This was previously returning int. However there are no negative opcode
numbers and more importantly this was needlessly different from
MCInstrDesc::getOpcode() (which even is the value returned here) and
SDValue::getOpcode()/SDNode::getOpcode().
llvm-svn: 237611
The CondOpt pass currently uses LiveIntervals to set the dead flag on a def. This patch uses MachineRegisterInfo::use_empty instead as that is equivalent to the def being dead.
This removes an instance of LiveIntervals in the pass manager pipeline and saves 3.8% of compile time on llc conpiled for AArch64.
Reviewed by Chad Rosier and Zhaoshi.
llvm-svn: 235532
Our internal test reveals such case should not be transformed:
cmp x17, #3
b.lt .LBB10_15
...
subs x12, x12, #1
b.gt .LBB10_1
where x12 is a liveout, becomes:
cmp x17, #2
b.le .LBB10_15
...
subs x12, x12, #2
b.ge .LBB10_1
Unable to provide test case as it's difficult to reproduce on community branch.
http://reviews.llvm.org/D6048
Patch by Zhaoshi Zheng <zhaoshiz@codeaurora.org>!
llvm-svn: 220987
Patched by Sergey Dmitrouk.
This pass tries to make consecutive compares of values use same operands to
allow CSE pass to remove duplicated instructions. For this it analyzes
branches and adjusts comparisons with immediate values by converting:
GE -> GT
GT -> GE
LT -> LE
LE -> LT
and adjusting immediate values appropriately. It basically corrects two
immediate values towards each other to make them equal.
llvm-svn: 217220
Matthias Braun