https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117105
Bug ID: 117105
Summary: ICE on valid code at -O3 with "-fno-code-hoisting
-fno-tree-fre -fno-tree-dominator-opts -fno-tree-pre
-fno-tree-sra" on x86_64-linux-gnu: in
extract_constrain_insn, at recog.cc:2783
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zhendong.su at inf dot ethz.ch
Target Milestone: ---
It appears to be a recent regression as it doesn't reproduce with 14.2 and
earlier.
It might be related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115521.
Compiler Explorer: https://godbolt.org/z/bzcv7sdYd
[576] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/15.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 15.0.0 20241012 (experimental) (GCC)
[577] %
[577] % gcctk -O3 -fno-code-hoisting -fno-tree-fre -fno-tree-dominator-opts
-fno-tree-pre -fno-tree-sra small.c
small.c: In function ‘main’:
small.c:13:1: error: insn does not satisfy its constraints:
13 | }
| ^
(insn 24 55 54 4 (parallel [
(set (strict_low_part (reg:QI 2 cx [orig:109 e ] [109]))
(and:QI (subreg:QI (zero_extract:HI (reg/v:HI 2 cx [orig:109 e
] [109])
(const_int 8 [0x8])
(const_int 8 [0x8])) 0)
(reg:QI 1 dx [orig:115 _6 ] [115])))
(clobber (reg:CC 17 flags))
]) "small.c":11:15 728 {*andqi_exthi_1_slp}
(nil))
during RTL pass: reload
small.c:13:1: internal compiler error: in extract_constrain_insn, at
recog.cc:2783
0x2627345 internal_error(char const*, ...)
../../gcc-trunk/gcc/diagnostic-global-context.cc:517
0xa80f6e fancy_abort(char const*, int, char const*)
../../gcc-trunk/gcc/diagnostic.cc:1533
0x86bdf4 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
../../gcc-trunk/gcc/rtl-error.cc:108
0x86be20 _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
../../gcc-trunk/gcc/rtl-error.cc:118
0x86a05a extract_constrain_insn(rtx_insn*)
../../gcc-trunk/gcc/recog.cc:2783
0xfaccf7 check_rtl
../../gcc-trunk/gcc/lra.cc:2192
0xfb2191 lra(_IO_FILE*, int)
../../gcc-trunk/gcc/lra.cc:2613
0xf622ff do_reload
../../gcc-trunk/gcc/ira.cc:5977
0xf622ff execute
../../gcc-trunk/gcc/ira.cc:6165
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
[578] %
[578] % cat small.c
int a;
struct b {
char c;
char d;
};
int main() {
struct b e;
int f;
while (a)
if (f == e.d)
f = e.c = e.d & 1 >> e.d;
return 0;
}
