Make initial and max memory sizes be in pages instead of bytes

The AST and everything that uses it treats the values as
pages. Javascript continues to use bytes.
This matches v8 and sexpr-wasm, and the consensus from live discussion
and  PR209 in the spec.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/wasm.h b/src/wasm.h
index 6cbe93e3b..ce6b9d294 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -1074,6 +1074,8 @@ public:
 
 class Memory {
 public:
+  static const size_t kPageSize = 64 * 1024;
+  static const size_t kPageMask = ~(kPageSize - 1);
   struct Segment {
     size_t offset;
     const char* data;
@@ -1082,7 +1084,7 @@ public:
     Segment(size_t offset, const char *data, size_t size) : offset(offset), data(data), size(size) {}
   };
 
-  size_t initial, max;
+  size_t initial, max; // sizes are in pages
   std::vector<Segment> segments;
 
   Memory() : initial(0), max((uint32_t)-1) {}