[turbofan] Fix stack->stack double moves for pushing on ia32 and x64.

src/compiler/x64/instruction-selector-x64.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 <algorithm>
 
 #include "src/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
@@ skipping 1036 matching lines @@
 
   // Prepare for C function call.
   if (descriptor->IsCFunctionCall()) {
     Emit(kArchPrepareCallCFunction |
              MiscField::encode(static_cast<int>(descriptor->CParameterCount())),
          0, nullptr, 0, nullptr);
 
     // Poke any stack arguments.
     for (size_t n = 0; n < buffer.pushed_nodes.size(); ++n) {
       if (Node* input = buffer.pushed_nodes[n]) {
-        int const slot = static_cast<int>(n);
+        int slot = static_cast<int>(n);
         InstructionOperand value = g.CanBeImmediate(input)
                                        ? g.UseImmediate(input)
                                        : g.UseRegister(input);
         Emit(kX64Poke | MiscField::encode(slot), g.NoOutput(), value);
       }
     }
   } else {
     // Push any stack arguments.
     for (Node* input : base::Reversed(buffer.pushed_nodes)) {
-      // TODO(titzer): handle pushing double parameters.
+      // TODO(titzer): X64Push cannot handle stack->stack double moves
+      // because there is no way to encode fixed double slots.
       InstructionOperand value =
           g.CanBeImmediate(input)
               ? g.UseImmediate(input)
-              : IsSupported(ATOM) ? g.UseRegister(input) : g.Use(input);
+              : IsSupported(ATOM) ||
+                        sequence()->IsFloat(GetVirtualRegister(input))
+                    ? g.UseRegister(input)
+                    : g.Use(input);
       Emit(kX64Push, g.NoOutput(), value);
     }
   }
 
   // Pass label of exception handler block.
   CallDescriptor::Flags flags = descriptor->flags();
   if (handler) {
     DCHECK_EQ(IrOpcode::kIfException, handler->front()->opcode());
     IfExceptionHint hint = OpParameter<IfExceptionHint>(handler->front());
     if (hint == IfExceptionHint::kLocallyCaught) {
@@ skipping 592 matching lines @@
   if (CpuFeatures::IsSupported(SSE4_1)) {
     flags |= MachineOperatorBuilder::kFloat64RoundDown |
              MachineOperatorBuilder::kFloat64RoundTruncate;
   }
   return flags;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8