[llvm] [RISCV] Give up on correct undef semantics in mul strength reduction (PR #90097)

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git-clang-format --diff f4e3daa562ce077c729634bd3ae8757aae8d46ef cbcbe19fd94a42ab9106c1d0d7e5e67135bf1638 -- llvm/lib/Target/RISCV/RISCVISelLowering.cpp
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View the diff from clang-format here.
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diff --git a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
index 539aa35255..4f3317eb5f 100644
--- a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -13416,10 +13416,11 @@ static SDValue expandMul(SDNode *N, SelectionDAG &DAG,
     return SDValue();
   uint64_t MulAmt = CNode->getZExtValue();
 
-  // WARNING: The code below is knowingly incorrect with regards to undef semantics.
-  // We're adding additional uses of X here, and in principle, we should be freezing
-  // X before doing so.  However, adding freeze here causes real regressions, and no
-  // other target properly freezes X in these cases either.
+  // WARNING: The code below is knowingly incorrect with regards to undef
+  // semantics. We're adding additional uses of X here, and in principle, we
+  // should be freezing X before doing so.  However, adding freeze here causes
+  // real regressions, and no other target properly freezes X in these cases
+  // either.
   SDValue X = N->getOperand(0);
 
   for (uint64_t Divisor : {3, 5, 9}) {
@@ -13499,9 +13500,9 @@ static SDValue expandMul(SDNode *N, SelectionDAG &DAG,
       SDValue Shift1 =
           DAG.getNode(ISD::SHL, DL, VT, X,
                       DAG.getConstant(Log2_64(MulAmt + Offset), DL, VT));
-      SDValue Mul359 = DAG.getNode(RISCVISD::SHL_ADD, DL, VT, X,
-                                   DAG.getConstant(Log2_64(Offset - 1), DL, VT),
-                                   X);
+      SDValue Mul359 =
+          DAG.getNode(RISCVISD::SHL_ADD, DL, VT, X,
+                      DAG.getConstant(Log2_64(Offset - 1), DL, VT), X);
       return DAG.getNode(ISD::SUB, DL, VT, Shift1, Mul359);
     }
   }

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https://github.com/llvm/llvm-project/pull/90097