commit b843cc5d5af10e35081751866d4fc216a0b5e5e4
author Stephan Herhut <herhut@google.com> Wed Oct 16 04:28:13 2019 -0700
committer A. Unique TensorFlower <gardener@tensorflow.org> Wed Oct 16 04:28:38 2019 -0700
tree 6d23fc79d0eb7ac88ad3036bdd5bf0cac8eada3d
parent 98f64b4da1afb7ca2c96de75d5c9cbe628ce3976

Implement simple loop-invariant-code-motion based on dialect interfaces.

PiperOrigin-RevId: 275004258

mlir/lib/Dialect/LoopOps/LoopOps.cpp

diff --git a/mlir/lib/Dialect/LoopOps/LoopOps.cpp b/mlir/lib/Dialect/LoopOps/LoopOps.cpp
index 7ea9c15..1dc7deb 100644
--- a/mlir/lib/Dialect/LoopOps/LoopOps.cpp
+++ b/mlir/lib/Dialect/LoopOps/LoopOps.cpp
@@ -29,11 +29,30 @@
 #include "mlir/IR/Value.h"
 #include "mlir/Support/MathExtras.h"
 #include "mlir/Support/STLExtras.h"
+#include "mlir/Transforms/SideEffectsInterface.h"
 
 using namespace mlir;
 using namespace mlir::loop;
 
 //===----------------------------------------------------------------------===//
+// LoopOpsDialect Interfaces
+//===----------------------------------------------------------------------===//
+namespace {
+
+struct LoopSideEffectsInterface : public SideEffectsDialectInterface {
+  using SideEffectsDialectInterface::SideEffectsDialectInterface;
+
+  SideEffecting isSideEffecting(Operation *op) const override {
+    if (isa<IfOp>(op) || isa<ForOp>(op)) {
+      return Recursive;
+    }
+    return SideEffectsDialectInterface::isSideEffecting(op);
+  };
+};
+
+} // namespace
+
+//===----------------------------------------------------------------------===//
 // LoopOpsDialect
 //===----------------------------------------------------------------------===//
 
@@ -43,6 +62,7 @@
 #define GET_OP_LIST
 #include "mlir/Dialect/LoopOps/LoopOps.cpp.inc"
       >();
+  addInterfaces<LoopSideEffectsInterface>();
 }
 
 //===----------------------------------------------------------------------===//
@@ -112,6 +132,18 @@
   return success();
 }
 
+Region &ForOp::getLoopBody() { return region(); }
+
+bool ForOp::isDefinedOutsideOfLoop(Value *value) {
+  return !region().isAncestor(value->getParentRegion());
+}
+
+LogicalResult ForOp::moveOutOfLoop(ArrayRef<Operation *> ops) {
+  for (auto *op : ops)
+    op->moveBefore(this->getOperation());
+  return success();
+}
+
 ForOp mlir::loop::getForInductionVarOwner(Value *val) {
   auto *ivArg = dyn_cast<BlockArgument>(val);
   if (!ivArg)