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

perf(napi/parser, linter/plugins): simplify branch condition in deserializeStr #21019

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35 changes: 24 additions & 11 deletions apps/oxlint/src-js/generated/deserialize.js
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Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,6 @@ let uint8,
uint32,
float64,
sourceText,
sourceIsAscii,
sourceStartPos,
firstNonAsciiPos,
parent = null,
Expand Down Expand Up @@ -42,14 +41,12 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = sourceStartPos, e = sourceStartPos + sourceByteLen; i < e; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i - sourceStartPos;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceStartPos + sourceByteLen;
else {
let i = sourceStartPos,
sourceEndPos = sourceStartPos + sourceByteLen;
for (; i < sourceEndPos && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
getLoc = getLocInput;
return deserialize(uint32[536870900]);
Expand Down Expand Up @@ -5883,11 +5880,27 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos >= sourceStartPos && (sourceIsAscii || pos - sourceStartPos + len <= firstNonAsciiPos))
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 8 additions & 13 deletions napi/parser/src-js/generated/deserialize/js.js
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Original file line number Diff line number Diff line change
@@ -1,14 +1,13 @@
// Auto-generated code, DO NOT EDIT DIRECTLY!
// To edit this generated file you have to edit `tasks/ast_tools/src/generators/raw_transfer.rs`.

let uint8, uint32, float64, sourceText, sourceIsAscii, sourceEndPos, firstNonAsciiPos;
let uint8, uint32, float64, sourceText, firstNonAsciiPos;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -19,14 +18,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -4546,11 +4542,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 7 additions & 14 deletions napi/parser/src-js/generated/deserialize/js_parent.js
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Original file line number Diff line number Diff line change
Expand Up @@ -5,8 +5,6 @@ let uint8,
uint32,
float64,
sourceText,
sourceIsAscii,
sourceEndPos,
firstNonAsciiPos,
parent = null;

Expand All @@ -15,7 +13,6 @@ const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -26,14 +23,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -5083,11 +5077,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 8 additions & 13 deletions napi/parser/src-js/generated/deserialize/js_range.js
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Original file line number Diff line number Diff line change
@@ -1,14 +1,13 @@
// Auto-generated code, DO NOT EDIT DIRECTLY!
// To edit this generated file you have to edit `tasks/ast_tools/src/generators/raw_transfer.rs`.

let uint8, uint32, float64, sourceText, sourceIsAscii, sourceEndPos, firstNonAsciiPos;
let uint8, uint32, float64, sourceText, firstNonAsciiPos;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -19,14 +18,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -5088,11 +5084,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 7 additions & 14 deletions napi/parser/src-js/generated/deserialize/js_range_parent.js
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Original file line number Diff line number Diff line change
Expand Up @@ -5,8 +5,6 @@ let uint8,
uint32,
float64,
sourceText,
sourceIsAscii,
sourceEndPos,
firstNonAsciiPos,
parent = null;

Expand All @@ -15,7 +13,6 @@ const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -26,14 +23,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -5628,11 +5622,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 8 additions & 13 deletions napi/parser/src-js/generated/deserialize/ts.js
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Open in desktop
Original file line number Diff line number Diff line change
@@ -1,14 +1,13 @@
// Auto-generated code, DO NOT EDIT DIRECTLY!
// To edit this generated file you have to edit `tasks/ast_tools/src/generators/raw_transfer.rs`.

let uint8, uint32, float64, sourceText, sourceIsAscii, sourceEndPos, firstNonAsciiPos;
let uint8, uint32, float64, sourceText, firstNonAsciiPos;

const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
decodeStr = textDecoder.decode.bind(textDecoder),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -19,14 +18,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -4855,11 +4851,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
21 changes: 7 additions & 14 deletions napi/parser/src-js/generated/deserialize/ts_parent.js
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Original file line number Diff line number Diff line change
Expand Up @@ -5,8 +5,6 @@ let uint8,
uint32,
float64,
sourceText,
sourceIsAscii,
sourceEndPos,
firstNonAsciiPos,
parent = null;

Expand All @@ -15,7 +13,6 @@ const textDecoder = new TextDecoder("utf-8", { ignoreBOM: true }),
{ fromCharCode } = String;

export function deserialize(buffer, sourceText, sourceByteLen) {
sourceEndPos = sourceByteLen;
let data = deserializeWith(buffer, sourceText, sourceByteLen, null, deserializeRawTransferData);
resetBuffer();
return data;
Expand All @@ -26,14 +23,11 @@ function deserializeWith(buffer, sourceTextInput, sourceByteLen, getLocInput, de
uint32 = buffer.uint32;
float64 = buffer.float64;
sourceText = sourceTextInput;
sourceIsAscii = sourceText.length === sourceByteLen;
if (!sourceIsAscii) {
firstNonAsciiPos = sourceByteLen;
for (let i = 0; i < sourceByteLen; i++)
if (uint8[i] >= 128) {
firstNonAsciiPos = i;
break;
}
if (sourceText.length === sourceByteLen) firstNonAsciiPos = sourceByteLen;
else {
let i = 0;
for (; i < sourceByteLen && uint8[i] < 128; i++);
firstNonAsciiPos = i;
}
return deserialize(uint32[536870900]);
}
Expand Down Expand Up @@ -5419,11 +5413,10 @@ function deserializeStr(pos) {
len = uint32[pos32 + 2];
if (len === 0) return "";
pos = uint32[pos32];
if (pos < sourceEndPos && (sourceIsAscii || pos + len <= firstNonAsciiPos))
return sourceText.substr(pos, len);
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.
let end = pos + len;
if (len > 9) return decodeStr(uint8.subarray(pos, end));
// Shorter strings decode by hand to avoid native call
let out = "",
Expand Down
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