Enhance CHECK_EQ and friends to allow extra detail to be appended (like CHECK).

Change-Id: Iaa980892ab31621c8bcca9ea7c6c4ee743333f45
diff --git a/src/compiler/codegen/arm/ArchUtility.cc b/src/compiler/codegen/arm/ArchUtility.cc
index edce114..aef98fa 100644
--- a/src/compiler/codegen/arm/ArchUtility.cc
+++ b/src/compiler/codegen/arm/ArchUtility.cc
@@ -122,7 +122,7 @@
                 strcpy(tbuf, "!");
             } else {
                DCHECK_LT(fmt, fmtEnd);
-               DCHECK((unsigned)(nc-'0') < 4);
+               DCHECK_LT((unsigned)(nc-'0'), 4U);
                operand = lir->operands[nc-'0'];
                switch(*fmt++) {
                    case 'H':
diff --git a/src/compiler/codegen/arm/Thumb2/Factory.cc b/src/compiler/codegen/arm/Thumb2/Factory.cc
index 318be5a..1ea565a 100644
--- a/src/compiler/codegen/arm/Thumb2/Factory.cc
+++ b/src/compiler/codegen/arm/Thumb2/Factory.cc
@@ -341,7 +341,7 @@
             LOG(FATAL) << "Bad opcode: " << (int)op;
             break;
     }
-    DCHECK(opcode >= 0);
+    DCHECK_GE(static_cast<int>(opcode), 0);
     if (EncodingMap[opcode].flags & IS_BINARY_OP)
         return newLIR2(cUnit, opcode, rDestSrc1, rSrc2);
     else if (EncodingMap[opcode].flags & IS_TERTIARY_OP) {
@@ -418,7 +418,7 @@
             LOG(FATAL) << "Bad opcode: " << (int)op;
             break;
     }
-    DCHECK(opcode >= 0);
+    DCHECK_GE(static_cast<int>(opcode), 0);
     if (EncodingMap[opcode].flags & IS_QUAD_OP)
         return newLIR4(cUnit, opcode, rDest, rSrc1, rSrc2, shift);
     else {