diff options
| author | Jakub Jelinek <jakub@redhat.com> | 2023-12-05 13:17:57 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2023-12-05 13:17:57 +0100 |
| commit | e0786ca9a18c50ad08c40936b228e325193664b8 (patch) | |
| tree | b437d5c537622dc1064814efa98725bdef3e82a9 | |
| parent | c1c267dfcdccd53af0d2b2c945794ab3b0d8683f (diff) | |
| download | gcc-e0786ca9a18c50ad08c40936b228e325193664b8.zip gcc-e0786ca9a18c50ad08c40936b228e325193664b8.tar.gz gcc-e0786ca9a18c50ad08c40936b228e325193664b8.tar.bz2 | |
i386: Fix -fcf-protection -Os ICE due to movabsq peephole2 [PR112845]
The following testcase ICEs in the movabsq $(i32 << shift), r64 peephole2
I've added a while back to use smaller code than movabsq if possible.
If i32 is 0xfa1e0ff3 and shift is not divisible by 8, then it creates
an invalid insn (as 0xfa1e0ff3 CONST_INT is not allowed as
x86_64_immediate_operand nor x86_64_zext_immediate_operand), the peephole2
even triggers on it again and again (this time with shift 0) until it gives
up.
The following patch fixes that. As ix86_endbr_immediate_operand needs a
CONST_INT and it is hopefully rare, I chose to use FAIL rather than handling
it in the condition (where I'd probably need to call ctz_hwi again etc.).
2023-12-05 Jakub Jelinek <jakub@redhat.com>
PR target/112845
* config/i386/i386.md (movabsq $(i32 << shift), r64 peephole2): FAIL
if the new immediate is ix86_endbr_immediate_operand.
| -rw-r--r-- | gcc/config/i386/i386.md | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr112845.c | 9 |
2 files changed, 13 insertions, 1 deletions
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index 7641b47..df7f917 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -2699,7 +2699,10 @@ (clobber (reg:CC FLAGS_REG))])] { int shift = ctz_hwi (UINTVAL (operands[1])); - operands[1] = gen_int_mode (UINTVAL (operands[1]) >> shift, DImode); + rtx op1 = gen_int_mode (UINTVAL (operands[1]) >> shift, DImode); + if (ix86_endbr_immediate_operand (op1, VOIDmode)) + FAIL; + operands[1] = op1; operands[2] = gen_int_mode (shift, QImode); }) diff --git a/gcc/testsuite/gcc.dg/pr112845.c b/gcc/testsuite/gcc.dg/pr112845.c new file mode 100644 index 0000000..ece6f45 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr112845.c @@ -0,0 +1,9 @@ +/* PR target/112845 */ +/* { dg-do compile { target cet } } */ +/* { dg-options "-Os -fcf-protection" } */ + +unsigned long long +foo (void) +{ + return 0xfa1e0ff3ULL << 3; +} |