fix: better isLastInstruction logic for code with DEBUGMARK, fix skipRefs mode exception for if recompilation

package.json

@@ -1,6 +1,6 @@
 {
     "name": "ton-assembly",
-    "version": "0.3.1",
+    "version": "0.3.2",
     "description": "TON assembler and disassembler",
     "author": "TON Studio & TON Core",
     "repository": {
@@ -26,12 +26,6 @@
     ],
     "main": "dist/index.js",
     "types": "dist/index.d.ts",
-    "exports": {
-        ".": {
-            "types": "./dist/index.d.ts",
-            "default": "./dist/index.js"
-        }
-    },
     "sideEffects": false,
     "scripts": {
         "build": "tsc --declaration",

src/runtime/compile.ts

@@ -7,6 +7,37 @@ import {matchingRule} from "./layout"
 import {IF, IFELSE, IFJMP, IFNOT, IFNOTJMP, PUSHCONT, PUSHCONT_SHORT} from "./types"
 import type {StoreOptions} from "./util"
 
+function isLastInstruction(index: number, instructions: Instr[]) {
+    if (index === instructions.length - 1) {
+        return true
+    }
+
+    if (instructions[index + 1]?.$ !== "DEBUGMARK") {
+        // Fast path, if:
+        // POPCTR
+        // ADD
+        //
+        // instruction is not the last one
+        return false
+    }
+
+    // if:
+    // POPCTR
+    // DEBUGMARK
+    //
+    // check that all remaining instructions are DEBUGMARK
+
+    for (let i = index + 1; i < instructions.length; i++) {
+        const instruction = instructions[i]
+        if (instruction?.$ !== "DEBUGMARK") {
+            // found non DEBUGMARK instruction in the tail, so instruction is not a last
+            return false
+        }
+    }
+
+    return true
+}
+
 export const compileInstructions = (
     b: CodeBuilder,
     instructions: Instr[],
@@ -17,7 +48,7 @@ export const compileInstructions = (
         if (!instruction) break
         const builderBefore = new CodeBuilder().storeBuilder(b)
 
-        const isLast = index === instructions.length - 1
+        const isLast = isLastInstruction(index, instructions)
         const overflow = safeStore(b, instruction, isLast, options)
         if (!overflow) {
             // fast path
@@ -173,14 +204,20 @@ function compileIf(t: Instr, b: CodeBuilder, options: StoreOptions) {
         t.$ === "IFJMPREF" ||
         t.$ === "IFNOTJMPREF"
     ) {
-        const b2 = new CodeBuilder()
-        compilePushcont(b2, t.arg0, t.loc, options)
-        compileNonRefIf(b2, t, options)
+        try {
+            const b2 = new CodeBuilder()
 
-        if (b2.bits + b.bits <= 1023 && b2.refs + b.refs <= 4) {
-            compilePushcont(b, t.arg0, t.loc, options)
-            compileNonRefIf(b, t, options)
-            return true
+            // Try to compile, this code may throw an exception if PUSHCONT and IF doesn't fit into a single cell
+            compilePushcont(b2, t.arg0, t.loc, options)
+            compileNonRefIf(b2, t, options)
+
+            if (b2.bits + b.bits <= 1023 && b2.refs + b.refs <= 4) {
+                compilePushcont(b, t.arg0, t.loc, options)
+                compileNonRefIf(b, t, options)
+                return true
+            }
+        } catch {
+            return false
         }
     }
 

src/runtime/test/__snapshots__/compile.spec.ts.snap

@@ -0,0 +1,5 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Compile should compile Vault with skipRefs option enabled 1`] = `"606d59fd3f7551db56c690541e13026a47ed5df8c2c945177aeca543a8449027"`;
+
+exports[`Compile should compile Vault with skipRefs option enabled 2`] = `"606d59fd3f7551db56c690541e13026a47ed5df8c2c945177aeca543a8449027"`;

src/runtime/test/compile.spec.ts

@@ -0,0 +1,46 @@
+import {compileCellWithMapping, decompileCell} from "../instr"
+import {parse, print} from "../../text"
+import * as fs from "node:fs"
+import {diffLines} from "diff"
+
+const test = (text: string): (() => void) => {
+    return () => {
+        const res = parse("test.asm", text)
+        if (res.$ === "ParseFailure") {
+            return
+        }
+
+        const [compiled] = compileCellWithMapping(res.instructions, {skipRefs: true})
+        expect(compiled.hash().toString("hex")).toMatchSnapshot()
+
+        const withoutDebugMarks = text
+            .split(/\n/)
+            .filter(line => !line.includes("DEBUGMARK"))
+            .join("\n")
+
+        const res2 = parse("test.asm", withoutDebugMarks)
+        if (res2.$ === "ParseFailure") {
+            return
+        }
+
+        const [compiled2] = compileCellWithMapping(res2.instructions, {skipRefs: true})
+        expect(compiled2.hash().toString("hex")).toMatchSnapshot()
+
+        expect(compiled.hash().toString("hex")).toEqual(compiled2.hash().toString("hex"))
+
+        const compiledAssembly = print(decompileCell(compiled))
+        const compiledAssembly2 = print(decompileCell(compiled2))
+
+        if (compiledAssembly !== compiledAssembly2) {
+            console.log(diffLines(compiledAssembly, compiledAssembly2))
+            expect(true).toBe(false)
+        }
+    }
+}
+
+describe("Compile", () => {
+    it(
+        "should compile Vault with skipRefs option enabled",
+        test(fs.readFileSync(`${__dirname}/testdata/Vault.tasm`, "utf8")),
+    )
+})