Karl Magdsick wrote: [snip] > With proper support from the compiler, it's theoretically possible on > x86-64 systems to use 32-bit pointers in long mode (16 general purpose > 64-bit registers). (There's an instruction prefix that will cause the > CPU to perform 32-bit pointer calculations in the 64-bit address > space.) I'm not aware of any systems that use this, however. (Getting > the speed boost from fewer register spills while not paying the space > cost of 64-bit pointers sounds very attractive in many applications, > though.)
FYI, the MIPS N32 ABI does that (64bit wide registers, 32bit address space, data type sizes compatible to pure 32bit programs). Thiemo
