Re: [patch] cfglayout fixes

[Jakub Jelinek <jakub at redhat dot com>]

On Thu, Dec 06, 2012 at 01:48:31PM +0100, Steven Bosscher wrote:
>         * bitmap.h: Fix "set_difference" references in comment.
>         * dse.c (dse_bitmap_obstack): Fix comment.

This is ok.
> 
>         * loop-invariant.c (record_use): Use DF_REF_REG_MEM_P instead of
>         looking at specific flags.

So is this.

>         * cfgrtl.c (rtl_verify_flow_info): Fix code style (indentation).

This is undesirable, we generally don't fix indentation unless you touch
the code (or very close surrounding code), yeah, we have lots of formatting
issues (some people don't use tabs at all, etc.), but doing just formatting
changes means making svn blame/git blame less useful.

>         (fixup_reorder_chain): Set cfg_layout_function_header to NULL to
>         avoid dangling pointers into GC-allocated insns.  Clear BB_HEADER,
>         BB_FOOTER, and cfg_layout_function_footer for the same reason.
>         Do not link new barriers for cfgrtl mode to cfglayout's BB_FOOTER.
>         * combine.c (combine_instructions): Fix end-of-block check to not
>         expect BARRIERs, which may not exist in cfglayout mode.

For the rest, I wonder if this really is stage3 material.  Do you have a
testcase that ICEs or is miscompiled without the changes?  For the two GTY
vars, perhaps we could temporarily clear them in clear_after_compilation
instead.

	Jakub