Use count-based profiling exclusively.

src/mips/deoptimizer-mips.cc

Index: src/mips/deoptimizer-mips.cc
diff --git a/src/mips/deoptimizer-mips.cc b/src/mips/deoptimizer-mips.cc
index 9fd815bb428dbdfb4179fbeed5267046b50e723f..e8ed9ccf7bf0c0c7e040c1be603973f7cb513bb1 100644
--- a/src/mips/deoptimizer-mips.cc
+++ b/src/mips/deoptimizer-mips.cc
@@ -120,7 +120,7 @@ void Deoptimizer::PatchStackCheckCodeAt(Code* unoptimized_code,
                                         Code* check_code,
                                         Code* replacement_code) {
   const int kInstrSize = Assembler::kInstrSize;
-  // This structure comes from FullCodeGenerator::EmitStackCheck.
+  // This structure comes from FullCodeGenerator::EmitBackEdgeBookkeeping.
   // The call of the stack guard check has the following form:
   // sltu at, sp, t0 / slt at, a3, zero_reg (in case of count based interrupts)
   // beq at, zero_reg, ok
@@ -170,11 +170,7 @@ void Deoptimizer::RevertStackCheckCodeAt(Code* unoptimized_code,
 
   // Restore the sltu instruction so beq can be taken again.
   CodePatcher patcher(pc_after - 6 * kInstrSize, 1);
-  if (FLAG_count_based_interrupts) {
-    patcher.masm()->slt(at, a3, zero_reg);
-  } else {
-    patcher.masm()->sltu(at, sp, t0);
-  }
+  patcher.masm()->slt(at, a3, zero_reg);
 
   // Replace the on-stack replacement address in the load-immediate (lui/ori
   // pair) with the entry address of the normal stack-check code.