import memory #684

Author: kripken

src/asm2wasm.h

@@ -817,11 +817,22 @@ void Asm2WasmBuilder::processAsm(Ref ast) {
     wasm.addExport(export_);
   }
 
+#if 0
+  // export memory
   auto memoryExport = make_unique<Export>();
   memoryExport->name = MEMORY;
   memoryExport->value = Name::fromInt(0);
   memoryExport->kind = Export::Memory;
   wasm.addExport(memoryExport.release());
+#else
+  // import memory
+  auto memoryImport = make_unique<Import>();
+  memoryImport->name = MEMORY;
+  memoryImport->module = ENV;
+  memoryImport->base = MEMORY;
+  memoryImport->kind = Import::Memory;
+  wasm.addImport(memoryImport.release());
+#endif
 
 #if 0 // enable asm2wasm i64 optimizations when browsers have consistent i64 support in wasm
   if (udivmoddi4.is() && getTempRet0.is()) {

src/js/wasm.js-post.js

@@ -183,7 +183,7 @@ function integrateWasmJS(Module) {
       return false;
     }
     exports = instance.exports;
-    mergeMemory(exports.memory);
+    if (exports.memory) mergeMemory(exports.memory);
 
     Module["usingWasm"] = true;
 
@@ -274,6 +274,11 @@ function integrateWasmJS(Module) {
     global = fixImports(global);
     env = fixImports(env);
 
+    // import memory
+    if (!env['memory']) {
+      env['memory'] = providedBuffer;
+    }
+    
     // try the methods. each should return the exports if it succeeded
 
     var exports;

src/wasm-js.cpp

@@ -169,17 +169,36 @@ extern "C" void EMSCRIPTEN_KEEPALIVE instantiate() {
 
   struct JSExternalInterface : ModuleInstance::ExternalInterface {
     void init(Module& wasm, ModuleInstance& instance) override {
-      // create a new buffer here, just like native wasm support would.
-      EM_ASM_({
-        Module['outside']['newBuffer'] = new ArrayBuffer($0);
-      }, wasm.memory.initial * Memory::kPageSize);
+      // look for imported memory
+      {
+        bool found = false;
+        for (auto& import : wasm.imports) {
+          if (import->module == ENV && import->base == MEMORY) {
+            assert(import->kind == Import::Memory);
+            // memory is imported
+            EM_ASM({
+              Module['outside']['tempBuffer'] = Module['lookupImport']('env', 'memory');
+            });
+            found = true;
+          }
+        }
+        if (!found) {
+          // no memory import; create a new buffer here, just like native wasm support would.
+          EM_ASM_({
+            Module['outside']['tempBuffer'] = Module['outside']['newBuffer'] = new ArrayBuffer($0);
+          }, wasm.memory.initial * Memory::kPageSize);
+        }
+      }
       for (auto segment : wasm.memory.segments) {
         EM_ASM_({
           var source = Module['HEAP8'].subarray($1, $1 + $2);
-          var target = new Int8Array(Module['outside']['newBuffer']);
+          var target = new Int8Array(Module['outside']['tempBuffer']);
           target.set(source, $0);
         }, ConstantExpressionRunner(instance.globals).visit(segment.offset).value.geti32(), &segment.data[0], segment.data.size());
       }
+      EM_ASM({
+        Module['outside']['tempBuffer'] = null;
+      });
       // Table support is in a JS array. If the entry is a number, it's a function pointer. If not, it's a JS method to be called directly
       // TODO: make them all JS methods, wrapping a dynCall where necessary?
       EM_ASM_({

test/emcc_O2_hello_world.fromasm

@@ -30,6 +30,7 @@
   (import $___syscall140 "env" "___syscall140" (param i32 i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "_free" $_free)
   (export "_main" $_main)
@@ -49,7 +50,6 @@
   (export "dynCall_ii" $dynCall_ii)
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_O2_hello_world.fromasm.imprecise

@@ -28,6 +28,7 @@
   (import $___unlock "env" "___unlock" (param i32))
   (import $___syscall140 "env" "___syscall140" (param i32 i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $_free)
   (export "_main" $_main)
   (export "_memset" $_memset)
@@ -46,7 +47,6 @@
   (export "dynCall_ii" $dynCall_ii)
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_O2_hello_world.fromasm.imprecise.no-opts

@@ -28,6 +28,7 @@
   (import $___unlock "env" "___unlock" (param i32))
   (import $___syscall140 "env" "___syscall140" (param i32 i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $_free)
   (export "_main" $_main)
   (export "_memset" $_memset)
@@ -46,7 +47,6 @@
   (export "dynCall_ii" $dynCall_ii)
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_O2_hello_world.fromasm.no-opts

@@ -29,6 +29,7 @@
   (import $___syscall140 "env" "___syscall140" (param i32 i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $_free)
   (export "_main" $_main)
   (export "_memset" $_memset)
@@ -47,7 +48,6 @@
   (export "dynCall_ii" $dynCall_ii)
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_hello_world.fromasm

@@ -39,6 +39,7 @@
   (import $i32s-rem "asm2wasm" "i32s-rem" (param i32 i32) (result i32))
   (import $i32u-rem "asm2wasm" "i32u-rem" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "_i64Subtract" $_i64Subtract)
   (export "_free" $_free)
@@ -63,7 +64,6 @@
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
   (export "___udivmoddi4" $___udivmoddi4)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_hello_world.fromasm.imprecise

@@ -32,6 +32,7 @@
   (import $_pthread_cleanup_push "env" "_pthread_cleanup_push" (param i32 i32))
   (import $_sysconf "env" "_sysconf" (param i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_i64Subtract" $_i64Subtract)
   (export "_free" $_free)
   (export "_main" $_main)
@@ -55,7 +56,6 @@
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
   (export "___udivmoddi4" $___udivmoddi4)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_hello_world.fromasm.imprecise.no-opts

@@ -32,6 +32,7 @@
   (import $_pthread_cleanup_push "env" "_pthread_cleanup_push" (param i32 i32))
   (import $_sysconf "env" "_sysconf" (param i32) (result i32))
   (import $___syscall146 "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_i64Subtract" $_i64Subtract)
   (export "_free" $_free)
   (export "_main" $_main)
@@ -55,7 +56,6 @@
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
   (export "___udivmoddi4" $___udivmoddi4)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/emcc_hello_world.fromasm.no-opts

@@ -38,6 +38,7 @@
   (import $i32s-rem "asm2wasm" "i32s-rem" (param i32 i32) (result i32))
   (import $i32u-rem "asm2wasm" "i32u-rem" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_i64Subtract" $_i64Subtract)
   (export "_free" $_free)
   (export "_main" $_main)
@@ -61,7 +62,6 @@
   (export "dynCall_iiii" $dynCall_iiii)
   (export "dynCall_vi" $dynCall_vi)
   (export "___udivmoddi4" $___udivmoddi4)
-  (export "memory" memory)
   (global $__THREW__ i32 (i32.const 0))
   (global $threwValue i32 (i32.const 0))
   (global $setjmpId i32 (i32.const 0))

test/empty.fromasm

@@ -1,6 +1,6 @@
 (module
   (memory 256 256)
   (data (get_global $memInitBase) "empty.asm.js")
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
-  (export "memory" memory)
 )

test/empty.fromasm.imprecise

@@ -1,4 +1,4 @@
 (module
   (memory 256 256)
-  (export "memory" memory)
+  (import $memory memory "env" "memory")
 )

test/empty.fromasm.imprecise.no-opts

@@ -1,4 +1,4 @@
 (module
   (memory 256 256)
-  (export "memory" memory)
+  (import $memory memory "env" "memory")
 )

test/empty.fromasm.no-opts

@@ -1,4 +1,4 @@
 (module
   (memory 256 256)
-  (export "memory" memory)
+  (import $memory memory "env" "memory")
 )

test/hello_world.fromasm

@@ -1,9 +1,9 @@
 (module
   (memory 256 256)
   (data (get_global $memInitBase) "hello_world.asm.js")
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "add" $add)
-  (export "memory" memory)
   (func $add (param $0 i32) (param $1 i32) (result i32)
     (i32.add
       (get_local $0)

test/hello_world.fromasm.imprecise

@@ -1,7 +1,7 @@
 (module
   (memory 256 256)
+  (import $memory memory "env" "memory")
   (export "add" $add)
-  (export "memory" memory)
   (func $add (param $0 i32) (param $1 i32) (result i32)
     (i32.add
       (get_local $0)

test/hello_world.fromasm.imprecise.no-opts

@@ -1,7 +1,7 @@
 (module
   (memory 256 256)
+  (import $memory memory "env" "memory")
   (export "add" $add)
-  (export "memory" memory)
   (func $add (param $x i32) (param $y i32) (result i32)
     (return
       (i32.add

test/hello_world.fromasm.no-opts

@@ -1,7 +1,7 @@
 (module
   (memory 256 256)
+  (import $memory memory "env" "memory")
   (export "add" $add)
-  (export "memory" memory)
   (func $add (param $x i32) (param $y i32) (result i32)
     (return
       (i32.add

test/memorygrowth.fromasm

@@ -26,6 +26,7 @@
   (import $xa "env" "___unlock" (param i32))
   (import $ya "env" "___syscall146" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "_free" $fb)
   (export "_main" $Na)
@@ -47,7 +48,6 @@
   (export "dynCall_iiii" $lb)
   (export "dynCall_vi" $mb)
   (export "__growWasmMemory" $__growWasmMemory)
-  (export "memory" memory)
   (global $v i32 (i32.const 0))
   (global $w i32 (i32.const 0))
   (global $x i32 (i32.const 0))

test/memorygrowth.fromasm.imprecise

@@ -24,6 +24,7 @@
   (import $wa "env" "___syscall54" (param i32 i32) (result i32))
   (import $xa "env" "___unlock" (param i32))
   (import $ya "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $fb)
   (export "_main" $Na)
   (export "_pthread_self" $ib)
@@ -44,7 +45,6 @@
   (export "dynCall_iiii" $lb)
   (export "dynCall_vi" $mb)
   (export "__growWasmMemory" $__growWasmMemory)
-  (export "memory" memory)
   (global $v i32 (i32.const 0))
   (global $w i32 (i32.const 0))
   (global $x i32 (i32.const 0))

test/memorygrowth.fromasm.imprecise.no-opts

@@ -24,6 +24,7 @@
   (import $wa "env" "___syscall54" (param i32 i32) (result i32))
   (import $xa "env" "___unlock" (param i32))
   (import $ya "env" "___syscall146" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $fb)
   (export "_main" $Na)
   (export "_pthread_self" $ib)
@@ -44,7 +45,6 @@
   (export "dynCall_iiii" $lb)
   (export "dynCall_vi" $mb)
   (export "__growWasmMemory" $__growWasmMemory)
-  (export "memory" memory)
   (global $v i32 (i32.const 0))
   (global $w i32 (i32.const 0))
   (global $x i32 (i32.const 0))

test/memorygrowth.fromasm.no-opts

@@ -25,6 +25,7 @@
   (import $xa "env" "___unlock" (param i32))
   (import $ya "env" "___syscall146" (param i32 i32) (result i32))
   (import $i32u-div "asm2wasm" "i32u-div" (param i32 i32) (result i32))
+  (import $memory memory "env" "memory")
   (export "_free" $fb)
   (export "_main" $Na)
   (export "_pthread_self" $ib)
@@ -45,7 +46,6 @@
   (export "dynCall_iiii" $lb)
   (export "dynCall_vi" $mb)
   (export "__growWasmMemory" $__growWasmMemory)
-  (export "memory" memory)
   (global $v i32 (i32.const 0))
   (global $w i32 (i32.const 0))
   (global $x i32 (i32.const 0))

test/min.fromasm

@@ -2,9 +2,9 @@
   (memory 256 256)
   (data (get_global $memInitBase) "min.asm.js")
   (import $tDP global "env" "tempDoublePtr" i32)
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "floats" $floats)
-  (export "memory" memory)
   (func $floats (param $0 f32) (result f32)
     (local $1 f32)
     (f32.add

test/min.fromasm.imprecise

@@ -1,8 +1,8 @@
 (module
   (memory 256 256)
   (import $tDP global "env" "tempDoublePtr" i32)
+  (import $memory memory "env" "memory")
   (export "floats" $floats)
-  (export "memory" memory)
   (func $floats (param $0 f32) (result f32)
     (local $1 f32)
     (f32.add

test/min.fromasm.imprecise.no-opts

@@ -1,8 +1,8 @@
 (module
   (memory 256 256)
   (import $tDP global "env" "tempDoublePtr" i32)
+  (import $memory memory "env" "memory")
   (export "floats" $floats)
-  (export "memory" memory)
   (func $floats (param $f f32) (result f32)
     (local $t f32)
     (return

test/min.fromasm.no-opts

@@ -1,8 +1,8 @@
 (module
   (memory 256 256)
   (import $tDP global "env" "tempDoublePtr" i32)
+  (import $memory memory "env" "memory")
   (export "floats" $floats)
-  (export "memory" memory)
   (func $floats (param $f f32) (result f32)
     (local $t f32)
     (return

test/two_sides.fromasm

@@ -3,9 +3,9 @@
   (data (get_global $memInitBase) "two_sides.asm.js")
   (type $FUNCSIG$id (func (param f64) (result i32)))
   (import $f64-to-int "asm2wasm" "f64-to-int" (param f64) (result i32))
+  (import $memory memory "env" "memory")
   (import $memInitBase global "env" "memInitBase" i32)
   (export "_test" $_test)
-  (export "memory" memory)
   (func $_test (param $0 i32) (param $1 i32) (param $2 i32) (param $3 i32) (param $4 i32) (result i32)
     (local $5 f64)
     (if