[clang] [llvm] [AMDGPU] Enable OpenCL hostcall printf (WIP) (PR #72556)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -198,15 +213,31 @@ RValue CodeGenFunction::EmitAMDGPUDevicePrintfCallExpr(const CallExpr *E) {
     }
 
     llvm::Value *Arg = A.getRValue(*this).getScalarVal();
+    if (isString(A.getType().getTypePtr()) && CGM.getLangOpts().OpenCL)
+      Arg = Builder.CreateAddrSpaceCast(Arg, CGM.Int8PtrTy);
     Args.push_back(Arg);
   }
 
-  llvm::IRBuilder<> IRB(Builder.GetInsertBlock(), Builder.GetInsertPoint());
-  IRB.SetCurrentDebugLocation(Builder.getCurrentDebugLocation());
+  auto PFK = CGM.getTarget().getTargetOpts().AMDGPUPrintfKindVal;
+  bool isBuffered =
+       (PFK == clang::TargetOptions::AMDGPUPrintfKind::Buffered);
+
+  StringRef FmtStr;
+  if (llvm::getConstantStringInfo(Args[0], FmtStr)) {
+    if (FmtStr.empty())
+      FmtStr = StringRef("", 1);
+  } else {
+    if (CGM.getLangOpts().OpenCL) {
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ssahasra wrote:

This looks like the wrong place for a diagnostic. For an OpenCL program, shouldn't Sema have already verified that the arguments match the required types, such as "constant address space" for the format string?

https://github.com/llvm/llvm-project/pull/72556