Various extension-related cleanup and simplifications.

test/cctest/trace-extension.cc

Index: test/cctest/trace-extension.cc
diff --git a/test/cctest/trace-extension.cc b/test/cctest/trace-extension.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2da681316630dc8c28eb5eedf94436dceabc8ef4
--- /dev/null
+++ b/test/cctest/trace-extension.cc
@@ -0,0 +1,142 @@
+// Copyright 2014 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.
+
+#include "trace-extension.h"
+
+#include "cctest.h"
+#include "sampler.h"
+
+namespace v8 {
+namespace internal {
+
+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::GetNativeFunctionTemplate(
+    v8::Isolate* isolate, v8::Handle<v8::String> name) {
+  if (name->Equals(v8::String::NewFromUtf8(isolate, "trace"))) {
+    return v8::FunctionTemplate::New(isolate, TraceExtension::Trace);
+  } else if (name->Equals(v8::String::NewFromUtf8(isolate, "js_trace"))) {
+    return v8::FunctionTemplate::New(isolate, TraceExtension::JSTrace);
+  } else if (name->Equals(v8::String::NewFromUtf8(isolate, "js_entry_sp"))) {
+    return v8::FunctionTemplate::New(isolate, TraceExtension::JSEntrySP);
+  } else if (name->Equals(v8::String::NewFromUtf8(isolate,
+                                                  "js_entry_sp_level2"))) {
+    return v8::FunctionTemplate::New(isolate, TraceExtension::JSEntrySPLevel2);
+  } else {
+    CHECK(false);
+    return v8::Handle<v8::FunctionTemplate>();
+  }
+}
+
+
+Address TraceExtension::GetFP(const v8::FunctionCallbackInfo<v8::Value>& 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;
+}
+
+
+static struct {
+  TickSample* sample;
+} trace_env = { NULL };
+
+
+void TraceExtension::InitTraceEnv(TickSample* sample) {
+  trace_env.sample = sample;
+}
+
+
+void TraceExtension::DoTrace(Address fp) {
+  RegisterState regs;
+  regs.fp = fp;
+  // sp is only used to define stack high bound
+  regs.sp =
+      reinterpret_cast<Address>(trace_env.sample) - 10240;
+  trace_env.sample->Init(CcTest::i_isolate(), regs);
+}
+
+
+void TraceExtension::Trace(const v8::FunctionCallbackInfo<v8::Value>& args) {
+  DoTrace(GetFP(args));
+}
+
+
+// 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 =
+      *(CcTest::i_isolate()->c_entry_fp_address());
+  CHECK(saved_c_frame_fp);
+  *(CcTest::i_isolate()->c_entry_fp_address()) = 0;
+  i::TraceExtension::DoTrace(fp);
+  *(CcTest::i_isolate()->c_entry_fp_address()) = saved_c_frame_fp;
+}
+
+
+void TraceExtension::JSTrace(const v8::FunctionCallbackInfo<v8::Value>& args) {
+  DoTraceHideCEntryFPAddress(GetFP(args));
+}
+
+
+Address TraceExtension::GetJsEntrySp() {
+  CHECK_NE(NULL, CcTest::i_isolate()->thread_local_top());
+  return CcTest::i_isolate()->js_entry_sp();
+}
+
+
+void TraceExtension::JSEntrySP(
+    const v8::FunctionCallbackInfo<v8::Value>& args) {
+  CHECK_NE(0, GetJsEntrySp());
+}
+
+
+void TraceExtension::JSEntrySPLevel2(
+    const v8::FunctionCallbackInfo<v8::Value>& args) {
+  v8::HandleScope scope(args.GetIsolate());
+  const Address js_entry_sp = GetJsEntrySp();
+  CHECK_NE(0, js_entry_sp);
+  CompileRun("js_entry_sp();");
+  CHECK_EQ(js_entry_sp, GetJsEntrySp());
+}
+
+
+} }  // namespace v8::internal