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| author | Segher Boessenkool <segher@kernel.crashing.org> | 2016-05-14 01:01:40 +0200 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2016-05-14 01:01:40 +0200 |
| commit | 85ca20c9516879edf92356ee5d8a5c567db085a0 (patch) | |
| tree | 310b3ae6402e5929bff678da27c70f03f786eb77 /gcc/combine.c | |
| parent | aa4b467b680f230ab11922d1e29695e1eaba12af (diff) | |
| download | gcc-85ca20c9516879edf92356ee5d8a5c567db085a0.zip gcc-85ca20c9516879edf92356ee5d8a5c567db085a0.tar.gz gcc-85ca20c9516879edf92356ee5d8a5c567db085a0.tar.bz2 | |
combine: Don't call extract_left_shift with count < 0 (PR67483)
If the compiled program does a shift by a negative amount, combine will
happily work with that, but it shouldn't then do an undefined operation
in GCC itself. This patch fixes the first case mentioned in the bug
report (I haven't been able to reproduce the second case, on trunk at
least).
PR rtl-optimization/67483
* combine.c (make_compound_operation): Don't call extract_left_shift
with negative shift amounts.
From-SVN: r236232
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 3554f51..cd864cc 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -8037,6 +8037,7 @@ make_compound_operation (rtx x, enum rtx_code in_code) && ! (GET_CODE (lhs) == SUBREG && (OBJECT_P (SUBREG_REG (lhs)))) && CONST_INT_P (rhs) + && INTVAL (rhs) >= 0 && INTVAL (rhs) < HOST_BITS_PER_WIDE_INT && INTVAL (rhs) < mode_width && (new_rtx = extract_left_shift (lhs, INTVAL (rhs))) != 0) |