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Re: how to keep a hard register across multiple instrutions?
- From: Joern Rennecke <joern dot rennecke at embecosm dot com>
- To: David Kang <dkang at isi dot edu>
- Cc: Jeff Law <law at redhat dot com>, GCC <gcc at gcc dot gnu dot org>
- Date: Mon, 3 Nov 2014 22:05:21 +0000
- Subject: Re: how to keep a hard register across multiple instrutions?
- Authentication-results: sourceware.org; auth=none
- References: <5457ABA6 dot 5020107 at redhat dot com> <1356644080 dot 977264 dot 1415051515787 dot JavaMail dot root at zm dot isi dot edu>
On 3 November 2014 21:51, David Kang <email@example.com> wrote:
> Thank you for the tips.
> I tried the following condition for split.
> "reload_completed && FP_REG_P (operands)"
> But, the registers are still changed.
> How can I specify "after register allocation" in the split condition?
Are you sure that your problem is that the split is too early, or
could you suffering
from later register renumbering?
You can get a set of dump files for all rtl passes by adding the -da
option to gcc / cc1,
so that you can see exactly when things go wrong.
I would suspect the register renaming pass causing you trouble.
You might have to define HARD_REGNO_RENAME_OK suitably for your target.