Add inlining of binary smi operations in the full codegens on IA32

and x64 (on IA32 we even fold constants into the instructions for
a more compact representation) and prepare the ARM full codegen for
the doing the same there.
Review URL: http://codereview.chromium.org/3195028

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5351 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/full-codegen-arm.cc

@@ -246,6 +246,13 @@ void FullCodeGenerator::EmitReturnSequence() {
 }
 
 
+FullCodeGenerator::ConstantOperand FullCodeGenerator::GetConstantOperand(
+    Token::Value op, Expression* left, Expression* right) {
+  ASSERT(ShouldInlineSmiCase(op));
+  return kNoConstants;
+}
+
+
 void FullCodeGenerator::Apply(Expression::Context context, Register reg) {
   switch (context) {
     case Expression::kUninitialized:
@@ -1144,10 +1151,11 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
   // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
-  Property* prop = expr->target()->AsProperty();
-  if (prop != NULL) {
-    assign_type =
-        (prop->key()->IsPropertyName()) ? NAMED_PROPERTY : KEYED_PROPERTY;
+  Property* property = expr->target()->AsProperty();
+  if (property != NULL) {
+    assign_type = (property->key()->IsPropertyName())
+        ? NAMED_PROPERTY
+        : KEYED_PROPERTY;
   }
 
   // Evaluate LHS expression.
@@ -1158,61 +1166,70 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
     case NAMED_PROPERTY:
       if (expr->is_compound()) {
         // We need the receiver both on the stack and in the accumulator.
-        VisitForValue(prop->obj(), kAccumulator);
+        VisitForValue(property->obj(), kAccumulator);
         __ push(result_register());
       } else {
-        VisitForValue(prop->obj(), kStack);
+        VisitForValue(property->obj(), kStack);
       }
       break;
     case KEYED_PROPERTY:
-      // We need the key and receiver on both the stack and in r0 and r1.
       if (expr->is_compound()) {
-        VisitForValue(prop->obj(), kStack);
-        VisitForValue(prop->key(), kAccumulator);
+        VisitForValue(property->obj(), kStack);
+        VisitForValue(property->key(), kAccumulator);
         __ ldr(r1, MemOperand(sp, 0));
         __ push(r0);
       } else {
-        VisitForValue(prop->obj(), kStack);
-        VisitForValue(prop->key(), kStack);
+        VisitForValue(property->obj(), kStack);
+        VisitForValue(property->key(), kStack);
       }
       break;
   }
 
-  // If we have a compound assignment: Get value of LHS expression and
-  // store in on top of the stack.
   if (expr->is_compound()) {
     Location saved_location = location_;
-    location_ = kStack;
+    location_ = kAccumulator;
     switch (assign_type) {
       case VARIABLE:
         EmitVariableLoad(expr->target()->AsVariableProxy()->var(),
                          Expression::kValue);
         break;
       case NAMED_PROPERTY:
-        EmitNamedPropertyLoad(prop);
-        __ push(result_register());
+        EmitNamedPropertyLoad(property);
         break;
       case KEYED_PROPERTY:
-        EmitKeyedPropertyLoad(prop);
-        __ push(result_register());
+        EmitKeyedPropertyLoad(property);
         break;
     }
-    location_ = saved_location;
-  }
 
-  // Evaluate RHS expression.
-  Expression* rhs = expr->value();
-  VisitForValue(rhs, kAccumulator);
+    Token::Value op = expr->binary_op();
+    ConstantOperand constant = ShouldInlineSmiCase(op)
+        ? GetConstantOperand(op, expr->target(), expr->value())
+        : kNoConstants;
+    ASSERT(constant == kRightConstant || constant == kNoConstants);
+    if (constant == kNoConstants) {
+      __ push(r0);  // Left operand goes on the stack.
+      VisitForValue(expr->value(), kAccumulator);
+    }
 
-  // If we have a compound assignment: Apply operator.
-  if (expr->is_compound()) {
-    Location saved_location = location_;
-    location_ = kAccumulator;
     OverwriteMode mode = expr->value()->ResultOverwriteAllowed()
         ? OVERWRITE_RIGHT
         : NO_OVERWRITE;
-    EmitBinaryOp(expr->binary_op(), Expression::kValue, mode);
+    SetSourcePosition(expr->position() + 1);
+    if (ShouldInlineSmiCase(op)) {
+      EmitInlineSmiBinaryOp(expr,
+                            op,
+                            Expression::kValue,
+                            mode,
+                            expr->target(),
+                            expr->value(),
+                            constant);
+    } else {
+      EmitBinaryOp(op, Expression::kValue, mode);
+    }
     location_ = saved_location;
+
+  } else {
+    VisitForValue(expr->value(), kAccumulator);
   }
 
   // Record source position before possible IC call.
@@ -1253,6 +1270,18 @@ void FullCodeGenerator::EmitKeyedPropertyLoad(Property* prop) {
 }
 
 
+void FullCodeGenerator::EmitInlineSmiBinaryOp(Expression* expr,
+                                              Token::Value op,
+                                              Expression::Context context,
+                                              OverwriteMode mode,
+                                              Expression* left,
+                                              Expression* right,
+                                              ConstantOperand constant) {
+  ASSERT(constant == kNoConstants);  // Only handled case.
+  EmitBinaryOp(op, context, mode);
+}
+
+
 void FullCodeGenerator::EmitBinaryOp(Token::Value op,
                                      Expression::Context context,
                                      OverwriteMode mode) {

src/ast.h

@@ -205,6 +205,9 @@ class Expression: public AstNode {
   // False for operations that can return one of their operands.
   virtual bool ResultOverwriteAllowed() { return false; }
 
+  // True iff the expression is a literal represented as a smi.
+  virtual bool IsSmiLiteral() { return false; }
+
   // Static type information for this expression.
   StaticType* type() { return &type_; }
 
@@ -775,6 +778,7 @@ class Literal: public Expression {
 
   virtual void Accept(AstVisitor* v);
   virtual bool IsTrivial() { return true; }
+  virtual bool IsSmiLiteral() { return handle_->IsSmi(); }
 
   // Type testing & conversion.
   virtual Literal* AsLiteral() { return this; }

src/full-codegen.cc

@@ -516,18 +516,21 @@ void FullCodeGenerator::EmitInlineRuntimeCall(CallRuntime* expr) {
 
 void FullCodeGenerator::VisitBinaryOperation(BinaryOperation* expr) {
   Comment cmnt(masm_, "[ BinaryOperation");
-
-  OverwriteMode overwrite_mode = NO_OVERWRITE;
-  if (expr->left()->ResultOverwriteAllowed()) {
-    overwrite_mode = OVERWRITE_LEFT;
-  } else if (expr->right()->ResultOverwriteAllowed()) {
-    overwrite_mode = OVERWRITE_RIGHT;
+  Token::Value op = expr->op();
+  Expression* left = expr->left();
+  Expression* right = expr->right();
+
+  OverwriteMode mode = NO_OVERWRITE;
+  if (left->ResultOverwriteAllowed()) {
+    mode = OVERWRITE_LEFT;
+  } else if (right->ResultOverwriteAllowed()) {
+    mode = OVERWRITE_RIGHT;
   }
 
-  switch (expr->op()) {
+  switch (op) {
     case Token::COMMA:
-      VisitForEffect(expr->left());
-      Visit(expr->right());
+      VisitForEffect(left);
+      Visit(right);
       break;
 
     case Token::OR:
@@ -545,12 +548,31 @@ void FullCodeGenerator::VisitBinaryOperation(BinaryOperation* expr) {
     case Token::BIT_XOR:
     case Token::SHL:
     case Token::SHR:
-    case Token::SAR:
-      VisitForValue(expr->left(), kStack);
-      VisitForValue(expr->right(), kAccumulator);
+    case Token::SAR: {
+      // Figure out if either of the operands is a constant.
+      ConstantOperand constant = ShouldInlineSmiCase(op)
+          ? GetConstantOperand(op, left, right)
+          : kNoConstants;
+
+      // Load only the operands that we need to materialize.
+      if (constant == kNoConstants) {
+        VisitForValue(left, kStack);
+        VisitForValue(right, kAccumulator);
+      } else if (constant == kRightConstant) {
+        VisitForValue(left, kAccumulator);
+      } else {
+        ASSERT(constant == kLeftConstant);
+        VisitForValue(right, kAccumulator);
+      }
+
       SetSourcePosition(expr->position());
-      EmitBinaryOp(expr->op(), context_, overwrite_mode);
+      if (ShouldInlineSmiCase(op)) {
+        EmitInlineSmiBinaryOp(expr, op, context_, mode, left, right, constant);
+      } else {
+        EmitBinaryOp(op, context_, mode);
+      }
       break;
+    }
 
     default:
       UNREACHABLE();

src/full-codegen.h

@@ -237,6 +237,12 @@ class FullCodeGenerator: public AstVisitor {
     kStack
   };
 
+  enum ConstantOperand {
+    kNoConstants,
+    kLeftConstant,
+    kRightConstant
+  };
+
   // Compute the frame pointer relative offset for a given local or
   // parameter slot.
   int SlotOffset(Slot* slot);
@@ -245,6 +251,11 @@ class FullCodeGenerator: public AstVisitor {
   // operation.
   bool ShouldInlineSmiCase(Token::Value op);
 
+  // Compute which (if any) of the operands is a compile-time constant.
+  ConstantOperand GetConstantOperand(Token::Value op,
+                                     Expression* left,
+                                     Expression* right);
+
   // Emit code to convert a pure value (in a register, slot, as a literal,
   // or on top of the stack) into the result expected according to an
   // expression context.
@@ -361,7 +372,6 @@ class FullCodeGenerator: public AstVisitor {
   void EmitCallWithIC(Call* expr, Handle<Object> name, RelocInfo::Mode mode);
   void EmitKeyedCallWithIC(Call* expr, Expression* key, RelocInfo::Mode mode);
 
-
   // Platform-specific code for inline runtime calls.
   void EmitInlineRuntimeCall(CallRuntime* expr);
 
@@ -393,6 +403,47 @@ class FullCodeGenerator: public AstVisitor {
                     Expression::Context context,
                     OverwriteMode mode);
 
+  // Helper functions for generating inlined smi code for certain
+  // binary operations.
+  void EmitInlineSmiBinaryOp(Expression* expr,
+                             Token::Value op,
+                             Expression::Context context,
+                             OverwriteMode mode,
+                             Expression* left,
+                             Expression* right,
+                             ConstantOperand constant);
+
+  void EmitConstantSmiBinaryOp(Expression* expr,
+                               Token::Value op,
+                               Expression::Context context,
+                               OverwriteMode mode,
+                               bool left_is_constant_smi,
+                               Smi* value);
+
+  void EmitConstantSmiBitOp(Expression* expr,
+                            Token::Value op,
+                            Expression::Context context,
+                            OverwriteMode mode,
+                            Smi* value);
+
+  void EmitConstantSmiShiftOp(Expression* expr,
+                              Token::Value op,
+                              Expression::Context context,
+                              OverwriteMode mode,
+                              Smi* value);
+
+  void EmitConstantSmiAdd(Expression* expr,
+                          Expression::Context context,
+                          OverwriteMode mode,
+                          bool left_is_constant_smi,
+                          Smi* value);
+
+  void EmitConstantSmiSub(Expression* expr,
+                          Expression::Context context,
+                          OverwriteMode mode,
+                          bool left_is_constant_smi,
+                          Smi* value);
+
   // Assign to the given expression as if via '='. The right-hand-side value
   // is expected in the accumulator.
   void EmitAssignment(Expression* expr);

src/token.h

@@ -248,6 +248,10 @@ class Token {
     return op == INC || op == DEC;
   }
 
+  static bool IsShiftOp(Value op) {
+    return (SHL <= op) && (op <= SHR);
+  }
+
   // Returns a string corresponding to the JS token string
   // (.e., "<" for the token LT) or NULL if the token doesn't
   // have a (unique) string (e.g. an IDENTIFIER).

src/x64/full-codegen-x64.cc

@@ -230,6 +230,13 @@ void FullCodeGenerator::EmitReturnSequence() {
 }
 
 
+FullCodeGenerator::ConstantOperand FullCodeGenerator::GetConstantOperand(
+    Token::Value op, Expression* left, Expression* right) {
+  ASSERT(ShouldInlineSmiCase(op));
+  return kNoConstants;
+}
+
+
 void FullCodeGenerator::Apply(Expression::Context context, Register reg) {
   switch (context) {
     case Expression::kUninitialized:
@@ -1156,10 +1163,11 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
   // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
-  Property* prop = expr->target()->AsProperty();
-  if (prop != NULL) {
-    assign_type =
-        (prop->key()->IsPropertyName()) ? NAMED_PROPERTY : KEYED_PROPERTY;
+  Property* property = expr->target()->AsProperty();
+  if (property != NULL) {
+    assign_type = (property->key()->IsPropertyName())
+        ? NAMED_PROPERTY
+        : KEYED_PROPERTY;
   }
 
   // Evaluate LHS expression.
@@ -1170,60 +1178,70 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
     case NAMED_PROPERTY:
       if (expr->is_compound()) {
         // We need the receiver both on the stack and in the accumulator.
-        VisitForValue(prop->obj(), kAccumulator);
+        VisitForValue(property->obj(), kAccumulator);
         __ push(result_register());
       } else {
-        VisitForValue(prop->obj(), kStack);
+        VisitForValue(property->obj(), kStack);
       }
       break;
     case KEYED_PROPERTY:
       if (expr->is_compound()) {
-        VisitForValue(prop->obj(), kStack);
-        VisitForValue(prop->key(), kAccumulator);
+        VisitForValue(property->obj(), kStack);
+        VisitForValue(property->key(), kAccumulator);
         __ movq(rdx, Operand(rsp, 0));
         __ push(rax);
       } else {
-        VisitForValue(prop->obj(), kStack);
-        VisitForValue(prop->key(), kStack);
+        VisitForValue(property->obj(), kStack);
+        VisitForValue(property->key(), kStack);
       }
       break;
   }
 
-  // If we have a compound assignment: Get value of LHS expression and
-  // store in on top of the stack.
   if (expr->is_compound()) {
     Location saved_location = location_;
-    location_ = kStack;
+    location_ = kAccumulator;
     switch (assign_type) {
       case VARIABLE:
         EmitVariableLoad(expr->target()->AsVariableProxy()->var(),
                          Expression::kValue);
         break;
       case NAMED_PROPERTY:
-        EmitNamedPropertyLoad(prop);
-        __ push(result_register());
+        EmitNamedPropertyLoad(property);
         break;
       case KEYED_PROPERTY:
-        EmitKeyedPropertyLoad(prop);
-        __ push(result_register());
+        EmitKeyedPropertyLoad(property);
         break;
     }
-    location_ = saved_location;
-  }
 
-  // Evaluate RHS expression.
-  Expression* rhs = expr->value();
-  VisitForValue(rhs, kAccumulator);
+    Token::Value op = expr->binary_op();
+    ConstantOperand constant = ShouldInlineSmiCase(op)
+        ? GetConstantOperand(op, expr->target(), expr->value())
+        : kNoConstants;
+    ASSERT(constant == kRightConstant || constant == kNoConstants);
+    if (constant == kNoConstants) {
+      __ push(rax);  // Left operand goes on the stack.
+      VisitForValue(expr->value(), kAccumulator);
+    }
 
-  // If we have a compound assignment: Apply operator.
-  if (expr->is_compound()) {
-    Location saved_location = location_;
-    location_ = kAccumulator;
     OverwriteMode mode = expr->value()->ResultOverwriteAllowed()
         ? OVERWRITE_RIGHT
         : NO_OVERWRITE;
-    EmitBinaryOp(expr->binary_op(), Expression::kValue, mode);
+    SetSourcePosition(expr->position() + 1);
+    if (ShouldInlineSmiCase(op)) {
+      EmitInlineSmiBinaryOp(expr,
+                            op,
+                            Expression::kValue,
+                            mode,
+                            expr->target(),
+                            expr->value(),
+                            constant);
+    } else {
+      EmitBinaryOp(op, Expression::kValue, mode);
+    }
     location_ = saved_location;
+
+  } else {
+    VisitForValue(expr->value(), kAccumulator);
   }
 
   // Record source position before possible IC call.
@@ -1264,6 +1282,74 @@ void FullCodeGenerator::EmitKeyedPropertyLoad(Property* prop) {
 }
 
 
+void FullCodeGenerator::EmitInlineSmiBinaryOp(Expression* expr,
+                                              Token::Value op,
+                                              Expression::Context context,
+                                              OverwriteMode mode,
+                                              Expression* left,
+                                              Expression* right,
+                                              ConstantOperand constant) {
+  ASSERT(constant == kNoConstants);  // Only handled case.
+
+  // Do combined smi check of the operands. Left operand is on the
+  // stack (popped into rdx). Right operand is in rax but moved into
+  // rcx to make the shifts easier.
+  Label done, stub_call, smi_case;
+  __ pop(rdx);
+  __ movq(rcx, rax);
+  Condition smi = __ CheckBothSmi(rdx, rax);
+  __ j(smi, &smi_case);
+
+  __ bind(&stub_call);
+  GenericBinaryOpStub stub(op, mode, NO_SMI_CODE_IN_STUB, TypeInfo::Unknown());
+  if (stub.ArgsInRegistersSupported()) {
+    stub.GenerateCall(masm_, rdx, rcx);
+  } else {
+    __ push(rdx);
+    __ push(rcx);
+    __ CallStub(&stub);
+  }
+  __ jmp(&done);
+
+  __ bind(&smi_case);
+  switch (op) {
+    case Token::SAR:
+      __ SmiShiftArithmeticRight(rax, rdx, rcx);
+      break;
+    case Token::SHL:
+      __ SmiShiftLeft(rax, rdx, rcx);
+      break;
+    case Token::SHR:
+      __ SmiShiftLogicalRight(rax, rdx, rcx, &stub_call);
+      break;
+    case Token::ADD:
+      __ SmiAdd(rax, rdx, rcx, &stub_call);
+      break;
+    case Token::SUB:
+      __ SmiSub(rax, rdx, rcx, &stub_call);
+      break;
+    case Token::MUL:
+      __ SmiMul(rax, rdx, rcx, &stub_call);
+      break;
+    case Token::BIT_OR:
+      __ SmiOr(rax, rdx, rcx);
+      break;
+    case Token::BIT_AND:
+      __ SmiAnd(rax, rdx, rcx);
+      break;
+    case Token::BIT_XOR:
+      __ SmiXor(rax, rdx, rcx);
+      break;
+    default:
+      UNREACHABLE();
+      break;
+  }
+
+  __ bind(&done);
+  Apply(context, rax);
+}
+
+
 void FullCodeGenerator::EmitBinaryOp(Token::Value op,
                                      Expression::Context context,
                                      OverwriteMode mode) {
@@ -1971,8 +2057,8 @@ void FullCodeGenerator::EmitObjectEquals(ZoneList<Expression*>* args) {
 void FullCodeGenerator::EmitArguments(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 1);
 
-  // ArgumentsAccessStub expects the key in edx and the formal
-  // parameter count in eax.
+  // ArgumentsAccessStub expects the key in rdx and the formal
+  // parameter count in rax.
   VisitForValue(args->at(0), kAccumulator);
   __ movq(rdx, rax);
   __ Move(rax, Smi::FromInt(scope()->num_parameters()));
@@ -2176,7 +2262,7 @@ void FullCodeGenerator::EmitSetValueOf(ZoneList<Expression*>* args) {
 
   VisitForValue(args->at(0), kStack);  // Load the object.
   VisitForValue(args->at(1), kAccumulator);  // Load the value.
-  __ pop(rbx);  // rax = value. ebx = object.
+  __ pop(rbx);  // rax = value. rbx = object.
 
   Label done;
   // If the object is a smi, return the value.