[llvm] [InstCombine] Support division of numbers that can be converted to a shift (PR #88220)

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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 51f1681424f1a8ccf1e3432d71c341e799597171 7017287fbfcbd9b4d99d1f106f35aff88578b7f8 -- llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
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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 5b7454c034..ed7e873d6a 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -1165,21 +1165,21 @@ Instruction *InstCombinerImpl::commonIDivTransforms(BinaryOperator &I) {
         // Returns false if division by 0
         if (isMultiple(*C2, C3, Q, IsSigned) && Q.isPowerOf2()) {
           auto *OBO = cast<OverflowingBinaryOperator>(Op0);
-            APInt C4 = IsSigned ? C1->sdiv(C3) : C1->udiv(C3);
-            auto *Mul = Builder.CreateMul(
-                X, ConstantInt::get(Ty, C4), "",
-                // If it is unsigned, then we cannot have any nsw or nuw flags.
-                // It has been tried before, but no avail.
-                /* HasNUW */ OBO->hasNoUnsignedWrap() && IsSigned,
-                /* HasNSW */ IsSigned);
-
-            // Because both the multiplier and divisor are unsigned, we can use
-            // lshr
-            // TODO: revisit this if we let negative powers of 2
-            Instruction *Shift = BinaryOperator::CreateLShr(
-                Mul, ConstantInt::get(Ty, Q.logBase2()));
-            Shift->setIsExact(I.isExact());
-            return Shift;
+          APInt C4 = IsSigned ? C1->sdiv(C3) : C1->udiv(C3);
+          auto *Mul = Builder.CreateMul(
+              X, ConstantInt::get(Ty, C4), "",
+              // If it is unsigned, then we cannot have any nsw or nuw flags.
+              // It has been tried before, but no avail.
+              /* HasNUW */ OBO->hasNoUnsignedWrap() && IsSigned,
+              /* HasNSW */ IsSigned);
+
+          // Because both the multiplier and divisor are unsigned, we can use
+          // lshr
+          // TODO: revisit this if we let negative powers of 2
+          Instruction *Shift = BinaryOperator::CreateLShr(
+              Mul, ConstantInt::get(Ty, Q.logBase2()));
+          Shift->setIsExact(I.isExact());
+          return Shift;
         }
       }
     }

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https://github.com/llvm/llvm-project/pull/88220