llvm.x86.sse.pshuf.w(<1 x i64>, i8) and llvm.x86.avx512.pshuf.b.512(<64
x i8>, <64 x i8>) are currently handled strictly, which is suboptimal.
llvm.x86.ssse3.pshuf.b(<1 x i64>, <1 x i64>)
llvm.x86.ssse3.pshuf.b.128(<16 x i8>, <16 x i8>) and
llvm.x86.avx2.pshuf.b(<32 x i8>, <32 x i8>) are currently heuristically
handled using maybeHandleSimpleNomemIntrinsic, which is incorrect.
Since the second argument is the shuffle order, we instrument all these
intrinsics using `handleIntrinsicByApplyingToShadow(...,
/*trailingVerbatimArgs=*/1)`
(https://github.com/llvm/llvm-project/pull/114490).
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