Displaying 2 results from an estimated 2 matches for "analyzecompare".
2016 Mar 10
2
[CodeGen] PeepholeOptimizer: optimizing condition dependent instrunctions
...ut CmpInstr. I simply go down and check all instructions which use AArch64::NZCV whether they can be substituted with the simpler version. After all I delete CmpInstr. This approach contradicts with PeepholeOptimizer design because BRC and SEL must be processed in corresponding functions. Yes, 'analyzeCompare' is cheap but in optimizeCondBranch and in optimizeSelect we need to go up to find the instruction defining condition flags. In case of BRC CMP should not be far from it but I am not sure about SEL. Also when BRC is replaced with BR CMP can be removed (BTW processing of instructions below BRC c...
2016 Mar 09
2
[CodeGen] PeepholeOptimizer: optimizing condition dependent instrunctions
Hi,
I find it's quite strange how condition dependent instructions are processed in PeepholeOptimizer::runOnMachineFunction:
01577 if ((isUncoalescableCopy(*MI) &&
01578 optimizeUncoalescableCopy(MI, LocalMIs)) ||
01579 (MI->isCompare() && optimizeCmpInstr(MI, &MBB)) ||
01580 (MI->isSelect() && optimizeSelect(MI,