[llvm] InstSimplify: strip bad TODO (NFC) (PR #92754)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-analysis

Author: Ramkumar Ramachandra (artagnon)

<details>
<summary>Changes</summary>

foldIdentityShuffles() has a TODO comment about looking through bitcasts. Looking through any intervening instructions when folding shuffles is out-of-scope of InstructionSimplify, as the analysis is not allowed to modify the IR in any way. Strip this bad TODO.

---
Full diff: https://github.com/llvm/llvm-project/pull/92754.diff


1 Files Affected:

- (modified) llvm/lib/Analysis/InstructionSimplify.cpp (-3) 


``````````diff
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 37a7259a5cd02..e88736b5fab8d 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -5346,9 +5346,6 @@ static Value *foldIdentityShuffles(int DestElt, Value *Op0, Value *Op1,
         SourceShuf->getMaskValue(RootElt), RootVec, MaxRecurse);
   }
 
-  // TODO: Look through bitcasts? What if the bitcast changes the vector element
-  // size?
-
   // The source operand is not a shuffle. Initialize the root vector value for
   // this shuffle if that has not been done yet.
   if (!RootVec)

``````````

</details>


https://github.com/llvm/llvm-project/pull/92754