ethers.js/packages/asm/src.ts/assembler.ts
2020-01-30 21:41:03 -05:00

1041 lines
31 KiB
TypeScript

"use strict";
// @TODO:
// - PIC
// - warn on opcode non-function iff parameters
// - warn return/revert non-empty, comment ; !assert(+1 @extra)
// - $$
// - In JS add config (positionIndependent)
// - When checking name collisions, verify no collision in javascript
import { dirname, resolve } from "path";
import _module from "module";
import vm from "vm";
import { ethers } from "ethers";
import { Opcode } from "./opcodes";
import { parse as _parse, parser as _parser } from "./_parser";
import { version } from "./_version";
const logger = new ethers.utils.Logger(version);
const Guard = { };
function hexConcat(values: Array<Opcode | ethers.utils.BytesLike>): string {
return ethers.utils.hexlify(ethers.utils.concat(values.map((v) => {
if (v instanceof Opcode) { return [ v.value ]; }
return v;
})));
}
function repeat(char: string, length: number): string {
let result = char;
while (result.length < length) { result += result; }
return result.substring(0, length);
}
class Script {
readonly filename: string;
readonly context: any;
readonly contextObject: any;
private _context: { context: any };
constructor(filename: string, callback: (name: string, context: any) => any) {
ethers.utils.defineReadOnly(this, "filename", filename);
ethers.utils.defineReadOnly(this, "contextObject", this._baseContext(callback));
ethers.utils.defineReadOnly(this, "context", vm.createContext(this.contextObject));
}
_baseContext(callback: (name: string, context: any) => any): any {
return new Proxy({
__filename: this.filename,
__dirname: dirname(this.filename),
console: console,
Uint8Array: Uint8Array,
ethers: ethers,
utils: ethers.utils,
BigNumber: ethers.BigNumber,
arrayify: ethers.utils.arrayify,
concat: hexConcat,
hexlify: ethers.utils.hexlify,
zeroPad: function(value: ethers.utils.BytesLike, length: number) {
return ethers.utils.hexlify(ethers.utils.zeroPad(value, length));
},
id: ethers.utils.id,
keccak256: ethers.utils.keccak256,
namehash: ethers.utils.namehash,
sha256: ethers.utils.sha256,
parseEther: ethers.utils.parseEther,
formatEther: ethers.utils.formatEther,
parseUnits: ethers.utils.parseUnits,
formatUnits: ethers.utils.formatUnits,
randomBytes: function(length: number): string {
return ethers.utils.hexlify(ethers.utils.randomBytes(length));
},
toUtf8Bytes: ethers.utils.toUtf8Bytes,
toUtf8String: ethers.utils.toUtf8String,
formatBytes32String: ethers.utils.formatBytes32String,
parseBytes32String: ethers.utils.parseBytes32String,
Opcode: Opcode,
sighash: function(signature: string): string {
return ethers.utils.id(ethers.utils.FunctionFragment.from(signature).format()).substring(0, 10);
},
topichash: function(signature: string): string {
return ethers.utils.id(ethers.utils.EventFragment.from(signature).format());
},
assemble: assemble,
disassemble: disassemble
}, {
get: (obj: any, key: string): any => {
if (obj[key]) { return obj[key]; }
if (!callback) { return undefined; }
return callback(key, this._context.context);
}
});
}
async evaluate(code: string, context?: any): Promise<string> {
if (this._context) { throw new Error("evaluation collision"); }
this._context = { context: context };
const script = new vm.Script(code, { filename: this.filename });
let result = script.runInContext(this.context);
if (result instanceof Promise) {
result = await result;
}
this._context = null;
return result;
}
}
let nextTag = 1;
export type Location = {
offset: number;
length: number;
source: string;
};
export type AssembleVisitFunc = (node: Node, bytecode: string) => void;
export type VisitFunc = (node: Node) => void;
export abstract class Node {
readonly tag: string;
readonly location: Location;
readonly warnings: Array<string>;
constructor(guard: any, location: Location, options: { [ key: string ]: any }) {
if (guard !== Guard) { throw new Error("cannot instantiate class"); }
ethers.utils.defineReadOnly(this, "location", location);
ethers.utils.defineReadOnly(this, "tag", `node-${ nextTag++ }-${ this.constructor.name }`);
ethers.utils.defineReadOnly(this, "warnings", [ ]);
for (const key in options) {
ethers.utils.defineReadOnly(this, key, options[key]);
}
}
// Note: EVERY node must call assemble with `this`, even if only with
// the bytes "0x" to trigger the offset and bytecode checks
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
visit(this, "0x");
assembler.end(this);
}
children(): Array<Node> {
return [ ];
}
visit(visit: VisitFunc): void {
visit(this);
}
static from(options: any): Node {
const Factories: { [ type: string ]: { from: (options: any) => Node }} = {
data: DataNode,
decimal: LiteralNode,
eval: EvaluationNode,
exec: ExecutionNode,
hex: LiteralNode,
label: LabelNode,
length: LinkNode,
offset: LinkNode,
opcode: OpcodeNode,
scope: ScopeNode,
};
const factory = Factories[options.type];
if (!factory) { throw new Error("uknown type: " + options.type); }
return factory.from(options);
}
}
export abstract class CodeNode extends Node { }
export abstract class ValueNode extends CodeNode { }
function pushLiteral(value: ethers.utils.BytesLike | ethers.utils.Hexable | number) {
// Convert value into a hexstring
const hex = ethers.utils.hexlify(value);
if (hex === "0x") {
throw new Error("invalid literal: 0x");
}
// Make sure it will fit into a push
const length = ethers.utils.hexDataLength(hex);
if (length === 0 || length > 32) { throw new Error(`literal out of range: ${ hex }`); }
return hexConcat([ Opcode.from("PUSH" + String(length)), hex ]);
}
export class LiteralNode extends ValueNode {
readonly value: string;
readonly verbatim: boolean;
constructor(guard: any, location: Location, value: string, verbatim: boolean) {
super(guard, location, { value, verbatim });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
if (this.verbatim) {
if (this.value.substring(0, 2) === "0x") {
visit(this, this.value);
} else {
visit(this, ethers.BigNumber.from(this.value).toHexString());
}
} else {
visit(this, pushLiteral(ethers.BigNumber.from(this.value)));
}
assembler.end(this);
}
static from(options: any): LiteralNode {
if (options.type !== "hex" && options.type !== "decimal") { throw new Error("expected hex or decimal type"); }
return new LiteralNode(Guard, options.loc, options.value, !!options.verbatim);
}
}
export class LinkNode extends ValueNode {
readonly type: string;
readonly label: string;
constructor(guard: any, location: Location, type: string, label: string) {
super(guard, location, { type, label });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
let value: number = null;
const target = assembler.getTarget(this.label);
if (target instanceof LabelNode) {
if (this.type === "offset") {
//value = assembler.getOffset(this.label);
value = (<number>(assembler.getLinkValue(target, this)));
}
} else {
const result = (<DataSource>(assembler.getLinkValue(target, this)));
if (this.type === "offset") {
//value = assembler.getOffset(this.label);
value = result.offset;
} else if (this.type === "length") {
//value = assembler.getLength(this.label);
value = result.length;
}
}
if (value == null) {
throw new Error("labels can only be targetted as offsets");
}
visit(this, pushLiteral(value));
assembler.end(this);
}
static from(options: any): LinkNode {
// @TODO: Verify type is offset or link...
return new LinkNode(Guard, options.loc, options.type, options.label);
}
}
export class OpcodeNode extends ValueNode {
readonly opcode: Opcode;
readonly operands: Array<ValueNode>;
constructor(guard: any, location: Location, opcode: Opcode, operands: Array<ValueNode>) {
super(guard, location, { opcode, operands });
if (opcode.isPush()) {
this.warnings.push("the PUSH opcode modifies program flow - use literals instead");
}
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
// Compute the bytecode in reverse stack order
for (let i = this.operands.length - 1; i >= 0; i--) {
await this.operands[i].assemble(assembler, visit);
}
// Append this opcode
visit(this, ethers.utils.hexlify(this.opcode.value));
assembler.end(this);
}
children(): Array<Node> {
return this.operands;
}
visit(visit: VisitFunc): void {
for (let i = this.operands.length - 1; i >= 0; i--) {
this.operands[i].visit(visit);
}
visit(this);
}
static from(options: any): OpcodeNode {
if (options.type !== "opcode") { throw new Error("expected opcode type"); }
const opcode = Opcode.from(options.mnemonic);
if (!opcode) { throw new Error("unknown opcode: " + options.mnemonic); }
// Using the function syntax will check the operand count
if (!options.bare) {
if (opcode.mnemonic === "POP" && options.operands.length === 0) {
// This is ok... Pop has a delta of 0, but without operands
} else if (options.operands.length !== opcode.delta) {
throw new Error(`opcode ${ opcode.mnemonic } expects ${ opcode.delta } operands`);
}
}
const operands = Object.freeze(options.operands.map((o: any) => {
const operand = Node.from(o);
if (!(operand instanceof ValueNode)) {
throw new Error("invalid operand");
}
return operand;
}));
return new OpcodeNode(Guard, options.loc, opcode, operands);
}
}
export abstract class LabelledNode extends CodeNode {
readonly name: string;
constructor(guard: any, location: Location, name: string, values?: { [ key: string ]: any }) {
values = ethers.utils.shallowCopy(values || { });
values.name = name;
super(guard, location, values);
}
}
export class LabelNode extends LabelledNode {
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
visit(this, ethers.utils.hexlify(Opcode.from("JUMPDEST").value));
assembler.end(this);
}
static from(options: any): LabelNode {
if (options.type !== "label") { throw new Error("expected label type"); }
return new LabelNode(Guard, options.loc, options.name);
}
}
export class DataNode extends LabelledNode {
readonly data: Array<ValueNode>;
constructor(guard: any, location: Location, name: string, data: string) {
super(guard, location, name, { data });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
for (let i = 0; i < this.data.length; i++) {
await this.data[i].assemble(assembler, visit);
}
// We pad data if is contains PUSH opcodes that would overrun
// the data, which could eclipse valid operations (since the
// VM won't execute or jump within PUSH operations)
const bytecode = ethers.utils.arrayify(assembler.getPendingBytecode(this));
// Replay the data as bytecode, skipping PUSH data
let i = 0;
while (i < bytecode.length) {
const opcode = Opcode.from(bytecode[i++]);
if (opcode) {
i += opcode.isPush();
}
}
// The amount we overshot the data by is how much padding we need
const padding = new Uint8Array(i - bytecode.length);
// What makes more sense? INVALID or 0 (i.e. STOP)?
//padding.fill(Opcode.from("INVALID").value);
padding.fill(0);
visit(this, ethers.utils.hexlify(padding))
assembler.end(this);
}
children(): Array<Node> {
return this.data;
}
visit(visit: VisitFunc): void {
visit(this);
for (let i = 0; i < this.data.length; i++) {
this.data[i].visit(visit);
}
}
static from(options: any): DataNode {
if (options.type !== "data") { throw new Error("expected data type"); }
return new DataNode(Guard, options.loc, options.name, Object.freeze(options.data.map((d: any) => Node.from(d))));
}
}
export class EvaluationNode extends ValueNode {
readonly script: string;
readonly verbatim: boolean;
constructor(guard: any, location: Location, script: string, verbatim: boolean) {
super(guard, location, { script, verbatim });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
const result: any = await assembler.evaluate(this.script, this);
if (this.verbatim) {
if (typeof(result) === "number") {
visit(this, ethers.BigNumber.from(result).toHexString());
} else {
visit(this, ethers.utils.hexlify(result));
}
} else {
visit(this, pushLiteral(result));
}
assembler.end(this);
}
static from(options: any): EvaluationNode {
if (options.type !== "eval") { throw new Error("expected eval type"); }
return new EvaluationNode(Guard, options.loc, options.script, !!options.verbatim);
}
}
export class ExecutionNode extends CodeNode {
readonly script: string;
constructor(guard: any, location: Location, script: string) {
super(guard, location, { script });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
await assembler.evaluate(this.script, this);
assembler.end(this);
}
static from(options: any): ExecutionNode {
if (options.type !== "exec") { throw new Error("expected exec type"); }
return new ExecutionNode(Guard, options.loc, options.script);
}
}
export class ScopeNode extends LabelledNode {
readonly statements: Array<Node>;
constructor(guard: any, location: Location, name: string, statements: Array<Node>) {
super(guard, location, name, { statements });
}
async assemble(assembler: Assembler, visit: AssembleVisitFunc): Promise<void> {
assembler.start(this);
visit(this, "0x");
for (let i = 0; i < this.statements.length; i++) {
await this.statements[i].assemble(assembler, visit);
}
assembler.end(this);
}
children(): Array<Node> {
return this.statements;
}
visit(visit: VisitFunc): void {
visit(this);
for (let i = 0; i < this.statements.length; i++) {
this.statements[i].visit(visit);
}
}
static from(options: any): ScopeNode {
if (options.type !== "scope") { throw new Error("expected scope type"); }
return new ScopeNode(Guard, options.loc, options.name, Object.freeze(options.statements.map((s: any) => Node.from(s))));
}
}
type _Location = {
first_line: number;
last_line: number;
first_column: number;
last_column: number;
}
export function parse(code: string): Node {
// Since jison allows \n, \r or \r\n line endings, we need some
// twekaing to get the correct position
const lines: Array<{ line: string, offset: number }> = [ ];
let offset = 0;
code.split(/(\r\n?|\n)/g).forEach((clump, index) => {
if (index % 2) {
lines[lines.length - 1].line += clump;
} else {
lines.push({ line: clump, offset: offset });
}
offset += clump.length;
});
// Add a mock-EOF to the end of the file so we don't out-of-bounds
// on the last character
if (lines.length) {
lines[lines.length - 1].line += "\n";
}
// Givens a line (1 offset) and column (0 offset) return the byte offset
const getOffset = function(line: number, column: number): number {
const info = lines[line - 1];
console.log(line, column, info);
if (!info || column >= info.line.length) { throw new Error("out of range"); }
return info.offset + column;
};
// We use this in the _parser to convert locations to source
_parser.yy._ethersLocation = function(loc?: _Location): Location {
// The _ scope should call with null to get the full source
if (loc == null) {
return Object.freeze({
offset: 0,
length: code.length,
source: code
});
}
const offset = getOffset(loc.first_line, loc.first_column);
const end = getOffset(loc.last_line, loc.last_column);
return Object.freeze({
offset: offset,
length: (end - offset),
source: code.substring(offset, end)
});
};
const result = Node.from(_parse(code));
// Nuke the source code lookup callback
_parser.yy._ethersLocation = null;
return result;
}
export type Operation = {
opcode: Opcode;
offset: number;
pushValue?: string;
};
export interface Bytecode extends Array<Operation> {
getOperation(offset: number): Operation;
}
export function disassemble(bytecode: string): Bytecode {
const ops: Array<Operation> = [ ];
const offsets: { [ offset: number ]: Operation } = { };
const bytes = ethers.utils.arrayify(bytecode, { allowMissingPrefix: true });
let i = 0;
let oob = false;
while (i < bytes.length) {
let opcode = Opcode.from(bytes[i]);
if (!opcode) {
opcode = new Opcode(`unknown (${ ethers.utils.hexlify(bytes[i]) })`, bytes[i], 0, 0);
} else if (oob && opcode.mnemonic === "JUMPDEST") {
opcode = new Opcode(`JUMPDEST (invalid; OOB!!)`, bytes[i], 0, 0);
}
const op: Operation = {
opcode: opcode,
offset: i
};
offsets[i] = op;
ops.push(op);
i++;
const push = opcode.isPush();
if (push) {
const data = ethers.utils.hexlify(bytes.slice(i, i + push));
if (ethers.utils.hexDataLength(data) === push) {
op.pushValue = data;
i += push;
} else {
oob = true;
}
}
}
(<Bytecode>ops).getOperation = function(offset: number): Operation {
return (offsets[offset] || null);
};
return (<Bytecode>ops);
}
export function formatBytecode(bytecode: Array<Operation>): string {
const lines: Array<string> = [ ];
bytecode.forEach((op) => {
const opcode = op.opcode;
let offset = ethers.utils.hexZeroPad(ethers.utils.hexlify(op.offset), 2);
if (opcode.isValidJumpDest()) {
offset += "*";
} else {
offset += " ";
}
let operation = opcode.mnemonic;
const push = opcode.isPush();
if (push) {
if (op.pushValue) {
operation = op.pushValue + `${ repeat(" ", 65 - op.pushValue.length) }; ${ operation } `;
} else {
operation += `${ repeat(" ", 65 - operation.length) }; OOB!! `;
}
}
lines.push(`${ offset.substring(2) }: ${ operation }`);
});
return lines.join("\n");
}
interface DataSource extends Array<number> {
readonly offset: number;
}
type NodeState = {
node: Node;
offset: number;
bytecode: string;
pending: string;
object?: number | DataSource;
};
export type AssemblerOptions = {
filename?: string;
retry?: number;
positionIndependentCode?: boolean;
defines?: { [ name: string ]: any };
};
// @TODO: Rename to Assembler?
class Assembler {
readonly root: Node;
readonly nodes: { [ tag: string ]: NodeState };
readonly labels: { [ name: string ]: LabelledNode };
readonly filename: string;
readonly positionIndependentCode: boolean;
readonly retry: number;
readonly defines: { [ name: string ]: any };
private _stack: Array<Node>;
private _parents: { [ tag: string ]: Node };
private _script: Script;
private _changed: boolean;
constructor(root: Node, options: AssemblerOptions) {
ethers.utils.defineReadOnly(this, "positionIndependentCode", !!options.positionIndependentCode);
ethers.utils.defineReadOnly(this, "retry", ((options.retry != null) ? options.retry: 512));
ethers.utils.defineReadOnly(this, "filename", resolve(options.filename || "./contract.asm"));
ethers.utils.defineReadOnly(this, "defines", Object.freeze(options.defines || { }));
ethers.utils.defineReadOnly(this, "root", root);
const nodes: { [ tag: string ]: NodeState } = { };
const labels: { [ name: string ]: Node } = { };
const parents: { [ tag: string ]: Node } = { };
// Link labels to their target node
root.visit((node) => {
nodes[node.tag] = {
node: node,
offset: 0x0,
bytecode: "0x",
pending: "0x"
};
if (node instanceof LabelledNode) {
// Check for duplicate labels
if (labels[node.name]) {
logger.throwError(
("duplicate label: " + node.name),
ethers.utils.Logger.errors.UNSUPPORTED_OPERATION,
{ }
);
}
labels[node.name] = node;
}
});
root.visit((node) => {
// Check all labels exist
if (node instanceof LinkNode) {
const target = labels[node.label];
if (!target) {
logger.throwError(
("missing label: " + node.label),
ethers.utils.Logger.errors.UNSUPPORTED_OPERATION,
{ }
);
}
}
// Build the parent structure
node.children().forEach((child) => {
parents[child.tag] = node;
});
});
ethers.utils.defineReadOnly(this, "labels", Object.freeze(labels));
ethers.utils.defineReadOnly(this, "nodes", Object.freeze(nodes));
ethers.utils.defineReadOnly(this, "_parents", Object.freeze(parents));
ethers.utils.defineReadOnly(this, "_stack", [ ]);
this.reset();
}
get changed(): boolean {
return this._changed;
}
// Link operations
getTarget(name: string): LabelledNode {
return this.labels[name];
}
// Reset the assmebler for another run with updated values
reset(): void {
this._changed = false;
for (const tag in this.nodes) {
delete this.nodes[tag].object;
}
this._script = new Script(this.filename, (name: string, context: any) => {
return this.get(name, context);
});
}
evaluate(script: string, source: Node): Promise<any> {
return this._script.evaluate(script, source);
}
start(node: Node): void {
this._stack.push(node);
const info = this.nodes[node.tag];
info.pending = "0x";
}
end(node: Node): void {
if (this._stack.pop() !== node) {
throw new Error("missing push/pop pair");
}
const info = this.nodes[node.tag];
if (info.pending !== info.bytecode) {
this._didChange();
}
info.bytecode = info.pending;
}
getPendingBytecode(node: Node): string {
return this.nodes[node.tag].pending;
}
_appendBytecode(bytecode: string) {
this._stack.forEach((node) => {
const info = this.nodes[node.tag];
info.pending = hexConcat([ info.pending, bytecode ]);
});
}
getAncestor<T = Node>(node: Node, cls: { new(...args: any[]): T }): T {
node = this._parents[node.tag];
while (node) {
if (node instanceof cls) { return node; }
node = this._parents[node.tag];
}
return null;
}
getLinkValue(target: LabelledNode, source: Node): number | DataSource {
const sourceScope: ScopeNode = ((source instanceof ScopeNode) ? source: this.getAncestor<ScopeNode>(source, ScopeNode));
const targetScope: ScopeNode = ((target instanceof ScopeNode) ? target: this.getAncestor<ScopeNode>(target, ScopeNode));
if (target instanceof LabelNode) {
// Label offset (e.g. "@foo:"); accessible only within its direct scope
//const scope = this.getAncestor(source, Scope);
if (targetScope !== sourceScope) {
throw new Error(`cannot access ${ target.name } from ${ source.tag }`);
}
// Return the offset relative to its scope
let offset = this.nodes[target.tag].offset - this.nodes[targetScope.tag].offset;
// Offsets are wrong; but we should finish this run and then try again
if (offset < 0) {
offset = 0;
this._didChange();
}
return offset;
}
const info = this.nodes[target.tag];
// Return the offset is relative to its scope
const bytes = Array.prototype.slice.call(ethers.utils.arrayify(info.bytecode));
bytes.ast = target;
bytes.source = target.location.source;
if (!((target instanceof DataNode) || (target instanceof ScopeNode))) {
throw new Error("invalid link value lookup");
}
// Check that target is any descendant (or self) of the source scope
let safeOffset = (sourceScope == targetScope);
if (!safeOffset) {
sourceScope.visit((node) => {
if (node === targetScope) { safeOffset = true; }
});
}
// Not safe to access the offset; this will fault if anything tries.
if (!safeOffset) {
Object.defineProperty(bytes, "offset", {
get: function() { throw new Error(`cannot access ${ target.name }.offset from ${ source.tag }`); }
});
}
// Add the offset relative to the scope; unless the offset has
// been marked as invalid, in which case accessing it will fail
if (safeOffset) {
bytes.offset = info.offset - this.nodes[sourceScope.tag].offset;
// Offsets are wqrong; but we should finish this run and then try again
if (bytes.offset < 0) {
bytes.offset = 0;
this._didChange();
}
}
return Object.freeze(bytes);
}
get(name: string, source: Node): any {
if (name === "defines") {
return this.defines;
}
const node = this.labels[name];
if (!node) { return undefined; }
const info = this.nodes[node.tag];
if (info.object == null) {
info.object = this.getLinkValue(node, source);
}
return info.object;
}
_didChange(): void {
this._changed = true;
}
async _assemble(): Promise<string> {
let offset = 0;
const bytecodes: Array<string> = [ ];
await this.root.assemble(this, (node, bytecode) => {
const state = this.nodes[node.tag];
// Things have moved; we will need to try again
if (state.offset !== offset) {
state.offset = offset;
this._didChange();
}
this._appendBytecode(bytecode);
bytecodes.push(bytecode);
// The bytecode has changed; we will need to try again
//if (state.bytecode !== bytecode) {
// state.bytecode = bytecode;
// this._didChange();
//}
offset += ethers.utils.hexDataLength(bytecode);
});
return hexConcat(bytecodes);
}
async assemble(): Promise<string> {
// Continue re-evaluating the bytecode until a stable set of
// offsets, length and values are reached.
let bytecode = await this._assemble();
for (let i = 0; i < this.retry; i++) {
// Regenerate the code with the updated assembler values
this.reset();
const adjusted = await this._assemble();
// Generated bytecode is stable!! :)
if (!this.changed) {
console.log(`Assembled in ${ i } attempts`);
return bytecode;
}
// Try again...
bytecode = adjusted;
}
// This should not happen; something is wrong with the grammar
// or missing enter/exit call in assemble
if (this._stack.length !== 0) {
throw new Error("bad AST");
}
return logger.throwError(
`unable to assemble; ${ this.retry } attempts failed to generate stable bytecode`,
ethers.utils.Logger.errors.UNKNOWN_ERROR,
{ }
);
}
}
export async function assemble(ast: Node, options?: AssemblerOptions): Promise<string> {
const assembler = new Assembler(ast, options || { });
return assembler.assemble();
}
/*
export const code = `; SimpleStore (uint)
; Set the inital value of 42
sstore(0, 42)
; Init code to deploy myContract
codecopy(0, $myContract, #myContract)
return(0, #myContract)
@myContract {
; Non-payable
jumpi($error, callvalue)
; Get the Sighash
shr({{= 256 - 32 }}, calldataload(0))
; getValue()
dup1
{{= sighash("getValue()") }}
jumpi($getValue, eq)
; setValue(uint)
dup1
{{= sighash("setValue(uint)") }}
jumpi($setValue, eq)
; No matching signature
@error:
revert(0, 0)
@getValue:
mstore(0, sload(0))
return (0, 32)
@setValue:
; Make sure we have exactly a uint
jumpi($error, iszero(eq(calldatasize, 36)))
; Store the value
sstore(0, calldataload(4))
return (0, 0)
@checksum[
{{= (defines.checksum ? concat([ Opcode.from("PUSH32"), id(_.source) ]): "0x") }}
]
}`;
(async function() {
console.log("AST");
const ast = parse(code);
console.dir(ast, { depth: null });
const asm = await assemble(ast, { defines: { checksum: true } } );
console.log("ASSEMBLE\n", asm);
console.log("OPCODES\n" + formatBytecode(disassemble(asm)));
})();
*/