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Re: [new-regalloc-branch]: Fix bunch of thinkos, stop useless spilling


On Fri, Jul 27, 2001 at 11:38:09PM -0400, Daniel Berlin wrote:
> Code in propagate_one_insn like, fer instance,  :
> 
>   /* If this is not the final pass, and this insn is copying the value of
>      a library call and it's dead, don't scan the insns that perform the
>      library call, so that the call's arguments are not marked live.  */
>   if (libcall_is_dead)
>     {
>       /* Record the death of the dest reg.  */
>       mark_set_regs (pbi, PATTERN (insn), insn);
> 
>       insn = XEXP (note, 0);
>       return PREV_INSN (insn);
>     }
> 
> will jump to the first argument set, which in a case above, would be
> already before the bb->head we are looking for to end the loop, and we
> screw up as i said above.

That's already wrong.  A libcall _must_ be contained within
a single block.


r~


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