[llvm] [LoongArch] Refine 256-bit vector_shuffle legalization for LASX (PR #160254)

[via llvm-commits]

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@@ -2354,7 +2357,7 @@ static SDValue lowerVECTOR_SHUFFLE_XVSHUF(const SDLoc &DL, ArrayRef<int> Mask,
 /// cases need to be converted to it for processing.
 ///
 /// This function may modify V1, V2 and Mask
-static void canonicalizeShuffleVectorByLane(
+static bool canonicalizeShuffleVectorByLane(
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heiher wrote:

Could you add more code comments about the return value?

https://github.com/llvm/llvm-project/pull/160254