[clang] [clang][SPIRV] Add builtin for OpGenericCastToPtrExplicit and its SPIR-V friendly binding (PR #137805)

[Farzon Lotfi via cfe-commits]

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@@ -35,8 +35,10 @@ static constexpr Builtin::Info BuiltinInfos[] = {
 static_assert(std::size(BuiltinInfos) == NumBuiltins);
 
 llvm::SmallVector<Builtin::InfosShard>
-SPIRVTargetInfo::getTargetBuiltins() const {
-  return {{&BuiltinStrings, BuiltinInfos}};
+BaseSPIRTargetInfo::getTargetBuiltins() const {
+  if (getTriple().isSPIRV())
+    return {{&BuiltinStrings, BuiltinInfos}};
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farzonl wrote:

I don't understand why this change (in SPIR.cpp and SPIR.h) is necessesary.  The existing code accomplished the same thing with method overriding. The original code also had some defensive programming safety to me. We went  from a compile time enforcement of  SPIRVTargetInfo== BuiltinsSPIRV.td to now a runtime enforcement. The problem with that is the next guy that comes along and makes a change might assume the builtins so far are SPIRV and thats why you are checking the triple, then add a new SPIR flavor builtin that would not be valid for SPIRV.

https://github.com/llvm/llvm-project/pull/137805