[llvm] [X86] Fold vpmadd52h/l for pattern X * 0 + Y --> Y (PR #156086)

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``````````bash
git-clang-format --diff origin/main HEAD --extensions cpp -- llvm/lib/Target/X86/X86ISelLowering.cpp
``````````

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``````````diff
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 7c34d6614..d78cf00a5 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -44970,7 +44970,8 @@ bool X86TargetLowering::SimplifyDemandedBitsForTargetNode(
       return true;
 
     // X * 0 + Y --> Y
-    // TODO: Handle cases where lower/higher 52 of bits of Op0 * Op1 are known zeroes.
+    // TODO: Handle cases where lower/higher 52 of bits of Op0 * Op1 are known
+    // zeroes.
     if (KnownOp0.trunc(52).isZero() || KnownOp1.trunc(52).isZero())
       return TLO.CombineTo(Op, Op2);
 

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https://github.com/llvm/llvm-project/pull/156086