[asan] GET_CALLER_PC macro for Win. Patch by timurrrr@google.com

llvm-svn: 149994

compiler-rt/lib/asan/asan_internal.h

@@ -212,12 +212,16 @@ const size_t kPageSizeBits = 12;
 const size_t kPageSize = 1UL << kPageSizeBits;
 
 #ifndef _WIN32
-#define GET_CALLER_PC() (uintptr_t)__builtin_return_address(0)
-#define GET_CURRENT_FRAME() (uintptr_t)__builtin_frame_address(0)
+# define GET_CALLER_PC() (uintptr_t)__builtin_return_address(0)
+# define GET_CURRENT_FRAME() (uintptr_t)__builtin_frame_address(0)
 #else
-// TODO(timurrrr): implement.
-#define GET_CALLER_PC() (uintptr_t)0
-#define GET_CURRENT_FRAME() (uintptr_t)0
+extern "C" void* _ReturnAddress(void);
+# pragma intrinsic(_ReturnAddress)
+# define GET_CALLER_PC() (uintptr_t)_ReturnAddress()
+// CaptureStackBackTrace doesn't need to know BP on Windows.
+// FIXME: This macro is still used when printing error reports though it's not
+// clear if the BP value is needed in the ASan reports on Windows.
+# define GET_CURRENT_FRAME() (uintptr_t)0xDEADBEEF
 #endif
 
 #define GET_BP_PC_SP \