1480581 - EndianUtils.h needs to know that aarch64 windows is a thing

Status: RESOLVED FIXED

(Core :: MFBT, enhancement)

Description

[Nathan Froyd [:froydnj]]

...because it has this giant conditional of architectures to determine endianness.

Or we could just use the endianness result from configure in this header and call it a day.

Comment 1

[Nathan Froyd [:froydnj]]

Attachment: add an AArch64-specific case to EndianUtils.h

I took the lazy way out.

Comment 2

[Mike Hommey [:glandium]]

Comment on attachment 8997245 [details] [diff] [review]
add an AArch64-specific case to EndianUtils.h

Review of attachment 8997245 [details] [diff] [review]:
-----------------------------------------------------------------

::: mfbt/EndianUtils.h
@@ +82,5 @@
>  #  pragma intrinsic(_byteswap_uint64)
>  #endif
>  
>  #if defined(_WIN64)
>  #  if defined(_M_X64) || defined(_M_AMD64) || defined(_AMD64_)

|| defined(_M_ARM64) ?

Comment 3

[Nathan Froyd [:froydnj]]

(In reply to Mike Hommey [:glandium] from comment #2)
> ::: mfbt/EndianUtils.h
> @@ +82,5 @@
> >  #  pragma intrinsic(_byteswap_uint64)
> >  #endif
> >  
> >  #if defined(_WIN64)
> >  #  if defined(_M_X64) || defined(_M_AMD64) || defined(_AMD64_)
> 
> || defined(_M_ARM64) ?

The arm case in the _WIN32 arm below was separate from the x86 case, so I was just following prior art.  I'm not particularly attached either way, though.  WDYT?

Comment 4

[Mike Hommey [:glandium]]

I'm almost tempted to say at this point we could just say that Windows = little endian. It's very unlikely that a future windows platform would be big endian now. Waldo, what's your take?

Comment 5

[Jeff Walden [:Waldo]]

I'd probably put good money on Windows we would ever target never ever being big-endian.  But as long as it isn't a serious hardship to divine endianness from architecture and not from target OS, I think we should keep doing that.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/023e8e5e6fb2
add an AArch64-specific case to EndianUtils.h; r=Waldo

Comment 7

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/023e8e5e6fb2