save module and base of mapped imported globals, and fix writing of mapped imported globals

3 files changed, 31 insertions, 11 deletions

diff --git a/src/asm2wasm.h b/src/asm2wasm.h
index 2bb76610b..e5ba3a499 100644
--- a/src/asm2wasm.h
+++ b/src/asm2wasm.h
@@ -79,14 +79,18 @@ class Asm2WasmBuilder {
     unsigned address;
     WasmType type;
     bool import; // if true, this is an import - we should read the value, not just set a zero
+    IString module, base;
     MappedGlobal() : address(0), type(none), import(false) {}
-    MappedGlobal(unsigned address, WasmType type, bool import) : address(address), type(type), import(import) {}
+    MappedGlobal(unsigned address, WasmType type, bool import, IString module, IString base) : address(address), type(type), import(import), module(module), base(base) {}
   };
+
+public:
   std::map<IString, MappedGlobal> mappedGlobals;
 
-  void allocateGlobal(IString name, WasmType type, bool import) {
+private:
+  void allocateGlobal(IString name, WasmType type, bool import, IString module = IString(), IString base = IString()) {
     assert(mappedGlobals.find(name) == mappedGlobals.end());
-    mappedGlobals.emplace(name, MappedGlobal(nextGlobal, type, import));
+    mappedGlobals.emplace(name, MappedGlobal(nextGlobal, type, import, module, base));
     nextGlobal += 8;
     assert(nextGlobal < maxGlobal);
   }
@@ -369,7 +373,7 @@ void Asm2WasmBuilder::processAsm(Ref ast) {
     }
     if (type != WasmType::none) {
       // wasm has no imported constants, so allocate a global, and we need to write the value into that
-      allocateGlobal(name, type, true);
+      allocateGlobal(name, type, true, import.module, import.base);
     } else {
       wasm.imports.emplace(name, import);
     }
diff --git a/src/js/post.js b/src/js/post.js
index c9e29f6e8..2ecec51aa 100644
--- a/src/js/post.js
+++ b/src/js/post.js
@@ -41,8 +41,8 @@
       lookup = (lookup || {})[parts[1]];
     }
     lookup = (lookup || {})[base];
-    if (!lookup) {
-      abort('bad CallImport to (' + mod + ').' + base);
+    if (lookup === undefined) {
+      abort('bad lookupImport to (' + mod + ').' + base);
     }
     return lookup;
   }
diff --git a/src/wasm-js.cpp b/src/wasm-js.cpp
index bedc65d48..14dfa563c 100644
--- a/src/wasm-js.cpp
+++ b/src/wasm-js.cpp
@@ -15,7 +15,10 @@
 using namespace cashew;
 using namespace wasm;
 
+// global singletons
+Asm2WasmBuilder* asm2wasm = nullptr;
 ModuleInstance* instance = nullptr;
+Module* module = nullptr;
 
 // receives asm.js code, parses into wasm and returns an instance handle.
 // this creates a module, an external interface, a builder, and a module instance,
@@ -49,22 +52,22 @@ extern "C" void EMSCRIPTEN_KEEPALIVE load_asm(char *input) {
   cashew::Parser<Ref, DotZeroValueBuilder> builder;
   Ref asmjs = builder.parseToplevel(input);
 
-  Module* wasm = new Module();
+  module = new Module();
 
   if (debug) std::cerr << "wasming...\n";
-  Asm2WasmBuilder* asm2wasm = new Asm2WasmBuilder(*wasm);
+  asm2wasm = new Asm2WasmBuilder(*module);
   asm2wasm->processAsm(asmjs);
 
   if (debug) std::cerr << "optimizing...\n";
   asm2wasm->optimize();
 
-  //std::cerr << *wasm << '\n';
+  //std::cerr << *module << '\n';
 
   if (debug) std::cerr << "generating exports...\n";
   EM_ASM({
     Module['asmExports'] = {};
   });
-  for (auto& curr : wasm->exports) {
+  for (auto& curr : module->exports) {
     EM_ASM_({
       var name = Pointer_stringify($0);
       Module['asmExports'][name] = function() {
@@ -159,11 +162,24 @@ extern "C" void EMSCRIPTEN_KEEPALIVE load_asm(char *input) {
     }
   };
 
-  instance = new ModuleInstance(*wasm, new JSExternalInterface());
+  instance = new ModuleInstance(*module, new JSExternalInterface());
 }
 
 // Ready the provided imported globals, copying them to their mapped locations.
 extern "C" void EMSCRIPTEN_KEEPALIVE load_mapped_globals() {
+  for (auto& pair : asm2wasm->mappedGlobals) {
+    auto name = pair.first;
+    auto& global = pair.second;
+    if (!global.import) continue; // non-imports are initialized to zero in the typed array anyhow, so nothing to do here
+    double value = EM_ASM_DOUBLE({ return Module['lookupImport'](Pointer_stringify($0), Pointer_stringify($1)) }, global.module.str, global.base.str);
+    unsigned address = global.address;
+    switch (global.type) {
+      case i32: EM_ASM_({ Module['info'].parent['HEAP32'][$0] = $1 }, address, value); break;
+      case f32: EM_ASM_({ Module['info'].parent['HEAPF32'][$0] = $1 }, address, value); break;
+      case f64: EM_ASM_({ Module['info'].parent['HEAPF64'][$0] = $1 }, address, value); break;
+      default: abort();
+    }
+  }
 }
 
 // Does a call from js into an export of the module.