| blob | e4a8694054e2bbd98c0d8361689c17e607a28364 |
1 /* Expand builtin functions.
2 Copyright (C) 1988-2020 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* Legacy warning! Please add no further builtin simplifications here
21 (apart from pure constant folding) - builtin simplifications should go
22 to match.pd or gimple-fold.c instead. */
78 #if SWITCHABLE_TARGET
80 #endif
82 /* Define the names of the builtin function types and codes. */
86 #define DEF_BUILTIN(X, N, C, T, LT, B, F, NA, AT, IM, COND) #X,
88 {
90 };
92 /* Setup an array of builtin_info_type, make sure each element decl is
93 initialized to NULL_TREE. */
96 /* Non-zero if __builtin_constant_p should be folded right away. */
130 memop_ret retmode,
195 /* Return true if NAME starts with __builtin_ or __sync_. */
197 static bool
199 {
207 }
209 /* Return true if NODE should be considered for inline expansion regardless
210 of the optimization level. This means whenever a function is invoked with
211 its "internal" name, which normally contains the prefix "__builtin". */
213 bool
215 {
216 /* Note that we must use DECL_NAME, not DECL_ASSEMBLER_NAME_SET_P since
217 we want the name used to call the function, not the name it
218 will have. */
221 }
223 /* Compute values M and N such that M divides (address of EXP - N) and such
224 that N < M. If these numbers can be determined, store M in alignp and N in
225 *BITPOSP and return true. Otherwise return false and store BITS_PER_UNIT to
226 *alignp and any bit-offset to *bitposp.
228 Note that the address (and thus the alignment) computed here is based
229 on the address to which a symbol resolves, whereas DECL_ALIGN is based
230 on the address at which an object is actually located. These two
231 addresses are not always the same. For example, on ARM targets,
232 the address &foo of a Thumb function foo() has the lowest bit set,
233 whereas foo() itself starts on an even address.
235 If ADDR_P is true we are taking the address of the memory reference EXP
236 and thus cannot rely on the access taking place. */
238 static bool
241 {
243 tree offset;
244 machine_mode mode;
249 /* Get the innermost object and the constant (bitpos) and possibly
250 variable (offset) offset of the access. */
254 /* Extract alignment information from the innermost object and
255 possibly adjust bitpos and offset. */
257 {
258 /* Function addresses can encode extra information besides their
259 alignment. However, if TARGET_PTRMEMFUNC_VBIT_LOCATION
260 allows the low bit to be used as a virtual bit, we know
261 that the address itself must be at least 2-byte aligned. */
264 }
266 ;
268 {
269 /* The alignment of a CONST_DECL is determined by its initializer. */
276 }
278 {
281 }
285 {
291 /* If the address is explicitely aligned, handle that. */
294 {
299 }
301 known_alignment
305 /* Re-apply explicit alignment to the bitpos. */
308 /* The alignment of the pointer operand in a TARGET_MEM_REF
309 has to take the variable offset parts into account. */
311 {
313 {
318 }
322 }
324 /* When EXP is an actual memory reference then we can use
325 TYPE_ALIGN of a pointer indirection to derive alignment.
326 Do so only if get_pointer_alignment_1 did not reveal absolute
327 alignment knowledge and if using that alignment would
328 improve the situation. */
334 else
335 {
336 /* Else adjust bitpos accordingly. */
341 }
342 }
344 {
345 /* STRING_CST are the only constant objects we allow to be not
346 wrapped inside a CONST_DECL. */
352 }
354 /* If there is a non-constant offset part extract the maximum
355 alignment that can prevail. */
357 {
360 {
364 }
365 }
367 /* Account for the alignment of runtime coefficients, so that the constant
368 bitpos is guaranteed to be accurate. */
371 {
374 }
379 }
381 /* For a memory reference expression EXP compute values M and N such that M
382 divides (&EXP - N) and such that N < M. If these numbers can be determined,
383 store M in alignp and N in *BITPOSP and return true. Otherwise return false
384 and store BITS_PER_UNIT to *alignp and any bit-offset to *bitposp. */
386 bool
389 {
391 }
393 /* Return the alignment in bits of EXP, an object. */
395 unsigned int
397 {
403 /* align and bitpos now specify known low bits of the pointer.
404 ptr & (align - 1) == bitpos. */
409 }
411 /* For a pointer valued expression EXP compute values M and N such that M
412 divides (EXP - N) and such that N < M. If these numbers can be determined,
413 store M in alignp and N in *BITPOSP and return true. Return false if
414 the results are just a conservative approximation.
416 If EXP is not a pointer, false is returned too. */
418 bool
421 {
428 {
435 else
436 {
439 {
443 }
444 }
448 }
451 {
456 {
459 /* Make sure to return a sensible alignment when the multiplication
460 by BITS_PER_UNIT overflowed. */
463 /* We cannot really tell whether this result is an approximation. */
465 }
466 else
467 {
471 }
472 }
474 {
479 }
484 }
486 /* Return the alignment in bits of EXP, a pointer valued expression.
487 The alignment returned is, by default, the alignment of the thing that
488 EXP points to. If it is not a POINTER_TYPE, 0 is returned.
490 Otherwise, look at the expression to see if we can do better, i.e., if the
491 expression is actually pointing at an object whose alignment is tighter. */
493 unsigned int
495 {
501 /* align and bitpos now specify known low bits of the pointer.
502 ptr & (align - 1) == bitpos. */
508 }
510 /* Return the number of leading non-zero elements in the sequence
511 [ PTR, PTR + MAXELTS ) where each element's size is ELTSIZE bytes.
512 ELTSIZE must be a power of 2 less than 8. Used by c_strlen. */
514 unsigned
516 {
522 {
523 /* Optimize the common case of plain char. */
525 {
529 }
530 }
531 else
532 {
534 {
538 }
539 }
541 }
543 /* For a call at LOC to a function FN that expects a string in the argument
544 ARG, issue a diagnostic due to it being a called with an argument
545 declared at NONSTR that is a character array with no terminating NUL. */
547 void
549 {
557 {
561 }
562 }
564 /* For a call EXPR (which may be null) that expects a string argument
565 and SRC as the argument, returns false if SRC is a character array
566 with no terminating NUL. When nonnull, BOUND is the number of
567 characters in which to expect the terminating NUL.
568 When EXPR is nonnull also issues a warning. */
570 bool
572 {
573 tree size;
579 /* NONSTR refers to the non-nul terminated constant array and SIZE
580 is the constant size of the array in bytes. EXACT is true when
581 SIZE is exact. */
584 {
588 else
589 {
593 }
597 }
600 {
604 }
607 }
609 /* If EXP refers to an unterminated constant character array return
610 the declaration of the object of which the array is a member or
611 element and if SIZE is not null, set *SIZE to the size of
612 the unterminated array and set *EXACT if the size is exact or
613 clear it otherwise. Otherwise return null. */
615 tree
617 {
618 /* C_STRLEN will return NULL and set DECL in the info
619 structure if EXP references a unterminated array. */
620 c_strlen_data lendata = { };
623 {
625 {
628 {
629 /* Constant offsets are already accounted for in LENDATA.MINLEN,
630 but not in a SSA_NAME + CST expression. */
635 {
636 /* Subtract the offset from the size of the array. */
641 }
642 else
644 }
645 else
649 }
651 }
654 }
656 /* Compute the length of a null-terminated character string or wide
657 character string handling character sizes of 1, 2, and 4 bytes.
658 TREE_STRING_LENGTH is not the right way because it evaluates to
659 the size of the character array in bytes (as opposed to characters)
660 and because it can contain a zero byte in the middle.
662 ONLY_VALUE should be nonzero if the result is not going to be emitted
663 into the instruction stream and zero if it is going to be expanded.
664 E.g. with i++ ? "foo" : "bar", if ONLY_VALUE is nonzero, constant 3
665 is returned, otherwise NULL, since
666 len = c_strlen (ARG, 1); if (len) expand_expr (len, ...); would not
667 evaluate the side-effects.
669 If ONLY_VALUE is two then we do not emit warnings about out-of-bound
670 accesses. Note that this implies the result is not going to be emitted
671 into the instruction stream.
673 Additional information about the string accessed may be recorded
674 in DATA. For example, if ARG references an unterminated string,
675 then the declaration will be stored in the DECL field. If the
676 length of the unterminated string can be determined, it'll be
677 stored in the LEN field. Note this length could well be different
678 than what a C strlen call would return.
680 ELTSIZE is 1 for normal single byte character strings, and 2 or
681 4 for wide characer strings. ELTSIZE is by default 1.
683 The value returned is of type `ssizetype'. */
685 tree
687 {
688 /* If we were not passed a DATA pointer, then get one to a local
689 structure. That avoids having to check DATA for NULL before
690 each time we want to use it. */
691 c_strlen_data local_strlen_data = { };
700 {
707 }
715 /* Offset from the beginning of the string in bytes. */
716 tree byteoff;
717 tree memsize;
718 tree decl;
723 /* Determine the size of the string element. */
727 /* Set MAXELTS to sizeof (SRC) / sizeof (*SRC) - 1, the maximum possible
728 length of SRC. Prefer TYPE_SIZE() to TREE_STRING_LENGTH() if possible
729 in case the latter is less than the size of the array, such as when
730 SRC refers to a short string literal used to initialize a large array.
731 In that case, the elements of the array after the terminating NUL are
732 all NUL. */
741 /* PTR can point to the byte representation of any string type, including
742 char* and wchar_t*. */
746 {
747 /* The code below works only for single byte character types. */
751 /* If the string has an internal NUL character followed by any
752 non-NUL characters (e.g., "foo\0bar"), we can't compute
753 the offset to the following NUL if we don't know where to
754 start searching for it. */
757 /* Return when an embedded null character is found or none at all.
758 In the latter case, set the DECL/LEN field in the DATA structure
759 so that callers may examine them. */
763 {
768 }
770 /* For empty strings the result should be zero. */
774 /* We don't know the starting offset, but we do know that the string
775 has no internal zero bytes. If the offset falls within the bounds
776 of the string subtract the offset from the length of the string,
777 and return that. Otherwise the length is zero. Take care to
778 use SAVE_EXPR in case the OFFSET has side-effects. */
785 offsave);
789 }
791 /* Offset from the beginning of the string in elements. */
792 HOST_WIDE_INT eltoff;
794 /* We have a known offset into the string. Start searching there for
795 a null character if we can represent it as a single HOST_WIDE_INT. */
800 else
803 /* If the offset is known to be out of bounds, warn, and call strlen at
804 runtime. */
806 {
807 /* Suppress multiple warnings for propagated constant strings. */
812 eltoff))
813 {
817 }
819 }
821 /* If eltoff is larger than strelts but less than maxelts the
822 string length is zero, since the excess memory will be zero. */
826 /* Use strlen to search for the first zero byte. Since any strings
827 constructed with build_string will have nulls appended, we win even
828 if we get handed something like (char[4])"abcd".
830 Since ELTOFF is our starting index into the string, no further
831 calculation is needed. */
835 /* Don't know what to return if there was no zero termination.
836 Ideally this would turn into a gcc_checking_assert over time.
837 Set DECL/LEN so callers can examine them. */
839 {
844 }
847 }
849 /* Return a constant integer corresponding to target reading
850 GET_MODE_BITSIZE (MODE) bits from string constant STR. If
851 NULL_TERMINATED_P, reading stops after '\0' character, all further ones
852 are assumed to be zero, otherwise it reads as many characters
853 as needed. */
855 rtx
858 {
859 HOST_WIDE_INT ch;
873 {
885 }
889 }
891 /* Cast a target constant CST to target CHAR and if that value fits into
892 host char type, return zero and put that value into variable pointed to by
893 P. */
895 static int
897 {
904 /* Do not care if it fits or not right here. */
919 }
921 /* Similar to save_expr, but assumes that arbitrary code is not executed
922 in between the multiple evaluations. In particular, we assume that a
923 non-addressable local variable will not be modified. */
925 static tree
927 {
935 }
937 /* Given TEM, a pointer to a stack frame, follow the dynamic chain COUNT
938 times to get the address of either a higher stack frame, or a return
939 address located within it (depending on FNDECL_CODE). */
941 static rtx
943 {
947 {
948 /* For a zero count with __builtin_return_address, we don't care what
949 frame address we return, because target-specific definitions will
950 override us. Therefore frame pointer elimination is OK, and using
951 the soft frame pointer is OK.
953 For a nonzero count, or a zero count with __builtin_frame_address,
954 we require a stable offset from the current frame pointer to the
955 previous one, so we must use the hard frame pointer, and
956 we must disable frame pointer elimination. */
959 else
960 {
963 /* Tell reload not to eliminate the frame pointer. */
965 }
966 }
971 /* On the SPARC, the return address is not in the frame, it is in a
972 register. There is no way to access it off of the current frame
973 pointer, but it can be accessed off the previous frame pointer by
974 reading the value from the register window save area. */
976 count--;
978 /* Scan back COUNT frames to the specified frame. */
980 {
981 /* Assume the dynamic chain pointer is in the word that the
982 frame address points to, unless otherwise specified. */
987 }
989 /* For __builtin_frame_address, return what we've got. But, on
990 the SPARC for example, we may have to add a bias. */
994 /* For __builtin_return_address, get the return address from that frame. */
995 #ifdef RETURN_ADDR_RTX
997 #else
1001 #endif
1003 }
1005 /* Alias set used for setjmp buffer. */
1008 /* Construct the leading half of a __builtin_setjmp call. Control will
1009 return to RECEIVER_LABEL. This is also called directly by the SJLJ
1010 exception handling code. */
1012 void
1014 {
1016 rtx stack_save;
1017 rtx mem;
1026 /* We store the frame pointer and the address of receiver_label in
1027 the buffer and use the rest of it for the stack save area, which
1028 is machine-dependent. */
1047 /* If there is further processing to do, do it. */
1051 /* We have a nonlocal label. */
1053 }
1055 /* Construct the trailing part of a __builtin_setjmp call. This is
1056 also called directly by the SJLJ exception handling code.
1057 If RECEIVER_LABEL is NULL, instead contruct a nonlocal goto handler. */
1059 void
1061 {
1062 rtx chain;
1064 /* Mark the FP as used when we get here, so we have to make sure it's
1065 marked as used by this function. */
1068 /* Mark the static chain as clobbered here so life information
1069 doesn't get messed up for it. */
1075 {
1076 /* If the argument pointer can be eliminated in favor of the
1077 frame pointer, we don't need to restore it. We assume here
1078 that if such an elimination is present, it can always be used.
1079 This is the case on all known machines; if we don't make this
1080 assumption, we do unnecessary saving on many machines. */
1090 {
1091 /* Now restore our arg pointer from the address at which it
1092 was saved in our stack frame. */
1095 }
1096 }
1102 else
1105 /* We must not allow the code we just generated to be reordered by
1106 scheduling. Specifically, the update of the frame pointer must
1107 happen immediately, not later. */
1109 }
1111 /* __builtin_longjmp is passed a pointer to an array of five words (not
1112 all will be used on all machines). It operates similarly to the C
1113 library function of the same name, but is more efficient. Much of
1114 the code below is copied from the handling of non-local gotos. */
1116 static void
1118 {
1123 /* DRAP is needed for stack realign if longjmp is expanded to current
1124 function */
1135 /* We require that the user must pass a second argument of 1, because
1136 that is what builtin_setjmp will return. */
1142 else
1143 {
1154 /* Pick up FP, label, and SP from the block and jump. This code is
1155 from expand_goto in stmt.c; see there for detailed comments. */
1157 /* We have to pass a value to the nonlocal_goto pattern that will
1158 get copied into the static_chain pointer, but it does not matter
1159 what that value is, because builtin_setjmp does not use it. */
1161 else
1162 {
1168 /* Restore the frame pointer and stack pointer. We must use a
1169 temporary since the setjmp buffer may be a local. */
1173 /* Ensure the frame pointer move is not optimized. */
1182 }
1183 }
1185 /* Search backwards and mark the jump insn as a non-local goto.
1186 Note that this precludes the use of __builtin_longjmp to a
1187 __builtin_setjmp target in the same function. However, we've
1188 already cautioned the user that these functions are for
1189 internal exception handling use only. */
1191 {
1195 {
1198 }
1201 }
1202 }
1206 {
1208 }
1210 /* This function validates the types of a function call argument list
1211 against a specified list of tree_codes. If the last specifier is a 0,
1212 that represents an ellipsis, otherwise the last specifier must be a
1213 VOID_TYPE. */
1215 static bool
1217 {
1221 const_call_expr_arg_iterator iter;
1222 const_tree arg;
1227 /* Get a bitmap of pointer argument numbers declared attribute nonnull. */
1232 {
1236 {
1238 /* This signifies an ellipses, any further arguments are all ok. */
1242 /* This signifies an endlink, if no arguments remain, return
1243 true, otherwise return false. */
1247 /* The actual argument must be nonnull when either the whole
1248 called function has been declared nonnull, or when the formal
1249 argument corresponding to the actual argument has been. */
1252 {
1257 }
1258 /* FALLTHRU */
1260 /* If no parameters remain or the parameter's code does not
1261 match the specified code, return false. Otherwise continue
1262 checking any remaining arguments. */
1267 }
1268 }
1270 /* We need gotos here since we can only have one VA_CLOSE in a
1271 function. */
1272 end: ;
1278 }
1280 /* Expand a call to __builtin_nonlocal_goto. We're passed the target label
1281 and the address of the save area. */
1283 static rtx
1285 {
1300 /* Copy the address of the save location to a register just in case it was
1301 based on the frame pointer. */
1310 /* ??? We no longer need to pass the static chain value, afaik. */
1313 else
1314 {
1320 /* Restore the frame pointer and stack pointer. We must use a
1321 temporary since the setjmp buffer may be a local. */
1325 /* Ensure the frame pointer move is not optimized. */
1331 /* USE of hard_frame_pointer_rtx added for consistency;
1332 not clear if really needed. */
1336 /* If the architecture is using a GP register, we must
1337 conservatively assume that the target function makes use of it.
1338 The prologue of functions with nonlocal gotos must therefore
1339 initialize the GP register to the appropriate value, and we
1340 must then make sure that this value is live at the point
1341 of the jump. (Note that this doesn't necessarily apply
1342 to targets with a nonlocal_goto pattern; they are free
1343 to implement it in their own way. Note also that this is
1344 a no-op if the GP register is a global invariant.) */
1350 }
1352 /* Search backwards to the jump insn and mark it as a
1353 non-local goto. */
1355 {
1357 {
1360 }
1363 }
1366 }
1368 /* __builtin_update_setjmp_buf is passed a pointer to an array of five words
1369 (not all will be used on all machines) that was passed to __builtin_setjmp.
1370 It updates the stack pointer in that block to the current value. This is
1371 also called directly by the SJLJ exception handling code. */
1373 void
1375 {
1378 rtx stack_save
1380 memory_address
1386 }
1388 /* Expand a call to __builtin_prefetch. For a target that does not support
1389 data prefetch, evaluate the memory address argument in case it has side
1390 effects. */
1392 static void
1394 {
1404 /* Arguments 1 and 2 are optional; argument 1 (read/write) defaults to
1405 zero (read) and argument 2 (locality) defaults to 3 (high degree of
1406 locality). */
1410 else
1414 else
1417 /* Argument 0 is an address. */
1420 /* Argument 1 (read/write flag) must be a compile-time constant int. */
1422 {
1425 }
1427 /* Argument 1 must be either zero or one. */
1429 {
1433 }
1435 /* Argument 2 (locality) must be a compile-time constant int. */
1437 {
1440 }
1442 /* Argument 2 must be 0, 1, 2, or 3. */
1444 {
1447 }
1450 {
1458 }
1460 /* Don't do anything with direct references to volatile memory, but
1461 generate code to handle other side effects. */
1464 }
1466 /* Get a MEM rtx for expression EXP which is the address of an operand
1467 to be used in a string instruction (cmpstrsi, cpymemsi, ..). LEN is
1468 the maximum length of the block of memory that might be accessed or
1469 NULL if unknown. */
1471 static rtx
1473 {
1477 /* When EXP is not resolved SAVE_EXPR, MEM_ATTRS can be still derived
1478 from its expression, for expr->a.b only <variable>.a.b is recorded. */
1485 /* Get an expression we can use to find the attributes to assign to MEM.
1486 First remove any nops. */
1491 /* Build a MEM_REF representing the whole accessed area as a byte blob,
1492 (as builtin stringops may alias with anything). */
1499 /* If the MEM_REF has no acceptable address, try to get the base object
1500 from the original address we got, and build an all-aliasing
1501 unknown-sized access to that one. */
1507 {
1512 size_zero_node,
1513 NULL)),
1516 }
1519 }
1520 \f
1521 /* Built-in functions to perform an untyped call and return. */
1523 #define apply_args_mode \
1524 (this_target_builtins->x_apply_args_mode)
1525 #define apply_result_mode \
1526 (this_target_builtins->x_apply_result_mode)
1528 /* Return the size required for the block returned by __builtin_apply_args,
1529 and initialize apply_args_mode. */
1531 static int
1533 {
1538 /* The values computed by this function never change. */
1540 {
1541 /* The first value is the incoming arg-pointer. */
1544 /* The second value is the structure value address unless this is
1545 passed as an "invisible" first argument. */
1551 {
1561 }
1562 else
1563 {
1565 }
1566 }
1568 }
1570 /* Return the size required for the block returned by __builtin_apply,
1571 and initialize apply_result_mode. */
1573 static int
1575 {
1579 /* The values computed by this function never change. */
1581 {
1586 {
1596 }
1597 else
1600 /* Allow targets that use untyped_call and untyped_return to override
1601 the size so that machine-specific information can be stored here. */
1602 #ifdef APPLY_RESULT_SIZE
1604 #endif
1605 }
1607 }
1609 /* Create a vector describing the result block RESULT. If SAVEP is true,
1610 the result block is used to save the values; otherwise it is used to
1611 restore the values. */
1613 static rtx
1615 {
1617 fixed_size_mode mode;
1624 {
1634 }
1636 }
1638 /* Save the state required to perform an untyped call with the same
1639 arguments as were passed to the current function. */
1641 static rtx
1643 {
1646 fixed_size_mode mode;
1647 rtx struct_incoming_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 1);
1649 /* Create a block where the arg-pointer, structure value address,
1650 and argument registers can be saved. */
1653 /* Walk past the arg-pointer and structure value address. */
1658 /* Save each register used in calling a function to the block. */
1661 {
1670 }
1672 /* Save the arg pointer to the block. */
1674 /* We need the pointer as the caller actually passed them to us, not
1675 as we might have pretended they were passed. Make sure it's a valid
1676 operand, as emit_move_insn isn't expected to handle a PLUS. */
1678 tem
1681 NULL_RTX);
1686 /* Save the structure value address unless this is passed as an
1687 "invisible" first argument. */
1692 /* Return the address of the block. */
1694 }
1696 /* __builtin_apply_args returns block of memory allocated on
1697 the stack into which is stored the arg pointer, structure
1698 value address, static chain, and all the registers that might
1699 possibly be used in performing a function call. The code is
1700 moved to the start of the function so the incoming values are
1701 saved. */
1703 static rtx
1705 {
1706 /* Don't do __builtin_apply_args more than once in a function.
1707 Save the result of the first call and reuse it. */
1710 {
1711 /* When this function is called, it means that registers must be
1712 saved on entry to this function. So we migrate the
1713 call to the first insn of this function. */
1714 rtx temp;
1723 /* Put the insns after the NOTE that starts the function.
1724 If this is inside a start_sequence, make the outer-level insn
1725 chain current, so the code is placed at the start of the
1726 function. If internal_arg_pointer is a non-virtual pseudo,
1727 it needs to be placed after the function that initializes
1728 that pseudo. */
1733 else
1737 }
1738 }
1740 /* Perform an untyped call and save the state required to perform an
1741 untyped return of whatever value was returned by the given function. */
1743 static rtx
1745 {
1747 fixed_size_mode mode;
1756 /* Create a block where the return registers can be saved. */
1759 /* Fetch the arg pointer from the ARGUMENTS block. */
1766 /* Push a new argument block and copy the arguments. Do not allow
1767 the (potential) memcpy call below to interfere with our stack
1768 manipulations. */
1770 NO_DEFER_POP;
1772 /* Save the stack with nonlocal if available. */
1775 else
1778 /* Allocate a block of memory onto the stack and copy the memory
1779 arguments to the outgoing arguments address. We can pass TRUE
1780 as the 4th argument because we just saved the stack pointer
1781 and will restore it right after the call. */
1784 /* Set DRAP flag to true, even though allocate_dynamic_stack_space
1785 may have already set current_function_calls_alloca to true.
1786 current_function_calls_alloca won't be set if argsize is zero,
1787 so we have to guarantee need_drap is true here. */
1793 {
1796 else
1798 }
1805 /* Refer to the argument block. */
1810 /* Walk past the arg-pointer and structure value address. */
1815 /* Restore each of the registers previously saved. Make USE insns
1816 for each of these registers for use in making the call. */
1819 {
1827 }
1829 /* Restore the structure value address unless this is passed as an
1830 "invisible" first argument. */
1833 {
1839 }
1841 /* All arguments and registers used for the call are set up by now! */
1844 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
1845 and we don't want to load it into a register as an optimization,
1846 because prepare_call_address already did it if it should be done. */
1850 /* Generate the actual call instruction and save the return value. */
1852 {
1856 }
1858 {
1861 /* Locate the unique return register. It is not possible to
1862 express a call that sets more than one return register using
1863 call_value; use untyped_call for that. In fact, untyped_call
1864 only needs to save the return registers in the given block. */
1867 {
1871 }
1878 }
1879 else
1882 /* Find the CALL insn we just emitted, and attach the register usage
1883 information. */
1887 /* Restore the stack. */
1890 else
1894 OK_DEFER_POP;
1896 /* Return the address of the result block. */
1899 }
1901 /* Perform an untyped return. */
1903 static void
1905 {
1907 fixed_size_mode mode;
1908 rtx reg;
1917 {
1922 }
1924 /* Restore the return value and note that each value is used. */
1928 {
1940 }
1942 /* Put the USE insns before the return. */
1945 /* Return whatever values was restored by jumping directly to the end
1946 of the function. */
1948 }
1950 /* Used by expand_builtin_classify_type and fold_builtin_classify_type. */
1952 static enum type_class
1954 {
1956 {
1975 }
1976 }
1978 /* Expand a call EXP to __builtin_classify_type. */
1980 static rtx
1982 {
1986 }
1988 /* This helper macro, meant to be used in mathfn_built_in below, determines
1989 which among a set of builtin math functions is appropriate for a given type
1990 mode. The `F' (float) and `L' (long double) are automatically generated
1991 from the 'double' case. If a function supports the _Float<N> and _Float<N>X
1992 types, there are additional types that are considered with 'F32', 'F64',
1993 'F128', etc. suffixes. */
1994 #define CASE_MATHFN(MATHFN) \
1995 CASE_CFN_##MATHFN: \
1996 fcode = BUILT_IN_##MATHFN; fcodef = BUILT_IN_##MATHFN##F ; \
1997 fcodel = BUILT_IN_##MATHFN##L ; break;
1998 /* Similar to the above, but also add support for the _Float<N> and _Float<N>X
1999 types. */
2000 #define CASE_MATHFN_FLOATN(MATHFN) \
2001 CASE_CFN_##MATHFN: \
2002 fcode = BUILT_IN_##MATHFN; fcodef = BUILT_IN_##MATHFN##F ; \
2003 fcodel = BUILT_IN_##MATHFN##L ; fcodef16 = BUILT_IN_##MATHFN##F16 ; \
2004 fcodef32 = BUILT_IN_##MATHFN##F32; fcodef64 = BUILT_IN_##MATHFN##F64 ; \
2005 fcodef128 = BUILT_IN_##MATHFN##F128 ; fcodef32x = BUILT_IN_##MATHFN##F32X ; \
2006 fcodef64x = BUILT_IN_##MATHFN##F64X ; fcodef128x = BUILT_IN_##MATHFN##F128X ;\
2007 break;
2008 /* Similar to above, but appends _R after any F/L suffix. */
2009 #define CASE_MATHFN_REENT(MATHFN) \
2010 case CFN_BUILT_IN_##MATHFN##_R: \
2011 case CFN_BUILT_IN_##MATHFN##F_R: \
2012 case CFN_BUILT_IN_##MATHFN##L_R: \
2013 fcode = BUILT_IN_##MATHFN##_R; fcodef = BUILT_IN_##MATHFN##F_R ; \
2014 fcodel = BUILT_IN_##MATHFN##L_R ; break;
2016 /* Return a function equivalent to FN but operating on floating-point
2017 values of type TYPE, or END_BUILTINS if no such function exists.
2018 This is purely an operation on function codes; it does not guarantee
2019 that the target actually has an implementation of the function. */
2021 static built_in_function
2023 {
2024 tree mtype;
2035 {
2127 }
2150 else
2152 }
2154 /* Return mathematic function equivalent to FN but operating directly on TYPE,
2155 if available. If IMPLICIT_P is true use the implicit builtin declaration,
2156 otherwise use the explicit declaration. If we can't do the conversion,
2157 return null. */
2159 static tree
2161 {
2170 }
2172 /* Like mathfn_built_in_1, but always use the implicit array. */
2174 tree
2176 {
2178 }
2180 /* Like mathfn_built_in_1, but take a built_in_function and
2181 always use the implicit array. */
2183 tree
2185 {
2187 }
2189 /* If BUILT_IN_NORMAL function FNDECL has an associated internal function,
2190 return its code, otherwise return IFN_LAST. Note that this function
2191 only tests whether the function is defined in internals.def, not whether
2192 it is actually available on the target. */
2194 internal_fn
2196 {
2200 {
2201 #define DEF_INTERNAL_FLT_FN(NAME, FLAGS, OPTAB, TYPE) \
2202 CASE_FLT_FN (BUILT_IN_##NAME): return IFN_##NAME;
2203 #define DEF_INTERNAL_FLT_FLOATN_FN(NAME, FLAGS, OPTAB, TYPE) \
2204 CASE_FLT_FN (BUILT_IN_##NAME): return IFN_##NAME; \
2205 CASE_FLT_FN_FLOATN_NX (BUILT_IN_##NAME): return IFN_##NAME;
2206 #define DEF_INTERNAL_INT_FN(NAME, FLAGS, OPTAB, TYPE) \
2207 CASE_INT_FN (BUILT_IN_##NAME): return IFN_##NAME;
2224 }
2225 }
2227 /* If CALL is a call to a BUILT_IN_NORMAL function that could be replaced
2228 on the current target by a call to an internal function, return the
2229 code of that internal function, otherwise return IFN_LAST. The caller
2230 is responsible for ensuring that any side-effects of the built-in
2231 call are dealt with correctly. E.g. if CALL sets errno, the caller
2232 must decide that the errno result isn't needed or make it available
2233 in some other way. */
2235 internal_fn
2237 {
2239 {
2242 {
2247 }
2248 }
2250 }
2252 /* Expand a call to the builtin trinary math functions (fma).
2253 Return NULL_RTX if a normal call should be emitted rather than expanding the
2254 function in-line. EXP is the expression that is a call to the builtin
2255 function; if convenient, the result should be placed in TARGET.
2256 SUBTARGET may be used as the target for computing one of EXP's
2257 operands. */
2259 static rtx
2261 {
2262 optab builtin_optab;
2267 machine_mode mode;
2277 {
2283 }
2285 /* Make a suitable register to place result in. */
2288 /* Before working hard, check whether the instruction is available. */
2294 /* Always stabilize the argument list. */
2305 /* Compute into RESULT.
2306 Set RESULT to wherever the result comes back. */
2310 /* If we were unable to expand via the builtin, stop the sequence
2311 (without outputting the insns) and call to the library function
2312 with the stabilized argument list. */
2314 {
2317 }
2319 /* Output the entire sequence. */
2325 }
2327 /* Expand a call to the builtin sin and cos math functions.
2328 Return NULL_RTX if a normal call should be emitted rather than expanding the
2329 function in-line. EXP is the expression that is a call to the builtin
2330 function; if convenient, the result should be placed in TARGET.
2331 SUBTARGET may be used as the target for computing one of EXP's
2332 operands. */
2334 static rtx
2336 {
2337 optab builtin_optab;
2338 rtx op0;
2341 machine_mode mode;
2342 tree arg;
2350 {
2356 }
2358 /* Make a suitable register to place result in. */
2361 /* Check if sincos insn is available, otherwise fallback
2362 to sin or cos insn. */
2365 {
2372 }
2374 /* Before working hard, check whether the instruction is available. */
2376 {
2379 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2380 need to expand the argument again. This way, we will not perform
2381 side-effects more the once. */
2388 /* Compute into RESULT.
2389 Set RESULT to wherever the result comes back. */
2391 {
2395 {
2404 }
2406 }
2407 else
2411 {
2412 /* Output the entire sequence. */
2417 }
2419 /* If we were unable to expand via the builtin, stop the sequence
2420 (without outputting the insns) and call to the library function
2421 with the stabilized argument list. */
2423 }
2426 }
2428 /* Given an interclass math builtin decl FNDECL and it's argument ARG
2429 return an RTL instruction code that implements the functionality.
2430 If that isn't possible or available return CODE_FOR_nothing. */
2432 static enum insn_code
2434 {
2437 machine_mode mode;
2440 {
2454 /* These builtins have no optabs (yet). */
2458 }
2460 /* There's no easy way to detect the case we need to set EDOM. */
2464 /* Optab mode depends on the mode of the input argument. */
2470 }
2472 /* Expand a call to one of the builtin math functions that operate on
2473 floating point argument and output an integer result (ilogb, isinf,
2474 isnan, etc).
2475 Return 0 if a normal call should be emitted rather than expanding the
2476 function in-line. EXP is the expression that is a call to the builtin
2477 function; if convenient, the result should be placed in TARGET. */
2479 static rtx
2481 {
2483 rtx op0;
2485 machine_mode mode;
2486 tree arg;
2496 {
2501 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2502 need to expand the argument again. This way, we will not perform
2503 side-effects more the once. */
2518 }
2521 }
2523 /* Expand a call to the builtin sincos math function.
2524 Return NULL_RTX if a normal call should be emitted rather than expanding the
2525 function in-line. EXP is the expression that is a call to the builtin
2526 function. */
2528 static rtx
2530 {
2532 machine_mode mode;
2546 /* Make a suitable register to place result in. */
2549 /* Check if sincos insn is available, otherwise emit the call. */
2564 /* Compute into target1 and target2.
2565 Set TARGET to wherever the result comes back. */
2569 /* Move target1 and target2 to the memory locations indicated
2570 by op1 and op2. */
2575 }
2577 /* Expand a call to the internal cexpi builtin to the sincos math function.
2578 EXP is the expression that is a call to the builtin function; if convenient,
2579 the result should be placed in TARGET. */
2581 static rtx
2583 {
2586 machine_mode mode;
2597 /* Try expanding via a sincos optab, fall back to emitting a libcall
2598 to sincos or cexp. We are sure we have sincos or cexp because cexpi
2599 is only generated from sincos, cexp or if we have either of them. */
2601 {
2607 /* Compute into op1 and op2. */
2609 }
2611 {
2622 else
2632 /* Make sure not to fold the sincos call again. */
2636 }
2637 else
2638 {
2648 else
2651 /* If we don't have a decl for cexp create one. This is the
2652 friendliest fallback if the user calls __builtin_cexpi
2653 without full target C99 function support. */
2655 {
2656 tree fntype;
2668 }
2673 /* Make sure not to fold the cexp call again. */
2677 }
2679 /* Now build the proper return type. */
2684 }
2686 /* Conveniently construct a function call expression. FNDECL names the
2687 function to be called, N is the number of arguments, and the "..."
2688 parameters are the argument expressions. Unlike build_call_exr
2689 this doesn't fold the call, hence it will always return a CALL_EXPR. */
2691 static tree
2693 {
2703 }
2705 /* Expand a call to one of the builtin rounding functions gcc defines
2706 as an extension (lfloor and lceil). As these are gcc extensions we
2707 do not need to worry about setting errno to EDOM.
2708 If expanding via optab fails, lower expression to (int)(floor(x)).
2709 EXP is the expression that is a call to the builtin function;
2710 if convenient, the result should be placed in TARGET. */
2712 static rtx
2714 {
2715 convert_optab builtin_optab;
2720 tree fallback_fndecl;
2721 machine_mode mode;
2722 tree arg;
2730 {
2747 }
2749 /* Make a suitable register to place result in. */
2754 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2755 need to expand the argument again. This way, we will not perform
2756 side-effects more the once. */
2763 /* Compute into TARGET. */
2765 {
2766 /* Output the entire sequence. */
2771 }
2773 /* If we were unable to expand via the builtin, stop the sequence
2774 (without outputting the insns). */
2777 /* Fall back to floating point rounding optab. */
2780 /* For non-C99 targets we may end up without a fallback fndecl here
2781 if the user called __builtin_lfloor directly. In this case emit
2782 a call to the floor/ceil variants nevertheless. This should result
2783 in the best user experience for not full C99 targets. */
2785 {
2786 tree fntype;
2790 {
2823 }
2828 }
2835 /* Truncate the result of floating point optab to integer
2836 via expand_fix (). */
2841 }
2843 /* Expand a call to one of the builtin math functions doing integer
2844 conversion (lrint).
2845 Return 0 if a normal call should be emitted rather than expanding the
2846 function in-line. EXP is the expression that is a call to the builtin
2847 function; if convenient, the result should be placed in TARGET. */
2849 static rtx
2851 {
2852 convert_optab builtin_optab;
2853 rtx op0;
2856 tree arg;
2857 machine_mode mode;
2866 {
2885 }
2887 /* There's no easy way to detect the case we need to set EDOM. */
2891 /* Make a suitable register to place result in. */
2894 /* There's no easy way to detect the case we need to set EDOM. */
2896 {
2899 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2900 need to expand the argument again. This way, we will not perform
2901 side-effects more the once. */
2909 {
2910 /* Output the entire sequence. */
2915 }
2917 /* If we were unable to expand via the builtin, stop the sequence
2918 (without outputting the insns) and call to the library function
2919 with the stabilized argument list. */
2921 }
2924 {
2925 /* Fall back to rounding to long int. Use implicit_p 0 - for non-C99
2926 targets, (int) round (x) should never be transformed into
2927 BUILT_IN_IROUND and if __builtin_iround is called directly, emit
2928 a call to lround in the hope that the target provides at least some
2929 C99 functions. This should result in the best user experience for
2930 not full C99 targets. */
2931 tree fallback_fndecl = mathfn_built_in_1
2940 }
2943 }
2945 /* Expand a call to the powi built-in mathematical function. Return NULL_RTX if
2946 a normal call should be emitted rather than expanding the function
2947 in-line. EXP is the expression that is a call to the builtin
2948 function; if convenient, the result should be placed in TARGET. */
2950 static rtx
2952 {
2955 machine_mode mode;
2956 machine_mode mode2;
2965 /* Emit a libcall to libgcc. */
2967 /* Mode of the 2nd argument must match that of an int. */
2985 }
2987 /* Expand expression EXP which is a call to the strlen builtin. Return
2988 NULL_RTX if we failed and the caller should emit a normal call, otherwise
2989 try to get the result in TARGET, if convenient. */
2991 static rtx
2993 machine_mode target_mode)
2994 {
2999 rtx pat;
3000 tree len;
3002 rtx src_reg;
3004 machine_mode insn_mode;
3008 /* If the length can be computed at compile-time, return it. */
3013 /* If the length can be computed at compile-time and is constant
3014 integer, but there are side-effects in src, evaluate
3015 src for side-effects, then return len.
3016 E.g. x = strlen (i++ ? "xfoo" + 1 : "bar");
3017 can be optimized into: i++; x = 3; */
3020 {
3023 }
3027 /* If SRC is not a pointer type, don't do this operation inline. */
3031 /* Bail out if we can't compute strlen in the right mode. */
3033 {
3037 }
3041 /* Make a place to hold the source address. We will not expand
3042 the actual source until we are sure that the expansion will
3043 not fail -- there are trees that cannot be expanded twice. */
3046 /* Mark the beginning of the strlen sequence so we can emit the
3047 source operand later. */
3057 /* Check to see if the argument was declared attribute nonstring
3058 and if so, issue a warning since at this point it's not known
3059 to be nul-terminated. */
3062 /* Now that we are assured of success, expand the source. */
3066 {
3067 #ifdef POINTERS_EXTEND_UNSIGNED
3070 POINTERS_EXTEND_UNSIGNED);
3071 #endif
3073 }
3079 else
3082 /* Return the value in the proper mode for this function. */
3087 else
3091 }
3093 /* Expand call EXP to the strnlen built-in, returning the result
3094 and setting it in TARGET. Otherwise return NULL_RTX on failure. */
3096 static rtx
3098 {
3115 /* FIXME: Change c_strlen() to return sizetype instead of ssizetype
3116 so these conversions aren't necessary. */
3117 c_strlen_data lendata = { };
3123 {
3127 "%K%qD specified bound %E "
3134 {
3135 /* Clear EXACT if LEN may be less than SRC suggests,
3136 such as in
3137 strnlen (&a[i], sizeof a)
3138 where the value of i is unknown. Unless i's value is
3139 zero, the call is unsafe because the bound is greater. */
3143 }
3149 {
3150 location_t warnloc
3154 exact
3160 {
3165 }
3166 }
3173 }
3186 "%K%qD specified bound [%wu, %wu] "
3193 {
3197 }
3203 {
3204 location_t warnloc
3208 exact
3214 {
3218 }
3219 }
3229 }
3231 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
3232 bytes from constant string DATA + OFFSET and return it as target
3233 constant. */
3235 static rtx
3237 scalar_int_mode mode)
3238 {
3246 }
3248 /* LEN specify length of the block of memcpy/memset operation.
3249 Figure out its range and put it into MIN_SIZE/MAX_SIZE.
3250 In some cases we can make very likely guess on max size, then we
3251 set it into PROBABLE_MAX_SIZE. */
3253 static void
3258 {
3260 {
3263 }
3264 else
3265 {
3269 /* Determine bounds from the type. */
3272 else
3277 else
3283 {
3288 }
3290 {
3291 /* Anti range 0...N lets us to determine minimal size to N+1. */
3293 {
3296 }
3297 /* Code like
3299 int n;
3300 if (n < 100)
3301 memcpy (a, b, n)
3303 Produce anti range allowing negative values of N. We still
3304 can use the information and make a guess that N is not negative.
3305 */
3308 }
3309 }
3313 }
3315 /* Try to verify that the sizes and lengths of the arguments to a string
3316 manipulation function given by EXP are within valid bounds and that
3317 the operation does not lead to buffer overflow or read past the end.
3318 Arguments other than EXP may be null. When non-null, the arguments
3319 have the following meaning:
3320 DST is the destination of a copy call or NULL otherwise.
3321 SRC is the source of a copy call or NULL otherwise.
3322 DSTWRITE is the number of bytes written into the destination obtained
3323 from the user-supplied size argument to the function (such as in
3324 memcpy(DST, SRCs, DSTWRITE) or strncpy(DST, DRC, DSTWRITE).
3325 MAXREAD is the user-supplied bound on the length of the source sequence
3326 (such as in strncat(d, s, N). It specifies the upper limit on the number
3327 of bytes to write. If NULL, it's taken to be the same as DSTWRITE.
3328 SRCSTR is the source string (such as in strcpy(DST, SRC)) when the
3329 expression EXP is a string function call (as opposed to a memory call
3330 like memcpy). As an exception, SRCSTR can also be an integer denoting
3331 the precomputed size of the source string or object (for functions like
3332 memcpy).
3333 DSTSIZE is the size of the destination object specified by the last
3334 argument to the _chk builtins, typically resulting from the expansion
3335 of __builtin_object_size (such as in __builtin___strcpy_chk(DST, SRC,
3336 DSTSIZE).
3338 When DSTWRITE is null LEN is checked to verify that it doesn't exceed
3339 SIZE_MAX.
3341 If the call is successfully verified as safe return true, otherwise
3342 return false. */
3344 bool
3347 {
3350 /* The size of the largest object is half the address space, or
3351 PTRDIFF_MAX. (This is way too permissive.) */
3354 /* Either the length of the source string for string functions or
3355 the size of the source object for raw memory functions. */
3360 /* Set to true when the exact number of bytes written by a string
3361 function like strcpy is not known and the only thing that is
3362 known is that it must be at least one (for the terminating nul). */
3365 {
3366 /* SRCSTR is normally a pointer to string but as a special case
3367 it can be an integer denoting the length of a string. */
3369 {
3370 /* Try to determine the range of lengths the source string
3371 refers to. If it can be determined and is less than
3372 the upper bound given by MAXREAD add one to it for
3373 the terminating nul. Otherwise, set it to one for
3374 the same reason, or to MAXREAD as appropriate. */
3375 c_strlen_data lendata = { };
3380 {
3383 else
3394 }
3395 else
3396 {
3399 }
3400 }
3401 else
3403 }
3406 {
3407 /* When the only available piece of data is the object size
3408 there is nothing to do. */
3412 /* Otherwise, when the length of the source sequence is known
3413 (as with strlen), set DSTWRITE to it. */
3416 }
3426 /* First check the number of bytes to be written against the maximum
3427 object size. */
3431 {
3440 warned = (func
3442 "%K%qD specified size %E "
3446 "%Kspecified size %E "
3449 else
3450 warned = (func
3452 "%K%qD specified size between %E and %E "
3457 "%Kspecified size between %E and %E "
3464 }
3466 /* The number of bytes to write is "exact" if DSTWRITE is non-null,
3467 constant, and in range of unsigned HOST_WIDE_INT. */
3470 /* Next check the number of bytes to be written against the destination
3471 object size. */
3473 {
3478 || (dstwrite
3481 {
3490 {
3491 /* This is a call to strcpy with a destination of 0 size
3492 and a source of unknown length. The call will write
3493 at least one byte past the end of the destination. */
3494 warned = (func
3496 "%K%qD writing %E or more bytes into "
3497 "a region of size %E overflows "
3501 "%Kwriting %E or more bytes into "
3502 "a region of size %E overflows "
3505 }
3507 warned = (func
3509 "%K%qD writing %E byte into a region "
3511 "%K%qD writing %E bytes into a region "
3515 "%Kwriting %E byte into a region "
3517 "%Kwriting %E bytes into a region "
3521 {
3522 /* Avoid printing the upper bound if it's invalid. */
3523 warned = (func
3525 "%K%qD writing %E or more bytes into "
3526 "a region of size %E overflows "
3530 "%Kwriting %E or more bytes into "
3531 "a region of size %E overflows "
3534 }
3535 else
3536 warned = (func
3538 "%K%qD writing between %E and %E bytes "
3539 "into a region of size %E overflows "
3542 dstsize)
3544 "%Kwriting between %E and %E bytes "
3545 "into a region of size %E overflows "
3548 dstsize));
3552 /* Return error when an overflow has been detected. */
3554 }
3555 }
3557 /* Check the maximum length of the source sequence against the size
3558 of the destination object if known, or against the maximum size
3559 of an object. */
3561 {
3564 {
3569 {
3575 /* Warn about crazy big sizes first since that's more
3576 likely to be meaningful than saying that the bound
3577 is greater than the object size if both are big. */
3579 warned = (func
3581 "%K%qD specified bound %E "
3585 "%Kspecified bound %E "
3588 else
3589 warned = (func
3591 "%K%qD specified bound between "
3592 "%E and %E exceeds maximum object "
3597 "%Kspecified bound between "
3598 "%E and %E exceeds maximum object "
3605 }
3608 {
3615 warned = (func
3617 "%K%qD specified bound %E "
3622 "%Kspecified bound %E "
3625 else
3626 warned = (func
3628 "%K%qD specified bound between %E "
3633 "%Kspecified bound between %E "
3635 exp,
3641 }
3642 }
3643 }
3645 /* Check for reading past the end of SRC. */
3650 {
3659 warned = (func
3669 {
3670 /* Avoid printing the upper bound if it's invalid. */
3671 warned = (func
3673 "%K%qD reading %E or more bytes from a region "
3677 "%Kreading %E or more bytes from a region "
3680 }
3681 else
3682 warned = (func
3684 "%K%qD reading between %E and %E bytes from "
3688 "%Kreading between %E and %E bytes from "
3695 }
3698 }
3700 /* If STMT is a call to an allocation function, returns the constant
3701 size of the object allocated by the call represented as sizetype.
3702 If nonnull, sets RNG1[] to the range of the size. */
3704 tree
3707 {
3711 tree allocfntype;
3714 else
3723 {
3728 }
3733 {
3744 {
3748 }
3749 }
3754 /* If RNG1 is not set, use the buffer. */
3764 /* To handle ranges do the math in wide_int and return the product
3765 of the upper bounds as a constant. Ignore anti-ranges. */
3771 /* Extend to the maximum precision to avoid overflow. */
3778 /* Compute products of both bounds for the caller but return the lesser
3779 of SIZE_MAX and the product of the upper bounds as a constant. */
3784 {
3787 }
3790 }
3792 /* Helper for compute_objsize. Returns the constant size of the DEST
3793 if it refers to a variable or field and sets *PDECL to the DECL and
3794 *POFF to zero. Otherwise returns null for other nodes. */
3796 static tree
3798 {
3803 {
3808 }
3811 {
3814 /* Only return constant sizes for now while callers depend on it. */
3817 }
3820 }
3822 /* Helper to compute the size of the object referenced by the DEST
3823 expression which must have pointer type, using Object Size type
3824 OSTYPE (only the least significant 2 bits are used).
3825 Returns an estimate of the size of the object represented as
3826 a sizetype constant if successful or NULL when the size cannot
3827 be determined.
3828 When the referenced object involves a non-constant offset in some
3829 range the returned value represents the largest size given the
3830 smallest non-negative offset in the range.
3831 If nonnull, sets *PDECL to the decl of the referenced subobject
3832 if it can be determined, or to null otherwise. Likewise, when
3833 POFF is nonnull *POFF is set to the offset into *PDECL.
3835 The function is intended for diagnostics and should not be used
3836 to influence code generation or optimization. */
3838 tree
3841 {
3850 /* Only the two least significant bits are meaningful. */
3854 /* Except for overly permissive calls to memcpy and other raw
3855 memory functions with zero OSTYPE, detect the size from simple
3856 DECLs first to more reliably than compute_builtin_object_size
3857 set *PDECL and *POFF. */
3866 {
3869 {
3870 /* If STMT is a call to an allocation function get the size
3871 from its argument(s). If successful, also set *PDECL to
3872 DEST for the caller to include in diagnostics. */
3874 {
3878 }
3880 }
3889 {
3890 /* compute_builtin_object_size fails for addresses with
3891 non-constant offsets. Try to determine the range of
3892 such an offset here and use it to adjust the constant
3893 size. */
3896 {
3898 {
3902 /* Ignore negative offsets for now. For others,
3903 use the lower bound as the most optimistic
3904 estimate of the (remaining) size. */
3906 ;
3907 else
3908 {
3910 {
3914 }
3915 else
3921 }
3922 }
3923 }
3926 {
3932 {
3935 /* Ignore negative offsets for now. For others,
3936 use the lower bound as the most optimistic
3937 estimate of the (remaining)size. */
3939 ;
3940 else
3941 {
3942 /* FIXME: For now, since the offset is non-constant,
3943 clear *POFF to keep it from being "misused."
3944 Eventually *POFF will need to become a range that
3945 can be properly added to the outer offset if it
3946 too is one. */
3952 }
3953 }
3954 }
3955 }
3958 }
3960 /* Unless computing the largest size (for memcpy and other raw memory
3961 functions), try to determine the size of the object from its type. */
3967 {
3971 {
3972 /* Give up for MEM_REFs of vector types; those may be synthesized
3973 from multiple assignments to consecutive data members. See PR
3974 93200.
3975 FIXME: Deal with this more generally, e.g., by marking up such
3976 MEM_REFs at the time they're created. */
3980 }
3983 {
3984 /* If the declaration of the destination object is known
3985 to have zero size, return zero. */
3991 /* A valid offset into a declared object cannot be negative.
3992 A zero size with a zero "inner" offset is still zero size
3993 regardless of the "other" offset OFF. */
4004 /* Convert to the same precision to keep wide_int from "helpfully"
4005 crashing whenever it sees other arguments. */
4010 /* Adjust SIZE either up or down by the sum of *POFF and OFF
4011 above. */
4013 {
4016 {
4017 /* Adjust the offset by the low bound of the array
4018 domain (normally zero but 1 in Fortran). */
4022 }
4024 /* Convert the array index into a byte offset. */
4028 {
4032 }
4033 else
4035 }
4040 {
4041 /* If the "inner" offset is unknown and the "outer" offset
4042 is either negative or less than SIZE, return the size
4043 minus the offset. This may be overly optimistic in
4044 the first case if the inner offset happens to be less
4045 than the absolute value of the outer offset. */
4051 }
4053 /* Convert to the same precision to keep wide_int from "helpfuly"
4054 crashing whenever it sees other argumments. */
4062 {
4066 }
4069 {
4073 /* Return the difference between the size and the offset
4074 or zero if the offset is greater. */
4080 }
4086 {
4087 enum value_range_kind rng
4091 }
4092 else
4106 }
4109 }
4111 /* Try simple DECLs not handled above. */
4125 {
4128 }
4131 }
4133 /* Helper to determine and check the sizes of the source and the destination
4134 of calls to __builtin_{bzero,memcpy,mempcpy,memset} calls. EXP is the
4135 call expression, DEST is the destination argument, SRC is the source
4136 argument or null, and LEN is the number of bytes. Use Object Size type-0
4137 regardless of the OPT_Wstringop_overflow_ setting. Return true on success
4138 (no overflow or invalid sizes), false otherwise. */
4140 static bool
4142 {
4143 /* For functions like memset and memcpy that operate on raw memory
4144 try to determine the size of the largest source and destination
4145 object using type-0 Object Size regardless of the object size
4146 type specified by the option. */
4152 }
4154 /* Validate memchr arguments without performing any expansion.
4155 Return NULL_RTX. */
4157 static rtx
4159 {
4167 /* Diagnose calls where the specified length exceeds the size
4168 of the object. */
4170 {
4174 }
4177 }
4179 /* Expand a call EXP to the memcpy builtin.
4180 Return NULL_RTX if we failed, the caller should emit a normal call,
4181 otherwise try to get the result in TARGET, if convenient (and in
4182 mode MODE if that's convenient). */
4184 static rtx
4186 {
4199 }
4201 /* Check a call EXP to the memmove built-in for validity.
4202 Return NULL_RTX on both success and failure. */
4204 static rtx
4206 {
4219 }
4221 /* Expand a call EXP to the mempcpy builtin.
4222 Return NULL_RTX if we failed; the caller should emit a normal call,
4223 otherwise try to get the result in TARGET, if convenient (and in
4224 mode MODE if that's convenient). */
4226 static rtx
4228 {
4237 /* Policy does not generally allow using compute_objsize (which
4238 is used internally by check_memop_size) to change code generation
4239 or drive optimization decisions.
4241 In this instance it is safe because the code we generate has
4242 the same semantics regardless of the return value of
4243 check_memop_sizes. Exactly the same amount of data is copied
4244 and the return value is exactly the same in both cases.
4246 Furthermore, check_memop_size always uses mode 0 for the call to
4247 compute_objsize, so the imprecise nature of compute_objsize is
4248 avoided. */
4250 /* Avoid expanding mempcpy into memcpy when the call is determined
4251 to overflow the buffer. This also prevents the same overflow
4252 from being diagnosed again when expanding memcpy. */
4258 }
4260 /* Helper function to do the actual work for expand of memory copy family
4261 functions (memcpy, mempcpy, stpcpy). Expansing should assign LEN bytes
4262 of memory from SRC to DEST and assign to TARGET if convenient. Return
4263 value is based on RETMODE argument. */
4265 static rtx
4269 {
4282 /* If DEST is not a pointer type, call the normal function. */
4286 /* If either SRC is not a pointer type, don't do this
4287 operation in-line. */
4304 /* If SRC is a string constant and block move would be done by
4305 pieces, we can avoid loading the string from memory and only
4306 stored the computed constants. This works in the overlap
4307 (memmove) case as well because store_by_pieces just generates a
4308 series of stores of constants from the string constant returned
4309 by c_getstr(). */
4316 {
4318 builtin_memcpy_read_str,
4324 }
4329 /* Copy word part most expediently. */
4336 && !might_overlap
4345 /* Bail out when a mempcpy call would be expanded as libcall and when
4346 we have a target that provides a fast implementation
4347 of mempcpy routine. */
4355 {
4358 }
4361 {
4363 /* stpcpy pointer to last byte. */
4366 }
4369 }
4371 static rtx
4374 {
4377 }
4379 /* Expand into a movstr instruction, if one is available. Return NULL_RTX if
4380 we failed, the caller should emit a normal call, otherwise try to
4381 get the result in TARGET, if convenient.
4382 Return value is based on RETMODE argument. */
4384 static rtx
4386 {
4388 rtx dest_mem;
4389 rtx src_mem;
4397 {
4400 }
4410 {
4412 /* movstr is supposed to set end to the address of the NUL
4413 terminator. If the caller requested a mempcpy-like return value,
4414 adjust it. */
4416 {
4420 }
4421 }
4423 }
4425 /* Do some very basic size validation of a call to the strcpy builtin
4426 given by EXP. Return NULL_RTX to have the built-in expand to a call
4427 to the library function. */
4429 static rtx
4431 {
4439 /* Detect unterminated source (only). */
4443 /* There is no way here to determine the length of the string in
4444 the destination to which the SRC string is being appended so
4445 just diagnose cases when the souce string is longer than
4446 the destination object. */
4451 destsize);
4454 }
4456 /* Expand expression EXP, which is a call to the strcpy builtin. Return
4457 NULL_RTX if we failed the caller should emit a normal call, otherwise
4458 try to get the result in TARGET, if convenient (and in mode MODE if that's
4459 convenient). */
4461 static rtx
4463 {
4471 {
4475 }
4478 {
4479 /* Check to see if the argument was declared attribute nonstring
4480 and if so, issue a warning since at this point it's not known
4481 to be nul-terminated. */
4485 }
4488 }
4490 /* Helper function to do the actual work for expand_builtin_strcpy. The
4491 arguments to the builtin_strcpy call DEST and SRC are broken out
4492 so that this can also be called without constructing an actual CALL_EXPR.
4493 The other arguments and return value are the same as for
4494 expand_builtin_strcpy. */
4496 static rtx
4498 {
4499 /* Detect strcpy calls with unterminated arrays.. */
4501 {
4502 /* NONSTR refers to the non-nul terminated constant array. */
4506 }
4509 }
4511 /* Expand a call EXP to the stpcpy builtin.
4512 Return NULL_RTX if we failed the caller should emit a normal call,
4513 otherwise try to get the result in TARGET, if convenient (and in
4514 mode MODE if that's convenient). */
4516 static rtx
4518 {
4529 {
4533 }
4535 /* If return value is ignored, transform stpcpy into strcpy. */
4537 {
4541 }
4542 else
4543 {
4545 rtx ret;
4547 /* Ensure we get an actual string whose length can be evaluated at
4548 compile-time, not an expression containing a string. This is
4549 because the latter will potentially produce pessimized code
4550 when used to produce the return value. */
4551 c_strlen_data lendata = { };
4569 {
4573 {
4577 {
4579 {
4582 else
4584 }
4593 }
4594 }
4595 }
4599 }
4600 }
4602 /* Expand a call EXP to the stpcpy builtin and diagnose uses of nonstring
4603 arguments while being careful to avoid duplicate warnings (which could
4604 be issued if the expander were to expand the call, resulting in it
4605 being emitted in expand_call(). */
4607 static rtx
4609 {
4611 {
4612 /* The call has been successfully expanded. Check for nonstring
4613 arguments and issue warnings as appropriate. */
4616 }
4619 }
4621 /* Check a call EXP to the stpncpy built-in for validity.
4622 Return NULL_RTX on both success and failure. */
4624 static rtx
4626 {
4632 /* The source and destination of the call. */
4636 /* The exact number of bytes to write (not the maximum). */
4641 /* The size of the destination object. */
4647 }
4649 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
4650 bytes from constant string DATA + OFFSET and return it as target
4651 constant. */
4653 rtx
4655 scalar_int_mode mode)
4656 {
4663 }
4665 /* Helper to check the sizes of sequences and the destination of calls
4666 to __builtin_strncat and __builtin___strncat_chk. Returns true on
4667 success (no overflow or invalid sizes), false otherwise. */
4669 static bool
4671 {
4676 /* Try to determine the range of lengths that the source expression
4677 refers to. */
4678 c_strlen_data lendata = { };
4681 /* Try to verify that the destination is big enough for the shortest
4682 string. */
4685 {
4686 /* If it hasn't been provided by __strncat_chk, try to determine
4687 the size of the destination object into which the source is
4688 being copied. */
4690 }
4692 /* Add one for the terminating nul. */
4695 size_one_node)
4698 /* The strncat function copies at most MAXREAD bytes and always appends
4699 the terminating nul so the specified upper bound should never be equal
4700 to (or greater than) the size of the destination. */
4703 {
4712 }
4720 /* The number of bytes to write is LEN but check_access will also
4721 check SRCLEN if LEN's value isn't known. */
4723 objsize);
4724 }
4726 /* Similar to expand_builtin_strcat, do some very basic size validation
4727 of a call to the strcpy builtin given by EXP. Return NULL_RTX to have
4728 the built-in expand to a call to the library function. */
4730 static rtx
4732 {
4740 /* The upper bound on the number of bytes to write. */
4743 /* Detect unterminated source (only). */
4747 /* The length of the source sequence. */
4750 /* Try to determine the range of lengths that the source expression
4751 refers to. Since the lengths are only used for warning and not
4752 for code generation disable strict mode below. */
4755 {
4756 c_strlen_data lendata = { };
4759 }
4761 /* Try to verify that the destination is big enough for the shortest
4762 string. First try to determine the size of the destination object
4763 into which the source is being copied. */
4766 /* Add one for the terminating nul. */
4767 tree srclen = (maxlen
4769 size_one_node)
4772 /* The strncat function copies at most MAXREAD bytes and always appends
4773 the terminating nul so the specified upper bound should never be equal
4774 to (or greater than) the size of the destination. */
4777 {
4786 }
4794 /* The number of bytes to write is SRCLEN. */
4798 }
4800 /* Expand expression EXP, which is a call to the strncpy builtin. Return
4801 NULL_RTX if we failed the caller should emit a normal call. */
4803 static rtx
4805 {
4813 /* The number of bytes to write (not the maximum). */
4819 /* The length of the source sequence. */
4823 {
4827 /* The number of bytes to write is LEN but check_access will also
4828 check SLEN if LEN's value isn't known. */
4830 destsize);
4831 }
4833 /* We must be passed a constant len and src parameter. */
4839 /* We're required to pad with trailing zeros if the requested
4840 len is greater than strlen(s2)+1. In that case try to
4841 use store_by_pieces, if it fails, punt. */
4843 {
4846 rtx dest_mem;
4850 builtin_strncpy_read_str,
4857 builtin_strncpy_read_str,
4859 RETURN_BEGIN);
4863 }
4866 }
4868 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
4869 bytes from constant string DATA + OFFSET and return it as target
4870 constant. */
4872 rtx
4874 scalar_int_mode mode)
4875 {
4882 }
4884 /* Callback routine for store_by_pieces. Return the RTL of a register
4885 containing GET_MODE_SIZE (MODE) consecutive copies of the unsigned
4886 char value given in the RTL register data. For example, if mode is
4887 4 bytes wide, return the RTL for 0x01010101*data. */
4889 static rtx
4891 scalar_int_mode mode)
4892 {
4908 }
4910 /* Expand expression EXP, which is a call to the memset builtin. Return
4911 NULL_RTX if we failed the caller should emit a normal call, otherwise
4912 try to get the result in TARGET, if convenient (and in mode MODE if that's
4913 convenient). */
4915 static rtx
4917 {
4929 }
4931 /* Helper function to do the actual work for expand_builtin_memset. The
4932 arguments to the builtin_memset call DEST, VAL, and LEN are broken out
4933 so that this can also be called without constructing an actual CALL_EXPR.
4934 The other arguments and return value are the same as for
4935 expand_builtin_memset. */
4937 static rtx
4940 {
4943 machine_mode val_mode;
4955 /* If DEST is not a pointer type, don't do this operation in-line. */
4966 /* If the LEN parameter is zero, return DEST. */
4968 {
4969 /* Evaluate and ignore VAL in case it has side-effects. */
4972 }
4974 /* Stabilize the arguments in case we fail. */
4986 {
4987 rtx val_rtx;
4992 /* Assume that we can memset by pieces if we can store
4993 * the coefficients by pieces (in the required modes).
4994 * We can't pass builtin_memset_gen_str as that emits RTL. */
5000 {
5005 }
5009 probable_max_size))
5015 }
5021 {
5028 RETURN_BEGIN);
5033 probable_max_size))
5039 }
5047 probable_max_size);
5050 {
5053 }
5057 do_libcall:
5066 else
5071 }
5073 /* Expand expression EXP, which is a call to the bzero builtin. Return
5074 NULL_RTX if we failed the caller should emit a normal call. */
5076 static rtx
5078 {
5087 /* New argument list transforming bzero(ptr x, int y) to
5088 memset(ptr x, int 0, size_t y). This is done this way
5089 so that if it isn't expanded inline, we fallback to
5090 calling bzero instead of memset. */
5098 }
5100 /* Try to expand cmpstr operation ICODE with the given operands.
5101 Return the result rtx on success, otherwise return null. */
5103 static rtx
5105 HOST_WIDE_INT align)
5106 {
5120 }
5122 /* Expand expression EXP, which is a call to the memcmp built-in function.
5123 Return NULL_RTX if we failed and the caller should emit a normal call,
5124 otherwise try to get the result in TARGET, if convenient.
5125 RESULT_EQ is true if we can relax the returned value to be either zero
5126 or nonzero, without caring about the sign. */
5128 static rtx
5130 {
5141 /* Diagnose calls where the specified length exceeds the size of either
5142 object. */
5148 {
5153 }
5155 /* If the specified length exceeds the size of either object,
5156 call the function. */
5160 /* Due to the performance benefit, always inline the calls first
5161 when result_eq is false. */
5165 {
5169 }
5177 /* If we don't have POINTER_TYPE, call the function. */
5185 /* Set MEM_SIZE as appropriate. */
5187 {
5190 }
5196 {
5200 }
5202 /* If SRC is a string constant and block move would be done
5203 by pieces, we can avoid loading the string from memory
5204 and only stored the computed constants. */
5216 {
5217 /* Return the value in the proper mode for this function. */
5222 {
5225 }
5228 }
5231 }
5233 /* Expand expression EXP, which is a call to the strcmp builtin. Return NULL_RTX
5234 if we failed the caller should emit a normal call, otherwise try to get
5235 the result in TARGET, if convenient. */
5237 static rtx
5239 {
5250 /* Due to the performance benefit, always inline the calls first. */
5264 /* If we don't have POINTER_TYPE, call the function. */
5268 /* Stabilize the arguments in case gen_cmpstr(n)si fail. */
5275 /* Try to call cmpstrsi. */
5280 /* Try to determine at least one length and call cmpstrnsi. */
5282 {
5283 tree len;
5284 rtx arg3_rtx;
5294 /* If we don't have a constant length for the first, use the length
5295 of the second, if we know it. We don't require a constant for
5296 this case; some cost analysis could be done if both are available
5297 but neither is constant. For now, assume they're equally cheap,
5298 unless one has side effects. If both strings have constant lengths,
5299 use the smaller. */
5315 else
5318 /* If both arguments have side effects, we cannot optimize. */
5320 {
5322 result = expand_cmpstrn_or_cmpmem
5325 }
5326 }
5330 {
5331 /* Check to see if the argument was declared attribute nonstring
5332 and if so, issue a warning since at this point it's not known
5333 to be nul-terminated. */
5336 /* Return the value in the proper mode for this function. */
5344 }
5346 /* Expand the library call ourselves using a stabilized argument
5347 list to avoid re-evaluating the function's arguments twice. */
5352 }
5354 /* Expand expression EXP, which is a call to the strncmp builtin. Return
5355 NULL_RTX if we failed the caller should emit a normal call, otherwise try to get
5356 the result in TARGET, if convenient. */
5358 static rtx
5360 ATTRIBUTE_UNUSED machine_mode mode)
5361 {
5374 /* Due to the performance benefit, always inline the calls first. */
5380 /* If c_strlen can determine an expression for one of the string
5381 lengths, and it doesn't have side effects, then emit cmpstrnsi
5382 using length MIN(strlen(string)+1, arg3). */
5387 tree len;
5404 /* If we don't have a constant length for the first, use the length
5405 of the second, if we know it. If neither string is constant length,
5406 use the given length argument. We don't require a constant for
5407 this case; some cost analysis could be done if both are available
5408 but neither is constant. For now, assume they're equally cheap,
5409 unless one has side effects. If both strings have constant lengths,
5410 use the smaller. */
5428 else
5431 /* If we are not using the given length, we must incorporate it here.
5432 The actual new length parameter will be MIN(len,arg3) in this case. */
5434 {
5437 }
5447 {
5448 /* Check to see if the argument was declared attribute nonstring
5449 and if so, issue a warning since at this point it's not known
5450 to be nul-terminated. */
5453 /* Return the value in the proper mode for this function. */
5461 }
5463 /* Expand the library call ourselves using a stabilized argument
5464 list to avoid re-evaluating the function's arguments twice. */
5469 }
5471 /* Expand a call to __builtin_saveregs, generating the result in TARGET,
5472 if that's convenient. */
5474 rtx
5476 {
5477 rtx val;
5480 /* Don't do __builtin_saveregs more than once in a function.
5481 Save the result of the first call and reuse it. */
5485 /* When this function is called, it means that registers must be
5486 saved on entry to this function. So we migrate the call to the
5487 first insn of this function. */
5491 /* Do whatever the machine needs done in this case. */
5499 /* Put the insns after the NOTE that starts the function. If this
5500 is inside a start_sequence, make the outer-level insn chain current, so
5501 the code is placed at the start of the function. */
5507 }
5509 /* Expand a call to __builtin_next_arg. */
5511 static rtx
5513 {
5514 /* Checking arguments is already done in fold_builtin_next_arg
5515 that must be called before this function. */
5520 }
5522 /* Make it easier for the backends by protecting the valist argument
5523 from multiple evaluations. */
5525 static tree
5527 {
5530 /* The current way of determining the type of valist is completely
5531 bogus. We should have the information on the va builtin instead. */
5536 {
5540 /* For this case, the backends will be expecting a pointer to
5541 vatype, but it's possible we've actually been given an array
5542 (an actual TARGET_CANONICAL_VA_LIST_TYPE (valist)).
5543 So fix it. */
5545 {
5548 }
5549 }
5550 else
5551 {
5555 {
5561 }
5567 }
5570 }
5572 /* The "standard" definition of va_list is void*. */
5574 tree
5576 {
5578 }
5580 /* The "standard" abi va_list is va_list_type_node. */
5582 tree
5584 {
5586 }
5588 /* The "standard" type of va_list is va_list_type_node. */
5590 tree
5592 {
5599 {
5600 /* If va_list is an array type, the argument may have decayed
5601 to a pointer type, e.g. by being passed to another function.
5602 In that case, unwrap both types so that we can compare the
5603 underlying records. */
5606 {
5609 }
5610 }
5615 }
5617 /* The "standard" implementation of va_start: just assign `nextarg' to
5618 the variable. */
5620 void
5622 {
5625 }
5627 /* Expand EXP, a call to __builtin_va_start. */
5629 static rtx
5631 {
5632 rtx nextarg;
5633 tree valist;
5637 {
5640 }
5650 else
5654 }
5656 /* Expand EXP, a call to __builtin_va_end. */
5658 static rtx
5660 {
5663 /* Evaluate for side effects, if needed. I hate macros that don't
5664 do that. */
5669 }
5671 /* Expand EXP, a call to __builtin_va_copy. We do this as a
5672 builtin rather than just as an assignment in stdarg.h because of the
5673 nastiness of array-type va_list types. */
5675 static rtx
5677 {
5690 {
5694 }
5695 else
5696 {
5699 /* Evaluate to pointers. */
5708 /* "Dereference" to BLKmode memories. */
5716 /* Copy. */
5718 }
5721 }
5723 /* Expand a call to one of the builtin functions __builtin_frame_address or
5724 __builtin_return_address. */
5726 static rtx
5728 {
5729 /* The argument must be a nonnegative integer constant.
5730 It counts the number of frames to scan up the stack.
5731 The value is either the frame pointer value or the return
5732 address saved in that frame. */
5734 /* Warning about missing arg was already issued. */
5737 {
5740 }
5741 else
5742 {
5743 /* Number of frames to scan up the stack. */
5748 /* Some ports cannot access arbitrary stack frames. */
5750 {
5753 }
5756 {
5757 /* Warn since no effort is made to ensure that any frame
5758 beyond the current one exists or can be safely reached. */
5761 }
5763 /* For __builtin_frame_address, return what we've got. */
5771 }
5772 }
5774 /* Expand EXP, a call to the alloca builtin. Return NULL_RTX if we
5775 failed and the caller should emit a normal call. */
5777 static rtx
5779 {
5780 rtx op0;
5781 rtx result;
5784 HOST_WIDE_INT max_size;
5787 bool valid_arglist
5790 VOID_TYPE)
5801 || (!alloca_for_var
5804 ))
5805 {
5806 /* -Walloca-larger-than and -Wvla-larger-than settings of
5807 less than HOST_WIDE_INT_MAX override the more general
5808 -Walloc-size-larger-than so unless either of the former
5809 options is smaller than the last one (wchich would imply
5810 that the call was already checked), check the alloca
5811 arguments for overflow. */
5815 }
5817 /* Compute the argument. */
5820 /* Compute the alignment. */
5822 ? BIGGEST_ALIGNMENT
5825 /* Compute the maximum size. */
5830 /* Allocate the desired space. If the allocation stems from the declaration
5831 of a variable-sized object, it cannot accumulate. */
5832 result
5836 /* Dynamic allocations for variables are recorded during gimplification. */
5841 }
5843 /* Emit a call to __asan_allocas_unpoison call in EXP. Add to second argument
5844 of the call virtual_stack_dynamic_rtx - stack_pointer_rtx, which is the
5845 STACK_DYNAMIC_OFFSET value. See motivation for this in comment to
5846 handle_builtin_stack_restore function. */
5848 static rtx
5850 {
5857 OPTAB_LIB_WIDEN);
5860 OPTAB_LIB_WIDEN);
5865 }
5867 /* Expand a call to bswap builtin in EXP.
5868 Return NULL_RTX if a normal call should be emitted rather than expanding the
5869 function in-line. If convenient, the result should be placed in TARGET.
5870 SUBTARGET may be used as the target for computing one of EXP's operands. */
5872 static rtx
5874 rtx subtarget)
5875 {
5876 tree arg;
5877 rtx op0;
5895 }
5897 /* Expand a call to a unary builtin in EXP.
5898 Return NULL_RTX if a normal call should be emitted rather than expanding the
5899 function in-line. If convenient, the result should be placed in TARGET.
5900 SUBTARGET may be used as the target for computing one of EXP's operands. */
5902 static rtx
5905 {
5906 rtx op0;
5911 /* Compute the argument. */
5913 (subtarget
5917 /* Compute op, into TARGET if possible.
5918 Set TARGET to wherever the result comes back. */
5924 }
5926 /* Expand a call to __builtin_expect. We just return our argument
5927 as the builtin_expect semantic should've been already executed by
5928 tree branch prediction pass. */
5930 static rtx
5932 {
5933 tree arg;
5940 /* When guessing was done, the hints should be already stripped away. */
5944 }
5946 /* Expand a call to __builtin_expect_with_probability. We just return our
5947 argument as the builtin_expect semantic should've been already executed by
5948 tree branch prediction pass. */
5950 static rtx
5952 {
5953 tree arg;
5960 /* When guessing was done, the hints should be already stripped away. */
5964 }
5967 /* Expand a call to __builtin_assume_aligned. We just return our first
5968 argument as the builtin_assume_aligned semantic should've been already
5969 executed by CCP. */
5971 static rtx
5973 {
5977 EXPAND_NORMAL);
5982 }
5984 void
5986 {
5988 {
5990 /* For trap insns when not accumulating outgoing args force
5991 REG_ARGS_SIZE note to prevent crossjumping of calls with
5992 different args sizes. */
5995 }
5996 else
5997 {
6001 }
6004 }
6006 /* Expand a call to __builtin_unreachable. We do nothing except emit
6007 a barrier saying that control flow will not pass here.
6009 It is the responsibility of the program being compiled to ensure
6010 that control flow does never reach __builtin_unreachable. */
6011 static void
6013 {
6015 }
6017 /* Expand EXP, a call to fabs, fabsf or fabsl.
6018 Return NULL_RTX if a normal call should be emitted rather than expanding
6019 the function inline. If convenient, the result should be placed
6020 in TARGET. SUBTARGET may be used as the target for computing
6021 the operand. */
6023 static rtx
6025 {
6026 machine_mode mode;
6027 tree arg;
6028 rtx op0;
6038 }
6040 /* Expand EXP, a call to copysign, copysignf, or copysignl.
6041 Return NULL is a normal call should be emitted rather than expanding the
6042 function inline. If convenient, the result should be placed in TARGET.
6043 SUBTARGET may be used as the target for computing the operand. */
6045 static rtx
6047 {
6049 tree arg;
6061 }
6063 /* Expand a call to __builtin___clear_cache. */
6065 static rtx
6067 {
6069 {
6070 #ifdef CLEAR_INSN_CACHE
6071 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
6072 does something. Just do the default expansion to a call to
6073 __clear_cache(). */
6075 #else
6076 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
6077 does nothing. There is no need to call it. Do nothing. */
6080 }
6082 /* We have a "clear_cache" insn, and it will handle everything. */
6086 /* We must not expand to a library call. If we did, any
6087 fallback library function in libgcc that might contain a call to
6088 __builtin___clear_cache() would recurse infinitely. */
6090 {
6093 }
6096 {
6109 }
6111 }
6113 /* Given a trampoline address, make sure it satisfies TRAMPOLINE_ALIGNMENT. */
6115 static rtx
6117 {
6120 /* If we don't need too much alignment, we'll have been guaranteed
6121 proper alignment by get_trampoline_type. */
6125 /* Round address up to desired boundary. */
6136 }
6138 static rtx
6140 {
6156 /* If ONSTACK, the TRAMP argument should be the address of a field
6157 within the local function's FRAME decl. Either way, let's see if
6158 we can fill in the MEM_ATTRs for this memory. */
6162 /* Creator of a heap trampoline is responsible for making sure the
6163 address is aligned to at least STACK_BOUNDARY. Normally malloc
6164 will ensure this anyhow. */
6167 {
6171 }
6173 /* The FUNC argument should be the address of the nested function.
6174 Extract the actual function decl to pass to the hook. */
6181 /* Generate insns to initialize the trampoline. */
6185 {
6191 }
6194 }
6196 static rtx
6198 {
6199 rtx tramp;
6210 }
6212 /* Expand a call to the builtin descriptor initialization routine.
6213 A descriptor is made up of a couple of pointers to the static
6214 chain and the code entry in this order. */
6216 static rtx
6218 {
6223 VOID_TYPE))
6238 /* Generate insns to initialize the descriptor. */
6244 }
6246 /* Expand a call to the builtin descriptor adjustment routine. */
6248 static rtx
6250 {
6251 rtx tramp;
6258 /* Unalign the descriptor to allow runtime identification. */
6263 }
6265 /* Expand the call EXP to the built-in signbit, signbitf or signbitl
6266 function. The function first checks whether the back end provides
6267 an insn to implement signbit for the respective mode. If not, it
6268 checks whether the floating point format of the value is such that
6269 the sign bit can be extracted. If that is not the case, error out.
6270 EXP is the expression that is a call to the builtin function; if
6271 convenient, the result should be placed in TARGET. */
6272 static rtx
6274 {
6276 scalar_float_mode fmode;
6278 tree arg;
6281 rtx temp;
6294 /* Expand the argument yielding a RTX expression. */
6297 /* Check if the back end provides an insn that handles signbit for the
6298 argument's mode. */
6301 {
6307 }
6309 /* For floating point formats without a sign bit, implement signbit
6310 as "ARG < 0.0". */
6313 {
6314 /* But we can't do this if the format supports signed zero. */
6320 }
6323 {
6326 }
6327 else
6328 {
6330 /* Handle targets with different FP word orders. */
6333 else
6337 }
6339 /* Force the intermediate word_mode (or narrower) result into a
6340 register. This avoids attempting to create paradoxical SUBREGs
6341 of floating point modes below. */
6344 /* If the bitpos is within the "result mode" lowpart, the operation
6345 can be implement with a single bitwise AND. Otherwise, we need
6346 a right shift and an AND. */
6349 {
6357 }
6358 else
6359 {
6360 /* Perform a logical right shift to place the signbit in the least
6361 significant bit, then truncate the result to the desired mode
6362 and mask just this bit. */
6367 }
6370 }
6372 /* Expand fork or exec calls. TARGET is the desired target of the
6373 call. EXP is the call. FN is the
6374 identificator of the actual function. IGNORE is nonzero if the
6375 value is to be ignored. */
6377 static rtx
6379 {
6381 tree call;
6384 {
6385 /* Detect unterminated path. */
6389 /* Also detect unterminated first argument. */
6391 {
6399 }
6400 }
6403 /* If we are not profiling, just call the function. */
6407 /* Otherwise call the wrapper. This should be equivalent for the rest of
6408 compiler, so the code does not diverge, and the wrapper may run the
6409 code necessary for keeping the profiling sane. */
6412 {
6443 }
6455 }
6458 \f
6459 /* Reconstitute a mode for a __sync intrinsic operation. Since the type of
6460 the pointer in these functions is void*, the tree optimizers may remove
6461 casts. The mode computed in expand_builtin isn't reliable either, due
6462 to __sync_bool_compare_and_swap.
6464 FCODE_DIFF should be fcode - base, where base is the FOO_1 code for the
6465 group of builtins. This gives us log2 of the mode size. */
6469 {
6470 /* The size is not negotiable, so ask not to get BLKmode in return
6471 if the target indicates that a smaller size would be better. */
6473 }
6475 /* Expand the memory expression LOC and return the appropriate memory operand
6476 for the builtin_sync operations. */
6478 static rtx
6480 {
6490 /* Note that we explicitly do not want any alias information for this
6491 memory, so that we kill all other live memories. Otherwise we don't
6492 satisfy the full barrier semantics of the intrinsic. */
6499 /* The alignment needs to be at least according to that of the mode. */
6506 }
6508 /* Make sure an argument is in the right mode.
6509 EXP is the tree argument.
6510 MODE is the mode it should be in. */
6512 static rtx
6514 {
6515 rtx val;
6516 machine_mode old_mode;
6519 /* If VAL is promoted to a wider mode, convert it back to MODE. Take care
6520 of CONST_INTs, where we know the old_mode only from the call argument. */
6527 }
6530 /* Expand the __sync_xxx_and_fetch and __sync_fetch_and_xxx intrinsics.
6531 EXP is the CALL_EXPR. CODE is the rtx code
6532 that corresponds to the arithmetic or logical operation from the name;
6533 an exception here is that NOT actually means NAND. TARGET is an optional
6534 place for us to store the results; AFTER is true if this is the
6535 fetch_and_xxx form. */
6537 static rtx
6540 rtx target)
6541 {
6546 {
6553 {
6582 }
6583 }
6585 /* Expand the operands. */
6590 after);
6591 }
6593 /* Expand the __sync_val_compare_and_swap and __sync_bool_compare_and_swap
6594 intrinsics. EXP is the CALL_EXPR. IS_BOOL is
6595 true if this is the boolean form. TARGET is a place for us to store the
6596 results; this is NOT optional if IS_BOOL is true. */
6598 static rtx
6601 {
6605 /* Expand the operands. */
6612 {
6615 else
6617 }
6620 MEMMODEL_SYNC_SEQ_CST))
6624 }
6626 /* Expand the __sync_lock_test_and_set intrinsic. Note that the most
6627 general form is actually an atomic exchange, and some targets only
6628 support a reduced form with the second argument being a constant 1.
6629 EXP is the CALL_EXPR; TARGET is an optional place for us to store
6630 the results. */
6632 static rtx
6634 rtx target)
6635 {
6638 /* Expand the operands. */
6643 }
6645 /* Expand the __sync_lock_release intrinsic. EXP is the CALL_EXPR. */
6647 static void
6649 {
6650 rtx mem;
6652 /* Expand the operands. */
6656 }
6658 /* Given an integer representing an ``enum memmodel'', verify its
6659 correctness and return the memory model enum. */
6661 static enum memmodel
6663 {
6664 rtx op;
6666 location_t loc
6669 /* If the parameter is not a constant, it's a run time value so we'll just
6670 convert it to MEMMODEL_SEQ_CST to avoid annoying runtime checking. */
6680 {
6684 }
6686 /* Should never see a user explicit SYNC memodel model, so >= LAST works. */
6688 {
6692 }
6694 /* Workaround for Bugzilla 59448. GCC doesn't track consume properly, so
6695 be conservative and promote consume to acquire. */
6700 }
6702 /* Expand the __atomic_exchange intrinsic:
6703 TYPE __atomic_exchange (TYPE *object, TYPE desired, enum memmodel)
6704 EXP is the CALL_EXPR.
6705 TARGET is an optional place for us to store the results. */
6707 static rtx
6709 {
6718 /* Expand the operands. */
6723 }
6725 /* Expand the __atomic_compare_exchange intrinsic:
6726 bool __atomic_compare_exchange (TYPE *object, TYPE *expect,
6727 TYPE desired, BOOL weak,
6728 enum memmodel success,
6729 enum memmodel failure)
6730 EXP is the CALL_EXPR.
6731 TARGET is an optional place for us to store the results. */
6733 static rtx
6735 rtx target)
6736 {
6740 tree weak;
6742 location_t loc
6749 {
6751 "failure memory model cannot be stronger than success "
6754 }
6757 {
6759 "invalid failure memory model for "
6763 }
6769 /* Expand the operands. */
6785 /* Lest the rtl backend create a race condition with an imporoper store
6786 to memory, always create a new pseudo for OLDVAL. */
6793 /* Conditionally store back to EXPECT, lest we create a race condition
6794 with an improper store to memory. */
6795 /* ??? With a rearrangement of atomics at the gimple level, we can handle
6796 the normal case where EXPECT is totally private, i.e. a register. At
6797 which point the store can be unconditional. */
6805 }
6807 /* Helper function for expand_ifn_atomic_compare_exchange - expand
6808 internal ATOMIC_COMPARE_EXCHANGE call into __atomic_compare_exchange_N
6809 call. The weak parameter must be dropped to match the expected parameter
6810 list and the expected argument changed from value to pointer to memory
6811 slot. */
6813 static void
6815 {
6831 /* Skip the boolean weak parameter. */
6834 /* At present we only have BUILT_IN_ATOMIC_COMPARE_EXCHANGE_{1,2,4,8,16}. */
6837 built_in_function fncode
6842 fndecl);
6847 {
6854 }
6855 }
6857 /* Expand IFN_ATOMIC_COMPARE_EXCHANGE internal function. */
6859 void
6861 {
6867 tree lhs;
6869 location_t loc
6876 {
6878 "failure memory model cannot be stronger than success "
6881 }
6884 {
6886 "invalid failure memory model for "
6890 }
6893 {
6896 }
6898 /* Expand the operands. */
6911 {
6914 }
6918 {
6924 }
6925 }
6927 /* Expand the __atomic_load intrinsic:
6928 TYPE __atomic_load (TYPE *object, enum memmodel)
6929 EXP is the CALL_EXPR.
6930 TARGET is an optional place for us to store the results. */
6932 static rtx
6934 {
6935 rtx mem;
6940 {
6941 location_t loc
6946 }
6951 /* Expand the operand. */
6955 }
6958 /* Expand the __atomic_store intrinsic:
6959 void __atomic_store (TYPE *object, TYPE desired, enum memmodel)
6960 EXP is the CALL_EXPR.
6961 TARGET is an optional place for us to store the results. */
6963 static rtx
6965 {
6972 {
6973 location_t loc
6978 }
6983 /* Expand the operands. */
6988 }
6990 /* Expand the __atomic_fetch_XXX intrinsic:
6991 TYPE __atomic_fetch_XXX (TYPE *object, TYPE val, enum memmodel)
6992 EXP is the CALL_EXPR.
6993 TARGET is an optional place for us to store the results.
6994 CODE is the operation, PLUS, MINUS, ADD, XOR, or IOR.
6995 FETCH_AFTER is true if returning the result of the operation.
6996 FETCH_AFTER is false if returning the value before the operation.
6997 IGNORE is true if the result is not used.
6998 EXT_CALL is the correct builtin for an external call if this cannot be
6999 resolved to an instruction sequence. */
7001 static rtx
7005 {
7008 tree fndecl;
7009 tree addr;
7013 /* Expand the operands. */
7017 /* Only try generating instructions if inlining is turned on. */
7019 {
7023 }
7025 /* Return if a different routine isn't needed for the library call. */
7029 /* Change the call to the specified function. */
7037 /* If we will emit code after the call, the call cannot be a tail call.
7038 If it is emitted as a tail call, a barrier is emitted after it, and
7039 then all trailing code is removed. */
7043 /* Expand the call here so we can emit trailing code. */
7046 /* Replace the original function just in case it matters. */
7049 /* Then issue the arithmetic correction to return the right result. */
7051 {
7053 {
7055 OPTAB_LIB_WIDEN);
7057 }
7058 else
7060 OPTAB_LIB_WIDEN);
7061 }
7063 }
7065 /* Expand IFN_ATOMIC_BIT_TEST_AND_* internal function. */
7067 void
7069 {
7077 optab optab;
7089 {
7104 }
7107 {
7114 }
7136 {
7141 }
7142 else
7144 OPTAB_DIRECT);
7147 }
7149 /* Expand an atomic clear operation.
7150 void _atomic_clear (BOOL *obj, enum memmodel)
7151 EXP is the call expression. */
7153 static rtx
7155 {
7156 machine_mode mode;
7165 {
7166 location_t loc
7171 }
7173 /* Try issuing an __atomic_store, and allow fallback to __sync_lock_release.
7174 Failing that, a store is issued by __atomic_store. The only way this can
7175 fail is if the bool type is larger than a word size. Unlikely, but
7176 handle it anyway for completeness. Assume a single threaded model since
7177 there is no atomic support in this case, and no barriers are required. */
7182 }
7184 /* Expand an atomic test_and_set operation.
7185 bool _atomic_test_and_set (BOOL *obj, enum memmodel)
7186 EXP is the call expression. */
7188 static rtx
7190 {
7191 rtx mem;
7193 machine_mode mode;
7200 }
7203 /* Return true if (optional) argument ARG1 of size ARG0 is always lock free on
7204 this architecture. If ARG1 is NULL, use typical alignment for size ARG0. */
7206 static tree
7208 {
7210 machine_mode mode;
7216 /* We need a corresponding integer mode for the access to be lock-free. */
7224 {
7227 /* Either this argument is null, or it's a fake pointer encoding
7228 the alignment of the object. */
7234 else
7236 }
7237 else
7238 {
7241 /* This function is usually invoked and folded immediately by the front
7242 end before anything else has a chance to look at it. The pointer
7243 parameter at this point is usually cast to a void *, so check for that
7244 and look past the cast. */
7254 /* Get the underlying type of the object. */
7257 }
7259 /* If the object has smaller alignment, the lock free routines cannot
7260 be used. */
7264 /* Check if a compare_and_swap pattern exists for the mode which represents
7265 the required size. The pattern is not allowed to fail, so the existence
7266 of the pattern indicates support is present. Also require that an
7267 atomic load exists for the required size. */
7270 else
7272 }
7274 /* Return true if the parameters to call EXP represent an object which will
7275 always generate lock free instructions. The first argument represents the
7276 size of the object, and the second parameter is a pointer to the object
7277 itself. If NULL is passed for the object, then the result is based on
7278 typical alignment for an object of the specified size. Otherwise return
7279 false. */
7281 static rtx
7283 {
7284 tree size;
7289 {
7292 }
7298 }
7300 /* Return a one or zero if it can be determined that object ARG1 of size ARG
7301 is lock free on this architecture. */
7303 static tree
7305 {
7309 /* If it isn't always lock free, don't generate a result. */
7314 }
7316 /* Return true if the parameters to call EXP represent an object which will
7317 always generate lock free instructions. The first argument represents the
7318 size of the object, and the second parameter is a pointer to the object
7319 itself. If NULL is passed for the object, then the result is based on
7320 typical alignment for an object of the specified size. Otherwise return
7321 NULL*/
7323 static rtx
7325 {
7326 tree size;
7331 {
7334 }
7339 /* If the value is known at compile time, return the RTX for it. */
7345 }
7347 /* Expand the __atomic_thread_fence intrinsic:
7348 void __atomic_thread_fence (enum memmodel)
7349 EXP is the CALL_EXPR. */
7351 static void
7353 {
7356 }
7358 /* Expand the __atomic_signal_fence intrinsic:
7359 void __atomic_signal_fence (enum memmodel)
7360 EXP is the CALL_EXPR. */
7362 static void
7364 {
7367 }
7369 /* Expand the __sync_synchronize intrinsic. */
7371 static void
7373 {
7375 }
7377 static rtx
7379 {
7385 {
7387 /* If the target is not sutitable then create a new target. */
7395 }
7398 }
7400 static void
7402 {
7408 {
7415 }
7417 }
7419 \f
7420 /* Emit code to restore the current value of stack. */
7422 static void
7424 {
7436 }
7438 /* Emit code to save the current value of stack. */
7440 static rtx
7442 {
7447 }
7449 /* Emit code to get the openacc gang, worker or vector id or size. */
7451 static rtx
7453 {
7455 rtx fallback_retval;
7458 {
7471 }
7474 {
7477 }
7481 {
7484 }
7488 {
7496 }
7505 {
7508 }
7516 }
7518 /* Expand a string compare operation using a sequence of char comparison
7519 to get rid of the calling overhead, with result going to TARGET if
7520 that's convenient.
7522 VAR_STR is the variable string source;
7523 CONST_STR is the constant string source;
7524 LENGTH is the number of chars to compare;
7525 CONST_STR_N indicates which source string is the constant string;
7526 IS_MEMCMP indicates whether it's a memcmp or strcmp.
7528 to: (assume const_str_n is 2, i.e., arg2 is a constant string)
7530 target = (int) (unsigned char) var_str[0]
7531 - (int) (unsigned char) const_str[0];
7532 if (target != 0)
7533 goto ne_label;
7534 ...
7535 target = (int) (unsigned char) var_str[length - 2]
7536 - (int) (unsigned char) const_str[length - 2];
7537 if (target != 0)
7538 goto ne_label;
7539 target = (int) (unsigned char) var_str[length - 1]
7540 - (int) (unsigned char) const_str[length - 1];
7541 ne_label:
7542 */
7544 static rtx
7548 {
7550 rtx var_rtx_array
7557 scalar_int_mode unit_mode
7563 {
7564 var_rtx
7578 }
7586 }
7588 /* Inline expansion a call to str(n)cmp, with result going to
7589 TARGET if that's convenient.
7590 If the call is not been inlined, return NULL_RTX. */
7591 static rtx
7593 {
7599 /* Do NOT apply this inlining expansion when optimizing for size or
7600 optimization level below 2. */
7608 /* On a target where the type of the call (int) has same or narrower presicion
7609 than unsigned char, give up the inlining expansion. */
7625 /* If neither strings is constant string, the call is not qualify. */
7629 /* For strncmp, if the length is not a const, not qualify. */
7631 {
7634 else
7636 }
7651 else
7660 /* If the length of the comparision is larger than the threshold,
7661 do nothing. */
7663 param_builtin_string_cmp_inline_length)
7668 /* Now, start inline expansion the call. */
7672 }
7674 /* Expand a call to __builtin_speculation_safe_value_<N>. MODE
7675 represents the size of the first argument to that call, or VOIDmode
7676 if the argument is a pointer. IGNORE will be true if the result
7677 isn't used. */
7678 static rtx
7681 {
7688 {
7691 }
7695 /* An optional second argument can be used as a failsafe value on
7696 some machines. If it isn't present, then the failsafe value is
7697 assumed to be 0. */
7699 {
7702 }
7703 else
7706 /* If the result isn't used, the behavior is undefined. It would be
7707 nice to emit a warning here, but path splitting means this might
7708 happen with legitimate code. So simply drop the builtin
7709 expansion in that case; we've handled any side-effects above. */
7713 /* If we don't have a suitable target, create one to hold the result. */
7721 }
7723 /* Expand an expression EXP that calls a built-in function,
7724 with result going to TARGET if that's convenient
7725 (and in mode MODE if that's convenient).
7726 SUBTARGET may be used as the target for computing one of EXP's operands.
7727 IGNORE is nonzero if the value is to be ignored. */
7729 rtx
7732 {
7740 /* When ASan is enabled, we don't want to expand some memory/string
7741 builtins and rely on libsanitizer's hooks. This allows us to avoid
7742 redundant checks and be sure, that possible overflow will be detected
7743 by ASan. */
7749 /* When not optimizing, generate calls to library functions for a certain
7750 set of builtins. */
7764 /* The built-in function expanders test for target == const0_rtx
7765 to determine whether the function's result will be ignored. */
7769 /* If the result of a pure or const built-in function is ignored, and
7770 none of its arguments are volatile, we can avoid expanding the
7771 built-in call and just evaluate the arguments for side-effects. */
7775 {
7777 tree arg;
7778 call_expr_arg_iterator iter;
7782 {
7785 }
7788 {
7792 }
7793 }
7796 {
7814 /* Just do a normal library call if we were unable to fold
7815 the values. */
7892 /* __builtin_apply (FUNCTION, ARGUMENTS, ARGSIZE) invokes
7893 FUNCTION with a copy of the parameters described by
7894 ARGUMENTS, and ARGSIZE. It returns a block of memory
7895 allocated on the stack into which is stored all the registers
7896 that might possibly be used for returning the result of a
7897 function. ARGUMENTS is the value returned by
7898 __builtin_apply_args. ARGSIZE is the number of bytes of
7899 arguments that must be copied. ??? How should this value be
7900 computed? We'll also need a safe worst case value for varargs
7901 functions. */
7908 else
7909 {
7917 }
7919 /* __builtin_return (RESULT) causes the function to return the
7920 value described by RESULT. RESULT is address of the block of
7921 memory returned by __builtin_apply. */
7931 /* All valid uses of __builtin_va_arg_pack () are removed during
7932 inlining. */
7937 /* All valid uses of __builtin_va_arg_pack_len () are removed during
7938 inlining. */
7942 /* Return the address of the first anonymous stack arg. */
7964 /* Returns the address of the area where the structure is returned.
7965 0 otherwise. */
7971 else
7974 CASE_BUILT_IN_ALLOCA:
8090 {
8093 }
8162 /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it
8163 back to a BUILT_IN_STRCMP. Remember to delete the 3rd paramater
8164 when changing it to a strcmp call. */
8170 /* Change this call back to a BUILT_IN_STRCMP. */
8174 /* Delete the last parameter. */
8181 /* FALLTHROUGH */
8189 /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it
8190 back to a BUILT_IN_STRNCMP. */
8196 /* Change it back to a BUILT_IN_STRNCMP. */
8199 /* FALLTHROUGH */
8214 {
8217 }
8221 /* This should have been lowered to the builtins below. */
8225 /* __builtin_setjmp_setup is passed a pointer to an array of five words
8226 and the receiver label. */
8228 {
8234 /* This is copied from the handling of non-local gotos. */
8236 nonlocal_goto_handler_labels
8238 nonlocal_goto_handler_labels);
8239 /* ??? Do not let expand_label treat us as such since we would
8240 not want to be both on the list of non-local labels and on
8241 the list of forced labels. */
8244 }
8248 /* __builtin_setjmp_receiver is passed the receiver label. */
8250 {
8256 }
8259 /* __builtin_longjmp is passed a pointer to an array of five words.
8260 It's similar to the C library longjmp function but works with
8261 __builtin_setjmp above. */
8264 {
8270 {
8273 }
8277 }
8286 /* This updates the setjmp buffer that is its argument with the value
8287 of the current stack pointer. */
8290 {
8291 rtx buf_addr
8296 }
8316 /* Various hooks for the DWARF 2 __throw routine. */
8322 #ifdef DWARF2_UNWIND_INFO
8328 #endif
8530 mode = get_builtin_sync_mode
8542 mode = get_builtin_sync_mode
8589 {
8593 mode =
8599 /* If this is turned into an external library call, the weak parameter
8600 must be dropped to match the expected parameter list. */
8605 /* Skip the boolean weak parameter. */
8610 }
8639 {
8649 }
8655 {
8665 }
8671 {
8681 }
8687 {
8697 }
8703 {
8713 }
8719 {
8729 }
8866 /* Do library call, if we failed to expand the builtin when
8867 folding. */
8887 }
8889 /* The switch statement above can drop through to cause the function
8890 to be called normally. */
8892 }
8894 /* Determine whether a tree node represents a call to a built-in
8895 function. If the tree T is a call to a built-in function with
8896 the right number of arguments of the appropriate types, return
8897 the DECL_FUNCTION_CODE of the call, e.g. BUILT_IN_SQRT.
8898 Otherwise the return value is END_BUILTINS. */
8900 enum built_in_function
8902 {
8905 const_call_expr_arg_iterator iter;
8917 {
8918 /* If a function doesn't take a variable number of arguments,
8919 the last element in the list will have type `void'. */
8922 {
8926 }
8935 {
8938 }
8940 {
8943 }
8945 {
8948 }
8950 {
8953 }
8954 else
8956 }
8958 /* Variable-length argument list. */
8960 }
8962 /* Fold a call to __builtin_constant_p, if we know its argument ARG will
8963 evaluate to a constant. */
8965 static tree
8967 {
8968 /* We return 1 for a numeric type that's known to be a constant
8969 value at compile-time or for an aggregate type that's a
8970 literal constant. */
8973 /* If we know this is a constant, emit the constant of one. */
8979 {
8986 }
8988 /* If this expression has side effects, show we don't know it to be a
8989 constant. Likewise if it's a pointer or aggregate type since in
8990 those case we only want literals, since those are only optimized
8991 when generating RTL, not later.
8992 And finally, if we are compiling an initializer, not code, we
8993 need to return a definite result now; there's not going to be any
8994 more optimization done. */
8999 || folding_initializer
9004 }
9006 /* Create builtin_expect or builtin_expect_with_probability
9007 with PRED and EXPECTED as its arguments and return it as a truthvalue.
9008 Fortran FE can also produce builtin_expect with PREDICTOR as third argument.
9009 builtin_expect_with_probability instead uses third argument as PROBABILITY
9010 value. */
9012 static tree
9015 {
9030 else
9032 predictor);
9036 }
9038 /* Fold a call to builtin_expect with arguments ARG0, ARG1, ARG2, ARG3. Return
9039 NULL_TREE if no simplification is possible. */
9041 tree
9043 tree arg3)
9044 {
9048 /* Distribute the expected value over short-circuiting operators.
9049 See through the cast from truthvalue_type_node to long. */
9056 /* If this is a builtin_expect within a builtin_expect keep the
9057 inner one. See through a comparison against a constant. It
9058 might have been added to create a thruthvalue. */
9074 {
9084 }
9086 /* If the argument isn't invariant then there's nothing else we can do. */
9090 /* If we expect that a comparison against the argument will fold to
9091 a constant return the constant. In practice, this means a true
9092 constant or the address of a non-weak symbol. */
9096 {
9097 do
9098 {
9100 }
9105 }
9107 /* Otherwise, ARG0 already has the proper type for the return value. */
9109 }
9111 /* Fold a call to __builtin_classify_type with argument ARG. */
9113 static tree
9115 {
9120 }
9122 /* Fold a call to __builtin_strlen with argument ARG. */
9124 static tree
9126 {
9129 else
9130 {
9131 c_strlen_data lendata = { };
9141 {
9147 }
9150 }
9151 }
9153 /* Fold a call to __builtin_inf or __builtin_huge_val. */
9155 static tree
9157 {
9158 REAL_VALUE_TYPE real;
9160 /* __builtin_inff is intended to be usable to define INFINITY on all
9161 targets. If an infinity is not available, INFINITY expands "to a
9162 positive constant of type float that overflows at translation
9163 time", footnote "In this case, using INFINITY will violate the
9164 constraint in 6.4.4 and thus require a diagnostic." (C99 7.12#4).
9165 Thus we pedwarn to ensure this constraint violation is
9166 diagnosed. */
9172 }
9174 /* Fold function call to builtin sincos, sincosf, or sincosl. Return
9175 NULL_TREE if no simplification can be made. */
9177 static tree
9180 {
9181 tree type;
9191 /* Calculate the result when the argument is a constant. */
9196 /* Canonicalize sincos to cexpi. */
9198 {
9201 }
9203 {
9210 }
9222 }
9224 /* Fold function call to builtin memcmp with arguments ARG1 and ARG2.
9225 Return NULL_TREE if no simplification can be made. */
9227 static tree
9229 {
9235 /* If the LEN parameter is zero, return zero. */
9240 /* If ARG1 and ARG2 are the same (and not volatile), return zero. */
9244 /* If len parameter is one, return an expression corresponding to
9245 (*(const unsigned char*)arg1 - (const unsigned char*)arg2). */
9247 {
9249 tree cst_uchar_ptr_node
9252 tree ind1
9256 cst_uchar_ptr_node,
9257 arg1)));
9258 tree ind2
9262 cst_uchar_ptr_node,
9263 arg2)));
9265 }
9268 }
9270 /* Fold a call to builtin isascii with argument ARG. */
9272 static tree
9274 {
9277 else
9278 {
9279 /* Transform isascii(c) -> ((c & ~0x7f) == 0). */
9285 }
9286 }
9288 /* Fold a call to builtin toascii with argument ARG. */
9290 static tree
9292 {
9296 /* Transform toascii(c) -> (c & 0x7f). */
9299 }
9301 /* Fold a call to builtin isdigit with argument ARG. */
9303 static tree
9305 {
9308 else
9309 {
9310 /* Transform isdigit(c) -> (unsigned)(c) - '0' <= 9. */
9311 /* According to the C standard, isdigit is unaffected by locale.
9312 However, it definitely is affected by the target character set. */
9313 unsigned HOST_WIDE_INT target_digit0
9324 }
9325 }
9327 /* Fold a call to fabs, fabsf or fabsl with argument ARG. */
9329 static tree
9331 {
9337 }
9339 /* Fold a call to abs, labs, llabs or imaxabs with argument ARG. */
9341 static tree
9343 {
9349 }
9351 /* Fold a call to builtin carg(a+bi) -> atan2(b,a). */
9353 static tree
9355 {
9358 {
9362 {
9367 }
9368 }
9371 }
9373 /* Fold a call to builtin frexp, we can assume the base is 2. */
9375 static tree
9377 {
9388 /* Proceed if a valid pointer type was passed in. */
9390 {
9395 {
9397 /* For +-0, return (*exp = 0, +-0). */
9403 /* For +-NaN or +-Inf, *exp is unspecified, return arg0. */
9406 {
9407 /* Since the frexp function always expects base 2, and in
9408 GCC normalized significands are already in the range
9409 [0.5, 1.0), we have exactly what frexp wants. */
9414 }
9418 }
9420 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
9424 }
9427 }
9429 /* Fold a call to builtin modf. */
9431 static tree
9433 {
9444 /* Proceed if a valid pointer type was passed in. */
9446 {
9451 {
9454 /* For +-NaN or +-0, return (*arg1 = arg0, arg0). */
9458 /* For +-Inf, return (*arg1 = arg0, +-0). */
9464 /* Return (*arg1 = trunc(arg0), arg0-trunc(arg0)). */
9467 /* If the original number was negative and already
9468 integral, then the fractional part is -0.0. */
9472 }
9474 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
9480 }
9483 }
9485 /* Given a location LOC, an interclass builtin function decl FNDECL
9486 and its single argument ARG, return an folded expression computing
9487 the same, or NULL_TREE if we either couldn't or didn't want to fold
9488 (the latter happen if there's an RTL instruction available). */
9490 static tree
9492 {
9493 machine_mode mode;
9505 /* If there is no optab, try generic code. */
9507 {
9508 tree result;
9511 {
9512 /* isinf(x) -> isgreater(fabs(x),DBL_MAX). */
9515 REAL_VALUE_TYPE r;
9519 {
9520 /* NaN and Inf are encoded in the high-order double value
9521 only. The low-order value is not significant. */
9525 }
9532 }
9535 {
9536 /* isfinite(x) -> islessequal(fabs(x),DBL_MAX). */
9539 REAL_VALUE_TYPE r;
9543 {
9544 /* NaN and Inf are encoded in the high-order double value
9545 only. The low-order value is not significant. */
9549 }
9555 /*result = fold_build2_loc (loc, UNGT_EXPR,
9556 TREE_TYPE (TREE_TYPE (fndecl)),
9557 fold_build1_loc (loc, ABS_EXPR, type, arg),
9558 build_real (type, r));
9559 result = fold_build1_loc (loc, TRUTH_NOT_EXPR,
9560 TREE_TYPE (TREE_TYPE (fndecl)),
9561 result);*/
9563 }
9565 {
9566 /* isnormal(x) -> isgreaterequal(fabs(x),DBL_MIN) &
9567 islessequal(fabs(x),DBL_MAX). */
9577 {
9578 /* Use double to test the normal range of IBM extended
9579 precision. Emin for IBM extended precision is
9580 different to emin for IEEE double, being 53 higher
9581 since the low double exponent is at least 53 lower
9582 than the high double exponent. */
9586 }
9598 {
9599 /* Testing the high end of the range is done just using
9600 the high double, using the same test as isfinite().
9601 For the subnormal end of the range we first test the
9602 high double, then if its magnitude is equal to the
9603 limit of 0x1p-969, we test whether the low double is
9604 non-zero and opposite sign to the high double. */
9620 integer_type_node,
9626 }
9627 else
9628 {
9629 tree const isge_fn
9632 }
9636 }
9639 }
9642 }
9644 /* Fold a call to __builtin_isnan(), __builtin_isinf, __builtin_finite.
9645 ARG is the argument for the call. */
9647 static tree
9649 {
9656 {
9664 {
9665 /* isinf_sign(x) -> isinf(x) ? (signbit(x) ? -1 : 1) : 0 */
9666 /* In a boolean context, GCC will fold the inner COND_EXPR to
9667 1. So e.g. "if (isinf_sign(x))" would be folded to just
9668 "if (isinf(x) ? 1 : 0)" which becomes "if (isinf(x))". */
9676 {
9689 integer_zero_node);
9690 }
9693 }
9706 {
9709 {
9710 /* NaN and Inf are encoded in the high-order double value
9711 only. The low-order value is not significant. */
9713 }
9714 }
9720 }
9721 }
9723 /* Fold a call to __builtin_fpclassify(int, int, int, int, int, ...).
9724 This builtin will generate code to return the appropriate floating
9725 point classification depending on the value of the floating point
9726 number passed in. The possible return values must be supplied as
9727 int arguments to the call in the following order: FP_NAN, FP_INFINITE,
9728 FP_NORMAL, FP_SUBNORMAL and FP_ZERO. The ellipses is for exactly
9729 one floating point argument which is "type generic". */
9731 static tree
9733 {
9736 machine_mode mode;
9737 REAL_VALUE_TYPE r;
9740 /* Verify the required arguments in the original call. */
9760 /* fpclassify(x) ->
9761 isnan(x) ? FP_NAN :
9762 (fabs(x) == Inf ? FP_INFINITE :
9763 (fabs(x) >= DBL_MIN ? FP_NORMAL :
9764 (x == 0 ? FP_ZERO : FP_SUBNORMAL))). */
9778 {
9784 }
9787 {
9790 }
9793 }
9795 /* Fold a call to an unordered comparison function such as
9796 __builtin_isgreater(). FNDECL is the FUNCTION_DECL for the function
9797 being called and ARG0 and ARG1 are the arguments for the call.
9798 UNORDERED_CODE and ORDERED_CODE are comparison codes that give
9799 the opposite of the desired result. UNORDERED_CODE is used
9800 for modes that can hold NaNs and ORDERED_CODE is used for
9801 the rest. */
9803 static tree
9807 {
9821 /* Choose the wider of two real types. */
9833 {
9837 }
9842 }
9844 /* Fold __builtin_{,s,u}{add,sub,mul}{,l,ll}_overflow, either into normal
9845 arithmetics if it can never overflow, or into internal functions that
9846 return both result of arithmetics and overflowed boolean flag in
9847 a complex integer result, or some other check for overflow.
9848 Similarly fold __builtin_{add,sub,mul}_overflow_p to just the overflow
9849 checking part of that. */
9851 static tree
9854 {
9856 /* The code of the expression corresponding to the built-in. */
9861 {
9864 /* FALLTHRU */
9877 /* FALLTHRU */
9890 /* FALLTHRU */
9903 }
9905 /* For the "generic" overloads, the first two arguments can have different
9906 types and the last argument determines the target type to use to check
9907 for overflow. The arguments of the other overloads all have the same
9908 type. */
9911 /* For the __builtin_{add,sub,mul}_overflow_p builtins, when the first two
9912 arguments are constant, attempt to fold the built-in call into a constant
9913 expression indicating whether or not it detected an overflow. */
9917 /* Perform the computation in the target type and check for overflow. */
9921 arg2);
9925 {
9933 }
9934 else
9935 {
9943 }
9949 tree store
9952 }
9954 /* Fold a call to __builtin_FILE to a constant string. */
9958 {
9960 {
9961 /* The documentation says this builtin is equivalent to the preprocessor
9962 __FILE__ macro so it appears appropriate to use the same file prefix
9963 mappings. */
9966 }
9969 }
9971 /* Fold a call to __builtin_FUNCTION to a constant string. */
9975 {
9982 }
9984 /* Fold a call to __builtin_LINE to an integer constant. */
9988 {
9990 }
9992 /* Fold a call to built-in function FNDECL with 0 arguments.
9993 This function returns NULL_TREE if no simplification was possible. */
9995 static tree
9997 {
10001 {
10027 }
10029 }
10031 /* Fold a call to built-in function FNDECL with 1 argument, ARG0.
10032 This function returns NULL_TREE if no simplification was possible. */
10034 static tree
10036 {
10047 {
10049 {
10052 /* Gimplification will pull the CALL_EXPR for the builtin out of
10053 an if condition. When not optimizing, we'll not CSE it back.
10054 To avoid link error types of regressions, return false now. */
10059 }
10115 {
10120 }
10126 {
10131 }
10152 }
10156 }
10158 /* Folds a call EXPR (which may be null) to built-in function FNDECL
10159 with 2 arguments, ARG0 and ARG1. This function returns NULL_TREE
10160 if no simplification was possible. */
10162 static tree
10164 {
10176 {
10220 NOP_EXPR);
10222 /* We do the folding for va_start in the expander. */
10237 }
10239 }
10241 /* Fold a call to built-in function FNDECL with 3 arguments, ARG0, ARG1,
10242 and ARG2.
10243 This function returns NULL_TREE if no simplification was possible. */
10245 static tree
10248 {
10262 {
10311 }
10313 }
10315 /* Folds a call EXPR (which may be null) to built-in function FNDECL.
10316 ARGS is an array of NARGS arguments. IGNORE is true if the result
10317 of the function call is ignored. This function returns NULL_TREE
10318 if no simplification was possible. */
10320 static tree
10323 {
10327 {
10343 }
10345 {
10349 }
10351 }
10353 /* Construct a new CALL_EXPR to FNDECL using the tail of the argument
10354 list ARGS along with N new arguments in NEWARGS. SKIP is the number
10355 of arguments in ARGS to be omitted. OLDNARGS is the number of
10356 elements in ARGS. */
10358 static tree
10361 {
10366 {
10374 }
10375 else
10379 }
10381 /* Return true if FNDECL shouldn't be folded right now.
10382 If a built-in function has an inline attribute always_inline
10383 wrapper, defer folding it after always_inline functions have
10384 been inlined, otherwise e.g. -D_FORTIFY_SOURCE checking
10385 might not be performed. */
10387 bool
10389 {
10392 && cfun
10395 }
10397 /* A wrapper function for builtin folding that prevents warnings for
10398 "statement without effect" and the like, caused by removing the
10399 call node earlier than the warning is generated. */
10401 tree
10403 {
10407 /* If CALL_EXPR_VA_ARG_PACK is set, the arguments aren't finalized
10408 yet. Defer folding until we see all the arguments
10409 (after inlining). */
10411 {
10414 /* Before gimplification CALL_EXPR_VA_ARG_PACK is not set, but
10415 instead last argument is __builtin_va_arg_pack (). Defer folding
10416 even in that case, until arguments are finalized. */
10418 {
10422 }
10430 else
10431 {
10436 }
10437 }
10439 }
10441 /* Fold a CALL_EXPR with type TYPE with FN as the function expression.
10442 N arguments are passed in the array ARGARRAY. Return a folded
10443 expression or NULL_TREE if no simplification was possible. */
10445 tree
10447 tree fn,
10450 {
10457 {
10458 /* If last argument is __builtin_va_arg_pack (), arguments to this
10459 function are not finalized yet. Defer folding until they are. */
10461 {
10465 }
10470 else
10472 }
10475 }
10477 /* Construct a new CALL_EXPR using the tail of the argument list of EXP
10478 along with N new arguments specified as the "..." parameters. SKIP
10479 is the number of arguments in EXP to be omitted. This function is used
10480 to do varargs-to-varargs transformations. */
10482 static tree
10484 {
10486 tree t;
10494 }
10496 /* Validate a single argument ARG against a tree code CODE representing
10497 a type. Return true when argument is valid. */
10499 static bool
10501 {
10509 }
10511 /* This function validates the types of a function call argument list
10512 against a specified list of tree_codes. If the last specifier is a 0,
10513 that represents an ellipses, otherwise the last specifier must be a
10514 VOID_TYPE.
10516 This is the GIMPLE version of validate_arglist. Eventually we want to
10517 completely convert builtins.c to work from GIMPLEs and the tree based
10518 validate_arglist will then be removed. */
10520 bool
10522 {
10526 const_tree arg;
10532 do
10533 {
10536 {
10538 /* This signifies an ellipses, any further arguments are all ok. */
10542 /* This signifies an endlink, if no arguments remain, return
10543 true, otherwise return false. */
10547 /* If no parameters remain or the parameter's code does not
10548 match the specified code, return false. Otherwise continue
10549 checking any remaining arguments. */
10554 }
10555 }
10558 /* We need gotos here since we can only have one VA_CLOSE in a
10559 function. */
10560 end: ;
10564 }
10566 /* Default target-specific builtin expander that does nothing. */
10568 rtx
10570 rtx target ATTRIBUTE_UNUSED,
10571 rtx subtarget ATTRIBUTE_UNUSED,
10572 machine_mode mode ATTRIBUTE_UNUSED,
10574 {
10576 }
10578 /* Returns true is EXP represents data that would potentially reside
10579 in a readonly section. */
10581 bool
10583 {
10593 /* Make sure we call decl_readonly_section only for trees it
10594 can handle (since it returns true for everything it doesn't
10595 understand). */
10600 else
10602 }
10604 /* Simplify a call to the strpbrk builtin. S1 and S2 are the arguments
10605 to the call, and TYPE is its return type.
10607 Return NULL_TREE if no simplification was possible, otherwise return the
10608 simplified form of the call as a tree.
10610 The simplified form may be a constant or other expression which
10611 computes the same value, but in a more efficient manner (including
10612 calls to other builtin functions).
10614 The call may contain arguments which need to be evaluated, but
10615 which are not useful to determine the result of the call. In
10616 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10617 COMPOUND_EXPR will be an argument which must be evaluated.
10618 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10619 COMPOUND_EXPR in the chain will contain the tree for the simplified
10620 form of the builtin function call. */
10622 static tree
10624 {
10633 tree fn;
10642 {
10644 tree tem;
10649 /* Return an offset into the constant string argument. */
10652 }
10655 /* strpbrk(x, "") == NULL.
10656 Evaluate and ignore s1 in case it had side-effects. */
10666 /* New argument list transforming strpbrk(s1, s2) to
10667 strchr(s1, s2[0]). */
10670 }
10672 /* Simplify a call to the strspn builtin. S1 and S2 are the arguments
10673 to the call.
10675 Return NULL_TREE if no simplification was possible, otherwise return the
10676 simplified form of the call as a tree.
10678 The simplified form may be a constant or other expression which
10679 computes the same value, but in a more efficient manner (including
10680 calls to other builtin functions).
10682 The call may contain arguments which need to be evaluated, but
10683 which are not useful to determine the result of the call. In
10684 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10685 COMPOUND_EXPR will be an argument which must be evaluated.
10686 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10687 COMPOUND_EXPR in the chain will contain the tree for the simplified
10688 form of the builtin function call. */
10690 static tree
10692 {
10703 /* If either argument is "", return NULL_TREE. */
10705 /* Evaluate and ignore both arguments in case either one has
10706 side-effects. */
10710 }
10712 /* Simplify a call to the strcspn builtin. S1 and S2 are the arguments
10713 to the call.
10715 Return NULL_TREE if no simplification was possible, otherwise return the
10716 simplified form of the call as a tree.
10718 The simplified form may be a constant or other expression which
10719 computes the same value, but in a more efficient manner (including
10720 calls to other builtin functions).
10722 The call may contain arguments which need to be evaluated, but
10723 which are not useful to determine the result of the call. In
10724 this case we return a chain of COMPOUND_EXPRs. The LHS of each
10725 COMPOUND_EXPR will be an argument which must be evaluated.
10726 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
10727 COMPOUND_EXPR in the chain will contain the tree for the simplified
10728 form of the builtin function call. */
10730 static tree
10732 {
10741 /* If the first argument is "", return NULL_TREE. */
10744 {
10745 /* Evaluate and ignore argument s2 in case it has
10746 side-effects. */
10749 }
10751 /* If the second argument is "", return __builtin_strlen(s1). */
10754 {
10757 /* If the replacement _DECL isn't initialized, don't do the
10758 transformation. */
10763 }
10765 }
10767 /* Fold the next_arg or va_start call EXP. Returns true if there was an error
10768 produced. False otherwise. This is done so that we don't output the error
10769 or warning twice or three times. */
10771 bool
10773 {
10776 tree arg;
10777 /* There is good chance the current input_location points inside the
10778 definition of the va_start macro (perhaps on the token for
10779 builtin) in a system header, so warnings will not be emitted.
10780 Use the location in real source code. */
10781 location_t current_location =
10783 NULL);
10786 {
10789 }
10792 {
10794 {
10797 }
10799 }
10800 /* We use __builtin_va_start (ap, 0, 0) or __builtin_next_arg (0, 0)
10801 when we checked the arguments and if needed issued a warning. */
10802 else
10803 {
10805 {
10806 /* Evidently an out of date version of <stdarg.h>; can't validate
10807 va_start's second argument, but can still work as intended. */
10809 OPT_Wvarargs,
10812 }
10814 {
10817 }
10819 }
10824 /* We destructively modify the call to be __builtin_va_start (ap, 0)
10825 or __builtin_next_arg (0) the first time we see it, after checking
10826 the arguments and if needed issuing a warning. */
10828 {
10831 /* Strip off all nops for the sake of the comparison. This
10832 is not quite the same as STRIP_NOPS. It does more.
10833 We must also strip off INDIRECT_EXPR for C++ reference
10834 parameters. */
10839 {
10840 /* FIXME: Sometimes with the tree optimizers we can get the
10841 not the last argument even though the user used the last
10842 argument. We just warn and set the arg to be the last
10843 argument so that we will get wrong-code because of
10844 it. */
10846 OPT_Wvarargs,
10848 }
10850 /* Undefined by C99 7.15.1.4p4 (va_start):
10851 "If the parameter parmN is declared with the register storage
10852 class, with a function or array type, or with a type that is
10853 not compatible with the type that results after application of
10854 the default argument promotions, the behavior is undefined."
10855 */
10857 {
10859 OPT_Wvarargs,
10860 "undefined behavior when second parameter of "
10862 }
10864 /* We want to verify the second parameter just once before the tree
10865 optimizers are run and then avoid keeping it in the tree,
10866 as otherwise we could warn even for correct code like:
10867 void foo (int i, ...)
10868 { va_list ap; i++; va_start (ap, i); va_end (ap); } */
10871 else
10873 }
10875 }
10878 /* Expand a call EXP to __builtin_object_size. */
10880 static rtx
10882 {
10883 tree ost;
10888 {
10893 }
10901 {
10906 }
10911 }
10913 /* Expand EXP, a call to the __mem{cpy,pcpy,move,set}_chk builtin.
10914 FCODE is the BUILT_IN_* to use.
10915 Return NULL_RTX if we failed; the caller should emit a normal call,
10916 otherwise try to get the result in TARGET, if convenient (and in
10917 mode MODE if that's convenient). */
10919 static rtx
10922 {
10924 POINTER_TYPE,
10925 fcode == BUILT_IN_MEMSET_CHK
10942 {
10943 /* Avoid transforming the checking call to an ordinary one when
10944 an overflow has been detected or when the call couldn't be
10945 validated because the size is not constant. */
10950 /* If __builtin_mem{cpy,pcpy,move,set}_chk is used, assume
10951 mem{cpy,pcpy,move,set} is available. */
10953 {
10968 }
10977 }
10980 else
10981 {
10984 /* If DEST is not a pointer type, call the normal function. */
10988 /* If SRC and DEST are the same (and not volatile), do nothing. */
10990 {
10991 tree expr;
10994 {
10995 /* Evaluate and ignore LEN in case it has side-effects. */
10998 }
11002 }
11004 /* __memmove_chk special case. */
11006 {
11012 /* If src is categorized for a readonly section we can use
11013 normal __memcpy_chk. */
11015 {
11024 }
11025 }
11027 }
11028 }
11030 /* Emit warning if a buffer overflow is detected at compile time. */
11032 static void
11034 {
11035 /* The source string. */
11037 /* The size of the destination object. */
11039 /* The string that is being concatenated with (as in __strcat_chk)
11040 or null if it isn't. */
11042 /* The maximum length of the source sequence in a bounded operation
11043 (such as __strncat_chk) or null if the operation isn't bounded
11044 (such as __strcat_chk). */
11046 /* The exact size of the access (such as in __strncpy_chk). */
11050 {
11058 /* For __strcat_chk the warning will be emitted only if overflowing
11059 by at least strlen (dest) + 1 bytes. */
11086 }
11089 {
11090 /* Check __strncat_chk. There is no way to determine the length
11091 of the string to which the source string is being appended so
11092 just warn when the length of the source string is not known. */
11095 }
11097 /* The destination argument is the first one for all built-ins above. */
11101 }
11103 /* Emit warning if a buffer overflow is detected at compile time
11104 in __sprintf_chk/__vsprintf_chk calls. */
11106 static void
11108 {
11113 /* Verify the required arguments in the original call. */
11123 /* Check whether the format is a literal string constant. */
11131 /* If the format doesn't contain % args or %%, we know its size. */
11134 /* If the format is "%s" and first ... argument is a string literal,
11135 we know it too. */
11138 {
11139 tree arg;
11150 }
11151 else
11154 /* Add one for the terminating nul. */
11159 }
11161 /* Emit warning if a free is called with address of a variable. */
11163 static void
11165 {
11182 else
11185 }
11187 /* Fold a call to __builtin_object_size with arguments PTR and OST,
11188 if possible. */
11190 static tree
11192 {
11209 /* __builtin_object_size doesn't evaluate side-effects in its arguments;
11210 if there are any side-effects, it returns (size_t) -1 for types 0 and 1
11211 and (size_t) 0 for types 2 and 3. */
11216 {
11220 }
11222 {
11223 /* If object size is not known yet, delay folding until
11224 later. Maybe subsequent passes will help determining
11225 it. */
11229 }
11232 }
11234 /* Builtins with folding operations that operate on "..." arguments
11235 need special handling; we need to store the arguments in a convenient
11236 data structure before attempting any folding. Fortunately there are
11237 only a few builtins that fall into this category. FNDECL is the
11238 function, EXP is the CALL_EXPR for the call. */
11240 static tree
11242 {
11247 {
11254 }
11256 {
11261 }
11263 }
11265 /* Initialize format string characters in the target charset. */
11267 bool
11269 {
11272 {
11295 }
11297 }
11299 /* Helper function for do_mpfr_arg*(). Ensure M is a normal number
11300 and no overflow/underflow occurred. INEXACT is true if M was not
11301 exactly calculated. TYPE is the tree type for the result. This
11302 function assumes that you cleared the MPFR flags and then
11303 calculated M to see if anything subsequently set a flag prior to
11304 entering this function. Return NULL_TREE if any checks fail. */
11306 static tree
11308 {
11309 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
11310 overflow/underflow occurred. If -frounding-math, proceed iff the
11311 result of calling FUNC was exact. */
11314 {
11315 REAL_VALUE_TYPE rr;
11318 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR value,
11319 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
11320 but the mpft_t is not, then we underflowed in the
11321 conversion. */
11324 {
11325 REAL_VALUE_TYPE rmode;
11328 /* Proceed iff the specified mode can hold the value. */
11331 }
11332 }
11334 }
11336 /* Helper function for do_mpc_arg*(). Ensure M is a normal complex
11337 number and no overflow/underflow occurred. INEXACT is true if M
11338 was not exactly calculated. TYPE is the tree type for the result.
11339 This function assumes that you cleared the MPFR flags and then
11340 calculated M to see if anything subsequently set a flag prior to
11341 entering this function. Return NULL_TREE if any checks fail, if
11342 FORCE_CONVERT is true, then bypass the checks. */
11344 static tree
11346 {
11347 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
11348 overflow/underflow occurred. If -frounding-math, proceed iff the
11349 result of calling FUNC was exact. */
11354 {
11359 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR values,
11360 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
11361 but the mpft_t is not, then we underflowed in the
11362 conversion. */
11367 {
11372 /* Proceed iff the specified mode can hold the value. */
11378 }
11379 }
11381 }
11383 /* If arguments ARG0 and ARG1 are REAL_CSTs, call mpfr_remquo() to set
11384 the pointer *(ARG_QUO) and return the result. The type is taken
11385 from the type of ARG0 and is used for setting the precision of the
11386 calculation and results. */
11388 static tree
11390 {
11397 /* To proceed, MPFR must exactly represent the target floating point
11398 format, which only happens when the target base equals two. */
11402 {
11407 {
11411 tree result_rem;
11420 /* Remquo is independent of the rounding mode, so pass
11421 inexact=0 to do_mpfr_ckconv(). */
11425 {
11426 /* MPFR calculates quo in the host's long so it may
11427 return more bits in quo than the target int can hold
11428 if sizeof(host long) > sizeof(target int). This can
11429 happen even for native compilers in LP64 mode. In
11430 these cases, modulo the quo value with the largest
11431 number that the target int can hold while leaving one
11432 bit for the sign. */
11436 /* Dereference the quo pointer argument. */
11438 /* Proceed iff a valid pointer type was passed in. */
11440 {
11441 /* Set the value. */
11442 tree result_quo
11445 integer_quo));
11447 /* Combine the quo assignment with the rem. */
11450 }
11451 }
11452 }
11453 }
11455 }
11457 /* If ARG is a REAL_CST, call mpfr_lgamma() on it and return the
11458 resulting value as a tree with type TYPE. The mpfr precision is
11459 set to the precision of TYPE. We assume that this mpfr function
11460 returns zero if the result could be calculated exactly within the
11461 requested precision. In addition, the integer pointer represented
11462 by ARG_SG will be dereferenced and set to the appropriate signgam
11463 (-1,1) value. */
11465 static tree
11467 {
11472 /* To proceed, MPFR must exactly represent the target floating point
11473 format, which only happens when the target base equals two. Also
11474 verify ARG is a constant and that ARG_SG is an int pointer. */
11479 {
11482 /* In addition to NaN and Inf, the argument cannot be zero or a
11483 negative integer. */
11487 {
11492 mpfr_t m;
11493 tree result_lg;
11502 {
11503 tree result_sg;
11505 /* Dereference the arg_sg pointer argument. */
11507 /* Assign the signgam value into *arg_sg. */
11512 /* Combine the signgam assignment with the lgamma result. */
11515 }
11516 }
11517 }
11520 }
11522 /* If arguments ARG0 and ARG1 are a COMPLEX_CST, call the two-argument
11523 mpc function FUNC on it and return the resulting value as a tree
11524 with type TYPE. The mpfr precision is set to the precision of
11525 TYPE. We assume that function FUNC returns zero if the result
11526 could be calculated exactly within the requested precision. If
11527 DO_NONFINITE is true, then fold expressions containing Inf or NaN
11528 in the arguments and/or results. */
11530 tree
11533 {
11539 /* To proceed, MPFR must exactly represent the target floating point
11540 format, which only happens when the target base equals two. */
11546 {
11555 {
11576 }
11577 }
11580 }
11582 /* A wrapper function for builtin folding that prevents warnings for
11583 "statement without effect" and the like, caused by removing the
11584 call node earlier than the warning is generated. */
11586 tree
11588 {
11594 {
11603 {
11605 }
11606 else
11607 {
11610 {
11611 /* Propagate location information from original call to
11612 expansion of builtin. Otherwise things like
11613 maybe_emit_chk_warning, that operate on the expansion
11614 of a builtin, will use the wrong location information. */
11616 {
11624 }
11626 }
11627 }
11628 }
11630 }
11632 /* Look up the function in builtin_decl that corresponds to DECL
11633 and set ASMSPEC as its user assembler name. DECL must be a
11634 function decl that declares a builtin. */
11636 void
11638 {
11647 {
11651 }
11652 }
11654 /* Return true if DECL is a builtin that expands to a constant or similarly
11655 simple code. */
11656 bool
11658 {
11661 {
11662 /* Builtins that expand to constants. */
11667 /* Simple register moves or loads from stack. */
11678 /* Exception state returns or moves registers around. */
11686 }
11689 }
11691 /* Return true if DECL is a builtin that is not expensive, i.e., they are
11692 most probably expanded inline into reasonably simple code. This is a
11693 superset of is_simple_builtin. */
11694 bool
11696 {
11703 {
11705 CASE_BUILT_IN_ALLOCA:
11771 }
11774 }
11776 /* Return true if T is a constant and the value cast to a target char
11777 can be represented by a host char.
11778 Store the casted char constant in *P if so. */
11780 bool
11782 {
11788 }
11790 /* Return true if the builtin DECL is implemented in a standard library.
11791 Otherwise returns false which doesn't guarantee it is not (thus the list of
11792 handled builtins below may be incomplete). */
11794 bool
11796 {
11799 {
11873 }
11875 }