Prepare for optionally inlining smi cases in the code generated

by the full codegens.
Review URL: http://codereview.chromium.org/3116042

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5343 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/full-codegen-arm.cc

@@ -665,10 +665,10 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
     // Compile the label expression.
     VisitForValue(clause->label(), kAccumulator);
 
-    // Perform the comparison as if via '==='.  The comparison stub expects
-    // the smi vs. smi case to be handled before it is called.
-    Label slow_case;
+    // Perform the comparison as if via '==='.
     __ ldr(r1, MemOperand(sp, 0));  // Switch value.
+    if (ShouldInlineSmiCase(Token::EQ_STRICT)) {
+      Label slow_case;
       __ orr(r2, r1, r0);
       __ tst(r2, Operand(kSmiTagMask));
       __ b(ne, &slow_case);
@@ -676,8 +676,9 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
       __ b(ne, &next_test);
       __ Drop(1);  // Switch value is no longer needed.
       __ b(clause->body_target()->entry_label());
-
     __ bind(&slow_case);
+    }
+
     CompareStub stub(eq, true, kBothCouldBeNaN, true, r1, r0);
     __ CallStub(&stub);
     __ cmp(r0, Operand(0));
@@ -2672,26 +2673,26 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
 
     case Token::BIT_NOT: {
       Comment cmt(masm_, "[ UnaryOperation (BIT_NOT)");
-      bool can_overwrite = expr->expression()->ResultOverwriteAllowed();
-      UnaryOverwriteMode overwrite =
-          can_overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
-      GenericUnaryOpStub stub(Token::BIT_NOT, overwrite);
-      // GenericUnaryOpStub expects the argument to be in the
-      // accumulator register r0.
+      // The generic unary operation stub expects the argument to be
+      // in the accumulator register r0.
       VisitForValue(expr->expression(), kAccumulator);
-      // Avoid calling the stub for Smis.
-      Label smi, done;
-      __ BranchOnSmi(result_register(), &smi);
-      // Non-smi: call stub leaving result in accumulator register.
-      __ CallStub(&stub);
-      __ b(&done);
-      // Perform operation directly on Smis.
-      __ bind(&smi);
-      __ mvn(result_register(), Operand(result_register()));
+      Label done;
+      if (ShouldInlineSmiCase(expr->op())) {
+        Label call_stub;
+        __ BranchOnNotSmi(r0, &call_stub);
+        __ mvn(r0, Operand(r0));
         // Bit-clear inverted smi-tag.
-      __ bic(result_register(), result_register(), Operand(kSmiTagMask));
+        __ bic(r0, r0, Operand(kSmiTagMask));
+        __ b(&done);
+        __ bind(&call_stub);
+      }
+      bool overwrite = expr->expression()->ResultOverwriteAllowed();
+      UnaryOverwriteMode mode =
+          overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
+      GenericUnaryOpStub stub(Token::BIT_NOT, mode);
+      __ CallStub(&stub);
       __ bind(&done);
-      Apply(context_, result_register());
+      Apply(context_, r0);
       break;
     }
 
@@ -3055,16 +3056,15 @@ void FullCodeGenerator::VisitCompareOperation(CompareOperation* expr) {
           UNREACHABLE();
       }
 
-      // The comparison stub expects the smi vs. smi case to be handled
-      // before it is called.
+      if (ShouldInlineSmiCase(op)) {
         Label slow_case;
         __ orr(r2, r0, Operand(r1));
         __ BranchOnNotSmi(r2, &slow_case);
         __ cmp(r1, r0);
-      __ b(cc, if_true);
-      __ jmp(if_false);
-
+        Split(cc, if_true, if_false, NULL);
         __ bind(&slow_case);
+      }
+
       CompareStub stub(cc, strict, kBothCouldBeNaN, true, r1, r0);
       __ CallStub(&stub);
       __ cmp(r0, Operand(0));

src/full-codegen.cc

@@ -318,9 +318,15 @@ int FullCodeGenerator::SlotOffset(Slot* slot) {
 
 
 bool FullCodeGenerator::ShouldInlineSmiCase(Token::Value op) {
-  if (Debugger::IsDebuggerActive()) return false;
-  if (op == Token::DIV ||op == Token::MOD) return false;
-  return loop_depth_ > 0;
+  // TODO(kasperl): Once the compare stub allows leaving out the
+  // inlined smi case, we should get rid of this check.
+  if (Token::IsCompareOp(op)) return true;
+  // TODO(kasperl): Once the unary bit not stub allows leaving out
+  // the inlined smi case, we should get rid of this check.
+  if (op == Token::BIT_NOT) return true;
+  // Inline smi case inside loops, but not division and modulo which
+  // are too complicated and take up too much space.
+  return (op != Token::DIV) && (op != Token::MOD) && (loop_depth_ > 0);
 }
 
 

src/ia32/full-codegen-ia32.cc

@@ -668,10 +668,10 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
     // Compile the label expression.
     VisitForValue(clause->label(), kAccumulator);
 
-    // Perform the comparison as if via '==='.  The comparison stub expects
-    // the smi vs. smi case to be handled before it is called.
-    Label slow_case;
+    // Perform the comparison as if via '==='.
     __ mov(edx, Operand(esp, 0));  // Switch value.
+    if (ShouldInlineSmiCase(Token::EQ_STRICT)) {
+      Label slow_case;
       __ mov(ecx, edx);
       __ or_(ecx, Operand(eax));
       __ test(ecx, Immediate(kSmiTagMask));
@@ -680,8 +680,9 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
       __ j(not_equal, &next_test);
       __ Drop(1);  // Switch value is no longer needed.
       __ jmp(clause->body_target()->entry_label());
-
       __ bind(&slow_case);
+    }
+
     CompareStub stub(equal, true);
     __ CallStub(&stub);
     __ test(eax, Operand(eax));
@@ -2672,26 +2673,26 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
 
     case Token::BIT_NOT: {
       Comment cmt(masm_, "[ UnaryOperation (BIT_NOT)");
-      bool can_overwrite = expr->expression()->ResultOverwriteAllowed();
-      UnaryOverwriteMode overwrite =
-          can_overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
-      GenericUnaryOpStub stub(Token::BIT_NOT, overwrite);
-      // GenericUnaryOpStub expects the argument to be in the
-      // accumulator register eax.
+      // The generic unary operation stub expects the argument to be
+      // in the accumulator register eax.
       VisitForValue(expr->expression(), kAccumulator);
-      // Avoid calling the stub for Smis.
-      Label smi, done;
-      __ test(result_register(), Immediate(kSmiTagMask));
-      __ j(zero, &smi);
-      // Non-smi: call stub leaving result in accumulator register.
-      __ CallStub(&stub);
+      Label done;
+      if (ShouldInlineSmiCase(expr->op())) {
+        Label call_stub;
+        __ test(eax, Immediate(kSmiTagMask));
+        __ j(not_zero, &call_stub);
+        __ lea(eax, Operand(eax, kSmiTagMask));
+        __ not_(eax);
         __ jmp(&done);
-      // Perform operation directly on Smis.
-      __ bind(&smi);
-      __ not_(result_register());
-      __ and_(result_register(), ~kSmiTagMask);  // Remove inverted smi-tag.
+        __ bind(&call_stub);
+      }
+      bool overwrite = expr->expression()->ResultOverwriteAllowed();
+      UnaryOverwriteMode mode =
+          overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
+      GenericUnaryOpStub stub(Token::BIT_NOT, mode);
+      __ CallStub(&stub);
       __ bind(&done);
-      Apply(context_, result_register());
+      Apply(context_, eax);
       break;
     }
 
@@ -3066,18 +3067,17 @@ void FullCodeGenerator::VisitCompareOperation(CompareOperation* expr) {
           UNREACHABLE();
       }
 
-      // The comparison stub expects the smi vs. smi case to be
-      // handled before it is called.
+      if (ShouldInlineSmiCase(op)) {
         Label slow_case;
         __ mov(ecx, Operand(edx));
         __ or_(ecx, Operand(eax));
         __ test(ecx, Immediate(kSmiTagMask));
         __ j(not_zero, &slow_case, not_taken);
         __ cmp(edx, Operand(eax));
-      __ j(cc, if_true);
-      __ jmp(if_false);
-
+        Split(cc, if_true, if_false, NULL);
         __ bind(&slow_case);
+      }
+
       CompareStub stub(cc, strict);
       __ CallStub(&stub);
       __ test(eax, Operand(eax));

src/x64/full-codegen-x64.cc

@@ -672,8 +672,8 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
     // Compile the label expression.
     VisitForValue(clause->label(), kAccumulator);
 
-    // Perform the comparison as if via '==='.  The comparison stub expects
-    // the smi vs. smi case to be handled before it is called.
+    // Perform the comparison as if via '==='.
+    if (ShouldInlineSmiCase(Token::EQ_STRICT)) {
       Label slow_case;
       __ movq(rdx, Operand(rsp, 0));  // Switch value.
       __ JumpIfNotBothSmi(rdx, rax, &slow_case);
@@ -681,8 +681,9 @@ void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
       __ j(not_equal, &next_test);
       __ Drop(1);  // Switch value is no longer needed.
       __ jmp(clause->body_target()->entry_label());
-
       __ bind(&slow_case);
+    }
+
     CompareStub stub(equal, true);
     __ CallStub(&stub);
     __ testq(rax, rax);
@@ -2667,25 +2668,24 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
 
     case Token::BIT_NOT: {
       Comment cmt(masm_, "[ UnaryOperation (BIT_NOT)");
-      bool can_overwrite = expr->expression()->ResultOverwriteAllowed();
-      UnaryOverwriteMode overwrite =
-          can_overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
-      GenericUnaryOpStub stub(Token::BIT_NOT, overwrite);
-      // GenericUnaryOpStub expects the argument to be in the
-      // accumulator register rax.
+      // The generic unary operation stub expects the argument to be
+      // in the accumulator register rax.
       VisitForValue(expr->expression(), kAccumulator);
-      // Avoid calling the stub for Smis.
-      Label smi, done;
-      Condition is_smi = masm_->CheckSmi(result_register());
-      __ j(is_smi, &smi);
-      // Non-smi: call stub leaving result in accumulator register.
-      __ CallStub(&stub);
+      Label done;
+      if (ShouldInlineSmiCase(expr->op())) {
+        Label call_stub;
+        __ JumpIfNotSmi(rax, &call_stub);
+        __ SmiNot(rax, rax);
         __ jmp(&done);
-      // Perform operation directly on Smis.
-      __ bind(&smi);
-      __ SmiNot(result_register(), result_register());
+        __ bind(&call_stub);
+      }
+      bool overwrite = expr->expression()->ResultOverwriteAllowed();
+      UnaryOverwriteMode mode =
+          overwrite ? UNARY_OVERWRITE : UNARY_NO_OVERWRITE;
+      GenericUnaryOpStub stub(Token::BIT_NOT, mode);
+      __ CallStub(&stub);
       __ bind(&done);
-      Apply(context_, result_register());
+      Apply(context_, rax);
       break;
     }
 
@@ -3054,15 +3054,14 @@ void FullCodeGenerator::VisitCompareOperation(CompareOperation* expr) {
           UNREACHABLE();
       }
 
-      // The comparison stub expects the smi vs. smi case to be handled
-      // before it is called.
+      if (ShouldInlineSmiCase(op)) {
         Label slow_case;
         __ JumpIfNotBothSmi(rax, rdx, &slow_case);
         __ SmiCompare(rdx, rax);
-      __ j(cc, if_true);
-      __ jmp(if_false);
-
+        Split(cc, if_true, if_false, NULL);
         __ bind(&slow_case);
+      }
+
       CompareStub stub(cc, strict);
       __ CallStub(&stub);
       __ testq(rax, rax);