[hydrogen] optimize switch with string clauses

src/mips/lithium-codegen-mips.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1710 matching lines @@
   Label* false_label = chunk_->GetAssemblyLabel(false_block);
 
   Condition true_cond =
       EmitIsObject(reg, temp1, false_label, true_label);
 
   EmitBranch(true_block, false_block, true_cond, temp2,
              Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
 }
 
 
+Condition LCodeGen::EmitIsString(Register input,
+                                 Register temp1,
+                                 Label* is_not_string) {
+  __ JumpIfSmi(input, is_not_string);
+  __ GetObjectType(input, temp1, temp1);
+  __ Branch(is_not_string, ge, temp1, Operand(FIRST_NONSTRING_TYPE));
+
+  return lt;
+}
+
+
+void LCodeGen::DoIsStringAndBranch(LIsStringAndBranch* instr) {
+  Register reg = ToRegister(instr->InputAt(0));
+  Register temp1 = ToRegister(instr->TempAt(0));
+  Register temp2 = scratch0();
+
+  int true_block = chunk_->LookupDestination(instr->true_block_id());
+  int false_block = chunk_->LookupDestination(instr->false_block_id());
+  Label* false_label = chunk_->GetAssemblyLabel(false_block);
+
+  Condition true_cond =
+      EmitIsString(reg, temp1, false_label);
+
+  EmitBranch(true_block, false_block, true_cond, temp2,
+             Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
+}
+
+
 void LCodeGen::DoIsSmiAndBranch(LIsSmiAndBranch* instr) {
   int true_block = chunk_->LookupDestination(instr->true_block_id());
   int false_block = chunk_->LookupDestination(instr->false_block_id());
 
   Register input_reg = EmitLoadRegister(instr->InputAt(0), at);
   __ And(at, input_reg, kSmiTagMask);
   EmitBranch(true_block, false_block, eq, at, Operand(zero_reg));
 }
 
 
 void LCodeGen::DoIsUndetectableAndBranch(LIsUndetectableAndBranch* instr) {
   Register input = ToRegister(instr->InputAt(0));
   Register temp = ToRegister(instr->TempAt(0));
 
   int true_block = chunk_->LookupDestination(instr->true_block_id());
   int false_block = chunk_->LookupDestination(instr->false_block_id());
 
   __ JumpIfSmi(input, chunk_->GetAssemblyLabel(false_block));
   __ lw(temp, FieldMemOperand(input, HeapObject::kMapOffset));
   __ lbu(temp, FieldMemOperand(temp, Map::kBitFieldOffset));
   __ And(at, temp, Operand(1 << Map::kIsUndetectable));
   EmitBranch(true_block, false_block, ne, at, Operand(zero_reg));
 }
 
 
+static Condition ComputeCompareCondition(Token::Value op) {
+  switch (op) {
+    case Token::EQ_STRICT:
+    case Token::EQ:
+      return eq;
+    case Token::LT:
+      return lt;
+    case Token::GT:
+      return gt;
+    case Token::LTE:
+      return le;
+    case Token::GTE:
+      return ge;
+    default:
+      UNREACHABLE();
+      return kNoCondition;
+  }
+}
+
+
+void LCodeGen::DoStringCompareAndBranch(LStringCompareAndBranch* instr) {
+  Token::Value op = instr->op();
+  int true_block = chunk_->LookupDestination(instr->true_block_id());
+  int false_block = chunk_->LookupDestination(instr->false_block_id());
+
+  Handle<Code> ic = CompareIC::GetUninitialized(op);
+  CallCode(ic, RelocInfo::CODE_TARGET, instr);
+  // On MIPS there is no need for a "no inlined smi code" marker (nop).
+
+  Condition condition = ComputeCompareCondition(op);
+
+  EmitBranch(true_block, false_block, condition, at,
+             Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
+}
+
+
 static InstanceType TestType(HHasInstanceTypeAndBranch* instr) {
   InstanceType from = instr->from();
   InstanceType to = instr->to();
   if (from == FIRST_TYPE) return to;
   ASSERT(from == to || to == LAST_TYPE);
   return from;
 }
 
 
 static Condition BranchCondition(HHasInstanceTypeAndBranch* instr) {
@@ skipping 277 matching lines @@
   CallCodeGeneric(stub.GetCode(),
                   RelocInfo::CODE_TARGET,
                   instr,
                   RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
   // Put the result value into the result register slot and
   // restore all registers.
   __ StoreToSafepointRegisterSlot(result, result);
 }
 
 
-static Condition ComputeCompareCondition(Token::Value op) {
-  switch (op) {
-    case Token::EQ_STRICT:
-    case Token::EQ:
-      return eq;
-    case Token::LT:
-      return lt;
-    case Token::GT:
-      return gt;
-    case Token::LTE:
-      return le;
-    case Token::GTE:
-      return ge;
-    default:
-      UNREACHABLE();
-      return kNoCondition;
-  }
-}
-
-
 void LCodeGen::DoCmpT(LCmpT* instr) {
   Token::Value op = instr->op();
 
   Handle<Code> ic = CompareIC::GetUninitialized(op);
   CallCode(ic, RelocInfo::CODE_TARGET, instr);
   // On MIPS there is no need for a "no inlined smi code" marker (nop).
 
   Condition condition = ComputeCompareCondition(op);
   // A minor optimization that relies on LoadRoot always emitting one
   // instruction.
@@ skipping 2539 matching lines @@
   ASSERT(!environment->HasBeenRegistered());
   RegisterEnvironmentForDeoptimization(environment);
   ASSERT(osr_pc_offset_ == -1);
   osr_pc_offset_ = masm()->pc_offset();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal