[mlir] Expose region utils functions

As discussed in D109579, this patch exposes `runRegionDCE` and
`eraseUnreachableBlocks` so they can be used as separate utilities in
other passes.

Reviewed By: rriddle, mehdi_amini

Differential Revision: https://reviews.llvm.org/D114160

diff --git a/mlir/include/mlir/Transforms/RegionUtils.h b/mlir/include/mlir/Transforms/RegionUtils.h
index c87f943..109b76c 100644 (file)
--- a/mlir/include/mlir/Transforms/RegionUtils.h
+++ b/mlir/include/mlir/Transforms/RegionUtils.h
@@ -59,6 +59,16 @@ void getUsedValuesDefinedAbove(MutableArrayRef<Region> regions,
 LogicalResult simplifyRegions(RewriterBase &rewriter,
                               MutableArrayRef<Region> regions);
 
+/// Erase the unreachable blocks within the provided regions. Returns success
+/// if any blocks were erased, failure otherwise.
+LogicalResult eraseUnreachableBlocks(RewriterBase &rewriter,
+                                     MutableArrayRef<Region> regions);
+
+/// This function returns success if any operations or arguments were deleted,
+/// failure otherwise.
+LogicalResult runRegionDCE(RewriterBase &rewriter,
+                           MutableArrayRef<Region> regions);
+
 } // namespace mlir
 
 #endif // MLIR_TRANSFORMS_REGIONUTILS_H_

diff --git a/mlir/lib/Transforms/Utils/RegionUtils.cpp b/mlir/lib/Transforms/Utils/RegionUtils.cpp
index 26868d1..d7d8661 100644 (file)
--- a/mlir/lib/Transforms/Utils/RegionUtils.cpp
+++ b/mlir/lib/Transforms/Utils/RegionUtils.cpp
@@ -76,8 +76,8 @@ void mlir::getUsedValuesDefinedAbove(MutableArrayRef<Region> regions,
 /// Erase the unreachable blocks within the provided regions. Returns success
 /// if any blocks were erased, failure otherwise.
 // TODO: We could likely merge this with the DCE algorithm below.
-static LogicalResult eraseUnreachableBlocks(RewriterBase &rewriter,
-                                            MutableArrayRef<Region> regions) {
+LogicalResult mlir::eraseUnreachableBlocks(RewriterBase &rewriter,
+                                           MutableArrayRef<Region> regions) {
   // Set of blocks found to be reachable within a given region.
   llvm::df_iterator_default_set<Block *, 16> reachable;
   // If any blocks were found to be dead.
@@ -364,8 +364,8 @@ static LogicalResult deleteDeadness(RewriterBase &rewriter,
 //
 // This function returns success if any operations or arguments were deleted,
 // failure otherwise.
-static LogicalResult runRegionDCE(RewriterBase &rewriter,
-                                  MutableArrayRef<Region> regions) {
+LogicalResult mlir::runRegionDCE(RewriterBase &rewriter,
+                                 MutableArrayRef<Region> regions) {
   LiveMap liveMap;
   do {
     liveMap.resetChanged();