Remove the start decorator in favor of a command line option

cli/asc.js

@@ -441,6 +441,7 @@ exports.main = function main(argv, options, callback) {
   assemblyscript.setImportMemory(compilerOptions, args.importMemory);
   assemblyscript.setSharedMemory(compilerOptions, args.sharedMemory);
   assemblyscript.setImportTable(compilerOptions, args.importTable);
+  assemblyscript.setExplicitStart(compilerOptions, args.explicitStart);
   assemblyscript.setMemoryBase(compilerOptions, args.memoryBase >>> 0);
   assemblyscript.setSourceMap(compilerOptions, args.sourceMap != null);
   assemblyscript.setOptimizeLevelHints(compilerOptions, optimizeLevel, shrinkLevel);

cli/asc.json

@@ -129,6 +129,11 @@
     "type": "b",
     "default": false
   },
+  "explicitStart": {
+    "description": "Exports an explicit start function to be called manually.",
+    "type": "b",
+    "default": false
+  },
   "lib": {
     "description": [
       "Adds one or multiple paths to custom library components and",

lib/loader/README.md

@@ -100,6 +100,9 @@ Besides demangling classes exported from your entry file to a handy object struc
   var value = module.F64[ptr >>> 3];
   ```
 
+* **__start**(): `void`<br />
+  Explicit start function if the `--explicit-start` option is used. Must be called before any other exports if present.
+
 * **__allocString**(str: `string`): `number`<br />
   Allocates a new string in the module's memory and returns a reference (pointer) to it.
 

lib/loader/index.d.ts

@@ -43,6 +43,8 @@ interface ASUtil {
   readonly F32: Float32Array;
   /** A 64-bit float view on the memory. */
   readonly F64: Float64Array;
+  /** Explicit start function, if requested. */
+  __start(): void;
   /** Allocates a new string in the module's memory and returns a reference (pointer) to it. */
   __allocString(str: string): number;
   /** Reads (copies) the value of a string from the module's memory. */

src/ast.ts

@@ -1184,7 +1184,6 @@ export enum DecoratorKind {
   EXTERNAL,
   BUILTIN,
   LAZY,
-  START,
   UNSAFE
 }
 
@@ -1221,7 +1220,6 @@ export function decoratorNameToKind(name: Expression): DecoratorKind {
       }
       case CharCode.s: {
         if (nameStr == "sealed") return DecoratorKind.SEALED;
-        if (nameStr == "start") return DecoratorKind.START;
         break;
       }
       case CharCode.u: {

src/compiler.ts

@@ -193,6 +193,8 @@ export class Options {
   importTable: bool = false;
   /** If true, generates information necessary for source maps. */
   sourceMap: bool = false;
+  /** If true, generates an explicit start function. */
+  explicitStart: bool = false;
   /** Static memory start offset. */
   memoryBase: i32 = 0;
   /** Global aliases. */
@@ -366,10 +368,21 @@ export class Compiler extends DiagnosticEmitter {
       }
     }
 
-    // compile the start function if not empty or called by main
-    var hasExplicitStart = program.explicitStartFunction !== null;
-    if (startFunctionBody.length || hasExplicitStart) {
+    // compile the start function if not empty or explicitly requested
+    var startIsEmpty = !startFunctionBody.length;
+    var explicitStart = options.explicitStart;
+    if (!startIsEmpty || explicitStart) {
       let signature = startFunctionInstance.signature;
+      if (!startIsEmpty && explicitStart) {
+        module.addGlobal(BuiltinSymbols.started, NativeType.I32, true, module.i32(0));
+        startFunctionBody.unshift(
+          module.if(
+            module.global_get(BuiltinSymbols.started, NativeType.I32),
+            module.return(),
+            module.global_set(BuiltinSymbols.started, module.i32(1))
+          )
+        );
+      }
       let funcRef = module.addFunction(
         startFunctionInstance.internalName,
         this.ensureFunctionType(
@@ -381,7 +394,8 @@ export class Compiler extends DiagnosticEmitter {
         module.block(null, startFunctionBody)
       );
       startFunctionInstance.finalize(module, funcRef);
-      if (!hasExplicitStart) module.setStart(funcRef);
+      if (!explicitStart) module.setStart(funcRef);
+      else module.addFunctionExport(startFunctionInstance.internalName, "__start");
     }
 
     // compile runtime features
@@ -1149,23 +1163,6 @@ export class Compiler extends DiagnosticEmitter {
       }
     }
 
-    // make the main function call `start` implicitly, but only once
-    if (instance.prototype == this.program.explicitStartFunction) {
-      module.addGlobal(BuiltinSymbols.started, NativeType.I32, true, module.i32(0));
-      stmts.unshift(
-        module.if(
-          module.unary(
-            UnaryOp.EqzI32,
-            module.global_get(BuiltinSymbols.started, NativeType.I32)
-          ),
-          module.block(null, [
-            module.call("start", null, NativeType.None),
-            module.global_set(BuiltinSymbols.started, module.i32(1))
-          ])
-        )
-      );
-    }
-
     // make constructors return their instance pointer
     if (instance.is(CommonFlags.CONSTRUCTOR)) {
       let nativeSizeType = this.options.nativeSizeType;

src/index.ts

@@ -99,6 +99,11 @@ export function setGlobalAlias(options: Options, name: string, alias: string): v
   globalAliases.set(name, alias);
 }
 
+/** Sets the `explicitStart` option. */
+export function setExplicitStart(options: Options, explicitStart: bool): void {
+  options.explicitStart = explicitStart;
+}
+
 /** Sign extension operations. */
 export const FEATURE_SIGN_EXTENSION = Feature.SIGN_EXTENSION;
 /** Mutable global imports and exports. */

src/program.ts

@@ -321,8 +321,6 @@ export class Program extends DiagnosticEmitter {
   nativeSource: Source;
   /** Special native code file. */
   nativeFile: File;
-  /** Explicitly annotated start function. */
-  explicitStartFunction: FunctionPrototype | null = null;
 
   // lookup maps
 
@@ -1663,11 +1661,6 @@ export class Program extends DiagnosticEmitter {
         validDecorators |= DecoratorFlags.GLOBAL;
       }
     }
-    if (!declaration.is(CommonFlags.GENERIC)) {
-      if (parent.kind == ElementKind.FILE && (<File>parent).source.isEntry) {
-        validDecorators |= DecoratorFlags.START;
-      }
-    }
     var element = new FunctionPrototype(
       name,
       parent,
@@ -1675,14 +1668,6 @@ export class Program extends DiagnosticEmitter {
       this.checkDecorators(declaration.decorators, validDecorators)
     );
     if (!parent.add(name, element)) return null;
-    if (element.hasDecorator(DecoratorFlags.START)) {
-      if (this.explicitStartFunction) {
-        this.error(
-          DiagnosticCode.Module_cannot_have_multiple_start_functions,
-          assert(findDecorator(DecoratorKind.START, declaration.decorators)).range
-        );
-      } else this.explicitStartFunction = element;
-    }
     return element;
   }
 
@@ -1921,10 +1906,8 @@ export enum DecoratorFlags {
   BUILTIN = 1 << 8,
   /** Is compiled lazily. */
   LAZY = 1 << 9,
-  /** Is the explicit start function. */
-  START = 1 << 10,
   /** Is considered unsafe code. */
-  UNSAFE = 1 << 11
+  UNSAFE = 1 << 10
 }
 
 /** Translates a decorator kind to the respective decorator flag. */
@@ -1941,7 +1924,6 @@ export function decoratorKindToFlag(kind: DecoratorKind): DecoratorFlags {
     case DecoratorKind.EXTERNAL: return DecoratorFlags.EXTERNAL;
     case DecoratorKind.BUILTIN: return DecoratorFlags.BUILTIN;
     case DecoratorKind.LAZY: return DecoratorFlags.LAZY;
-    case DecoratorKind.START: return DecoratorFlags.START;
     case DecoratorKind.UNSAFE: return DecoratorFlags.UNSAFE;
     default: return DecoratorFlags.NONE;
   }

tests/compiler.js

@@ -351,10 +351,9 @@ function testInstantiate(basename, binaryBuffer, name) {
           "var": 3
         }
       }).exports;
-      if (exports.main) {
-        console.log(colorsUtil.white("  [main]"));
-        let code = exports.main();
-        console.log(colorsUtil.white("  [exit " + code + "]\n"));
+      if (exports.__start) {
+        console.log(colorsUtil.white("  [start]"));
+        exports.__start();
       }
     });
     let leakCount = rtr.check();

tests/compiler/main.json

@@ -1,5 +0,0 @@
-{
-  "asc_flags": [
-    "--runtime none"
-  ]
-}

tests/compiler/main.optimized.wat

@@ -1,23 +0,0 @@
-(module
- (type $FUNCSIG$v (func))
- (type $FUNCSIG$iii (func (param i32 i32) (result i32)))
- (memory $0 0)
- (global $main/code (mut i32) (i32.const 0))
- (global $~lib/started (mut i32) (i32.const 0))
- (export "memory" (memory $0))
- (export "main" (func $main/main))
- (func $main/main (; 0 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
-  global.get $~lib/started
-  i32.eqz
-  if
-   i32.const 1
-   global.set $main/code
-   i32.const 1
-   global.set $~lib/started
-  end
-  global.get $main/code
- )
- (func $null (; 1 ;) (type $FUNCSIG$v)
-  nop
- )
-)

tests/compiler/main.ts

@@ -1,7 +0,0 @@
-var code = 0;
-code = 1;
-
-@start
-export function main(argc: i32, argv: usize): i32 {
-  return code;
-}

tests/compiler/main.untouched.wat

@@ -1,30 +0,0 @@
-(module
- (type $FUNCSIG$v (func))
- (type $FUNCSIG$iii (func (param i32 i32) (result i32)))
- (memory $0 0)
- (table $0 1 funcref)
- (elem (i32.const 0) $null)
- (global $main/code (mut i32) (i32.const 0))
- (global $~lib/started (mut i32) (i32.const 0))
- (export "memory" (memory $0))
- (export "main" (func $main/main))
- (func $start:main (; 0 ;) (type $FUNCSIG$v)
-  i32.const 1
-  global.set $main/code
- )
- (func $main/main (; 1 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
-  global.get $~lib/started
-  i32.eqz
-  if
-   call $start
-   i32.const 1
-   global.set $~lib/started
-  end
-  global.get $main/code
- )
- (func $start (; 2 ;) (type $FUNCSIG$v)
-  call $start:main
- )
- (func $null (; 3 ;) (type $FUNCSIG$v)
- )
-)

tests/compiler/retain-release-sanity.optimized.wat

@@ -33,9 +33,8 @@
  (global $~lib/rt/pure/CUR (mut i32) (i32.const 0))
  (global $~lib/rt/pure/END (mut i32) (i32.const 0))
  (global $~lib/rt/pure/ROOTS (mut i32) (i32.const 0))
- (global $~lib/started (mut i32) (i32.const 0))
  (export "memory" (memory $0))
- (export "main" (func $retain-release-sanity/main))
+ (start $start)
  (func $~lib/rt/tlsf/removeBlock (; 5 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
@@ -2601,14 +2600,8 @@
   call $~lib/rt/pure/__release
   call $~lib/rt/pure/__collect
  )
- (func $retain-release-sanity/main (; 42 ;) (type $FUNCSIG$v)
-  global.get $~lib/started
-  i32.eqz
-  if
-   call $start:retain-release-sanity
-   i32.const 1
-   global.set $~lib/started
-  end
+ (func $start (; 42 ;) (type $FUNCSIG$v)
+  call $start:retain-release-sanity
  )
  (func $~lib/rt/pure/__visit (; 43 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   local.get $0

tests/compiler/retain-release-sanity.ts

@@ -1,4 +1,3 @@
-@start export function main(): void {}
 {
   let arr: i32[] = new Array<i32>(3);
   arr.push(123);

tests/compiler/retain-release-sanity.untouched.wat

@@ -36,11 +36,10 @@
  (global $~lib/rt/pure/END (mut i32) (i32.const 0))
  (global $~lib/rt/pure/ROOTS (mut i32) (i32.const 0))
  (global $~lib/ASC_SHRINK_LEVEL i32 (i32.const 0))
- (global $~lib/started (mut i32) (i32.const 0))
  (global $~lib/rt/__rtti_base i32 (i32.const 680))
  (global $~lib/heap/__heap_base i32 (i32.const 748))
  (export "memory" (memory $0))
- (export "main" (func $retain-release-sanity/main))
+ (start $start)
  (func $~lib/rt/tlsf/removeBlock (; 5 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
@@ -4537,22 +4536,13 @@
   end
   call $~lib/rt/pure/__collect
  )
- (func $retain-release-sanity/main (; 48 ;) (type $FUNCSIG$v)
-  global.get $~lib/started
-  i32.eqz
-  if
-   call $start
-   i32.const 1
-   global.set $~lib/started
-  end
- )
- (func $start (; 49 ;) (type $FUNCSIG$v)
+ (func $start (; 48 ;) (type $FUNCSIG$v)
   call $start:retain-release-sanity
  )
- (func $~lib/array/Array<i32>#__visit_impl (; 50 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<i32>#__visit_impl (; 49 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/rt/pure/__visit (; 51 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/pure/__visit (; 50 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   local.get $0
@@ -4706,7 +4696,7 @@
    end
   end
  )
- (func $~lib/array/Array<~lib/string/String>#__visit_impl (; 52 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<~lib/string/String>#__visit_impl (; 51 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   (local $4 i32)
@@ -4744,7 +4734,7 @@
    end
   end
  )
- (func $~lib/array/Array<~lib/array/Array<~lib/string/String>>#__visit_impl (; 53 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<~lib/array/Array<~lib/string/String>>#__visit_impl (; 52 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   (local $4 i32)
@@ -4782,7 +4772,7 @@
    end
   end
  )
- (func $~lib/rt/__visit_members (; 54 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/__visit_members (; 53 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   block $block$4$break
    block
@@ -4896,6 +4886,6 @@
   end
   unreachable
  )
- (func $null (; 55 ;) (type $FUNCSIG$v)
+ (func $null (; 54 ;) (type $FUNCSIG$v)
  )
 )

tests/compiler/retain-release.json

@@ -1,5 +1,6 @@
 {
   "asc_flags": [
-    "--runtime none"
+    "--runtime none",
+    "--explicitStart"
   ]
 }

tests/compiler/retain-release.optimized.wat

@@ -17,6 +17,8 @@
  (global $retain-release/glo (mut i32) (i32.const 0))
  (global $retain-release/TARGET (mut i32) (i32.const 0))
  (global $~lib/argc (mut i32) (i32.const 0))
+ (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
  (export "returnRef" (func $retain-release/returnRef))
  (export "receiveRef" (func $retain-release/receiveRef))
@@ -52,7 +54,6 @@
  (export "provideRefIndirect" (func $retain-release/provideRefIndirect))
  (export "receiveRefIndirect" (func $retain-release/receiveRefIndirect))
  (export "receiveRefIndirectDrop" (func $retain-release/receiveRefIndirect))
- (start $start)
  (func $~lib/rt/stub/__alloc (; 1 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
   (local $2 i32)
   (local $3 i32)
@@ -206,6 +207,13 @@
  )
  (func $start (; 15 ;) (type $FUNCSIG$v)
   (local $0 i32)
+  global.get $~lib/started
+  if
+   return
+  else   
+   i32.const 1
+   global.set $~lib/started
+  end
   i32.const 96
   global.set $~lib/rt/stub/startOffset
   global.get $~lib/rt/stub/startOffset

tests/compiler/retain-release.untouched.wat

@@ -17,7 +17,9 @@
  (global $retain-release/glo (mut i32) (i32.const 0))
  (global $retain-release/TARGET (mut i32) (i32.const 0))
  (global $~lib/argc (mut i32) (i32.const 0))
+ (global $~lib/started (mut i32) (i32.const 0))
  (global $~lib/heap/__heap_base i32 (i32.const 92))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
  (export "returnRef" (func $retain-release/returnRef))
  (export "receiveRef" (func $retain-release/receiveRef))
@@ -53,7 +55,6 @@
  (export "provideRefIndirect" (func $retain-release/provideRefIndirect))
  (export "receiveRefIndirect" (func $retain-release/receiveRefIndirect))
  (export "receiveRefIndirectDrop" (func $retain-release/receiveRefIndirectDrop))
- (start $start)
  (func $~lib/rt/stub/__alloc (; 1 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
   (local $2 i32)
   (local $3 i32)
@@ -666,6 +667,13 @@
   call $~lib/rt/stub/__release
  )
  (func $start (; 41 ;) (type $FUNCSIG$v)
+  global.get $~lib/started
+  if
+   return
+  else   
+   i32.const 1
+   global.set $~lib/started
+  end
   call $start:retain-release
  )
  (func $null (; 42 ;) (type $FUNCSIG$v)

tests/compiler/rt/instanceof.json

@@ -1,5 +1,6 @@
 {
   "asc_flags": [
-    "--runtime none"
+    "--runtime none",
+    "--explicitStart"
   ]
 }

tests/compiler/rt/instanceof.optimized.wat

@@ -20,8 +20,8 @@
  (global $rt/instanceof/nullCat i32 (i32.const 0))
  (global $rt/instanceof/nullBlackcat i32 (i32.const 0))
  (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $rt/instanceof/main))
  (func $~lib/rt/stub/__alloc (; 1 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   (local $1 i32)
   (local $2 i32)
@@ -531,14 +531,15 @@
    unreachable
   end
  )
- (func $rt/instanceof/main (; 7 ;) (type $FUNCSIG$v)
+ (func $start (; 7 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start:rt/instanceof
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
+  call $start:rt/instanceof
  )
  (func $null (; 8 ;) (type $FUNCSIG$v)
   nop

tests/compiler/rt/instanceof.ts

@@ -49,5 +49,3 @@ assert(!(nullCat instanceof BlackCat)); // dynamic false
 assert(!(nullBlackcat instanceof Animal)); // static false
 assert(!(nullBlackcat instanceof Cat)); // dynamic false
 assert(!(nullBlackcat instanceof BlackCat)); // dynamic false
-
-@start export function main(): void {}

tests/compiler/rt/instanceof.untouched.wat

@@ -24,8 +24,8 @@
  (global $~lib/started (mut i32) (i32.const 0))
  (global $~lib/rt/__rtti_base i32 (i32.const 56))
  (global $~lib/heap/__heap_base i32 (i32.const 108))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $rt/instanceof/main))
  (func $~lib/rt/stub/__alloc (; 1 ;) (type $FUNCSIG$iii) (param $0 i32) (param $1 i32) (result i32)
   (local $2 i32)
   (local $3 i32)
@@ -719,18 +719,16 @@
    unreachable
   end
  )
- (func $rt/instanceof/main (; 9 ;) (type $FUNCSIG$v)
+ (func $start (; 9 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
- )
- (func $start (; 10 ;) (type $FUNCSIG$v)
   call $start:rt/instanceof
  )
- (func $null (; 11 ;) (type $FUNCSIG$v)
+ (func $null (; 10 ;) (type $FUNCSIG$v)
  )
 )

tests/compiler/std/array.json

@@ -1,6 +1,7 @@
 {
   "asc_flags": [
-    "--runtime full",
+    "--runtime half",
+    "--explicitStart",
     "--use ASC_RTRACE=1"
   ]
 }

tests/compiler/std/array.ts

@@ -1,8 +1,6 @@
 import { Array } from "array";
 import { COMPARATOR } from "util/sort";
 
-@start export function main(): void {}
-
 // Obtains the internal capacity of an array from its backing buffer.
 function internalCapacity<T>(array: Array<T>): i32 {
   // the memory region used by the backing buffer might still be larger in that the ArrayBuffer

tests/compiler/std/string.json

@@ -1,6 +1,7 @@
 {
   "asc_flags": [
     "--runtime half",
+    "--explicitStart",
     "--use ASC_RTRACE=1"
   ]
 }

tests/compiler/std/string.optimized.wat

@@ -193,9 +193,9 @@
  (global $~lib/util/number/_frc_pow (mut i64) (i64.const 0))
  (global $~lib/util/number/_exp_pow (mut i32) (i32.const 0))
  (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
  (export "getString" (func $std/string/getString))
- (export "main" (func $std/string/main))
  (func $~lib/string/String#get:length (; 5 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   local.get $0
   i32.const 16
@@ -8925,14 +8925,15 @@
   global.get $std/string/str
   call $~lib/rt/pure/__retain
  )
- (func $std/string/main (; 75 ;) (type $FUNCSIG$v)
+ (func $start (; 75 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start:std/string
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
+  call $start:std/string
  )
  (func $~lib/rt/pure/markGray (; 76 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)

tests/compiler/std/string.ts

@@ -310,5 +310,3 @@ export function getString(): string {
 // Unleak globals
 
 __release(changetype<usize>(str));
-
-@start export function main(): void {}

tests/compiler/std/string.untouched.wat

@@ -211,9 +211,9 @@
  (global $~lib/started (mut i32) (i32.const 0))
  (global $~lib/rt/__rtti_base i32 (i32.const 7032))
  (global $~lib/heap/__heap_base i32 (i32.const 7100))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
  (export "getString" (func $std/string/getString))
- (export "main" (func $std/string/main))
  (func $~lib/string/String#get:length (; 5 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
   local.get $0
   i32.const 16
@@ -12141,19 +12141,17 @@
   global.get $std/string/str
   call $~lib/rt/pure/__retain
  )
- (func $std/string/main (; 84 ;) (type $FUNCSIG$v)
+ (func $start (; 84 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
- )
- (func $start (; 85 ;) (type $FUNCSIG$v)
   call $start:std/string
  )
- (func $~lib/rt/pure/markGray (; 86 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/markGray (; 85 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -12180,7 +12178,7 @@
    call $~lib/rt/__visit_members
   end
  )
- (func $~lib/rt/pure/scanBlack (; 87 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/scanBlack (; 86 ;) (type $FUNCSIG$vi) (param $0 i32)
   local.get $0
   local.get $0
   i32.load offset=4
@@ -12197,7 +12195,7 @@
   i32.const 4
   call $~lib/rt/__visit_members
  )
- (func $~lib/rt/pure/scan (; 88 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/scan (; 87 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -12234,7 +12232,7 @@
    end
   end
  )
- (func $~lib/rt/pure/collectWhite (; 89 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/collectWhite (; 88 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -12272,7 +12270,7 @@
    call $~lib/rt/tlsf/freeBlock
   end
  )
- (func $~lib/rt/pure/__visit (; 90 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/pure/__visit (; 89 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   local.get $0
@@ -12426,7 +12424,7 @@
    end
   end
  )
- (func $~lib/array/Array<~lib/string/String>#__visit_impl (; 91 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<~lib/string/String>#__visit_impl (; 90 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   (local $4 i32)
@@ -12464,19 +12462,19 @@
    end
   end
  )
- (func $~lib/array/Array<i32>#__visit_impl (; 92 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<i32>#__visit_impl (; 91 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/array/Array<u32>#__visit_impl (; 93 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<u32>#__visit_impl (; 92 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/array/Array<u64>#__visit_impl (; 94 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<u64>#__visit_impl (; 93 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/array/Array<i16>#__visit_impl (; 95 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<i16>#__visit_impl (; 94 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/rt/__visit_members (; 96 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/__visit_members (; 95 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   block $block$4$break
    block
@@ -12626,6 +12624,6 @@
   end
   unreachable
  )
- (func $null (; 97 ;) (type $FUNCSIG$v)
+ (func $null (; 96 ;) (type $FUNCSIG$v)
  )
 )

tests/compiler/std/trace.json

@@ -1,5 +1,6 @@
 {
   "asc_flags": [
-    "--runtime none"
+    "--runtime none",
+    "--explicitStart"
   ]
 }

tests/compiler/std/trace.optimized.wat

@@ -12,8 +12,8 @@
  (data (i32.const 240) "\10\00\00\00\01\00\00\00\01\00\00\00\10\00\00\00f\00i\00v\00e\00_\00i\00n\00t")
  (data (i32.const 272) "\10\00\00\00\01\00\00\00\01\00\00\00\10\00\00\00f\00i\00v\00e\00_\00d\00b\00l")
  (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $std/trace/main))
  (func $start:std/trace (; 1 ;) (type $FUNCSIG$v)
   i32.const 24
   i32.const 0
@@ -80,14 +80,15 @@
   f64.const 5.5
   call $~lib/builtins/trace
  )
- (func $std/trace/main (; 2 ;) (type $FUNCSIG$v)
+ (func $start (; 2 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start:std/trace
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
+  call $start:std/trace
  )
  (func $null (; 3 ;) (type $FUNCSIG$v)
   nop

tests/compiler/std/trace.ts

@@ -6,6 +6,3 @@ trace("three_int", 3, 1, 2, 3);
 trace("four_int", 4, 1, 2, 3, 4);
 trace("five_int", 5, 1, 2, 3, 4, 5);
 trace("five_dbl", 5, 1.1, 2.2, 3.3, 4.4, 5.5);
-
-@start
-export function main(): void {}

tests/compiler/std/trace.untouched.wat

@@ -14,8 +14,8 @@
  (table $0 1 funcref)
  (elem (i32.const 0) $null)
  (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $std/trace/main))
  (func $start:std/trace (; 1 ;) (type $FUNCSIG$v)
   i32.const 24
   i32.const 0
@@ -82,18 +82,16 @@
   f64.const 5.5
   call $~lib/builtins/trace
  )
- (func $std/trace/main (; 2 ;) (type $FUNCSIG$v)
+ (func $start (; 2 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
- )
- (func $start (; 3 ;) (type $FUNCSIG$v)
   call $start:std/trace
  )
- (func $null (; 4 ;) (type $FUNCSIG$v)
+ (func $null (; 3 ;) (type $FUNCSIG$v)
  )
 )

tests/compiler/std/typedarray.json

@@ -1,6 +1,7 @@
 {
   "asc_flags": [
     "--runtime half",
+    "--explicitStart",
     "--use ASC_RTRACE=1"
   ]
 }

tests/compiler/std/typedarray.optimized.wat

@@ -87,8 +87,8 @@
  (global $std/typedarray/forEachValues i32 (i32.const 1112))
  (global $std/typedarray/testArrayReverseValues i32 (i32.const 1480))
  (global $~lib/started (mut i32) (i32.const 0))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $std/typedarray/main))
  (func $~lib/rt/tlsf/removeBlock (; 5 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
@@ -15524,14 +15524,15 @@
   global.get $std/typedarray/testArrayReverseValues
   call $~lib/rt/pure/__release
  )
- (func $std/typedarray/main (; 285 ;) (type $FUNCSIG$v)
+ (func $start (; 285 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start:std/typedarray
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
+  call $start:std/typedarray
  )
  (func $~lib/rt/pure/markGray (; 286 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)

tests/compiler/std/typedarray.ts

@@ -491,8 +491,6 @@ testArrayReverse<Uint64Array, u64>();
 testArrayReverse<Float32Array, f32>();
 testArrayReverse<Float64Array, f64>();
 
-@start export function main(): void {}
-
 // Unleak globals
 
 __release(changetype<usize>(forEachValues));

tests/compiler/std/typedarray.untouched.wat

@@ -104,8 +104,8 @@
  (global $~lib/started (mut i32) (i32.const 0))
  (global $~lib/rt/__rtti_base i32 (i32.const 1688))
  (global $~lib/heap/__heap_base i32 (i32.const 1820))
+ (export "__start" (func $start))
  (export "memory" (memory $0))
- (export "main" (func $std/typedarray/main))
  (func $~lib/rt/tlsf/removeBlock (; 5 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
@@ -23151,25 +23151,23 @@
   global.get $std/typedarray/testArrayReverseValues
   call $~lib/rt/pure/__release
  )
- (func $std/typedarray/main (; 393 ;) (type $FUNCSIG$v)
+ (func $start (; 393 ;) (type $FUNCSIG$v)
   global.get $~lib/started
-  i32.eqz
   if
-   call $start
+   return
+  else   
    i32.const 1
    global.set $~lib/started
   end
- )
- (func $start (; 394 ;) (type $FUNCSIG$v)
   call $start:std/typedarray
  )
- (func $~lib/array/Array<i8>#__visit_impl (; 395 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<i8>#__visit_impl (; 394 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/array/Array<i32>#__visit_impl (; 396 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/array/Array<i32>#__visit_impl (; 395 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   nop
  )
- (func $~lib/rt/pure/markGray (; 397 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/markGray (; 396 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -23196,7 +23194,7 @@
    call $~lib/rt/__visit_members
   end
  )
- (func $~lib/rt/pure/scanBlack (; 398 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/scanBlack (; 397 ;) (type $FUNCSIG$vi) (param $0 i32)
   local.get $0
   local.get $0
   i32.load offset=4
@@ -23213,7 +23211,7 @@
   i32.const 4
   call $~lib/rt/__visit_members
  )
- (func $~lib/rt/pure/scan (; 399 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/scan (; 398 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -23250,7 +23248,7 @@
    end
   end
  )
- (func $~lib/rt/pure/collectWhite (; 400 ;) (type $FUNCSIG$vi) (param $0 i32)
+ (func $~lib/rt/pure/collectWhite (; 399 ;) (type $FUNCSIG$vi) (param $0 i32)
   (local $1 i32)
   local.get $0
   i32.load offset=4
@@ -23288,7 +23286,7 @@
    call $~lib/rt/tlsf/freeBlock
   end
  )
- (func $~lib/rt/pure/__visit (; 401 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/pure/__visit (; 400 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   (local $3 i32)
   local.get $0
@@ -23442,7 +23440,7 @@
    end
   end
  )
- (func $~lib/rt/__visit_members (; 402 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
+ (func $~lib/rt/__visit_members (; 401 ;) (type $FUNCSIG$vii) (param $0 i32) (param $1 i32)
   (local $2 i32)
   block $block$4$break
    block
@@ -23538,6 +23536,6 @@
   end
   unreachable
  )
- (func $null (; 403 ;) (type $FUNCSIG$v)
+ (func $null (; 402 ;) (type $FUNCSIG$v)
  )
 )

tests/runtime/assembly/index.ts

@@ -1 +1 @@
-@start export function main(): void {}
+export { __free };

tests/runtime/index.html

@@ -27,6 +27,7 @@ fetch("untouched.wasm").then(result =>
   })
 ).then(result => {
   exports = result.instance.exports;
+  if (exports.__start) exports.__start();
   U32 = new Uint32Array(exports.memory.buffer);
   var first = exports.__alloc(255);
   exports.__free(first);