Add support for long-to-double in the optimizing compiler.

- Add support for the long-to-double Dex instruction in the
  optimizing compiler.
- Enable requests of temporary FPU (double) registers during
  code generation.
- Fix art::x86::X86Assembler::LoadLongConstant and extend
  it to int64_t values.
- Have art::x86_64::X86_64Assembler::cvtsi2sd work with
  64-bit operands.
- Generate x86, x86-64 and ARM (but not ARM64) code for
  long to double HTypeConversion nodes.
- Add related tests to test/422-type-conversion.

Change-Id: Ie73d9e5e25bd2e15f585c371e8fc2dcb83438ccd
diff --git a/compiler/utils/x86_64/assembler_x86_64.h b/compiler/utils/x86_64/assembler_x86_64.h
index ab1bc9e..9f31818 100644
--- a/compiler/utils/x86_64/assembler_x86_64.h
+++ b/compiler/utils/x86_64/assembler_x86_64.h
@@ -330,6 +330,7 @@
 
   void cvtsi2ss(XmmRegister dst, CpuRegister src);  // Note: this is the r/m32 version.
   void cvtsi2sd(XmmRegister dst, CpuRegister src);  // Note: this is the r/m32 version.
+  void cvtsi2sd(XmmRegister dst, CpuRegister src, bool is64bit);
 
   void cvtss2si(CpuRegister dst, XmmRegister src);  // Note: this is the r32 version.
   void cvtss2sd(XmmRegister dst, XmmRegister src);