x86 - x64 porting query

1
votes

We have an application written in C/C++ code running on 32-bits windows with 32-bit Hardware. My question is that if we upgrade our hardware to 64-bit and keep our OS 32-bit, does my application need a port to 64-bit? If it requires, what benefits will be there on a 32 bit OS?

2
windowsx8664-bit32bit-64bitporting
You already have 64-bit hardware. Nearly every CPU sold in the past 8 years or so is 64-bit capable (with the exceptions of a few Atoms). - Helge Klein

2 Answers

5
votes

Hardware doesn't count -- the OS does. Ergo:

  • 32 bit hardware with 32 bit OS will run only 32 bit ports
  • 64 bit hardware with 32 bit OS will run only 32 bit ports
  • 64 bit hardware with 64 bit OS will run both 32 bit and 64 bit ports

The advantage of recompiling for 64 bit is access to more than 3GB ram and a speed increase if you operate on 64 bit datatypes or take advantage of compiler intristics (and a few others, but do not count on a immedate gain).

0
votes

If you keep the OS 32-bit, you must keep the app 32-bit, for many common values of OS. We, of course, cannot use telepathy to tell which OS you are using.