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Merged
graphite-app merged 1 commit into from
Apr 3, 2026
Merged

perf(napi/parser, linter/plugins): speed up decoding strings in raw transfer #21021

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88 changes: 43 additions & 45 deletions apps/oxlint/src-js/generated/deserialize.js
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Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,7 @@ let uint8,
uint32,
float64,
sourceText,
sourceTextLatin,
sourceStartPos = 0,
firstNonAsciiPos = 0,
parent = null,
Expand All @@ -16,14 +17,18 @@ let uint8,
const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String,
NodeProto = Object.create(Object.prototype, {
loc: {
get() {
return getLoc(this);
},
enumerable: true,
{ latin1Slice } = Buffer.prototype,
stringDecodeArrays = Array(65).fill(null);
for (let i = 0; i <= 64; i++) stringDecodeArrays[i] = Array(i).fill(0);

const NodeProto = Object.create(Object.prototype, {
loc: {
get() {
return getLoc(this);
},
});
enumerable: true,
},
});

export function deserializeProgramOnly(
buffer,
Expand All @@ -41,20 +46,23 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceStartPos + sourceByteLen;
else {
if (sourceText.length === sourceByteLen) {
firstNonAsciiPos = sourceStartPos + sourceByteLen;
sourceTextLatin = sourceText;
} else {
let i = sourceStartPos,
sourceEndPos = sourceStartPos + sourceByteLen;
for (; i < sourceEndPos && uint8[i] < 128; i++);
firstNonAsciiPos = i;
sourceTextLatin = latin1Slice.call(uint8, sourceStartPos, sourceEndPos);
}
getLoc = getLocInput;
return deserialize(uint32[536870900]);
}

export function resetBuffer() {
// Clear buffer and source text string to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = void 0;
// Clear buffer and source text strings to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = sourceTextLatin = void 0;
}

function deserializeProgram(pos) {
Expand Down Expand Up @@ -5880,40 +5888,30 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
let end = pos + len;
// Note: Tried reducing this check to a single branch by making the comparison the equivalent of this Rust:
// `end.wrapping_sub(sourceStartPos) <= firstNonAsciiOffset`.
//
// The JS versions tried were:
// - `((end - sourceStartPos) >>> 0) <= firstNonAsciiOffset`
// - `((end - sourceStartPos) & 0x7FFF_FFFF) <= firstNonAsciiOffset`
// But it turned out that these are both slower by 5-10% on files which are all ASCII.
//
// `>>>` is slower as V8 can't assume result fits in an SMI (which is a 32-bit *signed* integer),
// as result could be greater or equal to `2 ** 31`. So it converts both the comparison's operands to `float64`s
// and does float compare (which is slower than integer compare).
//
// `& 0x7FFF_FFFF` is slower as it has a longer chain of data dependencies than the 2 independent
// branch comparisons.
//
// Both branches are very predictable, so 2 branches wins.
if (pos >= sourceStartPos && end <= firstNonAsciiPos)
return sourceText.substr(pos - sourceStartPos, len);
// Use `TextDecoder` for strings longer than 9 bytes.
// For shorter strings, the byte-by-byte loop below avoids native call overhead.
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
c;
do {
c = uint8[pos++];
if (c < 128) out += fromCharCode(c);
else {
out += decodeStr(uint8.subarray(pos - 1, end));
break;
}
} while (pos < end);
return out;
let end = pos + len,
isInSourceRegion = pos >= sourceStartPos;
if (isInSourceRegion && end <= firstNonAsciiPos)
return sourceTextLatin.substr(pos - sourceStartPos, len);
// Use `TextDecoder` for strings longer than 64 bytes
if (len > 64) return decodeStr(uint8.subarray(pos, end));
// If string is in source region, use slice of `sourceTextLatin` if all ASCII
if (isInSourceRegion) {
// Check if all bytes are ASCII, use `TextDecoder` if not
for (let i = pos; i < end; i++) if (uint8[i] >= 128) return decodeStr(uint8.subarray(pos, end));
// String is all ASCII, so slice from `sourceTextLatin`
return sourceTextLatin.substr(pos - sourceStartPos, len);
}
// String is not in source region - use `fromCharCode.apply` with a temp array of correct length.
// Copy bytes into temp array.
// If any byte is non-ASCII, use `TextDecoder`.
let arr = stringDecodeArrays[len];
for (let i = 0; i < len; i++) {
let b = uint8[pos + i];
if (b >= 128) return decodeStr(uint8.subarray(pos, end));
arr[i] = b;
}
// Call `fromCharCode` with temp array
return fromCharCode.apply(null, arr);
}

function deserializeVecDirective(pos) {
Expand Down
55 changes: 34 additions & 21 deletions napi/parser/src-js/generated/deserialize/js.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,13 +5,19 @@ let uint8,
uint32,
float64,
sourceText,
sourceTextLatin,
sourceEndPos = 0,
firstNonAsciiPos = 0;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;
{ fromCharCode } = String,
{ latin1Slice } = Buffer.prototype,
stringDecodeArrays = Array(65).fill(null);
for (let i = 0; i <= 64; i++) stringDecodeArrays[i] = Array(i).fill(0);

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -22,18 +28,21 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
if (sourceText.length === sourceByteLen) {
firstNonAsciiPos = sourceByteLen;
sourceTextLatin = sourceText;
} else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
sourceTextLatin = latin1Slice.call(uint8, 0, sourceByteLen);
}
return deserialize(uint32[536870900]);
}

export function resetBuffer() {
// Clear buffer and source text string to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = void 0;
// Clear buffer and source text strings to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = sourceTextLatin = void 0;
}

function deserializeProgram(pos) {
Expand Down Expand Up @@ -4547,22 +4556,26 @@ function deserializeStr(pos) {
if (len === 0) return "";
pos = uint32[pos32];
let end = pos + len;
if (end <= firstNonAsciiPos) return sourceText.substr(pos, len);
// Use `TextDecoder` for strings longer than 9 bytes.
// For shorter strings, the byte-by-byte loop below avoids native call overhead.
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
c;
do {
c = uint8[pos++];
if (c < 128) out += fromCharCode(c);
else {
out += decodeStr(uint8.subarray(pos - 1, end));
break;
}
} while (pos < end);
return out;
if (end <= firstNonAsciiPos) return sourceTextLatin.substr(pos, len);
// Use `TextDecoder` for strings longer than 64 bytes
if (len > 64) return decodeStr(uint8.subarray(pos, end));
if (pos < sourceEndPos) {
// Check if all bytes are ASCII, use `TextDecoder` if not
for (let i = pos; i < end; i++) if (uint8[i] >= 128) return decodeStr(uint8.subarray(pos, end));
// String is all ASCII, so slice from `sourceTextLatin`
return sourceTextLatin.substr(pos, len);
}
// String is not in source region - use `fromCharCode.apply` with a temp array of correct length.
// Copy bytes into temp array.
// If any byte is non-ASCII, use `TextDecoder`.
let arr = stringDecodeArrays[len];
for (let i = 0; i < len; i++) {
let b = uint8[pos + i];
if (b >= 128) return decodeStr(uint8.subarray(pos, end));
arr[i] = b;
}
// Call `fromCharCode` with temp array
return fromCharCode.apply(null, arr);
}

function deserializeVecComment(pos) {
Expand Down
55 changes: 34 additions & 21 deletions napi/parser/src-js/generated/deserialize/js_parent.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,14 +5,20 @@ let uint8,
uint32,
float64,
sourceText,
sourceTextLatin,
sourceEndPos = 0,
firstNonAsciiPos = 0,
parent = null;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;
{ fromCharCode } = String,
{ latin1Slice } = Buffer.prototype,
stringDecodeArrays = Array(65).fill(null);
for (let i = 0; i <= 64; i++) stringDecodeArrays[i] = Array(i).fill(0);

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -23,18 +29,21 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
if (sourceText.length === sourceByteLen) {
firstNonAsciiPos = sourceByteLen;
sourceTextLatin = sourceText;
} else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
sourceTextLatin = latin1Slice.call(uint8, 0, sourceByteLen);
}
return deserialize(uint32[536870900]);
}

export function resetBuffer() {
// Clear buffer and source text string to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = void 0;
// Clear buffer and source text strings to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = sourceTextLatin = void 0;
}

function deserializeProgram(pos) {
Expand Down Expand Up @@ -5078,22 +5087,26 @@ function deserializeStr(pos) {
if (len === 0) return "";
pos = uint32[pos32];
let end = pos + len;
if (end <= firstNonAsciiPos) return sourceText.substr(pos, len);
// Use `TextDecoder` for strings longer than 9 bytes.
// For shorter strings, the byte-by-byte loop below avoids native call overhead.
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
c;
do {
c = uint8[pos++];
if (c < 128) out += fromCharCode(c);
else {
out += decodeStr(uint8.subarray(pos - 1, end));
break;
}
} while (pos < end);
return out;
if (end <= firstNonAsciiPos) return sourceTextLatin.substr(pos, len);
// Use `TextDecoder` for strings longer than 64 bytes
if (len > 64) return decodeStr(uint8.subarray(pos, end));
if (pos < sourceEndPos) {
// Check if all bytes are ASCII, use `TextDecoder` if not
for (let i = pos; i < end; i++) if (uint8[i] >= 128) return decodeStr(uint8.subarray(pos, end));
// String is all ASCII, so slice from `sourceTextLatin`
return sourceTextLatin.substr(pos, len);
}
// String is not in source region - use `fromCharCode.apply` with a temp array of correct length.
// Copy bytes into temp array.
// If any byte is non-ASCII, use `TextDecoder`.
let arr = stringDecodeArrays[len];
for (let i = 0; i < len; i++) {
let b = uint8[pos + i];
if (b >= 128) return decodeStr(uint8.subarray(pos, end));
arr[i] = b;
}
// Call `fromCharCode` with temp array
return fromCharCode.apply(null, arr);
}

function deserializeVecComment(pos) {
Expand Down
55 changes: 34 additions & 21 deletions napi/parser/src-js/generated/deserialize/js_range.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,13 +5,19 @@ let uint8,
uint32,
float64,
sourceText,
sourceTextLatin,
sourceEndPos = 0,
firstNonAsciiPos = 0;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;
{ fromCharCode } = String,
{ latin1Slice } = Buffer.prototype,
stringDecodeArrays = Array(65).fill(null);
for (let i = 0; i <= 64; i++) stringDecodeArrays[i] = Array(i).fill(0);

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -22,18 +28,21 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
if (sourceText.length === sourceByteLen) {
firstNonAsciiPos = sourceByteLen;
sourceTextLatin = sourceText;
} else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
sourceTextLatin = latin1Slice.call(uint8, 0, sourceByteLen);
}
return deserialize(uint32[536870900]);
}

export function resetBuffer() {
// Clear buffer and source text string to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = void 0;
// Clear buffer and source text strings to allow them to be garbage collected
uint8 = uint32 = float64 = sourceText = sourceTextLatin = void 0;
}

function deserializeProgram(pos) {
Expand Down Expand Up @@ -5089,22 +5098,26 @@ function deserializeStr(pos) {
if (len === 0) return "";
pos = uint32[pos32];
let end = pos + len;
if (end <= firstNonAsciiPos) return sourceText.substr(pos, len);
// Use `TextDecoder` for strings longer than 9 bytes.
// For shorter strings, the byte-by-byte loop below avoids native call overhead.
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
c;
do {
c = uint8[pos++];
if (c < 128) out += fromCharCode(c);
else {
out += decodeStr(uint8.subarray(pos - 1, end));
break;
}
} while (pos < end);
return out;
if (end <= firstNonAsciiPos) return sourceTextLatin.substr(pos, len);
// Use `TextDecoder` for strings longer than 64 bytes
if (len > 64) return decodeStr(uint8.subarray(pos, end));
if (pos < sourceEndPos) {
// Check if all bytes are ASCII, use `TextDecoder` if not
for (let i = pos; i < end; i++) if (uint8[i] >= 128) return decodeStr(uint8.subarray(pos, end));
// String is all ASCII, so slice from `sourceTextLatin`
return sourceTextLatin.substr(pos, len);
}
// String is not in source region - use `fromCharCode.apply` with a temp array of correct length.
// Copy bytes into temp array.
// If any byte is non-ASCII, use `TextDecoder`.
let arr = stringDecodeArrays[len];
for (let i = 0; i < len; i++) {
let b = uint8[pos + i];
if (b >= 128) return decodeStr(uint8.subarray(pos, end));
arr[i] = b;
}
// Call `fromCharCode` with temp array
return fromCharCode.apply(null, arr);
}

function deserializeVecComment(pos) {
Expand Down
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