On 04/01/2010 10:54 PM, Daniel Jacobowitz wrote:
> I'm debugging a Thumb-2 glibc build failure on trunk for
> arm-none-linux-gnueabi. I believe it's from Richard Earnshaw's
> 2010-02-01 patch for TLS patterns, which includes this:
>
> (define_insn "tls_load_dot_plus_four"
> [(set (match_operand:SI 0 "register_operand" "=l,r")
> (mem:SI (unspec:SI [(match_operand:SI 1 "register_operand" "+l,r")
> (const_int 4)
> (match_operand 2 "" "")]
> UNSPEC_PIC_BASE)))]
>
> It's that "+" on the second operand. It should just be "&", and I
> think that will fix the failure (I'll test it shortly).
That can't be right, "&" only makes sense for outputs.
[...]
> It seems to me that the problem is marking a register in the RHS of a
> set as an output constraint.
Yes. There was a similar bug for tls_load_dot_plus_eight recently. In
this case it seems that operand 1 is in fact both read and written by
the pattern, so the pattern should be something like
[(set (match_operand:SI 0 "register_operand" "=l,r")
(mem:SI (unspec:SI [(match_dup 1)
(const_int 4)
(match_operand 2 "" "")]
UNSPEC_PIC_BASE)))
(clobber (match_operand:SI 1 "register_operand" "+&l,&r"))]
That's untested however.
Bernd
