From ddefdc2aca6603f235b01d02f885d31e0971d8df Mon Sep 17 00:00:00 2001 From: hp Date: Fri, 31 Dec 2004 16:28:34 +0000 Subject: 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 --- gcc/combine.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'gcc/combine.c') 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 -- cgit v1.2.1