[Patch AArch64] Add cpu_defines.h for AArch64.

[Ramana Radhakrishnan]

On Tue, May 19, 2015 at 4:54 PM,  <pinskia@gmail.com> wrote:
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>> On May 19, 2015, at 5:54 AM, Ramana Radhakrishnan <ramana.radhakrishnan@foss.arm.com> wrote:
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>> Hi,
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>> Like the ARM port, the AArch64 ports needs to set glibc_integral_traps to false as integer divide instructions do not trap.
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>> Bootstrapped and regression tested on aarch64-none-linux-gnu
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>> Ok to apply ?
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> Not really questioning your patch but questioning libstdc++'s defaults.
>  I wonder if this should be the default as most targets don't trap, only a few that does. And it should be safer default to say they don't trap too?


How about we  #error out if targets do *not* define some of these
defaults in libstdc++  ? There are far more ports with weak memory
models, and the defaults for _GLIBCXX_READ/WRITE_BARRIER also appear
unsafe . I was toying with a patch like that to force targets to
define this sort of thing but I need to read more of configure.host
before I make up my mind.



regards
Ramana


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> Thanks,
> Andrew
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>>
>> regards
>> Ramana
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>>
>> 2015-05-17  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>
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>>        * configure.host: Define cpu_defines_dir for AArch64
>>        * config/cpu/aarch64/cpu_defines.h: New file.
>> <0002-Do-the-same-for-AArch64.patch>