mlir/test/Transforms/parametric-tiling.mlir

// RUN: mlir-opt -test-extract-fixed-outer-loops='test-outer-loop-sizes=7' %s | FileCheck %s --check-prefixes=COMMON,TILE_7
// RUN: mlir-opt -test-extract-fixed-outer-loops='test-outer-loop-sizes=7,4' %s | FileCheck %s --check-prefixes=COMMON,TILE_74

// COMMON-LABEL: @rectangular
func.func @rectangular(%arg0: memref<?x?xf32>) {
  %c2 = arith.constant 2 : index
  %c44 = arith.constant 44 : index
  %c1 = arith.constant 1 : index
  // Range of the original loop:
  //   (upper - lower + step - 1) / step
  // where step is known to be %c1.
  // COMMON:      %[[diff:.*]] = arith.subi %c44, %c2
  // COMMON:      %[[adjustment:.*]] = arith.subi %c1, %c1_{{.*}}
  // COMMON-NEXT: %[[diff_adj:.*]] = arith.addi %[[diff]], %[[adjustment]]
  // COMMON-NEXT: %[[range:.*]] = arith.divui %[[diff_adj]], %c1

  // Ceildiv to get the parametric tile size.
  // COMMON:       %[[sum:.*]] = arith.addi %[[range]], %c6
  // COMMON-NEXT:  %[[size:.*]] = arith.divui %[[sum]], %c7
  // New outer step (original is %c1).
  // COMMON-NEXT:      %[[step:.*]] = arith.muli %c1, %[[size]]

  // Range of the second original loop
  //   (upper - lower + step - 1) / step
  // where step is known to be %c2.
  // TILE_74:      %[[diff2:.*]] = arith.subi %c44, %c1
  // TILE_74:      %[[adjustment2:.*]] = arith.subi %c2, %c1_{{.*}}
  // TILE_74-NEXT: %[[diff2_adj:.*]] = arith.addi %[[diff2]], %[[adjustment2]]
  // TILE_74-NEXT: %[[range2:.*]] = arith.divui %[[diff2_adj]], %c2

  // Ceildiv to get the parametric tile size for the second original scf.
  // TILE_74:      %[[sum2:.*]] = arith.addi %[[range2]], %c3
  // TILE_74-NEXT: %[[size2:.*]] = arith.divui %[[sum2]], %c4
  // New inner step (original is %c2).
  // TILE_74-NEXT:     %[[step2:.*]] = arith.muli %c2, %[[size2]]

  // Updated outer loop(s) use new steps.
  // COMMON: scf.for %[[i:.*]] = %c2 to %c44 step %[[step]]
  // TILE_74:scf.for %[[j:.*]] = %c1 to %c44 step %[[step2]]
 scf.for %i = %c2 to %c44 step %c1 {
    // Upper bound for the inner loop min(%i + %step, %c44).
    // COMMON:      %[[stepped:.*]] = arith.addi %[[i]], %[[step]]
    // COMMON-NEXT: %[[ub:.*]] = arith.minsi %c44, %[[stepped]]
    //
    // TILE_74:      %[[stepped2:.*]] = arith.addi %[[j]], %[[step2]]
    // TILE_74-NEXT: %[[ub2:.*]] = arith.minsi %c44, %[[stepped2]]

    // Created inner scf.
    // COMMON:scf.for %[[ii:.*]] = %[[i]] to %[[ub:.*]] step %c1

    // This loop is not modified in TILE_7 case.
    // TILE_7: scf.for %[[j:.*]] = %c1 to %c44 step %c2
    //
    // But is modified in TILE_74 case.
    // TILE_74:scf.for %[[jj:.*]] = %[[j]] to %[[ub2]] step %c2
   scf.for %j = %c1 to %c44 step %c2 {
      // The right iterator are used.
      // TILE_7:  memref.load %arg0[%[[ii]], %[[j]]]
      // TILE_74: memref.load %arg0[%[[ii]], %[[jj]]]
      memref.load %arg0[%i, %j]: memref<?x?xf32>
    }
  }
  return
}

// COMMON-LABEL: @triangular
func.func @triangular(%arg0: memref<?x?xf32>) {
  %c2 = arith.constant 2 : index
  %c44 = arith.constant 44 : index
  %c1 = arith.constant 1 : index
  // Range of the original outer loop:
  //   (upper - lower + step - 1) / step
  // where step is known to be %c1.
  // COMMON:      %[[diff:.*]] = arith.subi %c44, %c2
  // COMMON:      %[[adjustment:.*]] = arith.subi %c1, %c1_{{.*}}
  // COMMON-NEXT: %[[diff_adj:.*]] = arith.addi %[[diff]], %[[adjustment]]
  // COMMON-NEXT: %[[range:.*]] = arith.divui %[[diff_adj]], %c1

  // Ceildiv to get the parametric tile size.
  // COMMON:       %[[sum:.*]] = arith.addi %[[range]], %c6
  // COMMON-NEXT:  %[[size:.*]] = arith.divui %[[sum]], %c7
  // New outer step (original is %c1).
  // COMMON-NEXT:  %[[step:.*]] = arith.muli %c1, %[[size]]

  // Constant adjustment for inner loop has been hoisted out.
  // TILE_74:      %[[adjustment2:.*]] = arith.subi %c2, %c1_{{.*}}

  // New outer scf.
  // COMMON: scf.for %[[i:.*]] = %c2 to %c44 step %[[step]]

  // Range of the original inner loop
  //   (upper - lower + step - 1) / step
  // where step is known to be %c2.
  // TILE_74:      %[[diff2:.*]] = arith.subi %[[i]], %c1
  // TILE_74-NEXT: %[[diff2_adj:.*]] = arith.addi %[[diff2]], %[[adjustment2]]
  // TILE_74-NEXT: %[[range2:.*]] = arith.divui %[[diff2_adj]], %c2

  // Ceildiv to get the parametric tile size for the second original scf.
  // TILE_74:      %[[sum2:.*]] = arith.addi %[[range2]], %c3
  // TILE_74-NEXT: %[[size2:.*]] = arith.divui %[[sum2]], %c4
  // New inner step (original is %c2).
  // TILE_74-NEXT:     %[[step2:.*]] = arith.muli %c2, %[[size2]]

  // New inner scf.
  // TILE_74:scf.for %[[j:.*]] = %c1 to %[[i]] step %[[step2]]
 scf.for %i = %c2 to %c44 step %c1 {
    // Upper bound for the inner loop min(%i + %step, %c44).
    // COMMON:      %[[stepped:.*]] = arith.addi %[[i]], %[[step]]
    // COMMON-NEXT: %[[ub:.*]] = arith.minsi %c44, %[[stepped]]
    // TILE_74:      %[[stepped2:.*]] = arith.addi %[[j]], %[[step2]]
    // TILE_74-NEXT: %[[ub2:.*]] = arith.minsi %[[i]], %[[stepped2]]
    //
    // Created inner scf.
    // COMMON:scf.for %[[ii:.*]] = %[[i]] to %[[ub:.*]] step %c1

    // This loop is not modified in TILE_7 case.
    // TILE_7: scf.for %[[j:.*]] = %c1 to %[[ii]] step %c2
    //
    // But is modified in TILE_74 case.
    // TILE_74:scf.for %[[jj:.*]] = %[[j]] to %[[ub2]] step %c2
   scf.for %j = %c1 to %i step %c2 {
      // The right iterator are used.
      // TILE_7:  memref.load %arg0[%[[ii]], %[[j]]]
      // TILE_74: memref.load %arg0[%[[ii]], %[[jj]]]
      memref.load %arg0[%i, %j]: memref<?x?xf32>
    }
  }
  return
}

// Verify that extractFixedOuterLoops silently skips loops with iter_args
// instead of producing invalid IR (regression test for
// https://github.com/llvm/llvm-project/issues/129044).

// COMMON-LABEL: @loop_with_iter_args
// COMMON: scf.for {{.*}} iter_args({{.*}}) -> (f32)
func.func @loop_with_iter_args(%buffer: memref<1024xf32>, %lb: index,
                               %ub: index, %step: index) -> f32 {
  %initial_sum = arith.constant 0.0 : f32
  // This loop has iter_args; strip-mining must not be applied.
  %final_sum = scf.for %iv = %lb to %ub step %step
      iter_args(%sum_iter = %initial_sum) -> (f32) {
    %element = memref.load %buffer[%iv] : memref<1024xf32>
    %updated_sum = arith.addf %sum_iter, %element : f32
    scf.yield %updated_sum : f32
  }
  return %final_sum : f32
}