[compiler-rt] [llvm] [clang] [NFC, sanitizer_symbolizer] Split Fuchsia and Markup. (PR #72305)

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=?utf-8?q?Andrés?= Villegas <andresvi at google.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/72305 at github.com>


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@@ -0,0 +1,66 @@
+//===------------------ sanitizer_unwind_fuchsia.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
+//
+//===----------------------------------------------------------------------===//
+//
+/// Sanitizer unwind Fuchsia specific functions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+#if SANITIZER_FUCHSIA
+
+#  include <limits.h>
+#  include <unwind.h>
+
+#  include "sanitizer_common.h"
+#  include "sanitizer_stacktrace.h"
+
+namespace __sanitizer {
+
+#  if SANITIZER_CAN_SLOW_UNWIND
+struct UnwindTraceArg {
+  BufferedStackTrace *stack;
+  u32 max_depth;
+};
+
+_Unwind_Reason_Code Unwind_Trace(struct _Unwind_Context *ctx, void *param) {
+  UnwindTraceArg *arg = static_cast<UnwindTraceArg *>(param);
+  CHECK_LT(arg->stack->size, arg->max_depth);
+  uptr pc = _Unwind_GetIP(ctx);
+  if (pc < GetPageSizeCached())
+    return _URC_NORMAL_STOP;
+  arg->stack->trace_buffer[arg->stack->size++] = pc;
+  return (arg->stack->size == arg->max_depth ? _URC_NORMAL_STOP
+                                             : _URC_NO_REASON);
+}
+
+void BufferedStackTrace::UnwindSlow(uptr pc, u32 max_depth) {
+  CHECK_GE(max_depth, 2);
+  size = 0;
+  UnwindTraceArg arg = {this, Min(max_depth + 1, kStackTraceMax)};
+  _Unwind_Backtrace(Unwind_Trace, &arg);
+  CHECK_GT(size, 0);
+  // We need to pop a few frames so that pc is on top.
+  uptr to_pop = LocatePcInTrace(pc);
+  // trace_buffer[0] belongs to the current function so we always pop it,
+  // unless there is only 1 frame in the stack trace (1 frame is always better
+  // than 0!).
+  PopStackFrames(Min(to_pop, static_cast<uptr>(1)));
+  trace_buffer[0] = pc;
+}
+
+void BufferedStackTrace::UnwindSlow(uptr pc, void *context, u32 max_depth) {
+  CHECK(context);
+  CHECK_GE(max_depth, 2);
+  UNREACHABLE("signal context doesn't exist");
+}
+#  endif  //  SANITIZER_CAN_SLOW_UNWIND
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PiJoules wrote:

same here

https://github.com/llvm/llvm-project/pull/72305