search for: __put_user_

...in the same register, then they have to be in the same register. >> > > Sounds logical! But what is the discussion about then? LLVM's Codegen is rejecting inline asm when input/output constraints have different bitwidths. For example in the Linux kernel calls to the various __put_user_ functions take %al, %ax, %eax, %rax/ (%eax:%edx) as input parameter, and the output parameter is always an int (%eax). (hope I explained this right) But if I got it right, the input can also be a struct (who's size is 1, 2, 4, 8-byte) that fits in a register. Not sure if this ever occurs in pr...

On Tuesday 27 January 2009 20:56:30 Mike Stump wrote: > On Jan 27, 2009, at 8:42 PM, Duncan Sands wrote: > > one thing that seems to be clear to everyone except me is... what > > are the > > semantics supposed to be? > > I don't know of any other semantic other than, if they are supposed to > be in the same register, then they have to be in the same register.

...ey have to be in the same register. >>> >> >> Sounds logical! But what is the discussion about then? > > LLVM's Codegen is rejecting inline asm when input/output constraints > have different bitwidths. > > For example in the Linux kernel calls to the various __put_user_ > functions take %al, %ax, %eax, %rax/ (%eax:%edx) as input parameter, > and the output parameter is always an int (%eax). (hope I explained > this > right) Right, the interesting wrinkle is that I think llvm's codegen should only see matching constraints of the same type. If...

Hi Chris, > > LLVM's Codegen is rejecting inline asm when input/output constraints > > have different bitwidths. > > > > For example in the Linux kernel calls to the various __put_user_ > > functions take %al, %ax, %eax, %rax/ (%eax:%edx) as input parameter, > > and the output parameter is always an int (%eax). (hope I explained > > this > > right) > > Right, the interesting wrinkle is that I think llvm's codegen should > only see matching...