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| author | hp <hp@138bc75d-0d04-0410-961f-82ee72b054a4> | 2004-12-31 16:28:34 +0000 |
|---|---|---|
| committer | hp <hp@138bc75d-0d04-0410-961f-82ee72b054a4> | 2004-12-31 16:28:34 +0000 |
| commit | ddefdc2aca6603f235b01d02f885d31e0971d8df (patch) | |
| tree | e2ad4a12ed74c499257b5d0318e45ae551aa7b73 /gcc/combine.c | |
| parent | 9c61a71b065ed706f13a0a7069c52358554ae2e4 (diff) | |
| download | gcc-ddefdc2aca6603f235b01d02f885d31e0971d8df.tar.gz | |
PR target/18701
* combine.c (combine_simplify_rtx): Do not allow paradoxical
subregs of MEM.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@92762 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 61b93dd3048..90934e11672 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -3983,10 +3983,14 @@ combine_simplify_rtx (rtx x, enum machine_mode op0_mode, int in_dest) } /* Don't change the mode of the MEM if that would change the meaning - of the address. */ + of the address. Similarly, don't allow widening, as that may + access memory outside the defined object or using an address + that is invalid for a wider mode. */ if (MEM_P (SUBREG_REG (x)) && (MEM_VOLATILE_P (SUBREG_REG (x)) - || mode_dependent_address_p (XEXP (SUBREG_REG (x), 0)))) + || mode_dependent_address_p (XEXP (SUBREG_REG (x), 0)) + || (GET_MODE_SIZE (mode) + > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))))) return gen_rtx_CLOBBER (mode, const0_rtx); /* Note that we cannot do any narrowing for non-constants since |