dart-lang/sdk
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity

[vm] Avoid going to runtime for String.split()

Browse Source 
This makes the small benchmark on the github issue more than 2.5x
faster.

Closes https://github.com/dart-lang/sdk/issues/46352

TEST=Existing test suite.

Change-Id: I82c53b3553e04f2afe23606b09b3199cb9b6a926
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/203502
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
This commit is contained in:
Martin Kustermann
2021-06-14 14:41:33 +00:00
committed by commit-bot@chromium.org
parent 159f487ea1
commit 65bca53b6e
4 changed files with 14 additions and 33 deletions
Download Patch File Download Diff File Expand all files Collapse all files
runtime/lib/string.cc
-29
View File
@@ -257,35 +257,6 @@ DEFINE_NATIVE_ENTRY(OneByteString_substringUnchecked, 0, 3) {
return OneByteString::New(receiver, start, end - start, Heap::kNew);
}
// This is high-performance code.
DEFINE_NATIVE_ENTRY(OneByteString_splitWithCharCode, 0, 2) {
const String& receiver =
String::CheckedHandle(zone, arguments->NativeArgAt(0));
ASSERT(receiver.IsOneByteString());
GET_NON_NULL_NATIVE_ARGUMENT(Smi, smi_split_code, arguments->NativeArgAt(1));
const intptr_t len = receiver.Length();
const intptr_t split_code = smi_split_code.Value();
const GrowableObjectArray& result = GrowableObjectArray::Handle(
zone, GrowableObjectArray::New(16, Heap::kNew));
String& str = String::Handle(zone);
intptr_t start = 0;
intptr_t i = 0;
for (; i < len; i++) {
if (split_code == OneByteString::CharAt(receiver, i)) {
str = OneByteString::SubStringUnchecked(receiver, start, (i - start),
Heap::kNew);
result.Add(str);
start = i + 1;
}
}
str = OneByteString::SubStringUnchecked(receiver, start, (i - start),
Heap::kNew);
result.Add(str);
result.SetTypeArguments(TypeArguments::Handle(
zone, isolate->group()->object_store()->type_argument_string()));
return result.ptr();
}
DEFINE_NATIVE_ENTRY(Internal_allocateOneByteString, 0, 1) {
GET_NON_NULL_NATIVE_ARGUMENT(Integer, length_obj, arguments->NativeArgAt(0));
const int64_t length = length_obj.AsInt64Value();
runtime/vm/bootstrap_natives.h
-1
View File
@@ -130,7 +130,6 @@ namespace dart {
V(StringBase_joinReplaceAllResult, 4) \
V(StringBuffer_createStringFromUint16Array, 3) \
V(OneByteString_substringUnchecked, 3) \
V(OneByteString_splitWithCharCode, 2) \
V(OneByteString_allocateFromOneByteList, 3) \
V(TwoByteString_allocateFromTwoByteList, 3) \
V(String_getHashCode, 1) \
runtime/vm/object_test.cc
+1 -1
View File
@@ -4511,7 +4511,7 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
"vmName\":\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{"
"\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
"patch\\/string_patch.dart\",\"_kind\":\"kernel\"},\"tokenPos\":32310,"
"\"endTokenPos\":44332},\"library\":{\"type\":\"@Library\",\"fixedId\":"
"\"endTokenPos\":44599},\"library\":{\"type\":\"@Library\",\"fixedId\":"
"true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
"\"identityHashCode\":0,\"kind\":\"String\",\"id\":\"\",\"length\":2,"
"\"valueAsString\":\"dw\"}",
sdk/lib/_internal/vm/lib/string_patch.dart
+13 -2
View File
@@ -985,8 +985,19 @@ class _OneByteString extends _StringBase {
String _substringUncheckedNative(int startIndex, int endIndex)
native "OneByteString_substringUnchecked";
List<String> _splitWithCharCode(int charCode)
native "OneByteString_splitWithCharCode";
List<String> _splitWithCharCode(int charCode) {
final parts = <String>[];
int i = 0;
int start = 0;
for (i = 0; i < this.length; ++i) {
if (this.codeUnitAt(i) == charCode) {
parts.add(this._substringUnchecked(start, i));
start = i + 1;
}
}
parts.add(this._substringUnchecked(start, i));
return parts;
}
List<String> split(Pattern pattern) {
// TODO(vegorov) investigate if this can be rewritten as `is _OneByteString`