Implement heap poisoning in ART's Optimizing compiler.

- Instrument ARM, ARM64, x86 and x86-64 code generators.
- Note: To turn heap poisoning on in Optimizing, set the
  environment variable `ART_HEAP_POISONING' to "true"
  before compiling ART.

Bug: 12687968
Change-Id: Ib3120b38cf805a8a50207a314b9ccc90c8d93740
diff --git a/compiler/utils/mips64/assembler_mips64.cc b/compiler/utils/mips64/assembler_mips64.cc
index 3333cd2..24ea9e2 100644
--- a/compiler/utils/mips64/assembler_mips64.cc
+++ b/compiler/utils/mips64/assembler_mips64.cc
@@ -1242,12 +1242,12 @@
 }
 
 void Mips64Assembler::LoadRef(ManagedRegister mdest, ManagedRegister base, MemberOffset offs,
-                              bool poison_reference) {
+                              bool unpoison_reference) {
   Mips64ManagedRegister dest = mdest.AsMips64();
   CHECK(dest.IsGpuRegister() && base.AsMips64().IsGpuRegister());
   LoadFromOffset(kLoadUnsignedWord, dest.AsGpuRegister(),
                  base.AsMips64().AsGpuRegister(), offs.Int32Value());
-  if (kPoisonHeapReferences && poison_reference) {
+  if (kPoisonHeapReferences && unpoison_reference) {
     // TODO: review
     // Negate the 32-bit ref
     Dsubu(dest.AsGpuRegister(), ZERO, dest.AsGpuRegister());
diff --git a/compiler/utils/mips64/assembler_mips64.h b/compiler/utils/mips64/assembler_mips64.h
index 88cc4bc..47b146a 100644
--- a/compiler/utils/mips64/assembler_mips64.h
+++ b/compiler/utils/mips64/assembler_mips64.h
@@ -265,7 +265,7 @@
   void LoadRef(ManagedRegister dest, FrameOffset src) OVERRIDE;
 
   void LoadRef(ManagedRegister mdest, ManagedRegister base, MemberOffset offs,
-               bool poison_reference) OVERRIDE;
+               bool unpoison_reference) OVERRIDE;
 
   void LoadRawPtr(ManagedRegister mdest, ManagedRegister base, Offset offs) OVERRIDE;