[v8-dev] ARM: Optimize TypeofIsAndBranch

src/arm/macro-assembler-arm.cc

Index: src/arm/macro-assembler-arm.cc
diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc
index 47d42a3122073e988ee8985047244a19a51e8b67..9242c743e26a657d2faad4275221afa14b0e64f0 100644
--- a/src/arm/macro-assembler-arm.cc
+++ b/src/arm/macro-assembler-arm.cc
@@ -2016,14 +2016,36 @@ void MacroAssembler::CompareObjectType(Register object,
                                        Register map,
                                        Register type_reg,
                                        InstanceType type) {
+  const Register temp = type_reg.is(no_reg) ? ip : type_reg;
+
+  ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
+  CompareInstanceType(map, temp, type);
+}
+
+
+void MacroAssembler::CheckObjectTypeRange(Register object,
+                                          Register map,
+                                          InstanceType min_type,
+                                          InstanceType max_type,
+                                          Label* false_label) {
+  STATIC_ASSERT(Map::kInstanceTypeOffset < 4096);
+  STATIC_ASSERT(LAST_TYPE < 256);
   ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
-  CompareInstanceType(map, type_reg, type);
+  ldrb(ip, FieldMemOperand(map, Map::kInstanceTypeOffset));
+  sub(ip, ip, Operand(min_type));
+  cmp(ip, Operand(max_type - min_type));
+  b(hi, false_label);
 }
 
 
 void MacroAssembler::CompareInstanceType(Register map,
                                          Register type_reg,
                                          InstanceType type) {
+  // Registers map and type_reg can be ip. These two lines assert
+  // that ip can be used with the two instructions (the constants
+  // won't never need ip).

[ulan, 2013/11/22 15:43:46]

nit: either "won't ever need" or "will never need".

+  STATIC_ASSERT(Map::kInstanceTypeOffset < 4096);
+  STATIC_ASSERT(LAST_TYPE < 256);
   ldrb(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
   cmp(type_reg, Operand(type));
 }