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[PATCH GCC][04/13]Sort statements in topological order for loop distribution

From: Bin Cheng <Bin dot Cheng at arm dot com>
To: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
Cc: nd <nd at arm dot com>
Date: Mon, 12 Jun 2017 17:02:45 +0000
Subject: [PATCH GCC][04/13]Sort statements in topological order for loop distribution
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Hi,
During the work I ran into a latent bug for distributing.  For the moment we sort statements
in dominance order, but that's not enough because basic blocks may be sorted in reverse order
of execution flow.  This results in wrong data dependence direction later.  This patch fixes
the issue by sorting in topological order.

Bootstrap and test on x86_64 and AArch64.  Is it OK?

Thanks,
bin
2017-06-07  Bin Cheng  <bin.cheng@arm.com>

	* tree-loop-distribution.c (bb_top_order_index): New.
	(bb_top_order_index_size, bb_top_order_cmp): New.
	(stmts_from_loop): Use topological order.
	(pass_loop_distribution::execute): Compute topological order for.
	basic blocks.

Attachment: 0004-sort-stmts-in-top-order-20170607.txt
Description: 0004-sort-stmts-in-top-order-20170607.txt

Follow-Ups:
- Re: [PATCH GCC][04/13]Sort statements in topological order for loop distribution
  - From: Richard Biener

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