[Mlir-commits] [mlir] [mlir] Speed up FuncToLLVM using a SymbolTable (PR #68082)

[Oleksandr Alex Zinenko]

================
@@ -601,19 +603,38 @@ struct CallOpInterfaceLowering : public ConvertOpToLLVMPattern<CallOpType> {
   }
 };
 
-struct CallOpLowering : public CallOpInterfaceLowering<func::CallOp> {
-  using Super::Super;
+class CallOpLowering : public CallOpInterfaceLowering<func::CallOp> {
+public:
+  CallOpLowering(const LLVMTypeConverter &typeConverter,
+                 // Can be nullptr.
+                 const SymbolTable *symbolTable, PatternBenefit benefit = 1)
+      : CallOpInterfaceLowering<func::CallOp>(typeConverter, benefit),
+        symbolTable(symbolTable) {}
 
   LogicalResult
   matchAndRewrite(func::CallOp callOp, OpAdaptor adaptor,
                   ConversionPatternRewriter &rewriter) const override {
     bool useBarePtrCallConv = false;
-    if (Operation *callee = SymbolTable::lookupNearestSymbolFrom(
-            callOp, callOp.getCalleeAttr())) {
-      useBarePtrCallConv = shouldUseBarePtrCallConv(callee, getTypeConverter());
+    if (getTypeConverter()->getOptions().useBarePtrCallConv) {
+      useBarePtrCallConv = true;
+    } else if (symbolTable != nullptr) {
+      // Fast hashmap lookup.
----------------
ftynse wrote:

```suggestion
      // Fast lookup.
```

https://github.com/llvm/llvm-project/pull/68082