Re: VAX: Another small GAS bug?

On Thu, 2024-04-04 17:36:38 +0200, Jan-Benedict Glaw <[email protected]> wrote:

These three produced different output:
[...]
> 686         movq $0f0.0, TMPFRAC2
[...]
> 730         movd $0f0.0, TMPFRAC1
[...]
> 766         movd $0f0, (%r0)

Giving that a test on a Linux host with vax-linux configured binutils
I had readily around:
# cat test.s 
x:
        movq $0d0.0, %r4
        movd $0d0.0, %r4
        movd $0d0,   %r4



# vax-linux-as test.s
# vax-linux-objdump -w -d a.out
[...]
00000000 <x>:
   0:   7d 8f 00 00 00 00 00 00 00 00 54        movq $0x0000000000000000,r4
   b:   70 8f 00 00 00 00 00 00 00 00 54        movd $0x0000000000000000 [d-float],r4
  16:   70 8f 00 00 00 00 00 00 00 00 54        movd $0x0000000000000000 [d-float],r4


That matches the differences I got from the NetBSD I've built on a Linux
amd64 host vs. one built on a NetBSD host. Started a NetBSD amd64 VM
(Qemu, the very same thing I do the *native* NetBSD builds on), built
TOOLS and ...

nnetbsd-template# cat test.s
x:
        movq $0f0.0, %r4
        movd $0f0.0, %r4
        movd $0f0,   %r4
nnetbsd-template# ./_tools_/bin/vax--netbsdelf-as test.s
nnetbsd-template# ./_tools_/bin/vax--netbsdelf-objdump -w -d a.out 

a.out:     file format elf32-vax


Disassembly of section .text:

00000000 <x>:
   0:   7d 8f 00 00 00 00 00 00 00 00 54        movq $0x0000000000000000,r4
   b:   70 8f 00 00 00 00 00 00 00 00 54        movd $0x0000000000000000 [d-float],r4
  16:   70 8f 00 00 00 00 00 00 00 00 54        movd $0x0000000000000000 [d-float],r4



What the heck?! The original output (full unimpl_emul.S) was
different, but the critical excerpt is no longer? That'll be "fun" to
debug. Unfortunately, paid work is demanding right now, that might
take a while for me to really work on...

MfG, JBG

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