[wasm] Do not support grow_memory for asmjs modules.

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 1211 matching lines @@
             break;
           case kExprI64StoreMem:
             len = DecodeStoreMem(kAstI64, MachineType::Int64());
             break;
           case kExprF32StoreMem:
             len = DecodeStoreMem(kAstF32, MachineType::Float32());
             break;
           case kExprF64StoreMem:
             len = DecodeStoreMem(kAstF64, MachineType::Float64());
             break;
-
+          case kExprGrowMemory:
+            if (module_->origin != kAsmJsOrigin) {
+              Push(kAstI32, BUILD(GrowMemory, Pop(0, kAstI32).node));
+              break;
+            } else {
+              error("grow_memory is not supported for asmjs modules");
+              return;

[titzer, 2016/09/08 08:16:29]

No need to return here; the error will cause the main decoder loop to break.

[ahaas, 2016/09/09 10:52:28]

Done.

+            }
           case kExprMemorySize:
             Push(kAstI32, BUILD(MemSize, 0));
             break;
           case kExprCallFunction: {
             CallFunctionOperand operand(this, pc_);
             if (Validate(pc_, operand)) {
               TFNode** buffer = PopArgs(operand.sig);
               TFNode* call =
                   BUILD(CallDirect, operand.index, buffer, position());
               Push(GetReturnType(operand.sig), call);
@@ skipping 29 matching lines @@
             CHECK_PROTOTYPE_OPCODE(wasm_simd_prototype);
             len++;
             byte simd_index = *(pc_ + 1);
             opcode = static_cast<WasmOpcode>(opcode << 8 | simd_index);
             TRACE("  @%-4d #%02x #%02x:%-20s|", startrel(pc_), kSimdPrefix,
                   simd_index, WasmOpcodes::ShortOpcodeName(opcode));
             DecodeSimdOpcode(opcode);
             break;
           }
           default:
-            error("Invalid opcode");
-            return;
+            // Deal with special asmjs opcodes.
+            if (module_->origin == kAsmJsOrigin) {
+              sig = WasmOpcodes::AsmjsSignature(opcode);
+              if (sig) {
+                // Fast case of a simple operator.
+                TFNode* node;

[titzer, 2016/09/08 08:16:29]

Factor this switch out to an inline method?

[ahaas, 2016/09/09 10:52:28]

Done.

+                switch (sig->parameter_count()) {
+                  case 1: {
+                    Value val = Pop(0, sig->GetParam(0));
+                    node = BUILD(Unop, opcode, val.node, position());
+                    break;
+                  }
+                  case 2: {
+                    Value rval = Pop(1, sig->GetParam(1));
+                    Value lval = Pop(0, sig->GetParam(0));
+                    node =
+                        BUILD(Binop, opcode, lval.node, rval.node, position());
+                    break;
+                  }
+                  default:
+                    UNREACHABLE();
+                    node = nullptr;
+                    break;
+                }
+                Push(GetReturnType(sig), node);
+              }
+            } else {
+              error("Invalid opcode");
+              return;
+            }
         }
       }  // end complex bytecode
 
 #if DEBUG
       if (FLAG_trace_wasm_decoder) {
         for (size_t i = 0; i < stack_.size(); ++i) {
           Value& val = stack_[i];
           WasmOpcode opcode = static_cast<WasmOpcode>(*val.pc);
           if (WasmOpcodes::IsPrefixOpcode(opcode)) {
             opcode = static_cast<WasmOpcode>(opcode << 8 | *(val.pc + 1));
@@ skipping 780 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