diff options
| author | bstarynk <bstarynk@138bc75d-0d04-0410-961f-82ee72b054a4> | 2016-04-18 10:32:20 +0000 |
|---|---|---|
| committer | bstarynk <bstarynk@138bc75d-0d04-0410-961f-82ee72b054a4> | 2016-04-18 10:32:20 +0000 |
| commit | 523464ff57eea48adea62ae64f3dadc464250513 (patch) | |
| tree | 65f830a71da03bc6f1c2c25119de05ca0e685a8a /gcc/combine.c | |
| parent | 3fb2de4ac89890191b61d1d8a8b7b874ffebff19 (diff) | |
| download | gcc-523464ff57eea48adea62ae64f3dadc464250513.tar.gz | |
2016-04-18 Basile Starynkevitch <basile@starynkevitch.net>
{{merging with even more of GCC 6, using subversion 1.9
svn merge -r234051:234650 ^/trunk
}}
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@235119 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 24dcefa0bf6..1d0e8beeb2c 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -10524,9 +10524,24 @@ simplify_shift_const_1 (enum rtx_code code, machine_mode result_mode, && CONST_INT_P (XEXP (varop, 0)) && !CONST_INT_P (XEXP (varop, 1))) { + /* For ((unsigned) (cstULL >> count)) >> cst2 we have to make + sure the result will be masked. See PR70222. */ + if (code == LSHIFTRT + && mode != result_mode + && !merge_outer_ops (&outer_op, &outer_const, AND, + GET_MODE_MASK (result_mode) + >> orig_count, result_mode, + &complement_p)) + break; + /* For ((int) (cstLL >> count)) >> cst2 just give up. Queuing + up outer sign extension (often left and right shift) is + hardly more efficient than the original. See PR70429. */ + if (code == ASHIFTRT && mode != result_mode) + break; + rtx new_rtx = simplify_const_binary_operation (code, mode, - XEXP (varop, 0), - GEN_INT (count)); + XEXP (varop, 0), + GEN_INT (count)); varop = gen_rtx_fmt_ee (code, mode, new_rtx, XEXP (varop, 1)); count = 0; continue; |