[compiler-rt] [llvm] [msan] Add 32-bit platforms support (PR #109284)

[via llvm-commits]

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@@ -6004,8 +6026,122 @@ struct VarArgSystemZHelper : public VarArgHelperBase {
   }
 };
 
-/// MIPS-specific implementation of VarArgHelper.
-/// NOTE: This is also used for LoongArch64.
+/// i386-specific implementation of VarArgHelper.
+struct VarArgI386Helper : public VarArgHelperBase {
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k-kashapov wrote:

If I remember correctly, this has been copied from GenericHelper. Then `visitCallBase` has been modified to differentiate "by val" parameter passing.

https://github.com/llvm/llvm-project/pull/109284