Avoids MIPS32r2 instructions on MIPS32.

runtime/vm/cpu_mips.cc

 // Copyright (c) 2013, 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_MIPS)
 
 #include "vm/cpu.h"
 #include "vm/cpuinfo.h"
@@ skipping 23 matching lines @@
 const char* CPU::Id() {
   return
 #if !defined(HOST_ARCH_MIPS)
   "sim"
 #endif  // !defined(HOST_ARCH_MIPS)
   "mips";
 }
 
 
 const char* HostCPUFeatures::hardware_ = NULL;
+MIPSVersion HostCPUFeatures::mips_version_ = MIPSvUnknown;
 #if defined(DEBUG)
 bool HostCPUFeatures::initialized_ = false;
 #endif
 
 
 #if defined(HOST_ARCH_MIPS)
 void HostCPUFeatures::InitOnce() {
   CpuInfo::InitOnce();
   hardware_ = CpuInfo::GetCpuModel();
   // Has a floating point unit.
   ASSERT(CpuInfo::FieldContains(kCpuInfoModel, "FPU"));
+
+  // We want to know the ISA version, but on MIPS, CpuInfo can't tell us, so
+  // we use the same ISA version that Dart's C++ compiler targeted.
+#if defined(_MIPS_ARCH_MIPS32R2)
+  mips_version_ = MIPS32r2;
+#elif defined(_MIPS_ARCH_MIPS32)
+  mips_version_ = MIPS32;
+#endif
+
 #if defined(DEBUG)
   initialized_ = true;
 #endif
 }
 
 
 void HostCPUFeatures::Cleanup() {
   DEBUG_ASSERT(initialized_);
 #if defined(DEBUG)
   initialized_ = false;
 #endif
   ASSERT(hardware_ != NULL);
   free(const_cast<char*>(hardware_));
   hardware_ = NULL;
   CpuInfo::Cleanup();
 }
 
 #else
 
 void HostCPUFeatures::InitOnce() {
   CpuInfo::InitOnce();
   hardware_ = CpuInfo::GetCpuModel();
+  mips_version_ = MIPS32r2;
 #if defined(DEBUG)
   initialized_ = true;
 #endif
 }
 
 
 void HostCPUFeatures::Cleanup() {
   DEBUG_ASSERT(initialized_);
 #if defined(DEBUG)
   initialized_ = false;
 #endif
   ASSERT(hardware_ != NULL);
   free(const_cast<char*>(hardware_));
   hardware_ = NULL;
   CpuInfo::Cleanup();
 }
 #endif  // defined(HOST_ARCH_MIPS)
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS