[llvm] [AMDGPU] Avoid repeated hash lookups (NFC) (PR #111787)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-amdgpu

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/111787.diff


1 Files Affected:

- (modified) llvm/lib/Target/AMDGPU/R600ISelLowering.cpp (+6-4) 


``````````diff
diff --git a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
index 7e4d9d21a0b397..1b88fdd3ab2e1c 100644
--- a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
@@ -1647,16 +1647,18 @@ SDValue R600TargetLowering::OptimizeSwizzle(SDValue BuildVector, SDValue Swz[],
   BuildVector = CompactSwizzlableVector(DAG, BuildVector, SwizzleRemap);
   for (unsigned i = 0; i < 4; i++) {
     unsigned Idx = Swz[i]->getAsZExtVal();
-    if (SwizzleRemap.contains(Idx))
-      Swz[i] = DAG.getConstant(SwizzleRemap[Idx], DL, MVT::i32);
+    auto It = SwizzleRemap.find(Idx);
+    if (It != SwizzleRemap.end())
+      Swz[i] = DAG.getConstant(It->second, DL, MVT::i32);
   }
 
   SwizzleRemap.clear();
   BuildVector = ReorganizeVector(DAG, BuildVector, SwizzleRemap);
   for (unsigned i = 0; i < 4; i++) {
     unsigned Idx = Swz[i]->getAsZExtVal();
-    if (SwizzleRemap.contains(Idx))
-      Swz[i] = DAG.getConstant(SwizzleRemap[Idx], DL, MVT::i32);
+    auto It = SwizzleRemap.find(Idx);
+    if (It != SwizzleRemap.end())
+      Swz[i] = DAG.getConstant(It->second, DL, MVT::i32);
   }
 
   return BuildVector;

``````````

</details>


https://github.com/llvm/llvm-project/pull/111787