[Sanitizer] Add a test for the fast unwinder

Summary:
The test sets up fake x86-style fp+retaddr frames, since that's all the
unwinder works with.

Reviewers: kcc

CC: eugenis
Differential Revision: http://llvm-reviews.chandlerc.com/D445

llvm-svn: 175893

diff --git a/compiler-rt/lib/sanitizer_common/tests/CMakeLists.txt b/compiler-rt/lib/sanitizer_common/tests/CMakeLists.txt
index c6ab996..41a0bf1 100644 (file)
--- a/compiler-rt/lib/sanitizer_common/tests/CMakeLists.txt
+++ b/compiler-rt/lib/sanitizer_common/tests/CMakeLists.txt
@@ -10,6 +10,7 @@ set(SANITIZER_UNITTESTS
   sanitizer_printf_test.cc
   sanitizer_scanf_interceptor_test.cc
   sanitizer_stackdepot_test.cc
+  sanitizer_stacktrace_test.cc
   sanitizer_test_main.cc
   )
 

diff --git a/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cc b/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cc
new file mode 100644 (file)
index 0000000..2a2cfe6
--- /dev/null
+++ b/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cc
@@ -0,0 +1,78 @@
+//===-- sanitizer_stacktrace_test.cc --------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer/AddressSanitizer runtime.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_stacktrace.h"
+#include "gtest/gtest.h"
+
+namespace __sanitizer {
+
+class FastUnwindTest : public ::testing::Test {
+ protected:
+  virtual void SetUp();
+
+  uptr fake_stack[10];
+  uptr start_pc;
+  uptr fake_top;
+  uptr fake_bottom;
+  StackTrace trace;
+};
+
+void FastUnwindTest::SetUp() {
+  // Fill an array of pointers with fake fp+retaddr pairs.  Frame pointers have
+  // even indices.
+  for (int i = 0; i+1 < ARRAY_SIZE(fake_stack); i += 2) {
+    fake_stack[i] = (uptr)&fake_stack[i+2];  // fp
+    fake_stack[i+1] = i+1; // retaddr
+  }
+  // Mark the last fp as zero to terminate the stack trace.
+  fake_stack[RoundDownTo(ARRAY_SIZE(fake_stack) - 1, 2)] = 0;
+
+  // Top is two slots past the end because FastUnwindStack subtracts two.
+  fake_top = (uptr)&fake_stack[ARRAY_SIZE(fake_stack) + 2];
+  // Bottom is one slot before the start because FastUnwindStack uses >.
+  fake_bottom = (uptr)&fake_stack[-1];
+  start_pc = 0;
+
+  // This is common setup done by __asan::GetStackTrace().
+  trace.size = 0;
+  trace.max_size = ARRAY_SIZE(fake_stack);
+  trace.trace[0] = start_pc;
+}
+
+TEST_F(FastUnwindTest, Basic) {
+  trace.FastUnwindStack(start_pc, (uptr)&fake_stack[0],
+                        fake_top, fake_bottom);
+  // Should get all on-stack retaddrs and start_pc.
+  EXPECT_EQ(6, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (int i = 1; i <= 5; i++) {
+    EXPECT_EQ(i*2 - 1, trace.trace[i]);
+  }
+}
+
+// From: http://code.google.com/p/address-sanitizer/issues/detail?id=162
+TEST_F(FastUnwindTest, FramePointerLoop) {
+  // Make one fp point to itself.
+  fake_stack[4] = (uptr)&fake_stack[4];
+  trace.FastUnwindStack(start_pc, (uptr)&fake_stack[0],
+                        fake_top, fake_bottom);
+  // Should get all on-stack retaddrs up to the 4th slot and start_pc.
+  EXPECT_EQ(4, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (int i = 1; i <= 3; i++) {
+    EXPECT_EQ(i*2 - 1, trace.trace[i]);
+  }
+}
+
+}  // namespace __sanitizer