[wasm] Do not create TF nodes during verification

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/zone-containers.h"
@@ skipping 812 matching lines @@
               Push(tval.type, phi);
               ssa_env_->control = merge;
             } else {
               Push(tval.type, nullptr);
             }
             break;
           }
           case kExprBr: {
             BreakDepthOperand operand(this, pc_);
             if (Validate(pc_, operand, control_)) {
-              BreakTo(operand.depth);
+              if (build()) {

[titzer, 2016/10/10 14:16:41]

I don't think this is right place to fix it; it should be deeper inside of
BreakTo().

+                BreakTo(operand.depth);
+              }
             }
             len = 1 + operand.length;
             EndControl();
             break;
           }
           case kExprBrIf: {
             BreakDepthOperand operand(this, pc_);
             Value cond = Pop(0, kAstI32);
             if (ok() && Validate(pc_, operand, control_)) {
               SsaEnv* fenv = ssa_env_;
@@ skipping 1092 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