wasm - replace the WLL section with support to skip all unknown sections.

src/wasm/module-decoder.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 "src/macro-assembler.h"
 #include "src/objects.h"
 #include "src/v8.h"
 
 #include "src/wasm/decoder.h"
 #include "src/wasm/module-decoder.h"
@@ skipping 216 matching lines @@
               error(sigpos, "invalid signature index");
             } else {
               import->sig = module->signatures->at(import->sig_index);
             }
             import->module_name_offset = consume_string("import module name");
             import->function_name_offset =
                 consume_string("import function name");
           }
           break;
         }
-        case kDeclWLL: {
-          // Reserved for experimentation by the Web Low-level Language project
-          // which is augmenting the binary encoding with source code meta
-          // information. This section does not affect the semantics of the code
-          // and can be ignored by the runtime. https://github.com/JSStats/wll
-          int length = 0;
-          uint32_t section_size = consume_u32v(&length, "section size");
+        default:
+          // All other sections are ignored and skipped. Known experimental
+          // sections: 0x11 WLL https://github.com/JSStats/wll
+          uint32_t section_size = consume_u32("section size");
           if (pc_ + section_size > limit_ || pc_ + section_size < pc_) {
-            error(pc_ - length, "invalid section size");
+            error(pc_ - 4, "invalid section size");
             break;
           }
           pc_ += section_size;
           break;
-        }
-        default:
-          error(pc_ - 1, nullptr, "unrecognized section 0x%02x", section);
-          break;
       }
     }
 
     return toResult(module);
   }
 
   uint32_t SafeReserve(uint32_t count) {
     // Avoid OOM by only reserving up to a certain size.
     const uint32_t kMaxReserve = 20000;
     return count < kMaxReserve ? count : kMaxReserve;
@@ skipping 343 matching lines @@
   if (function_start > function_end) return FunctionError("start > end");
   if (size > kMaxFunctionSize)
     return FunctionError("size > maximum function size");
   WasmFunction* function = new WasmFunction();
   ModuleDecoder decoder(zone, function_start, function_end, false);
   return decoder.DecodeSingleFunction(module_env, function);
 }
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8