[Mlir-commits] [mlir] 914e72d - [mlir][linalg] Run CSE after every CodegenStrategy transformation.

[llvmlistbot at llvm.org]

Author: gysit
Date: 2021-11-30T15:07:51Z
New Revision: 914e72d40014de1c61709969666be59f27712e5e

URL: https://github.com/llvm/llvm-project/commit/914e72d40014de1c61709969666be59f27712e5e
DIFF: https://github.com/llvm/llvm-project/commit/914e72d40014de1c61709969666be59f27712e5e.diff

LOG: [mlir][linalg] Run CSE after every CodegenStrategy transformation.

Add CSE after every transformation. Transformations such as tiling introduce redundant computation, for example, one AffineMinOp for every operand dimension pair. Follow up transformations such as Padding and Hoisting benefit from CSE since comparing slice sizes simplifies to comparing SSA values instead of analyzing affine expressions.

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D114585

Added: 
    

Modified: 
    mlir/lib/Dialect/Linalg/Transforms/LinalgStrategyPasses.cpp
    mlir/test/Dialect/Linalg/codegen-strategy.mlir

Removed: 
    


################################################################################
diff  --git a/mlir/lib/Dialect/Linalg/Transforms/LinalgStrategyPasses.cpp b/mlir/lib/Dialect/Linalg/Transforms/LinalgStrategyPasses.cpp
index 8ed43c8b0dbae..8beeba759cd02 100644
--- a/mlir/lib/Dialect/Linalg/Transforms/LinalgStrategyPasses.cpp
+++ b/mlir/lib/Dialect/Linalg/Transforms/LinalgStrategyPasses.cpp
@@ -25,9 +25,11 @@
 #include "mlir/Dialect/Vector/VectorTransforms.h"
 #include "mlir/IR/AffineExpr.h"
 #include "mlir/IR/AffineMap.h"
+#include "mlir/Pass/PassManager.h"
 #include "mlir/Support/LLVM.h"
 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
 #include "mlir/Transforms/LoopUtils.h"
+#include "mlir/Transforms/Passes.h"
 #include "mlir/Transforms/Utils.h"
 
 using namespace mlir;
@@ -335,6 +337,12 @@ struct LinalgStrategyEnablePass
 
     if (options.hoistRedundantVectorTransfersOnTensor)
       hoistRedundantVectorTransfersOnTensor(funcOp);
+
+    // Run CSE to cleanup after canonicalization.
+    OpPassManager dynamicPM("builtin.func");
+    dynamicPM.addPass(createCSEPass());
+    if (failed(runPipeline(dynamicPM, funcOp)))
+      return signalPassFailure();
   }
 
   LinalgEnablingOptions options;

diff  --git a/mlir/test/Dialect/Linalg/codegen-strategy.mlir b/mlir/test/Dialect/Linalg/codegen-strategy.mlir
index fc65a593fc4ed..d1deffafaf937 100644
--- a/mlir/test/Dialect/Linalg/codegen-strategy.mlir
+++ b/mlir/test/Dialect/Linalg/codegen-strategy.mlir
@@ -40,14 +40,19 @@ func @matmul(%arg0: tensor<72x72xf32>, %arg1: tensor<72x72xf32>, %arg2: tensor<7
 
 // -----
 
+//     CHECK-PAD-DAG: #[[MAP0:[0-9a-z]+]] = affine_map<(d0) -> (16, -d0 + 72)>
+
 //         CHECK-PAD: func @matmul(
 func @matmul(%arg0: tensor<72x72xf32>, %arg1: tensor<72x72xf32>, %arg2: tensor<72x72xf32>) -> tensor<72x72xf32> {
 
   // Check the padding of the input operands has been hoisted out of the tile loop nest.
   //      CHECK-PAD-COUNT=2: linalg.pad_tensor %{{.*}} nofold
-  //      CHECK-PAD-COUNT=3: scf.for
+  //              CHECK-PAD: scf.for
+  // Check CSE eliminates the duplicate min operations introduced by tiling.
+  //              CHECK-PAD: affine.min #[[MAP0]]
+  //          CHECK-PAD-NOT: affine.min #[[MAP0]]
+  //      CHECK-PAD-COUNT=2: scf.for
   //              CHECK-PAD: linalg.matmul
   %0 = linalg.matmul ins(%arg0, %arg1: tensor<72x72xf32>, tensor<72x72xf32>) outs(%arg2: tensor<72x72xf32>) -> tensor<72x72xf32>
   return %0 : tensor<72x72xf32>
 }
-