buffer: rm createFromString and use fast Buffer.write

Author: ronag

benchmark/buffers/buffer-from.js

@@ -4,16 +4,16 @@ const common = require('../common.js');
 const assert = require('assert');
 const bench = common.createBenchmark(main, {
   source: [
-    'array',
-    'arraybuffer',
-    'arraybuffer-middle',
-    'buffer',
+    // 'array',
+    // 'arraybuffer',
+    // 'arraybuffer-middle',
+    // 'buffer',
     'string',
     'string-utf8',
     'string-base64',
-    'object',
-    'uint8array',
-    'uint16array',
+    // 'object',
+    // 'uint8array',
+    // 'uint16array',
   ],
   len: [100, 2048],
   n: [8e5],

lib/buffer.js

@@ -59,7 +59,6 @@ const {
   compare: _compare,
   compareOffset,
   copy: _copy,
-  createFromString,
   fill: bindingFill,
   isAscii: bindingIsAscii,
   isUtf8: bindingIsUtf8,
@@ -444,19 +443,12 @@ function allocate(size) {
 function fromStringFast(string, ops) {
   const length = ops.byteLength(string);
 
-  if (length >= (Buffer.poolSize >>> 1))
-    return createFromString(string, ops.encodingVal);
-
-  if (length > (poolSize - poolOffset))
-    createPool();
-  let b = new FastBuffer(allocPool, poolOffset, length);
+  let b = allocate(length);
   const actual = ops.write(b, string, 0, length);
   if (actual !== length) {
     // byteLength() may overestimate. That's a rare case, though.
     b = new FastBuffer(allocPool, poolOffset, actual);
   }
-  poolOffset += actual;
-  alignPool();
   return b;
 }
 

src/node_buffer.cc

@@ -530,17 +530,6 @@ MaybeLocal<Object> New(Environment* env,
 
 namespace {
 
-void CreateFromString(const FunctionCallbackInfo<Value>& args) {
-  CHECK(args[0]->IsString());
-  CHECK(args[1]->IsInt32());
-
-  enum encoding enc = static_cast<enum encoding>(args[1].As<Int32>()->Value());
-  Local<Object> buf;
-  if (New(args.GetIsolate(), args[0].As<String>(), enc).ToLocal(&buf))
-    args.GetReturnValue().Set(buf);
-}
-
-
 template <encoding encoding>
 void StringSlice(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
@@ -1436,7 +1425,6 @@ void Initialize(Local<Object> target,
   SetMethodNoSideEffect(context, target, "btoa", Btoa);
 
   SetMethod(context, target, "setBufferPrototype", SetBufferPrototype);
-  SetMethodNoSideEffect(context, target, "createFromString", CreateFromString);
 
   SetFastMethodNoSideEffect(context,
                             target,
@@ -1501,7 +1489,6 @@ void Initialize(Local<Object> target,
 
 void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
   registry->Register(SetBufferPrototype);
-  registry->Register(CreateFromString);
 
   registry->Register(SlowByteLengthUtf8);
   registry->Register(fast_byte_length_utf8.GetTypeInfo());