You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
78 lines
2.8 KiB
78 lines
2.8 KiB
4 years ago
|
import { encodeU32 } from "@webassemblyjs/wasm-gen";
|
||
|
|
import { getSectionMetadata, traverse, shiftSection } from "@webassemblyjs/ast";
|
||
|
|
import { overrideBytesInBuffer } from "@webassemblyjs/helper-buffer";
|
||
|
|
export function resizeSectionByteSize(ast, uint8Buffer, section, deltaBytes) {
|
||
|
|
var sectionMetadata = getSectionMetadata(ast, section);
|
||
|
|
|
||
|
|
if (typeof sectionMetadata === "undefined") {
|
||
|
|
throw new Error("Section metadata not found");
|
||
|
|
}
|
||
|
|
|
||
|
|
if (typeof sectionMetadata.size.loc === "undefined") {
|
||
|
|
throw new Error("SectionMetadata " + section + " has no loc");
|
||
|
|
} // keep old node location to be overriden
|
||
|
|
|
||
|
|
|
||
|
|
var start = sectionMetadata.size.loc.start.column;
|
||
|
|
var end = sectionMetadata.size.loc.end.column;
|
||
|
|
var newSectionSize = sectionMetadata.size.value + deltaBytes;
|
||
|
|
var newBytes = encodeU32(newSectionSize);
|
||
|
|
/**
|
||
|
|
* update AST
|
||
|
|
*/
|
||
|
|
|
||
|
|
sectionMetadata.size.value = newSectionSize;
|
||
|
|
var oldu32EncodedLen = end - start;
|
||
|
|
var newu32EncodedLen = newBytes.length; // the new u32 has a different encoded length
|
||
|
|
|
||
|
|
if (newu32EncodedLen !== oldu32EncodedLen) {
|
||
|
|
var deltaInSizeEncoding = newu32EncodedLen - oldu32EncodedLen;
|
||
|
|
sectionMetadata.size.loc.end.column = start + newu32EncodedLen;
|
||
|
|
deltaBytes += deltaInSizeEncoding; // move the vec size pointer size the section size is now smaller
|
||
|
|
|
||
|
|
sectionMetadata.vectorOfSize.loc.start.column += deltaInSizeEncoding;
|
||
|
|
sectionMetadata.vectorOfSize.loc.end.column += deltaInSizeEncoding;
|
||
|
|
} // Once we hit our section every that is after needs to be shifted by the delta
|
||
|
|
|
||
|
|
|
||
|
|
var encounteredSection = false;
|
||
|
|
traverse(ast, {
|
||
|
|
SectionMetadata: function SectionMetadata(path) {
|
||
|
|
if (path.node.section === section) {
|
||
|
|
encounteredSection = true;
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (encounteredSection === true) {
|
||
|
|
shiftSection(ast, path.node, deltaBytes);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
return overrideBytesInBuffer(uint8Buffer, start, end, newBytes);
|
||
|
|
}
|
||
|
|
export function resizeSectionVecSize(ast, uint8Buffer, section, deltaElements) {
|
||
|
|
var sectionMetadata = getSectionMetadata(ast, section);
|
||
|
|
|
||
|
|
if (typeof sectionMetadata === "undefined") {
|
||
|
|
throw new Error("Section metadata not found");
|
||
|
|
}
|
||
|
|
|
||
|
|
if (typeof sectionMetadata.vectorOfSize.loc === "undefined") {
|
||
|
|
throw new Error("SectionMetadata " + section + " has no loc");
|
||
|
|
} // Section has no vector
|
||
|
|
|
||
|
|
|
||
|
|
if (sectionMetadata.vectorOfSize.value === -1) {
|
||
|
|
return uint8Buffer;
|
||
|
|
} // keep old node location to be overriden
|
||
|
|
|
||
|
|
|
||
|
|
var start = sectionMetadata.vectorOfSize.loc.start.column;
|
||
|
|
var end = sectionMetadata.vectorOfSize.loc.end.column;
|
||
|
|
var newValue = sectionMetadata.vectorOfSize.value + deltaElements;
|
||
|
|
var newBytes = encodeU32(newValue); // Update AST
|
||
|
|
|
||
|
|
sectionMetadata.vectorOfSize.value = newValue;
|
||
|
|
sectionMetadata.vectorOfSize.loc.end.column = start + newBytes.length;
|
||
|
|
return overrideBytesInBuffer(uint8Buffer, start, end, newBytes);
|
||
|
|
}
|