Adds mrc instruction to arm simulator, assembler, disassembler.

runtime/vm/assembler_arm.cc

Index: runtime/vm/assembler_arm.cc
===================================================================
--- runtime/vm/assembler_arm.cc	(revision 19404)
+++ runtime/vm/assembler_arm.cc	(working copy)
@@ -1116,6 +1116,29 @@
 }
 
 
+void Assembler::mrc(Register rd, int32_t coproc, int32_t opc1,
+                    int32_t CRn, int32_t CRm, int32_t opc2, Condition cond) {

[regis, 2013/03/04 21:54:52]

crn, crm

+  ASSERT(rd != kNoRegister);
+  ASSERT(cond != kNoCondition);
+
+  // This is all the simulator and disassembler know about.
+  ASSERT(coproc == 15);
+  ASSERT(opc1 == 0);
+  ASSERT(CRn == 0);
+  ASSERT(CRm == 2);
+  ASSERT(opc2 == 0);
+  int32_t encoding = (static_cast<int32_t>(cond) << kConditionShift) |
+                     B27 | B26 | B25 | B20 | B4 |
+                     ((opc1 & 0x7) << kOpc1Shift) |
+                     ((CRn & 0xf) << kCRnShift) |
+                     ((coproc & 0xf) << kCoprocShift) |
+                     ((opc2 & 0x7) << kOpc2Shift) |
+                     ((CRm & 0xf) << kCRmShift) |
+                     (static_cast<int32_t>(rd) << kRdShift);
+  Emit(encoding);
+}
+
+
 void Assembler::MarkExceptionHandler(Label* label) {
   EmitType01(AL, 1, TST, 1, PC, R0, ShifterOperand(0));
   Label l;