Only require SSE2 at minimum hardware requirement.

runtime/vm/assembler_x64.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/heap.h"
 #include "vm/memory_region.h"
 #include "vm/runtime_entry.h"
 #include "vm/stub_code.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, print_stop_message, true, "Print stop message.");
 DEFINE_FLAG(bool, code_comments, false,
             "Include comments into code and disassembly");
 DEFINE_FLAG(bool, use_sse41, true, "Use SSE 4.1 if available");
 
 
-bool CPUFeatures::sse3_supported_ = false;
 bool CPUFeatures::sse4_1_supported_ = false;
 #ifdef DEBUG
 bool CPUFeatures::initialized_ = false;
 #endif
 
-bool CPUFeatures::sse3_supported() {
-  DEBUG_ASSERT(initialized_);
-  return sse3_supported_;
-}
-
-
 bool CPUFeatures::sse4_1_supported() {
   DEBUG_ASSERT(initialized_);
   return sse4_1_supported_ && FLAG_use_sse41;
 }
 
 
 #define __ assembler.
 
 void CPUFeatures::InitOnce() {
   Assembler assembler;
@@ skipping 12 matching lines @@
   __ popq(RBX);
   __ popq(RBP);
   __ ret();
 
   const Code& code =
       Code::Handle(Code::FinalizeCode("DetectCPUFeatures", &assembler));
   Instructions& instructions = Instructions::Handle(code.instructions());
   typedef uint64_t (*DetectCPUFeatures)();
   uint64_t features =
       reinterpret_cast<DetectCPUFeatures>(instructions.EntryPoint())();
-  sse3_supported_ = (features & kSSE3BitMask) != 0;
   sse4_1_supported_ = (features & kSSE4_1BitMask) != 0;
 #ifdef DEBUG
   initialized_ = true;
 #endif
 }
 
 #undef __
 
 
 void Assembler::InitializeMemoryWithBreakpoints(uword data, int length) {
@@ skipping 2041 matching lines @@
 
 const char* Assembler::XmmRegisterName(XmmRegister reg) {
   ASSERT((0 <= reg) && (reg < kNumberOfXmmRegisters));
   return xmm_reg_names[reg];
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64