[turbofan] Support for combining branches with <Operation>WithOverflow.

src/compiler/ia32/instruction-selector-ia32.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties-inl.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 143 matching lines @@
   } else {  // store [%base + %index], %|#value
     Emit(opcode | AddressingModeField::encode(kMode_MR1I), NULL,
          g.UseRegister(base), g.UseRegister(index), val);
   }
   // TODO(turbofan): addressing modes [r+r*{2,4,8}+K]
 }
 
 
 // Shared routine for multiple binary operations.
 static void VisitBinop(InstructionSelector* selector, Node* node,
-                       ArchOpcode opcode) {
+                       InstructionCode opcode, FlagsContinuation* cont) {
   IA32OperandGenerator g(selector);
   Int32BinopMatcher m(node);
-  // TODO(turbofan): match complex addressing modes.
-  // TODO(turbofan): if commutative, pick the non-live-in operand as the left as
-  // this might be the last use and therefore its register can be reused.
-  if (g.CanBeImmediate(m.right().node())) {
-    selector->Emit(opcode, g.DefineSameAsFirst(node), g.Use(m.left().node()),
-                   g.UseImmediate(m.right().node()));
-  } else {
-    selector->Emit(opcode, g.DefineSameAsFirst(node),
-                   g.UseRegister(m.left().node()), g.Use(m.right().node()));
-  }
-}
-
-
-static void VisitBinopWithOverflow(InstructionSelector* selector, Node* node,
-                                   InstructionCode opcode) {
-  IA32OperandGenerator g(selector);
-  Int32BinopMatcher m(node);
-  InstructionOperand* inputs[2];
+  InstructionOperand* inputs[4];
   size_t input_count = 0;
   InstructionOperand* outputs[2];
   size_t output_count = 0;
 
   // TODO(turbofan): match complex addressing modes.
   // TODO(turbofan): if commutative, pick the non-live-in operand as the left as
   // this might be the last use and therefore its register can be reused.
   if (g.CanBeImmediate(m.right().node())) {
     inputs[input_count++] = g.Use(m.left().node());
     inputs[input_count++] = g.UseImmediate(m.right().node());
   } else {
     inputs[input_count++] = g.UseRegister(m.left().node());
     inputs[input_count++] = g.Use(m.right().node());
   }
 
-  // Define outputs depending on the projections.
-  Node* projections[2];
-  node->CollectProjections(ARRAY_SIZE(projections), projections);
-  if (projections[0]) {
-    outputs[output_count++] = g.DefineSameAsFirst(projections[0]);
+  if (cont->IsBranch()) {
+    inputs[input_count++] = g.Label(cont->true_block());
+    inputs[input_count++] = g.Label(cont->false_block());
   }
-  if (projections[1]) {
-    opcode |= FlagsModeField::encode(kFlags_set);
-    opcode |= FlagsConditionField::encode(kOverflow);
+
+  outputs[output_count++] = g.DefineSameAsFirst(node);
+  if (cont->IsSet()) {
     // TODO(turbofan): Use byte register here.
-    outputs[output_count++] =
-        (projections[0] ? g.DefineAsRegister(projections[1])
-                        : g.DefineSameAsFirst(projections[1]));
+    outputs[output_count++] = g.DefineAsRegister(cont->result());
   }
 
   ASSERT_NE(0, input_count);
   ASSERT_NE(0, output_count);
   ASSERT_GE(ARRAY_SIZE(inputs), input_count);
   ASSERT_GE(ARRAY_SIZE(outputs), output_count);
 
-  selector->Emit(opcode, output_count, outputs, input_count, inputs);
+  Instruction* instr = selector->Emit(cont->Encode(opcode), output_count,
+                                      outputs, input_count, inputs);
+  if (cont->IsBranch()) instr->MarkAsControl();
 }
 
 
+// Shared routine for multiple binary operations.
+static void VisitBinop(InstructionSelector* selector, Node* node,
+                       InstructionCode opcode) {
+  FlagsContinuation cont;
+  VisitBinop(selector, node, opcode, &cont);
+}
+
+
 void InstructionSelector::VisitWord32And(Node* node) {
   VisitBinop(this, node, kIA32And);
 }
 
 
 void InstructionSelector::VisitWord32Or(Node* node) {
   VisitBinop(this, node, kIA32Or);
 }
 
 
@@ skipping 46 matching lines @@
 void InstructionSelector::VisitWord32Sar(Node* node) {
   VisitShift(this, node, kIA32Sar);
 }
 
 
 void InstructionSelector::VisitInt32Add(Node* node) {
   VisitBinop(this, node, kIA32Add);
 }
 
 
-void InstructionSelector::VisitInt32AddWithOverflow(Node* node) {
-  VisitBinopWithOverflow(this, node, kIA32Add);
-}
-
-
 void InstructionSelector::VisitInt32Sub(Node* node) {
   IA32OperandGenerator g(this);
   Int32BinopMatcher m(node);
   if (m.left().Is(0)) {
     Emit(kIA32Neg, g.DefineSameAsFirst(node), g.Use(m.right().node()));
   } else {
     VisitBinop(this, node, kIA32Sub);
   }
 }
 
 
-void InstructionSelector::VisitInt32SubWithOverflow(Node* node) {
-  VisitBinopWithOverflow(this, node, kIA32Sub);
-}
-
-
 void InstructionSelector::VisitInt32Mul(Node* node) {
   IA32OperandGenerator g(this);
   Node* left = node->InputAt(0);
   Node* right = node->InputAt(1);
   if (g.CanBeImmediate(right)) {
     Emit(kIA32Imul, g.DefineAsRegister(node), g.Use(left),
          g.UseImmediate(right));
   } else if (g.CanBeImmediate(left)) {
     Emit(kIA32Imul, g.DefineAsRegister(node), g.Use(right),
          g.UseImmediate(left));
@@ skipping 110 matching lines @@
 
 void InstructionSelector::VisitFloat64Mod(Node* node) {
   IA32OperandGenerator g(this);
   InstructionOperand* temps[] = {g.TempRegister(eax)};
   Emit(kSSEFloat64Mod, g.DefineSameAsFirst(node),
        g.UseDoubleRegister(node->InputAt(0)),
        g.UseDoubleRegister(node->InputAt(1)), 1, temps);
 }
 
 
+void InstructionSelector::VisitInt32AddWithOverflow(Node* node,
+                                                    FlagsContinuation* cont) {
+  VisitBinop(this, node, kIA32Add, cont);
+}
+
+
+void InstructionSelector::VisitInt32SubWithOverflow(Node* node,
+                                                    FlagsContinuation* cont) {
+  VisitBinop(this, node, kIA32Sub, cont);
+}
+
+
 // Shared routine for multiple compare operations.
 static inline void VisitCompare(InstructionSelector* selector,
                                 InstructionCode opcode,
                                 InstructionOperand* left,
                                 InstructionOperand* right,
                                 FlagsContinuation* cont) {
   IA32OperandGenerator g(selector);
   if (cont->IsBranch()) {
     selector->Emit(cont->Encode(opcode), NULL, left, right,
                    g.Label(cont->true_block()),
@@ skipping 109 matching lines @@
   if (descriptor->kind() == CallDescriptor::kCallAddress &&
       buffer.pushed_count > 0) {
     ASSERT(deoptimization == NULL && continuation == NULL);
     Emit(kPopStack | MiscField::encode(buffer.pushed_count), NULL);
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8