[llvm] [InstCombine] lshr (mul (X, 2^N + 1)), N -> add (X, lshr(X, N)) (PR #90295)

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``````````bash
git-clang-format --diff b6a8f5486bc12b132ec984bc8767506e3bcb6694 497f793e72c09e370670de36aa96eacb5e29e840 -- llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
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View the diff from clang-format here.
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diff --git a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
index ccfef8cf93..a4ea4b2e60 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
@@ -1411,7 +1411,8 @@ Instruction *InstCombinerImpl::visitLShr(BinaryOperator &I) {
 
     const APInt *MulC;
     if (match(Op0, m_NUWMul(m_Value(X), m_APInt(MulC)))) {
-      if (BitWidth > 2 && (*MulC - 1).isPowerOf2() && MulC->logBase2() == ShAmtC) {
+      if (BitWidth > 2 && (*MulC - 1).isPowerOf2() &&
+          MulC->logBase2() == ShAmtC) {
         // Look for a "splat" mul pattern - it replicates bits across each half
         // of a value, so a right shift is just a mask of the low bits:
         // lshr i[2N] (mul nuw X, (2^N)+1), N --> and iN X, (2^N)-1

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https://github.com/llvm/llvm-project/pull/90295