From: Michael Meissner <meissner@linux.ibm.com>
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Michael Meissner <meissner@linux.ibm.com>,
gcc-patches@gcc.gnu.org, David Edelsohn <dje.gcc@gmail.com>
Subject: Re: [PATCH, V4] PowerPC Turn on -mpcrel by default for -mcpu=future
Date: Tue, 21 Apr 2020 14:03:34 -0400 [thread overview]
Message-ID: <20200421180334.GA19690@ibm-tinman.the-meissners.org> (raw)
In-Reply-To: <20200407225801.GE26902@gate.crashing.org>
On Tue, Apr 07, 2020 at 05:58:01PM -0500, Segher Boessenkool wrote:
> > + /* Enable -mprefixed by default on 64-bit 'future' systems. */
> > + if (TARGET_FUTURE && TARGET_POWERPC64
> > + && (rs6000_isa_flags_explicit & OPTION_MASK_PREFIXED) == 0)
> > + rs6000_isa_flags |= OPTION_MASK_PREFIXED;
>
> I don't understand why only for 64 bit?
I have doubts whether PC-relative really works with 32-bit. I suspect that you
may see some hidden wrap around issues if an address crosses the 32-bit
boundary. Given the simulator I have access to only runs Linux 64-bit, I have
no way of testing it. I would prefer to not put in code that I can't test.
But if the only way to get the patch in is to remove the test, I can remove it.
--
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meissner@linux.ibm.com, phone: +1 (978) 899-4797
next prev parent reply other threads:[~2020-04-21 18:03 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-06 16:52 Michael Meissner
2020-04-06 22:21 ` will schmidt
2020-04-07 22:58 ` Segher Boessenkool
2020-04-21 18:03 ` Michael Meissner [this message]
2020-04-21 19:15 ` Segher Boessenkool
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