1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/security/sandbox/chromium/base/debug/profiler.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,90 @@
1.4 +// Copyright (c) 2012 The Chromium Authors. All rights reserved.
1.5 +// Use of this source code is governed by a BSD-style license that can be
1.6 +// found in the LICENSE file.
1.7 +
1.8 +#ifndef BASE_DEBUG_PROFILER_H
1.9 +#define BASE_DEBUG_PROFILER_H
1.10 +
1.11 +#include <string>
1.12 +
1.13 +#include "base/base_export.h"
1.14 +#include "base/basictypes.h"
1.15 +
1.16 +// The Profiler functions allow usage of the underlying sampling based
1.17 +// profiler. If the application has not been built with the necessary
1.18 +// flags (-DENABLE_PROFILING and not -DNO_TCMALLOC) then these functions
1.19 +// are noops.
1.20 +namespace base {
1.21 +namespace debug {
1.22 +
1.23 +// Start profiling with the supplied name.
1.24 +// {pid} will be replaced by the process' pid and {count} will be replaced
1.25 +// by the count of the profile run (starts at 1 with each process).
1.26 +BASE_EXPORT void StartProfiling(const std::string& name);
1.27 +
1.28 +// Stop profiling and write out data.
1.29 +BASE_EXPORT void StopProfiling();
1.30 +
1.31 +// Force data to be written to file.
1.32 +BASE_EXPORT void FlushProfiling();
1.33 +
1.34 +// Returns true if process is being profiled.
1.35 +BASE_EXPORT bool BeingProfiled();
1.36 +
1.37 +// Reset profiling after a fork, which disables timers.
1.38 +BASE_EXPORT void RestartProfilingAfterFork();
1.39 +
1.40 +// Returns true iff this executable is instrumented with the Syzygy profiler.
1.41 +BASE_EXPORT bool IsBinaryInstrumented();
1.42 +
1.43 +// There's a class of profilers that use "return address swizzling" to get a
1.44 +// hook on function exits. This class of profilers uses some form of entry hook,
1.45 +// like e.g. binary instrumentation, or a compiler flag, that calls a hook each
1.46 +// time a function is invoked. The hook then switches the return address on the
1.47 +// stack for the address of an exit hook function, and pushes the original
1.48 +// return address to a shadow stack of some type. When in due course the CPU
1.49 +// executes a return to the exit hook, the exit hook will do whatever work it
1.50 +// does on function exit, then arrange to return to the original return address.
1.51 +// This class of profiler does not play well with programs that look at the
1.52 +// return address, as does e.g. V8. V8 uses the return address to certain
1.53 +// runtime functions to find the JIT code that called it, and from there finds
1.54 +// the V8 data structures associated to the JS function involved.
1.55 +// A return address resolution function is used to fix this. It allows such
1.56 +// programs to resolve a location on stack where a return address originally
1.57 +// resided, to the shadow stack location where the profiler stashed it.
1.58 +typedef uintptr_t (*ReturnAddressLocationResolver)(
1.59 + uintptr_t return_addr_location);
1.60 +
1.61 +// This type declaration must match V8's FunctionEntryHook.
1.62 +typedef void (*DynamicFunctionEntryHook)(uintptr_t function,
1.63 + uintptr_t return_addr_location);
1.64 +
1.65 +// The functions below here are to support profiling V8-generated code.
1.66 +// V8 has provisions for generating a call to an entry hook for newly generated
1.67 +// JIT code, and it can push symbol information on code generation and advise
1.68 +// when the garbage collector moves code. The functions declarations below here
1.69 +// make glue between V8's facilities and a profiler.
1.70 +
1.71 +// This type declaration must match V8's FunctionEntryHook.
1.72 +typedef void (*DynamicFunctionEntryHook)(uintptr_t function,
1.73 + uintptr_t return_addr_location);
1.74 +
1.75 +typedef void (*AddDynamicSymbol)(const void* address,
1.76 + size_t length,
1.77 + const char* name,
1.78 + size_t name_len);
1.79 +typedef void (*MoveDynamicSymbol)(const void* address, const void* new_address);
1.80 +
1.81 +
1.82 +// If this binary is instrumented and the instrumentation supplies a function
1.83 +// for each of those purposes, find and return the function in question.
1.84 +// Otherwise returns NULL.
1.85 +BASE_EXPORT ReturnAddressLocationResolver GetProfilerReturnAddrResolutionFunc();
1.86 +BASE_EXPORT DynamicFunctionEntryHook GetProfilerDynamicFunctionEntryHookFunc();
1.87 +BASE_EXPORT AddDynamicSymbol GetProfilerAddDynamicSymbolFunc();
1.88 +BASE_EXPORT MoveDynamicSymbol GetProfilerMoveDynamicSymbolFunc();
1.89 +
1.90 +} // namespace debug
1.91 +} // namespace base
1.92 +
1.93 +#endif // BASE_DEBUG_DEBUGGER_H
