[wasm] Encode function signatures, bodies, and names as separate sections.

test/unittests/wasm/module-decoder-unittest.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "test/unittests/test-utils.h"
 
 #include "src/wasm/module-decoder.h"
 #include "src/wasm/wasm-macro-gen.h"
 #include "src/wasm/wasm-opcodes.h"
 
@@ skipping 1041 matching lines @@
   static const byte data[] = {
       kDeclSignatures, 1, VOID_VOID_SIG, kDeclImportTable, 1,
       IMPORT_SIG_INDEX(0),  // sig index
       NAME_LENGTH(1), 'm',  // module name
       NAME_LENGTH(1), 'f',  // function name
   };
 
   EXPECT_OFF_END_FAILURE(data, 5, sizeof(data));
 }
 
-TEST_F(WasmModuleVerifyTest, ExportTable_empty) {
+TEST_F(WasmModuleVerifyTest, ExportTable_empty1) {
+  static const byte data[] = {kDeclSignatures,  1, VOID_VOID_SIG,
+                              kDeclFunctions,   1, EMPTY_FUNCTION(0),
+                              kDeclExportTable, 0};
+  EXPECT_VERIFIES(data);
+}
+
+TEST_F(WasmModuleVerifyTest, ExportTable_empty2) {
   static const byte data[] = {kDeclSignatures,  0, kDeclFunctions, 0,
                               kDeclExportTable, 0};
-  EXPECT_VERIFIES(data);
+  // TODO(titzer): current behavior treats empty functions section as missing.

[binji, 2016/03/09 22:20:17]

OK, so I should emit an empty function section when I add this to sexpr-wasm?

+  EXPECT_FAILURE(data);
 }
 
 TEST_F(WasmModuleVerifyTest, ExportTable_NoFunctions1) {
   static const byte data[] = {kDeclSignatures, 0, kDeclExportTable, 0};
   EXPECT_FAILURE(data);
 }
 
 TEST_F(WasmModuleVerifyTest, ExportTable_NoFunctions2) {
   static const byte data[] = {kDeclExportTable, 0};
   EXPECT_FAILURE(data);
@@ skipping 82 matching lines @@
   for (int length = 13; length < sizeof(data); length++) {
     ModuleResult result = DecodeModule(data, data + length);
     EXPECT_FALSE(result.ok());
     if (result.val) delete result.val;
   }
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8