[tsan] Add support for C++ exceptions into TSan (call __tsan_func_exit during unwinding), LLVM part
This adds support for TSan C++ exception handling, where we need to add extra calls to __tsan_func_exit when a function is exitted via exception mechanisms. Otherwise the shadow stack gets corrupted (leaked). This patch moves and enhances the existing implementation of EscapeEnumerator that finds all possible function exit points, and adds extra EH cleanup blocks where needed.
Differential Revision: https://reviews.llvm.org/D26177
llvm-svn: 286893
diff --git a/llvm/test/Instrumentation/ThreadSanitizer/eh.ll b/llvm/test/Instrumentation/ThreadSanitizer/eh.ll
new file mode 100644
index 0000000..a9a54b6
--- /dev/null
+++ b/llvm/test/Instrumentation/ThreadSanitizer/eh.ll
@@ -0,0 +1,57 @@
+; RUN: opt < %s -tsan -S | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-EXC
+; RUN: opt < %s -tsan -S -tsan-handle-cxx-exceptions=0 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-NOEXC
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+declare void @can_throw()
+declare void @cannot_throw() nounwind
+
+define i32 @func1() sanitize_thread {
+ call void @can_throw()
+ ret i32 0
+ ; CHECK-EXC: define i32 @func1()
+ ; CHECK-EXC: call void @__tsan_func_entry
+ ; CHECK-EXC: invoke void @can_throw()
+ ; CHECK-EXC: .noexc:
+ ; CHECK-EXC: call void @__tsan_func_exit()
+ ; CHECK-EXC: ret i32 0
+ ; CHECK-EXC: tsan_cleanup:
+ ; CHECK-EXC: call void @__tsan_func_exit()
+ ; CHECK-EXC: resume
+ ; CHECK-NOEXC: define i32 @func1()
+ ; CHECK-NOEXC: call void @__tsan_func_entry
+ ; CHECK-NOEXC: call void @can_throw()
+ ; CHECK-NOEXC: call void @__tsan_func_exit()
+ ; CHECK-NOEXC: ret i32 0
+}
+
+define i32 @func2() sanitize_thread {
+ call void @cannot_throw()
+ ret i32 0
+ ; CHECK: define i32 @func2()
+ ; CHECK: call void @__tsan_func_entry
+ ; CHECK: call void @cannot_throw()
+ ; CHECK: call void @__tsan_func_exit()
+ ; CHECK: ret i32 0
+}
+
+define i32 @func3(i32* %p) sanitize_thread {
+ %a = load i32, i32* %p
+ ret i32 %a
+ ; CHECK: define i32 @func3(i32* %p)
+ ; CHECK: call void @__tsan_func_entry
+ ; CHECK: call void @__tsan_read4
+ ; CHECK: %a = load i32, i32* %p
+ ; CHECK: call void @__tsan_func_exit()
+ ; CHECK: ret i32 %a
+}
+
+define i32 @func4() sanitize_thread nounwind {
+ call void @can_throw()
+ ret i32 0
+ ; CHECK: define i32 @func4()
+ ; CHECK: call void @__tsan_func_entry
+ ; CHECK: call void @can_throw()
+ ; CHECK: call void @__tsan_func_exit()
+ ; CHECK: ret i32 0
+}