diff options
| -rw-r--r-- | absl/debugging/internal/stacktrace_riscv-inl.inc | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/absl/debugging/internal/stacktrace_riscv-inl.inc b/absl/debugging/internal/stacktrace_riscv-inl.inc index 98b09a22..7123b71b 100644 --- a/absl/debugging/internal/stacktrace_riscv-inl.inc +++ b/absl/debugging/internal/stacktrace_riscv-inl.inc @@ -171,26 +171,21 @@ ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS // May read random elements from stack. ABSL_ATTRIBUTE_NO_SANITIZE_MEMORY // May read random elements from stack. static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count, const void *ucp, int *min_dropped_frames) { + // The `frame_pointer` that is computed here points to the top of the frame. + // The two words preceding the address are the return address and the previous + // frame pointer. #if defined(__GNUC__) void **frame_pointer = reinterpret_cast<void **>(__builtin_frame_address(0)); #else #error reading stack pointer not yet supported on this platform #endif - skip_count++; // Skip the frame for this function. int n = 0; - - // The `frame_pointer` that is computed here points to the top of the frame. - // The two words preceding the address are the return address and the previous - // frame pointer. To find a PC value associated with the current frame, we - // need to go down a level in the call chain. So we remember the return - // address of the last frame seen. This does not work for the first stack - // frame, which belongs to `UnwindImp()` but we skip the frame for - // `UnwindImp()` anyway. - void *prev_return_address = nullptr; - + void *return_address = nullptr; while (frame_pointer && n < max_depth) { - // The absl::GetStackFrames routine si called when we are in some + return_address = frame_pointer[-1]; + + // The absl::GetStackFrames routine is called when we are in some // informational context (the failure signal handler for example). Use the // non-strict unwinding rules to produce a stack trace that is as complete // as possible (even if it contains a few bogus entries in some rare cases). @@ -200,15 +195,16 @@ static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count, if (skip_count > 0) { skip_count--; } else { - result[n] = prev_return_address; + result[n] = return_address; if (IS_STACK_FRAMES) { sizes[n] = ComputeStackFrameSize(frame_pointer, next_frame_pointer); } n++; } - prev_return_address = frame_pointer[-1]; + frame_pointer = next_frame_pointer; } + if (min_dropped_frames != nullptr) { // Implementation detail: we clamp the max of frames we are willing to // count, so as not to spend too much time in the loop below. @@ -225,6 +221,7 @@ static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count, } *min_dropped_frames = num_dropped_frames; } + return n; } |