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Re: [PATCH] PR 62173, re-shuffle insns for RTL loop invariant hoisting
- From: Steven Bosscher <stevenb dot gcc at gmail dot com>
- To: Jiong Wang <wong dot kwongyuan dot tools at gmail dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>, Kenneth Zadeck <zadeck at naturalbridge dot com>, Jeff Law <law at redhat dot com>, Richard Biener <richard dot guenther at gmail dot com>, "Bin.Cheng" <amker dot cheng at gmail dot com>, Segher Boessenkool <segher at kernel dot crashing dot org>
- Date: Tue, 14 Apr 2015 18:48:42 +0200
- Subject: Re: [PATCH] PR 62173, re-shuffle insns for RTL loop invariant hoisting
- Authentication-results: sourceware.org; auth=none
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On Tue, Apr 14, 2015 at 5:06 PM, Jiong Wang wrote:
> but, after some investigation I found gcc actually generate difference
> code when debug info enabled because
> DEBUG_INSN will affect data flow analysis.
It should not, so that's a bug.
> So I think this stage2/3 binary difference is acceptable?
No, they should be identical. If there's a difference, then there's a
bug - which, it seems, you've already found, too.
Ciao!
Steven