MIPS: Allow setting debugger breakpoints on CompareNilICs

Port r14487 (022d1fc3)

BUG=

Review URL: https://codereview.chromium.org/14662002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14509 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/debug-mips.cc

@@ -236,6 +236,15 @@ void Debug::GenerateKeyedStoreICDebugBreak(MacroAssembler* masm) {
 }
 
 
+void Debug::GenerateCompareNilICDebugBreak(MacroAssembler* masm) {
+  // Register state for CompareNil IC
+  // ----------- S t a t e -------------
+  //  -- a0    : value
+  // -----------------------------------
+  Generate_DebugBreakCallHelper(masm, a0.bit(), 0);
+}
+
+
 void Debug::GenerateCallICDebugBreak(MacroAssembler* masm) {
   // Calling convention for IC call (from ic-mips.cc).
   // ----------- S t a t e -------------