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64 bit assembler => UASM Assembler Development => Topic started by: Biterider on February 26, 2020, 03:39:20 AM

Title: vmovdqu issue
Post by: Biterider on February 26, 2020, 03:39:20 AM

Hi
I'm having some problems with the vmovdqu instruction. It seems that the memory argument is not being encoded correctly or I'm doing something wrong.
The test code is very simple:

Code: [Select]

.data
MyYmm YMMWORD 123456789012345678901234567890

.code
start proc
  vmovdqu ymm0, MyYmm
  ret
start endp

The debug output looks like:

Code: [Select]

00007FF615751000 C5 FE 6F 85 F8 1F 00 00 vmovdqu     ymm0,ymmword ptr [rbp+1FF8h] 
00007FF615751008 C3                   ret 
triggering a GPF.

Regards, Biterider

Title: Re: vmovdqu issue
Post by: jj2007 on February 26, 2020, 04:00:16 AM

Same with 32-bit code. Where does the [?bp... creep in?

ML 14.0 assembles it as follows (but complains about bad data initialiser etc):
0040658A                ³.  C5FE:6F05 00704000      vmovdqu ymm0, [407000]

Title: Re: vmovdqu issue
Post by: Biterider on February 26, 2020, 06:12:02 AM

Hi
Playing a bit with this instruction, I've noticed that writing the ymm register back to memory is encoded correctly.


Biterider

Title: Re: vmovdqu issue
Post by: habran on February 26, 2020, 11:17:19 AM

Hi Biterider,
good find, this is definitely a bug :thumbsup:
It works fine with a new codegen.c and it will be easy fixed in next release:

Code: [Select]

000000013FF35A3C C5 FE 6F 05 7F 5C 00 00 vmovdqu     ymm0,ymmword ptr [MyYmm (013FF3B6C3h)Thanks :biggrin:

Title: Re: vmovdqu issue
Post by: Biterider on February 27, 2020, 01:02:26 AM

Hi habran
Thank you for addressing this issue. Do you have an idea when do you will get a fix?
In the meantime, I'm going to replace vmovdqu with vlddqu, which does a similar job.

Biterider

Title: Re: vmovdqu issue
Post by: habran on February 27, 2020, 11:13:12 AM

Hi Biterider,
I don't know if John is available to upload the fix so I attached InstrTablev2.h for you
replace the one in H folder with this one and build uasm source
that will fix the problem.

Title: Re: vmovdqu issue
Post by: Biterider on February 28, 2020, 12:26:29 AM

Thank you Habran!

Title: Re: vmovdqu issue
Post by: johnsa on April 17, 2020, 04:42:19 AM

This fix is now also on 2.50 branch on Git.

Title: Re: vmovdqu issue
Post by: Biterider on April 18, 2020, 03:18:31 AM

 :thumbsup: