maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[MLIR] Fix incorrect removal of source loop in loop fusion 

This patch fixes a bug in loop fusion pass where the source loop was removed
even when the fused loop did not cover all iterations of the source loop.

This was because the fast hueristic check for checking if source loop and
fused loop have same iterations did not take into account steps in loop.

Reviewed By: dcaballe, bondhugula

Differential Revision: https://reviews.llvm.org/D114164
This commit is contained in:
Groverkss 2021-11-23 02:48:03 +05:30
parent 2975f37d8d
commit 98daa4e425
2 changed files with 34 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
mlir/lib/Analysis/Utils.cpp
View File

@ -207,7 +207,8 @@ Optional<bool> ComputationSliceState::isSliceMaximalFastCheck() const {
// Check if src and dst loop bounds are the same. If not, we can guarantee
// that the slice is not maximal.
if (srcLbResult != dstLbResult || srcUbResult != dstUbResult)
if (srcLbResult != dstLbResult || srcUbResult != dstUbResult ||
srcLoop.getStep() != dstLoop.getStep())
return false;
}

32
mlir/test/Transforms/loop-fusion-4.mlir
View File

@ -71,6 +71,38 @@ func @unflatten2d_with_transpose(%arg1: memref<8x7xf32>) {
// -----
// Expects fusion of producer into consumer at depth 1 and source loop to not
// be removed due to difference in loop steps.
// PRODUCER-CONSUMER-LABEL: func @check_src_dst_step
func @check_src_dst_step(%m : memref<100xf32>,
%src: memref<100xf32>,
%out: memref<100xf32>) {
affine.for %i0 = 0 to 100 {
%r1 = affine.load %src[%i0]: memref<100xf32>
affine.store %r1, %m[%i0] : memref<100xf32>
}
affine.for %i2 = 0 to 100 step 2 {
%r2 = affine.load %m[%i2] : memref<100xf32>
affine.store %r2, %out[%i2] : memref<100xf32>
}
return
}
// Check if the fusion did take place as well as that the source loop was
// not removed. To check if fusion took place, the read instruction from the
// original source loop is checked to be in the fused loop.
//
// PRODUCER-CONSUMER: affine.for %[[idx_0:.*]] = 0 to 100 {
// PRODUCER-CONSUMER-NEXT: %[[result_0:.*]] = affine.load %[[arr1:.*]][%[[idx_0]]] : memref<100xf32>
// PRODUCER-CONSUMER-NEXT: affine.store %[[result_0]], %{{.*}}[%[[idx_0]]] : memref<100xf32>
// PRODUCER-CONSUMER-NEXT: }
// PRODUCER-CONSUMER: affine.for %[[idx_1:.*]] = 0 to 100 step 2 {
// PRODUCER-CONSUMER: affine.load %[[arr1]][%[[idx_1]]] : memref<100xf32>
// PRODUCER-CONSUMER: }
// PRODUCER-CONSUMER: return
// -----
// SIBLING-MAXIMAL-LABEL: func @reduce_add_non_maximal_f32_f32(
func @reduce_add_non_maximal_f32_f32(%arg0: memref<64x64xf32, 1>, %arg1 : memref<1x64xf32, 1>, %arg2 : memref<1x64xf32, 1>) {
%cst_0 = arith.constant 0.000000e+00 : f32