[llvm] Minor optimaze in visitFcmp (PR #156097)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: None (Seraphimt)

<details>
<summary>Changes</summary>

Studying the code related to float found a slightly optimal sequence of actions.

---
Full diff: https://github.com/llvm/llvm-project/pull/156097.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp (+3-3) 


``````````diff
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 3a8e043038153..90feddf6dcfe1 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -8944,14 +8944,14 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
   }
 
   {
-    Value *CanonLHS = nullptr, *CanonRHS = nullptr;
+    Value *CanonLHS = nullptr;
     match(Op0, m_Intrinsic<Intrinsic::canonicalize>(m_Value(CanonLHS)));
-    match(Op1, m_Intrinsic<Intrinsic::canonicalize>(m_Value(CanonRHS)));
-
     // (canonicalize(x) == x) => (x == x)
     if (CanonLHS == Op1)
       return new FCmpInst(Pred, Op1, Op1, "", &I);
 
+    Value *CanonRHS = nullptr;
+    match(Op1, m_Intrinsic<Intrinsic::canonicalize>(m_Value(CanonRHS)));
     // (x == canonicalize(x)) => (x == x)
     if (CanonRHS == Op0)
       return new FCmpInst(Pred, Op0, Op0, "", &I);

``````````

</details>


https://github.com/llvm/llvm-project/pull/156097