[turbofan] Various fixes to allow unboxed doubles as arguments in registers and on the stack.

src/compiler/x64/code-generator-x64.cc

 // Copyright 2013 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/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/scopes.h"
@@ skipping 1201 matching lines @@
       break;
     case kX64Inc32:
       __ incl(i.OutputRegister());
       break;
     case kX64Push:
       if (HasImmediateInput(instr, 0)) {
         __ pushq(i.InputImmediate(0));
       } else {
         if (instr->InputAt(0)->IsRegister()) {
           __ pushq(i.InputRegister(0));
+        } else if (instr->InputAt(0)->IsDoubleRegister()) {
+          // TODO(titzer): use another machine instruction?
+          __ subq(rsp, Immediate(8));

[Jarin, 2015/08/03 10:38:18]

Maybe replace 8 with kDoubleSize?

+          __ movsd(Operand(rsp, 0), i.InputDoubleRegister(0));
         } else {
           __ pushq(i.InputOperand(0));
         }
       }
       break;
     case kX64Poke: {
       int const slot = MiscField::decode(instr->opcode());
       if (HasImmediateInput(instr, 0)) {
         __ movq(Operand(rsp, slot * kPointerSize), i.InputImmediate(0));
       } else {
@@ skipping 315 matching lines @@
         __ addp(rsp, Immediate(stack_size));
       }
       const RegList saves = descriptor->CalleeSavedRegisters();
       if (saves != 0) {
         for (int i = 0; i < Register::kNumRegisters; i++) {
           if (!((1 << i) & saves)) continue;
           __ popq(Register::from_code(i));
         }
       }
       __ popq(rbp);  // Pop caller's frame pointer.
-      __ ret(0);
     } else {
       // No saved registers.
       __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
       __ popq(rbp);       // Pop caller's frame pointer.
-      __ ret(0);
     }
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
     // Canonicalize JSFunction return sites for now.
     if (return_label_.is_bound()) {
       __ jmp(&return_label_);
+      return;
     } else {
       __ bind(&return_label_);
       __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
       __ popq(rbp);       // Pop caller's frame pointer.
-      int pop_count = static_cast<int>(descriptor->StackParameterCount());
-      if (pop_count == 0) {
-        __ Ret();
-      } else {
-        __ Ret(pop_count * kPointerSize, rbx);
-      }
     }
-  } else {
-    __ Ret();
   }
+  size_t pop_size = descriptor->StackParameterCount() * kPointerSize;
+  // Might need rcx for scratch if pop_size is too big.
+  DCHECK_EQ(0, descriptor->CalleeSavedRegisters() & rcx.bit());
+  __ Ret(static_cast<int>(pop_size), rcx);
 }
 
 
 void CodeGenerator::AssembleMove(InstructionOperand* source,
                                  InstructionOperand* destination) {
   X64OperandConverter g(this, NULL);
   // Dispatch on the source and destination operand kinds.  Not all
   // combinations are possible.
   if (source->IsRegister()) {
     DCHECK(destination->IsRegister() || destination->IsStackSlot());
@@ skipping 177 matching lines @@
       __ Nop(padding_size);
     }
   }
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace compiler
 }  // namespace v8