[clang] [llvm] [clang][OpenMP][SPIR-V] Fix AS of globals and set the default AS to 4 (PR #135251)

[Nick Sarnie via cfe-commits]

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@@ -1217,11 +1217,13 @@ void CGOpenMPRuntimeGPU::emitParallelCall(CodeGenFunction &CGF,
     CGBuilderTy &Bld = CGF.Builder;
     llvm::Value *NumThreadsVal = NumThreads;
     llvm::Function *WFn = WrapperFunctionsMap[OutlinedFn];
+    llvm::FunctionCallee RuntimeFn = OMPBuilder.getOrCreateRuntimeFunction(
+        CGM.getModule(), OMPRTL___kmpc_parallel_51);
     llvm::Value *ID = llvm::ConstantPointerNull::get(CGM.Int8PtrTy);
     if (WFn)
       ID = Bld.CreateBitOrPointerCast(WFn, CGM.Int8PtrTy);
-    llvm::Value *FnPtr = Bld.CreateBitOrPointerCast(OutlinedFn, CGM.Int8PtrTy);
-
+    llvm::Value *FnPtr = Bld.CreateAddrSpaceCast(OutlinedFn, CGM.Int8PtrTy);
+    FnPtr = Bld.CreateBitOrPointerCast(FnPtr, CGM.Int8PtrTy);
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sarnex wrote:

Yeah this one is annoying, so we are trying to cast a fcn ptr to int8 ptr (both just opaque now as you said), but the int8 ptr type is addrspace 4, and the function is addrspace 0, so we can't cast the function to the ptr in a single cast because we need to deal with the addrspace

https://github.com/llvm/llvm-project/pull/135251