[mlir] Enhance TimingManager Printing Flexibility (#85821)

Revise the printing functionality of TimingManager to accommodate
various output formats. At present, TimingManager is limited to
outputting data solely in plain text format. To overcome this
limitation, I have introduced an abstract class that serves as the
foundation for printing. This approach allows users to implement
additional output formats by extending this abstract class. As part of
this update, I have integrated support for JSON as a new output format,
enhancing the ease of parsing for subsequent processing scripts.

4 files changed, 297 insertions, 94 deletions

diff --git a/mlir/docs/PassManagement.md b/mlir/docs/PassManagement.md
index c9d705f..e9ecb99 100644
--- a/mlir/docs/PassManagement.md
+++ b/mlir/docs/PassManagement.md
@@ -1124,17 +1124,44 @@ pipeline. This display mode is available in mlir-opt via
 $ mlir-opt foo.mlir -mlir-disable-threading -pass-pipeline='builtin.module(func.func(cse,canonicalize),convert-func-to-llvm)' -mlir-timing -mlir-timing-display=list
 
 ===-------------------------------------------------------------------------===
-                      ... Pass execution timing report ...
+                         ... Execution time report ...
 ===-------------------------------------------------------------------------===
-  Total Execution Time: 0.0203 seconds
-
-   ---Wall Time---  --- Name ---
-   0.0047 ( 55.9%)  Canonicalizer
-   0.0019 ( 22.2%)  VerifierPass
-   0.0016 ( 18.5%)  LLVMLoweringPass
-   0.0003 (  3.4%)  CSE
-   0.0002 (  1.9%)  (A) DominanceInfo
-   0.0084 (100.0%)  Total
+  Total Execution Time: 0.0135 seconds
+
+  ----Wall Time----  ----Name----
+    0.0135 (100.0%)  root
+    0.0041 ( 30.1%)  Parser
+    0.0018 ( 13.3%)  ConvertFuncToLLVMPass
+    0.0011 (  8.2%)  Output
+    0.0007 (  5.2%)  Pipeline Collection : ['func.func']
+    0.0006 (  4.6%)  'func.func' Pipeline
+    0.0005 (  3.5%)  Canonicalizer
+    0.0001 (  0.9%)  CSE
+    0.0001 (  0.5%)  (A) DataLayoutAnalysis
+    0.0000 (  0.1%)  (A) DominanceInfo
+    0.0058 ( 43.2%)  Rest
+    0.0135 (100.0%)  Total
+```
+
+The results can be displayed in JSON format via `-mlir-output-format=json`.
+
+```shell
+$ mlir-opt foo.mlir -mlir-disable-threading -pass-pipeline='builtin.module(func.func(cse,canonicalize),convert-func-to-llvm)' -mlir-timing -mlir-timing-display=list -mlir-output-format=json
+
+[
+{"wall": {"duration":   0.0135, "percentage": 100.0}, "name": "root"},
+{"wall": {"duration":   0.0041, "percentage":  30.1}, "name": "Parser"},
+{"wall": {"duration":   0.0018, "percentage":  13.3}, "name": "ConvertFuncToLLVMPass"},
+{"wall": {"duration":   0.0011, "percentage":   8.2}, "name": "Output"},
+{"wall": {"duration":   0.0007, "percentage":   5.2}, "name": "Pipeline Collection : ['func.func']"},
+{"wall": {"duration":   0.0006, "percentage":   4.6}, "name": "'func.func' Pipeline"},
+{"wall": {"duration":   0.0005, "percentage":   3.5}, "name": "Canonicalizer"},
+{"wall": {"duration":   0.0001, "percentage":   0.9}, "name": "CSE"},
+{"wall": {"duration":   0.0001, "percentage":   0.5}, "name": "(A) DataLayoutAnalysis"},
+{"wall": {"duration":   0.0000, "percentage":   0.1}, "name": "(A) DominanceInfo"},
+{"wall": {"duration":   0.0058, "percentage":  43.2}, "name": "Rest"},
+{"wall": {"duration":   0.0135, "percentage": 100.0}, "name": "Total"}
+]
 ```
 
 ##### Tree Display Mode
@@ -1149,21 +1176,48 @@ invalidated and recomputed. This is the default display mode.
 $ mlir-opt foo.mlir -mlir-disable-threading -pass-pipeline='builtin.module(func.func(cse,canonicalize),convert-func-to-llvm)' -mlir-timing
 
 ===-------------------------------------------------------------------------===
-                      ... Pass execution timing report ...
+                         ... Execution time report ...
 ===-------------------------------------------------------------------------===
-  Total Execution Time: 0.0249 seconds
-
-   ---Wall Time---  --- Name ---
-   0.0058 ( 70.8%)  'func.func' Pipeline
-   0.0004 (  4.3%)    CSE
-   0.0002 (  2.6%)      (A) DominanceInfo
-   0.0004 (  4.8%)    VerifierPass
-   0.0046 ( 55.4%)    Canonicalizer
-   0.0005 (  6.2%)    VerifierPass
-   0.0005 (  5.8%)  VerifierPass
-   0.0014 ( 17.2%)  LLVMLoweringPass
-   0.0005 (  6.2%)  VerifierPass
-   0.0082 (100.0%)  Total
+  Total Execution Time: 0.0127 seconds
+
+  ----Wall Time----  ----Name----
+    0.0038 ( 30.2%)  Parser
+    0.0006 (  4.8%)  'func.func' Pipeline
+    0.0001 (  0.9%)    CSE
+    0.0000 (  0.1%)      (A) DominanceInfo
+    0.0005 (  3.7%)    Canonicalizer
+    0.0017 ( 13.7%)  ConvertFuncToLLVMPass
+    0.0001 (  0.6%)    (A) DataLayoutAnalysis
+    0.0010 (  8.2%)  Output
+    0.0054 ( 42.5%)  Rest
+    0.0127 (100.0%)  Total
+```
+
+The results can be displayed in JSON format via `-mlir-output-format=json`.
+
+```shell
+$ mlir-opt foo.mlir -mlir-disable-threading -pass-pipeline='builtin.module(func.func(cse,canonicalize),convert-func-to-llvm)' -mlir-timing -mlir-output-format=json
+
+[
+{"wall": {"duration":   0.0038, "percentage":  30.2}, "name": "Parser", "passes": [
+{}]},
+{"wall": {"duration":   0.0006, "percentage":   4.8}, "name": "'func.func' Pipeline", "passes": [
+  {"wall": {"duration":   0.0001, "percentage":   0.9}, "name": "CSE", "passes": [
+    {"wall": {"duration":   0.0000, "percentage":   0.1}, "name": "(A) DominanceInfo", "passes": [
+    {}]},
+  {}]},
+  {"wall": {"duration":   0.0005, "percentage":   3.7}, "name": "Canonicalizer", "passes": [
+  {}]},
+{}]},
+{"wall": {"duration":   0.0017, "percentage":  13.7}, "name": "ConvertFuncToLLVMPass", "passes": [
+  {"wall": {"duration":   0.0001, "percentage":   0.6}, "name": "(A) DataLayoutAnalysis", "passes": [
+  {}]},
+{}]},
+{"wall": {"duration":   0.0010, "percentage":   8.2}, "name": "Output", "passes": [
+{}]},
+{"wall": {"duration":   0.0054, "percentage":  42.5}, "name": "Rest"},
+{"wall": {"duration":   0.0127, "percentage": 100.0}, "name": "Total"}
+]
 ```
 
 ##### Multi-threaded Pass Timing
diff --git a/mlir/include/mlir/Support/Timing.h b/mlir/include/mlir/Support/Timing.h
index bc3a642..a8a4bfd 100644
--- a/mlir/include/mlir/Support/Timing.h
+++ b/mlir/include/mlir/Support/Timing.h
@@ -321,6 +321,53 @@ private:
 };
 
 //===----------------------------------------------------------------------===//
+// OutputStrategy
+//===----------------------------------------------------------------------===//
+
+/// Simple record class to record timing information.
+struct TimeRecord {
+  TimeRecord(double wall = 0.0, double user = 0.0) : wall(wall), user(user) {}
+
+  TimeRecord &operator+=(const TimeRecord &other) {
+    wall += other.wall;
+    user += other.user;
+    return *this;
+  }
+
+  TimeRecord &operator-=(const TimeRecord &other) {
+    wall -= other.wall;
+    user -= other.user;
+    return *this;
+  }
+
+  double wall, user;
+};
+
+/// Facilities for printing timing reports to various output formats.
+///
+/// This is an abstract class that serves as the foundation for printing.
+/// Users can implement additional output formats by extending this abstract
+/// class.
+class OutputStrategy {
+public:
+  OutputStrategy(raw_ostream &os) : os(os) {}
+  virtual ~OutputStrategy() = default;
+
+  virtual void printHeader(const TimeRecord &total) = 0;
+  virtual void printFooter() = 0;
+  virtual void printTime(const TimeRecord &time, const TimeRecord &total) = 0;
+  virtual void printListEntry(StringRef name, const TimeRecord &time,
+                              const TimeRecord &total,
+                              bool lastEntry = false) = 0;
+  virtual void printTreeEntry(unsigned indent, StringRef name,
+                              const TimeRecord &time,
+                              const TimeRecord &total) = 0;
+  virtual void printTreeEntryEnd(unsigned indent, bool lastEntry = false) = 0;
+
+  raw_ostream &os;
+};
+
+//===----------------------------------------------------------------------===//
 // DefaultTimingManager
 //===----------------------------------------------------------------------===//
 
@@ -351,6 +398,15 @@ public:
     Tree,
   };
 
+  /// The different output formats for printing the timers.
+  enum class OutputFormat {
+    /// In this format the results are displayed in text format.
+    Text,
+
+    /// In this format the results are displayed in JSON format.
+    Json,
+  };
+
   DefaultTimingManager();
   DefaultTimingManager(DefaultTimingManager &&rhs);
   ~DefaultTimingManager() override;
@@ -372,10 +428,7 @@ public:
   DisplayMode getDisplayMode() const;
 
   /// Change the stream where the output will be printed to.
-  void setOutput(raw_ostream &os);
-
-  /// Return the current output stream where the output will be printed to.
-  raw_ostream &getOutput() const;
+  void setOutput(std::unique_ptr<OutputStrategy> output);
 
   /// Print and clear the timing results. Only call this when there are no more
   /// references to nested timers around, as printing post-processes and clears
@@ -408,6 +461,7 @@ protected:
 
 private:
   const std::unique_ptr<detail::DefaultTimingManagerImpl> impl;
+  std::unique_ptr<OutputStrategy> out;
 };
 
 /// Register a set of useful command-line options that can be used to configure
diff --git a/mlir/lib/Support/Timing.cpp b/mlir/lib/Support/Timing.cpp
index 2249312..1d6796e 100644
--- a/mlir/lib/Support/Timing.cpp
+++ b/mlir/lib/Support/Timing.cpp
@@ -32,6 +32,7 @@
 using namespace mlir;
 using namespace detail;
 using DisplayMode = DefaultTimingManager::DisplayMode;
+using OutputFormat = DefaultTimingManager::OutputFormat;
 
 constexpr llvm::StringLiteral kTimingDescription =
     "... Execution time report ...";
@@ -109,56 +110,105 @@ TimingIdentifier TimingIdentifier::get(StringRef str, TimingManager &tm) {
 
 namespace {
 
-/// Simple record class to record timing information.
-struct TimeRecord {
-  TimeRecord(double wall = 0.0, double user = 0.0) : wall(wall), user(user) {}
+class OutputTextStrategy : public OutputStrategy {
+public:
+  OutputTextStrategy(raw_ostream &os) : OutputStrategy(os) {}
+
+  void printHeader(const TimeRecord &total) override {
+    // Figure out how many spaces to description name.
+    unsigned padding = (80 - kTimingDescription.size()) / 2;
+    os << "===" << std::string(73, '-') << "===\n";
+    os.indent(padding) << kTimingDescription << '\n';
+    os << "===" << std::string(73, '-') << "===\n";
 
-  TimeRecord &operator+=(const TimeRecord &other) {
-    wall += other.wall;
-    user += other.user;
-    return *this;
+    // Print the total time followed by the section headers.
+    os << llvm::format("  Total Execution Time: %.4f seconds\n\n", total.wall);
+    if (total.user != total.wall)
+      os << "  ----User Time----";
+    os << "  ----Wall Time----  ----Name----\n";
   }
 
-  TimeRecord &operator-=(const TimeRecord &other) {
-    wall -= other.wall;
-    user -= other.user;
-    return *this;
+  void printFooter() override { os.flush(); }
+
+  void printTime(const TimeRecord &time, const TimeRecord &total) override {
+    if (total.user != total.wall) {
+      os << llvm::format("  %8.4f (%5.1f%%)", time.user,
+                         100.0 * time.user / total.user);
+    }
+    os << llvm::format("  %8.4f (%5.1f%%)  ", time.wall,
+                       100.0 * time.wall / total.wall);
   }
 
-  /// Print the current time record to 'os', with a breakdown showing
-  /// contributions to the give 'total' time record.
-  void print(raw_ostream &os, const TimeRecord &total) {
-    if (total.user != total.wall)
-      os << llvm::format("  %8.4f (%5.1f%%)", user, 100.0 * user / total.user);
-    os << llvm::format("  %8.4f (%5.1f%%)  ", wall, 100.0 * wall / total.wall);
+  void printListEntry(StringRef name, const TimeRecord &time,
+                      const TimeRecord &total, bool lastEntry) override {
+    printTime(time, total);
+    os << name << "\n";
+  }
+
+  void printTreeEntry(unsigned indent, StringRef name, const TimeRecord &time,
+                      const TimeRecord &total) override {
+    printTime(time, total);
+    os.indent(indent) << name << "\n";
   }
 
-  double wall, user;
+  void printTreeEntryEnd(unsigned indent, bool lastEntry) override {}
 };
 
-} // namespace
+class OutputJsonStrategy : public OutputStrategy {
+public:
+  OutputJsonStrategy(raw_ostream &os) : OutputStrategy(os) {}
 
-/// Utility to print a single line entry in the timer output.
-static void printTimeEntry(raw_ostream &os, unsigned indent, StringRef name,
-                           TimeRecord time, TimeRecord total) {
-  time.print(os, total);
-  os.indent(indent) << name << "\n";
-}
+  void printHeader(const TimeRecord &total) override { os << "[" << "\n"; }
 
-/// Utility to print the timer heading information.
-static void printTimeHeader(raw_ostream &os, TimeRecord total) {
-  // Figure out how many spaces to description name.
-  unsigned padding = (80 - kTimingDescription.size()) / 2;
-  os << "===" << std::string(73, '-') << "===\n";
-  os.indent(padding) << kTimingDescription << '\n';
-  os << "===" << std::string(73, '-') << "===\n";
-
-  // Print the total time followed by the section headers.
-  os << llvm::format("  Total Execution Time: %.4f seconds\n\n", total.wall);
-  if (total.user != total.wall)
-    os << "  ----User Time----";
-  os << "  ----Wall Time----  ----Name----\n";
-}
+  void printFooter() override {
+    os << "]" << "\n";
+    os.flush();
+  }
+
+  void printTime(const TimeRecord &time, const TimeRecord &total) override {
+    if (total.user != total.wall) {
+      os << "\"user\": {";
+      os << "\"duration\": " << llvm::format("%8.4f", time.user) << ", ";
+      os << "\"percentage\": "
+         << llvm::format("%5.1f", 100.0 * time.user / total.user);
+      os << "}, ";
+    }
+    os << "\"wall\": {";
+    os << "\"duration\": " << llvm::format("%8.4f", time.wall) << ", ";
+    os << "\"percentage\": "
+       << llvm::format("%5.1f", 100.0 * time.wall / total.wall);
+    os << "}";
+  }
+
+  void printListEntry(StringRef name, const TimeRecord &time,
+                      const TimeRecord &total, bool lastEntry) override {
+    os << "{";
+    printTime(time, total);
+    os << ", \"name\": " << "\"" << name << "\"";
+    os << "}";
+    if (!lastEntry)
+      os << ",";
+    os << "\n";
+  }
+
+  void printTreeEntry(unsigned indent, StringRef name, const TimeRecord &time,
+                      const TimeRecord &total) override {
+    os.indent(indent) << "{";
+    printTime(time, total);
+    os << ", \"name\": " << "\"" << name << "\"";
+    os << ", \"passes\": [" << "\n";
+  }
+
+  void printTreeEntryEnd(unsigned indent, bool lastEntry) override {
+    os.indent(indent) << "{}]";
+    os << "}";
+    if (!lastEntry)
+      os << ",";
+    os << "\n";
+  }
+};
+
+} // namespace
 
 //===----------------------------------------------------------------------===//
 // Timer Implementation for DefaultTimingManager
@@ -176,7 +226,8 @@ public:
   using ChildrenMap = llvm::MapVector<const void *, std::unique_ptr<TimerImpl>>;
   using AsyncChildrenMap = llvm::DenseMap<uint64_t, ChildrenMap>;
 
-  TimerImpl(std::string &&name) : threadId(llvm::get_threadid()), name(name) {}
+  TimerImpl(std::string &&name, std::unique_ptr<OutputStrategy> &output)
+      : threadId(llvm::get_threadid()), name(name), output(output) {}
 
   /// Start the timer.
   void start() { startTime = std::chrono::steady_clock::now(); }
@@ -206,7 +257,7 @@ public:
   TimerImpl *nestTail(std::unique_ptr<TimerImpl> &child,
                       function_ref<std::string()> nameBuilder) {
     if (!child)
-      child = std::make_unique<TimerImpl>(nameBuilder());
+      child = std::make_unique<TimerImpl>(nameBuilder(), output);
     return child.get();
   }
 
@@ -320,7 +371,7 @@ public:
   }
 
   /// Print the timing result in list mode.
-  void printAsList(raw_ostream &os, TimeRecord total) {
+  void printAsList(TimeRecord total) {
     // Flatten the leaf timers in the tree and merge them by name.
     llvm::StringMap<TimeRecord> mergedTimers;
     std::function<void(TimerImpl *)> addTimer = [&](TimerImpl *timer) {
@@ -343,34 +394,37 @@ public:
 
     // Print the timing information sequentially.
     for (auto &timeData : timerNameAndTime)
-      printTimeEntry(os, 0, timeData.first, timeData.second, total);
+      output->printListEntry(timeData.first, timeData.second, total);
   }
 
   /// Print the timing result in tree mode.
-  void printAsTree(raw_ostream &os, TimeRecord total, unsigned indent = 0) {
+  void printAsTree(TimeRecord total, unsigned indent = 0) {
     unsigned childIndent = indent;
     if (!hidden) {
-      printTimeEntry(os, indent, name, getTimeRecord(), total);
+      output->printTreeEntry(indent, name, getTimeRecord(), total);
       childIndent += 2;
     }
     for (auto &child : children) {
-      child.second->printAsTree(os, total, childIndent);
+      child.second->printAsTree(total, childIndent);
+    }
+    if (!hidden) {
+      output->printTreeEntryEnd(indent);
     }
   }
 
   /// Print the current timing information.
-  void print(raw_ostream &os, DisplayMode displayMode) {
+  void print(DisplayMode displayMode) {
     // Print the banner.
     auto total = getTimeRecord();
-    printTimeHeader(os, total);
+    output->printHeader(total);
 
     // Defer to a specialized printer for each display mode.
     switch (displayMode) {
     case DisplayMode::List:
-      printAsList(os, total);
+      printAsList(total);
       break;
     case DisplayMode::Tree:
-      printAsTree(os, total);
+      printAsTree(total);
       break;
     }
 
@@ -379,9 +433,9 @@ public:
     auto rest = total;
     for (auto &child : children)
       rest -= child.second->getTimeRecord();
-    printTimeEntry(os, 0, "Rest", rest, total);
-    printTimeEntry(os, 0, "Total", total, total);
-    os.flush();
+    output->printListEntry("Rest", rest, total);
+    output->printListEntry("Total", total, total, /*lastEntry=*/true);
+    output->printFooter();
   }
 
   /// The last time instant at which the timer was started.
@@ -415,6 +469,8 @@ public:
 
   /// Mutex for the async children.
   std::mutex asyncMutex;
+
+  std::unique_ptr<OutputStrategy> &output;
 };
 
 } // namespace
@@ -435,9 +491,6 @@ public:
   /// The configured display mode.
   DisplayMode displayMode = DisplayMode::Tree;
 
-  /// The stream where we should print our output. This will always be non-null.
-  raw_ostream *output = &llvm::errs();
-
   /// The root timer.
   std::unique_ptr<TimerImpl> rootTimer;
 };
@@ -469,26 +522,22 @@ DefaultTimingManager::DisplayMode DefaultTimingManager::getDisplayMode() const {
 }
 
 /// Change the stream where the output will be printed to.
-void DefaultTimingManager::setOutput(raw_ostream &os) { impl->output = &os; }
-
-/// Return the current output stream where the output will be printed to.
-raw_ostream &DefaultTimingManager::getOutput() const {
-  assert(impl->output);
-  return *impl->output;
+void DefaultTimingManager::setOutput(std::unique_ptr<OutputStrategy> output) {
+  out = std::move(output);
 }
 
 /// Print and clear the timing results.
 void DefaultTimingManager::print() {
   if (impl->enabled) {
     impl->rootTimer->finalize();
-    impl->rootTimer->print(*impl->output, impl->displayMode);
+    impl->rootTimer->print(impl->displayMode);
   }
   clear();
 }
 
 /// Clear the timing results.
 void DefaultTimingManager::clear() {
-  impl->rootTimer = std::make_unique<TimerImpl>("root");
+  impl->rootTimer = std::make_unique<TimerImpl>("root", out);
   impl->rootTimer->hidden = true;
 }
 
@@ -500,13 +549,13 @@ void DefaultTimingManager::dumpTimers(raw_ostream &os) {
 /// Debug print the timers as a list.
 void DefaultTimingManager::dumpAsList(raw_ostream &os) {
   impl->rootTimer->finalize();
-  impl->rootTimer->print(os, DisplayMode::List);
+  impl->rootTimer->print(DisplayMode::List);
 }
 
 /// Debug print the timers as a tree.
 void DefaultTimingManager::dumpAsTree(raw_ostream &os) {
   impl->rootTimer->finalize();
-  impl->rootTimer->print(os, DisplayMode::Tree);
+  impl->rootTimer->print(DisplayMode::Tree);
 }
 
 std::optional<void *> DefaultTimingManager::rootTimer() {
@@ -549,6 +598,13 @@ struct DefaultTimingManagerOptions {
                      "display the results in a list sorted by total time"),
           clEnumValN(DisplayMode::Tree, "tree",
                      "display the results ina with a nested tree view"))};
+  llvm::cl::opt<OutputFormat> outputFormat{
+      "mlir-output-format", llvm::cl::desc("Output format for timing data"),
+      llvm::cl::init(OutputFormat::Text),
+      llvm::cl::values(clEnumValN(OutputFormat::Text, "text",
+                                  "display the results in text format"),
+                       clEnumValN(OutputFormat::Json, "json",
+                                  "display the results in JSON format"))};
 };
 } // namespace
 
@@ -564,4 +620,11 @@ void mlir::applyDefaultTimingManagerCLOptions(DefaultTimingManager &tm) {
     return;
   tm.setEnabled(options->timing);
   tm.setDisplayMode(options->displayMode);
+
+  std::unique_ptr<OutputStrategy> printer;
+  if (options->outputFormat == OutputFormat::Text)
+    printer = std::make_unique<OutputTextStrategy>(llvm::errs());
+  else if (options->outputFormat == OutputFormat::Json)
+    printer = std::make_unique<OutputJsonStrategy>(llvm::errs());
+  tm.setOutput(std::move(printer));
 }
diff --git a/mlir/test/Pass/pass-timing.mlir b/mlir/test/Pass/pass-timing.mlir
index bd5d611..cfb4b74 100644
--- a/mlir/test/Pass/pass-timing.mlir
+++ b/mlir/test/Pass/pass-timing.mlir
@@ -1,5 +1,7 @@
 // RUN: mlir-opt %s -mlir-disable-threading=true -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=list 2>&1 | FileCheck -check-prefix=LIST %s
+// RUN: mlir-opt %s -mlir-disable-threading=true -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=list -mlir-output-format=json 2>&1 | FileCheck -check-prefix=LIST-JSON %s
 // RUN: mlir-opt %s -mlir-disable-threading=true -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=tree 2>&1 | FileCheck -check-prefix=PIPELINE %s
+// RUN: mlir-opt %s -mlir-disable-threading=true -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=tree -mlir-output-format=json 2>&1 | FileCheck -check-prefix=PIPELINE-JSON %s
 // RUN: mlir-opt %s -mlir-disable-threading=false -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=list 2>&1 | FileCheck -check-prefix=MT_LIST %s
 // RUN: mlir-opt %s -mlir-disable-threading=false -verify-each=true -pass-pipeline='builtin.module(func.func(cse,canonicalize,cse))' -mlir-timing -mlir-timing-display=tree 2>&1 | FileCheck -check-prefix=MT_PIPELINE %s
 // RUN: mlir-opt %s -mlir-disable-threading=true -verify-each=false -test-pm-nested-pipeline -mlir-timing -mlir-timing-display=tree 2>&1 | FileCheck -check-prefix=NESTED_PIPELINE %s
@@ -12,6 +14,14 @@
 // LIST-DAG: DominanceInfo
 // LIST: Total
 
+// LIST-JSON-NOT: Execution time report
+// LIST-JSON-NOT: Total Execution Time:
+// LIST-JSON-NOT: Name
+// LIST-JSON-DAG: "name": "Canonicalizer"}
+// LIST-JSON-DAG: "name": "CSE"}
+// LIST-JSON-DAG: "name": "(A) DominanceInfo"}
+// LIST-JSON: "name": "Total"}
+
 // PIPELINE: Execution time report
 // PIPELINE: Total Execution Time:
 // PIPELINE: Name
@@ -26,6 +36,28 @@
 // PIPELINE-NEXT: Rest
 // PIPELINE-NEXT: Total
 
+// PIPELINE-JSON-NOT: Execution time report
+// PIPELINE-JSON-NOT: Total Execution Time:
+// PIPELINE-JSON-NOT: Name
+// PIPELINE-JSON:      "name": "Parser", "passes": [
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: "name": "'func.func' Pipeline", "passes": [
+// PIPELINE-JSON-NEXT: "name": "CSE", "passes": [
+// PIPELINE-JSON-NEXT: "name": "(A) DominanceInfo", "passes": [
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: "name": "Canonicalizer", "passes": [
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: "name": "CSE", "passes": [
+// PIPELINE-JSON-NEXT: "name": "(A) DominanceInfo", "passes": [
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: "name": "Output", "passes": [
+// PIPELINE-JSON-NEXT: {}]},
+// PIPELINE-JSON-NEXT: "name": "Rest"
+// PIPELINE-JSON-NEXT: "name": "Total"
+
 // MT_LIST: Execution time report
 // MT_LIST: Total Execution Time:
 // MT_LIST: Name