[AMDGPU] Skip debug instructions when eliminating S_SET_GPR_IDX_ON/OFF #160715
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@llvm/pr-subscribers-backend-amdgpu Author: Jay Foad (jayfoad) ChangesFull diff: https://github.com/llvm/llvm-project/pull/160715.diff 2 Files Affected:
diff --git a/llvm/lib/Target/AMDGPU/SIPreEmitPeephole.cpp b/llvm/lib/Target/AMDGPU/SIPreEmitPeephole.cpp
index 4d3331ab353d3..96593cf5fb990 100644
--- a/llvm/lib/Target/AMDGPU/SIPreEmitPeephole.cpp
+++ b/llvm/lib/Target/AMDGPU/SIPreEmitPeephole.cpp
@@ -299,7 +299,7 @@ bool SIPreEmitPeephole::optimizeSetGPR(MachineInstr &First,
for (MachineBasicBlock::instr_iterator I = std::next(First.getIterator()),
E = MI.getIterator();
I != E; ++I) {
- if (I->isBundle())
+ if (I->isBundle() || I->isDebugInstr())
continue;
switch (I->getOpcode()) {
case AMDGPU::S_SET_GPR_IDX_MODE:
diff --git a/llvm/test/CodeGen/AMDGPU/set-gpr-idx-peephole.mir b/llvm/test/CodeGen/AMDGPU/set-gpr-idx-peephole.mir
index 002d43f937837..2cb3e9e95ed18 100644
--- a/llvm/test/CodeGen/AMDGPU/set-gpr-idx-peephole.mir
+++ b/llvm/test/CodeGen/AMDGPU/set-gpr-idx-peephole.mir
@@ -1,5 +1,6 @@
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple=amdgcn -mcpu=gfx900 -run-pass si-pre-emit-peephole -verify-machineinstrs -o - %s | FileCheck -check-prefix=GCN %s -implicit-check-not=S_SET_GPR_IDX
+# RUN: llc -mtriple=amdgcn -mcpu=gfx900 -run-pass si-pre-emit-peephole -verify-machineinstrs -o - %s -debugify-and-strip-all-safe | FileCheck -check-prefix=GCN %s -implicit-check-not=S_SET_GPR_IDX
# RUN: llc -mtriple=amdgcn -mcpu=gfx900 -passes si-pre-emit-peephole -o - %s | FileCheck -check-prefix=GCN %s -implicit-check-not=S_SET_GPR_IDX
---
|
| E = MI.getIterator(); | ||
| I != E; ++I) { | ||
| if (I->isBundle()) | ||
| if (I->isBundle() || I->isDebugInstr()) |
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Probably should be all meta instructions
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If you're doing that, also test KILL and IMPLICIT_DEF?
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Done for KILL. This is post-RA so I don't think we'll see IMPLICIT_DEF.
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IMPLICIT_DEF often survives RA, it is needed to maintain liveness across blocks
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You're right, I was confused. Added a test for IMPLICIT_DEF.
However, on reflection, I don't think explicitly skipping all meta instructions here is a good idea. Irrelevant instructions are already skipped below based on their operands, and I'm testing that this works for some meta instructions. Explicitly skipping all meta instructions seems unnecessary and possibly wrong.
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