[clang] [llvm] [msan] Implement support for Arm NEON vst{2,3,4} instructions (PR #99360)

[Vitaly Buka via cfe-commits]

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@@ -2483,13 +2484,21 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
   using OriginCombiner = Combiner<false>;
 
   /// Propagate origin for arbitrary operation.
-  void setOriginForNaryOp(Instruction &I) {
+  ///
+  /// Optionally skips n trailing operands.
+  void setOriginForNaryOp(Instruction &I, unsigned int skipLastOperands = 0) {
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vitalybuka wrote:

for this particular case skipping callee is unnecessary, it will be skipped in .Add()
as `getShadow` for that operand should be null.


https://github.com/llvm/llvm-project/pull/99360