[llvm] [InstCombine] Fold mul (shr exact (X, N)), 2^N + 1 -> add (X , shr exact (X, N)) (PR #112407)

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:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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``````````bash
git-clang-format --diff 6ef978b8c41a83378af3de1dceeea434715f80f4 19ecf328827d862db4feeae0716606641a3fc75d --extensions cpp -- llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
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<details>
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index dba6d1bba8..e787574058 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -260,28 +260,28 @@ Instruction *InstCombinerImpl::visitMul(BinaryOperator &I) {
     Value *NewOp;
     const APInt *ShiftC;
     const APInt *MulAP;
-    if (BitWidth > 2 && match(&I, m_Mul(m_Exact(m_Shr(m_Value(NewOp), m_APInt(ShiftC))),
-                        m_APInt(MulAP))) && (*MulAP - 1).isPowerOf2() &&
-          *ShiftC == MulAP->logBase2()) {
-        Value *BinOp = Op0;
-        BinaryOperator *OpBO = cast<BinaryOperator>(Op0);
-
-        // mul nuw (ashr exact X, N) -> add nuw (X, lshr exact (X, N))
-        if (HasNUW && OpBO->getOpcode() == Instruction::AShr &&
-            OpBO->hasOneUse())
-          BinOp = Builder.CreateLShr(NewOp, ConstantInt::get(Ty, *ShiftC), "",
-                                     /*isExact=*/true);
-
-        auto *NewAdd = BinaryOperator::CreateAdd(NewOp, BinOp);
-        if (HasNSW && (HasNUW || OpBO->getOpcode() == Instruction::LShr ||
-                       ShiftC->getZExtValue() < BitWidth - 1))
-          NewAdd->setHasNoSignedWrap(true);
-
-        NewAdd->setHasNoUnsignedWrap(HasNUW);
-        return NewAdd;
-      }
+    if (BitWidth > 2 &&
+        match(&I, m_Mul(m_Exact(m_Shr(m_Value(NewOp), m_APInt(ShiftC))),
+                        m_APInt(MulAP))) &&
+        (*MulAP - 1).isPowerOf2() && *ShiftC == MulAP->logBase2()) {
+      Value *BinOp = Op0;
+      BinaryOperator *OpBO = cast<BinaryOperator>(Op0);
+
+      // mul nuw (ashr exact X, N) -> add nuw (X, lshr exact (X, N))
+      if (HasNUW && OpBO->getOpcode() == Instruction::AShr && OpBO->hasOneUse())
+        BinOp = Builder.CreateLShr(NewOp, ConstantInt::get(Ty, *ShiftC), "",
+                                   /*isExact=*/true);
+
+      auto *NewAdd = BinaryOperator::CreateAdd(NewOp, BinOp);
+      if (HasNSW && (HasNUW || OpBO->getOpcode() == Instruction::LShr ||
+                     ShiftC->getZExtValue() < BitWidth - 1))
+        NewAdd->setHasNoSignedWrap(true);
+
+      NewAdd->setHasNoUnsignedWrap(HasNUW);
+      return NewAdd;
     }
   }
+}
 
   if (Op0->hasOneUse() && match(Op1, m_NegatedPower2())) {
     // Interpret  X * (-1<<C)  as  (-X) * (1<<C)  and try to sink the negation.

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https://github.com/llvm/llvm-project/pull/112407