host ops

4 files changed, 28 insertions, 4 deletions

diff --git a/src/wasm-interpreter.h b/src/wasm-interpreter.h
index 0ca4d9674..5279e8a35 100644
--- a/src/wasm-interpreter.h
+++ b/src/wasm-interpreter.h
@@ -43,6 +43,7 @@ public:
     virtual Literal callImport(Import* import, LiteralList& arguments) = 0;
     virtual Literal load(Load* load, size_t addr) = 0;
     virtual void store(Store* store, size_t addr, Literal value) = 0;
+    virtual void growMemory(size_t oldSize, size_t newSize) = 0;
     virtual void trap() = 0;
   };
 
@@ -634,11 +635,18 @@ public:
       }
       Flow visitHost(Host *curr) override {
         NOTE_ENTER("Host");
-
         switch (curr->op) {
           case PageSize:   return Literal(64*1024);
           case MemorySize: return Literal(instance.memorySize);
-          case GrowMemory: abort();
+          case GrowMemory: {
+            Flow flow = visit(curr->operands[0]);
+            if (flow.breaking()) return flow;
+            size_t newSize = flow.value.getInteger();
+            if (newSize > instance.wasm.memory.max) trap();
+            instance.externalInterface->growMemory(instance.memorySize, newSize);
+            instance.memorySize = newSize;
+            return Literal();
+          }
           case HasFeature: {
             IString id = curr->nameOperand;
             if (id == WASM) return Literal(1);
diff --git a/src/wasm-js.cpp b/src/wasm-js.cpp
index 44c5cb099..ddb31b33d 100644
--- a/src/wasm-js.cpp
+++ b/src/wasm-js.cpp
@@ -173,6 +173,10 @@ extern "C" void EMSCRIPTEN_KEEPALIVE load_asm(char *input) {
       }
     }
 
+    void growMemory(size_t oldSize, size_t newSize) override {
+      abort();
+    }
+
     void trap() override {
       EM_ASM({
         abort("wasm trap!");
diff --git a/src/wasm-s-parser.h b/src/wasm-s-parser.h
index b81800ad2..58f316075 100644
--- a/src/wasm-s-parser.h
+++ b/src/wasm-s-parser.h
@@ -500,6 +500,7 @@ public:
         }
         case 'g': {
           if (str[1] == 'e') return makeGetLocal(s);
+          if (str[1] == 'r') return makeHost(s, HostOp::GrowMemory);
           abort_on(str);
         }
         case 'h': {
@@ -515,10 +516,18 @@ public:
           if (str[1] == 'o') return makeLoop(s);
           abort_on(str);
         }
+        case 'm': {
+          if (str[1] == 'e') return makeHost(s, HostOp::MemorySize);
+          abort_on(str);
+        }
         case 'n': {
           if (str[1] == 'o') return allocator.alloc<Nop>();
           abort_on(str);
         }
+        case 'p': {
+          if (str[1] == 'a') return makeHost(s, HostOp::PageSize);
+          abort_on(str);
+        }
         case 's': {
           if (str[1] == 'e') return makeSetLocal(s);
           abort_on(str);
diff --git a/src/wasm-shell.cpp b/src/wasm-shell.cpp
index c37ba79a3..5f9fafd8f 100644
--- a/src/wasm-shell.cpp
+++ b/src/wasm-shell.cpp
@@ -24,13 +24,11 @@ IString ASSERT_RETURN("assert_return"),
 
 struct ShellExternalInterface : ModuleInstance::ExternalInterface {
   char *memory;
-  size_t memorySize;
 
   ShellExternalInterface() : memory(nullptr) {}
 
   void init(Module& wasm) override {
     memory = new char[wasm.memory.initial];
-    memorySize = wasm.memory.initial;
     // apply memory segments
     for (auto segment : wasm.memory.segments) {
       memcpy(memory + segment.offset, segment.data, segment.size);
@@ -104,6 +102,11 @@ struct ShellExternalInterface : ModuleInstance::ExternalInterface {
     }
   }
 
+  void growMemory(size_t oldSize, size_t newSize) override {
+    delete memory;
+    memory = new char[newSize];
+  }
+
   jmp_buf trapState;
 
   void trap() override {