[asan] move FakeStack into a separate file

llvm-svn: 169734

4 files changed, 218 insertions, 190 deletions

diff --git a/compiler-rt/lib/asan/CMakeLists.txt b/compiler-rt/lib/asan/CMakeLists.txt
index 57a6c9a9c37..0f561e6cb6c 100644
--- a/compiler-rt/lib/asan/CMakeLists.txt
+++ b/compiler-rt/lib/asan/CMakeLists.txt
@@ -3,6 +3,7 @@
 set(ASAN_SOURCES
   asan_allocator.cc
   asan_allocator2.cc
+  asan_fake_stack.cc
   asan_globals.cc
   asan_interceptors.cc
   asan_linux.cc
diff --git a/compiler-rt/lib/asan/asan_allocator.cc b/compiler-rt/lib/asan/asan_allocator.cc
index 66c2aa2106c..4d422a7a9ac 100644
--- a/compiler-rt/lib/asan/asan_allocator.cc
+++ b/compiler-rt/lib/asan/asan_allocator.cc
@@ -65,37 +65,6 @@ static inline bool IsAligned(uptr a, uptr alignment) {
   return (a & (alignment - 1)) == 0;
 }
 
-static inline uptr Log2(uptr x) {
-  CHECK(IsPowerOfTwo(x));
-#if !defined(_WIN32) || defined(__clang__)
-  return __builtin_ctzl(x);
-#elif defined(_WIN64)
-  unsigned long ret;  // NOLINT
-  _BitScanForward64(&ret, x);
-  return ret;
-#else
-  unsigned long ret;  // NOLINT
-  _BitScanForward(&ret, x);
-  return ret;
-#endif
-}
-
-static inline uptr RoundUpToPowerOfTwo(uptr size) {
-  CHECK(size);
-  if (IsPowerOfTwo(size)) return size;
-
-  unsigned long up;  // NOLINT
-#if !defined(_WIN32) || defined(__clang__)
-  up = SANITIZER_WORDSIZE - 1 - __builtin_clzl(size);
-#elif defined(_WIN64)
-  _BitScanReverse64(&up, size);
-#else
-  _BitScanReverse(&up, size);
-#endif
-  CHECK(size < (1ULL << (up + 1)));
-  CHECK(size > (1ULL << up));
-  return 1UL << (up + 1);
-}
 
 static inline uptr SizeClassToSize(u8 size_class) {
   CHECK(size_class < kNumberOfSizeClasses);
@@ -865,170 +834,11 @@ void asan_mz_force_unlock() {
   malloc_info.ForceUnlock();
 }
 
-// ---------------------- Fake stack-------------------- {{{1
-FakeStack::FakeStack() {
-  CHECK(REAL(memset) != 0);
-  REAL(memset)(this, 0, sizeof(*this));
-}
-
-bool FakeStack::AddrIsInSizeClass(uptr addr, uptr size_class) {
-  uptr mem = allocated_size_classes_[size_class];
-  uptr size = ClassMmapSize(size_class);
-  bool res = mem && addr >= mem && addr < mem + size;
-  return res;
-}
-
-uptr FakeStack::AddrIsInFakeStack(uptr addr) {
-  for (uptr i = 0; i < kNumberOfSizeClasses; i++) {
-    if (AddrIsInSizeClass(addr, i)) return allocated_size_classes_[i];
-  }
-  return 0;
-}
-
-// We may want to compute this during compilation.
-inline uptr FakeStack::ComputeSizeClass(uptr alloc_size) {
-  uptr rounded_size = RoundUpToPowerOfTwo(alloc_size);
-  uptr log = Log2(rounded_size);
-  CHECK(alloc_size <= (1UL << log));
-  if (!(alloc_size > (1UL << (log-1)))) {
-    Printf("alloc_size %zu log %zu\n", alloc_size, log);
-  }
-  CHECK(alloc_size > (1UL << (log-1)));
-  uptr res = log < kMinStackFrameSizeLog ? 0 : log - kMinStackFrameSizeLog;
-  CHECK(res < kNumberOfSizeClasses);
-  CHECK(ClassSize(res) >= rounded_size);
-  return res;
-}
-
-void FakeFrameFifo::FifoPush(FakeFrame *node) {
-  CHECK(node);
-  node->next = 0;
-  if (first_ == 0 && last_ == 0) {
-    first_ = last_ = node;
-  } else {
-    CHECK(first_);
-    CHECK(last_);
-    last_->next = node;
-    last_ = node;
-  }
-}
-
-FakeFrame *FakeFrameFifo::FifoPop() {
-  CHECK(first_ && last_ && "Exhausted fake stack");
-  FakeFrame *res = 0;
-  if (first_ == last_) {
-    res = first_;
-    first_ = last_ = 0;
-  } else {
-    res = first_;
-    first_ = first_->next;
-  }
-  return res;
-}
-
-void FakeStack::Init(uptr stack_size) {
-  stack_size_ = stack_size;
-  alive_ = true;
-}
-
-void FakeStack::Cleanup() {
-  alive_ = false;
-  for (uptr i = 0; i < kNumberOfSizeClasses; i++) {
-    uptr mem = allocated_size_classes_[i];
-    if (mem) {
-      PoisonShadow(mem, ClassMmapSize(i), 0);
-      allocated_size_classes_[i] = 0;
-      UnmapOrDie((void*)mem, ClassMmapSize(i));
-    }
-  }
-}
-
-uptr FakeStack::ClassMmapSize(uptr size_class) {
-  return RoundUpToPowerOfTwo(stack_size_);
-}
-
-void FakeStack::AllocateOneSizeClass(uptr size_class) {
-  CHECK(ClassMmapSize(size_class) >= GetPageSizeCached());
-  uptr new_mem = (uptr)MmapOrDie(
-      ClassMmapSize(size_class), __FUNCTION__);
-  // Printf("T%d new_mem[%zu]: %p-%p mmap %zu\n",
-  //       asanThreadRegistry().GetCurrent()->tid(),
-  //       size_class, new_mem, new_mem + ClassMmapSize(size_class),
-  //       ClassMmapSize(size_class));
-  uptr i;
-  for (i = 0; i < ClassMmapSize(size_class);
-       i += ClassSize(size_class)) {
-    size_classes_[size_class].FifoPush((FakeFrame*)(new_mem + i));
-  }
-  CHECK(i == ClassMmapSize(size_class));
-  allocated_size_classes_[size_class] = new_mem;
-}
-
-uptr FakeStack::AllocateStack(uptr size, uptr real_stack) {
-  if (!alive_) return real_stack;
-  CHECK(size <= kMaxStackMallocSize && size > 1);
-  uptr size_class = ComputeSizeClass(size);
-  if (!allocated_size_classes_[size_class]) {
-    AllocateOneSizeClass(size_class);
-  }
-  FakeFrame *fake_frame = size_classes_[size_class].FifoPop();
-  CHECK(fake_frame);
-  fake_frame->size_minus_one = size - 1;
-  fake_frame->real_stack = real_stack;
-  while (FakeFrame *top = call_stack_.top()) {
-    if (top->real_stack > real_stack) break;
-    call_stack_.LifoPop();
-    DeallocateFrame(top);
-  }
-  call_stack_.LifoPush(fake_frame);
-  uptr ptr = (uptr)fake_frame;
-  PoisonShadow(ptr, size, 0);
-  return ptr;
-}
-
-void FakeStack::DeallocateFrame(FakeFrame *fake_frame) {
-  CHECK(alive_);
-  uptr size = fake_frame->size_minus_one + 1;
-  uptr size_class = ComputeSizeClass(size);
-  CHECK(allocated_size_classes_[size_class]);
-  uptr ptr = (uptr)fake_frame;
-  CHECK(AddrIsInSizeClass(ptr, size_class));
-  CHECK(AddrIsInSizeClass(ptr + size - 1, size_class));
-  size_classes_[size_class].FifoPush(fake_frame);
-}
-
-void FakeStack::OnFree(uptr ptr, uptr size, uptr real_stack) {
-  FakeFrame *fake_frame = (FakeFrame*)ptr;
-  CHECK(fake_frame->magic = kRetiredStackFrameMagic);
-  CHECK(fake_frame->descr != 0);
-  CHECK(fake_frame->size_minus_one == size - 1);
-  PoisonShadow(ptr, size, kAsanStackAfterReturnMagic);
-}
-
 }  // namespace __asan
 
 // ---------------------- Interface ---------------- {{{1
 using namespace __asan;  // NOLINT
 
-uptr __asan_stack_malloc(uptr size, uptr real_stack) {
-  if (!flags()->use_fake_stack) return real_stack;
-  AsanThread *t = asanThreadRegistry().GetCurrent();
-  if (!t) {
-    // TSD is gone, use the real stack.
-    return real_stack;
-  }
-  uptr ptr = t->fake_stack().AllocateStack(size, real_stack);
-  // Printf("__asan_stack_malloc %p %zu %p\n", ptr, size, real_stack);
-  return ptr;
-}
-
-void __asan_stack_free(uptr ptr, uptr size, uptr real_stack) {
-  if (!flags()->use_fake_stack) return;
-  if (ptr != real_stack) {
-    FakeStack::OnFree(ptr, size, real_stack);
-  }
-}
-
 // ASan allocator doesn't reserve extra bytes, so normally we would
 // just return "size".
 uptr __asan_get_estimated_allocated_size(uptr size) {
diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index 803aa239275..1e936c3054a 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -181,5 +181,40 @@ uptr asan_mz_size(const void *ptr);
 void asan_mz_force_lock();
 void asan_mz_force_unlock();
 
+// Log2 and RoundUpToPowerOfTwo should be inlined for performance.
+
+static inline uptr Log2(uptr x) {
+  CHECK(IsPowerOfTwo(x));
+#if !defined(_WIN32) || defined(__clang__)
+  return __builtin_ctzl(x);
+#elif defined(_WIN64)
+  unsigned long ret;  // NOLINT
+  _BitScanForward64(&ret, x);
+  return ret;
+#else
+  unsigned long ret;  // NOLINT
+  _BitScanForward(&ret, x);
+  return ret;
+#endif
+}
+
+static inline uptr RoundUpToPowerOfTwo(uptr size) {
+  CHECK(size);
+  if (IsPowerOfTwo(size)) return size;
+
+  unsigned long up;  // NOLINT
+#if !defined(_WIN32) || defined(__clang__)
+  up = SANITIZER_WORDSIZE - 1 - __builtin_clzl(size);
+#elif defined(_WIN64)
+  _BitScanReverse64(&up, size);
+#else
+  _BitScanReverse(&up, size);
+#endif
+  CHECK(size < (1ULL << (up + 1)));
+  CHECK(size > (1ULL << up));
+  return 1UL << (up + 1);
+}
+
+
 }  // namespace __asan
 #endif  // ASAN_ALLOCATOR_H
diff --git a/compiler-rt/lib/asan/asan_fake_stack.cc b/compiler-rt/lib/asan/asan_fake_stack.cc
new file mode 100644
index 00000000000..7c5a16312d4
--- /dev/null
+++ b/compiler-rt/lib/asan/asan_fake_stack.cc
@@ -0,0 +1,182 @@
+//===-- asan_fake_stack.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.
+//
+// FakeStack is used to detect use-after-return bugs.
+//===----------------------------------------------------------------------===//
+#include "asan_allocator.h"
+#include "asan_thread.h"
+#include "asan_thread_registry.h"
+#include "sanitizer/asan_interface.h"
+
+namespace __asan {
+
+FakeStack::FakeStack() {
+  CHECK(REAL(memset) != 0);
+  REAL(memset)(this, 0, sizeof(*this));
+}
+
+bool FakeStack::AddrIsInSizeClass(uptr addr, uptr size_class) {
+  uptr mem = allocated_size_classes_[size_class];
+  uptr size = ClassMmapSize(size_class);
+  bool res = mem && addr >= mem && addr < mem + size;
+  return res;
+}
+
+uptr FakeStack::AddrIsInFakeStack(uptr addr) {
+  for (uptr i = 0; i < kNumberOfSizeClasses; i++) {
+    if (AddrIsInSizeClass(addr, i)) return allocated_size_classes_[i];
+  }
+  return 0;
+}
+
+// We may want to compute this during compilation.
+inline uptr FakeStack::ComputeSizeClass(uptr alloc_size) {
+  uptr rounded_size = RoundUpToPowerOfTwo(alloc_size);
+  uptr log = Log2(rounded_size);
+  CHECK(alloc_size <= (1UL << log));
+  if (!(alloc_size > (1UL << (log-1)))) {
+    Printf("alloc_size %zu log %zu\n", alloc_size, log);
+  }
+  CHECK(alloc_size > (1UL << (log-1)));
+  uptr res = log < kMinStackFrameSizeLog ? 0 : log - kMinStackFrameSizeLog;
+  CHECK(res < kNumberOfSizeClasses);
+  CHECK(ClassSize(res) >= rounded_size);
+  return res;
+}
+
+void FakeFrameFifo::FifoPush(FakeFrame *node) {
+  CHECK(node);
+  node->next = 0;
+  if (first_ == 0 && last_ == 0) {
+    first_ = last_ = node;
+  } else {
+    CHECK(first_);
+    CHECK(last_);
+    last_->next = node;
+    last_ = node;
+  }
+}
+
+FakeFrame *FakeFrameFifo::FifoPop() {
+  CHECK(first_ && last_ && "Exhausted fake stack");
+  FakeFrame *res = 0;
+  if (first_ == last_) {
+    res = first_;
+    first_ = last_ = 0;
+  } else {
+    res = first_;
+    first_ = first_->next;
+  }
+  return res;
+}
+
+void FakeStack::Init(uptr stack_size) {
+  stack_size_ = stack_size;
+  alive_ = true;
+}
+
+void FakeStack::Cleanup() {
+  alive_ = false;
+  for (uptr i = 0; i < kNumberOfSizeClasses; i++) {
+    uptr mem = allocated_size_classes_[i];
+    if (mem) {
+      PoisonShadow(mem, ClassMmapSize(i), 0);
+      allocated_size_classes_[i] = 0;
+      UnmapOrDie((void*)mem, ClassMmapSize(i));
+    }
+  }
+}
+
+uptr FakeStack::ClassMmapSize(uptr size_class) {
+  return RoundUpToPowerOfTwo(stack_size_);
+}
+
+void FakeStack::AllocateOneSizeClass(uptr size_class) {
+  CHECK(ClassMmapSize(size_class) >= GetPageSizeCached());
+  uptr new_mem = (uptr)MmapOrDie(
+      ClassMmapSize(size_class), __FUNCTION__);
+  // Printf("T%d new_mem[%zu]: %p-%p mmap %zu\n",
+  //       asanThreadRegistry().GetCurrent()->tid(),
+  //       size_class, new_mem, new_mem + ClassMmapSize(size_class),
+  //       ClassMmapSize(size_class));
+  uptr i;
+  for (i = 0; i < ClassMmapSize(size_class);
+       i += ClassSize(size_class)) {
+    size_classes_[size_class].FifoPush((FakeFrame*)(new_mem + i));
+  }
+  CHECK(i == ClassMmapSize(size_class));
+  allocated_size_classes_[size_class] = new_mem;
+}
+
+uptr FakeStack::AllocateStack(uptr size, uptr real_stack) {
+  if (!alive_) return real_stack;
+  CHECK(size <= kMaxStackMallocSize && size > 1);
+  uptr size_class = ComputeSizeClass(size);
+  if (!allocated_size_classes_[size_class]) {
+    AllocateOneSizeClass(size_class);
+  }
+  FakeFrame *fake_frame = size_classes_[size_class].FifoPop();
+  CHECK(fake_frame);
+  fake_frame->size_minus_one = size - 1;
+  fake_frame->real_stack = real_stack;
+  while (FakeFrame *top = call_stack_.top()) {
+    if (top->real_stack > real_stack) break;
+    call_stack_.LifoPop();
+    DeallocateFrame(top);
+  }
+  call_stack_.LifoPush(fake_frame);
+  uptr ptr = (uptr)fake_frame;
+  PoisonShadow(ptr, size, 0);
+  return ptr;
+}
+
+void FakeStack::DeallocateFrame(FakeFrame *fake_frame) {
+  CHECK(alive_);
+  uptr size = fake_frame->size_minus_one + 1;
+  uptr size_class = ComputeSizeClass(size);
+  CHECK(allocated_size_classes_[size_class]);
+  uptr ptr = (uptr)fake_frame;
+  CHECK(AddrIsInSizeClass(ptr, size_class));
+  CHECK(AddrIsInSizeClass(ptr + size - 1, size_class));
+  size_classes_[size_class].FifoPush(fake_frame);
+}
+
+void FakeStack::OnFree(uptr ptr, uptr size, uptr real_stack) {
+  FakeFrame *fake_frame = (FakeFrame*)ptr;
+  CHECK(fake_frame->magic = kRetiredStackFrameMagic);
+  CHECK(fake_frame->descr != 0);
+  CHECK(fake_frame->size_minus_one == size - 1);
+  PoisonShadow(ptr, size, kAsanStackAfterReturnMagic);
+}
+
+}  // namespace __asan
+
+// ---------------------- Interface ---------------- {{{1
+using namespace __asan;  // NOLINT
+
+uptr __asan_stack_malloc(uptr size, uptr real_stack) {
+  if (!flags()->use_fake_stack) return real_stack;
+  AsanThread *t = asanThreadRegistry().GetCurrent();
+  if (!t) {
+    // TSD is gone, use the real stack.
+    return real_stack;
+  }
+  uptr ptr = t->fake_stack().AllocateStack(size, real_stack);
+  // Printf("__asan_stack_malloc %p %zu %p\n", ptr, size, real_stack);
+  return ptr;
+}
+
+void __asan_stack_free(uptr ptr, uptr size, uptr real_stack) {
+  if (!flags()->use_fake_stack) return;
+  if (ptr != real_stack) {
+    FakeStack::OnFree(ptr, size, real_stack);
+  }
+}