[Mlir-commits] [mlir] [MLIR] Fix crash when using --mlir-timing (PR #109463)

[llvmlistbot at llvm.org]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-mlir-core

Author: Ian Wood (IanWood1)

<details>
<summary>Changes</summary>

Fixes use-after-free when a pipeline fails and `--mlir-timing` is used. The `TimingScope` objects in `activeThreadTimers` access `ownedTimingManager` in their destructor, so `activeThreadTimers` must be destroyed before `ownedTimingManager` is.

This doesn't affect running individual passes (only pipelines) because `PassTiming::runAfterPassFailed` clears `activeThreadTimers` after a pass fails.

---
Full diff: https://github.com/llvm/llvm-project/pull/109463.diff


1 Files Affected:

- (modified) mlir/lib/Pass/PassTiming.cpp (+3-3) 


``````````diff
diff --git a/mlir/lib/Pass/PassTiming.cpp b/mlir/lib/Pass/PassTiming.cpp
index 9554c5dd9cb19c..45852455aa7370 100644
--- a/mlir/lib/Pass/PassTiming.cpp
+++ b/mlir/lib/Pass/PassTiming.cpp
@@ -35,9 +35,6 @@ struct PassTiming : public PassInstrumentation {
   /// parent thread into which the new thread should be nested.
   DenseMap<PipelineParentInfo, unsigned> parentTimerIndices;
 
-  /// A stack of the currently active timing scopes per thread.
-  DenseMap<uint64_t, SmallVector<TimingScope, 4>> activeThreadTimers;
-
   /// The timing manager owned by this instrumentation (in case timing was
   /// enabled by the user on the pass manager without providing an external
   /// timing manager). This *must* appear before the `ownedTimingScope` to
@@ -46,6 +43,9 @@ struct PassTiming : public PassInstrumentation {
   std::unique_ptr<TimingManager> ownedTimingManager;
   TimingScope ownedTimingScope;
 
+  /// A stack of the currently active timing scopes per thread.
+  DenseMap<uint64_t, SmallVector<TimingScope, 4>> activeThreadTimers;
+
   /// The root timing scope into which timing is reported.
   TimingScope &rootScope;
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/109463