[wasm] Rework encoding of local declarations.

src/compiler/wasm-compiler.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/compiler/wasm-compiler.h"
 
 #include "src/isolate-inl.h"
 
 #include "src/base/platform/platform.h"
 
@@ skipping 2391 matching lines @@
 // Helper function to compile a single function.
 Handle<Code> CompileWasmFunction(wasm::ErrorThrower& thrower, Isolate* isolate,
                                  wasm::ModuleEnv* module_env,
                                  const wasm::WasmFunction& function) {
   if (FLAG_trace_wasm_compiler || FLAG_trace_wasm_decode_time) {
     OFStream os(stdout);
     os << "Compiling WASM function "
        << wasm::WasmFunctionName(&function, module_env) << std::endl;
     os << std::endl;
   }
-  // Initialize the function environment for decoding.
-  wasm::FunctionEnv env;
-  env.module = module_env;
-  env.sig = function.sig;
-  env.local_i32_count = function.local_i32_count;
-  env.local_i64_count = function.local_i64_count;
-  env.local_f32_count = function.local_f32_count;
-  env.local_f64_count = function.local_f64_count;
-  env.SumLocals();
 
   // Create a TF graph during decoding.
   Zone zone;
   Graph graph(&zone);
   CommonOperatorBuilder common(&zone);
   MachineOperatorBuilder machine(
       &zone, MachineType::PointerRepresentation(),
       InstructionSelector::SupportedMachineOperatorFlags());
   JSGraph jsgraph(isolate, &graph, &common, nullptr, nullptr, &machine);
   WasmGraphBuilder builder(&zone, &jsgraph, function.sig);
-  wasm::TreeResult result = wasm::BuildTFGraph(
-      &builder, &env,                                                 // --
-      module_env->module->module_start,                               // --
-      module_env->module->module_start + function.code_start_offset,  // --
-      module_env->module->module_start + function.code_end_offset);   // --
+  wasm::FunctionBody body = {
+      module_env, function.sig, module_env->module->module_start,
+      module_env->module->module_start + function.code_start_offset,
+      module_env->module->module_start + function.code_end_offset};
+  wasm::TreeResult result = wasm::BuildTFGraph(&builder, body);
 
   if (result.failed()) {
     if (FLAG_trace_wasm_compiler) {
       OFStream os(stdout);
       os << "Compilation failed: " << result << std::endl;
     }
     // Add the function as another context for the exception
     ScopedVector<char> buffer(128);
     SNPrintF(buffer, "Compiling WASM function #%d:%s failed:",
              function.func_index,
@@ skipping 37 matching lines @@
         module_env->module->GetName(function.name_offset));
   }
 
   return code;
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8