Adding support for multiple returns in compiled functions.

src/compiler/instruction-selector.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.h"
 
 #include <limits>
 
 #include "src/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
@@ skipping 486 matching lines @@
       DCHECK_LE(sw.min_value, sw.max_value);
       // Note that {value_range} can be 0 if {min_value} is -2^31 and
       // {max_value}
       // is 2^31-1, so don't assume that it's non-zero below.
       sw.value_range = 1u + bit_cast<uint32_t>(sw.max_value) -
                        bit_cast<uint32_t>(sw.min_value);
       return VisitSwitch(input, sw);
     }
     case BasicBlock::kReturn: {
       DCHECK_EQ(IrOpcode::kReturn, input->opcode());
-      return VisitReturn(input->InputAt(0));
+      return VisitReturn(input);
     }
     case BasicBlock::kDeoptimize: {
       // If the result itself is a return, return its input.
       Node* value =
           (input != nullptr && input->opcode() == IrOpcode::kDeoptimize)
               ? input->InputAt(0)
               : input;
       return VisitDeoptimize(value);
     }
     case BasicBlock::kThrow:
@@ skipping 484 matching lines @@
 }
 
 
 void InstructionSelector::VisitGoto(BasicBlock* target) {
   // jump to the next block.
   OperandGenerator g(this);
   Emit(kArchJmp, g.NoOutput(), g.Label(target));
 }
 
 
-void InstructionSelector::VisitReturn(Node* value) {
-  DCHECK_NOT_NULL(value);
+void InstructionSelector::VisitReturn(Node* input) {
   OperandGenerator g(this);
   if (linkage()->GetIncomingDescriptor()->ReturnCount() == 0) {
     Emit(kArchRet, g.NoOutput());
   } else {
-    Emit(kArchRet, g.NoOutput(),
-         g.UseLocation(value, linkage()->GetReturnLocation(),
-                       linkage()->GetReturnType()));
+    const int input_count = input->op()->ValueInputCount();
+    auto value_locations = zone()->NewArray<InstructionOperand>(input_count);
+    for (int i = 0; i < input_count; ++i) {
+      DCHECK_NOT_NULL(input->InputAt(i));
+      value_locations[i] =
+          g.UseLocation(input->InputAt(i), linkage()->GetReturnLocation(i),
+                        linkage()->GetReturnType());

[titzer, 2015/10/07 23:57:05]

GetReturnType(i) ?

[bradn, 2015/10/08 17:13:37]

Done.

+    }
+    Emit(kArchRet, 0, nullptr, input_count, value_locations);
   }
 }
 
 
 void InstructionSelector::VisitDeoptimize(Node* value) {
   OperandGenerator g(this);
 
   FrameStateDescriptor* desc = GetFrameStateDescriptor(value);
   size_t arg_count = desc->GetTotalSize() + 1;  // Include deopt id.
 
@@ skipping 113 matching lines @@
   for (StateValuesAccess::TypedNode input_node : StateValuesAccess(stack)) {
     inputs->push_back(OperandForDeopt(&g, input_node.node, kind));
     descriptor->SetType(value_index++, input_node.type);
   }
   DCHECK(value_index == descriptor->GetSize());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8