MIPS: Simplify stack check instruction in Crankshaft.

src/mips/lithium-codegen-mips.cc

Index: src/mips/lithium-codegen-mips.cc
diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 32e7dc710da2417c900ec556aba486766a9d0e0c..e0fa7519cb40099c38f50da7fa679433f36d5589 100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -4520,36 +4520,22 @@ void LCodeGen::DoStackCheck(LStackCheck* instr) {
     LStackCheck* instr_;
   };
 
-  ASSERT(instr->HasEnvironment());
-  LEnvironment* env = instr->environment();
+  Register scratch = scratch0();
+  DeferredStackCheck* deferred_stack_check =
+      new DeferredStackCheck(this, instr);
+  __ LoadRoot(scratch, Heap::kStackLimitRootIndex);
+  __ Branch(deferred_stack_check->entry(), lo, sp, Operand(scratch));
+  EnsureSpaceForLazyDeopt();
+  __ bind(instr->done_label());
+  deferred_stack_check->SetExit(instr->done_label());
   // There is no LLazyBailout instruction for stack-checks. We have to
   // prepare for lazy deoptimization explicitly here.
-  if (instr->hydrogen()->is_function_entry()) {
-    // Perform stack overflow check.
-    Label done;
-    __ LoadRoot(at, Heap::kStackLimitRootIndex);
-    __ Branch(&done, hs, sp, Operand(at));
-    StackCheckStub stub;
-    CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
-    EnsureSpaceForLazyDeopt();
-    __ bind(&done);
-    RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
-    safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
-  } else {
-    ASSERT(instr->hydrogen()->is_backwards_branch());
-    // Perform stack overflow check if this goto needs it before jumping.
-    DeferredStackCheck* deferred_stack_check =
-        new DeferredStackCheck(this, instr);
-    __ LoadRoot(at, Heap::kStackLimitRootIndex);
-    __ Branch(deferred_stack_check->entry(), lo, sp, Operand(at));
-    EnsureSpaceForLazyDeopt();
-    __ bind(instr->done_label());
-    deferred_stack_check->SetExit(instr->done_label());
-    RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
-    // Don't record a deoptimization index for the safepoint here.
-    // This will be done explicitly when emitting call and the safepoint in
-    // the deferred code.
-  }
+  ASSERT(instr->HasEnvironment());
+  LEnvironment* env = instr->environment();
+  RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
+  // Don't record a deoptimization index for the safepoint here.
+  // This will be done explicitly when emitting call and the safepoint in
+  // the deferred code.
 }