Revert "ARM: Improve register allocation and constraints."

src/arm/lithium-arm.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 805 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoBit(Token::Value op,
                                    HBitwiseBinaryOperation* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());
     ASSERT(instr->right()->representation().IsInteger32());
 
     LOperand* left = UseRegisterAtStart(instr->LeastConstantOperand());
     LOperand* right = UseOrConstantAtStart(instr->MostConstantOperand());
-    return DefineAsRegister(new LBitI(op, left, right));
+    return DefineSameAsFirst(new LBitI(op, left, right));
   } else {
     ASSERT(instr->representation().IsTagged());
     ASSERT(instr->left()->representation().IsTagged());
     ASSERT(instr->right()->representation().IsTagged());
 
     LOperand* left = UseFixed(instr->left(), r1);
     LOperand* right = UseFixed(instr->right(), r0);
     LArithmeticT* result = new LArithmeticT(op, left, right);
     return MarkAsCall(DefineFixed(result, r0), instr);
   }
@@ skipping 18 matching lines @@
   LOperand* left = UseRegisterAtStart(instr->OperandAt(0));
 
   HValue* right_value = instr->OperandAt(1);
   LOperand* right = NULL;
   int constant_value = 0;
   if (right_value->IsConstant()) {
     HConstant* constant = HConstant::cast(right_value);
     right = chunk_->DefineConstantOperand(constant);
     constant_value = constant->Integer32Value() & 0x1f;
   } else {
-    right = UseRegisterAtStart(right_value);
+    right = UseRegister(right_value);
   }
 
   // Shift operations can only deoptimize if we do a logical shift
   // by 0 and the result cannot be truncated to int32.
   bool may_deopt = (op == Token::SHR && constant_value == 0);
   bool does_deopt = false;
   if (may_deopt) {
     for (HUseIterator it(instr->uses()); !it.Done(); it.Advance()) {
       if (!it.value()->CheckFlag(HValue::kTruncatingToInt32)) {
         does_deopt = true;
         break;
       }
     }
   }
 
   LInstruction* result =
-      DefineAsRegister(new LShiftI(op, left, right, does_deopt));
+      DefineSameAsFirst(new LShiftI(op, left, right, does_deopt));
   return does_deopt ? AssignEnvironment(result) : result;
 }
 
 
 LInstruction* LChunkBuilder::DoArithmeticD(Token::Value op,
                                            HArithmeticBinaryOperation* instr) {
   ASSERT(instr->representation().IsDouble());
   ASSERT(instr->left()->representation().IsDouble());
   ASSERT(instr->right()->representation().IsDouble());
   ASSERT(op != Token::MOD);
   LOperand* left = UseRegisterAtStart(instr->left());
   LOperand* right = UseRegisterAtStart(instr->right());
   LArithmeticD* result = new LArithmeticD(op, left, right);
-  return DefineAsRegister(result);
+  return DefineSameAsFirst(result);
 }
 
 
 LInstruction* LChunkBuilder::DoArithmeticT(Token::Value op,
                                            HArithmeticBinaryOperation* instr) {
   ASSERT(op == Token::ADD ||
          op == Token::DIV ||
          op == Token::MOD ||
          op == Token::MUL ||
          op == Token::SUB);
@@ skipping 323 matching lines @@
   if (op == kMathLog || op == kMathSin || op == kMathCos) {
     LOperand* input = UseFixedDouble(instr->value(), d2);
     LUnaryMathOperation* result = new LUnaryMathOperation(input, NULL);
     return MarkAsCall(DefineFixedDouble(result, d2), instr);
   } else {
     LOperand* input = UseRegisterAtStart(instr->value());
     LOperand* temp = (op == kMathFloor) ? TempRegister() : NULL;
     LUnaryMathOperation* result = new LUnaryMathOperation(input, temp);
     switch (op) {
       case kMathAbs:
-        return AssignEnvironment(AssignPointerMap(DefineAsRegister(result)));
+        return AssignEnvironment(AssignPointerMap(DefineSameAsFirst(result)));
       case kMathFloor:
         return AssignEnvironment(AssignPointerMap(DefineAsRegister(result)));
       case kMathSqrt:
-        return DefineAsRegister(result);
+        return DefineSameAsFirst(result);
       case kMathRound:
         return AssignEnvironment(DefineAsRegister(result));
       case kMathPowHalf:
-        return DefineAsRegister(result);
+        return DefineSameAsFirst(result);
       default:
         UNREACHABLE();
         return NULL;
     }
   }
 }
 
 
 LInstruction* LChunkBuilder::DoCallKeyed(HCallKeyed* instr) {
   ASSERT(instr->key()->representation().IsTagged());
@@ skipping 57 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoBitAnd(HBitAnd* instr) {
   return DoBit(Token::BIT_AND, instr);
 }
 
 
 LInstruction* LChunkBuilder::DoBitNot(HBitNot* instr) {
   ASSERT(instr->value()->representation().IsInteger32());
   ASSERT(instr->representation().IsInteger32());
-  return DefineAsRegister(new LBitNotI(UseRegisterAtStart(instr->value())));
+  return DefineSameAsFirst(new LBitNotI(UseRegisterAtStart(instr->value())));
 }
 
 
 LInstruction* LChunkBuilder::DoBitOr(HBitOr* instr) {
   return DoBit(Token::BIT_OR, instr);
 }
 
 
 LInstruction* LChunkBuilder::DoBitXor(HBitXor* instr) {
   return DoBit(Token::BIT_XOR, instr);
@@ skipping 28 matching lines @@
     if (instr->HasPowerOf2Divisor()) {
       ASSERT(!instr->CheckFlag(HValue::kCanBeDivByZero));
       LOperand* value = UseRegisterAtStart(instr->left());
       mod = new LModI(value, UseOrConstant(instr->right()));
     } else {
       LOperand* dividend = UseRegister(instr->left());
       LOperand* divisor = UseRegisterAtStart(instr->right());
       mod = new LModI(dividend,
                       divisor,
                       TempRegister(),
-                      FixedTemp(d10),
-                      FixedTemp(d11));
+                      FixedTemp(d1),
+                      FixedTemp(d2));
     }
 
-    bool needs_env = (instr->CheckFlag(HValue::kBailoutOnMinusZero) ||
-                      instr->CheckFlag(HValue::kCanBeDivByZero));
-    return needs_env ? AssignEnvironment(DefineAsRegister(mod))
-                     : DefineAsRegister(mod);
+    return AssignEnvironment(DefineSameAsFirst(mod));
   } else if (instr->representation().IsTagged()) {
     return DoArithmeticT(Token::MOD, instr);
   } else {
     ASSERT(instr->representation().IsDouble());
     // We call a C function for double modulo. It can't trigger a GC.
     // We need to use fixed result register for the call.
     // TODO(fschneider): Allow any register as input registers.
     LOperand* left = UseFixedDouble(instr->left(), d1);
     LOperand* right = UseFixedDouble(instr->right(), d2);
     LArithmeticD* result = new LArithmeticD(Token::MOD, left, right);
     return MarkAsCall(DefineFixedDouble(result, d1), instr);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoMul(HMul* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());
     ASSERT(instr->right()->representation().IsInteger32());
-    LOperand* left;
+    LOperand* left = UseRegisterAtStart(instr->LeastConstantOperand());
     LOperand* right = UseOrConstant(instr->MostConstantOperand());
     LOperand* temp = NULL;
     if (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
         (instr->CheckFlag(HValue::kCanOverflow) ||
         !right->IsConstantOperand())) {
-      left = UseRegister(instr->LeastConstantOperand());
       temp = TempRegister();
-    } else {
-      left = UseRegisterAtStart(instr->LeastConstantOperand());
     }
-    return AssignEnvironment(DefineAsRegister(new LMulI(left, right, temp)));
+    return AssignEnvironment(DefineSameAsFirst(new LMulI(left, right, temp)));
 
   } else if (instr->representation().IsDouble()) {
     return DoArithmeticD(Token::MUL, instr);
 
   } else {
     return DoArithmeticT(Token::MUL, instr);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoSub(HSub* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());
     ASSERT(instr->right()->representation().IsInteger32());
     LOperand* left = UseRegisterAtStart(instr->left());
     LOperand* right = UseOrConstantAtStart(instr->right());
     LSubI* sub = new LSubI(left, right);
-    LInstruction* result = DefineAsRegister(sub);
+    LInstruction* result = DefineSameAsFirst(sub);
     if (instr->CheckFlag(HValue::kCanOverflow)) {
       result = AssignEnvironment(result);
     }
     return result;
   } else if (instr->representation().IsDouble()) {
     return DoArithmeticD(Token::SUB, instr);
   } else {
     return DoArithmeticT(Token::SUB, instr);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoAdd(HAdd* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());
     ASSERT(instr->right()->representation().IsInteger32());
     LOperand* left = UseRegisterAtStart(instr->LeastConstantOperand());
     LOperand* right = UseOrConstantAtStart(instr->MostConstantOperand());
     LAddI* add = new LAddI(left, right);
-    LInstruction* result = DefineAsRegister(add);
+    LInstruction* result = DefineSameAsFirst(add);
     if (instr->CheckFlag(HValue::kCanOverflow)) {
       result = AssignEnvironment(result);
     }
     return result;
   } else if (instr->representation().IsDouble()) {
     return DoArithmeticD(Token::ADD, instr);
   } else {
     ASSERT(instr->representation().IsTagged());
     return DoArithmeticT(Token::ADD, instr);
   }
@@ skipping 145 matching lines @@
 
 LInstruction* LChunkBuilder::DoElementsKind(HElementsKind* instr) {
   LOperand* object = UseRegisterAtStart(instr->value());
   return DefineAsRegister(new LElementsKind(object));
 }
 
 
 LInstruction* LChunkBuilder::DoValueOf(HValueOf* instr) {
   LOperand* object = UseRegister(instr->value());
   LValueOf* result = new LValueOf(object, TempRegister());
-  return AssignEnvironment(DefineAsRegister(result));
+  return AssignEnvironment(DefineSameAsFirst(result));
 }
 
 
 LInstruction* LChunkBuilder::DoBoundsCheck(HBoundsCheck* instr) {
   return AssignEnvironment(new LBoundsCheck(UseRegisterAtStart(instr->index()),
                                             UseRegister(instr->length())));
 }
 
 
 LInstruction* LChunkBuilder::DoAbnormalExit(HAbnormalExit* instr) {
@@ skipping 34 matching lines @@
       ASSERT(to.IsInteger32());
       LOperand* value = UseRegister(instr->value());
       bool needs_check = !instr->value()->type().IsSmi();
       LInstruction* res = NULL;
       if (!needs_check) {
         res = DefineSameAsFirst(new LSmiUntag(value, needs_check));
       } else {
         LOperand* temp1 = TempRegister();
         LOperand* temp2 = instr->CanTruncateToInt32() ? TempRegister()
                                                       : NULL;
-        LOperand* temp3 = instr->CanTruncateToInt32() ? FixedTemp(d11)
+        LOperand* temp3 = instr->CanTruncateToInt32() ? FixedTemp(d3)
                                                       : NULL;
         res = DefineSameAsFirst(new LTaggedToI(value, temp1, temp2, temp3));
         res = AssignEnvironment(res);
       }
       return res;
     }
   } else if (from.IsDouble()) {
     if (to.IsTagged()) {
       LOperand* value = UseRegister(instr->value());
       LOperand* temp1 = TempRegister();
@@ skipping 73 matching lines @@
   LInstruction* result = new LCheckMap(value);
   return AssignEnvironment(result);
 }
 
 
 LInstruction* LChunkBuilder::DoClampToUint8(HClampToUint8* instr) {
   HValue* value = instr->value();
   Representation input_rep = value->representation();
   LOperand* reg = UseRegister(value);
   if (input_rep.IsDouble()) {
-    return DefineAsRegister(new LClampDToUint8(reg, FixedTemp(d11)));
+    return DefineAsRegister(new LClampDToUint8(reg, FixedTemp(d1)));
   } else if (input_rep.IsInteger32()) {
     return DefineAsRegister(new LClampIToUint8(reg));
   } else {
     ASSERT(input_rep.IsTagged());
     // Register allocator doesn't (yet) support allocation of double
     // temps. Reserve d1 explicitly.
-    LClampTToUint8* result = new LClampTToUint8(reg, FixedTemp(d11));
+    LClampTToUint8* result = new LClampTToUint8(reg, FixedTemp(d1));
     return AssignEnvironment(DefineAsRegister(result));
   }
 }
 
 
 LInstruction* LChunkBuilder::DoToInt32(HToInt32* instr) {
   HValue* value = instr->value();
   Representation input_rep = value->representation();
   LOperand* reg = UseRegister(value);
   if (input_rep.IsDouble()) {
     LOperand* temp1 = TempRegister();
     LOperand* temp2 = TempRegister();
     LDoubleToI* res = new LDoubleToI(reg, temp1, temp2);
     return AssignEnvironment(DefineAsRegister(res));
   } else if (input_rep.IsInteger32()) {
     // Canonicalization should already have removed the hydrogen instruction in
     // this case, since it is a noop.
     UNREACHABLE();
     return NULL;
   } else {
     ASSERT(input_rep.IsTagged());
     LOperand* temp1 = TempRegister();
     LOperand* temp2 = TempRegister();
-    LOperand* temp3 = FixedTemp(d11);
+    LOperand* temp3 = FixedTemp(d3);
     LTaggedToI* res = new LTaggedToI(reg, temp1, temp2, temp3);
     return AssignEnvironment(DefineSameAsFirst(res));
   }
 }
 
 
 LInstruction* LChunkBuilder::DoReturn(HReturn* instr) {
   return new LReturn(UseFixed(instr->value(), r0));
 }
 
@@ skipping 117 matching lines @@
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedFastElement(
     HLoadKeyedFastElement* instr) {
   ASSERT(instr->representation().IsTagged());
   ASSERT(instr->key()->representation().IsInteger32());
   LOperand* obj = UseRegisterAtStart(instr->object());
   LOperand* key = UseRegisterAtStart(instr->key());
   LLoadKeyedFastElement* result = new LLoadKeyedFastElement(obj, key);
-  return AssignEnvironment(DefineAsRegister(result));
+  return AssignEnvironment(DefineSameAsFirst(result));
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedSpecializedArrayElement(
     HLoadKeyedSpecializedArrayElement* instr) {
   JSObject::ElementsKind elements_kind = instr->elements_kind();
   Representation representation(instr->representation());
   ASSERT(
       (representation.IsInteger32() &&
        (elements_kind != JSObject::EXTERNAL_FLOAT_ELEMENTS) &&
@@ skipping 294 matching lines @@
 
 LInstruction* LChunkBuilder::DoIn(HIn* instr) {
   LOperand* key = UseRegisterAtStart(instr->key());
   LOperand* object = UseRegisterAtStart(instr->object());
   LIn* result = new LIn(key, object);
   return MarkAsCall(DefineFixed(result, r0), instr);
 }
 
 
 } }  // namespace v8::internal