Use type info for the ToBoolean translation in crankshaft.

src/ia32/lithium-codegen-ia32.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 1374 matching lines @@
     Register reg = ToRegister(instr->InputAt(0));
     __ test(reg, Operand(reg));
     EmitBranch(true_block, false_block, not_zero);
   } else if (r.IsDouble()) {
     XMMRegister reg = ToDoubleRegister(instr->InputAt(0));
     __ xorps(xmm0, xmm0);
     __ ucomisd(reg, xmm0);
     EmitBranch(true_block, false_block, not_equal);
   } else {
     ASSERT(r.IsTagged());
+    Factory* factory = this->factory();
     Register reg = ToRegister(instr->InputAt(0));
     if (instr->hydrogen()->value()->type().IsBoolean()) {
-      __ cmp(reg, factory()->true_value());
+      __ cmp(reg, factory->true_value());
       EmitBranch(true_block, false_block, equal);
     } else {
       Label* true_label = chunk_->GetAssemblyLabel(true_block);
       Label* false_label = chunk_->GetAssemblyLabel(false_block);
 
-      __ cmp(reg, factory()->undefined_value());
-      __ j(equal, false_label);
-      __ cmp(reg, factory()->true_value());
-      __ j(equal, true_label);
-      __ cmp(reg, factory()->false_value());
-      __ j(equal, false_label);
-      __ test(reg, Operand(reg));
-      __ j(equal, false_label);
-      __ JumpIfSmi(reg, true_label);
+      ToBooleanStub::Types expected = instr->hydrogen()->expected_input_types();
+      // Avoid deopts in the case where we've never executed this path before.
+      if (expected.IsEmpty()) expected = ToBooleanStub::all_types();
 
-      // Test for double values. Zero is false.
-      Label call_stub;
-      __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-             factory()->heap_number_map());
-      __ j(not_equal, &call_stub, Label::kNear);
-      __ fldz();
-      __ fld_d(FieldOperand(reg, HeapNumber::kValueOffset));
-      __ FCmp();
-      __ j(zero, false_label);
-      __ jmp(true_label);
+      if (expected.Contains(ToBooleanStub::UNDEFINED)) {
+        // undefined -> false.
+        __ cmp(reg, factory->undefined_value());
+        __ j(equal, false_label);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen undefined for the first time -> deopt.
+        __ cmp(reg, factory->undefined_value());
+        DeoptimizeIf(equal, instr->environment());
+      }
 
-      // The conversion stub doesn't cause garbage collections so it's
-      // safe to not record a safepoint after the call.
-      __ bind(&call_stub);
-      ToBooleanStub stub(eax, ToBooleanStub::all_types());
-      __ pushad();
-      __ push(reg);
-      __ CallStub(&stub);
-      __ test(eax, Operand(eax));
-      __ popad();
-      EmitBranch(true_block, false_block, not_zero);
+      if (expected.Contains(ToBooleanStub::BOOLEAN)) {
+        // true -> true.
+        __ cmp(reg, factory->true_value());
+        __ j(equal, true_label);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen a string for the first time -> deopt.
+        __ cmp(reg, factory->true_value());
+        DeoptimizeIf(equal, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::BOOLEAN)) {
+        // false -> false.
+        __ cmp(reg, factory->false_value());
+        __ j(equal, false_label);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen a string for the first time -> deopt.
+        __ cmp(reg, factory->false_value());
+        DeoptimizeIf(equal, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::NULL_TYPE)) {
+        // 'null' -> false.
+        __ cmp(reg, factory->null_value());
+        __ j(equal, false_label);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen null for the first time -> deopt.
+        __ cmp(reg, factory->null_value());
+        DeoptimizeIf(equal, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::SMI)) {
+        // Smis: 0 -> false, all other -> true.
+        __ test(reg, Operand(reg));
+        __ j(equal, false_label);
+        __ JumpIfSmi(reg, true_label);
+      } else if (expected.NeedsMap()) {
+        // If we need a map later and have a Smi -> deopt.
+        __ test(reg, Immediate(kSmiTagMask));
+        DeoptimizeIf(zero, instr->environment());
+      }
+
+      Register map;
+      if (expected.NeedsMap()) {
+        map = ToRegister(instr->TempAt(0));
+        ASSERT(!map.is(reg));
+        __ mov(map, FieldOperand(reg, HeapObject::kMapOffset));
+        // Everything with a map could be undetectable, so check this now.
+        __ test_b(FieldOperand(map, Map::kBitFieldOffset),
+                  1 << Map::kIsUndetectable);
+        // Undetectable -> false.
+        __ j(not_zero, false_label);
+      }
+
+      if (expected.Contains(ToBooleanStub::SPEC_OBJECT)) {
+        // spec object -> true.
+        __ CmpInstanceType(map, FIRST_SPEC_OBJECT_TYPE);
+        __ j(above_equal, true_label);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen a spec object for the first time -> deopt.
+        __ CmpInstanceType(map, FIRST_SPEC_OBJECT_TYPE);
+        DeoptimizeIf(above_equal, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::STRING)) {
+        // String value -> false iff empty.
+        Label not_string;
+        __ CmpInstanceType(map, FIRST_NONSTRING_TYPE);
+        __ j(above_equal, &not_string, Label::kNear);
+        __ cmp(FieldOperand(reg, String::kLengthOffset), Immediate(0));
+        __ j(not_zero, true_label);
+        __ jmp(false_label);
+        __ bind(&not_string);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen a string for the first time -> deopt
+        __ CmpInstanceType(map, FIRST_NONSTRING_TYPE);
+        DeoptimizeIf(below, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::HEAP_NUMBER)) {
+        // heap number -> false iff +0, -0, or NaN.
+        Label not_heap_number;
+        __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
+               factory->heap_number_map());
+        __ j(not_equal, &not_heap_number, Label::kNear);
+        __ fldz();
+        __ fld_d(FieldOperand(reg, HeapNumber::kValueOffset));
+        __ FCmp();
+        __ j(zero, false_label);
+        __ jmp(true_label);
+        __ bind(&not_heap_number);
+      } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // We've seen a heap number for the first time -> deopt.
+        __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
+               factory->heap_number_map());
+        DeoptimizeIf(equal, instr->environment());
+      }
+
+      if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+        // internal objects -> true
+        __ jmp(true_label);
+      } else {
+        // We've seen something for the first time -> deopt.
+        DeoptimizeIf(no_condition, instr->environment());
+      }
     }
   }
 }
 
 
 void LCodeGen::EmitGoto(int block) {
   block = chunk_->LookupDestination(block);
   int next_block = GetNextEmittedBlock(current_block_);
   if (block != next_block) {
     __ jmp(chunk_->GetAssemblyLabel(block));
@@ skipping 2864 matching lines @@
                                          env->deoptimization_index());
   __ InvokeBuiltin(Builtins::IN, CALL_FUNCTION, safepoint_generator);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32