[flang-commits] [clang] [flang] [flang][OpenMP] Add -f[no]-openmp-simd (PR #150269)

[Tom Eccles via flang-commits]

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@@ -0,0 +1,360 @@
+#include "flang/Optimizer/Builder/FIRBuilder.h"
+#include "flang/Optimizer/Transforms/Utils.h"
+#include "mlir/Dialect/ControlFlow/IR/ControlFlowOps.h"
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/OpenMP/OpenMPDialect.h"
+#include "mlir/IR/IRMapping.h"
+#include "mlir/Pass/Pass.h"
+#include "mlir/Transforms/DialectConversion.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+#include <llvm/Support/Debug.h>
+#include <mlir/IR/MLIRContext.h>
+#include <mlir/IR/Operation.h>
+#include <mlir/IR/PatternMatch.h>
+#include <mlir/Support/LLVM.h>
+
+namespace flangomp {
+#define GEN_PASS_DEF_SIMDONLYPASS
+#include "flang/Optimizer/OpenMP/Passes.h.inc"
+} // namespace flangomp
+
+namespace {
+
+#define DEBUG_TYPE "omp-simd-only-pass"
+
+class SimdOnlyConversionPattern : public mlir::RewritePattern {
+public:
+  SimdOnlyConversionPattern(mlir::MLIRContext *ctx)
+      : mlir::RewritePattern(MatchAnyOpTypeTag{}, 1, ctx) {}
+
+  mlir::LogicalResult
+  matchAndRewrite(mlir::Operation *op,
+                  mlir::PatternRewriter &rewriter) const override {
+    if (op->getDialect()->getNamespace() !=
+        mlir::omp::OpenMPDialect::getDialectNamespace())
+      return rewriter.notifyMatchFailure(op, "Not an OpenMP op");
+
+    if (auto simdOp = mlir::dyn_cast<mlir::omp::SimdOp>(op)) {
+      // Remove the composite attr given that the op will no longer be composite
+      if (simdOp.isComposite()) {
+        simdOp.setComposite(false);
+        return mlir::success();
+      }
+
+      return rewriter.notifyMatchFailure(op, "Op is a plain SimdOp");
+    }
+
+    if (op->getParentOfType<mlir::omp::SimdOp>())
+      return rewriter.notifyMatchFailure(op, "Op is nested under a SimdOp");
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tblah wrote:

I imagine this won't happen much in practice, but why are we not rewriting things inside of simd? Is this to avoid converting the loop wrapper?

https://github.com/llvm/llvm-project/pull/150269