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Re: [tree-ssa] Block merging (updated)


In message <20040113124115.GA7389@atrey.karlin.mff.cuni.cz>, Zdenek Dvorak writ
es:
 >Hello,
 >
 >> +   /* Remove labels from B and set bb_for_stmt to A for other statements. 
 > */
 >> +   for (bsi = bsi_start (b); !bsi_end_p (bsi);)
 >> +     {
 >> +       if (TREE_CODE (bsi_stmt (bsi)) == LABEL_EXPR)
 >> +       bsi_remove (&bsi);
 >> +       else
 >> +       {
 >> +         set_bb_for_stmt (bsi_stmt (bsi), a);
 >> +         bsi_next (&bsi);
 >> +       }
 >> +     }
 >> 
 >> 
 >> This will remove user-declared labels.  IIRC some people wanted these to be
 >> preserved, e.g. for debugging purposes.  Perhaps tree_can_merge_blocks_p
 >> should be false if a user label heads the basic block.
 >
 >there is IMHO no point in this, since rtl level cfgcleanup would do the
 >merging and removing of the label anyway.
If the RTL cfgcleanup is removing a user label, then that code is buggy.

Please avoid removing user declared labels.

jeff


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