[wasm] Add stack checks at the beginning of each function.

src/wasm/ast-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/signature.h"
 
 #include "src/bit-vector.h"
 #include "src/flags.h"
 #include "src/handles.h"
 #include "src/zone-containers.h"
@@ skipping 541 matching lines @@
                local_type_vec_[index] == type) {
           // Do a whole run of like-typed locals at a time.
           ssa_env->locals[index++] = node;
         }
       }
       builder_->set_module(module_);
     }
     ssa_env->control = start;
     ssa_env->effect = start;
     SetEnv("initial", ssa_env);
+    if (builder_) {

[titzer, 2016/08/17 11:17:23]

Will the BUILD() macro work here?

[ahaas, 2016/08/17 16:12:57]

Actually not, because InitStackCheck does not return a Node*.

+      builder_->InitStackCheck(position());
+    }
   }
 
   TFNode* DefaultValue(LocalType type) {
     switch (type) {
       case kAstI32:
         return builder_->Int32Constant(0);
       case kAstI64:
         return builder_->Int64Constant(0);
       case kAstF32:
         return builder_->Float32Constant(0);
@@ skipping 1277 matching lines @@
 BitVector* AnalyzeLoopAssignmentForTesting(Zone* zone, size_t num_locals,
                                            const byte* start, const byte* end) {
   FunctionBody body = {nullptr, nullptr, nullptr, start, end};
   WasmFullDecoder decoder(zone, nullptr, body);
   return decoder.AnalyzeLoopAssignmentForTesting(start, num_locals);
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8