diff options
| author | Jakub Jelinek <jakub@redhat.com> | 2013-05-03 13:19:51 +0000 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2013-05-03 13:19:51 +0000 |
| commit | 0a91ddea3f1f9ec24436fcaf5a0d4b1db5da4ca9 (patch) | |
| tree | eebd3cd0571e56327e0f4974188185004d9abd66 /gcc/combine.c | |
| parent | e8fa6d72c34e7cea30a8179e7ae08a8ddcf8e2d3 (diff) | |
PR rtl-optimization/57130
* combine.c (make_compound_operation) <case SUBREG>: Pass
SET instead of COMPARE as in_code to the recursive call
if needed.
* gcc.c-torture/execute/pr57130.c: New test.
git-svn-id: https://gcc.gnu.org/svn/gcc/branches/gcc-4_8-branch@198581 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index acb74216589..a589cfadb42 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -7703,8 +7703,24 @@ make_compound_operation (rtx x, enum rtx_code in_code) what it originally did, do this SUBREG as a force_to_mode. */ { rtx inner = SUBREG_REG (x), simplified; - - tem = make_compound_operation (inner, in_code); + enum rtx_code subreg_code = in_code; + + /* If in_code is COMPARE, it isn't always safe to pass it through + to the recursive make_compound_operation call. */ + if (subreg_code == COMPARE + && (!subreg_lowpart_p (x) + || GET_CODE (inner) == SUBREG + /* (subreg:SI (and:DI (reg:DI) (const_int 0x800000000)) 0) + is (const_int 0), rather than + (subreg:SI (lshiftrt:DI (reg:DI) (const_int 35)) 0). */ + || (GET_CODE (inner) == AND + && CONST_INT_P (XEXP (inner, 1)) + && GET_MODE_SIZE (mode) < GET_MODE_SIZE (GET_MODE (inner)) + && exact_log2 (UINTVAL (XEXP (inner, 1))) + >= GET_MODE_BITSIZE (mode)))) + subreg_code = SET; + + tem = make_compound_operation (inner, subreg_code); simplified = simplify_subreg (mode, tem, GET_MODE (inner), SUBREG_BYTE (x)); |