[flang-commits] [flang] [flang] disable cf canonicalization patterns at O0 to preserve line location (PR #227770)

[Abid Qadeer via flang-commits]

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@@ -0,0 +1,59 @@
+//===-- O0CanonicalizerPass.cpp -- Canonicalization for O0 ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "flang/Optimizer/Transforms/Passes.h"
+#include "mlir/Dialect/ControlFlow/IR/ControlFlow.h"
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+
+namespace fir {
+#define GEN_PASS_DEF_O0CANONICALIZERPASS
+#include "flang/Optimizer/Transforms/Passes.h.inc"
+} // namespace fir
+
+void fir::populateCanonicalizationPatterns(
+    mlir::RewritePatternSet &patterns, bool includeCFPatterns,
+    llvm::function_ref<bool(mlir::RegisteredOperationName)> shouldCollect) {
+  mlir::MLIRContext *context = patterns.getContext();
+  auto includeDialect = [&](mlir::Dialect *dialect) {
+    return includeCFPatterns ||
+           !mlir::isa<mlir::cf::ControlFlowDialect>(dialect);
+  };
+  for (mlir::Dialect *dialect : context->getLoadedDialects())
+    if (includeDialect(dialect))
+      dialect->getCanonicalizationPatterns(patterns);
+  for (mlir::RegisteredOperationName op : context->getRegisteredOperations())
+    if (includeDialect(&op.getDialect()) &&
+        (!shouldCollect || shouldCollect(op)))
+      op.getCanonicalizationPatterns(patterns, context);
+}
----------------
abidh wrote:

nit: The function mirrors some logic from Canonicalizer::initialize and a small comment may help a future reader.

https://github.com/llvm/llvm-project/pull/227770