[AMDGPU] Avoid repeated hash lookups (NFC)

[kazutakahirata]

This patch just cleans up the "if" condition. Further cleanups are
left to subsequent patches.

[llvmbot]

@llvm/pr-subscribers-backend-amdgpu

Author: Kazu Hirata (kazutakahirata)

Changes

This patch just cleans up the "if" condition. Further cleanups are
left to subsequent patches.

---

Full diff: https://github.com/llvm/llvm-project/pull/126401.diff

1 Files Affected:

• (modified) llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp (+3-3)

diff --git a/llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp b/llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp
index f4e651ec477d30a..b8109db821bcc38 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp
@@ -367,11 +367,11 @@ bool LiveRegOptimizer::optimizeLiveType(
   for (Instruction *U : Uses) {
     // Replace all converted operands for a use.
     for (auto [OpIdx, Op] : enumerate(U->operands())) {
-      if (ValMap.contains(Op) && ValMap[Op]) {
+      if (Value *Val = ValMap.lookup(Op)) {
         Value *NewVal = nullptr;
         if (BBUseValMap.contains(U->getParent()) &&
-            BBUseValMap[U->getParent()].contains(ValMap[Op]))
-          NewVal = BBUseValMap[U->getParent()][ValMap[Op]];
+            BBUseValMap[U->getParent()].contains(Val))
+          NewVal = BBUseValMap[U->getParent()][Val];
         else {
           BasicBlock::iterator InsertPt = U->getParent()->getFirstNonPHIIt();
           // We may pick up ops that were previously converted for users in