[PATCH] D127871: [RISCV] Optimize 2x SELECT for floating-point types

[Liao Chunyu via Phabricator via llvm-commits]

liaolucy added inline comments.


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Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:9855
+  auto Next = next_nodbg(MI.getIterator(), BB->instr_end());
+  if (MI.getOpcode() != RISCV::Select_GPR_Using_CC_GPR && Next != BB->end() &&
+      Next->getOpcode() == MI.getOpcode() &&
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craig.topper wrote:
> I think we also need to make sure the condition for the second select doesn't use the output from the first select.
I'm still confused. You mean, should I need to add:  Next->getOperand(4).getReg() != MI.getOperand(0).getReg() ? 

But, the assembly of the bug.ll file has not changed. 



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  https://reviews.llvm.org/D127871/new/

https://reviews.llvm.org/D127871