[Openmp-commits] [openmp] [OMPT] Set default values for tsan function pointers (PR #93568)

[via Openmp-commits]

https://github.com/jprotze updated https://github.com/llvm/llvm-project/pull/93568

>From 1c7f35cb363e60825c1c1714c11fe5bab9b5816f Mon Sep 17 00:00:00 2001
From: zhangfenglei <zhangfenglei at huawei.com>
Date: Tue, 28 May 2024 14:56:23 +0800
Subject: [PATCH 1/2] [OMPT] Set default values for tsan function pointers

Avoid calling NULL function pointers in cases where
ompt_start_tool succeeds but those tsan functions
do not really exist.
---
 openmp/tools/archer/ompt-tsan.cpp | 32 +++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/openmp/tools/archer/ompt-tsan.cpp b/openmp/tools/archer/ompt-tsan.cpp
index de77e25db2d39..4d577d231703c 100644
--- a/openmp/tools/archer/ompt-tsan.cpp
+++ b/openmp/tools/archer/ompt-tsan.cpp
@@ -19,6 +19,7 @@
 #include <cassert>
 #include <cstdlib>
 #include <cstring>
+#include <dlfcn.h>
 #include <inttypes.h>
 #include <iostream>
 #include <list>
@@ -29,7 +30,6 @@
 #include <unistd.h>
 #include <unordered_map>
 #include <vector>
-#include <dlfcn.h>
 
 #include "omp-tools.h"
 
@@ -146,18 +146,27 @@ void __attribute__((weak)) __tsan_flush_memory() {}
 static ArcherFlags *archer_flags;
 
 #ifndef TsanHappensBefore
+
+template <typename... Args> static void __tsan_func(Args...) {}
+
+#define DECLARE_TSAN_FUNCTION(name, ...)                                       \
+  static void (*name)(__VA_ARGS__) = __tsan_func<__VA_ARGS__>;
+
 // Thread Sanitizer is a tool that finds races in code.
 // See http://code.google.com/p/data-race-test/wiki/DynamicAnnotations .
 // tsan detects these exact functions by name.
 extern "C" {
-static void (*AnnotateHappensAfter)(const char *, int, const volatile void *);
-static void (*AnnotateHappensBefore)(const char *, int, const volatile void *);
-static void (*AnnotateIgnoreWritesBegin)(const char *, int);
-static void (*AnnotateIgnoreWritesEnd)(const char *, int);
-static void (*AnnotateNewMemory)(const char *, int, const volatile void *,
-                                 size_t);
-static void (*__tsan_func_entry)(const void *);
-static void (*__tsan_func_exit)(void);
+DECLARE_TSAN_FUNCTION(AnnotateHappensAfter, const char *, int,
+                      const volatile void *)
+DECLARE_TSAN_FUNCTION(AnnotateHappensBefore, const char *, int,
+                      const volatile void *)
+DECLARE_TSAN_FUNCTION(AnnotateIgnoreWritesBegin, const char *, int)
+DECLARE_TSAN_FUNCTION(AnnotateIgnoreWritesEnd, const char *, int)
+DECLARE_TSAN_FUNCTION(AnnotateNewMemory, const char *, int,
+                      const volatile void *, size_t)
+DECLARE_TSAN_FUNCTION(__tsan_func_entry, const void *)
+DECLARE_TSAN_FUNCTION(__tsan_func_exit)
+
 static int (*RunningOnValgrind)(void);
 }
 
@@ -1142,7 +1151,10 @@ static void ompt_tsan_mutex_released(ompt_mutex_t kind, ompt_wait_id_t wait_id,
 
 #define findTsanFunction(f, fSig)                                              \
   do {                                                                         \
-    if (NULL == (f = fSig dlsym(RTLD_DEFAULT, #f)))                            \
+    void *fp = dlsym(RTLD_DEFAULT, #f);                                        \
+    if (fp)                                                                    \
+      f = fSig fp;                                                             \
+    else                                                                       \
       printf("Unable to find TSan function " #f ".\n");                        \
   } while (0)
 

>From 86029b9e3bb5a5ea049d140fa9ca0ec644b880bb Mon Sep 17 00:00:00 2001
From: Joachim <protze at rz.rwth-aachen.de>
Date: Tue, 28 May 2024 19:38:43 +0200
Subject: [PATCH 2/2] Apply suggestions from code review

---
 openmp/tools/archer/ompt-tsan.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/openmp/tools/archer/ompt-tsan.cpp b/openmp/tools/archer/ompt-tsan.cpp
index 4d577d231703c..d7658077e83ae 100644
--- a/openmp/tools/archer/ompt-tsan.cpp
+++ b/openmp/tools/archer/ompt-tsan.cpp
@@ -147,10 +147,10 @@ static ArcherFlags *archer_flags;
 
 #ifndef TsanHappensBefore
 
-template <typename... Args> static void __tsan_func(Args...) {}
+template <typename... Args> static void __ompt_tsan_func(Args...) {}
 
 #define DECLARE_TSAN_FUNCTION(name, ...)                                       \
-  static void (*name)(__VA_ARGS__) = __tsan_func<__VA_ARGS__>;
+  static void (*name)(__VA_ARGS__) = __ompt_tsan_func<__VA_ARGS__>;
 
 // Thread Sanitizer is a tool that finds races in code.
 // See http://code.google.com/p/data-race-test/wiki/DynamicAnnotations .
@@ -167,6 +167,7 @@ DECLARE_TSAN_FUNCTION(AnnotateNewMemory, const char *, int,
 DECLARE_TSAN_FUNCTION(__tsan_func_entry, const void *)
 DECLARE_TSAN_FUNCTION(__tsan_func_exit)
 
+// RunningOnValgrind is used to detect absence of TSan and must intentionally be a nullptr.
 static int (*RunningOnValgrind)(void);
 }