[llvm] [InstCombine] Added optimization for shift add (PR #163502)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


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

<details>
<summary>
You can test this locally with the following command:
</summary>

``````````bash
git-clang-format --diff origin/main HEAD --extensions cpp -- llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp --diff_from_common_commit
``````````

:warning:
The reproduction instructions above might return results for more than one PR
in a stack if you are using a stacked PR workflow. You can limit the results by
changing `origin/main` to the base branch/commit you want to compare against.
:warning:

</details>

<details>
<summary>
View the diff from clang-format here.
</summary>

``````````diff
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
index 85326bd5b..c81dad951 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
@@ -632,7 +632,8 @@ static bool canEvaluateShifted(Value *V, unsigned NumBits, bool IsLeftShift,
       return false;
 
     // Both operands must be shiftable, pass through CxtI to preserve shift type
-    return canEvaluateShifted(I->getOperand(0), NumBits, IsLeftShift, IC, CxtI) &&
+    return canEvaluateShifted(I->getOperand(0), NumBits, IsLeftShift, IC,
+                              CxtI) &&
            canEvaluateShifted(I->getOperand(1), NumBits, IsLeftShift, IC, CxtI);
   }
 
@@ -1679,8 +1680,8 @@ Instruction *InstCombinerImpl::visitLShr(BinaryOperator &I) {
   // when the shift is exact and the add has nuw.
   const APInt *ShAmtAPInt, *ShlAmt, *AddC;
   if (match(Op1, m_APInt(ShAmtAPInt)) && I.isExact() &&
-      match(Op0, m_c_NUWAdd(m_NUWShl(m_Value(X), m_APInt(ShlAmt)),
-                            m_APInt(AddC))) &&
+      match(Op0,
+            m_c_NUWAdd(m_NUWShl(m_Value(X), m_APInt(ShlAmt)), m_APInt(AddC))) &&
       ShlAmt->uge(*ShAmtAPInt)) {
     unsigned ShAmt = ShAmtAPInt->getZExtValue();
     // Check if C is divisible by (1 << ShAmt)

``````````

</details>


https://github.com/llvm/llvm-project/pull/163502