[clang] [clang][SPIR-V] Add x86 calling conventions and sse/sse2 for MSVC hosts (PR #227665)

[via cfe-commits]

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@@ -15,6 +15,10 @@ void bar() {
   printf("hello\n");
 }
 
+// Accepted by the SPIR-V target itself, with no host to fall back on.
+void __attribute__((regcall)) rcall(int a, int b) {}
+void __attribute__((vectorcall)) vcall(float a, float b) {}
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schittir wrote:

Agreed.

https://github.com/llvm/llvm-project/pull/227665