diff options
| author | sayle <sayle@138bc75d-0d04-0410-961f-82ee72b054a4> | 2003-12-16 02:22:59 +0000 |
|---|---|---|
| committer | sayle <sayle@138bc75d-0d04-0410-961f-82ee72b054a4> | 2003-12-16 02:22:59 +0000 |
| commit | 5c8ef8c3944ede38b7b4bfa36c9c2697c050d999 (patch) | |
| tree | b02900d53cb5f257d74a47dcc26cadd3b2198c39 /gcc/ifcvt.c | |
| parent | d3d36188118a268c29a07839aced0771853130a7 (diff) | |
| download | gcc-5c8ef8c3944ede38b7b4bfa36c9c2697c050d999.tar.gz | |
PR middle-end/13400
* ifcvt.c (noce_process_if_block): Disable unconditional write
optimizations if we could introduce a store to trapping memory
that wasn't present previously.
* gcc.c-torture/execute/20031215-1.c: New test case.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@74663 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/ifcvt.c')
| -rw-r--r-- | gcc/ifcvt.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 4a13ba2a45b..8aba0d50efc 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -1965,6 +1965,25 @@ noce_process_if_block (struct ce_if_block * ce_info) goto success; } + /* Disallow the "if (...) x = a;" form (with an implicit "else x = x;") + for most optimizations if writing to x may trap, i.e. its a memory + other than a static var or a stack slot. */ + if (! set_b + && GET_CODE (orig_x) == MEM + && ! MEM_NOTRAP_P (orig_x) + && rtx_addr_can_trap_p (XEXP (orig_x, 0))) + { + if (HAVE_conditional_move) + { + if (noce_try_cmove (&if_info)) + goto success; + if (! HAVE_conditional_execution + && noce_try_cmove_arith (&if_info)) + goto success; + } + return FALSE; + } + if (noce_try_move (&if_info)) goto success; if (noce_try_store_flag (&if_info)) |