Avoid deopt from differing map types

jridgewell · Jun 28, 2024 · 154656b · 154656b
1 parent 9d343e4
commit 154656b
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Showing 2 changed files with 18 additions and 29 deletions.
diff --git a/src/scopes.ts b/src/scopes.ts
@@ -108,7 +108,14 @@ function _encodeOriginalScopes(
     encodeInteger(writer, v, 0);
   }
 
-  index = encodeTree(scopes, index, writer, state, endLine, endColumn, _encodeOriginalScopes);
+  for (index++; index < scopes.length; ) {
+    const next = scopes[index];
+    const { 0: l, 1: c } = next;
+    if (l > endLine || (l === endLine && c >= endColumn)) {
+      break;
+    }
+    index = _encodeOriginalScopes(scopes, index, writer, state);
+  }
 
   writer.write(comma);
   state[0] = encodeInteger(writer, endLine, state[0]);
@@ -124,7 +131,6 @@ export function decodeGeneratedRanges(input: string): GeneratedRange[] {
   const stack: GeneratedRange[] = [];
 
   let genLine = 0;
-  let genColumn = 0;
   let definitionSourcesIndex = 0;
   let definitionScopeIndex = 0;
   let callsiteSourcesIndex = 0;
@@ -135,7 +141,7 @@ export function decodeGeneratedRanges(input: string): GeneratedRange[] {
 
   do {
     const semi = reader.indexOf(';');
-    genColumn = 0;
+    let genColumn = 0;
 
     for (; reader.pos < semi; reader.pos++) {
       genColumn = decodeInteger(reader, genColumn);
@@ -309,7 +315,14 @@ function _encodeGeneratedRanges(
     }
   }
 
-  index = encodeTree(ranges, index, writer, state, endLine, endColumn, _encodeGeneratedRanges);
+  for (index++; index < ranges.length; ) {
+    const next = ranges[index];
+    const { 0: l, 1: c } = next;
+    if (l > endLine || (l === endLine && c >= endColumn)) {
+      break;
+    }
+    index = _encodeGeneratedRanges(ranges, index, writer, state);
+  }
 
   if (state[0] < endLine) {
     catchupLine(writer, state[0], endLine);
@@ -323,26 +336,6 @@ function _encodeGeneratedRanges(
   return index;
 }
 
-function encodeTree<T extends [number, number, ...number[]], S>(
-  arr: T[],
-  index: number,
-  writer: StringWriter,
-  state: S,
-  endLine: number,
-  endColumn: number,
-  fn: (arr: T[], index: number, writer: StringWriter, state: S) => number,
-): number {
-  for (index++; index < arr.length; ) {
-    const next = arr[index];
-    const { 0: l, 1: c } = next;
-    if (l > endLine || (l === endLine && c >= endColumn)) {
-      break;
-    }
-    index = fn(arr, index, writer, state);
-  }
-  return index;
-}
-
 function catchupLine(writer: StringWriter, lastLine: number, line: number) {
   do {
     writer.write(semicolon);

diff --git a/src/sourcemap-codec.ts b/src/sourcemap-codec.ts
@@ -78,10 +78,7 @@ function sortComparator(a: SourceMapSegment, b: SourceMapSegment): number {
 export function encode(decoded: SourceMapMappings): string;
 export function encode(decoded: Readonly<SourceMapMappings>): string;
 export function encode(decoded: Readonly<SourceMapMappings>): string {
-  // We can push up to 5 ints, each int can take at most 7 chars, and we
-  // may push a comma.
   const writer = new StringWriter();
-  let genColumn = 0;
   let sourcesIndex = 0;
   let sourceLine = 0;
   let sourceColumn = 0;
@@ -90,10 +87,9 @@ export function encode(decoded: Readonly<SourceMapMappings>): string {
   for (let i = 0; i < decoded.length; i++) {
     const line = decoded[i];
     if (i > 0) writer.write(semicolon);
-
     if (line.length === 0) continue;
 
-    genColumn = 0;
+    let genColumn = 0;
 
     for (let j = 0; j < line.length; j++) {
       const segment = line[j];