[llvm] [PowerPC] extend smaller splats into bigger splats (with fix) (PR #142194)

[zhijian lin via llvm-commits]

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@@ -9664,7 +9664,24 @@ SDValue PPCTargetLowering::LowerBUILD_VECTOR(SDValue Op,
     }
   }
 
-  if (!BVNIsConstantSplat || SplatBitSize > 32) {
+  bool IsSplat64 = false;
+  uint64_t SplatBits = 0;
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diggerlin wrote:

nit: we can  put the `uint64_t SplatBits = 0;` inside the `if (BVNIsConstantSplat && SplatBitSize <= 64) {`

https://github.com/llvm/llvm-project/pull/142194