libjava build failure sol2.6 asm problem?

[Jeff Sturm]

On Wed, 19 Dec 2001, Richard Henderson wrote:
> On Wed, Dec 19, 2001 at 02:46:29PM -0500, Jeff Sturm wrote:
> >  	  /* shit */
> > +	  LABEL_PRESERVE_P (XEXP (operands[1], 0)) = 1;
> >  	  emit_insn (gen_movsi_pic_label_ref (operands[0], operands[1]));
> >  	  DONE;
> 
> This shouldn't be done with labels at all.  And in fact, I can't
> see where load_pic_register would use such a thing; it's probably
> garbage.

OK, I'm confused.  This has nothing to do with load_pic_register,
which is always emitted in the prologue; it's doing a movsi with a
LABEL_REF operand (in the context of an EH cleanup).

Without PIC, we're emitting:

        sethi   %hi(.LL38), %o0
        or      %o0, %lo(.LL38), %i0

so we can later branch back to .LL38:

        jmp     %i0
 
Fine so far.  With PIC this becomes:

        sethi   %hi(_GLOBAL_OFFSET_TABLE_-(.LL39-.)), %o0
        or      %o0, %lo(_GLOBAL_OFFSET_TABLE_-(.LL39-.)), %o0
...
        sub     %l7, %o0, %i0
	jmp	%i0 

(In the latter case the label is somehow deleted, thus the bug report.)
Now what part of this is garbage?  What should movsi do differently for
PIC?

Jeff