On Wed, 5 Dec 2001, John Baldwin wrote:

Review of what I can see and quote easily.

> The patch is at http://www.FreeBSD.org/~jhb/patches/i386_asm.patch.  Mostly it
> does the following:

This URL appears to be well formed ;-).

> - Add missing "cc" clobbers in constraints

Does this have any effect (for i386's) except to create a lot of clutter
Even i386.md doesn't use it.  gcc.info says:

!    If your assembler instruction can alter the condition code register,
! add `cc' to the list of clobbered registers.  GNU CC on some machines
! represents the condition codes as a specific hardware register; `cc'
! serves to name this register.  On other machines, the condition code is
! handled differently, and specifying `cc' has no effect.  But it is
! valid no matter what the machine.
! ...
!    Here we will concern ourselves with determining the effect of an
! insn on the condition code and will limit ourselves to the following
! possible effects:  The condition code can be set unpredictably
! (clobbered), not be changed, be set to agree with the results of the
! operation, or only changed if the item previously set into the
! condition code has been modified.
!    Here is part of a sample `md' file for such a machine:
!      (define_attr "type" "load,store,arith,fp,branch" (const_string "arith"))
!      (define_attr "cc" "clobber,unchanged,set,change0"

None of i386.md, alpha.md or sparc.md do this.  i386's and alphas have a
cc0 register, but it is only mentioned for instructsions whose main (only?)
effect is to to set the condition codes.

> - Use the "+" modifier for output operands rather than using "0", "1", etc.
>   to list operands in both input and output sections.
> - Fix the atomic operations to accept the contraints type on v so we can use
>   "iq" rather than "ir" for char operations (this last came from Peter Jeremy
>   and bde).



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