"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.applyOperations = applyOperations;
var _wasmGen = require("@webassemblyjs/wasm-gen");
var _encoder = require("@webassemblyjs/wasm-gen/lib/encoder");
var _ast = require("@webassemblyjs/ast");
var _helperWasmSection = require("@webassemblyjs/helper-wasm-section");
var _helperBuffer = require("@webassemblyjs/helper-buffer");
var _helperWasmBytecode = require("@webassemblyjs/helper-wasm-bytecode");
function _sliceIterator(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; }
function _slicedToArray(arr, i) { if (Array.isArray(arr)) { return arr; } else if (Symbol.iterator in Object(arr)) { return _sliceIterator(arr, i); } else { throw new TypeError("Invalid attempt to destructure non-iterable instance"); } }
function shiftLocNodeByDelta(node, delta) {
(0, _ast.assertHasLoc)(node); // $FlowIgnore: assertHasLoc ensures that
node.loc.start.column += delta; // $FlowIgnore: assertHasLoc ensures that
node.loc.end.column += delta;
}
function applyUpdate(ast, uint8Buffer, _ref) {
var _ref2 = _slicedToArray(_ref, 2),
oldNode = _ref2[0],
newNode = _ref2[1];
var deltaElements = 0;
(0, _ast.assertHasLoc)(oldNode);
var sectionName = (0, _helperWasmBytecode.getSectionForNode)(newNode);
var replacementByteArray = (0, _wasmGen.encodeNode)(newNode);
/**
* Replace new node as bytes
*/
uint8Buffer = (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, // $FlowIgnore: assertHasLoc ensures that
oldNode.loc.start.column, // $FlowIgnore: assertHasLoc ensures that
oldNode.loc.end.column, replacementByteArray);
/**
* Update function body size if needed
*/
if (sectionName === "code") {
// Find the parent func
(0, _ast.traverse)(ast, {
Func: function Func(_ref3) {
var node = _ref3.node;
var funcHasThisIntr = node.body.find(function (n) {
return n === newNode;
}) !== undefined; // Update func's body size if needed
if (funcHasThisIntr === true) {
// These are the old functions locations informations
(0, _ast.assertHasLoc)(node);
var oldNodeSize = (0, _wasmGen.encodeNode)(oldNode).length;
var bodySizeDeltaBytes = replacementByteArray.length - oldNodeSize;
if (bodySizeDeltaBytes !== 0) {
var newValue = node.metadata.bodySize + bodySizeDeltaBytes;
var newByteArray = (0, _encoder.encodeU32)(newValue); // function body size byte
// FIXME(sven): only handles one byte u32
var start = node.loc.start.column;
var end = start + 1;
uint8Buffer = (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, start, end, newByteArray);
}
}
}
});
}
/**
* Update section size
*/
var deltaBytes = replacementByteArray.length - ( // $FlowIgnore: assertHasLoc ensures that
oldNode.loc.end.column - oldNode.loc.start.column); // Init location informations
newNode.loc = {
start: {
line: -1,
column: -1
},
end: {
line: -1,
column: -1
}
}; // Update new node end position
// $FlowIgnore: assertHasLoc ensures that
newNode.loc.start.column = oldNode.loc.start.column; // $FlowIgnore: assertHasLoc ensures that
newNode.loc.end.column = // $FlowIgnore: assertHasLoc ensures that
oldNode.loc.start.column + replacementByteArray.length;
return {
uint8Buffer: uint8Buffer,
deltaBytes: deltaBytes,
deltaElements: deltaElements
};
}
function applyDelete(ast, uint8Buffer, node) {
var deltaElements = -1; // since we removed an element
(0, _ast.assertHasLoc)(node);
var sectionName = (0, _helperWasmBytecode.getSectionForNode)(node);
if (sectionName === "start") {
var sectionMetadata = (0, _ast.getSectionMetadata)(ast, "start");
/**
* The start section only contains one element,
* we need to remove the whole section
*/
uint8Buffer = (0, _helperWasmSection.removeSections)(ast, uint8Buffer, "start");
var _deltaBytes = -(sectionMetadata.size.value + 1);
/* section id */
return {
uint8Buffer: uint8Buffer,
deltaBytes: _deltaBytes,
deltaElements: deltaElements
};
} // replacement is nothing
var replacement = [];
uint8Buffer = (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, // $FlowIgnore: assertHasLoc ensures that
node.loc.start.column, // $FlowIgnore: assertHasLoc ensures that
node.loc.end.column, replacement);
/**
* Update section
*/
// $FlowIgnore: assertHasLoc ensures that
var deltaBytes = -(node.loc.end.column - node.loc.start.column);
return {
uint8Buffer: uint8Buffer,
deltaBytes: deltaBytes,
deltaElements: deltaElements
};
}
function applyAdd(ast, uint8Buffer, node) {
var deltaElements = +1; // since we added an element
var sectionName = (0, _helperWasmBytecode.getSectionForNode)(node);
var sectionMetadata = (0, _ast.getSectionMetadata)(ast, sectionName); // Section doesn't exists, we create an empty one
if (typeof sectionMetadata === "undefined") {
var res = (0, _helperWasmSection.createEmptySection)(ast, uint8Buffer, sectionName);
uint8Buffer = res.uint8Buffer;
sectionMetadata = res.sectionMetadata;
}
/**
* check that the expressions were ended
*/
if ((0, _ast.isFunc)(node)) {
// $FlowIgnore
var body = node.body;
if (body.length === 0 || body[body.length - 1].id !== "end") {
throw new Error("expressions must be ended");
}
}
if ((0, _ast.isGlobal)(node)) {
// $FlowIgnore
var body = node.init;
if (body.length === 0 || body[body.length - 1].id !== "end") {
throw new Error("expressions must be ended");
}
}
/**
* Add nodes
*/
var newByteArray = (0, _wasmGen.encodeNode)(node); // The size of the section doesn't include the storage of the size itself
// we need to manually add it here
var start = (0, _ast.getEndOfSection)(sectionMetadata);
var end = start;
/**
* Update section
*/
var deltaBytes = newByteArray.length;
uint8Buffer = (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, start, end, newByteArray);
node.loc = {
start: {
line: -1,
column: start
},
end: {
line: -1,
column: start + deltaBytes
}
}; // for func add the additional metadata in the AST
if (node.type === "Func") {
// the size is the first byte
// FIXME(sven): handle LEB128 correctly here
var bodySize = newByteArray[0];
node.metadata = {
bodySize: bodySize
};
}
if (node.type !== "IndexInFuncSection") {
(0, _ast.orderedInsertNode)(ast.body[0], node);
}
return {
uint8Buffer: uint8Buffer,
deltaBytes: deltaBytes,
deltaElements: deltaElements
};
}
function applyOperations(ast, uint8Buffer, ops) {
ops.forEach(function (op) {
var state;
var sectionName;
switch (op.kind) {
case "update":
state = applyUpdate(ast, uint8Buffer, [op.oldNode, op.node]);
sectionName = (0, _helperWasmBytecode.getSectionForNode)(op.node);
break;
case "delete":
state = applyDelete(ast, uint8Buffer, op.node);
sectionName = (0, _helperWasmBytecode.getSectionForNode)(op.node);
break;
case "add":
state = applyAdd(ast, uint8Buffer, op.node);
sectionName = (0, _helperWasmBytecode.getSectionForNode)(op.node);
break;
default:
throw new Error("Unknown operation");
}
/**
* Resize section vec size.
* If the length of the LEB-encoded size changes, this can change
* the byte length of the section and the offset for nodes in the
* section. So we do this first before resizing section byte size
* or shifting following operations' nodes.
*/
if (state.deltaElements !== 0 && sectionName !== "start") {
var oldBufferLength = state.uint8Buffer.length;
state.uint8Buffer = (0, _helperWasmSection.resizeSectionVecSize)(ast, state.uint8Buffer, sectionName, state.deltaElements); // Infer bytes added/removed by comparing buffer lengths
state.deltaBytes += state.uint8Buffer.length - oldBufferLength;
}
/**
* Resize section byte size.
* If the length of the LEB-encoded size changes, this can change
* the offset for nodes in the section. So we do this before
* shifting following operations' nodes.
*/
if (state.deltaBytes !== 0 && sectionName !== "start") {
var _oldBufferLength = state.uint8Buffer.length;
state.uint8Buffer = (0, _helperWasmSection.resizeSectionByteSize)(ast, state.uint8Buffer, sectionName, state.deltaBytes); // Infer bytes added/removed by comparing buffer lengths
state.deltaBytes += state.uint8Buffer.length - _oldBufferLength;
}
/**
* Shift following operation's nodes
*/
if (state.deltaBytes !== 0) {
ops.forEach(function (op) {
// We don't need to handle add ops, they are positioning independent
switch (op.kind) {
case "update":
shiftLocNodeByDelta(op.oldNode, state.deltaBytes);
break;
case "delete":
shiftLocNodeByDelta(op.node, state.deltaBytes);
break;
}
});
}
uint8Buffer = state.uint8Buffer;
});
return uint8Buffer;
}