diff --git a/mlir/include/mlir/Transforms/GreedyPatternRewriteDriver.h b/mlir/include/mlir/Transforms/GreedyPatternRewriteDriver.h
--- a/mlir/include/mlir/Transforms/GreedyPatternRewriteDriver.h
+++ b/mlir/include/mlir/Transforms/GreedyPatternRewriteDriver.h
@@ -15,8 +15,10 @@
 #define MLIR_TRANSFORMS_GREEDYPATTERNREWRITEDRIVER_H_
 
 #include "mlir/Rewrite/FrozenRewritePatternSet.h"
+#include "mlir/Transforms/RegionUtils.h"
 
 namespace mlir {
+class SimplifyRegionsConfig;
 
 /// This class allows control over how the GreedyPatternRewriteDriver works.
 class GreedyRewriteConfig {
@@ -32,6 +34,9 @@
   // patterns.
   bool enableRegionSimplification = true;
 
+  /// Finer control on the regions simplification.
+  SimplifyRegionsConfig simplifyRegionsConfig;
+
   /// This specifies the maximum number of times the rewriter will iterate
   /// between applying patterns and simplifying regions.
   unsigned maxIterations = 10;
diff --git a/mlir/include/mlir/Transforms/RegionUtils.h b/mlir/include/mlir/Transforms/RegionUtils.h
--- a/mlir/include/mlir/Transforms/RegionUtils.h
+++ b/mlir/include/mlir/Transforms/RegionUtils.h
@@ -17,6 +17,19 @@
 namespace mlir {
 class RewriterBase;
 
+/// This class allows control over how the simplyRegions works.
+class SimplifyRegionsConfig {
+public:
+  /// Erase the unreachable blocks within the provided regions.
+  bool eraseUnreachableBlocks = true;
+  /// Performs a simple dead code elimination algorithm over the
+  /// given regions.
+  bool eliminateDeadOpsOrArgs = true;
+  /// Identify identical blocks within the given region and merge them,
+  /// inserting new block arguments as necessary.
+  bool mergeIdenticalBlocks = true;
+};
+
 /// Check if all values in the provided range are defined above the `limit`
 /// region.  That is, if they are defined in a region that is a proper ancestor
 /// of `limit`.
@@ -57,7 +70,8 @@
 /// of the regions were simplified, failure otherwise. The provided rewriter is
 /// used to notify callers of operation and block deletion.
 LogicalResult simplifyRegions(RewriterBase &rewriter,
-                              MutableArrayRef<Region> regions);
+                              MutableArrayRef<Region> regions,
+                              const SimplifyRegionsConfig &config);
 
 } // namespace mlir
 
diff --git a/mlir/lib/Transforms/Utils/GreedyPatternRewriteDriver.cpp b/mlir/lib/Transforms/Utils/GreedyPatternRewriteDriver.cpp
--- a/mlir/lib/Transforms/Utils/GreedyPatternRewriteDriver.cpp
+++ b/mlir/lib/Transforms/Utils/GreedyPatternRewriteDriver.cpp
@@ -221,7 +221,8 @@
     // After applying patterns, make sure that the CFG of each of the regions
     // is kept up to date.
     if (config.enableRegionSimplification)
-      changed |= succeeded(simplifyRegions(*this, regions));
+      changed |= succeeded(
+          simplifyRegions(*this, regions, config.simplifyRegionsConfig));
   } while (changed && ++iteration < config.maxIterations);
 
   // Whether the rewrite converges, i.e. wasn't changed in the last iteration.
diff --git a/mlir/lib/Transforms/Utils/RegionUtils.cpp b/mlir/lib/Transforms/Utils/RegionUtils.cpp
--- a/mlir/lib/Transforms/Utils/RegionUtils.cpp
+++ b/mlir/lib/Transforms/Utils/RegionUtils.cpp
@@ -706,11 +706,18 @@
 /// elimination, as well as some other DCE. This function returns success if any
 /// of the regions were simplified, failure otherwise.
 LogicalResult mlir::simplifyRegions(RewriterBase &rewriter,
-                                    MutableArrayRef<Region> regions) {
-  bool eliminatedBlocks = succeeded(eraseUnreachableBlocks(rewriter, regions));
-  bool eliminatedOpsOrArgs = succeeded(runRegionDCE(rewriter, regions));
-  bool mergedIdenticalBlocks =
-      succeeded(mergeIdenticalBlocks(rewriter, regions));
+                                    MutableArrayRef<Region> regions,
+                                    const SimplifyRegionsConfig &config) {
+  bool eliminatedBlocks = true;
+  bool eliminatedOpsOrArgs = true;
+  bool mergedIdenticalBlocks = true;
+
+  if (config.eraseUnreachableBlocks)
+    eliminatedBlocks = succeeded(eraseUnreachableBlocks(rewriter, regions));
+  if (config.eliminateDeadOpsOrArgs)
+    eliminatedOpsOrArgs = succeeded(runRegionDCE(rewriter, regions));
+  if (config.mergeIdenticalBlocks)
+    mergedIdenticalBlocks = succeeded(mergeIdenticalBlocks(rewriter, regions));
   return success(eliminatedBlocks || eliminatedOpsOrArgs ||
                  mergedIdenticalBlocks);
 }