From: Kuba Brecka <kuba.brecka@gmail.com>
Date: Tue, 2 Aug 2016 14:30:52 +0000 (+0000)
Subject: [tsan] Fix the behavior of OSAtomicTestAndClear
X-Git-Tag: llvmorg-4.0.0-rc1~13564
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3a748d60670c5dc81572ea680804b3e3486c20e0;p=platform%2Fupstream%2Fllvm.git

[tsan] Fix the behavior of OSAtomicTestAndClear

The system implementation of OSAtomicTestAndClear returns the original bit, but the TSan interceptor has a bug which always returns zero from the function. This patch fixes this and adds a test.

Differential Revision: https://reviews.llvm.org/D23061

llvm-svn: 277461
---

diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors_mac.cc b/compiler-rt/lib/tsan/rtl/tsan_interceptors_mac.cc
index 5939638..03cf54f 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interceptors_mac.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_interceptors_mac.cc
@@ -119,24 +119,23 @@ OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap32, __tsan_atomic32, a32,
 OSATOMIC_INTERCEPTORS_CAS(OSAtomicCompareAndSwap64, __tsan_atomic64, a64,
                           int64_t)
 
-#define OSATOMIC_INTERCEPTOR_BITOP(f, op, m, mo)              \
+#define OSATOMIC_INTERCEPTOR_BITOP(f, op, clear, mo)          \
   TSAN_INTERCEPTOR(bool, f, uint32_t n, volatile void *ptr) { \
     SCOPED_TSAN_INTERCEPTOR(f, n, ptr);                       \
     char *byte_ptr = ((char *)ptr) + (n >> 3);                \
-    char bit_index = n & 7;                                   \
-    char mask = m;                                            \
+    char bit = 0x80u >> (n & 7);                              \
+    char mask = clear ? ~bit : bit;                           \
     char orig_byte = op((a8 *)byte_ptr, mask, mo);            \
-    return orig_byte & mask;                                  \
+    return orig_byte & bit;                                   \
   }
 
-#define OSATOMIC_INTERCEPTORS_BITOP(f, op, m)                     \
-  OSATOMIC_INTERCEPTOR_BITOP(f, op, m, kMacOrderNonBarrier)       \
-  OSATOMIC_INTERCEPTOR_BITOP(f##Barrier, op, m, kMacOrderBarrier)
+#define OSATOMIC_INTERCEPTORS_BITOP(f, op, clear)               \
+  OSATOMIC_INTERCEPTOR_BITOP(f, op, clear, kMacOrderNonBarrier) \
+  OSATOMIC_INTERCEPTOR_BITOP(f##Barrier, op, clear, kMacOrderBarrier)
 
-OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndSet, __tsan_atomic8_fetch_or,
-                            0x80u >> bit_index)
+OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndSet, __tsan_atomic8_fetch_or, false)
 OSATOMIC_INTERCEPTORS_BITOP(OSAtomicTestAndClear, __tsan_atomic8_fetch_and,
-                            ~(0x80u >> bit_index))
+                            true)
 
 TSAN_INTERCEPTOR(void, OSAtomicEnqueue, OSQueueHead *list, void *item,
                  size_t offset) {
diff --git a/compiler-rt/test/tsan/Darwin/osatomics-bitops.mm b/compiler-rt/test/tsan/Darwin/osatomics-bitops.mm
new file mode 100644
index 0000000..68badb7
--- /dev/null
+++ b/compiler-rt/test/tsan/Darwin/osatomics-bitops.mm
@@ -0,0 +1,34 @@
+// RUN: %clangxx_tsan %s -o %t -framework Foundation -std=c++11
+// RUN: %run %t 2>&1 | FileCheck %s
+
+#import <Foundation/Foundation.h>
+#import <libkern/OSAtomic.h>
+
+int main(int argc, const char *argv[]) {
+  int value = 1;
+  bool ret = OSAtomicTestAndClear(7, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 0, ret = 1
+
+  ret = OSAtomicTestAndSet(4, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 8, ret = 0
+
+  ret = OSAtomicTestAndClear(4, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 0, ret = 1
+
+  ret = OSAtomicTestAndSet(12, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 2048, ret = 0
+
+  ret = OSAtomicTestAndSet(13, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 3072, ret = 0
+
+  ret = OSAtomicTestAndClear(12, &value);
+  fprintf(stderr, "value = %d, ret = %d\n", value, ret);
+  // CHECK: value = 1024, ret = 1
+
+  return 0;
+}