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

[Vikram Hegde via cfe-commits]

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@@ -278,7 +310,13 @@ static Value *callBufferedPrintfStart(
             StringData(StringRef(), LenWithNull, LenWithNullAligned, false));
       }
     } else {
-      int AllocSize = M->getDataLayout().getTypeAllocSize(Args[i]->getType());
+      int AllocSize = 0;
+      if (OCLVectors.test(i)) {
+        auto VecArg = dyn_cast<FixedVectorType>(Args[i]->getType());
+        assert(VecArg && "invalid vector specifier");
+        AllocSize = VecArg->getNumElements() * 8;
+      } else
+        AllocSize = M->getDataLayout().getTypeAllocSize(Args[i]->getType());
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vikramRH wrote:

I extract individual vector elements, expand them to 8 bytes and store them onto the buffer. The "getTypeAllocSize" would not give me the actual occupied size in the buffer in this case.

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