On 09/26/14 08:50, Jiong Wang wrote:
if (may_trap_p (x))
don't sink this instruction.
any comments?
Should be checking if x may throw internally instead.
Richard, thanks for the suggestion, have used insn_could_throw_p to do
the check,
which will only do the check when flag_exception and
flag_non_call_exception be true,
so those instruction could still be sink for normal c/c++ program.
Jeff,
below is the fix for pr49847.C regression on aarch64. I re-run
full test on
aarch64-none-elf bare metal, no regression.
bootstrap ok on x86, no regression on check-gcc/g++.
ok for trunk?
(re-sent with changelog entry)
gcc/
2014-09-26 Jiong Wang<jiong.w...@arm.com>
* shrink-wrap.c (move_insn_for_shrink_wrap): Check
"insn_could_throw_p" before
sinking insn.
I think can_throw_internal, per Richi's recommendation is better.
Note that can_throw_internal keys off the existence of the EH landing
pads for the particular insn.
If flag_exceptions is false (for example), then would not expect those
landing pads to exist and the insn would not be considered as
potentially throwing.
Can you test with can_throw_internal to verify it's behaviour and resubmit
jeff
