Import memory instead of defining/exporting it when using emscripten glue (#777)

The emscripten JS module code creates the memory using the native wasm
APIs, and imports that into the wasm module.

1 files changed, 15 insertions, 12 deletions

diff --git a/src/wasm-linker.h b/src/wasm-linker.h
index 4a0e1e0b9..3660b3038 100644
--- a/src/wasm-linker.h
+++ b/src/wasm-linker.h
@@ -193,18 +193,18 @@ class LinkerObject {
 // applying the relocations, resulting in an executable wasm module.
 class Linker {
  public:
-  Linker(Address globalBase, Address stackAllocation,
-         Address userInitialMemory, Address userMaxMemory,
-         bool ignoreUnknownSymbols, Name startFunction,
-         bool debug) :
-      ignoreUnknownSymbols(ignoreUnknownSymbols),
-      startFunction(startFunction),
-      globalBase(globalBase),
-      nextStatic(globalBase),
-      userInitialMemory(userInitialMemory),
-      userMaxMemory(userMaxMemory),
-      stackAllocation(stackAllocation),
-      debug(debug) {
+  Linker(Address globalBase, Address stackAllocation, Address userInitialMemory,
+         Address userMaxMemory, bool importMemory, bool ignoreUnknownSymbols,
+         Name startFunction, bool debug)
+      : ignoreUnknownSymbols(ignoreUnknownSymbols),
+        startFunction(startFunction),
+        globalBase(globalBase),
+        nextStatic(globalBase),
+        userInitialMemory(userInitialMemory),
+        userMaxMemory(userMaxMemory),
+        importMemory(importMemory),
+        stackAllocation(stackAllocation),
+        debug(debug) {
     if (userMaxMemory && userMaxMemory < userInitialMemory) {
       Fatal() << "Specified max memory " << userMaxMemory <<
           " is < specified initial memory " << userInitialMemory;
@@ -217,6 +217,7 @@ class Linker {
       Fatal() << "Specified initial memory " << userInitialMemory <<
           " is not a multiple of 64k";
     }
+
     // Don't allow anything to be allocated at address 0
     if (globalBase == 0) nextStatic = 1;
 
@@ -312,6 +313,8 @@ class Linker {
   Address userInitialMemory; // Initial memory size (in bytes) specified by the user.
   Address userMaxMemory; // Max memory size (in bytes) specified by the user.
   //(after linking, this is rounded and set on the wasm object in pages)
+  bool importMemory;  // Whether the memory should be imported instead of
+                      // defined.
   Address stackAllocation;
   bool debug;