[clang][OpenMP][SPIR-V] Fix addrspace of global constants (llvm#134399)

SPIR-V has strict address space rules, constant globals cannot be in the
default address space.

The OMPIRBuilder change was required for lit tests to pass, we were
missing an addrspacecast.

---------

Signed-off-by: Sarnie, Nick <[email protected]>

Author: sarnex

clang/lib/Basic/Targets/SPIR.h

@@ -374,6 +374,20 @@ class LLVM_LIBRARY_VISIBILITY SPIRV64TargetInfo : public BaseSPIRVTargetInfo {
   const llvm::omp::GV &getGridValue() const override {
     return llvm::omp::SPIRVGridValues;
   }
+
+  std::optional<LangAS> getConstantAddressSpace() const override {
+    return ConstantAS;
+  }
+  void adjust(DiagnosticsEngine &Diags, LangOptions &Opts) override {
+    BaseSPIRVTargetInfo::adjust(Diags, Opts);
+    // opencl_constant will map to UniformConstant in SPIR-V
+    if (Opts.OpenCL)
+      ConstantAS = LangAS::opencl_constant;
+  }
+
+private:
+  // opencl_global will map to CrossWorkgroup in SPIR-V
+  LangAS ConstantAS = LangAS::opencl_global;
 };
 
 class LLVM_LIBRARY_VISIBILITY SPIRV64AMDGCNTargetInfo final

llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp

@@ -6360,6 +6360,12 @@ OpenMPIRBuilder::InsertPointTy OpenMPIRBuilder::createTargetInit(
           : ConstantExpr::getAddrSpaceCast(KernelEnvironmentGV,
                                            KernelEnvironmentPtr);
   Value *KernelLaunchEnvironment = DebugKernelWrapper->getArg(0);
+  Type *KernelLaunchEnvParamTy = Fn->getFunctionType()->getParamType(1);
+  KernelLaunchEnvironment =
+      KernelLaunchEnvironment->getType() == KernelLaunchEnvParamTy
+          ? KernelLaunchEnvironment
+          : Builder.CreateAddrSpaceCast(KernelLaunchEnvironment,
+                                        KernelLaunchEnvParamTy);
   CallInst *ThreadKind =
       Builder.CreateCall(Fn, {KernelEnvironment, KernelLaunchEnvironment});