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Edit File: test-log-stack-tracer.cc
// Copyright 2011 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // // Tests of profiler-related functions from log.h #include <stdlib.h> #include "v8.h" #include "api.h" #include "codegen.h" #include "log.h" #include "isolate.h" #include "cctest.h" #include "disassembler.h" #include "vm-state-inl.h" using v8::Function; using v8::Local; using v8::Object; using v8::Script; using v8::String; using v8::Value; using v8::internal::byte; using v8::internal::Address; using v8::internal::Handle; using v8::internal::Isolate; using v8::internal::JSFunction; using v8::internal::StackTracer; using v8::internal::TickSample; static v8::Persistent<v8::Context> env; static struct { TickSample* sample; } trace_env = { NULL }; static void InitTraceEnv(TickSample* sample) { trace_env.sample = sample; } static void DoTrace(Address fp) { trace_env.sample->fp = fp; // sp is only used to define stack high bound trace_env.sample->sp = reinterpret_cast<Address>(trace_env.sample) - 10240; StackTracer::Trace(Isolate::Current(), trace_env.sample); } // Hide c_entry_fp to emulate situation when sampling is done while // pure JS code is being executed static void DoTraceHideCEntryFPAddress(Address fp) { v8::internal::Address saved_c_frame_fp = *(Isolate::Current()->c_entry_fp_address()); CHECK(saved_c_frame_fp); *(Isolate::Current()->c_entry_fp_address()) = 0; DoTrace(fp); *(Isolate::Current()->c_entry_fp_address()) = saved_c_frame_fp; } // --- T r a c e E x t e n s i o n --- class TraceExtension : public v8::Extension { public: TraceExtension() : v8::Extension("v8/trace", kSource) { } virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction( v8::Handle<String> name); static v8::Handle<v8::Value> Trace(const v8::Arguments& args); static v8::Handle<v8::Value> JSTrace(const v8::Arguments& args); static v8::Handle<v8::Value> JSEntrySP(const v8::Arguments& args); static v8::Handle<v8::Value> JSEntrySPLevel2(const v8::Arguments& args); private: static Address GetFP(const v8::Arguments& args); static const char* kSource; }; const char* TraceExtension::kSource = "native function trace();" "native function js_trace();" "native function js_entry_sp();" "native function js_entry_sp_level2();"; v8::Handle<v8::FunctionTemplate> TraceExtension::GetNativeFunction( v8::Handle<String> name) { if (name->Equals(String::New("trace"))) { return v8::FunctionTemplate::New(TraceExtension::Trace); } else if (name->Equals(String::New("js_trace"))) { return v8::FunctionTemplate::New(TraceExtension::JSTrace); } else if (name->Equals(String::New("js_entry_sp"))) { return v8::FunctionTemplate::New(TraceExtension::JSEntrySP); } else if (name->Equals(String::New("js_entry_sp_level2"))) { return v8::FunctionTemplate::New(TraceExtension::JSEntrySPLevel2); } else { CHECK(false); return v8::Handle<v8::FunctionTemplate>(); } } Address TraceExtension::GetFP(const v8::Arguments& args) { // Convert frame pointer from encoding as smis in the arguments to a pointer. CHECK_EQ(2, args.Length()); // Ignore second argument on 32-bit platform. #if defined(V8_HOST_ARCH_32_BIT) Address fp = *reinterpret_cast<Address*>(*args[0]); #elif defined(V8_HOST_ARCH_64_BIT) int64_t low_bits = *reinterpret_cast<uint64_t*>(*args[0]) >> 32; int64_t high_bits = *reinterpret_cast<uint64_t*>(*args[1]); Address fp = reinterpret_cast<Address>(high_bits | low_bits); #else #error Host architecture is neither 32-bit nor 64-bit. #endif printf("Trace: %p\n", fp); return fp; } v8::Handle<v8::Value> TraceExtension::Trace(const v8::Arguments& args) { DoTrace(GetFP(args)); return v8::Undefined(); } v8::Handle<v8::Value> TraceExtension::JSTrace(const v8::Arguments& args) { DoTraceHideCEntryFPAddress(GetFP(args)); return v8::Undefined(); } static Address GetJsEntrySp() { CHECK_NE(NULL, i::Isolate::Current()->thread_local_top()); return Isolate::js_entry_sp(i::Isolate::Current()->thread_local_top()); } v8::Handle<v8::Value> TraceExtension::JSEntrySP(const v8::Arguments& args) { CHECK_NE(0, GetJsEntrySp()); return v8::Undefined(); } v8::Handle<v8::Value> TraceExtension::JSEntrySPLevel2( const v8::Arguments& args) { v8::HandleScope scope; const Address js_entry_sp = GetJsEntrySp(); CHECK_NE(0, js_entry_sp); CompileRun("js_entry_sp();"); CHECK_EQ(js_entry_sp, GetJsEntrySp()); return v8::Undefined(); } static TraceExtension kTraceExtension; v8::DeclareExtension kTraceExtensionDeclaration(&kTraceExtension); static void InitializeVM() { if (env.IsEmpty()) { v8::HandleScope scope; const char* extensions[] = { "v8/trace" }; v8::ExtensionConfiguration config(1, extensions); env = v8::Context::New(&config); } v8::HandleScope scope; env->Enter(); } static bool IsAddressWithinFuncCode(JSFunction* function, Address addr) { i::Code* code = function->code(); return code->contains(addr); } static bool IsAddressWithinFuncCode(const char* func_name, Address addr) { v8::Local<v8::Value> func = env->Global()->Get(v8_str(func_name)); CHECK(func->IsFunction()); JSFunction* js_func = JSFunction::cast(*v8::Utils::OpenHandle(*func)); return IsAddressWithinFuncCode(js_func, addr); } // This C++ function is called as a constructor, to grab the frame pointer // from the calling function. When this function runs, the stack contains // a C_Entry frame and a Construct frame above the calling function's frame. static v8::Handle<Value> construct_call(const v8::Arguments& args) { i::StackFrameIterator frame_iterator; CHECK(frame_iterator.frame()->is_exit()); frame_iterator.Advance(); CHECK(frame_iterator.frame()->is_construct()); frame_iterator.Advance(); i::StackFrame* calling_frame = frame_iterator.frame(); CHECK(calling_frame->is_java_script()); #if defined(V8_HOST_ARCH_32_BIT) int32_t low_bits = reinterpret_cast<int32_t>(calling_frame->fp()); args.This()->Set(v8_str("low_bits"), v8_num(low_bits >> 1)); #elif defined(V8_HOST_ARCH_64_BIT) uint64_t fp = reinterpret_cast<uint64_t>(calling_frame->fp()); int32_t low_bits = static_cast<int32_t>(fp & 0xffffffff); int32_t high_bits = static_cast<int32_t>(fp >> 32); args.This()->Set(v8_str("low_bits"), v8_num(low_bits)); args.This()->Set(v8_str("high_bits"), v8_num(high_bits)); #else #error Host architecture is neither 32-bit nor 64-bit. #endif return args.This(); } // Use the API to create a JSFunction object that calls the above C++ function. void CreateFramePointerGrabberConstructor(const char* constructor_name) { Local<v8::FunctionTemplate> constructor_template = v8::FunctionTemplate::New(construct_call); constructor_template->SetClassName(v8_str("FPGrabber")); Local<Function> fun = constructor_template->GetFunction(); env->Global()->Set(v8_str(constructor_name), fun); } // Creates a global function named 'func_name' that calls the tracing // function 'trace_func_name' with an actual EBP register value, // encoded as one or two Smis. static void CreateTraceCallerFunction(const char* func_name, const char* trace_func_name) { i::EmbeddedVector<char, 256> trace_call_buf; i::OS::SNPrintF(trace_call_buf, "function %s() {" " fp = new FPGrabber();" " %s(fp.low_bits, fp.high_bits);" "}", func_name, trace_func_name); // Create the FPGrabber function, which grabs the caller's frame pointer // when called as a constructor. CreateFramePointerGrabberConstructor("FPGrabber"); // Compile the script. CompileRun(trace_call_buf.start()); } // This test verifies that stack tracing works when called during // execution of a native function called from JS code. In this case, // StackTracer uses Isolate::c_entry_fp as a starting point for stack // walking. TEST(CFromJSStackTrace) { // BUG(1303) Inlining of JSFuncDoTrace() in JSTrace below breaks this test. i::FLAG_use_inlining = false; TickSample sample; InitTraceEnv(&sample); InitializeVM(); v8::HandleScope scope; // Create global function JSFuncDoTrace which calls // extension function trace() with the current frame pointer value. CreateTraceCallerFunction("JSFuncDoTrace", "trace"); Local<Value> result = CompileRun( "function JSTrace() {" " JSFuncDoTrace();" "};\n" "JSTrace();\n" "true;"); CHECK(!result.IsEmpty()); // When stack tracer is invoked, the stack should look as follows: // script [JS] // JSTrace() [JS] // JSFuncDoTrace() [JS] [captures EBP value and encodes it as Smi] // trace(EBP) [native (extension)] // DoTrace(EBP) [native] // StackTracer::Trace CHECK(sample.has_external_callback); CHECK_EQ(FUNCTION_ADDR(TraceExtension::Trace), sample.external_callback); // Stack tracing will start from the first JS function, i.e. "JSFuncDoTrace" int base = 0; CHECK_GT(sample.frames_count, base + 1); CHECK(IsAddressWithinFuncCode("JSFuncDoTrace", sample.stack[base + 0])); CHECK(IsAddressWithinFuncCode("JSTrace", sample.stack[base + 1])); } // This test verifies that stack tracing works when called during // execution of JS code. However, as calling StackTracer requires // entering native code, we can only emulate pure JS by erasing // Isolate::c_entry_fp value. In this case, StackTracer uses passed frame // pointer value as a starting point for stack walking. TEST(PureJSStackTrace) { // This test does not pass with inlining enabled since inlined functions // don't appear in the stack trace. i::FLAG_use_inlining = false; TickSample sample; InitTraceEnv(&sample); InitializeVM(); v8::HandleScope scope; // Create global function JSFuncDoTrace which calls // extension function js_trace() with the current frame pointer value. CreateTraceCallerFunction("JSFuncDoTrace", "js_trace"); Local<Value> result = CompileRun( "function JSTrace() {" " JSFuncDoTrace();" "};\n" "function OuterJSTrace() {" " JSTrace();" "};\n" "OuterJSTrace();\n" "true;"); CHECK(!result.IsEmpty()); // When stack tracer is invoked, the stack should look as follows: // script [JS] // OuterJSTrace() [JS] // JSTrace() [JS] // JSFuncDoTrace() [JS] // js_trace(EBP) [native (extension)] // DoTraceHideCEntryFPAddress(EBP) [native] // StackTracer::Trace // CHECK(sample.has_external_callback); CHECK_EQ(FUNCTION_ADDR(TraceExtension::JSTrace), sample.external_callback); // Stack sampling will start from the caller of JSFuncDoTrace, i.e. "JSTrace" int base = 0; CHECK_GT(sample.frames_count, base + 1); CHECK(IsAddressWithinFuncCode("JSTrace", sample.stack[base + 0])); CHECK(IsAddressWithinFuncCode("OuterJSTrace", sample.stack[base + 1])); } static void CFuncDoTrace(byte dummy_parameter) { Address fp; #ifdef __GNUC__ fp = reinterpret_cast<Address>(__builtin_frame_address(0)); #elif defined _MSC_VER // Approximate a frame pointer address. We compile without base pointers, // so we can't trust ebp/rbp. fp = &dummy_parameter - 2 * sizeof(void*); // NOLINT #else #error Unexpected platform. #endif DoTrace(fp); } static int CFunc(int depth) { if (depth <= 0) { CFuncDoTrace(0); return 0; } else { return CFunc(depth - 1) + 1; } } // This test verifies that stack tracing doesn't crash when called on // pure native code. StackTracer only unrolls JS code, so we can't // get any meaningful info here. TEST(PureCStackTrace) { TickSample sample; InitTraceEnv(&sample); InitializeVM(); // Check that sampler doesn't crash CHECK_EQ(10, CFunc(10)); } TEST(JsEntrySp) { InitializeVM(); v8::HandleScope scope; CHECK_EQ(0, GetJsEntrySp()); CompileRun("a = 1; b = a + 1;"); CHECK_EQ(0, GetJsEntrySp()); CompileRun("js_entry_sp();"); CHECK_EQ(0, GetJsEntrySp()); CompileRun("js_entry_sp_level2();"); CHECK_EQ(0, GetJsEntrySp()); }