[Mlir-commits] [mlir] [mlir][spirv] Add gpu printf op lowering to spirv.CL.printf op (PR #78510)

[Jakub Kuderski]

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@@ -607,6 +616,108 @@ class GPUSubgroupReduceConversion final
   }
 };
 
+LogicalResult GPUPrintfConversion::matchAndRewrite(
+    gpu::PrintfOp gpuPrintfOp, OpAdaptor adaptor,
+    ConversionPatternRewriter &rewriter) const {
+
+  auto loc = gpuPrintfOp.getLoc();
+
+  auto funcOp =
+      rewriter.getBlock()->getParent()->getParentOfType<mlir::spirv::FuncOp>();
+
+  auto moduleOp = funcOp->getParentOfType<mlir::spirv::ModuleOp>();
+
+  const char formatStringPrefix[] = "printfMsg";
+  unsigned stringNumber = 0;
+  mlir::SmallString<16> globalVarName;
+  mlir::spirv::GlobalVariableOp globalVar;
+
+  // formulate spirv global variable name
+  do {
+    globalVarName.clear();
+    (formatStringPrefix + llvm::Twine(stringNumber++))
+        .toStringRef(globalVarName);
+  } while (moduleOp.lookupSymbol(globalVarName));
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kuhar wrote:

I don't understand what this is trying to do. Can we simplify this and/or add some comment with an example?

https://github.com/llvm/llvm-project/pull/78510