new triplet for x32 psABI?

H.J. Lu hjl.tools@gmail.com
Tue Oct 4 00:54:00 GMT 2011


On Mon, Oct 3, 2011 at 4:47 PM, Michael LIAO <michael.hliao@gmail.com> wrote:
> On Mon, Oct 3, 2011 at 4:03 PM, Mike Frysinger <vapier@gentoo.org> wrote:
>> On Monday, October 03, 2011 18:57:28 Michael LIAO wrote:
>>
>> please don't top post
>>
>
> sorry, it's my first post on mailing.
>
>>> Most examples would be related to tools generating code.
>>>
>>> Suppose you have a software package with several hard-coded fully
>>> optimized assembly file for different targets. Your build system need
>>> to know the current target as well as target ABI to select the correct
>>> assembly file to build it. It even desirable if it includes a simple
>>> script to help generate assembly code (like the one in OpenSSL), you'd
>>> better know the target ABI to prepare proper glue code without
>>> breaking ABI.
>>
>> hjlu posted examples to the x32 site as to handle this.  the only difference
>> between x86_64 and x32 is the size of the pointers.
>>
>
> Besides the pointer size, there are other differences like indirect
> branch which need different code sequence on x32 and x64. Indirect
> branch would be used in assembly code (yeah, concrete example would
> valuable here but indirect branch should be used potentially and
> possibly in assembly code.) If the assembly code use indirect branch,
> it needs to know the target ABI and generate/use difference code path.
>

In assembly codes, most, if not all, of x86-64 indirect branch work fine for x32


-- 
H.J.



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