[llvm] [AMDGPU] Replace `isInlinableLiteral16` with specific version (PR #84402)

[Shilei Tian via llvm-commits]

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@@ -3327,35 +3327,41 @@ bool AMDGPUDAGToDAGISel::SelectWMMAVISrc(SDValue In, SDValue &Src) const {
 
   // 16 bit splat
   SDValue SplatSrc32 = stripBitcast(In);
-  if (auto *SplatSrc32BV = dyn_cast<BuildVectorSDNode>(SplatSrc32)) {
+  if (auto *SplatSrc32BV = dyn_cast<BuildVectorSDNode>(SplatSrc32))
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shiltian wrote:

For some reason this trunk of code was missing in the previous version. That caused the two WMMA instructions to be generated incorrectly. Good catch!

https://github.com/llvm/llvm-project/pull/84402