From ed810da73270267082c347bc2919eebb7978a2fe Mon Sep 17 00:00:00 2001
From: Joachim Protze <protze@itc.rwth-aachen.de>
Date: Mon, 13 Jan 2020 22:12:48 -1000
Subject: [PATCH] [OpenMP][Tool] Improving stack trace for Archer

The OpenMP runtime is not instrumented, so entering the runtime leaves no hint
on the source line of the pragma on ThreadSanitizer's function stack.

This patch adds function entry/exit annotations for OpenMP parallel regions,
and synchronization regions (barrier, taskwait, taskgroup).

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D70408
---
 openmp/tools/archer/ompt-tsan.cpp | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/openmp/tools/archer/ompt-tsan.cpp b/openmp/tools/archer/ompt-tsan.cpp
index 552edf3af326..03a2f6c148fe 100644
--- a/openmp/tools/archer/ompt-tsan.cpp
+++ b/openmp/tools/archer/ompt-tsan.cpp
@@ -162,6 +162,8 @@ int __attribute__((weak)) RunningOnValgrind() {
   runOnTsan = 0;
   return 0;
 }
+void __attribute__((weak)) __tsan_func_entry(const void *call_pc) {}
+void __attribute__((weak)) __tsan_func_exit(void) {}
 #endif
 }
 
@@ -189,6 +191,10 @@ int __attribute__((weak)) RunningOnValgrind() {
   AnnotateNewMemory(__FILE__, __LINE__, addr, size)
 #endif
 
+// Function entry/exit
+#define TsanFuncEntry(pc) __tsan_func_entry(pc)
+#define TsanFuncExit() __tsan_func_exit()
+
 /// Required OMPT inquiry functions.
 static ompt_get_parallel_info_t ompt_get_parallel_info;
 static ompt_get_thread_data_t ompt_get_thread_data;
@@ -301,10 +307,13 @@ struct ParallelData {
   /// Two addresses for relationships with barriers.
   ompt_tsan_clockid Barrier[2];
 
+  const void *codePtr;
+
   void *GetParallelPtr() { return &(Barrier[1]); }
 
   void *GetBarrierPtr(unsigned Index) { return &(Barrier[Index]); }
 
+  ParallelData(const void *codeptr) : codePtr(codeptr) {}
   ~ParallelData() {
     TsanDeleteClock(&(Barrier[0]));
     TsanDeleteClock(&(Barrier[1]));
@@ -458,7 +467,7 @@ static void ompt_tsan_parallel_begin(ompt_data_t *parent_task_data,
                                      uint32_t requested_team_size,
                                      int flag,
                                      const void *codeptr_ra) {
-  ParallelData *Data = new ParallelData;
+  ParallelData *Data = new ParallelData(codeptr_ra);
   parallel_data->ptr = Data;
 
   TsanHappensBefore(Data->GetParallelPtr());
@@ -491,8 +500,12 @@ static void ompt_tsan_implicit_task(ompt_scope_endpoint_t endpoint,
                                     int type) {
   switch (endpoint) {
   case ompt_scope_begin:
+    if (type & ompt_task_initial) {
+      parallel_data->ptr = new ParallelData(nullptr);
+    }
     task_data->ptr = new TaskData(ToParallelData(parallel_data));
     TsanHappensAfter(ToParallelData(parallel_data)->GetParallelPtr());
+    TsanFuncEntry(ToParallelData(parallel_data)->codePtr);
     break;
   case ompt_scope_end:
     TaskData *Data = ToTaskData(task_data);
@@ -501,6 +514,7 @@ static void ompt_tsan_implicit_task(ompt_scope_endpoint_t endpoint,
     assert(Data->RefCount == 1 &&
            "All tasks should have finished at the implicit barrier!");
     delete Data;
+    TsanFuncExit();
     break;
   }
 }
@@ -513,6 +527,7 @@ static void ompt_tsan_sync_region(ompt_sync_region_t kind,
   TaskData *Data = ToTaskData(task_data);
   switch (endpoint) {
   case ompt_scope_begin:
+    TsanFuncEntry(codeptr_ra);
     switch (kind) {
       case ompt_sync_region_barrier_implementation:
       case ompt_sync_region_barrier_implicit:
@@ -546,6 +561,7 @@ static void ompt_tsan_sync_region(ompt_sync_region_t kind,
     }
     break;
   case ompt_scope_end:
+    TsanFuncExit();
     switch (kind) {
       case ompt_sync_region_barrier_implementation:
       case ompt_sync_region_barrier_implicit:
@@ -641,7 +657,7 @@ static void ompt_tsan_task_create(
     ompt_data_t *parallel_data;
     int team_size = 1;
     ompt_get_parallel_info(0, &parallel_data, &team_size);
-    ParallelData *PData = new ParallelData;
+    ParallelData *PData = new ParallelData(nullptr);
     parallel_data->ptr = PData;
 
     Data = new TaskData(PData);