Fixes for comparisons between signed and unsigned values with new jb-mr2 compiler (for MIPS, previously fixed for ARM and x86)

Change-Id: Ia2a8f249c57fe073eeb849c4b4814fd2d9cb7ee0
diff --git a/src/oat/runtime/mips/context_mips.cc b/src/oat/runtime/mips/context_mips.cc
index 5f97f6a..cbd63d8 100644
--- a/src/oat/runtime/mips/context_mips.cc
+++ b/src/oat/runtime/mips/context_mips.cc
@@ -69,7 +69,7 @@
 }
 
 void MipsContext::SetGPR(uint32_t reg, uintptr_t value) {
-  CHECK_LT(reg, kNumberOfCoreRegisters);
+  CHECK_LT(reg, static_cast<uint32_t>(kNumberOfCoreRegisters));
   CHECK_NE(gprs_[reg], &gZero); // Can't overwrite this static value since they are never reset.
   CHECK(gprs_[reg] != NULL);
   *gprs_[reg] = value;
diff --git a/src/oat/runtime/mips/context_mips.h b/src/oat/runtime/mips/context_mips.h
index 76a5957..fc8ef96 100644
--- a/src/oat/runtime/mips/context_mips.h
+++ b/src/oat/runtime/mips/context_mips.h
@@ -43,7 +43,7 @@
   }
 
   virtual uintptr_t GetGPR(uint32_t reg) {
-    CHECK_LT(reg, kNumberOfCoreRegisters);
+    CHECK_LT(reg, static_cast<uint32_t>(kNumberOfCoreRegisters));
     return *gprs_[reg];
   }