calls.function_arg (&args_so_far, VOIDmode, void_type_node, true)
231 just after all the args have had their registers assigned.
232 This could be whatever you like, but normally it is the first
233 arg-register beyond those used for args in this call,
234 or 0 if all the arg-registers are used in this call.
235 It is passed on to `gen_call' so you can put this info in the call insn.
237 VALREG is a hard register in which a value is returned,
238 or 0 if the call does not return a value.
240 OLD_INHIBIT_DEFER_POP is the value that `inhibit_defer_pop' had before
241 the args to this call were processed.
242 We restore `inhibit_defer_pop' to that value.
244 CALL_FUSAGE is either empty or an EXPR_LIST of USE expressions that
245 denote registers used by the called function. */
248 emit_call_1 (rtx funexp, tree fntree ATTRIBUTE_UNUSED, tree fndecl ATTRIBUTE_UNUSED,
249 tree funtype ATTRIBUTE_UNUSED,
250 HOST_WIDE_INT stack_size ATTRIBUTE_UNUSED,
251 HOST_WIDE_INT rounded_stack_size,
252 HOST_WIDE_INT struct_value_size ATTRIBUTE_UNUSED,
253 rtx next_arg_reg ATTRIBUTE_UNUSED, rtx valreg,
254 int old_inhibit_defer_pop, rtx call_fusage, int ecf_flags,
255 cumulative_args_t args_so_far ATTRIBUTE_UNUSED)
257 rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
258 rtx call_insn, call, funmem;
259 int already_popped = 0;
260 HOST_WIDE_INT n_popped
261 = targetm.calls.return_pops_args (fndecl, funtype, stack_size);
263 #ifdef CALL_POPS_ARGS
264 n_popped += CALL_POPS_ARGS (*get_cumulative_args (args_so_far));
267 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
268 and we don't want to load it into a register as an optimization,
269 because prepare_call_address already did it if it should be done. */
270 if (GET_CODE (funexp) != SYMBOL_REF)
271 funexp = memory_address (FUNCTION_MODE, funexp);
273 funmem = gen_rtx_MEM (FUNCTION_MODE, funexp);
274 if (fndecl && TREE_CODE (fndecl) == FUNCTION_DECL)
278 /* Although a built-in FUNCTION_DECL and its non-__builtin
279 counterpart compare equal and get a shared mem_attrs, they
280 produce different dump output in compare-debug compilations,
281 if an entry gets garbage collected in one compilation, then
282 adds a different (but equivalent) entry, while the other
283 doesn't run the garbage collector at the same spot and then
284 shares the mem_attr with the equivalent entry. */
285 if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
287 tree t2 = builtin_decl_explicit (DECL_FUNCTION_CODE (t));
292 set_mem_expr (funmem, t);
295 set_mem_expr (funmem, build_simple_mem_ref (CALL_EXPR_FN (fntree)));
297 #if defined (HAVE_sibcall_pop) && defined (HAVE_sibcall_value_pop)
298 if ((ecf_flags & ECF_SIBCALL)
299 && HAVE_sibcall_pop && HAVE_sibcall_value_pop
300 && (n_popped > 0 || stack_size == 0))
302 rtx n_pop = GEN_INT (n_popped);
305 /* If this subroutine pops its own args, record that in the call insn
306 if possible, for the sake of frame pointer elimination. */
309 pat = GEN_SIBCALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
310 next_arg_reg, n_pop);
312 pat = GEN_SIBCALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
315 emit_call_insn (pat);
321 #if defined (HAVE_call_pop) && defined (HAVE_call_value_pop)
322 /* If the target has "call" or "call_value" insns, then prefer them
323 if no arguments are actually popped. If the target does not have
324 "call" or "call_value" insns, then we must use the popping versions
325 even if the call has no arguments to pop. */
326 #if defined (HAVE_call) && defined (HAVE_call_value)
327 if (HAVE_call && HAVE_call_value && HAVE_call_pop && HAVE_call_value_pop
330 if (HAVE_call_pop && HAVE_call_value_pop)
333 rtx n_pop = GEN_INT (n_popped);
336 /* If this subroutine pops its own args, record that in the call insn
337 if possible, for the sake of frame pointer elimination. */
340 pat = GEN_CALL_VALUE_POP (valreg, funmem, rounded_stack_size_rtx,
341 next_arg_reg, n_pop);
343 pat = GEN_CALL_POP (funmem, rounded_stack_size_rtx, next_arg_reg,
346 emit_call_insn (pat);
352 #if defined (HAVE_sibcall) && defined (HAVE_sibcall_value)
353 if ((ecf_flags & ECF_SIBCALL)
354 && HAVE_sibcall && HAVE_sibcall_value)
357 emit_call_insn (GEN_SIBCALL_VALUE (valreg, funmem,
358 rounded_stack_size_rtx,
359 next_arg_reg, NULL_RTX));
361 emit_call_insn (GEN_SIBCALL (funmem, rounded_stack_size_rtx,
363 GEN_INT (struct_value_size)));
368 #if defined (HAVE_call) && defined (HAVE_call_value)
369 if (HAVE_call && HAVE_call_value)
372 emit_call_insn (GEN_CALL_VALUE (valreg, funmem, rounded_stack_size_rtx,
373 next_arg_reg, NULL_RTX));
375 emit_call_insn (GEN_CALL (funmem, rounded_stack_size_rtx, next_arg_reg,
376 GEN_INT (struct_value_size)));
382 /* Find the call we just emitted. */
383 call_insn = last_call_insn ();
385 /* Some target create a fresh MEM instead of reusing the one provided
386 above. Set its MEM_EXPR. */
387 call = PATTERN (call_insn);
388 if (GET_CODE (call) == PARALLEL)
389 call = XVECEXP (call, 0, 0);
390 if (GET_CODE (call) == SET)
391 call = SET_SRC (call);
392 if (GET_CODE (call) == CALL
393 && MEM_P (XEXP (call, 0))
394 && MEM_EXPR (XEXP (call, 0)) == NULL_TREE
395 && MEM_EXPR (funmem) != NULL_TREE)
396 set_mem_expr (XEXP (call, 0), MEM_EXPR (funmem));
398 /* Put the register usage information there. */
399 add_function_usage_to (call_insn, call_fusage);
401 /* If this is a const call, then set the insn's unchanging bit. */
402 if (ecf_flags & ECF_CONST)
403 RTL_CONST_CALL_P (call_insn) = 1;
405 /* If this is a pure call, then set the insn's unchanging bit. */
406 if (ecf_flags & ECF_PURE)
407 RTL_PURE_CALL_P (call_insn) = 1;
409 /* If this is a const call, then set the insn's unchanging bit. */
410 if (ecf_flags & ECF_LOOPING_CONST_OR_PURE)
411 RTL_LOOPING_CONST_OR_PURE_CALL_P (call_insn) = 1;
413 /* Create a nothrow REG_EH_REGION note, if needed. */
414 make_reg_eh_region_note (call_insn, ecf_flags, 0);
416 if (ecf_flags & ECF_NORETURN)
417 add_reg_note (call_insn, REG_NORETURN, const0_rtx);
419 if (ecf_flags & ECF_RETURNS_TWICE)
421 add_reg_note (call_insn, REG_SETJMP, const0_rtx);
422 cfun->calls_setjmp = 1;
425 SIBLING_CALL_P (call_insn) = ((ecf_flags & ECF_SIBCALL) != 0);
427 /* Restore this now, so that we do defer pops for this call's args
428 if the context of the call as a whole permits. */
429 inhibit_defer_pop = old_inhibit_defer_pop;
434 CALL_INSN_FUNCTION_USAGE (call_insn)
435 = gen_rtx_EXPR_LIST (VOIDmode,
436 gen_rtx_CLOBBER (VOIDmode, stack_pointer_rtx),
437 CALL_INSN_FUNCTION_USAGE (call_insn));
438 rounded_stack_size -= n_popped;
439 rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
440 stack_pointer_delta -= n_popped;
442 add_reg_note (call_insn, REG_ARGS_SIZE, GEN_INT (stack_pointer_delta));
444 /* If popup is needed, stack realign must use DRAP */
445 if (SUPPORTS_STACK_ALIGNMENT)
446 crtl->need_drap = true;
449 if (!ACCUMULATE_OUTGOING_ARGS)
451 /* If returning from the subroutine does not automatically pop the args,
452 we need an instruction to pop them sooner or later.
453 Perhaps do it now; perhaps just record how much space to pop later.
455 If returning from the subroutine does pop the args, indicate that the
456 stack pointer will be changed. */
458 if (rounded_stack_size != 0)
460 if (ecf_flags & ECF_NORETURN)
461 /* Just pretend we did the pop. */
462 stack_pointer_delta -= rounded_stack_size;
463 else if (flag_defer_pop && inhibit_defer_pop == 0
464 && ! (ecf_flags & (ECF_CONST | ECF_PURE)))
465 pending_stack_adjust += rounded_stack_size;
467 adjust_stack (rounded_stack_size_rtx);
470 /* When we accumulate outgoing args, we must avoid any stack manipulations.
471 Restore the stack pointer to its original value now. Usually
472 ACCUMULATE_OUTGOING_ARGS targets don't get here, but there are exceptions.
473 On i386 ACCUMULATE_OUTGOING_ARGS can be enabled on demand, and
474 popping variants of functions exist as well.
476 ??? We may optimize similar to defer_pop above, but it is
477 probably not worthwhile.
479 ??? It will be worthwhile to enable combine_stack_adjustments even for
482 anti_adjust_stack (GEN_INT (n_popped));
485 /* Determine if the function identified by NAME and FNDECL is one with
486 special properties we wish to know about.
488 For example, if the function might return more than one time (setjmp), then
489 set RETURNS_TWICE to a nonzero value.
491 Similarly set NORETURN if the function is in the longjmp family.
493 Set MAY_BE_ALLOCA for any memory allocation function that might allocate
494 space from the stack such as alloca. */
497 special_function_p (const_tree fndecl, int flags)
499 if (fndecl && DECL_NAME (fndecl)
500 && IDENTIFIER_LENGTH (DECL_NAME (fndecl)) <= 17
501 /* Exclude functions not at the file scope, or not `extern',
502 since they are not the magic functions we would otherwise
504 FIXME: this should be handled with attributes, not with this
505 hacky imitation of DECL_ASSEMBLER_NAME. It's (also) wrong
506 because you can declare fork() inside a function if you
508 && (DECL_CONTEXT (fndecl) == NULL_TREE
509 || TREE_CODE (DECL_CONTEXT (fndecl)) == TRANSLATION_UNIT_DECL)
510 && TREE_PUBLIC (fndecl))
512 const char *name = IDENTIFIER_POINTER (DECL_NAME (fndecl));
513 const char *tname = name;
515 /* We assume that alloca will always be called by name. It
516 makes no sense to pass it as a pointer-to-function to
517 anything that does not understand its behavior. */
518 if (((IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 6
520 && ! strcmp (name, "alloca"))
521 || (IDENTIFIER_LENGTH (DECL_NAME (fndecl)) == 16
523 && ! strcmp (name, "__builtin_alloca"))))
524 flags |= ECF_MAY_BE_ALLOCA;
526 /* Disregard prefix _, __, __x or __builtin_. */
531 && !strncmp (name + 3, "uiltin_", 7))
533 else if (name[1] == '_' && name[2] == 'x')
535 else if (name[1] == '_')
544 && (! strcmp (tname, "setjmp")
545 || ! strcmp (tname, "setjmp_syscall")))
547 && ! strcmp (tname, "sigsetjmp"))
549 && ! strcmp (tname, "savectx")))
550 flags |= ECF_RETURNS_TWICE;
553 && ! strcmp (tname, "siglongjmp"))
554 flags |= ECF_NORETURN;
556 else if ((tname[0] == 'q' && tname[1] == 's'
557 && ! strcmp (tname, "qsetjmp"))
558 || (tname[0] == 'v' && tname[1] == 'f'
559 && ! strcmp (tname, "vfork"))
560 || (tname[0] == 'g' && tname[1] == 'e'
561 && !strcmp (tname, "getcontext")))
562 flags |= ECF_RETURNS_TWICE;
564 else if (tname[0] == 'l' && tname[1] == 'o'
565 && ! strcmp (tname, "longjmp"))
566 flags |= ECF_NORETURN;
572 /* Return nonzero when FNDECL represents a call to setjmp. */
575 setjmp_call_p (const_tree fndecl)
577 if (DECL_IS_RETURNS_TWICE (fndecl))
578 return ECF_RETURNS_TWICE;
579 return special_function_p (fndecl, 0) & ECF_RETURNS_TWICE;
583 /* Return true if STMT is an alloca call. */
586 gimple_alloca_call_p (const_gimple stmt)
590 if (!is_gimple_call (stmt))
593 fndecl = gimple_call_fndecl (stmt);
594 if (fndecl && (special_function_p (fndecl, 0) & ECF_MAY_BE_ALLOCA))
600 /* Return true when exp contains alloca call. */
603 alloca_call_p (const_tree exp)
605 if (TREE_CODE (exp) == CALL_EXPR
606 && TREE_CODE (CALL_EXPR_FN (exp)) == ADDR_EXPR
607 && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp), 0)) == FUNCTION_DECL)
608 && (special_function_p (TREE_OPERAND (CALL_EXPR_FN (exp), 0), 0)
609 & ECF_MAY_BE_ALLOCA))
614 /* Return TRUE if FNDECL is either a TM builtin or a TM cloned
615 function. Return FALSE otherwise. */
618 is_tm_builtin (const_tree fndecl)
623 if (decl_is_tm_clone (fndecl))
626 if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
628 switch (DECL_FUNCTION_CODE (fndecl))
630 case BUILT_IN_TM_COMMIT:
631 case BUILT_IN_TM_COMMIT_EH:
632 case BUILT_IN_TM_ABORT:
633 case BUILT_IN_TM_IRREVOCABLE:
634 case BUILT_IN_TM_GETTMCLONE_IRR:
635 case BUILT_IN_TM_MEMCPY:
636 case BUILT_IN_TM_MEMMOVE:
637 case BUILT_IN_TM_MEMSET:
638 CASE_BUILT_IN_TM_STORE (1):
639 CASE_BUILT_IN_TM_STORE (2):
640 CASE_BUILT_IN_TM_STORE (4):
641 CASE_BUILT_IN_TM_STORE (8):
642 CASE_BUILT_IN_TM_STORE (FLOAT):
643 CASE_BUILT_IN_TM_STORE (DOUBLE):
644 CASE_BUILT_IN_TM_STORE (LDOUBLE):
645 CASE_BUILT_IN_TM_STORE (M64):
646 CASE_BUILT_IN_TM_STORE (M128):
647 CASE_BUILT_IN_TM_STORE (M256):
648 CASE_BUILT_IN_TM_LOAD (1):
649 CASE_BUILT_IN_TM_LOAD (2):
650 CASE_BUILT_IN_TM_LOAD (4):
651 CASE_BUILT_IN_TM_LOAD (8):
652 CASE_BUILT_IN_TM_LOAD (FLOAT):
653 CASE_BUILT_IN_TM_LOAD (DOUBLE):
654 CASE_BUILT_IN_TM_LOAD (LDOUBLE):
655 CASE_BUILT_IN_TM_LOAD (M64):
656 CASE_BUILT_IN_TM_LOAD (M128):
657 CASE_BUILT_IN_TM_LOAD (M256):
658 case BUILT_IN_TM_LOG:
659 case BUILT_IN_TM_LOG_1:
660 case BUILT_IN_TM_LOG_2:
661 case BUILT_IN_TM_LOG_4:
662 case BUILT_IN_TM_LOG_8:
663 case BUILT_IN_TM_LOG_FLOAT:
664 case BUILT_IN_TM_LOG_DOUBLE:
665 case BUILT_IN_TM_LOG_LDOUBLE:
666 case BUILT_IN_TM_LOG_M64:
667 case BUILT_IN_TM_LOG_M128:
668 case BUILT_IN_TM_LOG_M256:
677 /* Detect flags (function attributes) from the function decl or type node. */
680 flags_from_decl_or_type (const_tree exp)
686 /* The function exp may have the `malloc' attribute. */
687 if (DECL_IS_MALLOC (exp))
690 /* The function exp may have the `returns_twice' attribute. */
691 if (DECL_IS_RETURNS_TWICE (exp))
692 flags |= ECF_RETURNS_TWICE;
694 /* Process the pure and const attributes. */
695 if (TREE_READONLY (exp))
697 if (DECL_PURE_P (exp))
699 if (DECL_LOOPING_CONST_OR_PURE_P (exp))
700 flags |= ECF_LOOPING_CONST_OR_PURE;
702 if (DECL_IS_NOVOPS (exp))
704 if (lookup_attribute ("leaf", DECL_ATTRIBUTES (exp)))
707 if (TREE_NOTHROW (exp))
708 flags |= ECF_NOTHROW;
712 if (is_tm_builtin (exp))
713 flags |= ECF_TM_BUILTIN;
714 else if ((flags & ECF_CONST) != 0
715 || lookup_attribute ("transaction_pure",
716 TYPE_ATTRIBUTES (TREE_TYPE (exp))))
717 flags |= ECF_TM_PURE;
720 flags = special_function_p (exp, flags);
722 else if (TYPE_P (exp))
724 if (TYPE_READONLY (exp))
728 && ((flags & ECF_CONST) != 0
729 || lookup_attribute ("transaction_pure", TYPE_ATTRIBUTES (exp))))
730 flags |= ECF_TM_PURE;
733 if (TREE_THIS_VOLATILE (exp))
735 flags |= ECF_NORETURN;
736 if (flags & (ECF_CONST|ECF_PURE))
737 flags |= ECF_LOOPING_CONST_OR_PURE;
743 /* Detect flags from a CALL_EXPR. */
746 call_expr_flags (const_tree t)
749 tree decl = get_callee_fndecl (t);
752 flags = flags_from_decl_or_type (decl);
755 t = TREE_TYPE (CALL_EXPR_FN (t));
756 if (t && TREE_CODE (t) == POINTER_TYPE)
757 flags = flags_from_decl_or_type (TREE_TYPE (t));
765 /* Precompute all register parameters as described by ARGS, storing values
766 into fields within the ARGS array.
768 NUM_ACTUALS indicates the total number elements in the ARGS array.
770 Set REG_PARM_SEEN if we encounter a register parameter. */
773 precompute_register_parameters (int num_actuals, struct arg_data *args,
780 for (i = 0; i < num_actuals; i++)
781 if (args[i].reg != 0 && ! args[i].pass_on_stack)
785 if (args[i].value == 0)
788 args[i].value = expand_normal (args[i].tree_value);
789 preserve_temp_slots (args[i].value);
793 /* If we are to promote the function arg to a wider mode,
796 if (args[i].mode != TYPE_MODE (TREE_TYPE (args[i].tree_value)))
798 = convert_modes (args[i].mode,
799 TYPE_MODE (TREE_TYPE (args[i].tree_value)),
800 args[i].value, args[i].unsignedp);
802 /* If the value is a non-legitimate constant, force it into a
803 pseudo now. TLS symbols sometimes need a call to resolve. */
804 if (CONSTANT_P (args[i].value)
805 && !targetm.legitimate_constant_p (args[i].mode, args[i].value))
806 args[i].value = force_reg (args[i].mode, args[i].value);
808 /* If we're going to have to load the value by parts, pull the
809 parts into pseudos. The part extraction process can involve
810 non-trivial computation. */
811 if (GET_CODE (args[i].reg) == PARALLEL)
813 tree type = TREE_TYPE (args[i].tree_value);
814 args[i].parallel_value
815 = emit_group_load_into_temps (args[i].reg, args[i].value,
816 type, int_size_in_bytes (type));
819 /* If the value is expensive, and we are inside an appropriately
820 short loop, put the value into a pseudo and then put the pseudo
823 For small register classes, also do this if this call uses
824 register parameters. This is to avoid reload conflicts while
825 loading the parameters registers. */
827 else if ((! (REG_P (args[i].value)
828 || (GET_CODE (args[i].value) == SUBREG
829 && REG_P (SUBREG_REG (args[i].value)))))
830 && args[i].mode != BLKmode
831 && set_src_cost (args[i].value, optimize_insn_for_speed_p ())
834 && targetm.small_register_classes_for_mode_p (args[i].mode))
836 args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
840 #ifdef REG_PARM_STACK_SPACE
842 /* The argument list is the property of the called routine and it
843 may clobber it. If the fixed area has been used for previous
844 parameters, we must save and restore it. */
847 save_fixed_argument_area (int reg_parm_stack_space, rtx argblock, int *low_to_save, int *high_to_save)
852 /* Compute the boundary of the area that needs to be saved, if any. */
853 high = reg_parm_stack_space;
854 #ifdef ARGS_GROW_DOWNWARD
857 if (high > highest_outgoing_arg_in_use)
858 high = highest_outgoing_arg_in_use;
860 for (low = 0; low < high; low++)
861 if (stack_usage_map[low] != 0)
864 enum machine_mode save_mode;
869 while (stack_usage_map[--high] == 0)
873 *high_to_save = high;
875 num_to_save = high - low + 1;
876 save_mode = mode_for_size (num_to_save * BITS_PER_UNIT, MODE_INT, 1);
878 /* If we don't have the required alignment, must do this
880 if ((low & (MIN (GET_MODE_SIZE (save_mode),
881 BIGGEST_ALIGNMENT / UNITS_PER_WORD) - 1)))
884 #ifdef ARGS_GROW_DOWNWARD
889 stack_area = gen_rtx_MEM (save_mode,
890 memory_address (save_mode,
891 plus_constant (argblock,
894 set_mem_align (stack_area, PARM_BOUNDARY);
895 if (save_mode == BLKmode)
897 save_area = assign_stack_temp (BLKmode, num_to_save, 0);
898 emit_block_move (validize_mem (save_area), stack_area,
899 GEN_INT (num_to_save), BLOCK_OP_CALL_PARM);
903 save_area = gen_reg_rtx (save_mode);
904 emit_move_insn (save_area, stack_area);
914 restore_fixed_argument_area (rtx save_area, rtx argblock, int high_to_save, int low_to_save)
916 enum machine_mode save_mode = GET_MODE (save_area);
920 #ifdef ARGS_GROW_DOWNWARD
921 delta = -high_to_save;
925 stack_area = gen_rtx_MEM (save_mode,
926 memory_address (save_mode,
927 plus_constant (argblock, delta)));
928 set_mem_align (stack_area, PARM_BOUNDARY);
930 if (save_mode != BLKmode)
931 emit_move_insn (stack_area, save_area);
933 emit_block_move (stack_area, validize_mem (save_area),
934 GEN_INT (high_to_save - low_to_save + 1),
937 #endif /* REG_PARM_STACK_SPACE */
939 /* If any elements in ARGS refer to parameters that are to be passed in
940 registers, but not in memory, and whose alignment does not permit a
941 direct copy into registers. Copy the values into a group of pseudos
942 which we will later copy into the appropriate hard registers.
944 Pseudos for each unaligned argument will be stored into the array
945 args[argnum].aligned_regs. The caller is responsible for deallocating
946 the aligned_regs array if it is nonzero. */
949 store_unaligned_arguments_into_pseudos (struct arg_data *args, int num_actuals)
953 for (i = 0; i < num_actuals; i++)
954 if (args[i].reg != 0 && ! args[i].pass_on_stack
955 && args[i].mode == BLKmode
956 && MEM_P (args[i].value)
957 && (MEM_ALIGN (args[i].value)
958 < (unsigned int) MIN (BIGGEST_ALIGNMENT, BITS_PER_WORD)))
960 int bytes = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
961 int endian_correction = 0;
965 gcc_assert (args[i].partial % UNITS_PER_WORD == 0);
966 args[i].n_aligned_regs = args[i].partial / UNITS_PER_WORD;
970 args[i].n_aligned_regs
971 = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
974 args[i].aligned_regs = XNEWVEC (rtx, args[i].n_aligned_regs);
976 /* Structures smaller than a word are normally aligned to the
977 least significant byte. On a BYTES_BIG_ENDIAN machine,
978 this means we must skip the empty high order bytes when
979 calculating the bit offset. */
980 if (bytes < UNITS_PER_WORD
981 #ifdef BLOCK_REG_PADDING
982 && (BLOCK_REG_PADDING (args[i].mode,
983 TREE_TYPE (args[i].tree_value), 1)
989 endian_correction = BITS_PER_WORD - bytes * BITS_PER_UNIT;
991 for (j = 0; j < args[i].n_aligned_regs; j++)
993 rtx reg = gen_reg_rtx (word_mode);
994 rtx word = operand_subword_force (args[i].value, j, BLKmode);
995 int bitsize = MIN (bytes * BITS_PER_UNIT, BITS_PER_WORD);
997 args[i].aligned_regs[j] = reg;
998 word = extract_bit_field (word, bitsize, 0, 1, false, NULL_RTX,
999 word_mode, word_mode);
1001 /* There is no need to restrict this code to loading items
1002 in TYPE_ALIGN sized hunks. The bitfield instructions can
1003 load up entire word sized registers efficiently.
1005 ??? This may not be needed anymore.
1006 We use to emit a clobber here but that doesn't let later
1007 passes optimize the instructions we emit. By storing 0 into
1008 the register later passes know the first AND to zero out the
1009 bitfield being set in the register is unnecessary. The store
1010 of 0 will be deleted as will at least the first AND. */
1012 emit_move_insn (reg, const0_rtx);
1014 bytes -= bitsize / BITS_PER_UNIT;
1015 store_bit_field (reg, bitsize, endian_correction, 0, 0,
1021 /* Fill in ARGS_SIZE and ARGS array based on the parameters found in
1024 NUM_ACTUALS is the total number of parameters.
1026 N_NAMED_ARGS is the total number of named arguments.
1028 STRUCT_VALUE_ADDR_VALUE is the implicit argument for a struct return
1031 FNDECL is the tree code for the target of this call (if known)
1033 ARGS_SO_FAR holds state needed by the target to know where to place
1036 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
1037 for arguments which are passed in registers.
1039 OLD_STACK_LEVEL is a pointer to an rtx which olds the old stack level
1040 and may be modified by this routine.
1042 OLD_PENDING_ADJ, MUST_PREALLOCATE and FLAGS are pointers to integer
1043 flags which may may be modified by this routine.
1045 MAY_TAILCALL is cleared if we encounter an invisible pass-by-reference
1046 that requires allocation of stack space.
1048 CALL_FROM_THUNK_P is true if this call is the jump from a thunk to
1049 the thunked-to function. */
1052 initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
1053 struct arg_data *args,
1054 struct args_size *args_size,
1055 int n_named_args ATTRIBUTE_UNUSED,
1056 tree exp, tree struct_value_addr_value,
1057 tree fndecl, tree fntype,
1058 cumulative_args_t args_so_far,
1059 int reg_parm_stack_space,
1060 rtx *old_stack_level, int *old_pending_adj,
1061 int *must_preallocate, int *ecf_flags,
1062 bool *may_tailcall, bool call_from_thunk_p)
1064 CUMULATIVE_ARGS *args_so_far_pnt = get_cumulative_args (args_so_far);
1065 location_t loc = EXPR_LOCATION (exp);
1066 /* 1 if scanning parms front to back, -1 if scanning back to front. */
1069 /* Count arg position in order args appear. */
1074 args_size->constant = 0;
1077 /* In this loop, we consider args in the order they are written.
1078 We fill up ARGS from the front or from the back if necessary
1079 so that in any case the first arg to be pushed ends up at the front. */
1081 if (PUSH_ARGS_REVERSED)
1083 i = num_actuals - 1, inc = -1;
1084 /* In this case, must reverse order of args
1085 so that we compute and push the last arg first. */
1092 /* First fill in the actual arguments in the ARGS array, splitting
1093 complex arguments if necessary. */
1096 call_expr_arg_iterator iter;
1099 if (struct_value_addr_value)
1101 args[j].tree_value = struct_value_addr_value;
1104 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
1106 tree argtype = TREE_TYPE (arg);
1107 if (targetm.calls.split_complex_arg
1109 && TREE_CODE (argtype) == COMPLEX_TYPE
1110 && targetm.calls.split_complex_arg (argtype))
1112 tree subtype = TREE_TYPE (argtype);
1113 args[j].tree_value = build1 (REALPART_EXPR, subtype, arg);
1115 args[j].tree_value = build1 (IMAGPART_EXPR, subtype, arg);
1118 args[j].tree_value = arg;
1123 /* I counts args in order (to be) pushed; ARGPOS counts in order written. */
1124 for (argpos = 0; argpos < num_actuals; i += inc, argpos++)
1126 tree type = TREE_TYPE (args[i].tree_value);
1128 enum machine_mode mode;
1130 /* Replace erroneous argument with constant zero. */
1131 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1132 args[i].tree_value = integer_zero_node, type = integer_type_node;
1134 /* If TYPE is a transparent union or record, pass things the way
1135 we would pass the first field of the union or record. We have
1136 already verified that the modes are the same. */
1137 if ((TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == RECORD_TYPE)
1138 && TYPE_TRANSPARENT_AGGR (type))
1139 type = TREE_TYPE (first_field (type));
1141 /* Decide where to pass this arg.
1143 args[i].reg is nonzero if all or part is passed in registers.
1145 args[i].partial is nonzero if part but not all is passed in registers,
1146 and the exact value says how many bytes are passed in registers.
1148 args[i].pass_on_stack is nonzero if the argument must at least be
1149 computed on the stack. It may then be loaded back into registers
1150 if args[i].reg is nonzero.
1152 These decisions are driven by the FUNCTION_... macros and must agree
1153 with those made by function.c. */
1155 /* See if this argument should be passed by invisible reference. */
1156 if (pass_by_reference (args_so_far_pnt, TYPE_MODE (type),
1157 type, argpos < n_named_args))
1163 = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
1164 type, argpos < n_named_args);
1166 /* If we're compiling a thunk, pass through invisible references
1167 instead of making a copy. */
1168 if (call_from_thunk_p
1170 && !TREE_ADDRESSABLE (type)
1171 && (base = get_base_address (args[i].tree_value))
1172 && TREE_CODE (base) != SSA_NAME
1173 && (!DECL_P (base) || MEM_P (DECL_RTL (base)))))
1175 mark_addressable (args[i].tree_value);
1177 /* We can't use sibcalls if a callee-copied argument is
1178 stored in the current function's frame. */
1179 if (!call_from_thunk_p && DECL_P (base) && !TREE_STATIC (base))
1180 *may_tailcall = false;
1182 args[i].tree_value = build_fold_addr_expr_loc (loc,
1183 args[i].tree_value);
1184 type = TREE_TYPE (args[i].tree_value);
1186 if (*ecf_flags & ECF_CONST)
1187 *ecf_flags &= ~(ECF_CONST | ECF_LOOPING_CONST_OR_PURE);
1191 /* We make a copy of the object and pass the address to the
1192 function being called. */
1195 if (!COMPLETE_TYPE_P (type)
1196 || TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST
1197 || (flag_stack_check == GENERIC_STACK_CHECK
1198 && compare_tree_int (TYPE_SIZE_UNIT (type),
1199 STACK_CHECK_MAX_VAR_SIZE) > 0))
1201 /* This is a variable-sized object. Make space on the stack
1203 rtx size_rtx = expr_size (args[i].tree_value);
1205 if (*old_stack_level == 0)
1207 emit_stack_save (SAVE_BLOCK, old_stack_level);
1208 *old_pending_adj = pending_stack_adjust;
1209 pending_stack_adjust = 0;
1212 /* We can pass TRUE as the 4th argument because we just
1213 saved the stack pointer and will restore it right after
1215 copy = allocate_dynamic_stack_space (size_rtx,
1219 copy = gen_rtx_MEM (BLKmode, copy);
1220 set_mem_attributes (copy, type, 1);
1223 copy = assign_temp (type, 0, 1, 0);
1225 store_expr (args[i].tree_value, copy, 0, false);
1227 /* Just change the const function to pure and then let
1228 the next test clear the pure based on
1230 if (*ecf_flags & ECF_CONST)
1232 *ecf_flags &= ~ECF_CONST;
1233 *ecf_flags |= ECF_PURE;
1236 if (!callee_copies && *ecf_flags & ECF_PURE)
1237 *ecf_flags &= ~(ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
1240 = build_fold_addr_expr_loc (loc, make_tree (type, copy));
1241 type = TREE_TYPE (args[i].tree_value);
1242 *may_tailcall = false;
1246 unsignedp = TYPE_UNSIGNED (type);
1247 mode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
1248 fndecl ? TREE_TYPE (fndecl) : fntype, 0);
1250 args[i].unsignedp = unsignedp;
1251 args[i].mode = mode;
1253 args[i].reg = targetm.calls.function_arg (args_so_far, mode, type,
1254 argpos < n_named_args);
1256 /* If this is a sibling call and the machine has register windows, the
1257 register window has to be unwinded before calling the routine, so
1258 arguments have to go into the incoming registers. */
1259 if (targetm.calls.function_incoming_arg != targetm.calls.function_arg)
1260 args[i].tail_call_reg
1261 = targetm.calls.function_incoming_arg (args_so_far, mode, type,
1262 argpos < n_named_args);
1264 args[i].tail_call_reg = args[i].reg;
1268 = targetm.calls.arg_partial_bytes (args_so_far, mode, type,
1269 argpos < n_named_args);
1271 args[i].pass_on_stack = targetm.calls.must_pass_in_stack (mode, type);
1273 /* If FUNCTION_ARG returned a (parallel [(expr_list (nil) ...) ...]),
1274 it means that we are to pass this arg in the register(s) designated
1275 by the PARALLEL, but also to pass it in the stack. */
1276 if (args[i].reg && GET_CODE (args[i].reg) == PARALLEL
1277 && XEXP (XVECEXP (args[i].reg, 0, 0), 0) == 0)
1278 args[i].pass_on_stack = 1;
1280 /* If this is an addressable type, we must preallocate the stack
1281 since we must evaluate the object into its final location.
1283 If this is to be passed in both registers and the stack, it is simpler
1285 if (TREE_ADDRESSABLE (type)
1286 || (args[i].pass_on_stack && args[i].reg != 0))
1287 *must_preallocate = 1;
1289 /* Compute the stack-size of this argument. */
1290 if (args[i].reg == 0 || args[i].partial != 0
1291 || reg_parm_stack_space > 0
1292 || args[i].pass_on_stack)
1293 locate_and_pad_parm (mode, type,
1294 #ifdef STACK_PARMS_IN_REG_PARM_AREA
1299 args[i].pass_on_stack ? 0 : args[i].partial,
1300 fndecl, args_size, &args[i].locate);
1301 #ifdef BLOCK_REG_PADDING
1303 /* The argument is passed entirely in registers. See at which
1304 end it should be padded. */
1305 args[i].locate.where_pad =
1306 BLOCK_REG_PADDING (mode, type,
1307 int_size_in_bytes (type) <= UNITS_PER_WORD);
1310 /* Update ARGS_SIZE, the total stack space for args so far. */
1312 args_size->constant += args[i].locate.size.constant;
1313 if (args[i].locate.size.var)
1314 ADD_PARM_SIZE (*args_size, args[i].locate.size.var);
1316 /* Increment ARGS_SO_FAR, which has info about which arg-registers
1317 have been used, etc. */
1319 targetm.calls.function_arg_advance (args_so_far, TYPE_MODE (type),
1320 type, argpos < n_named_args);
1324 /* Update ARGS_SIZE to contain the total size for the argument block.
1325 Return the original constant component of the argument block's size.
1327 REG_PARM_STACK_SPACE holds the number of bytes of stack space reserved
1328 for arguments passed in registers. */
1331 compute_argument_block_size (int reg_parm_stack_space,
1332 struct args_size *args_size,
1333 tree fndecl ATTRIBUTE_UNUSED,
1334 tree fntype ATTRIBUTE_UNUSED,
1335 int preferred_stack_boundary ATTRIBUTE_UNUSED)
1337 int unadjusted_args_size = args_size->constant;
1339 /* For accumulate outgoing args mode we don't need to align, since the frame
1340 will be already aligned. Align to STACK_BOUNDARY in order to prevent
1341 backends from generating misaligned frame sizes. */
1342 if (ACCUMULATE_OUTGOING_ARGS && preferred_stack_boundary > STACK_BOUNDARY)
1343 preferred_stack_boundary = STACK_BOUNDARY;
1345 /* Compute the actual size of the argument block required. The variable
1346 and constant sizes must be combined, the size may have to be rounded,
1347 and there may be a minimum required size. */
1351 args_size->var = ARGS_SIZE_TREE (*args_size);
1352 args_size->constant = 0;
1354 preferred_stack_boundary /= BITS_PER_UNIT;
1355 if (preferred_stack_boundary > 1)
1357 /* We don't handle this case yet. To handle it correctly we have
1358 to add the delta, round and subtract the delta.
1359 Currently no machine description requires this support. */
1360 gcc_assert (!(stack_pointer_delta & (preferred_stack_boundary - 1)));
1361 args_size->var = round_up (args_size->var, preferred_stack_boundary);
1364 if (reg_parm_stack_space > 0)
1367 = size_binop (MAX_EXPR, args_size->var,
1368 ssize_int (reg_parm_stack_space));
1370 /* The area corresponding to register parameters is not to count in
1371 the size of the block we need. So make the adjustment. */
1372 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1374 = size_binop (MINUS_EXPR, args_size->var,
1375 ssize_int (reg_parm_stack_space));
1380 preferred_stack_boundary /= BITS_PER_UNIT;
1381 if (preferred_stack_boundary < 1)
1382 preferred_stack_boundary = 1;
1383 args_size->constant = (((args_size->constant
1384 + stack_pointer_delta
1385 + preferred_stack_boundary - 1)
1386 / preferred_stack_boundary
1387 * preferred_stack_boundary)
1388 - stack_pointer_delta);
1390 args_size->constant = MAX (args_size->constant,
1391 reg_parm_stack_space);
1393 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
1394 args_size->constant -= reg_parm_stack_space;
1396 return unadjusted_args_size;
1399 /* Precompute parameters as needed for a function call.
1401 FLAGS is mask of ECF_* constants.
1403 NUM_ACTUALS is the number of arguments.
1405 ARGS is an array containing information for each argument; this
1406 routine fills in the INITIAL_VALUE and VALUE fields for each
1407 precomputed argument. */
1410 precompute_arguments (int num_actuals, struct arg_data *args)
1414 /* If this is a libcall, then precompute all arguments so that we do not
1415 get extraneous instructions emitted as part of the libcall sequence. */
1417 /* If we preallocated the stack space, and some arguments must be passed
1418 on the stack, then we must precompute any parameter which contains a
1419 function call which will store arguments on the stack.
1420 Otherwise, evaluating the parameter may clobber previous parameters
1421 which have already been stored into the stack. (we have code to avoid
1422 such case by saving the outgoing stack arguments, but it results in
1424 if (!ACCUMULATE_OUTGOING_ARGS)
1427 for (i = 0; i < num_actuals; i++)
1430 enum machine_mode mode;
1432 if (TREE_CODE (args[i].tree_value) != CALL_EXPR)
1435 /* If this is an addressable type, we cannot pre-evaluate it. */
1436 type = TREE_TYPE (args[i].tree_value);
1437 gcc_assert (!TREE_ADDRESSABLE (type));
1439 args[i].initial_value = args[i].value
1440 = expand_normal (args[i].tree_value);
1442 mode = TYPE_MODE (type);
1443 if (mode != args[i].mode)
1445 int unsignedp = args[i].unsignedp;
1447 = convert_modes (args[i].mode, mode,
1448 args[i].value, args[i].unsignedp);
1450 /* CSE will replace this only if it contains args[i].value
1451 pseudo, so convert it down to the declared mode using
1453 if (REG_P (args[i].value)
1454 && GET_MODE_CLASS (args[i].mode) == MODE_INT
1455 && promote_mode (type, mode, &unsignedp) != args[i].mode)
1457 args[i].initial_value
1458 = gen_lowpart_SUBREG (mode, args[i].value);
1459 SUBREG_PROMOTED_VAR_P (args[i].initial_value) = 1;
1460 SUBREG_PROMOTED_UNSIGNED_SET (args[i].initial_value,
1467 /* Given the current state of MUST_PREALLOCATE and information about
1468 arguments to a function call in NUM_ACTUALS, ARGS and ARGS_SIZE,
1469 compute and return the final value for MUST_PREALLOCATE. */
1472 finalize_must_preallocate (int must_preallocate, int num_actuals,
1473 struct arg_data *args, struct args_size *args_size)
1475 /* See if we have or want to preallocate stack space.
1477 If we would have to push a partially-in-regs parm
1478 before other stack parms, preallocate stack space instead.
1480 If the size of some parm is not a multiple of the required stack
1481 alignment, we must preallocate.
1483 If the total size of arguments that would otherwise create a copy in
1484 a temporary (such as a CALL) is more than half the total argument list
1485 size, preallocation is faster.
1487 Another reason to preallocate is if we have a machine (like the m88k)
1488 where stack alignment is required to be maintained between every
1489 pair of insns, not just when the call is made. However, we assume here
1490 that such machines either do not have push insns (and hence preallocation
1491 would occur anyway) or the problem is taken care of with
1494 if (! must_preallocate)
1496 int partial_seen = 0;
1497 int copy_to_evaluate_size = 0;
1500 for (i = 0; i < num_actuals && ! must_preallocate; i++)
1502 if (args[i].partial > 0 && ! args[i].pass_on_stack)
1504 else if (partial_seen && args[i].reg == 0)
1505 must_preallocate = 1;
1507 if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode
1508 && (TREE_CODE (args[i].tree_value) == CALL_EXPR
1509 || TREE_CODE (args[i].tree_value) == TARGET_EXPR
1510 || TREE_CODE (args[i].tree_value) == COND_EXPR
1511 || TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))))
1512 copy_to_evaluate_size
1513 += int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1516 if (copy_to_evaluate_size * 2 >= args_size->constant
1517 && args_size->constant > 0)
1518 must_preallocate = 1;
1520 return must_preallocate;
1523 /* If we preallocated stack space, compute the address of each argument
1524 and store it into the ARGS array.
1526 We need not ensure it is a valid memory address here; it will be
1527 validized when it is used.
1529 ARGBLOCK is an rtx for the address of the outgoing arguments. */
1532 compute_argument_addresses (struct arg_data *args, rtx argblock, int num_actuals)
1536 rtx arg_reg = argblock;
1537 int i, arg_offset = 0;
1539 if (GET_CODE (argblock) == PLUS)
1540 arg_reg = XEXP (argblock, 0), arg_offset = INTVAL (XEXP (argblock, 1));
1542 for (i = 0; i < num_actuals; i++)
1544 rtx offset = ARGS_SIZE_RTX (args[i].locate.offset);
1545 rtx slot_offset = ARGS_SIZE_RTX (args[i].locate.slot_offset);
1547 unsigned int align, boundary;
1548 unsigned int units_on_stack = 0;
1549 enum machine_mode partial_mode = VOIDmode;
1551 /* Skip this parm if it will not be passed on the stack. */
1552 if (! args[i].pass_on_stack
1554 && args[i].partial == 0)
1557 if (CONST_INT_P (offset))
1558 addr = plus_constant (arg_reg, INTVAL (offset));
1560 addr = gen_rtx_PLUS (Pmode, arg_reg, offset);
1562 addr = plus_constant (addr, arg_offset);
1564 if (args[i].partial != 0)
1566 /* Only part of the parameter is being passed on the stack.
1567 Generate a simple memory reference of the correct size. */
1568 units_on_stack = args[i].locate.size.constant;
1569 partial_mode = mode_for_size (units_on_stack * BITS_PER_UNIT,
1571 args[i].stack = gen_rtx_MEM (partial_mode, addr);
1572 set_mem_size (args[i].stack, units_on_stack);
1576 args[i].stack = gen_rtx_MEM (args[i].mode, addr);
1577 set_mem_attributes (args[i].stack,
1578 TREE_TYPE (args[i].tree_value), 1);
1580 align = BITS_PER_UNIT;
1581 boundary = args[i].locate.boundary;
1582 if (args[i].locate.where_pad != downward)
1584 else if (CONST_INT_P (offset))
1586 align = INTVAL (offset) * BITS_PER_UNIT | boundary;
1587 align = align & -align;
1589 set_mem_align (args[i].stack, align);
1591 if (CONST_INT_P (slot_offset))
1592 addr = plus_constant (arg_reg, INTVAL (slot_offset));
1594 addr = gen_rtx_PLUS (Pmode, arg_reg, slot_offset);
1596 addr = plus_constant (addr, arg_offset);
1598 if (args[i].partial != 0)
1600 /* Only part of the parameter is being passed on the stack.
1601 Generate a simple memory reference of the correct size.
1603 args[i].stack_slot = gen_rtx_MEM (partial_mode, addr);
1604 set_mem_size (args[i].stack_slot, units_on_stack);
1608 args[i].stack_slot = gen_rtx_MEM (args[i].mode, addr);
1609 set_mem_attributes (args[i].stack_slot,
1610 TREE_TYPE (args[i].tree_value), 1);
1612 set_mem_align (args[i].stack_slot, args[i].locate.boundary);
1614 /* Function incoming arguments may overlap with sibling call
1615 outgoing arguments and we cannot allow reordering of reads
1616 from function arguments with stores to outgoing arguments
1617 of sibling calls. */
1618 set_mem_alias_set (args[i].stack, 0);
1619 set_mem_alias_set (args[i].stack_slot, 0);
1624 /* Given a FNDECL and EXP, return an rtx suitable for use as a target address
1625 in a call instruction.
1627 FNDECL is the tree node for the target function. For an indirect call
1628 FNDECL will be NULL_TREE.
1630 ADDR is the operand 0 of CALL_EXPR for this call. */
1633 rtx_for_function_call (tree fndecl, tree addr)
1637 /* Get the function to call, in the form of RTL. */
1640 /* If this is the first use of the function, see if we need to
1641 make an external definition for it. */
1642 if (!TREE_USED (fndecl) && fndecl != current_function_decl)
1644 assemble_external (fndecl);
1645 TREE_USED (fndecl) = 1;
1648 /* Get a SYMBOL_REF rtx for the function address. */
1649 funexp = XEXP (DECL_RTL (fndecl), 0);
1652 /* Generate an rtx (probably a pseudo-register) for the address. */
1655 funexp = expand_normal (addr);
1656 pop_temp_slots (); /* FUNEXP can't be BLKmode. */
1661 /* Internal state for internal_arg_pointer_based_exp and its helpers. */
1664 /* Last insn that has been scanned by internal_arg_pointer_based_exp_scan,
1665 or NULL_RTX if none has been scanned yet. */
1667 /* Vector indexed by REGNO - FIRST_PSEUDO_REGISTER, recording if a pseudo is
1668 based on crtl->args.internal_arg_pointer. The element is NULL_RTX if the
1669 pseudo isn't based on it, a CONST_INT offset if the pseudo is based on it
1670 with fixed offset, or PC if this is with variable or unknown offset. */
1671 VEC(rtx, heap) *cache;
1672 } internal_arg_pointer_exp_state;
1674 static rtx internal_arg_pointer_based_exp (rtx, bool);
1676 /* Helper function for internal_arg_pointer_based_exp. Scan insns in
1677 the tail call sequence, starting with first insn that hasn't been
1678 scanned yet, and note for each pseudo on the LHS whether it is based
1679 on crtl->args.internal_arg_pointer or not, and what offset from that
1680 that pointer it has. */
1683 internal_arg_pointer_based_exp_scan (void)
1685 rtx insn, scan_start = internal_arg_pointer_exp_state.scan_start;
1687 if (scan_start == NULL_RTX)
1688 insn = get_insns ();
1690 insn = NEXT_INSN (scan_start);
1694 rtx set = single_set (insn);
1695 if (set && REG_P (SET_DEST (set)) && !HARD_REGISTER_P (SET_DEST (set)))
1698 unsigned int idx = REGNO (SET_DEST (set)) - FIRST_PSEUDO_REGISTER;
1699 /* Punt on pseudos set multiple times. */
1700 if (idx < VEC_length (rtx, internal_arg_pointer_exp_state.cache)
1701 && (VEC_index (rtx, internal_arg_pointer_exp_state.cache, idx)
1705 val = internal_arg_pointer_based_exp (SET_SRC (set), false);
1706 if (val != NULL_RTX)
1708 VEC_safe_grow_cleared (rtx, heap,
1709 internal_arg_pointer_exp_state.cache,
1711 VEC_replace (rtx, internal_arg_pointer_exp_state.cache,
1715 if (NEXT_INSN (insn) == NULL_RTX)
1717 insn = NEXT_INSN (insn);
1720 internal_arg_pointer_exp_state.scan_start = scan_start;
1723 /* Helper function for internal_arg_pointer_based_exp, called through
1724 for_each_rtx. Return 1 if *LOC is a register based on
1725 crtl->args.internal_arg_pointer. Return -1 if *LOC is not based on it
1726 and the subexpressions need not be examined. Otherwise return 0. */
1729 internal_arg_pointer_based_exp_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
1731 if (REG_P (*loc) && internal_arg_pointer_based_exp (*loc, false) != NULL_RTX)
1738 /* Compute whether RTL is based on crtl->args.internal_arg_pointer. Return
1739 NULL_RTX if RTL isn't based on it, a CONST_INT offset if RTL is based on
1740 it with fixed offset, or PC if this is with variable or unknown offset.
1741 TOPLEVEL is true if the function is invoked at the topmost level. */
1744 internal_arg_pointer_based_exp (rtx rtl, bool toplevel)
1746 if (CONSTANT_P (rtl))
1749 if (rtl == crtl->args.internal_arg_pointer)
1752 if (REG_P (rtl) && HARD_REGISTER_P (rtl))
1755 if (GET_CODE (rtl) == PLUS && CONST_INT_P (XEXP (rtl, 1)))
1757 rtx val = internal_arg_pointer_based_exp (XEXP (rtl, 0), toplevel);
1758 if (val == NULL_RTX || val == pc_rtx)
1760 return plus_constant (val, INTVAL (XEXP (rtl, 1)));
1763 /* When called at the topmost level, scan pseudo assignments in between the
1764 last scanned instruction in the tail call sequence and the latest insn
1765 in that sequence. */
1767 internal_arg_pointer_based_exp_scan ();
1771 unsigned int idx = REGNO (rtl) - FIRST_PSEUDO_REGISTER;
1772 if (idx < VEC_length (rtx, internal_arg_pointer_exp_state.cache))
1773 return VEC_index (rtx, internal_arg_pointer_exp_state.cache, idx);
1778 if (for_each_rtx (&rtl, internal_arg_pointer_based_exp_1, NULL))
1784 /* Return true if and only if SIZE storage units (usually bytes)
1785 starting from address ADDR overlap with already clobbered argument
1786 area. This function is used to determine if we should give up a
1790 mem_overlaps_already_clobbered_arg_p (rtx addr, unsigned HOST_WIDE_INT size)
1795 if (sbitmap_empty_p (stored_args_map))
1797 val = internal_arg_pointer_based_exp (addr, true);
1798 if (val == NULL_RTX)
1800 else if (val == pc_rtx)
1805 #ifdef ARGS_GROW_DOWNWARD
1810 unsigned HOST_WIDE_INT k;
1812 for (k = 0; k < size; k++)
1813 if (i + k < stored_args_map->n_bits
1814 && TEST_BIT (stored_args_map, i + k))
1821 /* Do the register loads required for any wholly-register parms or any
1822 parms which are passed both on the stack and in a register. Their
1823 expressions were already evaluated.
1825 Mark all register-parms as living through the call, putting these USE
1826 insns in the CALL_INSN_FUNCTION_USAGE field.
1828 When IS_SIBCALL, perform the check_sibcall_argument_overlap
1829 checking, setting *SIBCALL_FAILURE if appropriate. */
1832 load_register_parameters (struct arg_data *args, int num_actuals,
1833 rtx *call_fusage, int flags, int is_sibcall,
1834 int *sibcall_failure)
1838 for (i = 0; i < num_actuals; i++)
1840 rtx reg = ((flags & ECF_SIBCALL)
1841 ? args[i].tail_call_reg : args[i].reg);
1844 int partial = args[i].partial;
1847 rtx before_arg = get_last_insn ();
1848 /* Set non-negative if we must move a word at a time, even if
1849 just one word (e.g, partial == 4 && mode == DFmode). Set
1850 to -1 if we just use a normal move insn. This value can be
1851 zero if the argument is a zero size structure. */
1853 if (GET_CODE (reg) == PARALLEL)
1857 gcc_assert (partial % UNITS_PER_WORD == 0);
1858 nregs = partial / UNITS_PER_WORD;
1860 else if (TYPE_MODE (TREE_TYPE (args[i].tree_value)) == BLKmode)
1862 size = int_size_in_bytes (TREE_TYPE (args[i].tree_value));
1863 nregs = (size + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD;
1866 size = GET_MODE_SIZE (args[i].mode);
1868 /* Handle calls that pass values in multiple non-contiguous
1869 locations. The Irix 6 ABI has examples of this. */
1871 if (GET_CODE (reg) == PARALLEL)
1872 emit_group_move (reg, args[i].parallel_value);
1874 /* If simple case, just do move. If normal partial, store_one_arg
1875 has already loaded the register for us. In all other cases,
1876 load the register(s) from memory. */
1878 else if (nregs == -1)
1880 emit_move_insn (reg, args[i].value);
1881 #ifdef BLOCK_REG_PADDING
1882 /* Handle case where we have a value that needs shifting
1883 up to the msb. eg. a QImode value and we're padding
1884 upward on a BYTES_BIG_ENDIAN machine. */
1885 if (size < UNITS_PER_WORD
1886 && (args[i].locate.where_pad
1887 == (BYTES_BIG_ENDIAN ? upward : downward)))
1890 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1892 /* Assigning REG here rather than a temp makes CALL_FUSAGE
1893 report the whole reg as used. Strictly speaking, the
1894 call only uses SIZE bytes at the msb end, but it doesn't
1895 seem worth generating rtl to say that. */
1896 reg = gen_rtx_REG (word_mode, REGNO (reg));
1897 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
1899 emit_move_insn (reg, x);
1904 /* If we have pre-computed the values to put in the registers in
1905 the case of non-aligned structures, copy them in now. */
1907 else if (args[i].n_aligned_regs != 0)
1908 for (j = 0; j < args[i].n_aligned_regs; j++)
1909 emit_move_insn (gen_rtx_REG (word_mode, REGNO (reg) + j),
1910 args[i].aligned_regs[j]);
1912 else if (partial == 0 || args[i].pass_on_stack)
1914 rtx mem = validize_mem (args[i].value);
1916 /* Check for overlap with already clobbered argument area,
1917 providing that this has non-zero size. */
1920 || mem_overlaps_already_clobbered_arg_p
1921 (XEXP (args[i].value, 0), size)))
1922 *sibcall_failure = 1;
1924 /* Handle a BLKmode that needs shifting. */
1925 if (nregs == 1 && size < UNITS_PER_WORD
1926 #ifdef BLOCK_REG_PADDING
1927 && args[i].locate.where_pad == downward
1933 rtx tem = operand_subword_force (mem, 0, args[i].mode);
1934 rtx ri = gen_rtx_REG (word_mode, REGNO (reg));
1935 rtx x = gen_reg_rtx (word_mode);
1936 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
1937 enum tree_code dir = BYTES_BIG_ENDIAN ? RSHIFT_EXPR
1940 emit_move_insn (x, tem);
1941 x = expand_shift (dir, word_mode, x, shift, ri, 1);
1943 emit_move_insn (ri, x);
1946 move_block_to_reg (REGNO (reg), mem, nregs, args[i].mode);
1949 /* When a parameter is a block, and perhaps in other cases, it is
1950 possible that it did a load from an argument slot that was
1951 already clobbered. */
1953 && check_sibcall_argument_overlap (before_arg, &args[i], 0))
1954 *sibcall_failure = 1;
1956 /* Handle calls that pass values in multiple non-contiguous
1957 locations. The Irix 6 ABI has examples of this. */
1958 if (GET_CODE (reg) == PARALLEL)
1959 use_group_regs (call_fusage, reg);
1960 else if (nregs == -1)
1961 use_reg_mode (call_fusage, reg,
1962 TYPE_MODE (TREE_TYPE (args[i].tree_value)));
1964 use_regs (call_fusage, REGNO (reg), nregs);
1969 /* We need to pop PENDING_STACK_ADJUST bytes. But, if the arguments
1970 wouldn't fill up an even multiple of PREFERRED_UNIT_STACK_BOUNDARY
1971 bytes, then we would need to push some additional bytes to pad the
1972 arguments. So, we compute an adjust to the stack pointer for an
1973 amount that will leave the stack under-aligned by UNADJUSTED_ARGS_SIZE
1974 bytes. Then, when the arguments are pushed the stack will be perfectly
1975 aligned. ARGS_SIZE->CONSTANT is set to the number of bytes that should
1976 be popped after the call. Returns the adjustment. */
1979 combine_pending_stack_adjustment_and_call (int unadjusted_args_size,
1980 struct args_size *args_size,
1981 unsigned int preferred_unit_stack_boundary)
1983 /* The number of bytes to pop so that the stack will be
1984 under-aligned by UNADJUSTED_ARGS_SIZE bytes. */
1985 HOST_WIDE_INT adjustment;
1986 /* The alignment of the stack after the arguments are pushed, if we
1987 just pushed the arguments without adjust the stack here. */
1988 unsigned HOST_WIDE_INT unadjusted_alignment;
1990 unadjusted_alignment
1991 = ((stack_pointer_delta + unadjusted_args_size)
1992 % preferred_unit_stack_boundary);
1994 /* We want to get rid of as many of the PENDING_STACK_ADJUST bytes
1995 as possible -- leaving just enough left to cancel out the
1996 UNADJUSTED_ALIGNMENT. In other words, we want to ensure that the
1997 PENDING_STACK_ADJUST is non-negative, and congruent to
1998 -UNADJUSTED_ALIGNMENT modulo the PREFERRED_UNIT_STACK_BOUNDARY. */
2000 /* Begin by trying to pop all the bytes. */
2001 unadjusted_alignment
2002 = (unadjusted_alignment
2003 - (pending_stack_adjust % preferred_unit_stack_boundary));
2004 adjustment = pending_stack_adjust;
2005 /* Push enough additional bytes that the stack will be aligned
2006 after the arguments are pushed. */
2007 if (preferred_unit_stack_boundary > 1)
2009 if (unadjusted_alignment > 0)
2010 adjustment -= preferred_unit_stack_boundary - unadjusted_alignment;
2012 adjustment += unadjusted_alignment;
2015 /* Now, sets ARGS_SIZE->CONSTANT so that we pop the right number of
2016 bytes after the call. The right number is the entire
2017 PENDING_STACK_ADJUST less our ADJUSTMENT plus the amount required
2018 by the arguments in the first place. */
2020 = pending_stack_adjust - adjustment + unadjusted_args_size;
2025 /* Scan X expression if it does not dereference any argument slots
2026 we already clobbered by tail call arguments (as noted in stored_args_map
2028 Return nonzero if X expression dereferences such argument slots,
2032 check_sibcall_argument_overlap_1 (rtx x)
2041 code = GET_CODE (x);
2043 /* We need not check the operands of the CALL expression itself. */
2048 return mem_overlaps_already_clobbered_arg_p (XEXP (x, 0),
2049 GET_MODE_SIZE (GET_MODE (x)));
2051 /* Scan all subexpressions. */
2052 fmt = GET_RTX_FORMAT (code);
2053 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
2057 if (check_sibcall_argument_overlap_1 (XEXP (x, i)))
2060 else if (*fmt == 'E')
2062 for (j = 0; j < XVECLEN (x, i); j++)
2063 if (check_sibcall_argument_overlap_1 (XVECEXP (x, i, j)))
2070 /* Scan sequence after INSN if it does not dereference any argument slots
2071 we already clobbered by tail call arguments (as noted in stored_args_map
2072 bitmap). If MARK_STORED_ARGS_MAP, add stack slots for ARG to
2073 stored_args_map bitmap afterwards (when ARG is a register MARK_STORED_ARGS_MAP
2074 should be 0). Return nonzero if sequence after INSN dereferences such argument
2075 slots, zero otherwise. */
2078 check_sibcall_argument_overlap (rtx insn, struct arg_data *arg, int mark_stored_args_map)
2082 if (insn == NULL_RTX)
2083 insn = get_insns ();
2085 insn = NEXT_INSN (insn);
2087 for (; insn; insn = NEXT_INSN (insn))
2089 && check_sibcall_argument_overlap_1 (PATTERN (insn)))
2092 if (mark_stored_args_map)
2094 #ifdef ARGS_GROW_DOWNWARD
2095 low = -arg->locate.slot_offset.constant - arg->locate.size.constant;
2097 low = arg->locate.slot_offset.constant;
2100 for (high = low + arg->locate.size.constant; low < high; low++)
2101 SET_BIT (stored_args_map, low);
2103 return insn != NULL_RTX;
2106 /* Given that a function returns a value of mode MODE at the most
2107 significant end of hard register VALUE, shift VALUE left or right
2108 as specified by LEFT_P. Return true if some action was needed. */
2111 shift_return_value (enum machine_mode mode, bool left_p, rtx value)
2113 HOST_WIDE_INT shift;
2115 gcc_assert (REG_P (value) && HARD_REGISTER_P (value));
2116 shift = GET_MODE_BITSIZE (GET_MODE (value)) - GET_MODE_BITSIZE (mode);
2120 /* Use ashr rather than lshr for right shifts. This is for the benefit
2121 of the MIPS port, which requires SImode values to be sign-extended
2122 when stored in 64-bit registers. */
2123 if (!force_expand_binop (GET_MODE (value), left_p ? ashl_optab : ashr_optab,
2124 value, GEN_INT (shift), value, 1, OPTAB_WIDEN))
2129 /* If X is a likely-spilled register value, copy it to a pseudo
2130 register and return that register. Return X otherwise. */
2133 avoid_likely_spilled_reg (rtx x)
2138 && HARD_REGISTER_P (x)
2139 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (x))))
2141 /* Make sure that we generate a REG rather than a CONCAT.
2142 Moves into CONCATs can need nontrivial instructions,
2143 and the whole point of this function is to avoid
2144 using the hard register directly in such a situation. */
2145 generating_concat_p = 0;
2146 new_rtx = gen_reg_rtx (GET_MODE (x));
2147 generating_concat_p = 1;
2148 emit_move_insn (new_rtx, x);
2154 /* Generate all the code for a CALL_EXPR exp
2155 and return an rtx for its value.
2156 Store the value in TARGET (specified as an rtx) if convenient.
2157 If the value is stored in TARGET then TARGET is returned.
2158 If IGNORE is nonzero, then we ignore the value of the function call. */
2161 expand_call (tree exp, rtx target, int ignore)
2163 /* Nonzero if we are currently expanding a call. */
2164 static int currently_expanding_call = 0;
2166 /* RTX for the function to be called. */
2168 /* Sequence of insns to perform a normal "call". */
2169 rtx normal_call_insns = NULL_RTX;
2170 /* Sequence of insns to perform a tail "call". */
2171 rtx tail_call_insns = NULL_RTX;
2172 /* Data type of the function. */
2174 tree type_arg_types;
2176 /* Declaration of the function being called,
2177 or 0 if the function is computed (not known by name). */
2179 /* The type of the function being called. */
2181 bool try_tail_call = CALL_EXPR_TAILCALL (exp);
2184 /* Register in which non-BLKmode value will be returned,
2185 or 0 if no value or if value is BLKmode. */
2187 /* Address where we should return a BLKmode value;
2188 0 if value not BLKmode. */
2189 rtx structure_value_addr = 0;
2190 /* Nonzero if that address is being passed by treating it as
2191 an extra, implicit first parameter. Otherwise,
2192 it is passed by being copied directly into struct_value_rtx. */
2193 int structure_value_addr_parm = 0;
2194 /* Holds the value of implicit argument for the struct value. */
2195 tree structure_value_addr_value = NULL_TREE;
2196 /* Size of aggregate value wanted, or zero if none wanted
2197 or if we are using the non-reentrant PCC calling convention
2198 or expecting the value in registers. */
2199 HOST_WIDE_INT struct_value_size = 0;
2200 /* Nonzero if called function returns an aggregate in memory PCC style,
2201 by returning the address of where to find it. */
2202 int pcc_struct_value = 0;
2203 rtx struct_value = 0;
2205 /* Number of actual parameters in this call, including struct value addr. */
2207 /* Number of named args. Args after this are anonymous ones
2208 and they must all go on the stack. */
2210 /* Number of complex actual arguments that need to be split. */
2211 int num_complex_actuals = 0;
2213 /* Vector of information about each argument.
2214 Arguments are numbered in the order they will be pushed,
2215 not the order they are written. */
2216 struct arg_data *args;
2218 /* Total size in bytes of all the stack-parms scanned so far. */
2219 struct args_size args_size;
2220 struct args_size adjusted_args_size;
2221 /* Size of arguments before any adjustments (such as rounding). */
2222 int unadjusted_args_size;
2223 /* Data on reg parms scanned so far. */
2224 CUMULATIVE_ARGS args_so_far_v;
2225 cumulative_args_t args_so_far;
2226 /* Nonzero if a reg parm has been scanned. */
2228 /* Nonzero if this is an indirect function call. */
2230 /* Nonzero if we must avoid push-insns in the args for this call.
2231 If stack space is allocated for register parameters, but not by the
2232 caller, then it is preallocated in the fixed part of the stack frame.
2233 So the entire argument block must then be preallocated (i.e., we
2234 ignore PUSH_ROUNDING in that case). */
2236 int must_preallocate = !PUSH_ARGS;
2238 /* Size of the stack reserved for parameter registers. */
2239 int reg_parm_stack_space = 0;
2241 /* Address of space preallocated for stack parms
2242 (on machines that lack push insns), or 0 if space not preallocated. */
2245 /* Mask of ECF_ flags. */
2247 #ifdef REG_PARM_STACK_SPACE
2248 /* Define the boundary of the register parm stack space that needs to be
2250 int low_to_save, high_to_save;
2251 rtx save_area = 0; /* Place that it is saved */
2254 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
2255 char *initial_stack_usage_map = stack_usage_map;
2256 char *stack_usage_map_buf = NULL;
2258 int old_stack_allocated;
2260 /* State variables to track stack modifications. */
2261 rtx old_stack_level = 0;
2262 int old_stack_arg_under_construction = 0;
2263 int old_pending_adj = 0;
2264 int old_inhibit_defer_pop = inhibit_defer_pop;
2266 /* Some stack pointer alterations we make are performed via
2267 allocate_dynamic_stack_space. This modifies the stack_pointer_delta,
2268 which we then also need to save/restore along the way. */
2269 int old_stack_pointer_delta = 0;
2272 tree addr = CALL_EXPR_FN (exp);
2274 /* The alignment of the stack, in bits. */
2275 unsigned HOST_WIDE_INT preferred_stack_boundary;
2276 /* The alignment of the stack, in bytes. */
2277 unsigned HOST_WIDE_INT preferred_unit_stack_boundary;
2278 /* The static chain value to use for this call. */
2279 rtx static_chain_value;
2280 /* See if this is "nothrow" function call. */
2281 if (TREE_NOTHROW (exp))
2282 flags |= ECF_NOTHROW;
2284 /* See if we can find a DECL-node for the actual function, and get the
2285 function attributes (flags) from the function decl or type node. */
2286 fndecl = get_callee_fndecl (exp);
2289 fntype = TREE_TYPE (fndecl);
2290 flags |= flags_from_decl_or_type (fndecl);
2294 fntype = TREE_TYPE (TREE_TYPE (addr));
2295 flags |= flags_from_decl_or_type (fntype);
2297 rettype = TREE_TYPE (exp);
2299 struct_value = targetm.calls.struct_value_rtx (fntype, 0);
2301 /* Warn if this value is an aggregate type,
2302 regardless of which calling convention we are using for it. */
2303 if (AGGREGATE_TYPE_P (rettype))
2304 warning (OPT_Waggregate_return, "function call has aggregate value");
2306 /* If the result of a non looping pure or const function call is
2307 ignored (or void), and none of its arguments are volatile, we can
2308 avoid expanding the call and just evaluate the arguments for
2310 if ((flags & (ECF_CONST | ECF_PURE))
2311 && (!(flags & ECF_LOOPING_CONST_OR_PURE))
2312 && (ignore || target == const0_rtx
2313 || TYPE_MODE (rettype) == VOIDmode))
2315 bool volatilep = false;
2317 call_expr_arg_iterator iter;
2319 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2320 if (TREE_THIS_VOLATILE (arg))
2328 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2329 expand_expr (arg, const0_rtx, VOIDmode, EXPAND_NORMAL);
2334 #ifdef REG_PARM_STACK_SPACE
2335 reg_parm_stack_space = REG_PARM_STACK_SPACE (!fndecl ? fntype : fndecl);
2338 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
2339 && reg_parm_stack_space > 0 && PUSH_ARGS)
2340 must_preallocate = 1;
2342 /* Set up a place to return a structure. */
2344 /* Cater to broken compilers. */
2345 if (aggregate_value_p (exp, fntype))
2347 /* This call returns a big structure. */
2348 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
2350 #ifdef PCC_STATIC_STRUCT_RETURN
2352 pcc_struct_value = 1;
2354 #else /* not PCC_STATIC_STRUCT_RETURN */
2356 struct_value_size = int_size_in_bytes (rettype);
2358 if (target && MEM_P (target) && CALL_EXPR_RETURN_SLOT_OPT (exp))
2359 structure_value_addr = XEXP (target, 0);
2362 /* For variable-sized objects, we must be called with a target
2363 specified. If we were to allocate space on the stack here,
2364 we would have no way of knowing when to free it. */
2365 rtx d = assign_temp (rettype, 0, 1, 1);
2367 mark_temp_addr_taken (d);
2368 structure_value_addr = XEXP (d, 0);
2372 #endif /* not PCC_STATIC_STRUCT_RETURN */
2375 /* Figure out the amount to which the stack should be aligned. */
2376 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
2379 struct cgraph_rtl_info *i = cgraph_rtl_info (fndecl);
2380 /* Without automatic stack alignment, we can't increase preferred
2381 stack boundary. With automatic stack alignment, it is
2382 unnecessary since unless we can guarantee that all callers will
2383 align the outgoing stack properly, callee has to align its
2386 && i->preferred_incoming_stack_boundary
2387 && i->preferred_incoming_stack_boundary < preferred_stack_boundary)
2388 preferred_stack_boundary = i->preferred_incoming_stack_boundary;
2391 /* Operand 0 is a pointer-to-function; get the type of the function. */
2392 funtype = TREE_TYPE (addr);
2393 gcc_assert (POINTER_TYPE_P (funtype));
2394 funtype = TREE_TYPE (funtype);
2396 /* Count whether there are actual complex arguments that need to be split
2397 into their real and imaginary parts. Munge the type_arg_types
2398 appropriately here as well. */
2399 if (targetm.calls.split_complex_arg)
2401 call_expr_arg_iterator iter;
2403 FOR_EACH_CALL_EXPR_ARG (arg, iter, exp)
2405 tree type = TREE_TYPE (arg);
2406 if (type && TREE_CODE (type) == COMPLEX_TYPE
2407 && targetm.calls.split_complex_arg (type))
2408 num_complex_actuals++;
2410 type_arg_types = split_complex_types (TYPE_ARG_TYPES (funtype));
2413 type_arg_types = TYPE_ARG_TYPES (funtype);
2415 if (flags & ECF_MAY_BE_ALLOCA)
2416 cfun->calls_alloca = 1;
2418 /* If struct_value_rtx is 0, it means pass the address
2419 as if it were an extra parameter. Put the argument expression
2420 in structure_value_addr_value. */
2421 if (structure_value_addr && struct_value == 0)
2423 /* If structure_value_addr is a REG other than
2424 virtual_outgoing_args_rtx, we can use always use it. If it
2425 is not a REG, we must always copy it into a register.
2426 If it is virtual_outgoing_args_rtx, we must copy it to another
2427 register in some cases. */
2428 rtx temp = (!REG_P (structure_value_addr)
2429 || (ACCUMULATE_OUTGOING_ARGS
2430 && stack_arg_under_construction
2431 && structure_value_addr == virtual_outgoing_args_rtx)
2432 ? copy_addr_to_reg (convert_memory_address
2433 (Pmode, structure_value_addr))
2434 : structure_value_addr);
2436 structure_value_addr_value =
2437 make_tree (build_pointer_type (TREE_TYPE (funtype)), temp);
2438 structure_value_addr_parm = 1;
2441 /* Count the arguments and set NUM_ACTUALS. */
2443 call_expr_nargs (exp) + num_complex_actuals + structure_value_addr_parm;
2445 /* Compute number of named args.
2446 First, do a raw count of the args for INIT_CUMULATIVE_ARGS. */
2448 if (type_arg_types != 0)
2450 = (list_length (type_arg_types)
2451 /* Count the struct value address, if it is passed as a parm. */
2452 + structure_value_addr_parm);
2454 /* If we know nothing, treat all args as named. */
2455 n_named_args = num_actuals;
2457 /* Start updating where the next arg would go.
2459 On some machines (such as the PA) indirect calls have a different
2460 calling convention than normal calls. The fourth argument in
2461 INIT_CUMULATIVE_ARGS tells the backend if this is an indirect call
2463 INIT_CUMULATIVE_ARGS (args_so_far_v, funtype, NULL_RTX, fndecl, n_named_args);
2464 args_so_far = pack_cumulative_args (&args_so_far_v);
2466 /* Now possibly adjust the number of named args.
2467 Normally, don't include the last named arg if anonymous args follow.
2468 We do include the last named arg if
2469 targetm.calls.strict_argument_naming() returns nonzero.
2470 (If no anonymous args follow, the result of list_length is actually
2471 one too large. This is harmless.)
2473 If targetm.calls.pretend_outgoing_varargs_named() returns
2474 nonzero, and targetm.calls.strict_argument_naming() returns zero,
2475 this machine will be able to place unnamed args that were passed
2476 in registers into the stack. So treat all args as named. This
2477 allows the insns emitting for a specific argument list to be
2478 independent of the function declaration.
2480 If targetm.calls.pretend_outgoing_varargs_named() returns zero,
2481 we do not have any reliable way to pass unnamed args in
2482 registers, so we must force them into memory. */
2484 if (type_arg_types != 0
2485 && targetm.calls.strict_argument_naming (args_so_far))
2487 else if (type_arg_types != 0
2488 && ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
2489 /* Don't include the last named arg. */
2492 /* Treat all args as named. */
2493 n_named_args = num_actuals;
2495 /* Make a vector to hold all the information about each arg. */
2496 args = XALLOCAVEC (struct arg_data, num_actuals);
2497 memset (args, 0, num_actuals * sizeof (struct arg_data));
2499 /* Build up entries in the ARGS array, compute the size of the
2500 arguments into ARGS_SIZE, etc. */
2501 initialize_argument_information (num_actuals, args, &args_size,
2503 structure_value_addr_value, fndecl, fntype,
2504 args_so_far, reg_parm_stack_space,
2505 &old_stack_level, &old_pending_adj,
2506 &must_preallocate, &flags,
2507 &try_tail_call, CALL_FROM_THUNK_P (exp));
2510 must_preallocate = 1;
2512 /* Now make final decision about preallocating stack space. */
2513 must_preallocate = finalize_must_preallocate (must_preallocate,
2517 /* If the structure value address will reference the stack pointer, we
2518 must stabilize it. We don't need to do this if we know that we are
2519 not going to adjust the stack pointer in processing this call. */
2521 if (structure_value_addr
2522 && (reg_mentioned_p (virtual_stack_dynamic_rtx, structure_value_addr)
2523 || reg_mentioned_p (virtual_outgoing_args_rtx,
2524 structure_value_addr))
2526 || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
2527 structure_value_addr = copy_to_reg (structure_value_addr);
2529 /* Tail calls can make things harder to debug, and we've traditionally
2530 pushed these optimizations into -O2. Don't try if we're already
2531 expanding a call, as that means we're an argument. Don't try if
2532 there's cleanups, as we know there's code to follow the call. */
2534 if (currently_expanding_call++ != 0
2535 || !flag_optimize_sibling_calls
2537 || dbg_cnt (tail_call) == false)
2540 /* Rest of purposes for tail call optimizations to fail. */
2542 #ifdef HAVE_sibcall_epilogue
2543 !HAVE_sibcall_epilogue
2548 /* Doing sibling call optimization needs some work, since
2549 structure_value_addr can be allocated on the stack.
2550 It does not seem worth the effort since few optimizable
2551 sibling calls will return a structure. */
2552 || structure_value_addr != NULL_RTX
2553 #ifdef REG_PARM_STACK_SPACE
2554 /* If outgoing reg parm stack space changes, we can not do sibcall. */
2555 || (OUTGOING_REG_PARM_STACK_SPACE (funtype)
2556 != OUTGOING_REG_PARM_STACK_SPACE (TREE_TYPE (current_function_decl)))
2557 || (reg_parm_stack_space != REG_PARM_STACK_SPACE (fndecl))
2559 /* Check whether the target is able to optimize the call
2561 || !targetm.function_ok_for_sibcall (fndecl, exp)
2562 /* Functions that do not return exactly once may not be sibcall
2564 || (flags & (ECF_RETURNS_TWICE | ECF_NORETURN))
2565 || TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (addr)))
2566 /* If the called function is nested in the current one, it might access
2567 some of the caller's arguments, but could clobber them beforehand if
2568 the argument areas are shared. */
2569 || (fndecl && decl_function_context (fndecl) == current_function_decl)
2570 /* If this function requires more stack slots than the current
2571 function, we cannot change it into a sibling call.
2572 crtl->args.pretend_args_size is not part of the
2573 stack allocated by our caller. */
2574 || args_size.constant > (crtl->args.size
2575 - crtl->args.pretend_args_size)
2576 /* If the callee pops its own arguments, then it must pop exactly
2577 the same number of arguments as the current function. */
2578 || (targetm.calls.return_pops_args (fndecl, funtype, args_size.constant)
2579 != targetm.calls.return_pops_args (current_function_decl,
2580 TREE_TYPE (current_function_decl),
2582 || !lang_hooks.decls.ok_for_sibcall (fndecl))
2585 /* Check if caller and callee disagree in promotion of function
2589 enum machine_mode caller_mode, caller_promoted_mode;
2590 enum machine_mode callee_mode, callee_promoted_mode;
2591 int caller_unsignedp, callee_unsignedp;
2592 tree caller_res = DECL_RESULT (current_function_decl);
2594 caller_unsignedp = TYPE_UNSIGNED (TREE_TYPE (caller_res));
2595 caller_mode = DECL_MODE (caller_res);
2596 callee_unsignedp = TYPE_UNSIGNED (TREE_TYPE (funtype));
2597 callee_mode = TYPE_MODE (TREE_TYPE (funtype));
2598 caller_promoted_mode
2599 = promote_function_mode (TREE_TYPE (caller_res), caller_mode,
2601 TREE_TYPE (current_function_decl), 1);
2602 callee_promoted_mode
2603 = promote_function_mode (TREE_TYPE (funtype), callee_mode,
2606 if (caller_mode != VOIDmode
2607 && (caller_promoted_mode != callee_promoted_mode
2608 || ((caller_mode != caller_promoted_mode
2609 || callee_mode != callee_promoted_mode)
2610 && (caller_unsignedp != callee_unsignedp
2611 || GET_MODE_BITSIZE (caller_mode)
2612 < GET_MODE_BITSIZE (callee_mode)))))
2616 /* Ensure current function's preferred stack boundary is at least
2617 what we need. Stack alignment may also increase preferred stack
2619 if (crtl->preferred_stack_boundary < preferred_stack_boundary)
2620 crtl->preferred_stack_boundary = preferred_stack_boundary;
2622 preferred_stack_boundary = crtl->preferred_stack_boundary;
2624 preferred_unit_stack_boundary = preferred_stack_boundary / BITS_PER_UNIT;
2626 /* We want to make two insn chains; one for a sibling call, the other
2627 for a normal call. We will select one of the two chains after
2628 initial RTL generation is complete. */
2629 for (pass = try_tail_call ? 0 : 1; pass < 2; pass++)
2631 int sibcall_failure = 0;
2632 /* We want to emit any pending stack adjustments before the tail
2633 recursion "call". That way we know any adjustment after the tail
2634 recursion call can be ignored if we indeed use the tail
2636 int save_pending_stack_adjust = 0;
2637 int save_stack_pointer_delta = 0;
2639 rtx before_call, next_arg_reg, after_args;
2643 /* State variables we need to save and restore between
2645 save_pending_stack_adjust = pending_stack_adjust;
2646 save_stack_pointer_delta = stack_pointer_delta;
2649 flags &= ~ECF_SIBCALL;
2651 flags |= ECF_SIBCALL;
2653 /* Other state variables that we must reinitialize each time
2654 through the loop (that are not initialized by the loop itself). */
2658 /* Start a new sequence for the normal call case.
2660 From this point on, if the sibling call fails, we want to set
2661 sibcall_failure instead of continuing the loop. */
2664 /* Don't let pending stack adjusts add up to too much.
2665 Also, do all pending adjustments now if there is any chance
2666 this might be a call to alloca or if we are expanding a sibling
2668 Also do the adjustments before a throwing call, otherwise
2669 exception handling can fail; PR 19225. */
2670 if (pending_stack_adjust >= 32
2671 || (pending_stack_adjust > 0
2672 && (flags & ECF_MAY_BE_ALLOCA))
2673 || (pending_stack_adjust > 0
2674 && flag_exceptions && !(flags & ECF_NOTHROW))
2676 do_pending_stack_adjust ();
2678 /* Precompute any arguments as needed. */
2680 precompute_arguments (num_actuals, args);
2682 /* Now we are about to start emitting insns that can be deleted
2683 if a libcall is deleted. */
2684 if (pass && (flags & ECF_MALLOC))
2687 if (pass == 0 && crtl->stack_protect_guard)
2688 stack_protect_epilogue ();
2690 adjusted_args_size = args_size;
2691 /* Compute the actual size of the argument block required. The variable
2692 and constant sizes must be combined, the size may have to be rounded,
2693 and there may be a minimum required size. When generating a sibcall
2694 pattern, do not round up, since we'll be re-using whatever space our
2696 unadjusted_args_size
2697 = compute_argument_block_size (reg_parm_stack_space,
2698 &adjusted_args_size,
2701 : preferred_stack_boundary));
2703 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
2705 /* The argument block when performing a sibling call is the
2706 incoming argument block. */
2709 argblock = crtl->args.internal_arg_pointer;
2711 #ifdef STACK_GROWS_DOWNWARD
2712 = plus_constant (argblock, crtl->args.pretend_args_size);
2714 = plus_constant (argblock, -crtl->args.pretend_args_size);
2716 stored_args_map = sbitmap_alloc (args_size.constant);
2717 sbitmap_zero (stored_args_map);
2720 /* If we have no actual push instructions, or shouldn't use them,
2721 make space for all args right now. */
2722 else if (adjusted_args_size.var != 0)
2724 if (old_stack_level == 0)
2726 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2727 old_stack_pointer_delta = stack_pointer_delta;
2728 old_pending_adj = pending_stack_adjust;
2729 pending_stack_adjust = 0;
2730 /* stack_arg_under_construction says whether a stack arg is
2731 being constructed at the old stack level. Pushing the stack
2732 gets a clean outgoing argument block. */
2733 old_stack_arg_under_construction = stack_arg_under_construction;
2734 stack_arg_under_construction = 0;
2736 argblock = push_block (ARGS_SIZE_RTX (adjusted_args_size), 0, 0);
2737 if (flag_stack_usage_info)
2738 current_function_has_unbounded_dynamic_stack_size = 1;
2742 /* Note that we must go through the motions of allocating an argument
2743 block even if the size is zero because we may be storing args
2744 in the area reserved for register arguments, which may be part of
2747 int needed = adjusted_args_size.constant;
2749 /* Store the maximum argument space used. It will be pushed by
2750 the prologue (if ACCUMULATE_OUTGOING_ARGS, or stack overflow
2753 if (needed > crtl->outgoing_args_size)
2754 crtl->outgoing_args_size = needed;
2756 if (must_preallocate)
2758 if (ACCUMULATE_OUTGOING_ARGS)
2760 /* Since the stack pointer will never be pushed, it is
2761 possible for the evaluation of a parm to clobber
2762 something we have already written to the stack.
2763 Since most function calls on RISC machines do not use
2764 the stack, this is uncommon, but must work correctly.
2766 Therefore, we save any area of the stack that was already
2767 written and that we are using. Here we set up to do this
2768 by making a new stack usage map from the old one. The
2769 actual save will be done by store_one_arg.
2771 Another approach might be to try to reorder the argument
2772 evaluations to avoid this conflicting stack usage. */
2774 /* Since we will be writing into the entire argument area,
2775 the map must be allocated for its entire size, not just
2776 the part that is the responsibility of the caller. */
2777 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
2778 needed += reg_parm_stack_space;
2780 #ifdef ARGS_GROW_DOWNWARD
2781 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2784 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
2787 free (stack_usage_map_buf);
2788 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
2789 stack_usage_map = stack_usage_map_buf;
2791 if (initial_highest_arg_in_use)
2792 memcpy (stack_usage_map, initial_stack_usage_map,
2793 initial_highest_arg_in_use);
2795 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
2796 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
2797 (highest_outgoing_arg_in_use
2798 - initial_highest_arg_in_use));
2801 /* The address of the outgoing argument list must not be
2802 copied to a register here, because argblock would be left
2803 pointing to the wrong place after the call to
2804 allocate_dynamic_stack_space below. */
2806 argblock = virtual_outgoing_args_rtx;
2810 if (inhibit_defer_pop == 0)
2812 /* Try to reuse some or all of the pending_stack_adjust
2813 to get this space. */
2815 = (combine_pending_stack_adjustment_and_call
2816 (unadjusted_args_size,
2817 &adjusted_args_size,
2818 preferred_unit_stack_boundary));
2820 /* combine_pending_stack_adjustment_and_call computes
2821 an adjustment before the arguments are allocated.
2822 Account for them and see whether or not the stack
2823 needs to go up or down. */
2824 needed = unadjusted_args_size - needed;
2828 /* We're releasing stack space. */
2829 /* ??? We can avoid any adjustment at all if we're
2830 already aligned. FIXME. */
2831 pending_stack_adjust = -needed;
2832 do_pending_stack_adjust ();
2836 /* We need to allocate space. We'll do that in
2837 push_block below. */
2838 pending_stack_adjust = 0;
2841 /* Special case this because overhead of `push_block' in
2842 this case is non-trivial. */
2844 argblock = virtual_outgoing_args_rtx;
2847 argblock = push_block (GEN_INT (needed), 0, 0);
2848 #ifdef ARGS_GROW_DOWNWARD
2849 argblock = plus_constant (argblock, needed);
2853 /* We only really need to call `copy_to_reg' in the case
2854 where push insns are going to be used to pass ARGBLOCK
2855 to a function call in ARGS. In that case, the stack
2856 pointer changes value from the allocation point to the
2857 call point, and hence the value of
2858 VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
2859 as well always do it. */
2860 argblock = copy_to_reg (argblock);
2865 if (ACCUMULATE_OUTGOING_ARGS)
2867 /* The save/restore code in store_one_arg handles all
2868 cases except one: a constructor call (including a C
2869 function returning a BLKmode struct) to initialize
2871 if (stack_arg_under_construction)
2874 = GEN_INT (adjusted_args_size.constant
2875 + (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype
2876 : TREE_TYPE (fndecl))) ? 0
2877 : reg_parm_stack_space));
2878 if (old_stack_level == 0)
2880 emit_stack_save (SAVE_BLOCK, &old_stack_level);
2881 old_stack_pointer_delta = stack_pointer_delta;
2882 old_pending_adj = pending_stack_adjust;
2883 pending_stack_adjust = 0;
2884 /* stack_arg_under_construction says whether a stack
2885 arg is being constructed at the old stack level.
2886 Pushing the stack gets a clean outgoing argument
2888 old_stack_arg_under_construction
2889 = stack_arg_under_construction;
2890 stack_arg_under_construction = 0;
2891 /* Make a new map for the new argument list. */
2892 free (stack_usage_map_buf);
2893 stack_usage_map_buf = XCNEWVEC (char, highest_outgoing_arg_in_use);
2894 stack_usage_map = stack_usage_map_buf;
2895 highest_outgoing_arg_in_use = 0;
2897 /* We can pass TRUE as the 4th argument because we just
2898 saved the stack pointer and will restore it right after
2900 allocate_dynamic_stack_space (push_size, 0,
2901 BIGGEST_ALIGNMENT, true);
2904 /* If argument evaluation might modify the stack pointer,
2905 copy the address of the argument list to a register. */
2906 for (i = 0; i < num_actuals; i++)
2907 if (args[i].pass_on_stack)
2909 argblock = copy_addr_to_reg (argblock);
2914 compute_argument_addresses (args, argblock, num_actuals);
2916 /* If we push args individually in reverse order, perform stack alignment
2917 before the first push (the last arg). */
2918 if (PUSH_ARGS_REVERSED && argblock == 0
2919 && adjusted_args_size.constant != unadjusted_args_size)
2921 /* When the stack adjustment is pending, we get better code
2922 by combining the adjustments. */
2923 if (pending_stack_adjust
2924 && ! inhibit_defer_pop)
2926 pending_stack_adjust
2927 = (combine_pending_stack_adjustment_and_call
2928 (unadjusted_args_size,
2929 &adjusted_args_size,
2930 preferred_unit_stack_boundary));
2931 do_pending_stack_adjust ();
2933 else if (argblock == 0)
2934 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
2935 - unadjusted_args_size));
2937 /* Now that the stack is properly aligned, pops can't safely
2938 be deferred during the evaluation of the arguments. */
2941 /* Record the maximum pushed stack space size. We need to delay
2942 doing it this far to take into account the optimization done
2943 by combine_pending_stack_adjustment_and_call. */
2944 if (flag_stack_usage_info
2945 && !ACCUMULATE_OUTGOING_ARGS
2947 && adjusted_args_size.var == 0)
2949 int pushed = adjusted_args_size.constant + pending_stack_adjust;
2950 if (pushed > current_function_pushed_stack_size)
2951 current_function_pushed_stack_size = pushed;
2954 funexp = rtx_for_function_call (fndecl, addr);
2956 /* Figure out the register where the value, if any, will come back. */
2958 if (TYPE_MODE (rettype) != VOIDmode
2959 && ! structure_value_addr)
2961 if (pcc_struct_value)
2962 valreg = hard_function_value (build_pointer_type (rettype),
2963 fndecl, NULL, (pass == 0));
2965 valreg = hard_function_value (rettype, fndecl, fntype,
2968 /* If VALREG is a PARALLEL whose first member has a zero
2969 offset, use that. This is for targets such as m68k that
2970 return the same value in multiple places. */
2971 if (GET_CODE (valreg) == PARALLEL)
2973 rtx elem = XVECEXP (valreg, 0, 0);
2974 rtx where = XEXP (elem, 0);
2975 rtx offset = XEXP (elem, 1);
2976 if (offset == const0_rtx
2977 && GET_MODE (where) == GET_MODE (valreg))
2982 /* Precompute all register parameters. It isn't safe to compute anything
2983 once we have started filling any specific hard regs. */
2984 precompute_register_parameters (num_actuals, args, ®_parm_seen);
2986 if (CALL_EXPR_STATIC_CHAIN (exp))
2987 static_chain_value = expand_normal (CALL_EXPR_STATIC_CHAIN (exp));
2989 static_chain_value = 0;
2991 #ifdef REG_PARM_STACK_SPACE
2992 /* Save the fixed argument area if it's part of the caller's frame and
2993 is clobbered by argument setup for this call. */
2994 if (ACCUMULATE_OUTGOING_ARGS && pass)
2995 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
2996 &low_to_save, &high_to_save);
2999 /* Now store (and compute if necessary) all non-register parms.
3000 These come before register parms, since they can require block-moves,
3001 which could clobber the registers used for register parms.
3002 Parms which have partial registers are not stored here,
3003 but we do preallocate space here if they want that. */
3005 for (i = 0; i < num_actuals; i++)
3007 if (args[i].reg == 0 || args[i].pass_on_stack)
3009 rtx before_arg = get_last_insn ();
3011 if (store_one_arg (&args[i], argblock, flags,
3012 adjusted_args_size.var != 0,
3013 reg_parm_stack_space)
3015 && check_sibcall_argument_overlap (before_arg,
3017 sibcall_failure = 1;
3022 = gen_rtx_EXPR_LIST (TYPE_MODE (TREE_TYPE (args[i].tree_value)),
3023 gen_rtx_USE (VOIDmode, args[i].stack),
3027 /* If we have a parm that is passed in registers but not in memory
3028 and whose alignment does not permit a direct copy into registers,
3029 make a group of pseudos that correspond to each register that we
3031 if (STRICT_ALIGNMENT)
3032 store_unaligned_arguments_into_pseudos (args, num_actuals);
3034 /* Now store any partially-in-registers parm.
3035 This is the last place a block-move can happen. */
3037 for (i = 0; i < num_actuals; i++)
3038 if (args[i].partial != 0 && ! args[i].pass_on_stack)
3040 rtx before_arg = get_last_insn ();
3042 if (store_one_arg (&args[i], argblock, flags,
3043 adjusted_args_size.var != 0,
3044 reg_parm_stack_space)
3046 && check_sibcall_argument_overlap (before_arg,
3048 sibcall_failure = 1;
3051 /* If we pushed args in forward order, perform stack alignment
3052 after pushing the last arg. */
3053 if (!PUSH_ARGS_REVERSED && argblock == 0)
3054 anti_adjust_stack (GEN_INT (adjusted_args_size.constant
3055 - unadjusted_args_size));
3057 /* If register arguments require space on the stack and stack space
3058 was not preallocated, allocate stack space here for arguments
3059 passed in registers. */
3060 if (OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl)))
3061 && !ACCUMULATE_OUTGOING_ARGS
3062 && must_preallocate == 0 && reg_parm_stack_space > 0)
3063 anti_adjust_stack (GEN_INT (reg_parm_stack_space));
3065 /* Pass the function the address in which to return a
3067 if (pass != 0 && structure_value_addr && ! structure_value_addr_parm)
3069 structure_value_addr
3070 = convert_memory_address (Pmode, structure_value_addr);
3071 emit_move_insn (struct_value,
3073 force_operand (structure_value_addr,
3076 if (REG_P (struct_value))
3077 use_reg (&call_fusage, struct_value);
3080 after_args = get_last_insn ();
3081 funexp = prepare_call_address (fndecl, funexp, static_chain_value,
3082 &call_fusage, reg_parm_seen, pass == 0);
3084 load_register_parameters (args, num_actuals, &call_fusage, flags,
3085 pass == 0, &sibcall_failure);
3087 /* Save a pointer to the last insn before the call, so that we can
3088 later safely search backwards to find the CALL_INSN. */
3089 before_call = get_last_insn ();
3091 /* Set up next argument register. For sibling calls on machines
3092 with register windows this should be the incoming register. */
3094 next_arg_reg = targetm.calls.function_incoming_arg (args_so_far,
3099 next_arg_reg = targetm.calls.function_arg (args_so_far,
3100 VOIDmode, void_type_node,
3103 /* All arguments and registers used for the call must be set up by
3106 /* Stack must be properly aligned now. */
3108 || !(stack_pointer_delta % preferred_unit_stack_boundary));
3110 /* Generate the actual call instruction. */
3111 emit_call_1 (funexp, exp, fndecl, funtype, unadjusted_args_size,
3112 adjusted_args_size.constant, struct_value_size,
3113 next_arg_reg, valreg, old_inhibit_defer_pop, call_fusage,
3114 flags, args_so_far);
3116 /* If the call setup or the call itself overlaps with anything
3117 of the argument setup we probably clobbered our call address.
3118 In that case we can't do sibcalls. */
3120 && check_sibcall_argument_overlap (after_args, 0, 0))
3121 sibcall_failure = 1;
3123 /* If a non-BLKmode value is returned at the most significant end
3124 of a register, shift the register right by the appropriate amount
3125 and update VALREG accordingly. BLKmode values are handled by the
3126 group load/store machinery below. */
3127 if (!structure_value_addr
3128 && !pcc_struct_value
3129 && TYPE_MODE (rettype) != BLKmode
3130 && targetm.calls.return_in_msb (rettype))
3132 if (shift_return_value (TYPE_MODE (rettype), false, valreg))
3133 sibcall_failure = 1;
3134 valreg = gen_rtx_REG (TYPE_MODE (rettype), REGNO (valreg));
3137 if (pass && (flags & ECF_MALLOC))
3139 rtx temp = gen_reg_rtx (GET_MODE (valreg));
3142 /* The return value from a malloc-like function is a pointer. */
3143 if (TREE_CODE (rettype) == POINTER_TYPE)
3144 mark_reg_pointer (temp, BIGGEST_ALIGNMENT);
3146 emit_move_insn (temp, valreg);
3148 /* The return value from a malloc-like function can not alias
3150 last = get_last_insn ();
3151 add_reg_note (last, REG_NOALIAS, temp);
3153 /* Write out the sequence. */
3154 insns = get_insns ();
3160 /* For calls to `setjmp', etc., inform
3161 function.c:setjmp_warnings that it should complain if
3162 nonvolatile values are live. For functions that cannot
3163 return, inform flow that control does not fall through. */
3165 if ((flags & ECF_NORETURN) || pass == 0)
3167 /* The barrier must be emitted
3168 immediately after the CALL_INSN. Some ports emit more
3169 than just a CALL_INSN above, so we must search for it here. */
3171 rtx last = get_last_insn ();
3172 while (!CALL_P (last))
3174 last = PREV_INSN (last);
3175 /* There was no CALL_INSN? */
3176 gcc_assert (last != before_call);
3179 emit_barrier_after (last);
3181 /* Stack adjustments after a noreturn call are dead code.
3182 However when NO_DEFER_POP is in effect, we must preserve
3183 stack_pointer_delta. */
3184 if (inhibit_defer_pop == 0)
3186 stack_pointer_delta = old_stack_allocated;
3187 pending_stack_adjust = 0;
3191 /* If value type not void, return an rtx for the value. */
3193 if (TYPE_MODE (rettype) == VOIDmode
3195 target = const0_rtx;
3196 else if (structure_value_addr)
3198 if (target == 0 || !MEM_P (target))
3201 = gen_rtx_MEM (TYPE_MODE (rettype),
3202 memory_address (TYPE_MODE (rettype),
3203 structure_value_addr));
3204 set_mem_attributes (target, rettype, 1);
3207 else if (pcc_struct_value)
3209 /* This is the special C++ case where we need to
3210 know what the true target was. We take care to
3211 never use this value more than once in one expression. */
3212 target = gen_rtx_MEM (TYPE_MODE (rettype),
3213 copy_to_reg (valreg));
3214 set_mem_attributes (target, rettype, 1);
3216 /* Handle calls that return values in multiple non-contiguous locations.
3217 The Irix 6 ABI has examples of this. */
3218 else if (GET_CODE (valreg) == PARALLEL)
3222 /* This will only be assigned once, so it can be readonly. */
3223 tree nt = build_qualified_type (rettype,
3224 (TYPE_QUALS (rettype)
3225 | TYPE_QUAL_CONST));
3227 target = assign_temp (nt, 0, 1, 1);
3230 if (! rtx_equal_p (target, valreg))
3231 emit_group_store (target, valreg, rettype,
3232 int_size_in_bytes (rettype));
3234 /* We can not support sibling calls for this case. */
3235 sibcall_failure = 1;
3238 && GET_MODE (target) == TYPE_MODE (rettype)
3239 && GET_MODE (target) == GET_MODE (valreg))
3241 bool may_overlap = false;
3243 /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
3244 reg to a plain register. */
3245 if (!REG_P (target) || HARD_REGISTER_P (target))
3246 valreg = avoid_likely_spilled_reg (valreg);
3248 /* If TARGET is a MEM in the argument area, and we have
3249 saved part of the argument area, then we can't store
3250 directly into TARGET as it may get overwritten when we
3251 restore the argument save area below. Don't work too
3252 hard though and simply force TARGET to a register if it
3253 is a MEM; the optimizer is quite likely to sort it out. */
3254 if (ACCUMULATE_OUTGOING_ARGS && pass && MEM_P (target))
3255 for (i = 0; i < num_actuals; i++)
3256 if (args[i].save_area)
3263 target = copy_to_reg (valreg);
3266 /* TARGET and VALREG cannot be equal at this point
3267 because the latter would not have
3268 REG_FUNCTION_VALUE_P true, while the former would if
3269 it were referring to the same register.
3271 If they refer to the same register, this move will be
3272 a no-op, except when function inlining is being
3274 emit_move_insn (target, valreg);
3276 /* If we are setting a MEM, this code must be executed.
3277 Since it is emitted after the call insn, sibcall
3278 optimization cannot be performed in that case. */
3280 sibcall_failure = 1;
3283 else if (TYPE_MODE (rettype) == BLKmode)
3286 if (GET_MODE (val) != BLKmode)
3287 val = avoid_likely_spilled_reg (val);
3288 target = copy_blkmode_from_reg (target, val, rettype);
3290 /* We can not support sibling calls for this case. */
3291 sibcall_failure = 1;
3294 target = copy_to_reg (avoid_likely_spilled_reg (valreg));
3296 /* If we promoted this return value, make the proper SUBREG.
3297 TARGET might be const0_rtx here, so be careful. */
3299 && TYPE_MODE (rettype) != BLKmode
3300 && GET_MODE (target) != TYPE_MODE (rettype))
3302 tree type = rettype;
3303 int unsignedp = TYPE_UNSIGNED (type);
3305 enum machine_mode pmode;
3307 /* Ensure we promote as expected, and get the new unsignedness. */
3308 pmode = promote_function_mode (type, TYPE_MODE (type), &unsignedp,
3310 gcc_assert (GET_MODE (target) == pmode);
3312 if ((WORDS_BIG_ENDIAN || BYTES_BIG_ENDIAN)
3313 && (GET_MODE_SIZE (GET_MODE (target))
3314 > GET_MODE_SIZE (TYPE_MODE (type))))
3316 offset = GET_MODE_SIZE (GET_MODE (target))
3317 - GET_MODE_SIZE (TYPE_MODE (type));
3318 if (! BYTES_BIG_ENDIAN)
3319 offset = (offset / UNITS_PER_WORD) * UNITS_PER_WORD;
3320 else if (! WORDS_BIG_ENDIAN)
3321 offset %= UNITS_PER_WORD;
3324 target = gen_rtx_SUBREG (TYPE_MODE (type), target, offset);
3325 SUBREG_PROMOTED_VAR_P (target) = 1;
3326 SUBREG_PROMOTED_UNSIGNED_SET (target, unsignedp);
3329 /* If size of args is variable or this was a constructor call for a stack
3330 argument, restore saved stack-pointer value. */
3332 if (old_stack_level)
3334 rtx prev = get_last_insn ();
3336 emit_stack_restore (SAVE_BLOCK, old_stack_level);
3337 stack_pointer_delta = old_stack_pointer_delta;
3339 fixup_args_size_notes (prev, get_last_insn (), stack_pointer_delta);
3341 pending_stack_adjust = old_pending_adj;
3342 old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
3343 stack_arg_under_construction = old_stack_arg_under_construction;
3344 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3345 stack_usage_map = initial_stack_usage_map;
3346 sibcall_failure = 1;
3348 else if (ACCUMULATE_OUTGOING_ARGS && pass)
3350 #ifdef REG_PARM_STACK_SPACE
3352 restore_fixed_argument_area (save_area, argblock,
3353 high_to_save, low_to_save);
3356 /* If we saved any argument areas, restore them. */
3357 for (i = 0; i < num_actuals; i++)
3358 if (args[i].save_area)
3360 enum machine_mode save_mode = GET_MODE (args[i].save_area);
3362 = gen_rtx_MEM (save_mode,
3363 memory_address (save_mode,
3364 XEXP (args[i].stack_slot, 0)));
3366 if (save_mode != BLKmode)
3367 emit_move_insn (stack_area, args[i].save_area);
3369 emit_block_move (stack_area, args[i].save_area,
3370 GEN_INT (args[i].locate.size.constant),
3371 BLOCK_OP_CALL_PARM);
3374 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
3375 stack_usage_map = initial_stack_usage_map;
3378 /* If this was alloca, record the new stack level for nonlocal gotos.
3379 Check for the handler slots since we might not have a save area
3380 for non-local gotos. */
3382 if ((flags & ECF_MAY_BE_ALLOCA) && cfun->nonlocal_goto_save_area != 0)
3383 update_nonlocal_goto_save_area ();
3385 /* Free up storage we no longer need. */
3386 for (i = 0; i < num_actuals; ++i)
3387 free (args[i].aligned_regs);
3389 insns = get_insns ();
3394 tail_call_insns = insns;
3396 /* Restore the pending stack adjustment now that we have
3397 finished generating the sibling call sequence. */
3399 pending_stack_adjust = save_pending_stack_adjust;
3400 stack_pointer_delta = save_stack_pointer_delta;
3402 /* Prepare arg structure for next iteration. */
3403 for (i = 0; i < num_actuals; i++)
3406 args[i].aligned_regs = 0;
3410 sbitmap_free (stored_args_map);
3411 internal_arg_pointer_exp_state.scan_start = NULL_RTX;
3412 VEC_free (rtx, heap, internal_arg_pointer_exp_state.cache);
3416 normal_call_insns = insns;
3418 /* Verify that we've deallocated all the stack we used. */
3419 gcc_assert ((flags & ECF_NORETURN)
3420 || (old_stack_allocated
3421 == stack_pointer_delta - pending_stack_adjust));
3424 /* If something prevents making this a sibling call,
3425 zero out the sequence. */
3426 if (sibcall_failure)
3427 tail_call_insns = NULL_RTX;
3432 /* If tail call production succeeded, we need to remove REG_EQUIV notes on
3433 arguments too, as argument area is now clobbered by the call. */
3434 if (tail_call_insns)
3436 emit_insn (tail_call_insns);
3437 crtl->tail_call_emit = true;
3440 emit_insn (normal_call_insns);
3442 currently_expanding_call--;
3444 free (stack_usage_map_buf);
3449 /* A sibling call sequence invalidates any REG_EQUIV notes made for
3450 this function's incoming arguments.
3452 At the start of RTL generation we know the only REG_EQUIV notes
3453 in the rtl chain are those for incoming arguments, so we can look
3454 for REG_EQUIV notes between the start of the function and the
3455 NOTE_INSN_FUNCTION_BEG.
3457 This is (slight) overkill. We could keep track of the highest
3458 argument we clobber and be more selective in removing notes, but it
3459 does not seem to be worth the effort. */
3462 fixup_tail_calls (void)
3466 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3470 /* There are never REG_EQUIV notes for the incoming arguments
3471 after the NOTE_INSN_FUNCTION_BEG note, so stop if we see it. */
3473 && NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)
3476 note = find_reg_note (insn, REG_EQUIV, 0);
3478 remove_note (insn, note);
3479 note = find_reg_note (insn, REG_EQUIV, 0);
3484 /* Traverse a list of TYPES and expand all complex types into their
3487 split_complex_types (tree types)
3491 /* Before allocating memory, check for the common case of no complex. */
3492 for (p = types; p; p = TREE_CHAIN (p))
3494 tree type = TREE_VALUE (p);
3495 if (TREE_CODE (type) == COMPLEX_TYPE
3496 && targetm.calls.split_complex_arg (type))
3502 types = copy_list (types);
3504 for (p = types; p; p = TREE_CHAIN (p))
3506 tree complex_type = TREE_VALUE (p);
3508 if (TREE_CODE (complex_type) == COMPLEX_TYPE
3509 && targetm.calls.split_complex_arg (complex_type))
3513 /* Rewrite complex type with component type. */
3514 TREE_VALUE (p) = TREE_TYPE (complex_type);
3515 next = TREE_CHAIN (p);
3517 /* Add another component type for the imaginary part. */
3518 imag = build_tree_list (NULL_TREE, TREE_VALUE (p));
3519 TREE_CHAIN (p) = imag;
3520 TREE_CHAIN (imag) = next;
3522 /* Skip the newly created node. */
3530 /* Output a library call to function FUN (a SYMBOL_REF rtx).
3531 The RETVAL parameter specifies whether return value needs to be saved, other
3532 parameters are documented in the emit_library_call function below. */
3535 emit_library_call_value_1 (int retval, rtx orgfun, rtx value,
3536 enum libcall_type fn_type,
3537 enum machine_mode outmode, int nargs, va_list p)
3539 /* Total size in bytes of all the stack-parms scanned so far. */
3540 struct args_size args_size;
3541 /* Size of arguments before any adjustments (such as rounding). */
3542 struct args_size original_args_size;
3545 /* Todo, choose the correct decl type of orgfun. Sadly this information
3546 isn't present here, so we default to native calling abi here. */
3547 tree fndecl ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3548 tree fntype ATTRIBUTE_UNUSED = NULL_TREE; /* library calls default to host calling abi ? */
3552 CUMULATIVE_ARGS args_so_far_v;
3553 cumulative_args_t args_so_far;
3557 enum machine_mode mode;
3560 struct locate_and_pad_arg_data locate;
3564 int old_inhibit_defer_pop = inhibit_defer_pop;
3565 rtx call_fusage = 0;
3568 int pcc_struct_value = 0;
3569 int struct_value_size = 0;
3571 int reg_parm_stack_space = 0;
3574 tree tfom; /* type_for_mode (outmode, 0) */
3576 #ifdef REG_PARM_STACK_SPACE
3577 /* Define the boundary of the register parm stack space that needs to be
3579 int low_to_save = 0, high_to_save = 0;
3580 rtx save_area = 0; /* Place that it is saved. */
3583 /* Size of the stack reserved for parameter registers. */
3584 int initial_highest_arg_in_use = highest_outgoing_arg_in_use;
3585 char *initial_stack_usage_map = stack_usage_map;
3586 char *stack_usage_map_buf = NULL;
3588 rtx struct_value = targetm.calls.struct_value_rtx (0, 0);
3590 #ifdef REG_PARM_STACK_SPACE
3591 reg_parm_stack_space = REG_PARM_STACK_SPACE ((tree) 0);
3594 /* By default, library functions can not throw. */
3595 flags = ECF_NOTHROW;
3608 flags |= ECF_NORETURN;
3611 flags = ECF_NORETURN;
3613 case LCT_RETURNS_TWICE:
3614 flags = ECF_RETURNS_TWICE;
3619 /* Ensure current function's preferred stack boundary is at least
3621 if (crtl->preferred_stack_boundary < PREFERRED_STACK_BOUNDARY)
3622 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
3624 /* If this kind of value comes back in memory,
3625 decide where in memory it should come back. */
3626 if (outmode != VOIDmode)
3628 tfom = lang_hooks.types.type_for_mode (outmode, 0);
3629 if (aggregate_value_p (tfom, 0))
3631 #ifdef PCC_STATIC_STRUCT_RETURN
3633 = hard_function_value (build_pointer_type (tfom), 0, 0, 0);
3634 mem_value = gen_rtx_MEM (outmode, pointer_reg);
3635 pcc_struct_value = 1;
3637 value = gen_reg_rtx (outmode);
3638 #else /* not PCC_STATIC_STRUCT_RETURN */
3639 struct_value_size = GET_MODE_SIZE (outmode);
3640 if (value != 0 && MEM_P (value))
3643 mem_value = assign_temp (tfom, 0, 1, 1);
3645 /* This call returns a big structure. */
3646 flags &= ~(ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE);
3650 tfom = void_type_node;
3652 /* ??? Unfinished: must pass the memory address as an argument. */
3654 /* Copy all the libcall-arguments out of the varargs data
3655 and into a vector ARGVEC.
3657 Compute how to pass each argument. We only support a very small subset
3658 of the full argument passing conventions to limit complexity here since
3659 library functions shouldn't have many args. */
3661 argvec = XALLOCAVEC (struct arg, nargs + 1);
3662 memset (argvec, 0, (nargs + 1) * sizeof (struct arg));
3664 #ifdef INIT_CUMULATIVE_LIBCALL_ARGS
3665 INIT_CUMULATIVE_LIBCALL_ARGS (args_so_far_v, outmode, fun);
3667 INIT_CUMULATIVE_ARGS (args_so_far_v, NULL_TREE, fun, 0, nargs);
3669 args_so_far = pack_cumulative_args (&args_so_far_v);
3671 args_size.constant = 0;
3678 /* If there's a structure value address to be passed,
3679 either pass it in the special place, or pass it as an extra argument. */
3680 if (mem_value && struct_value == 0 && ! pcc_struct_value)
3682 rtx addr = XEXP (mem_value, 0);
3686 /* Make sure it is a reasonable operand for a move or push insn. */
3687 if (!REG_P (addr) && !MEM_P (addr)
3688 && !(CONSTANT_P (addr)
3689 && targetm.legitimate_constant_p (Pmode, addr)))
3690 addr = force_operand (addr, NULL_RTX);
3692 argvec[count].value = addr;
3693 argvec[count].mode = Pmode;
3694 argvec[count].partial = 0;
3696 argvec[count].reg = targetm.calls.function_arg (args_so_far,
3697 Pmode, NULL_TREE, true);
3698 gcc_assert (targetm.calls.arg_partial_bytes (args_so_far, Pmode,
3699 NULL_TREE, 1) == 0);
3701 locate_and_pad_parm (Pmode, NULL_TREE,
3702 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3705 argvec[count].reg != 0,
3707 0, NULL_TREE, &args_size, &argvec[count].locate);
3709 if (argvec[count].reg == 0 || argvec[count].partial != 0
3710 || reg_parm_stack_space > 0)
3711 args_size.constant += argvec[count].locate.size.constant;
3713 targetm.calls.function_arg_advance (args_so_far, Pmode, (tree) 0, true);
3718 for (; count < nargs; count++)
3720 rtx val = va_arg (p, rtx);
3721 enum machine_mode mode = (enum machine_mode) va_arg (p, int);
3724 /* We cannot convert the arg value to the mode the library wants here;
3725 must do it earlier where we know the signedness of the arg. */
3726 gcc_assert (mode != BLKmode
3727 && (GET_MODE (val) == mode || GET_MODE (val) == VOIDmode));
3729 /* Make sure it is a reasonable operand for a move or push insn. */
3730 if (!REG_P (val) && !MEM_P (val)
3731 && !(CONSTANT_P (val) && targetm.legitimate_constant_p (mode, val)))
3732 val = force_operand (val, NULL_RTX);
3734 if (pass_by_reference (&args_so_far_v, mode, NULL_TREE, 1))
3738 = !reference_callee_copied (&args_so_far_v, mode, NULL_TREE, 1);
3740 /* If this was a CONST function, it is now PURE since it now
3742 if (flags & ECF_CONST)
3744 flags &= ~ECF_CONST;
3748 if (MEM_P (val) && !must_copy)
3750 tree val_expr = MEM_EXPR (val);
3752 mark_addressable (val_expr);
3757 slot = assign_temp (lang_hooks.types.type_for_mode (mode, 0),
3759 emit_move_insn (slot, val);
3762 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3763 gen_rtx_USE (VOIDmode, slot),
3766 call_fusage = gen_rtx_EXPR_LIST (VOIDmode,
3767 gen_rtx_CLOBBER (VOIDmode,
3772 val = force_operand (XEXP (slot, 0), NULL_RTX);
3775 mode = promote_function_mode (NULL_TREE, mode, &unsigned_p, NULL_TREE, 0);
3776 argvec[count].mode = mode;
3777 argvec[count].value = convert_modes (mode, GET_MODE (val), val, unsigned_p);
3778 argvec[count].reg = targetm.calls.function_arg (args_so_far, mode,
3781 argvec[count].partial
3782 = targetm.calls.arg_partial_bytes (args_so_far, mode, NULL_TREE, 1);
3784 if (argvec[count].reg == 0
3785 || argvec[count].partial != 0
3786 || reg_parm_stack_space > 0)
3788 locate_and_pad_parm (mode, NULL_TREE,
3789 #ifdef STACK_PARMS_IN_REG_PARM_AREA
3792 argvec[count].reg != 0,
3794 argvec[count].partial,
3795 NULL_TREE, &args_size, &argvec[count].locate);
3796 args_size.constant += argvec[count].locate.size.constant;
3797 gcc_assert (!argvec[count].locate.size.var);
3799 #ifdef BLOCK_REG_PADDING
3801 /* The argument is passed entirely in registers. See at which
3802 end it should be padded. */
3803 argvec[count].locate.where_pad =
3804 BLOCK_REG_PADDING (mode, NULL_TREE,
3805 GET_MODE_SIZE (mode) <= UNITS_PER_WORD);
3808 targetm.calls.function_arg_advance (args_so_far, mode, (tree) 0, true);
3811 /* If this machine requires an external definition for library
3812 functions, write one out. */
3813 assemble_external_libcall (fun);
3815 original_args_size = args_size;
3816 args_size.constant = (((args_size.constant
3817 + stack_pointer_delta
3821 - stack_pointer_delta);
3823 args_size.constant = MAX (args_size.constant,
3824 reg_parm_stack_space);
3826 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3827 args_size.constant -= reg_parm_stack_space;
3829 if (args_size.constant > crtl->outgoing_args_size)
3830 crtl->outgoing_args_size = args_size.constant;
3832 if (flag_stack_usage_info && !ACCUMULATE_OUTGOING_ARGS)
3834 int pushed = args_size.constant + pending_stack_adjust;
3835 if (pushed > current_function_pushed_stack_size)
3836 current_function_pushed_stack_size = pushed;
3839 if (ACCUMULATE_OUTGOING_ARGS)
3841 /* Since the stack pointer will never be pushed, it is possible for
3842 the evaluation of a parm to clobber something we have already
3843 written to the stack. Since most function calls on RISC machines
3844 do not use the stack, this is uncommon, but must work correctly.
3846 Therefore, we save any area of the stack that was already written
3847 and that we are using. Here we set up to do this by making a new
3848 stack usage map from the old one.
3850 Another approach might be to try to reorder the argument
3851 evaluations to avoid this conflicting stack usage. */
3853 needed = args_size.constant;
3855 /* Since we will be writing into the entire argument area, the
3856 map must be allocated for its entire size, not just the part that
3857 is the responsibility of the caller. */
3858 if (! OUTGOING_REG_PARM_STACK_SPACE ((!fndecl ? fntype : TREE_TYPE (fndecl))))
3859 needed += reg_parm_stack_space;
3861 #ifdef ARGS_GROW_DOWNWARD
3862 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3865 highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
3868 stack_usage_map_buf = XNEWVEC (char, highest_outgoing_arg_in_use);
3869 stack_usage_map = stack_usage_map_buf;
3871 if (initial_highest_arg_in_use)
3872 memcpy (stack_usage_map, initial_stack_usage_map,
3873 initial_highest_arg_in_use);
3875 if (initial_highest_arg_in_use != highest_outgoing_arg_in_use)
3876 memset (&stack_usage_map[initial_highest_arg_in_use], 0,
3877 highest_outgoing_arg_in_use - initial_highest_arg_in_use);
3880 /* We must be careful to use virtual regs before they're instantiated,
3881 and real regs afterwards. Loop optimization, for example, can create
3882 new libcalls after we've instantiated the virtual regs, and if we
3883 use virtuals anyway, they won't match the rtl patterns. */
3885 if (virtuals_instantiated)
3886 argblock = plus_constant (stack_pointer_rtx, STACK_POINTER_OFFSET);
3888 argblock = virtual_outgoing_args_rtx;
3893 argblock = push_block (GEN_INT (args_size.constant), 0, 0);
3896 /* If we push args individually in reverse order, perform stack alignment
3897 before the first push (the last arg). */
3898 if (argblock == 0 && PUSH_ARGS_REVERSED)
3899 anti_adjust_stack (GEN_INT (args_size.constant
3900 - original_args_size.constant));
3902 if (PUSH_ARGS_REVERSED)
3913 #ifdef REG_PARM_STACK_SPACE
3914 if (ACCUMULATE_OUTGOING_ARGS)
3916 /* The argument list is the property of the called routine and it
3917 may clobber it. If the fixed area has been used for previous
3918 parameters, we must save and restore it. */
3919 save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
3920 &low_to_save, &high_to_save);
3924 /* Push the args that need to be pushed. */
3926 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
3927 are to be pushed. */
3928 for (count = 0; count < nargs; count++, argnum += inc)
3930 enum machine_mode mode = argvec[argnum].mode;
3931 rtx val = argvec[argnum].value;
3932 rtx reg = argvec[argnum].reg;
3933 int partial = argvec[argnum].partial;
3934 unsigned int parm_align = argvec[argnum].locate.boundary;
3935 int lower_bound = 0, upper_bound = 0, i;
3937 if (! (reg != 0 && partial == 0))
3941 if (ACCUMULATE_OUTGOING_ARGS)
3943 /* If this is being stored into a pre-allocated, fixed-size,
3944 stack area, save any previous data at that location. */
3946 #ifdef ARGS_GROW_DOWNWARD
3947 /* stack_slot is negative, but we want to index stack_usage_map
3948 with positive values. */
3949 upper_bound = -argvec[argnum].locate.slot_offset.constant + 1;
3950 lower_bound = upper_bound - argvec[argnum].locate.size.constant;
3952 lower_bound = argvec[argnum].locate.slot_offset.constant;
3953 upper_bound = lower_bound + argvec[argnum].locate.size.constant;
3957 /* Don't worry about things in the fixed argument area;
3958 it has already been saved. */
3959 if (i < reg_parm_stack_space)
3960 i = reg_parm_stack_space;
3961 while (i < upper_bound && stack_usage_map[i] == 0)
3964 if (i < upper_bound)
3966 /* We need to make a save area. */
3968 = argvec[argnum].locate.size.constant * BITS_PER_UNIT;
3969 enum machine_mode save_mode
3970 = mode_for_size (size, MODE_INT, 1);
3972 = plus_constant (argblock,
3973 argvec[argnum].locate.offset.constant);
3975 = gen_rtx_MEM (save_mode, memory_address (save_mode, adr));
3977 if (save_mode == BLKmode)
3979 argvec[argnum].save_area
3980 = assign_stack_temp (BLKmode,
3981 argvec[argnum].locate.size.constant,
3984 emit_block_move (validize_mem (argvec[argnum].save_area),
3986 GEN_INT (argvec[argnum].locate.size.constant),
3987 BLOCK_OP_CALL_PARM);
3991 argvec[argnum].save_area = gen_reg_rtx (save_mode);
3993 emit_move_insn (argvec[argnum].save_area, stack_area);
3998 emit_push_insn (val, mode, NULL_TREE, NULL_RTX, parm_align,
3999 partial, reg, 0, argblock,
4000 GEN_INT (argvec[argnum].locate.offset.constant),
4001 reg_parm_stack_space,
4002 ARGS_SIZE_RTX (argvec[argnum].locate.alignment_pad));
4004 /* Now mark the segment we just used. */
4005 if (ACCUMULATE_OUTGOING_ARGS)
4006 for (i = lower_bound; i < upper_bound; i++)
4007 stack_usage_map[i] = 1;
4011 /* Indicate argument access so that alias.c knows that these
4014 use = plus_constant (argblock,
4015 argvec[argnum].locate.offset.constant);
4017 /* When arguments are pushed, trying to tell alias.c where
4018 exactly this argument is won't work, because the
4019 auto-increment causes confusion. So we merely indicate
4020 that we access something with a known mode somewhere on
4022 use = gen_rtx_PLUS (Pmode, virtual_outgoing_args_rtx,
4023 gen_rtx_SCRATCH (Pmode));
4024 use = gen_rtx_MEM (argvec[argnum].mode, use);
4025 use = gen_rtx_USE (VOIDmode, use);
4026 call_fusage = gen_rtx_EXPR_LIST (VOIDmode, use, call_fusage);
4030 /* If we pushed args in forward order, perform stack alignment
4031 after pushing the last arg. */
4032 if (argblock == 0 && !PUSH_ARGS_REVERSED)
4033 anti_adjust_stack (GEN_INT (args_size.constant
4034 - original_args_size.constant));
4036 if (PUSH_ARGS_REVERSED)
4041 fun = prepare_call_address (NULL, fun, NULL, &call_fusage, 0, 0);
4043 /* Now load any reg parms into their regs. */
4045 /* ARGNUM indexes the ARGVEC array in the order in which the arguments
4046 are to be pushed. */
4047 for (count = 0; count < nargs; count++, argnum += inc)
4049 enum machine_mode mode = argvec[argnum].mode;
4050 rtx val = argvec[argnum].value;
4051 rtx reg = argvec[argnum].reg;
4052 int partial = argvec[argnum].partial;
4053 #ifdef BLOCK_REG_PADDING
4057 /* Handle calls that pass values in multiple non-contiguous
4058 locations. The PA64 has examples of this for library calls. */
4059 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4060 emit_group_load (reg, val, NULL_TREE, GET_MODE_SIZE (mode));
4061 else if (reg != 0 && partial == 0)
4063 emit_move_insn (reg, val);
4064 #ifdef BLOCK_REG_PADDING
4065 size = GET_MODE_SIZE (argvec[argnum].mode);
4067 /* Copied from load_register_parameters. */
4069 /* Handle case where we have a value that needs shifting
4070 up to the msb. eg. a QImode value and we're padding
4071 upward on a BYTES_BIG_ENDIAN machine. */
4072 if (size < UNITS_PER_WORD
4073 && (argvec[argnum].locate.where_pad
4074 == (BYTES_BIG_ENDIAN ? upward : downward)))
4077 int shift = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4079 /* Assigning REG here rather than a temp makes CALL_FUSAGE
4080 report the whole reg as used. Strictly speaking, the
4081 call only uses SIZE bytes at the msb end, but it doesn't
4082 seem worth generating rtl to say that. */
4083 reg = gen_rtx_REG (word_mode, REGNO (reg));
4084 x = expand_shift (LSHIFT_EXPR, word_mode, reg, shift, reg, 1);
4086 emit_move_insn (reg, x);
4094 /* Any regs containing parms remain in use through the call. */
4095 for (count = 0; count < nargs; count++)
4097 rtx reg = argvec[count].reg;
4098 if (reg != 0 && GET_CODE (reg) == PARALLEL)
4099 use_group_regs (&call_fusage, reg);
4102 int partial = argvec[count].partial;
4106 gcc_assert (partial % UNITS_PER_WORD == 0);
4107 nregs = partial / UNITS_PER_WORD;
4108 use_regs (&call_fusage, REGNO (reg), nregs);
4111 use_reg (&call_fusage, reg);
4115 /* Pass the function the address in which to return a structure value. */
4116 if (mem_value != 0 && struct_value != 0 && ! pcc_struct_value)
4118 emit_move_insn (struct_value,
4120 force_operand (XEXP (mem_value, 0),
4122 if (REG_P (struct_value))
4123 use_reg (&call_fusage, struct_value);
4126 /* Don't allow popping to be deferred, since then
4127 cse'ing of library calls could delete a call and leave the pop. */
4129 valreg = (mem_value == 0 && outmode != VOIDmode
4130 ? hard_libcall_value (outmode, orgfun) : NULL_RTX);
4132 /* Stack must be properly aligned now. */
4133 gcc_assert (!(stack_pointer_delta
4134 & (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT - 1)));
4136 before_call = get_last_insn ();
4138 /* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
4139 will set inhibit_defer_pop to that value. */
4140 /* The return type is needed to decide how many bytes the function pops.
4141 Signedness plays no role in that, so for simplicity, we pretend it's
4142 always signed. We also assume that the list of arguments passed has
4143 no impact, so we pretend it is unknown. */
4145 emit_call_1 (fun, NULL,
4146 get_identifier (XSTR (orgfun, 0)),
4147 build_function_type (tfom, NULL_TREE),
4148 original_args_size.constant, args_size.constant,
4150 targetm.calls.function_arg (args_so_far,
4151 VOIDmode, void_type_node, true),
4153 old_inhibit_defer_pop + 1, call_fusage, flags, args_so_far);
4155 /* Right-shift returned value if necessary. */
4156 if (!pcc_struct_value
4157 && TYPE_MODE (tfom) != BLKmode
4158 && targetm.calls.return_in_msb (tfom))
4160 shift_return_value (TYPE_MODE (tfom), false, valreg);
4161 valreg = gen_rtx_REG (TYPE_MODE (tfom), REGNO (valreg));
4164 /* For calls to `setjmp', etc., inform function.c:setjmp_warnings
4165 that it should complain if nonvolatile values are live. For
4166 functions that cannot return, inform flow that control does not
4169 if (flags & ECF_NORETURN)
4171 /* The barrier note must be emitted
4172 immediately after the CALL_INSN. Some ports emit more than
4173 just a CALL_INSN above, so we must search for it here. */
4175 rtx last = get_last_insn ();
4176 while (!CALL_P (last))
4178 last = PREV_INSN (last);
4179 /* There was no CALL_INSN? */
4180 gcc_assert (last != before_call);
4183 emit_barrier_after (last);
4186 /* Now restore inhibit_defer_pop to its actual original value. */
4191 /* Copy the value to the right place. */
4192 if (outmode != VOIDmode && retval)
4198 if (value != mem_value)
4199 emit_move_insn (value, mem_value);
4201 else if (GET_CODE (valreg) == PARALLEL)
4204 value = gen_reg_rtx (outmode);
4205 emit_group_store (value, valreg, NULL_TREE, GET_MODE_SIZE (outmode));
4209 /* Convert to the proper mode if a promotion has been active. */
4210 if (GET_MODE (valreg) != outmode)
4212 int unsignedp = TYPE_UNSIGNED (tfom);
4214 gcc_assert (promote_function_mode (tfom, outmode, &unsignedp,
4215 fndecl ? TREE_TYPE (fndecl) : fntype, 1)
4216 == GET_MODE (valreg));
4217 valreg = convert_modes (outmode, GET_MODE (valreg), valreg, 0);
4221 emit_move_insn (value, valreg);
4227 if (ACCUMULATE_OUTGOING_ARGS)
4229 #ifdef REG_PARM_STACK_SPACE
4231 restore_fixed_argument_area (save_area, argblock,
4232 high_to_save, low_to_save);
4235 /* If we saved any argument areas, restore them. */
4236 for (count = 0; count < nargs; count++)
4237 if (argvec[count].save_area)
4239 enum machine_mode save_mode = GET_MODE (argvec[count].save_area);
4240 rtx adr = plus_constant (argblock,
4241 argvec[count].locate.offset.constant);
4242 rtx stack_area = gen_rtx_MEM (save_mode,
4243 memory_address (save_mode, adr));
4245 if (save_mode == BLKmode)
4246 emit_block_move (stack_area,
4247 validize_mem (argvec[count].save_area),
4248 GEN_INT (argvec[count].locate.size.constant),
4249 BLOCK_OP_CALL_PARM);
4251 emit_move_insn (stack_area, argvec[count].save_area);
4254 highest_outgoing_arg_in_use = initial_highest_arg_in_use;
4255 stack_usage_map = initial_stack_usage_map;
4258 free (stack_usage_map_buf);
4264 /* Output a library call to function FUN (a SYMBOL_REF rtx)
4265 (emitting the queue unless NO_QUEUE is nonzero),
4266 for a value of mode OUTMODE,
4267 with NARGS different arguments, passed as alternating rtx values
4268 and machine_modes to convert them to.
4270 FN_TYPE should be LCT_NORMAL for `normal' calls, LCT_CONST for
4271 `const' calls, LCT_PURE for `pure' calls, or other LCT_ value for
4272 other types of library calls. */
4275 emit_library_call (rtx orgfun, enum libcall_type fn_type,
4276 enum machine_mode outmode, int nargs, ...)
4280 va_start (p, nargs);
4281 emit_library_call_value_1 (0, orgfun, NULL_RTX, fn_type, outmode, nargs, p);
4285 /* Like emit_library_call except that an extra argument, VALUE,
4286 comes second and says where to store the result.
4287 (If VALUE is zero, this function chooses a convenient way
4288 to return the value.
4290 This function returns an rtx for where the value is to be found.
4291 If VALUE is nonzero, VALUE is returned. */
4294 emit_library_call_value (rtx orgfun, rtx value,
4295 enum libcall_type fn_type,
4296 enum machine_mode outmode, int nargs, ...)
4301 va_start (p, nargs);
4302 result = emit_library_call_value_1 (1, orgfun, value, fn_type, outmode,
4309 /* Store a single argument for a function call
4310 into the register or memory area where it must be passed.
4311 *ARG describes the argument value and where to pass it.
4313 ARGBLOCK is the address of the stack-block for all the arguments,
4314 or 0 on a machine where arguments are pushed individually.
4316 MAY_BE_ALLOCA nonzero says this could be a call to `alloca'
4317 so must be careful about how the stack is used.
4319 VARIABLE_SIZE nonzero says that this was a variable-sized outgoing
4320 argument stack. This is used if ACCUMULATE_OUTGOING_ARGS to indicate
4321 that we need not worry about saving and restoring the stack.
4323 FNDECL is the declaration of the function we are calling.
4325 Return nonzero if this arg should cause sibcall failure,
4329 store_one_arg (struct arg_data *arg, rtx argblock, int flags,
4330 int variable_size ATTRIBUTE_UNUSED, int reg_parm_stack_space)
4332 tree pval = arg->tree_value;
4336 int i, lower_bound = 0, upper_bound = 0;
4337 int sibcall_failure = 0;
4339 if (TREE_CODE (pval) == ERROR_MARK)
4342 /* Push a new temporary level for any temporaries we make for
4346 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
4348 /* If this is being stored into a pre-allocated, fixed-size, stack area,
4349 save any previous data at that location. */
4350 if (argblock && ! variable_size && arg->stack)
4352 #ifdef ARGS_GROW_DOWNWARD
4353 /* stack_slot is negative, but we want to index stack_usage_map
4354 with positive values. */
4355 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4356 upper_bound = -INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1)) + 1;
4360 lower_bound = upper_bound - arg->locate.size.constant;
4362 if (GET_CODE (XEXP (arg->stack_slot, 0)) == PLUS)
4363 lower_bound = INTVAL (XEXP (XEXP (arg->stack_slot, 0), 1));
4367 upper_bound = lower_bound + arg->locate.size.constant;
4371 /* Don't worry about things in the fixed argument area;
4372 it has already been saved. */
4373 if (i < reg_parm_stack_space)
4374 i = reg_parm_stack_space;
4375 while (i < upper_bound && stack_usage_map[i] == 0)
4378 if (i < upper_bound)
4380 /* We need to make a save area. */
4381 unsigned int size = arg->locate.size.constant * BITS_PER_UNIT;
4382 enum machine_mode save_mode = mode_for_size (size, MODE_INT, 1);
4383 rtx adr = memory_address (save_mode, XEXP (arg->stack_slot, 0));
4384 rtx stack_area = gen_rtx_MEM (save_mode, adr);
4386 if (save_mode == BLKmode)
4388 tree ot = TREE_TYPE (arg->tree_value);
4389 tree nt = build_qualified_type (ot, (TYPE_QUALS (ot)
4390 | TYPE_QUAL_CONST));
4392 arg->save_area = assign_temp (nt, 0, 1, 1);
4393 preserve_temp_slots (arg->save_area);
4394 emit_block_move (validize_mem (arg->save_area), stack_area,
4395 GEN_INT (arg->locate.size.constant),
4396 BLOCK_OP_CALL_PARM);
4400 arg->save_area = gen_reg_rtx (save_mode);
4401 emit_move_insn (arg->save_area, stack_area);
4407 /* If this isn't going to be placed on both the stack and in registers,
4408 set up the register and number of words. */
4409 if (! arg->pass_on_stack)
4411 if (flags & ECF_SIBCALL)
4412 reg = arg->tail_call_reg;
4415 partial = arg->partial;
4418 /* Being passed entirely in a register. We shouldn't be called in
4420 gcc_assert (reg == 0 || partial != 0);
4422 /* If this arg needs special alignment, don't load the registers
4424 if (arg->n_aligned_regs != 0)
4427 /* If this is being passed partially in a register, we can't evaluate
4428 it directly into its stack slot. Otherwise, we can. */
4429 if (arg->value == 0)
4431 /* stack_arg_under_construction is nonzero if a function argument is
4432 being evaluated directly into the outgoing argument list and
4433 expand_call must take special action to preserve the argument list
4434 if it is called recursively.
4436 For scalar function arguments stack_usage_map is sufficient to
4437 determine which stack slots must be saved and restored. Scalar
4438 arguments in general have pass_on_stack == 0.
4440 If this argument is initialized by a function which takes the
4441 address of the argument (a C++ constructor or a C function
4442 returning a BLKmode structure), then stack_usage_map is
4443 insufficient and expand_call must push the stack around the
4444 function call. Such arguments have pass_on_stack == 1.
4446 Note that it is always safe to set stack_arg_under_construction,
4447 but this generates suboptimal code if set when not needed. */
4449 if (arg->pass_on_stack)
4450 stack_arg_under_construction++;
4452 arg->value = expand_expr (pval,
4454 || TYPE_MODE (TREE_TYPE (pval)) != arg->mode)
4455 ? NULL_RTX : arg->stack,
4456 VOIDmode, EXPAND_STACK_PARM);
4458 /* If we are promoting object (or for any other reason) the mode
4459 doesn't agree, convert the mode. */
4461 if (arg->mode != TYPE_MODE (TREE_TYPE (pval)))
4462 arg->value = convert_modes (arg->mode, TYPE_MODE (TREE_TYPE (pval)),
4463 arg->value, arg->unsignedp);
4465 if (arg->pass_on_stack)
4466 stack_arg_under_construction--;
4469 /* Check for overlap with already clobbered argument area. */
4470 if ((flags & ECF_SIBCALL)
4471 && MEM_P (arg->value)
4472 && mem_overlaps_already_clobbered_arg_p (XEXP (arg->value, 0),
4473 arg->locate.size.constant))
4474 sibcall_failure = 1;
4476 /* Don't allow anything left on stack from computation
4477 of argument to alloca. */
4478 if (flags & ECF_MAY_BE_ALLOCA)
4479 do_pending_stack_adjust ();
4481 if (arg->value == arg->stack)
4482 /* If the value is already in the stack slot, we are done. */
4484 else if (arg->mode != BLKmode)
4487 unsigned int parm_align;
4489 /* Argument is a scalar, not entirely passed in registers.
4490 (If part is passed in registers, arg->partial says how much
4491 and emit_push_insn will take care of putting it there.)
4493 Push it, and if its size is less than the
4494 amount of space allocated to it,
4495 also bump stack pointer by the additional space.
4496 Note that in C the default argument promotions
4497 will prevent such mismatches. */
4499 size = GET_MODE_SIZE (arg->mode);
4500 /* Compute how much space the push instruction will push.
4501 On many machines, pushing a byte will advance the stack
4502 pointer by a halfword. */
4503 #ifdef PUSH_ROUNDING
4504 size = PUSH_ROUNDING (size);
4508 /* Compute how much space the argument should get:
4509 round up to a multiple of the alignment for arguments. */
4510 if (none != FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)))
4511 used = (((size + PARM_BOUNDARY / BITS_PER_UNIT - 1)
4512 / (PARM_BOUNDARY / BITS_PER_UNIT))
4513 * (PARM_BOUNDARY / BITS_PER_UNIT));
4515 /* Compute the alignment of the pushed argument. */
4516 parm_align = arg->locate.boundary;
4517 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4519 int pad = used - size;
4522 unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
4523 parm_align = MIN (parm_align, pad_align);
4527 /* This isn't already where we want it on the stack, so put it there.
4528 This can either be done with push or copy insns. */
4529 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
4530 parm_align, partial, reg, used - size, argblock,
4531 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4532 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4534 /* Unless this is a partially-in-register argument, the argument is now
4537 arg->value = arg->stack;
4541 /* BLKmode, at least partly to be pushed. */
4543 unsigned int parm_align;
4547 /* Pushing a nonscalar.
4548 If part is passed in registers, PARTIAL says how much
4549 and emit_push_insn will take care of putting it there. */
4551 /* Round its size up to a multiple
4552 of the allocation unit for arguments. */
4554 if (arg->locate.size.var != 0)
4557 size_rtx = ARGS_SIZE_RTX (arg->locate.size);
4561 /* PUSH_ROUNDING has no effect on us, because emit_push_insn
4562 for BLKmode is careful to avoid it. */
4563 excess = (arg->locate.size.constant
4564 - int_size_in_bytes (TREE_TYPE (pval))
4566 size_rtx = expand_expr (size_in_bytes (TREE_TYPE (pval)),
4567 NULL_RTX, TYPE_MODE (sizetype),
4571 parm_align = arg->locate.boundary;
4573 /* When an argument is padded down, the block is aligned to
4574 PARM_BOUNDARY, but the actual argument isn't. */
4575 if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
4577 if (arg->locate.size.var)
4578 parm_align = BITS_PER_UNIT;
4581 unsigned int excess_align = (excess & -excess) * BITS_PER_UNIT;
4582 parm_align = MIN (parm_align, excess_align);
4586 if ((flags & ECF_SIBCALL) && MEM_P (arg->value))
4588 /* emit_push_insn might not work properly if arg->value and
4589 argblock + arg->locate.offset areas overlap. */
4593 if (XEXP (x, 0) == crtl->args.internal_arg_pointer
4594 || (GET_CODE (XEXP (x, 0)) == PLUS
4595 && XEXP (XEXP (x, 0), 0) ==
4596 crtl->args.internal_arg_pointer
4597 && CONST_INT_P (XEXP (XEXP (x, 0), 1))))
4599 if (XEXP (x, 0) != crtl->args.internal_arg_pointer)
4600 i = INTVAL (XEXP (XEXP (x, 0), 1));
4602 /* expand_call should ensure this. */
4603 gcc_assert (!arg->locate.offset.var
4604 && arg->locate.size.var == 0
4605 && CONST_INT_P (size_rtx));
4607 if (arg->locate.offset.constant > i)
4609 if (arg->locate.offset.constant < i + INTVAL (size_rtx))
4610 sibcall_failure = 1;
4612 else if (arg->locate.offset.constant < i)
4614 /* Use arg->locate.size.constant instead of size_rtx
4615 because we only care about the part of the argument
4617 if (i < (arg->locate.offset.constant
4618 + arg->locate.size.constant))
4619 sibcall_failure = 1;
4623 /* Even though they appear to be at the same location,
4624 if part of the outgoing argument is in registers,
4625 they aren't really at the same location. Check for
4626 this by making sure that the incoming size is the
4627 same as the outgoing size. */
4628 if (arg->locate.size.constant != INTVAL (size_rtx))
4629 sibcall_failure = 1;
4634 emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
4635 parm_align, partial, reg, excess, argblock,
4636 ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
4637 ARGS_SIZE_RTX (arg->locate.alignment_pad));
4639 /* Unless this is a partially-in-register argument, the argument is now
4642 ??? Unlike the case above, in which we want the actual
4643 address of the data, so that we can load it directly into a
4644 register, here we want the address of the stack slot, so that
4645 it's properly aligned for word-by-word copying or something
4646 like that. It's not clear that this is always correct. */
4648 arg->value = arg->stack_slot;
4651 if (arg->reg && GET_CODE (arg->reg) == PARALLEL)
4653 tree type = TREE_TYPE (arg->tree_value);
4655 = emit_group_load_into_temps (arg->reg, arg->value, type,
4656 int_size_in_bytes (type));
4659 /* Mark all slots this store used. */
4660 if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL)
4661 && argblock && ! variable_size && arg->stack)
4662 for (i = lower_bound; i < upper_bound; i++)
4663 stack_usage_map[i] = 1;
4665 /* Once we have pushed something, pops can't safely
4666 be deferred during the rest of the arguments. */
4669 /* Free any temporary slots made in processing this argument. Show
4670 that we might have taken the address of something and pushed that
4672 preserve_temp_slots (NULL_RTX);
4676 return sibcall_failure;
4679 /* Nonzero if we do not know how to pass TYPE solely in registers. */
4682 must_pass_in_stack_var_size (enum machine_mode mode ATTRIBUTE_UNUSED,
4688 /* If the type has variable size... */
4689 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4692 /* If the type is marked as addressable (it is required
4693 to be constructed into the stack)... */
4694 if (TREE_ADDRESSABLE (type))
4700 /* Another version of the TARGET_MUST_PASS_IN_STACK hook. This one
4701 takes trailing padding of a structure into account. */
4702 /* ??? Should be able to merge these two by examining BLOCK_REG_PADDING. */
4705 must_pass_in_stack_var_size_or_pad (enum machine_mode mode, const_tree type)
4710 /* If the type has variable size... */
4711 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4714 /* If the type is marked as addressable (it is required
4715 to be constructed into the stack)... */
4716 if (TREE_ADDRESSABLE (type))
4719 /* If the padding and mode of the type is such that a copy into
4720 a register would put it into the wrong part of the register. */
4722 && int_size_in_bytes (type) % (PARM_BOUNDARY / BITS_PER_UNIT)
4723 && (FUNCTION_ARG_PADDING (mode, type)
4724 == (BYTES_BIG_ENDIAN ? upward : downward)))