diff --git a/mlir/include/mlir/Transforms/Passes.td b/mlir/include/mlir/Transforms/Passes.td
--- a/mlir/include/mlir/Transforms/Passes.td
+++ b/mlir/include/mlir/Transforms/Passes.td
@@ -617,7 +617,9 @@
   let constructor = "mlir::createPrintOpStatsPass()";
   let options = [
     Option<"topKLocs", "top-k-locs", "int64_t",
-           /*default=*/"0", "Print top-k locations by number of operations">
+           /*default=*/"0", "Print top-k locations by number of operations">,
+    Option<"topKLocsHist", "top-k-locs-hist", "bool",
+           /*default=*/"false", "Print op name histogram for top-k locations">
   ];
 }
 
diff --git a/mlir/lib/Transforms/OpStats.cpp b/mlir/lib/Transforms/OpStats.cpp
--- a/mlir/lib/Transforms/OpStats.cpp
+++ b/mlir/lib/Transforms/OpStats.cpp
@@ -18,6 +18,16 @@
 using namespace mlir;
 
 namespace {
+struct OpCounter {
+  void increment(StringRef opName) {
+    ++map[opName];
+    ++total;
+  }
+
+  llvm::StringMap<int64_t> map;
+  int64_t total;
+};
+
 struct PrintOpStatsPass : public PrintOpStatsBase<PrintOpStatsPass> {
   explicit PrintOpStatsPass(raw_ostream &os = llvm::errs()) : os(os) {}
 
@@ -30,9 +40,12 @@
   // Print top-k locations by number of operations.
   void printTopLocations();
 
+  // Print a histogram of op names, sorted by op name.
+  void printOpNameHistogram(const llvm::StringMap<int64_t> &count);
+
 private:
   llvm::StringMap<int64_t> opCount;
-  llvm::DenseMap<Location, int64_t> opCountByLoc;
+  llvm::DenseMap<Location, OpCounter> opCountByLoc;
 
   raw_ostream &os;
 };
@@ -46,7 +59,7 @@
   // Compute the operation statistics for the currently visited operation.
   getOperation()->walk([&](Operation *op) {
     ++opCount[op->getName().getStringRef()];
-    ++opCountByLoc[op->getLoc()];
+    opCountByLoc[op->getLoc()].increment(op->getName().getStringRef());
   });
 
   printSummary();
@@ -58,7 +71,12 @@
 void PrintOpStatsPass::printSummary() {
   os << "Operations encountered:\n";
   os << "-----------------------\n";
-  SmallVector<StringRef, 64> sorted(opCount.keys());
+  printOpNameHistogram(opCount);
+}
+
+void PrintOpStatsPass::printOpNameHistogram(
+    const llvm::StringMap<int64_t> &count) {
+  SmallVector<StringRef, 64> sorted(count.keys());
   llvm::sort(sorted);
 
   // Split an operation name from its dialect prefix.
@@ -89,8 +107,8 @@
       os << llvm::right_justify(dialectName, maxLenDialect + 2) << '.';
 
     // Left justify the operation name.
-    os << llvm::left_justify(opName, maxLenOpName) << " , " << opCount[key]
-       << '\n';
+    os << llvm::left_justify(opName, maxLenOpName) << " , "
+       << count.find(key)->second << '\n';
   }
 }
 
@@ -100,15 +118,16 @@
      << "--------------------------------------\n";
 
   // Sort by value (descending).
-  using EntryTy = std::pair<Location, int64_t>;
+  using EntryTy = std::pair<Location, OpCounter>;
   std::vector<EntryTy> sorted;
   for (const auto &it : opCountByLoc)
     sorted.push_back(it);
-  llvm::sort(sorted,
-             [](EntryTy e1, EntryTy e2) { return e1.second > e2.second; });
+  llvm::sort(sorted, [](EntryTy e1, EntryTy e2) {
+    return e1.second.total > e2.second.total;
+  });
 
   // Take top entries.
-  int64_t numLocs = sorted.size() < topKLocs ? sorted.size() : topKLocs;
+  int64_t numLocs = std::min<int64_t>(sorted.size(), topKLocs);
   for (int i = 0; i < numLocs; ++i) {
     std::string buffer;
     llvm::raw_string_ostream strOs(buffer);
@@ -122,7 +141,10 @@
     else
       os << "..." << str.substr(locSize - kMaxLocLen);
 
-    os << " , " << sorted[i].second << '\n';
+    os << " , " << sorted[i].second.total << '\n';
+
+    if (topKLocsHist)
+      printOpNameHistogram(sorted[i].second.map);
   }
 }
 
diff --git a/mlir/test/IR/op-stats.mlir b/mlir/test/IR/op-stats.mlir
--- a/mlir/test/IR/op-stats.mlir
+++ b/mlir/test/IR/op-stats.mlir
@@ -1,4 +1,4 @@
-// RUN: mlir-opt -allow-unregistered-dialect -print-op-stats="top-k-locs=5" %s -o=/dev/null 2>&1 | FileCheck %s
+// RUN: mlir-opt -allow-unregistered-dialect -print-op-stats="top-k-locs=5 top-k-locs-hist" %s -o=/dev/null 2>&1 | FileCheck %s
 
 func @main(tensor<4xf32>, tensor<4xf32>) -> tensor<4xf32> {
 ^bb0(%arg0: tensor<4xf32>, %arg1: tensor<4xf32>):