47 lines
1.5 KiB
JavaScript
47 lines
1.5 KiB
JavaScript
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import { traverse, shiftSection } from "@webassemblyjs/ast";
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import { encodeU32 } from "@webassemblyjs/wasm-gen/lib/encoder";
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import { overrideBytesInBuffer } from "@webassemblyjs/helper-buffer";
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function shiftFollowingSections(ast, _ref, deltaInSizeEncoding) {
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var section = _ref.section;
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// Once we hit our section every that is after needs to be shifted by the delta
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var encounteredSection = false;
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traverse(ast, {
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SectionMetadata: function SectionMetadata(path) {
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if (path.node.section === section) {
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encounteredSection = true;
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return;
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}
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if (encounteredSection === true) {
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shiftSection(ast, path.node, deltaInSizeEncoding);
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}
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}
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});
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}
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export function shrinkPaddedLEB128(ast, uint8Buffer) {
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traverse(ast, {
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SectionMetadata: function SectionMetadata(_ref2) {
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var node = _ref2.node;
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/**
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* Section size
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*/
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{
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var newu32Encoded = encodeU32(node.size.value);
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var newu32EncodedLen = newu32Encoded.length;
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var start = node.size.loc.start.column;
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var end = node.size.loc.end.column;
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var oldu32EncodedLen = end - start;
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if (newu32EncodedLen !== oldu32EncodedLen) {
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var deltaInSizeEncoding = oldu32EncodedLen - newu32EncodedLen;
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uint8Buffer = overrideBytesInBuffer(uint8Buffer, start, end, newu32Encoded);
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shiftFollowingSections(ast, node, -deltaInSizeEncoding);
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}
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}
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}
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});
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return uint8Buffer;
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}
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