Merge pull request #243 from WebAssembly/add-memory-export

Add memory exports

Author: jfbastien

ml-proto/README.md

@@ -132,7 +132,7 @@ local:  ( local <type>* ) | ( local <name> <type> )
 module:  ( module <type>* <func>* <import>* <export>* <table>* <memory>? <start>? )
 type:    ( type <name>? ( func <param>* <result>? ) )
 import:  ( import <name>? "<module_name>" "<func_name>" (param <type>* ) (result <type>)* )
-export:  ( export "<char>*" <var> )
+export:  ( export "<char>*" <var> ) | ( export "<char>*" memory)
 start:   ( start <var> )
 table:   ( table <var>* )
 memory:  ( memory <int> <int>? <segment>* )

ml-proto/host/parser.mly

@@ -394,7 +394,9 @@ import :
 
 export :
   | LPAR EXPORT TEXT var RPAR
-    { let at = at () in fun c -> {name = $3; func = $4 c func} @@ at }
+    { let at = at () in fun c -> ExportFunc ($3, ($4 c func)) @@ at }
+  | LPAR EXPORT TEXT MEMORY RPAR
+    { let at = at () in fun c -> ExportMemory $3 @@ at }
 ;
 
 module_fields :

ml-proto/host/print.ml

@@ -21,8 +21,11 @@ let print_var_sig prefix i t =
 let print_func_sig m prefix i f =
   printf "%s %d : %s\n" prefix i (string_of_func_type (func_type m f))
 
-let print_export_sig m prefix n f =
-  printf "%s \"%s\" : %s\n" prefix n (string_of_func_type (func_type m f))
+let print_export_sig m n f =
+  printf "export \"%s\" : %s\n" n (string_of_func_type (func_type m f))
+
+let print_export_mem n =
+  printf "export \"%s\" : memory\n" n
 
 let print_table_elem i x =
   printf "table [%d] = func %d\n" i x.it
@@ -36,7 +39,9 @@ let print_func m i f =
   print_func_sig m "func" i f
 
 let print_export m i ex =
-  print_export_sig m "export" ex.it.name (List.nth m.it.funcs ex.it.func.it)
+  match ex.it with
+  | ExportFunc (n, x) -> print_export_sig m n (List.nth m.it.funcs x.it)
+  | ExportMemory n -> print_export_mem n
 
 let print_module m =
   let {funcs; start; exports; table} = m.it in

ml-proto/spec/check.ml

@@ -289,8 +289,9 @@ let check_elem c x =
 module NameSet = Set.Make(String)
 
 let check_export c set ex =
-  let {name; func = x} = ex.it in
-  ignore (func c x);
+  let name = match ex.it with
+  | ExportFunc (n, x) -> ignore (func c x); n
+  | ExportMemory n -> require (c.has_memory) ex.at "no memory to export"; n in
   require (not (NameSet.mem name set)) ex.at
     "duplicate export name";
   NameSet.add name set

ml-proto/spec/eval.ml

@@ -315,7 +315,9 @@ let init_memory {it = {initial; segments; _}} =
   mem
 
 let add_export funcs ex =
-  ExportMap.add ex.it.name (List.nth funcs ex.it.func.it)
+  match ex.it with
+  | ExportFunc (n, x) -> ExportMap.add n (List.nth funcs x.it)
+  | ExportMemory n -> fun x -> x
 
 let init m imports host =
   assert (List.length imports = List.length m.it.Kernel.imports);

ml-proto/spec/kernel.ml

@@ -126,7 +126,9 @@ and memory' =
 and segment = Memory.segment Source.phrase
 
 type export = export' Source.phrase
-and export' = {name : string; func : var}
+and export' =
+  | ExportFunc of string * var
+  | ExportMemory of string
 
 type import = import' Source.phrase
 and import' =

ml-proto/test/exports.wast

@@ -20,3 +20,7 @@
 )
 
 (assert_return (invoke "e" (i32.const 42)) (i32.const 43))
+
+(module (memory 0 0) (export "a" memory))
+(module (memory 0 0) (export "a" memory) (export "b" memory))
+(assert_invalid (module (export "a" memory)) "no memory to export")