Make sure main start function is compiled last

src/compiler.ts

@@ -452,35 +452,6 @@ export class Compiler extends DiagnosticEmitter {
       }
     }
 
-    // compile the start function if not empty or if explicitly requested
-    var startIsEmpty = !startFunctionBody.length;
-    var explicitStart = program.isWasi || options.explicitStart;
-    if (!startIsEmpty || explicitStart) {
-      let signature = startFunctionInstance.signature;
-      if (!startIsEmpty && explicitStart) {
-        module.addGlobal(BuiltinNames.started, NativeType.I32, true, module.i32(0));
-        startFunctionBody.unshift(
-          module.global_set(BuiltinNames.started, module.i32(1))
-        );
-        startFunctionBody.unshift(
-          module.if(
-            module.global_get(BuiltinNames.started, NativeType.I32),
-            module.return()
-          )
-        );
-      }
-      let funcRef = module.addFunction(
-        startFunctionInstance.internalName,
-        signature.nativeParams,
-        signature.nativeResults,
-        typesToNativeTypes(startFunctionInstance.additionalLocals),
-        module.flatten(startFunctionBody)
-      );
-      startFunctionInstance.finalize(module, funcRef);
-      if (!explicitStart) module.setStart(funcRef);
-      else module.addFunctionExport(startFunctionInstance.internalName, ExportNames.start);
-    }
-
     // check if the entire program is acyclic
     var cyclicClasses = program.findCyclicClasses();
     if (cyclicClasses.size) {
@@ -520,6 +491,37 @@ export class Compiler extends DiagnosticEmitter {
       compileClassInstanceOf(this, prototype);
     }
 
+    // NOTE: no more element compiles from here. may go to the start function!
+
+    // compile the start function if not empty or if explicitly requested
+    var startIsEmpty = !startFunctionBody.length;
+    var explicitStart = program.isWasi || options.explicitStart;
+    if (!startIsEmpty || explicitStart) {
+      let signature = startFunctionInstance.signature;
+      if (!startIsEmpty && explicitStart) {
+        module.addGlobal(BuiltinNames.started, NativeType.I32, true, module.i32(0));
+        startFunctionBody.unshift(
+          module.global_set(BuiltinNames.started, module.i32(1))
+        );
+        startFunctionBody.unshift(
+          module.if(
+            module.global_get(BuiltinNames.started, NativeType.I32),
+            module.return()
+          )
+        );
+      }
+      let funcRef = module.addFunction(
+        startFunctionInstance.internalName,
+        signature.nativeParams,
+        signature.nativeResults,
+        typesToNativeTypes(startFunctionInstance.additionalLocals),
+        module.flatten(startFunctionBody)
+      );
+      startFunctionInstance.finalize(module, funcRef);
+      if (!explicitStart) module.setStart(funcRef);
+      else module.addFunctionExport(startFunctionInstance.internalName, ExportNames.start);
+    }
+
     // set up virtual lookup tables
     var functionTable = this.functionTable;
     for (let i = 0, k = functionTable.length; i < k; ++i) {

tests/compiler/do.optimized.wat

@@ -1347,9 +1347,6 @@
    unreachable
   end
  )
- (func $~start
-  call $start:do
- )
  (func $~lib/rt/pure/decrement (param $0 i32)
   (local $1 i32)
   (local $2 i32)
@@ -1444,4 +1441,7 @@
    i32.store offset=4
   end
  )
+ (func $~start
+  call $start:do
+ )
 )

tests/compiler/do.untouched.wat

@@ -2231,9 +2231,6 @@
    unreachable
   end
  )
- (func $~start
-  call $start:do
- )
  (func $~lib/rt/tlsf/freeBlock (param $0 i32) (param $1 i32)
   local.get $1
   local.get $1
@@ -2340,6 +2337,9 @@
    i32.store offset=4
   end
  )
+ (func $~start
+  call $start:do
+ )
  (func $~lib/rt/pure/__visit (param $0 i32) (param $1 i32)
   local.get $0
   global.get $~lib/memory/__heap_base

tests/compiler/exports-lazy.optimized.wat

@@ -7,8 +7,8 @@
  (global $exports-lazy/lazyGlobalUsed i32 (i32.const 1088))
  (export "memory" (memory $0))
  (export "lazyGlobalUsed" (global $exports-lazy/lazyGlobalUsed))
- (export "lazyFuncUsed" (func $~start))
- (func $~start
+ (export "lazyFuncUsed" (func $exports-lazy/lazyFuncUsed))
+ (func $exports-lazy/lazyFuncUsed
   nop
  )
 )

tests/compiler/exports-lazy.untouched.wat

@@ -16,10 +16,10 @@
   drop
   call $exports-lazy/lazyFuncUsed
  )
- (func $~start
-  call $start:exports-lazy
- )
  (func $exports-lazy/lazyFuncUsed
   nop
  )
+ (func $~start
+  call $start:exports-lazy
+ )
 )

tests/compiler/extends-baseaggregate.optimized.wat

@@ -1718,9 +1718,6 @@
   local.get $0
   call $~lib/rt/pure/__release
  )
- (func $~start
-  call $start:extends-baseaggregate
- )
  (func $~lib/rt/pure/decrement (param $0 i32)
   (local $1 i32)
   (local $2 i32)
@@ -1886,6 +1883,9 @@
    end
   end
  )
+ (func $~start
+  call $start:extends-baseaggregate
+ )
  (func $~lib/rt/pure/scanBlack (param $0 i32)
   local.get $0
   local.get $0

tests/compiler/extends-baseaggregate.untouched.wat

@@ -3354,9 +3354,6 @@
   local.get $0
   call $~lib/rt/pure/__release
  )
- (func $~start
-  call $start:extends-baseaggregate
- )
  (func $~lib/rt/pure/finalize (param $0 i32)
   i32.const 0
   drop
@@ -3586,6 +3583,9 @@
    end
   end
  )
+ (func $~start
+  call $start:extends-baseaggregate
+ )
  (func $~lib/rt/pure/markGray (param $0 i32)
   (local $1 i32)
   local.get $0

tests/compiler/for.optimized.wat

@@ -1359,9 +1359,6 @@
    unreachable
   end
  )
- (func $~start
-  call $start:for
- )
  (func $~lib/rt/pure/decrement (param $0 i32)
   (local $1 i32)
   (local $2 i32)
@@ -1456,4 +1453,7 @@
    i32.store offset=4
   end
  )
+ (func $~start
+  call $start:for
+ )
 )

tests/compiler/for.untouched.wat

@@ -2276,9 +2276,6 @@
    unreachable
   end
  )
- (func $~start
-  call $start:for
- )
  (func $~lib/rt/tlsf/freeBlock (param $0 i32) (param $1 i32)
   local.get $1
   local.get $1
@@ -2385,6 +2382,9 @@
    i32.store offset=4
   end
  )
+ (func $~start
+  call $start:for
+ )
  (func $~lib/rt/pure/__visit (param $0 i32) (param $1 i32)
   local.get $0
   global.get $~lib/memory/__heap_base

tests/compiler/instanceof-class.optimized.wat

@@ -87,6 +87,36 @@
   i32.const 16
   i32.add
  )
+ (func $~lib/rt/__instanceof (param $0 i32) (param $1 i32) (result i32)
+  local.get $0
+  i32.const 20
+  i32.sub
+  i32.load offset=12
+  local.tee $0
+  i32.const 1104
+  i32.load
+  i32.le_u
+  if
+   loop $do-continue|0
+    local.get $0
+    local.get $1
+    i32.eq
+    if
+     i32.const 1
+     return
+    end
+    local.get $0
+    i32.const 3
+    i32.shl
+    i32.const 1108
+    i32.add
+    i32.load offset=4
+    local.tee $0
+    br_if $do-continue|0
+   end
+  end
+  i32.const 0
+ )
  (func $~start
   (local $0 i32)
   i32.const 1164
@@ -140,34 +170,4 @@
    unreachable
   end
  )
- (func $~lib/rt/__instanceof (param $0 i32) (param $1 i32) (result i32)
-  local.get $0
-  i32.const 20
-  i32.sub
-  i32.load offset=12
-  local.tee $0
-  i32.const 1104
-  i32.load
-  i32.le_u
-  if
-   loop $do-continue|0
-    local.get $0
-    local.get $1
-    i32.eq
-    if
-     i32.const 1
-     return
-    end
-    local.get $0
-    i32.const 3
-    i32.shl
-    i32.const 1108
-    i32.add
-    i32.load offset=4
-    local.tee $0
-    br_if $do-continue|0
-   end
-  end
-  i32.const 0
- )
 )

tests/compiler/instanceof-class.untouched.wat

@@ -254,9 +254,6 @@
   i32.eqz
   drop
  )
- (func $~start
-  call $start:instanceof-class
- )
  (func $~lib/rt/__instanceof (param $0 i32) (param $1 i32) (result i32)
   (local $2 i32)
   (local $3 i32)
@@ -321,4 +318,7 @@
   i32.const 0
   return
  )
+ (func $~start
+  call $start:instanceof-class
+ )
 )