[x86] Faster/shorter code for stack checks.

test/unittests/compiler/x64/instruction-selector-x64-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "test/unittests/compiler/instruction-selector-unittest.h"
 
 #include "src/compiler/node-matchers.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 1012 matching lines @@
     EXPECT_EQ(kSSEFloat64Sub, s[2]->arch_opcode());
     EXPECT_EQ(kSSEFloat64Div, s[3]->arch_opcode());
   }
 }
 
 
 // -----------------------------------------------------------------------------
 // Miscellaneous.
 
 
+TEST_F(InstructionSelectorTest, Uint64LessThanWithLoadAndLoadStackPointer) {
+  StreamBuilder m(this, kMachBool);
+  Node* const sl = m.Load(
+      kMachPtr,
+      m.ExternalConstant(ExternalReference::address_of_stack_limit(isolate())));
+  Node* const sp = m.LoadStackPointer();
+  Node* const n = m.Uint64LessThan(sl, sp);
+  m.Return(n);
+  Stream s = m.Build();
+  ASSERT_EQ(1U, s.size());
+  EXPECT_EQ(kX64StackCheck, s[0]->arch_opcode());
+  ASSERT_EQ(0U, s[0]->InputCount());
+  ASSERT_EQ(1U, s[0]->OutputCount());
+  EXPECT_EQ(s.ToVreg(n), s.ToVreg(s[0]->Output()));
+  EXPECT_EQ(kFlags_set, s[0]->flags_mode());
+  EXPECT_EQ(kUnsignedGreaterThan, s[0]->flags_condition());
+}
+
+
 TEST_F(InstructionSelectorTest, Word64ShlWithChangeInt32ToInt64) {
   TRACED_FORRANGE(int64_t, x, 32, 63) {
     StreamBuilder m(this, kMachInt64, kMachInt32);
     Node* const p0 = m.Parameter(0);
     Node* const n = m.Word64Shl(m.ChangeInt32ToInt64(p0), m.Int64Constant(x));
     m.Return(n);
     Stream s = m.Build();
     ASSERT_EQ(1U, s.size());
     EXPECT_EQ(kX64Shl, s[0]->arch_opcode());
     ASSERT_EQ(2U, s[0]->InputCount());
@@ skipping 80 matching lines @@
     ASSERT_EQ(1U, s[0]->InputCount());
     EXPECT_EQ(s.ToVreg(p0), s.ToVreg(s[0]->InputAt(0)));
     ASSERT_EQ(1U, s[0]->OutputCount());
     EXPECT_EQ(s.ToVreg(n), s.ToVreg(s[0]->Output()));
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8