1 files changed, 163 insertions, 0 deletions
diff --git a/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cpp b/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cpp
new file mode 100644
index 00000000000..afd4a0eca62
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+++ b/compiler-rt/lib/sanitizer_common/tests/sanitizer_stacktrace_test.cpp
@@ -0,0 +1,163 @@
+//===-- sanitizer_stacktrace_test.cpp -------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// 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();
+  virtual void TearDown();
+
+  void UnwindFast();
+
+  void *mapping;
+  uhwptr *fake_stack;
+  const uptr fake_stack_size = 10;
+  uhwptr start_pc;
+
+  uhwptr fake_bp;
+  uhwptr fake_top;
+  uhwptr fake_bottom;
+  BufferedStackTrace trace;
+};
+
+static uptr PC(uptr idx) {
+  return (1<<20) + idx;
+}
+
+void FastUnwindTest::SetUp() {
+  size_t ps = GetPageSize();
+  mapping = MmapOrDie(2 * ps, "FastUnwindTest");
+  MprotectNoAccess((uptr)mapping, ps);
+
+  // Unwinder may peek 1 word down from the starting FP.
+  fake_stack = (uhwptr *)((uptr)mapping + ps + sizeof(uhwptr));
+
+  // Fill an array of pointers with fake fp+retaddr pairs.  Frame pointers have
+  // even indices.
+  for (uptr i = 0; i + 1 < fake_stack_size; i += 2) {
+    fake_stack[i] = (uptr)&fake_stack[i+2];  // fp
+    fake_stack[i+1] = PC(i + 1); // retaddr
+  }
+  // Mark the last fp point back up to terminate the stack trace.
+  fake_stack[RoundDownTo(fake_stack_size - 1, 2)] = (uhwptr)&fake_stack[0];
+
+  // Top is two slots past the end because UnwindFast subtracts two.
+  fake_top = (uhwptr)&fake_stack[fake_stack_size + 2];
+  // Bottom is one slot before the start because UnwindFast uses >.
+  fake_bottom = (uhwptr)mapping;
+  fake_bp = (uptr)&fake_stack[0];
+  start_pc = PC(0);
+}
+
+void FastUnwindTest::TearDown() {
+  size_t ps = GetPageSize();
+  UnmapOrDie(mapping, 2 * ps);
+}
+
+#if SANITIZER_CAN_FAST_UNWIND
+
+void FastUnwindTest::UnwindFast() {
+  trace.UnwindFast(start_pc, fake_bp, fake_top, fake_bottom, kStackTraceMax);
+}
+
+TEST_F(FastUnwindTest, Basic) {
+  UnwindFast();
+  // Should get all on-stack retaddrs and start_pc.
+  EXPECT_EQ(6U, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (uptr i = 1; i <= 5; i++) {
+    EXPECT_EQ(PC(i*2 - 1), trace.trace[i]);
+  }
+}
+
+// From: https://github.com/google/sanitizers/issues/162
+TEST_F(FastUnwindTest, FramePointerLoop) {
+  // Make one fp point to itself.
+  fake_stack[4] = (uhwptr)&fake_stack[4];
+  UnwindFast();
+  // Should get all on-stack retaddrs up to the 4th slot and start_pc.
+  EXPECT_EQ(4U, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (uptr i = 1; i <= 3; i++) {
+    EXPECT_EQ(PC(i*2 - 1), trace.trace[i]);
+  }
+}
+
+TEST_F(FastUnwindTest, MisalignedFramePointer) {
+  // Make one fp misaligned.
+  fake_stack[4] += 3;
+  UnwindFast();
+  // Should get all on-stack retaddrs up to the 4th slot and start_pc.
+  EXPECT_EQ(4U, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (uptr i = 1; i < 4U; i++) {
+    EXPECT_EQ(PC(i*2 - 1), trace.trace[i]);
+  }
+}
+
+TEST_F(FastUnwindTest, OneFrameStackTrace) {
+  trace.Unwind(start_pc, fake_bp, nullptr, true, 1);
+  EXPECT_EQ(1U, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  EXPECT_EQ((uhwptr)&fake_stack[0], trace.top_frame_bp);
+}
+
+TEST_F(FastUnwindTest, ZeroFramesStackTrace) {
+  trace.Unwind(start_pc, fake_bp, nullptr, true, 0);
+  EXPECT_EQ(0U, trace.size);
+  EXPECT_EQ(0U, trace.top_frame_bp);
+}
+
+TEST_F(FastUnwindTest, FPBelowPrevFP) {
+  // The next FP points to unreadable memory inside the stack limits, but below
+  // current FP.
+  fake_stack[0] = (uhwptr)&fake_stack[-50];
+  fake_stack[1] = PC(1);
+  UnwindFast();
+  EXPECT_EQ(2U, trace.size);
+  EXPECT_EQ(PC(0), trace.trace[0]);
+  EXPECT_EQ(PC(1), trace.trace[1]);
+}
+
+TEST_F(FastUnwindTest, CloseToZeroFrame) {
+  // Make one pc a NULL pointer.
+  fake_stack[5] = 0x0;
+  UnwindFast();
+  // The stack should be truncated at the NULL pointer (and not include it).
+  EXPECT_EQ(3U, trace.size);
+  EXPECT_EQ(start_pc, trace.trace[0]);
+  for (uptr i = 1; i < 3U; i++) {
+    EXPECT_EQ(PC(i*2 - 1), trace.trace[i]);
+  }
+}
+
+#endif // SANITIZER_CAN_FAST_UNWIND
+
+TEST(SlowUnwindTest, ShortStackTrace) {
+  BufferedStackTrace stack;
+  uptr pc = StackTrace::GetCurrentPc();
+  uptr bp = GET_CURRENT_FRAME();
+  stack.Unwind(pc, bp, nullptr, false, /*max_depth=*/0);
+  EXPECT_EQ(0U, stack.size);
+  EXPECT_EQ(0U, stack.top_frame_bp);
+  stack.Unwind(pc, bp, nullptr, false, /*max_depth=*/1);
+  EXPECT_EQ(1U, stack.size);
+  EXPECT_EQ(pc, stack.trace[0]);
+  EXPECT_EQ(bp, stack.top_frame_bp);
+}
+
+}  // namespace __sanitizer