bootstrap: build fast APIs in pre-execution

Fast APIs need to work with ArrayBuffers which we need
to rebuild connections to after deserializing them
from the snapshot. For now, postpone their creation
until pre-execution to simplify the process.

PR-URL: #32984
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>

lib/internal/bootstrap/node.js

@@ -80,8 +80,6 @@ const rawMethods = internalBinding('process_methods');
 
   const wrapped = perThreadSetup.wrapProcessMethods(rawMethods);
   process._rawDebug = wrapped._rawDebug;
-  process.hrtime = wrapped.hrtime;
-  process.hrtime.bigint = wrapped.hrtimeBigInt;
   process.cpuUsage = wrapped.cpuUsage;
   process.resourceUsage = wrapped.resourceUsage;
   process.memoryUsage = wrapped.memoryUsage;

lib/internal/bootstrap/pre_execution.js

@@ -74,11 +74,19 @@ function prepareMainThreadExecution(expandArgv1 = false) {
 }
 
 function patchProcessObject(expandArgv1) {
+  const binding = internalBinding('process_methods');
+  binding.patchProcessObject(process);
+
+  // TODO(joyeecheung): snapshot fast APIs (which need to work with
+  // array buffers, whose connection with C++ needs to be rebuilt after
+  // deserialization).
   const {
-    patchProcessObject: patchProcessObjectNative
-  } = internalBinding('process_methods');
+    hrtime,
+    hrtimeBigInt
+  } = require('internal/process/per_thread').getFastAPIs(binding);
 
-  patchProcessObjectNative(process);
+  process.hrtime = hrtime;
+  process.hrtime.bigint = hrtimeBigInt;
 
   ObjectDefineProperty(process, 'argv0', {
     enumerable: true,

lib/internal/process/per_thread.js

@@ -37,10 +37,56 @@ function assert(x, msg) {
   if (!x) throw new ERR_ASSERTION(msg || 'assertion error');
 }
 
+function getFastAPIs(binding) {
+  const {
+    hrtime: _hrtime
+  } = binding.getFastAPIs();
+
+  // The 3 entries filled in by the original process.hrtime contains
+  // the upper/lower 32 bits of the second part of the value,
+  // and the remaining nanoseconds of the value.
+  const hrValues = new Uint32Array(_hrtime.buffer);
+
+  function hrtime(time) {
+    _hrtime.hrtime();
+
+    if (time !== undefined) {
+      if (!ArrayIsArray(time)) {
+        throw new ERR_INVALID_ARG_TYPE('time', 'Array', time);
+      }
+      if (time.length !== 2) {
+        throw new ERR_OUT_OF_RANGE('time', 2, time.length);
+      }
+
+      const sec = (hrValues[0] * 0x100000000 + hrValues[1]) - time[0];
+      const nsec = hrValues[2] - time[1];
+      const needsBorrow = nsec < 0;
+      return [needsBorrow ? sec - 1 : sec, needsBorrow ? nsec + 1e9 : nsec];
+    }
+
+    return [
+      hrValues[0] * 0x100000000 + hrValues[1],
+      hrValues[2]
+    ];
+  }
+
+  // Use a BigUint64Array in the closure because this is actually a bit
+  // faster than simply returning a BigInt from C++ in V8 7.1.
+  const hrBigintValues = new BigUint64Array(_hrtime.buffer, 0, 1);
+  function hrtimeBigInt() {
+    _hrtime.hrtimeBigInt();
+    return hrBigintValues[0];
+  }
+
+  return {
+    hrtime,
+    hrtimeBigInt,
+  };
+}
+
 // The execution of this function itself should not cause any side effects.
 function wrapProcessMethods(binding) {
   const {
-    hrtime: _hrtime,
     cpuUsage: _cpuUsage,
     memoryUsage: _memoryUsage,
     resourceUsage: _resourceUsage
@@ -109,42 +155,6 @@ function wrapProcessMethods(binding) {
         num >= 0;
   }
 
-  // The 3 entries filled in by the original process.hrtime contains
-  // the upper/lower 32 bits of the second part of the value,
-  // and the remaining nanoseconds of the value.
-  const hrValues = new Uint32Array(_hrtime.buffer);
-
-  function hrtime(time) {
-    _hrtime.hrtime();
-
-    if (time !== undefined) {
-      if (!ArrayIsArray(time)) {
-        throw new ERR_INVALID_ARG_TYPE('time', 'Array', time);
-      }
-      if (time.length !== 2) {
-        throw new ERR_OUT_OF_RANGE('time', 2, time.length);
-      }
-
-      const sec = (hrValues[0] * 0x100000000 + hrValues[1]) - time[0];
-      const nsec = hrValues[2] - time[1];
-      const needsBorrow = nsec < 0;
-      return [needsBorrow ? sec - 1 : sec, needsBorrow ? nsec + 1e9 : nsec];
-    }
-
-    return [
-      hrValues[0] * 0x100000000 + hrValues[1],
-      hrValues[2]
-    ];
-  }
-
-  // Use a BigUint64Array in the closure because this is actually a bit
-  // faster than simply returning a BigInt from C++ in V8 7.1.
-  const hrBigintValues = new BigUint64Array(_hrtime.buffer, 0, 1);
-  function hrtimeBigInt() {
-    _hrtime.hrtimeBigInt();
-    return hrBigintValues[0];
-  }
-
   const memValues = new Float64Array(5);
   function memoryUsage() {
     _memoryUsage(memValues);
@@ -225,8 +235,6 @@ function wrapProcessMethods(binding) {
 
   return {
     _rawDebug,
-    hrtime,
-    hrtimeBigInt,
     cpuUsage,
     resourceUsage,
     memoryUsage,
@@ -356,6 +364,7 @@ function toggleTraceCategoryState(asyncHooksEnabled) {
 
 module.exports = {
   toggleTraceCategoryState,
+  getFastAPIs,
   assert,
   buildAllowedFlags,
   wrapProcessMethods

src/node_process_methods.cc

@@ -504,6 +504,16 @@ class FastHrtime : public BaseObject {
   std::shared_ptr<BackingStore> backing_store_;
 };
 
+static void GetFastAPIs(const FunctionCallbackInfo<Value>& args) {
+  Environment* env = Environment::GetCurrent(args);
+  Local<Object> ret = Object::New(env->isolate());
+  ret->Set(env->context(),
+           FIXED_ONE_BYTE_STRING(env->isolate(), "hrtime"),
+           FastHrtime::New(env))
+      .ToChecked();
+  args.GetReturnValue().Set(ret);
+}
+
 static void InitializeProcessMethods(Local<Object> target,
                                      Local<Value> unused,
                                      Local<Context> context,
@@ -534,12 +544,7 @@ static void InitializeProcessMethods(Local<Object> target,
   env->SetMethod(target, "reallyExit", ReallyExit);
   env->SetMethodNoSideEffect(target, "uptime", Uptime);
   env->SetMethod(target, "patchProcessObject", PatchProcessObject);
-
-  target
-      ->Set(env->context(),
-            FIXED_ONE_BYTE_STRING(env->isolate(), "hrtime"),
-            FastHrtime::New(env))
-      .ToChecked();
+  env->SetMethod(target, "getFastAPIs", GetFastAPIs);
 }
 
 }  // namespace node

test/cctest/test_base_object_ptr.cc

@@ -16,7 +16,7 @@ using v8::Object;
 
 // Environments may come with existing BaseObject instances.
 // This variable offsets the expected BaseObject counts.
-static const int BASE_OBJECT_COUNT = 1;
+static const int BASE_OBJECT_COUNT = 0;
 
 class BaseObjectPtrTest : public EnvironmentTestFixture {};