[wasm] Implement decoding of i32v values

src/wasm/wasm-module-builder.h

 // 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.
 
 #ifndef V8_WASM_WASM_MODULE_BUILDER_H_
 #define V8_WASM_WASM_MODULE_BUILDER_H_
 
 #include "src/signature.h"
 #include "src/zone/zone-containers.h"
 
@@ skipping 31 matching lines @@
     EnsureSpace(4);
     WriteLittleEndianValue<uint32_t>(pos_, x);
     pos_ += 4;
   }
 
   void write_u32v(uint32_t val) {
     EnsureSpace(kMaxVarInt32Size);
     LEBHelper::write_u32v(&pos_, val);
   }
 
+  void write_i32v(int32_t val) {
+    EnsureSpace(kMaxVarInt32Size);
+    LEBHelper::write_i32v(&pos_, val);
+  }
+
   void write_size(size_t val) {
     EnsureSpace(kMaxVarInt32Size);
     DCHECK_EQ(val, static_cast<uint32_t>(val));
     LEBHelper::write_u32v(&pos_, static_cast<uint32_t>(val));
   }
 
   void write(const byte* data, size_t size) {
     EnsureSpace(size);
     memcpy(pos_, data, size);
     pos_ += size;
@@ skipping 202 matching lines @@
 
 inline FunctionSig* WasmFunctionBuilder::signature() {
   return builder_->signatures_[signature_index_];
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_WASM_MODULE_BUILDER_H_