[llvm] [RISCV64] liveness analysis (PR #167454)

[Craig Topper via llvm-commits]

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@@ -629,6 +637,9 @@ void RISCVPassConfig::addPostRegAlloc() {
   if (TM->getOptLevel() != CodeGenOptLevel::None &&
       EnableRedundantCopyElimination)
     addPass(createRISCVRedundantCopyEliminationPass());
+
+  if (EnableRISCVLiveVariables)
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topperc wrote:

Do we need to run this for -O0?

https://github.com/llvm/llvm-project/pull/167454