| blob | d3498bb16c47995e68a0d6406ecf6f3d227ce74e |
1 /* Expand builtin functions.
2 Copyright (C) 1988-2017 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* 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. */
75 #if SWITCHABLE_TARGET
77 #endif
79 /* Define the names of the builtin function types and codes. */
83 #define DEF_BUILTIN(X, N, C, T, LT, B, F, NA, AT, IM, COND) #X,
85 {
87 };
89 /* Setup an array of builtin_info_type, make sure each element decl is
90 initialized to NULL_TREE. */
93 /* Non-zero if __builtin_constant_p should be folded right away. */
195 /* Return true if NAME starts with __builtin_ or __sync_. */
197 static bool
199 {
211 }
214 /* Return true if DECL is a function symbol representing a built-in. */
216 bool
218 {
220 }
222 /* Return true if NODE should be considered for inline expansion regardless
223 of the optimization level. This means whenever a function is invoked with
224 its "internal" name, which normally contains the prefix "__builtin". */
226 bool
228 {
229 /* Note that we must use DECL_NAME, not DECL_ASSEMBLER_NAME_SET_P since
230 we want the name used to call the function, not the name it
231 will have. */
234 }
236 /* Compute values M and N such that M divides (address of EXP - N) and such
237 that N < M. If these numbers can be determined, store M in alignp and N in
238 *BITPOSP and return true. Otherwise return false and store BITS_PER_UNIT to
239 *alignp and any bit-offset to *bitposp.
241 Note that the address (and thus the alignment) computed here is based
242 on the address to which a symbol resolves, whereas DECL_ALIGN is based
243 on the address at which an object is actually located. These two
244 addresses are not always the same. For example, on ARM targets,
245 the address &foo of a Thumb function foo() has the lowest bit set,
246 whereas foo() itself starts on an even address.
248 If ADDR_P is true we are taking the address of the memory reference EXP
249 and thus cannot rely on the access taking place. */
251 static bool
254 {
256 tree offset;
257 machine_mode mode;
262 /* Get the innermost object and the constant (bitpos) and possibly
263 variable (offset) offset of the access. */
267 /* Extract alignment information from the innermost object and
268 possibly adjust bitpos and offset. */
270 {
271 /* Function addresses can encode extra information besides their
272 alignment. However, if TARGET_PTRMEMFUNC_VBIT_LOCATION
273 allows the low bit to be used as a virtual bit, we know
274 that the address itself must be at least 2-byte aligned. */
277 }
279 ;
281 {
282 /* The alignment of a CONST_DECL is determined by its initializer. */
289 }
291 {
294 }
298 {
304 /* If the address is explicitely aligned, handle that. */
307 {
312 }
314 known_alignment
318 /* Re-apply explicit alignment to the bitpos. */
321 /* The alignment of the pointer operand in a TARGET_MEM_REF
322 has to take the variable offset parts into account. */
324 {
326 {
331 }
335 }
337 /* When EXP is an actual memory reference then we can use
338 TYPE_ALIGN of a pointer indirection to derive alignment.
339 Do so only if get_pointer_alignment_1 did not reveal absolute
340 alignment knowledge and if using that alignment would
341 improve the situation. */
347 else
348 {
349 /* Else adjust bitpos accordingly. */
354 }
355 }
357 {
358 /* STRING_CST are the only constant objects we allow to be not
359 wrapped inside a CONST_DECL. */
365 }
367 /* If there is a non-constant offset part extract the maximum
368 alignment that can prevail. */
370 {
373 {
377 }
378 }
383 }
385 /* For a memory reference expression EXP compute values M and N such that M
386 divides (&EXP - N) and such that N < M. If these numbers can be determined,
387 store M in alignp and N in *BITPOSP and return true. Otherwise return false
388 and store BITS_PER_UNIT to *alignp and any bit-offset to *bitposp. */
390 bool
393 {
395 }
397 /* Return the alignment in bits of EXP, an object. */
399 unsigned int
401 {
407 /* align and bitpos now specify known low bits of the pointer.
408 ptr & (align - 1) == bitpos. */
413 }
415 /* For a pointer valued expression EXP compute values M and N such that M
416 divides (EXP - N) and such that N < M. If these numbers can be determined,
417 store M in alignp and N in *BITPOSP and return true. Return false if
418 the results are just a conservative approximation.
420 If EXP is not a pointer, false is returned too. */
422 bool
425 {
432 {
439 else
440 {
443 {
447 }
448 }
452 }
455 {
460 {
463 /* Make sure to return a sensible alignment when the multiplication
464 by BITS_PER_UNIT overflowed. */
467 /* We cannot really tell whether this result is an approximation. */
469 }
470 else
471 {
475 }
476 }
478 {
483 }
488 }
490 /* Return the alignment in bits of EXP, a pointer valued expression.
491 The alignment returned is, by default, the alignment of the thing that
492 EXP points to. If it is not a POINTER_TYPE, 0 is returned.
494 Otherwise, look at the expression to see if we can do better, i.e., if the
495 expression is actually pointing at an object whose alignment is tighter. */
497 unsigned int
499 {
505 /* align and bitpos now specify known low bits of the pointer.
506 ptr & (align - 1) == bitpos. */
512 }
514 /* Return the number of non-zero elements in the sequence
515 [ PTR, PTR + MAXELTS ) where each element's size is ELTSIZE bytes.
516 ELTSIZE must be a power of 2 less than 8. Used by c_strlen. */
518 static unsigned
520 {
526 {
527 /* Optimize the common case of plain char. */
529 {
533 }
534 }
535 else
536 {
538 {
542 }
543 }
545 }
547 /* Compute the length of a null-terminated character string or wide
548 character string handling character sizes of 1, 2, and 4 bytes.
549 TREE_STRING_LENGTH is not the right way because it evaluates to
550 the size of the character array in bytes (as opposed to characters)
551 and because it can contain a zero byte in the middle.
553 ONLY_VALUE should be nonzero if the result is not going to be emitted
554 into the instruction stream and zero if it is going to be expanded.
555 E.g. with i++ ? "foo" : "bar", if ONLY_VALUE is nonzero, constant 3
556 is returned, otherwise NULL, since
557 len = c_strlen (src, 1); if (len) expand_expr (len, ...); would not
558 evaluate the side-effects.
560 If ONLY_VALUE is two then we do not emit warnings about out-of-bound
561 accesses. Note that this implies the result is not going to be emitted
562 into the instruction stream.
564 The value returned is of type `ssizetype'.
566 Unfortunately, string_constant can't access the values of const char
567 arrays with initializers, so neither can we do so here. */
569 tree
571 {
575 {
582 }
590 /* Offset from the beginning of the string in bytes. */
591 tree byteoff;
596 /* Determine the size of the string element. */
597 unsigned eltsize
600 /* Set MAXELTS to sizeof (SRC) / sizeof (*SRC) - 1, the maximum possible
601 length of SRC. */
604 /* PTR can point to the byte representation of any string type, including
605 char* and wchar_t*. */
609 {
610 /* If the string has an internal zero byte (e.g., "foo\0bar"), we can't
611 compute the offset to the following null if we don't know where to
612 start searching for it. */
614 {
615 /* Return when an embedded null character is found. */
617 }
619 /* We don't know the starting offset, but we do know that the string
620 has no internal zero bytes. We can assume that the offset falls
621 within the bounds of the string; otherwise, the programmer deserves
622 what he gets. Subtract the offset from the length of the string,
623 and return that. This would perhaps not be valid if we were dealing
624 with named arrays in addition to literal string constants. */
627 }
629 /* Offset from the beginning of the string in elements. */
630 HOST_WIDE_INT eltoff;
632 /* We have a known offset into the string. Start searching there for
633 a null character if we can represent it as a single HOST_WIDE_INT. */
638 else
641 /* If the offset is known to be out of bounds, warn, and call strlen at
642 runtime. */
644 {
645 /* Suppress multiple warnings for propagated constant strings. */
648 {
650 eltoff);
652 }
654 }
656 /* Use strlen to search for the first zero byte. Since any strings
657 constructed with build_string will have nulls appended, we win even
658 if we get handed something like (char[4])"abcd".
660 Since ELTOFF is our starting index into the string, no further
661 calculation is needed. */
666 }
668 /* Return a constant integer corresponding to target reading
669 GET_MODE_BITSIZE (MODE) bits from string constant STR. */
671 static rtx
673 {
674 HOST_WIDE_INT ch;
688 {
700 }
704 }
706 /* Cast a target constant CST to target CHAR and if that value fits into
707 host char type, return zero and put that value into variable pointed to by
708 P. */
710 static int
712 {
719 /* Do not care if it fits or not right here. */
734 }
736 /* Similar to save_expr, but assumes that arbitrary code is not executed
737 in between the multiple evaluations. In particular, we assume that a
738 non-addressable local variable will not be modified. */
740 static tree
742 {
750 }
752 /* Given TEM, a pointer to a stack frame, follow the dynamic chain COUNT
753 times to get the address of either a higher stack frame, or a return
754 address located within it (depending on FNDECL_CODE). */
756 static rtx
758 {
762 {
763 /* For a zero count with __builtin_return_address, we don't care what
764 frame address we return, because target-specific definitions will
765 override us. Therefore frame pointer elimination is OK, and using
766 the soft frame pointer is OK.
768 For a nonzero count, or a zero count with __builtin_frame_address,
769 we require a stable offset from the current frame pointer to the
770 previous one, so we must use the hard frame pointer, and
771 we must disable frame pointer elimination. */
774 else
775 {
778 /* Tell reload not to eliminate the frame pointer. */
780 }
781 }
786 /* On the SPARC, the return address is not in the frame, it is in a
787 register. There is no way to access it off of the current frame
788 pointer, but it can be accessed off the previous frame pointer by
789 reading the value from the register window save area. */
791 count--;
793 /* Scan back COUNT frames to the specified frame. */
795 {
796 /* Assume the dynamic chain pointer is in the word that the
797 frame address points to, unless otherwise specified. */
802 }
804 /* For __builtin_frame_address, return what we've got. But, on
805 the SPARC for example, we may have to add a bias. */
809 /* For __builtin_return_address, get the return address from that frame. */
810 #ifdef RETURN_ADDR_RTX
812 #else
816 #endif
818 }
820 /* Alias set used for setjmp buffer. */
823 /* Construct the leading half of a __builtin_setjmp call. Control will
824 return to RECEIVER_LABEL. This is also called directly by the SJLJ
825 exception handling code. */
827 void
829 {
831 rtx stack_save;
832 rtx mem;
841 /* We store the frame pointer and the address of receiver_label in
842 the buffer and use the rest of it for the stack save area, which
843 is machine-dependent. */
862 /* If there is further processing to do, do it. */
866 /* We have a nonlocal label. */
868 }
870 /* Construct the trailing part of a __builtin_setjmp call. This is
871 also called directly by the SJLJ exception handling code.
872 If RECEIVER_LABEL is NULL, instead contruct a nonlocal goto handler. */
874 void
876 {
877 rtx chain;
879 /* Mark the FP as used when we get here, so we have to make sure it's
880 marked as used by this function. */
883 /* Mark the static chain as clobbered here so life information
884 doesn't get messed up for it. */
889 /* Now put in the code to restore the frame pointer, and argument
890 pointer, if needed. */
892 {
893 /* First adjust our frame pointer to its actual value. It was
894 previously set to the start of the virtual area corresponding to
895 the stacked variables when we branched here and now needs to be
896 adjusted to the actual hardware fp value.
898 Assignments to virtual registers are converted by
899 instantiate_virtual_regs into the corresponding assignment
900 to the underlying register (fp in this case) that makes
901 the original assignment true.
902 So the following insn will actually be decrementing fp by
903 STARTING_FRAME_OFFSET. */
906 /* Restoring the frame pointer also modifies the hard frame pointer.
907 Mark it used (so that the previous assignment remains live once
908 the frame pointer is eliminated) and clobbered (to represent the
909 implicit update from the assignment). */
912 }
915 {
916 /* If the argument pointer can be eliminated in favor of the
917 frame pointer, we don't need to restore it. We assume here
918 that if such an elimination is present, it can always be used.
919 This is the case on all known machines; if we don't make this
920 assumption, we do unnecessary saving on many machines. */
930 {
931 /* Now restore our arg pointer from the address at which it
932 was saved in our stack frame. */
935 }
936 }
942 else
945 /* We must not allow the code we just generated to be reordered by
946 scheduling. Specifically, the update of the frame pointer must
947 happen immediately, not later. */
949 }
951 /* __builtin_longjmp is passed a pointer to an array of five words (not
952 all will be used on all machines). It operates similarly to the C
953 library function of the same name, but is more efficient. Much of
954 the code below is copied from the handling of non-local gotos. */
956 static void
958 {
963 /* DRAP is needed for stack realign if longjmp is expanded to current
964 function */
975 /* We require that the user must pass a second argument of 1, because
976 that is what builtin_setjmp will return. */
982 else
983 {
994 /* Pick up FP, label, and SP from the block and jump. This code is
995 from expand_goto in stmt.c; see there for detailed comments. */
997 /* We have to pass a value to the nonlocal_goto pattern that will
998 get copied into the static_chain pointer, but it does not matter
999 what that value is, because builtin_setjmp does not use it. */
1001 else
1002 {
1014 }
1015 }
1017 /* Search backwards and mark the jump insn as a non-local goto.
1018 Note that this precludes the use of __builtin_longjmp to a
1019 __builtin_setjmp target in the same function. However, we've
1020 already cautioned the user that these functions are for
1021 internal exception handling use only. */
1023 {
1027 {
1030 }
1033 }
1034 }
1038 {
1040 }
1042 /* This function validates the types of a function call argument list
1043 against a specified list of tree_codes. If the last specifier is a 0,
1044 that represents an ellipsis, otherwise the last specifier must be a
1045 VOID_TYPE. */
1047 static bool
1049 {
1053 const_call_expr_arg_iterator iter;
1054 const_tree arg;
1059 /* Get a bitmap of pointer argument numbers declared attribute nonnull. */
1064 {
1068 {
1070 /* This signifies an ellipses, any further arguments are all ok. */
1074 /* This signifies an endlink, if no arguments remain, return
1075 true, otherwise return false. */
1079 /* The actual argument must be nonnull when either the whole
1080 called function has been declared nonnull, or when the formal
1081 argument corresponding to the actual argument has been. */
1084 {
1089 }
1090 /* FALLTHRU */
1092 /* If no parameters remain or the parameter's code does not
1093 match the specified code, return false. Otherwise continue
1094 checking any remaining arguments. */
1099 }
1100 }
1102 /* We need gotos here since we can only have one VA_CLOSE in a
1103 function. */
1104 end: ;
1110 }
1112 /* Expand a call to __builtin_nonlocal_goto. We're passed the target label
1113 and the address of the save area. */
1115 static rtx
1117 {
1132 /* Copy the address of the save location to a register just in case it was
1133 based on the frame pointer. */
1142 /* ??? We no longer need to pass the static chain value, afaik. */
1145 else
1146 {
1152 /* Restore frame pointer for containing function. */
1156 /* USE of hard_frame_pointer_rtx added for consistency;
1157 not clear if really needed. */
1161 /* If the architecture is using a GP register, we must
1162 conservatively assume that the target function makes use of it.
1163 The prologue of functions with nonlocal gotos must therefore
1164 initialize the GP register to the appropriate value, and we
1165 must then make sure that this value is live at the point
1166 of the jump. (Note that this doesn't necessarily apply
1167 to targets with a nonlocal_goto pattern; they are free
1168 to implement it in their own way. Note also that this is
1169 a no-op if the GP register is a global invariant.) */
1175 }
1177 /* Search backwards to the jump insn and mark it as a
1178 non-local goto. */
1180 {
1182 {
1185 }
1188 }
1191 }
1193 /* __builtin_update_setjmp_buf is passed a pointer to an array of five words
1194 (not all will be used on all machines) that was passed to __builtin_setjmp.
1195 It updates the stack pointer in that block to the current value. This is
1196 also called directly by the SJLJ exception handling code. */
1198 void
1200 {
1203 rtx stack_save
1205 memory_address
1211 }
1213 /* Expand a call to __builtin_prefetch. For a target that does not support
1214 data prefetch, evaluate the memory address argument in case it has side
1215 effects. */
1217 static void
1219 {
1229 /* Arguments 1 and 2 are optional; argument 1 (read/write) defaults to
1230 zero (read) and argument 2 (locality) defaults to 3 (high degree of
1231 locality). */
1235 else
1239 else
1242 /* Argument 0 is an address. */
1245 /* Argument 1 (read/write flag) must be a compile-time constant int. */
1247 {
1250 }
1252 /* Argument 1 must be either zero or one. */
1254 {
1258 }
1260 /* Argument 2 (locality) must be a compile-time constant int. */
1262 {
1265 }
1267 /* Argument 2 must be 0, 1, 2, or 3. */
1269 {
1272 }
1275 {
1283 }
1285 /* Don't do anything with direct references to volatile memory, but
1286 generate code to handle other side effects. */
1289 }
1291 /* Get a MEM rtx for expression EXP which is the address of an operand
1292 to be used in a string instruction (cmpstrsi, movmemsi, ..). LEN is
1293 the maximum length of the block of memory that might be accessed or
1294 NULL if unknown. */
1296 static rtx
1298 {
1302 /* When EXP is not resolved SAVE_EXPR, MEM_ATTRS can be still derived
1303 from its expression, for expr->a.b only <variable>.a.b is recorded. */
1310 /* Get an expression we can use to find the attributes to assign to MEM.
1311 First remove any nops. */
1316 /* Build a MEM_REF representing the whole accessed area as a byte blob,
1317 (as builtin stringops may alias with anything). */
1324 /* If the MEM_REF has no acceptable address, try to get the base object
1325 from the original address we got, and build an all-aliasing
1326 unknown-sized access to that one. */
1332 {
1337 size_zero_node,
1338 NULL)),
1341 }
1344 }
1345 \f
1346 /* Built-in functions to perform an untyped call and return. */
1348 #define apply_args_mode \
1349 (this_target_builtins->x_apply_args_mode)
1350 #define apply_result_mode \
1351 (this_target_builtins->x_apply_result_mode)
1353 /* Return the size required for the block returned by __builtin_apply_args,
1354 and initialize apply_args_mode. */
1356 static int
1358 {
1362 machine_mode mode;
1364 /* The values computed by this function never change. */
1366 {
1367 /* The first value is the incoming arg-pointer. */
1370 /* The second value is the structure value address unless this is
1371 passed as an "invisible" first argument. */
1377 {
1387 }
1388 else
1389 {
1391 }
1392 }
1394 }
1396 /* Return the size required for the block returned by __builtin_apply,
1397 and initialize apply_result_mode. */
1399 static int
1401 {
1404 machine_mode mode;
1406 /* The values computed by this function never change. */
1408 {
1413 {
1423 }
1424 else
1427 /* Allow targets that use untyped_call and untyped_return to override
1428 the size so that machine-specific information can be stored here. */
1429 #ifdef APPLY_RESULT_SIZE
1431 #endif
1432 }
1434 }
1436 /* Create a vector describing the result block RESULT. If SAVEP is true,
1437 the result block is used to save the values; otherwise it is used to
1438 restore the values. */
1440 static rtx
1442 {
1444 machine_mode mode;
1451 {
1461 }
1463 }
1465 /* Save the state required to perform an untyped call with the same
1466 arguments as were passed to the current function. */
1468 static rtx
1470 {
1473 machine_mode mode;
1474 rtx struct_incoming_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 1);
1476 /* Create a block where the arg-pointer, structure value address,
1477 and argument registers can be saved. */
1480 /* Walk past the arg-pointer and structure value address. */
1485 /* Save each register used in calling a function to the block. */
1488 {
1497 }
1499 /* Save the arg pointer to the block. */
1501 /* We need the pointer as the caller actually passed them to us, not
1502 as we might have pretended they were passed. Make sure it's a valid
1503 operand, as emit_move_insn isn't expected to handle a PLUS. */
1505 tem
1508 NULL_RTX);
1513 /* Save the structure value address unless this is passed as an
1514 "invisible" first argument. */
1516 {
1520 }
1522 /* Return the address of the block. */
1524 }
1526 /* __builtin_apply_args returns block of memory allocated on
1527 the stack into which is stored the arg pointer, structure
1528 value address, static chain, and all the registers that might
1529 possibly be used in performing a function call. The code is
1530 moved to the start of the function so the incoming values are
1531 saved. */
1533 static rtx
1535 {
1536 /* Don't do __builtin_apply_args more than once in a function.
1537 Save the result of the first call and reuse it. */
1540 {
1541 /* When this function is called, it means that registers must be
1542 saved on entry to this function. So we migrate the
1543 call to the first insn of this function. */
1544 rtx temp;
1553 /* Put the insns after the NOTE that starts the function.
1554 If this is inside a start_sequence, make the outer-level insn
1555 chain current, so the code is placed at the start of the
1556 function. If internal_arg_pointer is a non-virtual pseudo,
1557 it needs to be placed after the function that initializes
1558 that pseudo. */
1563 else
1567 }
1568 }
1570 /* Perform an untyped call and save the state required to perform an
1571 untyped return of whatever value was returned by the given function. */
1573 static rtx
1575 {
1577 machine_mode mode;
1586 /* Create a block where the return registers can be saved. */
1589 /* Fetch the arg pointer from the ARGUMENTS block. */
1596 /* Push a new argument block and copy the arguments. Do not allow
1597 the (potential) memcpy call below to interfere with our stack
1598 manipulations. */
1600 NO_DEFER_POP;
1602 /* Save the stack with nonlocal if available. */
1605 else
1608 /* Allocate a block of memory onto the stack and copy the memory
1609 arguments to the outgoing arguments address. We can pass TRUE
1610 as the 4th argument because we just saved the stack pointer
1611 and will restore it right after the call. */
1614 /* Set DRAP flag to true, even though allocate_dynamic_stack_space
1615 may have already set current_function_calls_alloca to true.
1616 current_function_calls_alloca won't be set if argsize is zero,
1617 so we have to guarantee need_drap is true here. */
1623 {
1626 else
1628 }
1635 /* Refer to the argument block. */
1640 /* Walk past the arg-pointer and structure value address. */
1645 /* Restore each of the registers previously saved. Make USE insns
1646 for each of these registers for use in making the call. */
1649 {
1657 }
1659 /* Restore the structure value address unless this is passed as an
1660 "invisible" first argument. */
1663 {
1670 }
1672 /* All arguments and registers used for the call are set up by now! */
1675 /* Ensure address is valid. SYMBOL_REF is already valid, so no need,
1676 and we don't want to load it into a register as an optimization,
1677 because prepare_call_address already did it if it should be done. */
1681 /* Generate the actual call instruction and save the return value. */
1683 {
1687 }
1689 {
1692 /* Locate the unique return register. It is not possible to
1693 express a call that sets more than one return register using
1694 call_value; use untyped_call for that. In fact, untyped_call
1695 only needs to save the return registers in the given block. */
1698 {
1702 }
1709 }
1710 else
1713 /* Find the CALL insn we just emitted, and attach the register usage
1714 information. */
1718 /* Restore the stack. */
1721 else
1725 OK_DEFER_POP;
1727 /* Return the address of the result block. */
1730 }
1732 /* Perform an untyped return. */
1734 static void
1736 {
1738 machine_mode mode;
1739 rtx reg;
1748 {
1753 }
1755 /* Restore the return value and note that each value is used. */
1759 {
1771 }
1773 /* Put the USE insns before the return. */
1776 /* Return whatever values was restored by jumping directly to the end
1777 of the function. */
1779 }
1781 /* Used by expand_builtin_classify_type and fold_builtin_classify_type. */
1783 static enum type_class
1785 {
1787 {
1806 }
1807 }
1809 /* Expand a call EXP to __builtin_classify_type. */
1811 static rtx
1813 {
1817 }
1819 /* This helper macro, meant to be used in mathfn_built_in below,
1820 determines which among a set of three builtin math functions is
1821 appropriate for a given type mode. The `F' and `L' cases are
1822 automatically generated from the `double' case. */
1823 #define CASE_MATHFN(MATHFN) \
1824 CASE_CFN_##MATHFN: \
1825 fcode = BUILT_IN_##MATHFN; fcodef = BUILT_IN_##MATHFN##F ; \
1826 fcodel = BUILT_IN_##MATHFN##L ; break;
1827 /* Similar to above, but appends _R after any F/L suffix. */
1828 #define CASE_MATHFN_REENT(MATHFN) \
1829 case CFN_BUILT_IN_##MATHFN##_R: \
1830 case CFN_BUILT_IN_##MATHFN##F_R: \
1831 case CFN_BUILT_IN_##MATHFN##L_R: \
1832 fcode = BUILT_IN_##MATHFN##_R; fcodef = BUILT_IN_##MATHFN##F_R ; \
1833 fcodel = BUILT_IN_##MATHFN##L_R ; break;
1835 /* Return a function equivalent to FN but operating on floating-point
1836 values of type TYPE, or END_BUILTINS if no such function exists.
1837 This is purely an operation on function codes; it does not guarantee
1838 that the target actually has an implementation of the function. */
1840 static built_in_function
1842 {
1846 {
1937 }
1945 else
1947 }
1949 /* Return mathematic function equivalent to FN but operating directly on TYPE,
1950 if available. If IMPLICIT_P is true use the implicit builtin declaration,
1951 otherwise use the explicit declaration. If we can't do the conversion,
1952 return null. */
1954 static tree
1956 {
1965 }
1967 /* Like mathfn_built_in_1, but always use the implicit array. */
1969 tree
1971 {
1973 }
1975 /* Like mathfn_built_in_1, but take a built_in_function and
1976 always use the implicit array. */
1978 tree
1980 {
1982 }
1984 /* If BUILT_IN_NORMAL function FNDECL has an associated internal function,
1985 return its code, otherwise return IFN_LAST. Note that this function
1986 only tests whether the function is defined in internals.def, not whether
1987 it is actually available on the target. */
1989 internal_fn
1991 {
1995 {
1996 #define DEF_INTERNAL_FLT_FN(NAME, FLAGS, OPTAB, TYPE) \
1997 CASE_FLT_FN (BUILT_IN_##NAME): return IFN_##NAME;
1998 #define DEF_INTERNAL_INT_FN(NAME, FLAGS, OPTAB, TYPE) \
1999 CASE_INT_FN (BUILT_IN_##NAME): return IFN_##NAME;
2016 }
2017 }
2019 /* If CALL is a call to a BUILT_IN_NORMAL function that could be replaced
2020 on the current target by a call to an internal function, return the
2021 code of that internal function, otherwise return IFN_LAST. The caller
2022 is responsible for ensuring that any side-effects of the built-in
2023 call are dealt with correctly. E.g. if CALL sets errno, the caller
2024 must decide that the errno result isn't needed or make it available
2025 in some other way. */
2027 internal_fn
2029 {
2031 {
2034 {
2039 }
2040 }
2042 }
2044 /* Expand a call to the builtin trinary math functions (fma).
2045 Return NULL_RTX if a normal call should be emitted rather than expanding the
2046 function in-line. EXP is the expression that is a call to the builtin
2047 function; if convenient, the result should be placed in TARGET.
2048 SUBTARGET may be used as the target for computing one of EXP's
2049 operands. */
2051 static rtx
2053 {
2054 optab builtin_optab;
2059 machine_mode mode;
2069 {
2074 }
2076 /* Make a suitable register to place result in. */
2079 /* Before working hard, check whether the instruction is available. */
2085 /* Always stabilize the argument list. */
2096 /* Compute into RESULT.
2097 Set RESULT to wherever the result comes back. */
2101 /* If we were unable to expand via the builtin, stop the sequence
2102 (without outputting the insns) and call to the library function
2103 with the stabilized argument list. */
2105 {
2108 }
2110 /* Output the entire sequence. */
2116 }
2118 /* Expand a call to the builtin sin and cos math functions.
2119 Return NULL_RTX if a normal call should be emitted rather than expanding the
2120 function in-line. EXP is the expression that is a call to the builtin
2121 function; if convenient, the result should be placed in TARGET.
2122 SUBTARGET may be used as the target for computing one of EXP's
2123 operands. */
2125 static rtx
2127 {
2128 optab builtin_optab;
2129 rtx op0;
2132 machine_mode mode;
2133 tree arg;
2141 {
2147 }
2149 /* Make a suitable register to place result in. */
2152 /* Check if sincos insn is available, otherwise fallback
2153 to sin or cos insn. */
2156 {
2163 }
2165 /* Before working hard, check whether the instruction is available. */
2167 {
2170 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2171 need to expand the argument again. This way, we will not perform
2172 side-effects more the once. */
2179 /* Compute into RESULT.
2180 Set RESULT to wherever the result comes back. */
2182 {
2186 {
2195 }
2197 }
2198 else
2202 {
2203 /* Output the entire sequence. */
2208 }
2210 /* If we were unable to expand via the builtin, stop the sequence
2211 (without outputting the insns) and call to the library function
2212 with the stabilized argument list. */
2214 }
2217 }
2219 /* Given an interclass math builtin decl FNDECL and it's argument ARG
2220 return an RTL instruction code that implements the functionality.
2221 If that isn't possible or available return CODE_FOR_nothing. */
2223 static enum insn_code
2225 {
2228 machine_mode mode;
2231 {
2245 /* These builtins have no optabs (yet). */
2249 }
2251 /* There's no easy way to detect the case we need to set EDOM. */
2255 /* Optab mode depends on the mode of the input argument. */
2261 }
2263 /* Expand a call to one of the builtin math functions that operate on
2264 floating point argument and output an integer result (ilogb, isinf,
2265 isnan, etc).
2266 Return 0 if a normal call should be emitted rather than expanding the
2267 function in-line. EXP is the expression that is a call to the builtin
2268 function; if convenient, the result should be placed in TARGET. */
2270 static rtx
2272 {
2274 rtx op0;
2276 machine_mode mode;
2277 tree arg;
2287 {
2292 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2293 need to expand the argument again. This way, we will not perform
2294 side-effects more the once. */
2309 }
2312 }
2314 /* Expand a call to the builtin sincos math function.
2315 Return NULL_RTX if a normal call should be emitted rather than expanding the
2316 function in-line. EXP is the expression that is a call to the builtin
2317 function. */
2319 static rtx
2321 {
2323 machine_mode mode;
2337 /* Make a suitable register to place result in. */
2340 /* Check if sincos insn is available, otherwise emit the call. */
2355 /* Compute into target1 and target2.
2356 Set TARGET to wherever the result comes back. */
2360 /* Move target1 and target2 to the memory locations indicated
2361 by op1 and op2. */
2366 }
2368 /* Expand a call to the internal cexpi builtin to the sincos math function.
2369 EXP is the expression that is a call to the builtin function; if convenient,
2370 the result should be placed in TARGET. */
2372 static rtx
2374 {
2377 machine_mode mode;
2388 /* Try expanding via a sincos optab, fall back to emitting a libcall
2389 to sincos or cexp. We are sure we have sincos or cexp because cexpi
2390 is only generated from sincos, cexp or if we have either of them. */
2392 {
2398 /* Compute into op1 and op2. */
2400 }
2402 {
2413 else
2423 /* Make sure not to fold the sincos call again. */
2427 }
2428 else
2429 {
2439 else
2442 /* If we don't have a decl for cexp create one. This is the
2443 friendliest fallback if the user calls __builtin_cexpi
2444 without full target C99 function support. */
2446 {
2447 tree fntype;
2459 }
2464 /* Make sure not to fold the cexp call again. */
2468 }
2470 /* Now build the proper return type. */
2475 }
2477 /* Conveniently construct a function call expression. FNDECL names the
2478 function to be called, N is the number of arguments, and the "..."
2479 parameters are the argument expressions. Unlike build_call_exr
2480 this doesn't fold the call, hence it will always return a CALL_EXPR. */
2482 static tree
2484 {
2494 }
2496 /* Expand a call to one of the builtin rounding functions gcc defines
2497 as an extension (lfloor and lceil). As these are gcc extensions we
2498 do not need to worry about setting errno to EDOM.
2499 If expanding via optab fails, lower expression to (int)(floor(x)).
2500 EXP is the expression that is a call to the builtin function;
2501 if convenient, the result should be placed in TARGET. */
2503 static rtx
2505 {
2506 convert_optab builtin_optab;
2511 tree fallback_fndecl;
2512 machine_mode mode;
2513 tree arg;
2521 {
2538 }
2540 /* Make a suitable register to place result in. */
2545 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2546 need to expand the argument again. This way, we will not perform
2547 side-effects more the once. */
2554 /* Compute into TARGET. */
2556 {
2557 /* Output the entire sequence. */
2562 }
2564 /* If we were unable to expand via the builtin, stop the sequence
2565 (without outputting the insns). */
2568 /* Fall back to floating point rounding optab. */
2571 /* For non-C99 targets we may end up without a fallback fndecl here
2572 if the user called __builtin_lfloor directly. In this case emit
2573 a call to the floor/ceil variants nevertheless. This should result
2574 in the best user experience for not full C99 targets. */
2576 {
2577 tree fntype;
2581 {
2614 }
2619 }
2626 /* Truncate the result of floating point optab to integer
2627 via expand_fix (). */
2632 }
2634 /* Expand a call to one of the builtin math functions doing integer
2635 conversion (lrint).
2636 Return 0 if a normal call should be emitted rather than expanding the
2637 function in-line. EXP is the expression that is a call to the builtin
2638 function; if convenient, the result should be placed in TARGET. */
2640 static rtx
2642 {
2643 convert_optab builtin_optab;
2644 rtx op0;
2647 tree arg;
2648 machine_mode mode;
2657 {
2676 }
2678 /* There's no easy way to detect the case we need to set EDOM. */
2682 /* Make a suitable register to place result in. */
2685 /* There's no easy way to detect the case we need to set EDOM. */
2687 {
2690 /* Wrap the computation of the argument in a SAVE_EXPR, as we may
2691 need to expand the argument again. This way, we will not perform
2692 side-effects more the once. */
2700 {
2701 /* Output the entire sequence. */
2706 }
2708 /* If we were unable to expand via the builtin, stop the sequence
2709 (without outputting the insns) and call to the library function
2710 with the stabilized argument list. */
2712 }
2715 {
2716 /* Fall back to rounding to long int. Use implicit_p 0 - for non-C99
2717 targets, (int) round (x) should never be transformed into
2718 BUILT_IN_IROUND and if __builtin_iround is called directly, emit
2719 a call to lround in the hope that the target provides at least some
2720 C99 functions. This should result in the best user experience for
2721 not full C99 targets. */
2722 tree fallback_fndecl = mathfn_built_in_1
2731 }
2734 }
2736 /* Expand a call to the powi built-in mathematical function. Return NULL_RTX if
2737 a normal call should be emitted rather than expanding the function
2738 in-line. EXP is the expression that is a call to the builtin
2739 function; if convenient, the result should be placed in TARGET. */
2741 static rtx
2743 {
2746 machine_mode mode;
2747 machine_mode mode2;
2756 /* Emit a libcall to libgcc. */
2758 /* Mode of the 2nd argument must match that of an int. */
2776 }
2778 /* Expand expression EXP which is a call to the strlen builtin. Return
2779 NULL_RTX if we failed the caller should emit a normal call, otherwise
2780 try to get the result in TARGET, if convenient. */
2782 static rtx
2784 machine_mode target_mode)
2785 {
2788 else
2789 {
2791 rtx pat;
2792 tree len;
2794 rtx src_reg;
2796 machine_mode insn_mode;
2800 /* If the length can be computed at compile-time, return it. */
2805 /* If the length can be computed at compile-time and is constant
2806 integer, but there are side-effects in src, evaluate
2807 src for side-effects, then return len.
2808 E.g. x = strlen (i++ ? "xfoo" + 1 : "bar");
2809 can be optimized into: i++; x = 3; */
2812 {
2815 }
2819 /* If SRC is not a pointer type, don't do this operation inline. */
2823 /* Bail out if we can't compute strlen in the right mode. */
2825 {
2829 }
2833 /* Make a place to hold the source address. We will not expand
2834 the actual source until we are sure that the expansion will
2835 not fail -- there are trees that cannot be expanded twice. */
2838 /* Mark the beginning of the strlen sequence so we can emit the
2839 source operand later. */
2849 /* Now that we are assured of success, expand the source. */
2853 {
2854 #ifdef POINTERS_EXTEND_UNSIGNED
2857 POINTERS_EXTEND_UNSIGNED);
2858 #endif
2860 }
2866 else
2869 /* Return the value in the proper mode for this function. */
2874 else
2878 }
2879 }
2881 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
2882 bytes from constant string DATA + OFFSET and return it as target
2883 constant. */
2885 static rtx
2887 scalar_int_mode mode)
2888 {
2896 }
2898 /* LEN specify length of the block of memcpy/memset operation.
2899 Figure out its range and put it into MIN_SIZE/MAX_SIZE.
2900 In some cases we can make very likely guess on max size, then we
2901 set it into PROBABLE_MAX_SIZE. */
2903 static void
2908 {
2910 {
2913 }
2914 else
2915 {
2919 /* Determine bounds from the type. */
2922 else
2927 else
2933 {
2938 }
2940 {
2941 /* Anti range 0...N lets us to determine minimal size to N+1. */
2943 {
2946 }
2947 /* Code like
2949 int n;
2950 if (n < 100)
2951 memcpy (a, b, n)
2953 Produce anti range allowing negative values of N. We still
2954 can use the information and make a guess that N is not negative.
2955 */
2958 }
2959 }
2963 }
2965 /* Try to verify that the sizes and lengths of the arguments to a string
2966 manipulation function given by EXP are within valid bounds and that
2967 the operation does not lead to buffer overflow. Arguments other than
2968 EXP may be null. When non-null, the arguments have the following
2969 meaning:
2970 SIZE is the user-supplied size argument to the function (such as in
2971 memcpy(d, s, SIZE) or strncpy(d, s, SIZE). It specifies the exact
2972 number of bytes to write.
2973 MAXLEN is the user-supplied bound on the length of the source sequence
2974 (such as in strncat(d, s, N). It specifies the upper limit on the number
2975 of bytes to write.
2976 SRC is the source string (such as in strcpy(d, s)) when the expression
2977 EXP is a string function call (as opposed to a memory call like memcpy).
2978 As an exception, SRC can also be an integer denoting the precomputed
2979 size of the source string or object (for functions like memcpy).
2980 OBJSIZE is the size of the destination object specified by the last
2981 argument to the _chk builtins, typically resulting from the expansion
2982 of __builtin_object_size (such as in __builtin___strcpy_chk(d, s,
2983 OBJSIZE).
2985 When SIZE is null LEN is checked to verify that it doesn't exceed
2986 SIZE_MAX.
2988 If the call is successfully verified as safe from buffer overflow
2989 the function returns true, otherwise false.. */
2991 static bool
2993 {
2994 /* The size of the largest object is half the address space, or
2995 SSIZE_MAX. (This is way too permissive.) */
3002 /* Set to true when the exact number of bytes written by a string
3003 function like strcpy is not known and the only thing that is
3004 known is that it must be at least one (for the terminating nul). */
3007 {
3008 /* SRC is normally a pointer to string but as a special case
3009 it can be an integer denoting the length of a string. */
3011 {
3012 /* Try to determine the range of lengths the source string
3013 refers to. If it can be determined and is less than
3014 the upper bound given by MAXLEN add one to it for
3015 the terminating nul. Otherwise, set it to one for
3016 the same reason, or to MAXLEN as appropriate. */
3019 {
3022 else
3033 }
3034 else
3035 {
3038 }
3039 }
3040 else
3042 }
3045 {
3046 /* When the only available piece of data is the object size
3047 there is nothing to do. */
3051 /* Otherwise, when the length of the source sequence is known
3052 (as with with strlen), set SIZE to it. */
3055 }
3060 /* The SIZE is exact if it's non-null, constant, and in range of
3061 unsigned HOST_WIDE_INT. */
3067 /* First check the number of bytes to be written against the maximum
3068 object size. */
3070 {
3076 "%K%qD specified size %E "
3079 else
3081 "%K%qD specified size between %E and %E "
3086 }
3088 /* Next check the number of bytes to be written against the destination
3089 object size. */
3091 {
3097 {
3102 {
3103 /* This is a call to strcpy with a destination of 0 size
3104 and a source of unknown length. The call will write
3105 at least one byte past the end of the destination. */
3107 "%K%qD writing %E or more bytes into a region "
3110 }
3120 {
3121 /* Avoid printing the upper bound if it's invalid. */
3123 "%K%qD writing %E or more bytes into a region "
3126 }
3127 else
3129 "%K%qD writing between %E and %E bytes into "
3132 objsize);
3134 /* Return error when an overflow has been detected. */
3136 }
3137 }
3139 /* Check the maximum length of the source sequence against the size
3140 of the destination object if known, or against the maximum size
3141 of an object. */
3143 {
3147 {
3152 {
3153 /* Warn about crazy big sizes first since that's more
3154 likely to be meaningful than saying that the bound
3155 is greater than the object size if both are big. */
3158 "%K%qD specified bound %E "
3162 else
3164 "%K%qD specified bound between %E and %E "
3170 }
3173 {
3176 "%K%qD specified bound %E "
3180 else
3182 "%K%qD specified bound between %E and %E "
3187 }
3188 }
3189 }
3195 {
3205 {
3206 /* Avoid printing the upper bound if it's invalid. */
3208 "%K%qD reading %E or more bytes from a region "
3211 }
3212 else
3214 "%K%qD reading between %E and %E bytes from a region "
3218 }
3221 }
3223 /* Helper to compute the size of the object referenced by the DEST
3224 expression which must of of pointer type, using Object Size type
3225 OSTYPE (only the least significant 2 bits are used). Return
3226 the size of the object if successful or NULL when the size cannot
3227 be determined. */
3231 {
3237 }
3239 /* Helper to determine and check the sizes of the source and the destination
3240 of calls to __builtin_{bzero,memcpy,mempcpy,memset} calls. EXP is the
3241 call expression, DEST is the destination argument, SRC is the source
3242 argument or null, and LEN is the number of bytes. Use Object Size type-0
3243 regardless of the OPT_Wstringop_overflow_ setting. Return true on success
3244 (no overflow or invalid sizes), false otherwise. */
3246 static bool
3248 {
3252 /* For functions like memset and memcpy that operate on raw memory
3253 try to determine the size of the largest source and destination
3254 object using type-0 Object Size regardless of the object size
3255 type specified by the option. */
3261 }
3263 /* Validate memchr arguments without performing any expansion.
3264 Return NULL_RTX. */
3266 static rtx
3268 {
3276 /* Diagnose calls where the specified length exceeds the size
3277 of the object. */
3279 {
3284 }
3287 }
3289 /* Expand a call EXP to the memcpy builtin.
3290 Return NULL_RTX if we failed, the caller should emit a normal call,
3291 otherwise try to get the result in TARGET, if convenient (and in
3292 mode MODE if that's convenient). */
3294 static rtx
3296 {
3309 }
3311 /* Check a call EXP to the memmove built-in for validity.
3312 Return NULL_RTX on both success and failure. */
3314 static rtx
3316 {
3328 }
3330 /* Expand an instrumented call EXP to the memcpy builtin.
3331 Return NULL_RTX if we failed, the caller should emit a normal call,
3332 otherwise try to get the result in TARGET, if convenient (and in
3333 mode MODE if that's convenient). */
3335 static rtx
3337 {
3343 else
3344 {
3351 /* Return src bounds with the result. */
3353 {
3357 }
3359 }
3360 }
3362 /* Expand a call EXP to the mempcpy builtin.
3363 Return NULL_RTX if we failed; the caller should emit a normal call,
3364 otherwise try to get the result in TARGET, if convenient (and in
3365 mode MODE if that's convenient). If ENDP is 0 return the
3366 destination pointer, if ENDP is 1 return the end pointer ala
3367 mempcpy, and if ENDP is 2 return the end pointer minus one ala
3368 stpcpy. */
3370 static rtx
3372 {
3381 /* Avoid expanding mempcpy into memcpy when the call is determined
3382 to overflow the buffer. This also prevents the same overflow
3383 from being diagnosed again when expanding memcpy. */
3389 }
3391 /* Expand an instrumented call EXP to the mempcpy builtin.
3392 Return NULL_RTX if we failed, the caller should emit a normal call,
3393 otherwise try to get the result in TARGET, if convenient (and in
3394 mode MODE if that's convenient). */
3396 static rtx
3398 {
3404 else
3405 {
3412 /* Return src bounds with the result. */
3414 {
3418 }
3420 }
3421 }
3423 /* Helper function to do the actual work for expand of memory copy family
3424 functions (memcpy, mempcpy, stpcpy). Expansing should assign LEN bytes
3425 of memory from SRC to DEST and assign to TARGET if convenient.
3426 If ENDP is 0 return the
3427 destination pointer, if ENDP is 1 return the end pointer ala
3428 mempcpy, and if ENDP is 2 return the end pointer minus one ala
3429 stpcpy. */
3431 static rtx
3434 {
3445 /* If DEST is not a pointer type, call the normal function. */
3449 /* If either SRC is not a pointer type, don't do this
3450 operation in-line. */
3467 /* If SRC is a string constant and block move would be done
3468 by pieces, we can avoid loading the string from memory
3469 and only stored the computed constants. */
3476 {
3478 builtin_memcpy_read_str,
3484 }
3489 /* Copy word part most expediently. */
3498 {
3501 }
3504 {
3506 /* stpcpy pointer to last byte. */
3509 }
3512 }
3514 static rtx
3517 {
3519 endp);
3520 }
3522 /* Expand into a movstr instruction, if one is available. Return NULL_RTX if
3523 we failed, the caller should emit a normal call, otherwise try to
3524 get the result in TARGET, if convenient. If ENDP is 0 return the
3525 destination pointer, if ENDP is 1 return the end pointer ala
3526 mempcpy, and if ENDP is 2 return the end pointer minus one ala
3527 stpcpy. */
3529 static rtx
3531 {
3533 rtx dest_mem;
3534 rtx src_mem;
3542 {
3545 }
3554 {
3556 /* movstr is supposed to set end to the address of the NUL
3557 terminator. If the caller requested a mempcpy-like return value,
3558 adjust it. */
3560 {
3564 }
3565 }
3567 }
3569 /* Do some very basic size validation of a call to the strcpy builtin
3570 given by EXP. Return NULL_RTX to have the built-in expand to a call
3571 to the library function. */
3573 static rtx
3575 {
3583 /* There is no way here to determine the length of the string in
3584 the destination to which the SRC string is being appended so
3585 just diagnose cases when the souce string is longer than
3586 the destination object. */
3594 }
3596 /* Expand expression EXP, which is a call to the strcpy builtin. Return
3597 NULL_RTX if we failed the caller should emit a normal call, otherwise
3598 try to get the result in TARGET, if convenient (and in mode MODE if that's
3599 convenient). */
3601 static rtx
3603 {
3611 {
3615 }
3618 }
3620 /* Helper function to do the actual work for expand_builtin_strcpy. The
3621 arguments to the builtin_strcpy call DEST and SRC are broken out
3622 so that this can also be called without constructing an actual CALL_EXPR.
3623 The other arguments and return value are the same as for
3624 expand_builtin_strcpy. */
3626 static rtx
3628 {
3630 }
3632 /* Expand a call EXP to the stpcpy builtin.
3633 Return NULL_RTX if we failed the caller should emit a normal call,
3634 otherwise try to get the result in TARGET, if convenient (and in
3635 mode MODE if that's convenient). */
3637 static rtx
3639 {
3650 {
3654 }
3656 /* If return value is ignored, transform stpcpy into strcpy. */
3658 {
3662 }
3663 else
3664 {
3666 rtx ret;
3668 /* Ensure we get an actual string whose length can be evaluated at
3669 compile-time, not an expression containing a string. This is
3670 because the latter will potentially produce pessimized code
3671 when used to produce the return value. */
3683 {
3687 {
3691 {
3693 {
3696 else
3698 }
3707 }
3708 }
3709 }
3712 }
3713 }
3715 /* Check a call EXP to the stpncpy built-in for validity.
3716 Return NULL_RTX on both success and failure. */
3718 static rtx
3720 {
3726 /* The source and destination of the call. */
3730 /* The exact number of bytes to write (not the maximum). */
3733 /* The size of the destination object. */
3740 }
3742 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
3743 bytes from constant string DATA + OFFSET and return it as target
3744 constant. */
3746 rtx
3748 scalar_int_mode mode)
3749 {
3756 }
3758 /* Helper to check the sizes of sequences and the destination of calls
3759 to __builtin_strncat and __builtin___strncat_chk. Returns true on
3760 success (no overflow or invalid sizes), false otherwise. */
3762 static bool
3764 {
3769 /* Try to determine the range of lengths that the source expression
3770 refers to. */
3774 /* Try to verify that the destination is big enough for the shortest
3775 string. */
3778 {
3779 /* If it hasn't been provided by __strncat_chk, try to determine
3780 the size of the destination object into which the source is
3781 being copied. */
3783 }
3785 /* Add one for the terminating nul. */
3788 size_one_node)
3791 /* Strncat copies at most MAXLEN bytes and always appends the terminating
3792 nul so the specified upper bound should never be equal to (or greater
3793 than) the size of the destination. */
3796 {
3805 }
3813 /* The number of bytes to write is LEN but check_sizes will also
3814 check SRCLEN if LEN's value isn't known. */
3817 }
3819 /* Similar to expand_builtin_strcat, do some very basic size validation
3820 of a call to the strcpy builtin given by EXP. Return NULL_RTX to have
3821 the built-in expand to a call to the library function. */
3823 static rtx
3825 {
3833 /* The upper bound on the number of bytes to write. */
3835 /* The length of the source sequence. */
3838 /* Try to determine the range of lengths that the source expression
3839 refers to. */
3843 else
3846 /* Try to verify that the destination is big enough for the shortest
3847 string. First try to determine the size of the destination object
3848 into which the source is being copied. */
3851 /* Add one for the terminating nul. */
3854 size_one_node)
3857 /* Strncat copies at most MAXLEN bytes and always appends the terminating
3858 nul so the specified upper bound should never be equal to (or greater
3859 than) the size of the destination. */
3862 {
3871 }
3879 /* The number of bytes to write is LEN but check_sizes will also
3880 check SRCLEN if LEN's value isn't known. */
3885 }
3887 /* Expand expression EXP, which is a call to the strncpy builtin. Return
3888 NULL_RTX if we failed the caller should emit a normal call. */
3890 static rtx
3892 {
3897 {
3900 /* The number of bytes to write (not the maximum). */
3902 /* The length of the source sequence. */
3906 {
3910 /* The number of bytes to write is LEN but check_sizes will also
3911 check SLEN if LEN's value isn't known. */
3914 }
3916 /* We must be passed a constant len and src parameter. */
3922 /* We're required to pad with trailing zeros if the requested
3923 len is greater than strlen(s2)+1. In that case try to
3924 use store_by_pieces, if it fails, punt. */
3926 {
3929 rtx dest_mem;
3933 builtin_strncpy_read_str,
3940 builtin_strncpy_read_str,
3945 }
3946 }
3948 }
3950 /* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
3951 bytes from constant string DATA + OFFSET and return it as target
3952 constant. */
3954 rtx
3956 scalar_int_mode mode)
3957 {
3964 }
3966 /* Callback routine for store_by_pieces. Return the RTL of a register
3967 containing GET_MODE_SIZE (MODE) consecutive copies of the unsigned
3968 char value given in the RTL register data. For example, if mode is
3969 4 bytes wide, return the RTL for 0x01010101*data. */
3971 static rtx
3973 scalar_int_mode mode)
3974 {
3990 }
3992 /* Expand expression EXP, which is a call to the memset builtin. Return
3993 NULL_RTX if we failed the caller should emit a normal call, otherwise
3994 try to get the result in TARGET, if convenient (and in mode MODE if that's
3995 convenient). */
3997 static rtx
3999 {
4011 }
4013 /* Expand expression EXP, which is an instrumented call to the memset builtin.
4014 Return NULL_RTX if we failed the caller should emit a normal call, otherwise
4015 try to get the result in TARGET, if convenient (and in mode MODE if that's
4016 convenient). */
4018 static rtx
4020 {
4025 else
4026 {
4032 /* Return src bounds with the result. */
4034 {
4038 }
4040 }
4041 }
4043 /* Helper function to do the actual work for expand_builtin_memset. The
4044 arguments to the builtin_memset call DEST, VAL, and LEN are broken out
4045 so that this can also be called without constructing an actual CALL_EXPR.
4046 The other arguments and return value are the same as for
4047 expand_builtin_memset. */
4049 static rtx
4052 {
4055 machine_mode val_mode;
4067 /* If DEST is not a pointer type, don't do this operation in-line. */
4078 /* If the LEN parameter is zero, return DEST. */
4080 {
4081 /* Evaluate and ignore VAL in case it has side-effects. */
4084 }
4086 /* Stabilize the arguments in case we fail. */
4098 {
4099 rtx val_rtx;
4104 /* Assume that we can memset by pieces if we can store
4105 * the coefficients by pieces (in the required modes).
4106 * We can't pass builtin_memset_gen_str as that emits RTL. */
4112 {
4117 }
4121 probable_max_size))
4127 }
4133 {
4144 probable_max_size))
4150 }
4158 probable_max_size);
4161 {
4164 }
4168 do_libcall:
4178 else
4183 }
4185 /* Expand expression EXP, which is a call to the bzero builtin. Return
4186 NULL_RTX if we failed the caller should emit a normal call. */
4188 static rtx
4190 {
4199 /* New argument list transforming bzero(ptr x, int y) to
4200 memset(ptr x, int 0, size_t y). This is done this way
4201 so that if it isn't expanded inline, we fallback to
4202 calling bzero instead of memset. */
4210 }
4212 /* Try to expand cmpstr operation ICODE with the given operands.
4213 Return the result rtx on success, otherwise return null. */
4215 static rtx
4217 HOST_WIDE_INT align)
4218 {
4232 }
4234 /* Expand expression EXP, which is a call to the memcmp built-in function.
4235 Return NULL_RTX if we failed and the caller should emit a normal call,
4236 otherwise try to get the result in TARGET, if convenient.
4237 RESULT_EQ is true if we can relax the returned value to be either zero
4238 or nonzero, without caring about the sign. */
4240 static rtx
4242 {
4251 /* Diagnose calls where the specified length exceeds the size of either
4252 object. */
4254 {
4259 {
4264 }
4265 }
4273 /* If we don't have POINTER_TYPE, call the function. */
4281 /* Set MEM_SIZE as appropriate. */
4283 {
4286 }
4292 {
4296 }
4298 /* If SRC is a string constant and block move would be done
4299 by pieces, we can avoid loading the string from memory
4300 and only stored the computed constants. */
4312 {
4313 /* Return the value in the proper mode for this function. */
4318 {
4321 }
4324 }
4327 }
4329 /* Expand expression EXP, which is a call to the strcmp builtin. Return NULL_RTX
4330 if we failed the caller should emit a normal call, otherwise try to get
4331 the result in TARGET, if convenient. */
4333 static rtx
4335 {
4342 {
4352 /* If we don't have POINTER_TYPE, call the function. */
4356 /* Stabilize the arguments in case gen_cmpstr(n)si fail. */
4363 /* Try to call cmpstrsi. */
4368 /* Try to determine at least one length and call cmpstrnsi. */
4370 {
4371 tree len;
4372 rtx arg3_rtx;
4382 /* If we don't have a constant length for the first, use the length
4383 of the second, if we know it. We don't require a constant for
4384 this case; some cost analysis could be done if both are available
4385 but neither is constant. For now, assume they're equally cheap,
4386 unless one has side effects. If both strings have constant lengths,
4387 use the smaller. */
4403 else
4406 /* If both arguments have side effects, we cannot optimize. */
4408 {
4410 result = expand_cmpstrn_or_cmpmem
4413 }
4414 }
4417 {
4418 /* Return the value in the proper mode for this function. */
4426 }
4428 /* Expand the library call ourselves using a stabilized argument
4429 list to avoid re-evaluating the function's arguments twice. */
4435 }
4437 }
4439 /* Expand expression EXP, which is a call to the strncmp builtin. Return
4440 NULL_RTX if we failed the caller should emit a normal call, otherwise try to get
4441 the result in TARGET, if convenient. */
4443 static rtx
4445 ATTRIBUTE_UNUSED machine_mode mode)
4446 {
4453 /* If c_strlen can determine an expression for one of the string
4454 lengths, and it doesn't have side effects, then emit cmpstrnsi
4455 using length MIN(strlen(string)+1, arg3). */
4458 {
4461 rtx result;
4480 /* If we don't have a constant length for the first, use the length
4481 of the second, if we know it. If neither string is constant length,
4482 use the given length argument. We don't require a constant for
4483 this case; some cost analysis could be done if both are available
4484 but neither is constant. For now, assume they're equally cheap,
4485 unless one has side effects. If both strings have constant lengths,
4486 use the smaller. */
4504 else
4507 /* If we are not using the given length, we must incorporate it here.
4508 The actual new length parameter will be MIN(len,arg3) in this case. */
4518 {
4519 /* Return the value in the proper mode for this function. */
4527 }
4529 /* Expand the library call ourselves using a stabilized argument
4530 list to avoid re-evaluating the function's arguments twice. */
4537 }
4539 }
4541 /* Expand a call to __builtin_saveregs, generating the result in TARGET,
4542 if that's convenient. */
4544 rtx
4546 {
4547 rtx val;
4550 /* Don't do __builtin_saveregs more than once in a function.
4551 Save the result of the first call and reuse it. */
4555 /* When this function is called, it means that registers must be
4556 saved on entry to this function. So we migrate the call to the
4557 first insn of this function. */
4561 /* Do whatever the machine needs done in this case. */
4569 /* Put the insns after the NOTE that starts the function. If this
4570 is inside a start_sequence, make the outer-level insn chain current, so
4571 the code is placed at the start of the function. */
4577 }
4579 /* Expand a call to __builtin_next_arg. */
4581 static rtx
4583 {
4584 /* Checking arguments is already done in fold_builtin_next_arg
4585 that must be called before this function. */
4590 }
4592 /* Make it easier for the backends by protecting the valist argument
4593 from multiple evaluations. */
4595 static tree
4597 {
4600 /* The current way of determining the type of valist is completely
4601 bogus. We should have the information on the va builtin instead. */
4606 {
4610 /* For this case, the backends will be expecting a pointer to
4611 vatype, but it's possible we've actually been given an array
4612 (an actual TARGET_CANONICAL_VA_LIST_TYPE (valist)).
4613 So fix it. */
4615 {
4618 }
4619 }
4620 else
4621 {
4625 {
4631 }
4637 }
4640 }
4642 /* The "standard" definition of va_list is void*. */
4644 tree
4646 {
4648 }
4650 /* The "standard" abi va_list is va_list_type_node. */
4652 tree
4654 {
4656 }
4658 /* The "standard" type of va_list is va_list_type_node. */
4660 tree
4662 {
4669 {
4670 /* If va_list is an array type, the argument may have decayed
4671 to a pointer type, e.g. by being passed to another function.
4672 In that case, unwrap both types so that we can compare the
4673 underlying records. */
4676 {
4679 }
4680 }
4685 }
4687 /* The "standard" implementation of va_start: just assign `nextarg' to
4688 the variable. */
4690 void
4692 {
4696 /* We do not have any valid bounds for the pointer, so
4697 just store zero bounds for it. */
4701 nextarg));
4702 }
4704 /* Expand EXP, a call to __builtin_va_start. */
4706 static rtx
4708 {
4709 rtx nextarg;
4710 tree valist;
4714 {
4717 }
4727 else
4731 }
4733 /* Expand EXP, a call to __builtin_va_end. */
4735 static rtx
4737 {
4740 /* Evaluate for side effects, if needed. I hate macros that don't
4741 do that. */
4746 }
4748 /* Expand EXP, a call to __builtin_va_copy. We do this as a
4749 builtin rather than just as an assignment in stdarg.h because of the
4750 nastiness of array-type va_list types. */
4752 static rtx
4754 {
4767 {
4771 }
4772 else
4773 {
4776 /* Evaluate to pointers. */
4785 /* "Dereference" to BLKmode memories. */
4793 /* Copy. */
4795 }
4798 }
4800 /* Expand a call to one of the builtin functions __builtin_frame_address or
4801 __builtin_return_address. */
4803 static rtx
4805 {
4806 /* The argument must be a nonnegative integer constant.
4807 It counts the number of frames to scan up the stack.
4808 The value is either the frame pointer value or the return
4809 address saved in that frame. */
4811 /* Warning about missing arg was already issued. */
4814 {
4817 }
4818 else
4819 {
4820 /* Number of frames to scan up the stack. */
4825 /* Some ports cannot access arbitrary stack frames. */
4827 {
4830 }
4833 {
4834 /* Warn since no effort is made to ensure that any frame
4835 beyond the current one exists or can be safely reached. */
4838 }
4840 /* For __builtin_frame_address, return what we've got. */
4848 }
4849 }
4851 /* Expand EXP, a call to the alloca builtin. Return NULL_RTX if we
4852 failed and the caller should emit a normal call. */
4854 static rtx
4856 {
4857 rtx op0;
4858 rtx result;
4861 HOST_WIDE_INT max_size;
4864 bool valid_arglist
4867 VOID_TYPE)
4877 {
4878 /* -Walloca-larger-than and -Wvla-larger-than settings override
4879 the more general -Walloc-size-larger-than so unless either of
4880 the former options is specified check the alloca arguments for
4881 overflow. */
4885 }
4887 /* Compute the argument. */
4890 /* Compute the alignment. */
4892 ? BIGGEST_ALIGNMENT
4895 /* Compute the maximum size. */
4900 /* Allocate the desired space. If the allocation stems from the declaration
4901 of a variable-sized object, it cannot accumulate. */
4902 result
4907 }
4909 /* Emit a call to __asan_allocas_unpoison call in EXP. Replace second argument
4910 of the call with virtual_stack_dynamic_rtx because in asan pass we emit a
4911 dummy value into second parameter relying on this function to perform the
4912 change. See motivation for this in comment to handle_builtin_stack_restore
4913 function. */
4915 static rtx
4917 {
4925 }
4927 /* Expand a call to bswap builtin in EXP.
4928 Return NULL_RTX if a normal call should be emitted rather than expanding the
4929 function in-line. If convenient, the result should be placed in TARGET.
4930 SUBTARGET may be used as the target for computing one of EXP's operands. */
4932 static rtx
4934 rtx subtarget)
4935 {
4936 tree arg;
4937 rtx op0;
4955 }
4957 /* Expand a call to a unary builtin in EXP.
4958 Return NULL_RTX if a normal call should be emitted rather than expanding the
4959 function in-line. If convenient, the result should be placed in TARGET.
4960 SUBTARGET may be used as the target for computing one of EXP's operands. */
4962 static rtx
4965 {
4966 rtx op0;
4971 /* Compute the argument. */
4973 (subtarget
4977 /* Compute op, into TARGET if possible.
4978 Set TARGET to wherever the result comes back. */
4984 }
4986 /* Expand a call to __builtin_expect. We just return our argument
4987 as the builtin_expect semantic should've been already executed by
4988 tree branch prediction pass. */
4990 static rtx
4992 {
4993 tree arg;
5000 /* When guessing was done, the hints should be already stripped away. */
5004 }
5006 /* Expand a call to __builtin_assume_aligned. We just return our first
5007 argument as the builtin_assume_aligned semantic should've been already
5008 executed by CCP. */
5010 static rtx
5012 {
5016 EXPAND_NORMAL);
5021 }
5023 void
5025 {
5027 {
5029 /* For trap insns when not accumulating outgoing args force
5030 REG_ARGS_SIZE note to prevent crossjumping of calls with
5031 different args sizes. */
5034 }
5035 else
5036 {
5040 }
5043 }
5045 /* Expand a call to __builtin_unreachable. We do nothing except emit
5046 a barrier saying that control flow will not pass here.
5048 It is the responsibility of the program being compiled to ensure
5049 that control flow does never reach __builtin_unreachable. */
5050 static void
5052 {
5054 }
5056 /* Expand EXP, a call to fabs, fabsf or fabsl.
5057 Return NULL_RTX if a normal call should be emitted rather than expanding
5058 the function inline. If convenient, the result should be placed
5059 in TARGET. SUBTARGET may be used as the target for computing
5060 the operand. */
5062 static rtx
5064 {
5065 machine_mode mode;
5066 tree arg;
5067 rtx op0;
5077 }
5079 /* Expand EXP, a call to copysign, copysignf, or copysignl.
5080 Return NULL is a normal call should be emitted rather than expanding the
5081 function inline. If convenient, the result should be placed in TARGET.
5082 SUBTARGET may be used as the target for computing the operand. */
5084 static rtx
5086 {
5088 tree arg;
5100 }
5102 /* Expand a call to __builtin___clear_cache. */
5104 static rtx
5106 {
5108 {
5109 #ifdef CLEAR_INSN_CACHE
5110 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
5111 does something. Just do the default expansion to a call to
5112 __clear_cache(). */
5114 #else
5115 /* There is no "clear_cache" insn, and __clear_cache() in libgcc
5116 does nothing. There is no need to call it. Do nothing. */
5119 }
5121 /* We have a "clear_cache" insn, and it will handle everything. */
5125 /* We must not expand to a library call. If we did, any
5126 fallback library function in libgcc that might contain a call to
5127 __builtin___clear_cache() would recurse infinitely. */
5129 {
5132 }
5135 {
5148 }
5150 }
5152 /* Given a trampoline address, make sure it satisfies TRAMPOLINE_ALIGNMENT. */
5154 static rtx
5156 {
5159 /* If we don't need too much alignment, we'll have been guaranteed
5160 proper alignment by get_trampoline_type. */
5164 /* Round address up to desired boundary. */
5175 }
5177 static rtx
5179 {
5195 /* If ONSTACK, the TRAMP argument should be the address of a field
5196 within the local function's FRAME decl. Either way, let's see if
5197 we can fill in the MEM_ATTRs for this memory. */
5201 /* Creator of a heap trampoline is responsible for making sure the
5202 address is aligned to at least STACK_BOUNDARY. Normally malloc
5203 will ensure this anyhow. */
5206 {
5210 }
5212 /* The FUNC argument should be the address of the nested function.
5213 Extract the actual function decl to pass to the hook. */
5220 /* Generate insns to initialize the trampoline. */
5224 {
5230 }
5233 }
5235 static rtx
5237 {
5238 rtx tramp;
5249 }
5251 /* Expand a call to the builtin descriptor initialization routine.
5252 A descriptor is made up of a couple of pointers to the static
5253 chain and the code entry in this order. */
5255 static rtx
5257 {
5262 VOID_TYPE))
5276 /* Generate insns to initialize the descriptor. */
5282 }
5284 /* Expand a call to the builtin descriptor adjustment routine. */
5286 static rtx
5288 {
5289 rtx tramp;
5296 /* Unalign the descriptor to allow runtime identification. */
5301 }
5303 /* Expand the call EXP to the built-in signbit, signbitf or signbitl
5304 function. The function first checks whether the back end provides
5305 an insn to implement signbit for the respective mode. If not, it
5306 checks whether the floating point format of the value is such that
5307 the sign bit can be extracted. If that is not the case, error out.
5308 EXP is the expression that is a call to the builtin function; if
5309 convenient, the result should be placed in TARGET. */
5310 static rtx
5312 {
5314 scalar_float_mode fmode;
5316 tree arg;
5319 rtx temp;
5332 /* Expand the argument yielding a RTX expression. */
5335 /* Check if the back end provides an insn that handles signbit for the
5336 argument's mode. */
5339 {
5345 }
5347 /* For floating point formats without a sign bit, implement signbit
5348 as "ARG < 0.0". */
5351 {
5352 /* But we can't do this if the format supports signed zero. */
5358 }
5361 {
5364 }
5365 else
5366 {
5368 /* Handle targets with different FP word orders. */
5371 else
5375 }
5377 /* Force the intermediate word_mode (or narrower) result into a
5378 register. This avoids attempting to create paradoxical SUBREGs
5379 of floating point modes below. */
5382 /* If the bitpos is within the "result mode" lowpart, the operation
5383 can be implement with a single bitwise AND. Otherwise, we need
5384 a right shift and an AND. */
5387 {
5395 }
5396 else
5397 {
5398 /* Perform a logical right shift to place the signbit in the least
5399 significant bit, then truncate the result to the desired mode
5400 and mask just this bit. */
5405 }
5408 }
5410 /* Expand fork or exec calls. TARGET is the desired target of the
5411 call. EXP is the call. FN is the
5412 identificator of the actual function. IGNORE is nonzero if the
5413 value is to be ignored. */
5415 static rtx
5417 {
5419 tree call;
5421 /* If we are not profiling, just call the function. */
5425 /* Otherwise call the wrapper. This should be equivalent for the rest of
5426 compiler, so the code does not diverge, and the wrapper may run the
5427 code necessary for keeping the profiling sane. */
5430 {
5461 }
5473 }
5476 \f
5477 /* Reconstitute a mode for a __sync intrinsic operation. Since the type of
5478 the pointer in these functions is void*, the tree optimizers may remove
5479 casts. The mode computed in expand_builtin isn't reliable either, due
5480 to __sync_bool_compare_and_swap.
5482 FCODE_DIFF should be fcode - base, where base is the FOO_1 code for the
5483 group of builtins. This gives us log2 of the mode size. */
5487 {
5488 /* The size is not negotiable, so ask not to get BLKmode in return
5489 if the target indicates that a smaller size would be better. */
5491 }
5493 /* Expand the memory expression LOC and return the appropriate memory operand
5494 for the builtin_sync operations. */
5496 static rtx
5498 {
5504 /* Note that we explicitly do not want any alias information for this
5505 memory, so that we kill all other live memories. Otherwise we don't
5506 satisfy the full barrier semantics of the intrinsic. */
5509 /* The alignment needs to be at least according to that of the mode. */
5516 }
5518 /* Make sure an argument is in the right mode.
5519 EXP is the tree argument.
5520 MODE is the mode it should be in. */
5522 static rtx
5524 {
5525 rtx val;
5526 machine_mode old_mode;
5529 /* If VAL is promoted to a wider mode, convert it back to MODE. Take care
5530 of CONST_INTs, where we know the old_mode only from the call argument. */
5537 }
5540 /* Expand the __sync_xxx_and_fetch and __sync_fetch_and_xxx intrinsics.
5541 EXP is the CALL_EXPR. CODE is the rtx code
5542 that corresponds to the arithmetic or logical operation from the name;
5543 an exception here is that NOT actually means NAND. TARGET is an optional
5544 place for us to store the results; AFTER is true if this is the
5545 fetch_and_xxx form. */
5547 static rtx
5550 rtx target)
5551 {
5556 {
5563 {
5592 }
5593 }
5595 /* Expand the operands. */
5600 after);
5601 }
5603 /* Expand the __sync_val_compare_and_swap and __sync_bool_compare_and_swap
5604 intrinsics. EXP is the CALL_EXPR. IS_BOOL is
5605 true if this is the boolean form. TARGET is a place for us to store the
5606 results; this is NOT optional if IS_BOOL is true. */
5608 static rtx
5611 {
5615 /* Expand the operands. */
5622 {
5625 else
5627 }
5630 MEMMODEL_SYNC_SEQ_CST))
5634 }
5636 /* Expand the __sync_lock_test_and_set intrinsic. Note that the most
5637 general form is actually an atomic exchange, and some targets only
5638 support a reduced form with the second argument being a constant 1.
5639 EXP is the CALL_EXPR; TARGET is an optional place for us to store
5640 the results. */
5642 static rtx
5644 rtx target)
5645 {
5648 /* Expand the operands. */
5653 }
5655 /* Expand the __sync_lock_release intrinsic. EXP is the CALL_EXPR. */
5657 static void
5659 {
5660 rtx mem;
5662 /* Expand the operands. */
5666 }
5668 /* Given an integer representing an ``enum memmodel'', verify its
5669 correctness and return the memory model enum. */
5671 static enum memmodel
5673 {
5674 rtx op;
5676 source_location loc
5679 /* If the parameter is not a constant, it's a run time value so we'll just
5680 convert it to MEMMODEL_SEQ_CST to avoid annoying runtime checking. */
5690 {
5694 }
5696 /* Should never see a user explicit SYNC memodel model, so >= LAST works. */
5698 {
5702 }
5704 /* Workaround for Bugzilla 59448. GCC doesn't track consume properly, so
5705 be conservative and promote consume to acquire. */
5710 }
5712 /* Expand the __atomic_exchange intrinsic:
5713 TYPE __atomic_exchange (TYPE *object, TYPE desired, enum memmodel)
5714 EXP is the CALL_EXPR.
5715 TARGET is an optional place for us to store the results. */
5717 static rtx
5719 {
5728 /* Expand the operands. */
5733 }
5735 /* Expand the __atomic_compare_exchange intrinsic:
5736 bool __atomic_compare_exchange (TYPE *object, TYPE *expect,
5737 TYPE desired, BOOL weak,
5738 enum memmodel success,
5739 enum memmodel failure)
5740 EXP is the CALL_EXPR.
5741 TARGET is an optional place for us to store the results. */
5743 static rtx
5745 rtx target)
5746 {
5750 tree weak;
5752 source_location loc
5759 {
5761 "failure memory model cannot be stronger than success "
5764 }
5767 {
5769 "invalid failure memory model for "
5773 }
5779 /* Expand the operands. */
5795 /* Lest the rtl backend create a race condition with an imporoper store
5796 to memory, always create a new pseudo for OLDVAL. */
5803 /* Conditionally store back to EXPECT, lest we create a race condition
5804 with an improper store to memory. */
5805 /* ??? With a rearrangement of atomics at the gimple level, we can handle
5806 the normal case where EXPECT is totally private, i.e. a register. At
5807 which point the store can be unconditional. */
5815 }
5817 /* Helper function for expand_ifn_atomic_compare_exchange - expand
5818 internal ATOMIC_COMPARE_EXCHANGE call into __atomic_compare_exchange_N
5819 call. The weak parameter must be dropped to match the expected parameter
5820 list and the expected argument changed from value to pointer to memory
5821 slot. */
5823 static void
5825 {
5841 /* Skip the boolean weak parameter. */
5844 built_in_function fncode
5849 fndecl);
5854 {
5861 }
5862 }
5864 /* Expand IFN_ATOMIC_COMPARE_EXCHANGE internal function. */
5866 void
5868 {
5874 tree lhs;
5876 source_location loc
5883 {
5885 "failure memory model cannot be stronger than success "
5888 }
5891 {
5893 "invalid failure memory model for "
5897 }
5900 {
5903 }
5905 /* Expand the operands. */
5918 {
5921 }
5925 {
5931 }
5932 }
5934 /* Expand the __atomic_load intrinsic:
5935 TYPE __atomic_load (TYPE *object, enum memmodel)
5936 EXP is the CALL_EXPR.
5937 TARGET is an optional place for us to store the results. */
5939 static rtx
5941 {
5942 rtx mem;
5947 {
5948 source_location loc
5953 }
5958 /* Expand the operand. */
5962 }
5965 /* Expand the __atomic_store intrinsic:
5966 void __atomic_store (TYPE *object, TYPE desired, enum memmodel)
5967 EXP is the CALL_EXPR.
5968 TARGET is an optional place for us to store the results. */
5970 static rtx
5972 {
5979 {
5980 source_location loc
5985 }
5990 /* Expand the operands. */
5995 }
5997 /* Expand the __atomic_fetch_XXX intrinsic:
5998 TYPE __atomic_fetch_XXX (TYPE *object, TYPE val, enum memmodel)
5999 EXP is the CALL_EXPR.
6000 TARGET is an optional place for us to store the results.
6001 CODE is the operation, PLUS, MINUS, ADD, XOR, or IOR.
6002 FETCH_AFTER is true if returning the result of the operation.
6003 FETCH_AFTER is false if returning the value before the operation.
6004 IGNORE is true if the result is not used.
6005 EXT_CALL is the correct builtin for an external call if this cannot be
6006 resolved to an instruction sequence. */
6008 static rtx
6012 {
6015 tree fndecl;
6016 tree addr;
6020 /* Expand the operands. */
6024 /* Only try generating instructions if inlining is turned on. */
6026 {
6030 }
6032 /* Return if a different routine isn't needed for the library call. */
6036 /* Change the call to the specified function. */
6044 /* If we will emit code after the call, the call can not be a tail call.
6045 If it is emitted as a tail call, a barrier is emitted after it, and
6046 then all trailing code is removed. */
6050 /* Expand the call here so we can emit trailing code. */
6053 /* Replace the original function just in case it matters. */
6056 /* Then issue the arithmetic correction to return the right result. */
6058 {
6060 {
6062 OPTAB_LIB_WIDEN);
6064 }
6065 else
6067 OPTAB_LIB_WIDEN);
6068 }
6070 }
6072 /* Expand IFN_ATOMIC_BIT_TEST_AND_* internal function. */
6074 void
6076 {
6084 optab optab;
6096 {
6111 }
6114 {
6121 }
6143 {
6148 }
6149 else
6151 OPTAB_DIRECT);
6154 }
6156 /* Expand an atomic clear operation.
6157 void _atomic_clear (BOOL *obj, enum memmodel)
6158 EXP is the call expression. */
6160 static rtx
6162 {
6163 machine_mode mode;
6172 {
6173 source_location loc
6178 }
6180 /* Try issuing an __atomic_store, and allow fallback to __sync_lock_release.
6181 Failing that, a store is issued by __atomic_store. The only way this can
6182 fail is if the bool type is larger than a word size. Unlikely, but
6183 handle it anyway for completeness. Assume a single threaded model since
6184 there is no atomic support in this case, and no barriers are required. */
6189 }
6191 /* Expand an atomic test_and_set operation.
6192 bool _atomic_test_and_set (BOOL *obj, enum memmodel)
6193 EXP is the call expression. */
6195 static rtx
6197 {
6198 rtx mem;
6200 machine_mode mode;
6207 }
6210 /* Return true if (optional) argument ARG1 of size ARG0 is always lock free on
6211 this architecture. If ARG1 is NULL, use typical alignment for size ARG0. */
6213 static tree
6215 {
6217 machine_mode mode;
6223 /* We need a corresponding integer mode for the access to be lock-free. */
6231 {
6234 /* Either this argument is null, or it's a fake pointer encoding
6235 the alignment of the object. */
6241 else
6243 }
6244 else
6245 {
6248 /* This function is usually invoked and folded immediately by the front
6249 end before anything else has a chance to look at it. The pointer
6250 parameter at this point is usually cast to a void *, so check for that
6251 and look past the cast. */
6261 /* Get the underlying type of the object. */
6264 }
6266 /* If the object has smaller alignment, the lock free routines cannot
6267 be used. */
6271 /* Check if a compare_and_swap pattern exists for the mode which represents
6272 the required size. The pattern is not allowed to fail, so the existence
6273 of the pattern indicates support is present. Also require that an
6274 atomic load exists for the required size. */
6277 else
6279 }
6281 /* Return true if the parameters to call EXP represent an object which will
6282 always generate lock free instructions. The first argument represents the
6283 size of the object, and the second parameter is a pointer to the object
6284 itself. If NULL is passed for the object, then the result is based on
6285 typical alignment for an object of the specified size. Otherwise return
6286 false. */
6288 static rtx
6290 {
6291 tree size;
6296 {
6299 }
6305 }
6307 /* Return a one or zero if it can be determined that object ARG1 of size ARG
6308 is lock free on this architecture. */
6310 static tree
6312 {
6316 /* If it isn't always lock free, don't generate a result. */
6321 }
6323 /* Return true if the parameters to call EXP represent an object which will
6324 always generate lock free instructions. The first argument represents the
6325 size of the object, and the second parameter is a pointer to the object
6326 itself. If NULL is passed for the object, then the result is based on
6327 typical alignment for an object of the specified size. Otherwise return
6328 NULL*/
6330 static rtx
6332 {
6333 tree size;
6338 {
6341 }
6346 /* If the value is known at compile time, return the RTX for it. */
6352 }
6354 /* Expand the __atomic_thread_fence intrinsic:
6355 void __atomic_thread_fence (enum memmodel)
6356 EXP is the CALL_EXPR. */
6358 static void
6360 {
6363 }
6365 /* Expand the __atomic_signal_fence intrinsic:
6366 void __atomic_signal_fence (enum memmodel)
6367 EXP is the CALL_EXPR. */
6369 static void
6371 {
6374 }
6376 /* Expand the __sync_synchronize intrinsic. */
6378 static void
6380 {
6382 }
6384 static rtx
6386 {
6392 {
6394 /* If the target is not sutitable then create a new target. */
6402 }
6405 }
6407 static void
6409 {
6415 {
6422 }
6424 }
6426 \f
6427 /* Emit code to restore the current value of stack. */
6429 static void
6431 {
6443 }
6445 /* Emit code to save the current value of stack. */
6447 static rtx
6449 {
6454 }
6457 /* Expand an expression EXP that calls a built-in function,
6458 with result going to TARGET if that's convenient
6459 (and in mode MODE if that's convenient).
6460 SUBTARGET may be used as the target for computing one of EXP's operands.
6461 IGNORE is nonzero if the value is to be ignored. */
6463 rtx
6466 {
6475 /* When ASan is enabled, we don't want to expand some memory/string
6476 builtins and rely on libsanitizer's hooks. This allows us to avoid
6477 redundant checks and be sure, that possible overflow will be detected
6478 by ASan. */
6483 /* When not optimizing, generate calls to library functions for a certain
6484 set of builtins. */
6510 /* The built-in function expanders test for target == const0_rtx
6511 to determine whether the function's result will be ignored. */
6515 /* If the result of a pure or const built-in function is ignored, and
6516 none of its arguments are volatile, we can avoid expanding the
6517 built-in call and just evaluate the arguments for side-effects. */
6521 {
6523 tree arg;
6524 call_expr_arg_iterator iter;
6528 {
6531 }
6534 {
6538 }
6539 }
6541 /* expand_builtin_with_bounds is supposed to be used for
6542 instrumented builtin calls. */
6546 {
6564 /* Just do a normal library call if we were unable to fold
6565 the values. */
6641 /* __builtin_apply (FUNCTION, ARGUMENTS, ARGSIZE) invokes
6642 FUNCTION with a copy of the parameters described by
6643 ARGUMENTS, and ARGSIZE. It returns a block of memory
6644 allocated on the stack into which is stored all the registers
6645 that might possibly be used for returning the result of a
6646 function. ARGUMENTS is the value returned by
6647 __builtin_apply_args. ARGSIZE is the number of bytes of
6648 arguments that must be copied. ??? How should this value be
6649 computed? We'll also need a safe worst case value for varargs
6650 functions. */
6657 else
6658 {
6666 }
6668 /* __builtin_return (RESULT) causes the function to return the
6669 value described by RESULT. RESULT is address of the block of
6670 memory returned by __builtin_apply. */
6680 /* All valid uses of __builtin_va_arg_pack () are removed during
6681 inlining. */
6686 /* All valid uses of __builtin_va_arg_pack_len () are removed during
6687 inlining. */
6691 /* Return the address of the first anonymous stack arg. */
6713 /* Returns the address of the area where the structure is returned.
6714 0 otherwise. */
6720 else
6723 CASE_BUILT_IN_ALLOCA:
6886 {
6889 }
6893 /* This should have been lowered to the builtins below. */
6897 /* __builtin_setjmp_setup is passed a pointer to an array of five words
6898 and the receiver label. */
6900 {
6906 /* This is copied from the handling of non-local gotos. */
6908 nonlocal_goto_handler_labels
6910 nonlocal_goto_handler_labels);
6911 /* ??? Do not let expand_label treat us as such since we would
6912 not want to be both on the list of non-local labels and on
6913 the list of forced labels. */
6916 }
6920 /* __builtin_setjmp_receiver is passed the receiver label. */
6922 {
6928 }
6931 /* __builtin_longjmp is passed a pointer to an array of five words.
6932 It's similar to the C library longjmp function but works with
6933 __builtin_setjmp above. */
6936 {
6942 {
6945 }
6949 }
6958 /* This updates the setjmp buffer that is its argument with the value
6959 of the current stack pointer. */
6962 {
6963 rtx buf_addr
6968 }
6988 /* Various hooks for the DWARF 2 __throw routine. */
6994 #ifdef DWARF2_UNWIND_INFO
7000 #endif
7200 mode = get_builtin_sync_mode
7212 mode = get_builtin_sync_mode
7259 {
7263 mode =
7269 /* If this is turned into an external library call, the weak parameter
7270 must be dropped to match the expected parameter list. */
7275 /* Skip the boolean weak parameter. */
7280 }
7309 {
7319 }
7325 {
7335 }
7341 {
7351 }
7357 {
7367 }
7373 {
7383 }
7389 {
7399 }
7554 /* We allow user CHKP builtins if Pointer Bounds
7555 Checker is off. */
7557 {
7568 else
7570 }
7571 /* FALLTHROUGH */
7583 /* Software implementation of Pointer Bounds Checker is NYI.
7584 Target support is required. */
7589 /* Do library call, if we failed to expand the builtin when
7590 folding. */
7595 }
7597 /* The switch statement above can drop through to cause the function
7598 to be called normally. */
7600 }
7602 /* Similar to expand_builtin but is used for instrumented calls. */
7604 rtx
7606 rtx subtarget ATTRIBUTE_UNUSED,
7608 {
7621 {
7642 }
7644 /* The switch statement above can drop through to cause the function
7645 to be called normally. */
7647 }
7649 /* Determine whether a tree node represents a call to a built-in
7650 function. If the tree T is a call to a built-in function with
7651 the right number of arguments of the appropriate types, return
7652 the DECL_FUNCTION_CODE of the call, e.g. BUILT_IN_SQRT.
7653 Otherwise the return value is END_BUILTINS. */
7655 enum built_in_function
7657 {
7660 const_call_expr_arg_iterator iter;
7676 {
7677 /* If a function doesn't take a variable number of arguments,
7678 the last element in the list will have type `void'. */
7681 {
7685 }
7694 {
7697 }
7699 {
7702 }
7704 {
7707 }
7709 {
7712 }
7713 else
7715 }
7717 /* Variable-length argument list. */
7719 }
7721 /* Fold a call to __builtin_constant_p, if we know its argument ARG will
7722 evaluate to a constant. */
7724 static tree
7726 {
7727 /* We return 1 for a numeric type that's known to be a constant
7728 value at compile-time or for an aggregate type that's a
7729 literal constant. */
7732 /* If we know this is a constant, emit the constant of one. */
7738 {
7745 }
7747 /* If this expression has side effects, show we don't know it to be a
7748 constant. Likewise if it's a pointer or aggregate type since in
7749 those case we only want literals, since those are only optimized
7750 when generating RTL, not later.
7751 And finally, if we are compiling an initializer, not code, we
7752 need to return a definite result now; there's not going to be any
7753 more optimization done. */
7758 || folding_initializer
7763 }
7765 /* Create builtin_expect with PRED and EXPECTED as its arguments and
7766 return it as a truthvalue. */
7768 static tree
7770 tree predictor)
7771 {
7783 predictor);
7787 }
7789 /* Fold a call to builtin_expect with arguments ARG0 and ARG1. Return
7790 NULL_TREE if no simplification is possible. */
7792 tree
7794 {
7798 /* Distribute the expected value over short-circuiting operators.
7799 See through the cast from truthvalue_type_node to long. */
7806 /* If this is a builtin_expect within a builtin_expect keep the
7807 inner one. See through a comparison against a constant. It
7808 might have been added to create a thruthvalue. */
7824 {
7833 }
7835 /* If the argument isn't invariant then there's nothing else we can do. */
7839 /* If we expect that a comparison against the argument will fold to
7840 a constant return the constant. In practice, this means a true
7841 constant or the address of a non-weak symbol. */
7845 {
7846 do
7847 {
7849 }
7854 }
7856 /* Otherwise, ARG0 already has the proper type for the return value. */
7858 }
7860 /* Fold a call to __builtin_classify_type with argument ARG. */
7862 static tree
7864 {
7869 }
7871 /* Fold a call to __builtin_strlen with argument ARG. */
7873 static tree
7875 {
7878 else
7879 {
7886 }
7887 }
7889 /* Fold a call to __builtin_inf or __builtin_huge_val. */
7891 static tree
7893 {
7894 REAL_VALUE_TYPE real;
7896 /* __builtin_inff is intended to be usable to define INFINITY on all
7897 targets. If an infinity is not available, INFINITY expands "to a
7898 positive constant of type float that overflows at translation
7899 time", footnote "In this case, using INFINITY will violate the
7900 constraint in 6.4.4 and thus require a diagnostic." (C99 7.12#4).
7901 Thus we pedwarn to ensure this constraint violation is
7902 diagnosed. */
7908 }
7910 /* Fold function call to builtin sincos, sincosf, or sincosl. Return
7911 NULL_TREE if no simplification can be made. */
7913 static tree
7916 {
7917 tree type;
7927 /* Calculate the result when the argument is a constant. */
7932 /* Canonicalize sincos to cexpi. */
7934 {
7937 }
7939 {
7946 }
7955 }
7957 /* Fold function call to builtin memcmp with arguments ARG1 and ARG2.
7958 Return NULL_TREE if no simplification can be made. */
7960 static tree
7962 {
7968 /* If the LEN parameter is zero, return zero. */
7973 /* If ARG1 and ARG2 are the same (and not volatile), return zero. */
7977 /* If len parameter is one, return an expression corresponding to
7978 (*(const unsigned char*)arg1 - (const unsigned char*)arg2). */
7980 {
7982 tree cst_uchar_ptr_node
7985 tree ind1
7989 cst_uchar_ptr_node,
7990 arg1)));
7991 tree ind2
7995 cst_uchar_ptr_node,
7996 arg2)));
7998 }
8001 }
8003 /* Fold a call to builtin isascii with argument ARG. */
8005 static tree
8007 {
8010 else
8011 {
8012 /* Transform isascii(c) -> ((c & ~0x7f) == 0). */
8018 }
8019 }
8021 /* Fold a call to builtin toascii with argument ARG. */
8023 static tree
8025 {
8029 /* Transform toascii(c) -> (c & 0x7f). */
8032 }
8034 /* Fold a call to builtin isdigit with argument ARG. */
8036 static tree
8038 {
8041 else
8042 {
8043 /* Transform isdigit(c) -> (unsigned)(c) - '0' <= 9. */
8044 /* According to the C standard, isdigit is unaffected by locale.
8045 However, it definitely is affected by the target character set. */
8046 unsigned HOST_WIDE_INT target_digit0
8057 }
8058 }
8060 /* Fold a call to fabs, fabsf or fabsl with argument ARG. */
8062 static tree
8064 {
8070 }
8072 /* Fold a call to abs, labs, llabs or imaxabs with argument ARG. */
8074 static tree
8076 {
8082 }
8084 /* Fold a call to fma, fmaf, or fmal with arguments ARG[012]. */
8086 static tree
8088 {
8089 /* ??? Only expand to FMA_EXPR if it's directly supported. */
8097 }
8099 /* Fold a call to builtin carg(a+bi) -> atan2(b,a). */
8101 static tree
8103 {
8106 {
8110 {
8115 }
8116 }
8119 }
8121 /* Fold a call to builtin frexp, we can assume the base is 2. */
8123 static tree
8125 {
8136 /* Proceed if a valid pointer type was passed in. */
8138 {
8143 {
8145 /* For +-0, return (*exp = 0, +-0). */
8151 /* For +-NaN or +-Inf, *exp is unspecified, return arg0. */
8154 {
8155 /* Since the frexp function always expects base 2, and in
8156 GCC normalized significands are already in the range
8157 [0.5, 1.0), we have exactly what frexp wants. */
8162 }
8166 }
8168 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
8172 }
8175 }
8177 /* Fold a call to builtin modf. */
8179 static tree
8181 {
8192 /* Proceed if a valid pointer type was passed in. */
8194 {
8199 {
8202 /* For +-NaN or +-0, return (*arg1 = arg0, arg0). */
8206 /* For +-Inf, return (*arg1 = arg0, +-0). */
8212 /* Return (*arg1 = trunc(arg0), arg0-trunc(arg0)). */
8215 /* If the original number was negative and already
8216 integral, then the fractional part is -0.0. */
8220 }
8222 /* Create the COMPOUND_EXPR (*arg1 = trunc, frac). */
8228 }
8231 }
8233 /* Given a location LOC, an interclass builtin function decl FNDECL
8234 and its single argument ARG, return an folded expression computing
8235 the same, or NULL_TREE if we either couldn't or didn't want to fold
8236 (the latter happen if there's an RTL instruction available). */
8238 static tree
8240 {
8241 machine_mode mode;
8253 /* If there is no optab, try generic code. */
8255 {
8256 tree result;
8259 {
8260 /* isinf(x) -> isgreater(fabs(x),DBL_MAX). */
8263 REAL_VALUE_TYPE r;
8267 {
8268 /* NaN and Inf are encoded in the high-order double value
8269 only. The low-order value is not significant. */
8273 }
8280 }
8283 {
8284 /* isfinite(x) -> islessequal(fabs(x),DBL_MAX). */
8287 REAL_VALUE_TYPE r;
8291 {
8292 /* NaN and Inf are encoded in the high-order double value
8293 only. The low-order value is not significant. */
8297 }
8303 /*result = fold_build2_loc (loc, UNGT_EXPR,
8304 TREE_TYPE (TREE_TYPE (fndecl)),
8305 fold_build1_loc (loc, ABS_EXPR, type, arg),
8306 build_real (type, r));
8307 result = fold_build1_loc (loc, TRUTH_NOT_EXPR,
8308 TREE_TYPE (TREE_TYPE (fndecl)),
8309 result);*/
8311 }
8313 {
8314 /* isnormal(x) -> isgreaterequal(fabs(x),DBL_MIN) &
8315 islessequal(fabs(x),DBL_MAX). */
8325 {
8326 /* Use double to test the normal range of IBM extended
8327 precision. Emin for IBM extended precision is
8328 different to emin for IEEE double, being 53 higher
8329 since the low double exponent is at least 53 lower
8330 than the high double exponent. */
8334 }
8346 {
8347 /* Testing the high end of the range is done just using
8348 the high double, using the same test as isfinite().
8349 For the subnormal end of the range we first test the
8350 high double, then if its magnitude is equal to the
8351 limit of 0x1p-969, we test whether the low double is
8352 non-zero and opposite sign to the high double. */
8368 integer_type_node,
8374 }
8375 else
8376 {
8377 tree const isge_fn
8380 }
8384 }
8387 }
8390 }
8392 /* Fold a call to __builtin_isnan(), __builtin_isinf, __builtin_finite.
8393 ARG is the argument for the call. */
8395 static tree
8397 {
8404 {
8412 {
8413 /* isinf_sign(x) -> isinf(x) ? (signbit(x) ? -1 : 1) : 0 */
8414 /* In a boolean context, GCC will fold the inner COND_EXPR to
8415 1. So e.g. "if (isinf_sign(x))" would be folded to just
8416 "if (isinf(x) ? 1 : 0)" which becomes "if (isinf(x))". */
8424 {
8437 integer_zero_node);
8438 }
8441 }
8454 {
8457 {
8458 /* NaN and Inf are encoded in the high-order double value
8459 only. The low-order value is not significant. */
8461 }
8462 }
8468 }
8469 }
8471 /* Fold a call to __builtin_fpclassify(int, int, int, int, int, ...).
8472 This builtin will generate code to return the appropriate floating
8473 point classification depending on the value of the floating point
8474 number passed in. The possible return values must be supplied as
8475 int arguments to the call in the following order: FP_NAN, FP_INFINITE,
8476 FP_NORMAL, FP_SUBNORMAL and FP_ZERO. The ellipses is for exactly
8477 one floating point argument which is "type generic". */
8479 static tree
8481 {
8484 machine_mode mode;
8485 REAL_VALUE_TYPE r;
8488 /* Verify the required arguments in the original call. */
8508 /* fpclassify(x) ->
8509 isnan(x) ? FP_NAN :
8510 (fabs(x) == Inf ? FP_INFINITE :
8511 (fabs(x) >= DBL_MIN ? FP_NORMAL :
8512 (x == 0 ? FP_ZERO : FP_SUBNORMAL))). */
8526 {
8532 }
8535 {
8538 }
8541 }
8543 /* Fold a call to an unordered comparison function such as
8544 __builtin_isgreater(). FNDECL is the FUNCTION_DECL for the function
8545 being called and ARG0 and ARG1 are the arguments for the call.
8546 UNORDERED_CODE and ORDERED_CODE are comparison codes that give
8547 the opposite of the desired result. UNORDERED_CODE is used
8548 for modes that can hold NaNs and ORDERED_CODE is used for
8549 the rest. */
8551 static tree
8555 {
8569 /* Choose the wider of two real types. */
8581 {
8585 }
8590 }
8592 /* Fold __builtin_{,s,u}{add,sub,mul}{,l,ll}_overflow, either into normal
8593 arithmetics if it can never overflow, or into internal functions that
8594 return both result of arithmetics and overflowed boolean flag in
8595 a complex integer result, or some other check for overflow.
8596 Similarly fold __builtin_{add,sub,mul}_overflow_p to just the overflow
8597 checking part of that. */
8599 static tree
8602 {
8604 /* The code of the expression corresponding to the type-generic
8605 built-in, or ERROR_MARK for the type-specific ones. */
8610 {
8613 /* FALLTHRU */
8616 /* FALLTHRU */
8627 /* FALLTHRU */
8630 /* FALLTHRU */
8641 /* FALLTHRU */
8644 /* FALLTHRU */
8655 }
8657 /* For the "generic" overloads, the first two arguments can have different
8658 types and the last argument determines the target type to use to check
8659 for overflow. The arguments of the other overloads all have the same
8660 type. */
8663 /* For the __builtin_{add,sub,mul}_overflow_p builtins, when the first two
8664 arguments are constant, attempt to fold the built-in call into a constant
8665 expression indicating whether or not it detected an overflow. */
8669 /* Perform the computation in the target type and check for overflow. */
8673 arg2);
8687 tree store
8690 }
8692 /* Fold a call to __builtin_FILE to a constant string. */
8696 {
8701 }
8703 /* Fold a call to __builtin_FUNCTION to a constant string. */
8707 {
8714 }
8716 /* Fold a call to __builtin_LINE to an integer constant. */
8720 {
8722 }
8724 /* Fold a call to built-in function FNDECL with 0 arguments.
8725 This function returns NULL_TREE if no simplification was possible. */
8727 static tree
8729 {
8733 {
8759 }
8761 }
8763 /* Fold a call to built-in function FNDECL with 1 argument, ARG0.
8764 This function returns NULL_TREE if no simplification was possible. */
8766 static tree
8768 {
8779 {
8781 {
8784 /* Gimplification will pull the CALL_EXPR for the builtin out of
8785 an if condition. When not optimizing, we'll not CSE it back.
8786 To avoid link error types of regressions, return false now. */
8791 }
8847 {
8852 }
8858 {
8863 }
8884 }
8888 }
8890 /* Fold a call to built-in function FNDECL with 2 arguments, ARG0 and ARG1.
8891 This function returns NULL_TREE if no simplification was possible. */
8893 static tree
8895 {
8907 {
8951 NOP_EXPR);
8953 /* We do the folding for va_start in the expander. */
8968 }
8970 }
8972 /* Fold a call to built-in function FNDECL with 3 arguments, ARG0, ARG1,
8973 and ARG2.
8974 This function returns NULL_TREE if no simplification was possible. */
8976 static tree
8979 {
8993 {
9042 }
9044 }
9046 /* Fold a call to built-in function FNDECL. ARGS is an array of NARGS
9047 arguments. IGNORE is true if the result of the
9048 function call is ignored. This function returns NULL_TREE if no
9049 simplification was possible. */
9051 tree
9053 {
9057 {
9073 }
9075 {
9080 }
9082 }
9084 /* Construct a new CALL_EXPR to FNDECL using the tail of the argument
9085 list ARGS along with N new arguments in NEWARGS. SKIP is the number
9086 of arguments in ARGS to be omitted. OLDNARGS is the number of
9087 elements in ARGS. */
9089 static tree
9092 {
9097 {
9105 }
9106 else
9110 }
9112 /* Return true if FNDECL shouldn't be folded right now.
9113 If a built-in function has an inline attribute always_inline
9114 wrapper, defer folding it after always_inline functions have
9115 been inlined, otherwise e.g. -D_FORTIFY_SOURCE checking
9116 might not be performed. */
9118 bool
9120 {
9123 && cfun
9126 }
9128 /* A wrapper function for builtin folding that prevents warnings for
9129 "statement without effect" and the like, caused by removing the
9130 call node earlier than the warning is generated. */
9132 tree
9134 {
9140 /* If CALL_EXPR_VA_ARG_PACK is set, the arguments aren't finalized
9141 yet. Defer folding until we see all the arguments
9142 (after inlining). */
9144 {
9147 /* Before gimplification CALL_EXPR_VA_ARG_PACK is not set, but
9148 instead last argument is __builtin_va_arg_pack (). Defer folding
9149 even in that case, until arguments are finalized. */
9151 {
9158 }
9166 else
9167 {
9172 }
9173 }
9175 }
9177 /* Fold a CALL_EXPR with type TYPE with FN as the function expression.
9178 N arguments are passed in the array ARGARRAY. Return a folded
9179 expression or NULL_TREE if no simplification was possible. */
9181 tree
9183 tree fn,
9186 {
9193 {
9194 /* If last argument is __builtin_va_arg_pack (), arguments to this
9195 function are not finalized yet. Defer folding until they are. */
9197 {
9204 }
9209 else
9211 }
9214 }
9216 /* Construct a new CALL_EXPR using the tail of the argument list of EXP
9217 along with N new arguments specified as the "..." parameters. SKIP
9218 is the number of arguments in EXP to be omitted. This function is used
9219 to do varargs-to-varargs transformations. */
9221 static tree
9223 {
9225 tree t;
9233 }
9235 /* Validate a single argument ARG against a tree code CODE representing
9236 a type. Return true when argument is valid. */
9238 static bool
9240 {
9248 }
9250 /* This function validates the types of a function call argument list
9251 against a specified list of tree_codes. If the last specifier is a 0,
9252 that represents an ellipses, otherwise the last specifier must be a
9253 VOID_TYPE.
9255 This is the GIMPLE version of validate_arglist. Eventually we want to
9256 completely convert builtins.c to work from GIMPLEs and the tree based
9257 validate_arglist will then be removed. */
9259 bool
9261 {
9265 const_tree arg;
9271 do
9272 {
9275 {
9277 /* This signifies an ellipses, any further arguments are all ok. */
9281 /* This signifies an endlink, if no arguments remain, return
9282 true, otherwise return false. */
9286 /* If no parameters remain or the parameter's code does not
9287 match the specified code, return false. Otherwise continue
9288 checking any remaining arguments. */
9293 }
9294 }
9297 /* We need gotos here since we can only have one VA_CLOSE in a
9298 function. */
9299 end: ;
9303 }
9305 /* Default target-specific builtin expander that does nothing. */
9307 rtx
9309 rtx target ATTRIBUTE_UNUSED,
9310 rtx subtarget ATTRIBUTE_UNUSED,
9311 machine_mode mode ATTRIBUTE_UNUSED,
9313 {
9315 }
9317 /* Returns true is EXP represents data that would potentially reside
9318 in a readonly section. */
9320 bool
9322 {
9332 /* Make sure we call decl_readonly_section only for trees it
9333 can handle (since it returns true for everything it doesn't
9334 understand). */
9339 else
9341 }
9343 /* Simplify a call to the strpbrk builtin. S1 and S2 are the arguments
9344 to the call, and TYPE is its return type.
9346 Return NULL_TREE if no simplification was possible, otherwise return the
9347 simplified form of the call as a tree.
9349 The simplified form may be a constant or other expression which
9350 computes the same value, but in a more efficient manner (including
9351 calls to other builtin functions).
9353 The call may contain arguments which need to be evaluated, but
9354 which are not useful to determine the result of the call. In
9355 this case we return a chain of COMPOUND_EXPRs. The LHS of each
9356 COMPOUND_EXPR will be an argument which must be evaluated.
9357 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
9358 COMPOUND_EXPR in the chain will contain the tree for the simplified
9359 form of the builtin function call. */
9361 static tree
9363 {
9367 else
9368 {
9369 tree fn;
9378 {
9380 tree tem;
9385 /* Return an offset into the constant string argument. */
9388 }
9391 /* strpbrk(x, "") == NULL.
9392 Evaluate and ignore s1 in case it had side-effects. */
9402 /* New argument list transforming strpbrk(s1, s2) to
9403 strchr(s1, s2[0]). */
9406 }
9407 }
9409 /* Simplify a call to the strspn builtin. S1 and S2 are the arguments
9410 to the call.
9412 Return NULL_TREE if no simplification was possible, otherwise return the
9413 simplified form of the call as a tree.
9415 The simplified form may be a constant or other expression which
9416 computes the same value, but in a more efficient manner (including
9417 calls to other builtin functions).
9419 The call may contain arguments which need to be evaluated, but
9420 which are not useful to determine the result of the call. In
9421 this case we return a chain of COMPOUND_EXPRs. The LHS of each
9422 COMPOUND_EXPR will be an argument which must be evaluated.
9423 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
9424 COMPOUND_EXPR in the chain will contain the tree for the simplified
9425 form of the builtin function call. */
9427 static tree
9429 {
9433 else
9434 {
9437 /* If either argument is "", return NULL_TREE. */
9439 /* Evaluate and ignore both arguments in case either one has
9440 side-effects. */
9444 }
9445 }
9447 /* Simplify a call to the strcspn builtin. S1 and S2 are the arguments
9448 to the call.
9450 Return NULL_TREE if no simplification was possible, otherwise return the
9451 simplified form of the call as a tree.
9453 The simplified form may be a constant or other expression which
9454 computes the same value, but in a more efficient manner (including
9455 calls to other builtin functions).
9457 The call may contain arguments which need to be evaluated, but
9458 which are not useful to determine the result of the call. In
9459 this case we return a chain of COMPOUND_EXPRs. The LHS of each
9460 COMPOUND_EXPR will be an argument which must be evaluated.
9461 COMPOUND_EXPRs are chained through their RHS. The RHS of the last
9462 COMPOUND_EXPR in the chain will contain the tree for the simplified
9463 form of the builtin function call. */
9465 static tree
9467 {
9471 else
9472 {
9473 /* If the first argument is "", return NULL_TREE. */
9476 {
9477 /* Evaluate and ignore argument s2 in case it has
9478 side-effects. */
9481 }
9483 /* If the second argument is "", return __builtin_strlen(s1). */
9486 {
9489 /* If the replacement _DECL isn't initialized, don't do the
9490 transformation. */
9495 }
9497 }
9498 }
9500 /* Fold the next_arg or va_start call EXP. Returns true if there was an error
9501 produced. False otherwise. This is done so that we don't output the error
9502 or warning twice or three times. */
9504 bool
9506 {
9509 tree arg;
9510 /* There is good chance the current input_location points inside the
9511 definition of the va_start macro (perhaps on the token for
9512 builtin) in a system header, so warnings will not be emitted.
9513 Use the location in real source code. */
9514 source_location current_location =
9516 NULL);
9519 {
9522 }
9525 {
9527 {
9530 }
9532 }
9533 /* We use __builtin_va_start (ap, 0, 0) or __builtin_next_arg (0, 0)
9534 when we checked the arguments and if needed issued a warning. */
9535 else
9536 {
9538 {
9539 /* Evidently an out of date version of <stdarg.h>; can't validate
9540 va_start's second argument, but can still work as intended. */
9542 OPT_Wvarargs,
9545 }
9547 {
9550 }
9552 }
9557 /* We destructively modify the call to be __builtin_va_start (ap, 0)
9558 or __builtin_next_arg (0) the first time we see it, after checking
9559 the arguments and if needed issuing a warning. */
9561 {
9564 /* Strip off all nops for the sake of the comparison. This
9565 is not quite the same as STRIP_NOPS. It does more.
9566 We must also strip off INDIRECT_EXPR for C++ reference
9567 parameters. */
9572 {
9573 /* FIXME: Sometimes with the tree optimizers we can get the
9574 not the last argument even though the user used the last
9575 argument. We just warn and set the arg to be the last
9576 argument so that we will get wrong-code because of
9577 it. */
9579 OPT_Wvarargs,
9581 }
9583 /* Undefined by C99 7.15.1.4p4 (va_start):
9584 "If the parameter parmN is declared with the register storage
9585 class, with a function or array type, or with a type that is
9586 not compatible with the type that results after application of
9587 the default argument promotions, the behavior is undefined."
9588 */
9590 {
9592 OPT_Wvarargs,
9593 "undefined behavior when second parameter of "
9595 }
9597 /* We want to verify the second parameter just once before the tree
9598 optimizers are run and then avoid keeping it in the tree,
9599 as otherwise we could warn even for correct code like:
9600 void foo (int i, ...)
9601 { va_list ap; i++; va_start (ap, i); va_end (ap); } */
9604 else
9606 }
9608 }
9611 /* Expand a call EXP to __builtin_object_size. */
9613 static rtx
9615 {
9616 tree ost;
9621 {
9626 }
9634 {
9639 }
9644 }
9646 /* Expand EXP, a call to the __mem{cpy,pcpy,move,set}_chk builtin.
9647 FCODE is the BUILT_IN_* to use.
9648 Return NULL_RTX if we failed; the caller should emit a normal call,
9649 otherwise try to get the result in TARGET, if convenient (and in
9650 mode MODE if that's convenient). */
9652 static rtx
9655 {
9659 POINTER_TYPE,
9660 fcode == BUILT_IN_MEMSET_CHK
9678 {
9679 /* Avoid transforming the checking call to an ordinary one when
9680 an overflow has been detected or when the call couldn't be
9681 validated because the size is not constant. */
9686 /* If __builtin_mem{cpy,pcpy,move,set}_chk is used, assume
9687 mem{cpy,pcpy,move,set} is available. */
9689 {
9704 }
9713 }
9716 else
9717 {
9720 /* If DEST is not a pointer type, call the normal function. */
9724 /* If SRC and DEST are the same (and not volatile), do nothing. */
9726 {
9727 tree expr;
9730 {
9731 /* Evaluate and ignore LEN in case it has side-effects. */
9734 }
9738 }
9740 /* __memmove_chk special case. */
9742 {
9748 /* If src is categorized for a readonly section we can use
9749 normal __memcpy_chk. */
9751 {
9760 }
9761 }
9763 }
9764 }
9766 /* Emit warning if a buffer overflow is detected at compile time. */
9768 static void
9770 {
9771 /* The source string. */
9773 /* The size of the destination object. */
9775 /* The string that is being concatenated with (as in __strcat_chk)
9776 or null if it isn't. */
9778 /* The maximum length of the source sequence in a bounded operation
9779 (such as __strncat_chk) or null if the operation isn't bounded
9780 (such as __strcat_chk). */
9784 {
9792 /* For __strcat_chk the warning will be emitted only if overflowing
9793 by at least strlen (dest) + 1 bytes. */
9820 }
9823 {
9824 /* Check __strncat_chk. There is no way to determine the length
9825 of the string to which the source string is being appended so
9826 just warn when the length of the source string is not known. */
9829 }
9833 }
9835 /* Emit warning if a buffer overflow is detected at compile time
9836 in __sprintf_chk/__vsprintf_chk calls. */
9838 static void
9840 {
9845 /* Verify the required arguments in the original call. */
9855 /* Check whether the format is a literal string constant. */
9863 /* If the format doesn't contain % args or %%, we know its size. */
9866 /* If the format is "%s" and first ... argument is a string literal,
9867 we know it too. */
9870 {
9871 tree arg;
9882 }
9883 else
9886 /* Add one for the terminating nul. */
9890 }
9892 /* Emit warning if a free is called with address of a variable. */
9894 static void
9896 {
9910 else
9913 }
9915 /* Fold a call to __builtin_object_size with arguments PTR and OST,
9916 if possible. */
9918 static tree
9920 {
9937 /* __builtin_object_size doesn't evaluate side-effects in its arguments;
9938 if there are any side-effects, it returns (size_t) -1 for types 0 and 1
9939 and (size_t) 0 for types 2 and 3. */
9944 {
9948 }
9950 {
9951 /* If object size is not known yet, delay folding until
9952 later. Maybe subsequent passes will help determining
9953 it. */
9957 }
9960 }
9962 /* Builtins with folding operations that operate on "..." arguments
9963 need special handling; we need to store the arguments in a convenient
9964 data structure before attempting any folding. Fortunately there are
9965 only a few builtins that fall into this category. FNDECL is the
9966 function, EXP is the CALL_EXPR for the call. */
9968 static tree
9970 {
9975 {
9982 }
9984 {
9989 }
9991 }
9993 /* Initialize format string characters in the target charset. */
9995 bool
9997 {
10000 {
10023 }
10025 }
10027 /* Helper function for do_mpfr_arg*(). Ensure M is a normal number
10028 and no overflow/underflow occurred. INEXACT is true if M was not
10029 exactly calculated. TYPE is the tree type for the result. This
10030 function assumes that you cleared the MPFR flags and then
10031 calculated M to see if anything subsequently set a flag prior to
10032 entering this function. Return NULL_TREE if any checks fail. */
10034 static tree
10036 {
10037 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
10038 overflow/underflow occurred. If -frounding-math, proceed iff the
10039 result of calling FUNC was exact. */
10042 {
10043 REAL_VALUE_TYPE rr;
10046 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR value,
10047 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
10048 but the mpft_t is not, then we underflowed in the
10049 conversion. */
10052 {
10053 REAL_VALUE_TYPE rmode;
10056 /* Proceed iff the specified mode can hold the value. */
10059 }
10060 }
10062 }
10064 /* Helper function for do_mpc_arg*(). Ensure M is a normal complex
10065 number and no overflow/underflow occurred. INEXACT is true if M
10066 was not exactly calculated. TYPE is the tree type for the result.
10067 This function assumes that you cleared the MPFR flags and then
10068 calculated M to see if anything subsequently set a flag prior to
10069 entering this function. Return NULL_TREE if any checks fail, if
10070 FORCE_CONVERT is true, then bypass the checks. */
10072 static tree
10074 {
10075 /* Proceed iff we get a normal number, i.e. not NaN or Inf and no
10076 overflow/underflow occurred. If -frounding-math, proceed iff the
10077 result of calling FUNC was exact. */
10082 {
10087 /* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR values,
10088 check for overflow/underflow. If the REAL_VALUE_TYPE is zero
10089 but the mpft_t is not, then we underflowed in the
10090 conversion. */
10095 {
10100 /* Proceed iff the specified mode can hold the value. */
10106 }
10107 }
10109 }
10111 /* If arguments ARG0 and ARG1 are REAL_CSTs, call mpfr_remquo() to set
10112 the pointer *(ARG_QUO) and return the result. The type is taken
10113 from the type of ARG0 and is used for setting the precision of the
10114 calculation and results. */
10116 static tree
10118 {
10125 /* To proceed, MPFR must exactly represent the target floating point
10126 format, which only happens when the target base equals two. */
10130 {
10135 {
10139 tree result_rem;
10148 /* Remquo is independent of the rounding mode, so pass
10149 inexact=0 to do_mpfr_ckconv(). */
10153 {
10154 /* MPFR calculates quo in the host's long so it may
10155 return more bits in quo than the target int can hold
10156 if sizeof(host long) > sizeof(target int). This can
10157 happen even for native compilers in LP64 mode. In
10158 these cases, modulo the quo value with the largest
10159 number that the target int can hold while leaving one
10160 bit for the sign. */
10164 /* Dereference the quo pointer argument. */
10166 /* Proceed iff a valid pointer type was passed in. */
10168 {
10169 /* Set the value. */
10170 tree result_quo
10173 integer_quo));
10175 /* Combine the quo assignment with the rem. */
10178 }
10179 }
10180 }
10181 }
10183 }
10185 /* If ARG is a REAL_CST, call mpfr_lgamma() on it and return the
10186 resulting value as a tree with type TYPE. The mpfr precision is
10187 set to the precision of TYPE. We assume that this mpfr function
10188 returns zero if the result could be calculated exactly within the
10189 requested precision. In addition, the integer pointer represented
10190 by ARG_SG will be dereferenced and set to the appropriate signgam
10191 (-1,1) value. */
10193 static tree
10195 {
10200 /* To proceed, MPFR must exactly represent the target floating point
10201 format, which only happens when the target base equals two. Also
10202 verify ARG is a constant and that ARG_SG is an int pointer. */
10207 {
10210 /* In addition to NaN and Inf, the argument cannot be zero or a
10211 negative integer. */
10215 {
10220 mpfr_t m;
10221 tree result_lg;
10230 {
10231 tree result_sg;
10233 /* Dereference the arg_sg pointer argument. */
10235 /* Assign the signgam value into *arg_sg. */
10240 /* Combine the signgam assignment with the lgamma result. */
10243 }
10244 }
10245 }
10248 }
10250 /* If arguments ARG0 and ARG1 are a COMPLEX_CST, call the two-argument
10251 mpc function FUNC on it and return the resulting value as a tree
10252 with type TYPE. The mpfr precision is set to the precision of
10253 TYPE. We assume that function FUNC returns zero if the result
10254 could be calculated exactly within the requested precision. If
10255 DO_NONFINITE is true, then fold expressions containing Inf or NaN
10256 in the arguments and/or results. */
10258 tree
10261 {
10267 /* To proceed, MPFR must exactly represent the target floating point
10268 format, which only happens when the target base equals two. */
10274 {
10283 {
10303 }
10304 }
10307 }
10309 /* A wrapper function for builtin folding that prevents warnings for
10310 "statement without effect" and the like, caused by removing the
10311 call node earlier than the warning is generated. */
10313 tree
10315 {
10323 {
10332 {
10334 }
10335 else
10336 {
10339 {
10340 /* Propagate location information from original call to
10341 expansion of builtin. Otherwise things like
10342 maybe_emit_chk_warning, that operate on the expansion
10343 of a builtin, will use the wrong location information. */
10345 {
10353 }
10355 }
10356 }
10357 }
10359 }
10361 /* Look up the function in builtin_decl that corresponds to DECL
10362 and set ASMSPEC as its user assembler name. DECL must be a
10363 function decl that declares a builtin. */
10365 void
10367 {
10377 {
10381 }
10382 }
10384 /* Return true if DECL is a builtin that expands to a constant or similarly
10385 simple code. */
10386 bool
10388 {
10391 {
10392 /* Builtins that expand to constants. */
10397 /* Simple register moves or loads from stack. */
10408 /* Exception state returns or moves registers around. */
10416 }
10419 }
10421 /* Return true if DECL is a builtin that is not expensive, i.e., they are
10422 most probably expanded inline into reasonably simple code. This is a
10423 superset of is_simple_builtin. */
10424 bool
10426 {
10433 {
10435 CASE_BUILT_IN_ALLOCA:
10501 }
10504 }
10506 /* Return true if T is a constant and the value cast to a target char
10507 can be represented by a host char.
10508 Store the casted char constant in *P if so. */
10510 bool
10512 {
10518 }