[ASan] Add ASan debugging API to get malloc/free stack traces and shadow memory mapping info

Reviewed at http://reviews.llvm.org/D4466

llvm-svn: 213080

1 files changed, 74 insertions, 0 deletions

diff --git a/compiler-rt/lib/asan/asan_debugging.cc b/compiler-rt/lib/asan/asan_debugging.cc
new file mode 100644
index 00000000000..05198a78703
--- /dev/null
+++ b/compiler-rt/lib/asan/asan_debugging.cc
@@ -0,0 +1,74 @@
+//===-- asan_debugging.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 AddressSanitizer, an address sanity checker.
+//
+// This file contains various functions that are generally useful to call when
+// using a debugger (LLDB, GDB).
+//===----------------------------------------------------------------------===//
+
+#include "asan_allocator.h"
+#include "asan_flags.h"
+#include "asan_internal.h"
+#include "asan_mapping.h"
+#include "asan_thread.h"
+
+namespace __asan {
+
+uptr AsanGetStack(uptr addr, uptr *trace, uptr size, u32 *thread_id,
+                  bool alloc_stack) {
+  AsanChunkView chunk = FindHeapChunkByAddress(addr);
+  if (!chunk.IsValid()) return 0;
+
+  StackTrace stack;
+  if (alloc_stack) {
+    if (chunk.AllocTid() == kInvalidTid) return 0;
+    chunk.GetAllocStack(&stack);
+    if (thread_id) *thread_id = chunk.AllocTid();
+  } else {
+    if (chunk.FreeTid() == kInvalidTid) return 0;
+    chunk.GetFreeStack(&stack);
+    if (thread_id) *thread_id = chunk.FreeTid();
+  }
+
+  if (trace && size) {
+    if (size > kStackTraceMax)
+      size = kStackTraceMax;
+    if (size > stack.size)
+      size = stack.size;
+    for (uptr i = 0; i < size; i++)
+      trace[i] = StackTrace::GetPreviousInstructionPc(stack.trace[i]);
+
+    return size;
+  }
+
+  return 0;
+}
+
+}  // namespace __asan
+
+using namespace __asan;
+
+SANITIZER_INTERFACE_ATTRIBUTE
+uptr __asan_get_alloc_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) {
+  return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ true);
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+uptr __asan_get_free_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) {
+  return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ false);
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __asan_get_shadow_mapping(uptr *shadow_scale, uptr *shadow_offset) {
+  if (shadow_scale)
+    *shadow_scale = SHADOW_SCALE;
+  if (shadow_offset)
+    *shadow_offset = SHADOW_OFFSET;
+}