Re: [Qemu-devel] MIPS 'move' insn emulation

[Sergey Smolov]

On 14.09.2017 16:58, Peter Maydell wrote:
> At translate time it is generating some extra code which at runtime
> will call the helper_trace_reg_access() function, passing it the
> values in the registers at this point. This will result in poor
> performance if you do it for frequently executed instructions.

Ok, thank you.

> That looks like it ought to work. Check you really did save all your
> files in your editor before compiling? :-)

Yes, I did. These warnings are very suspicious, because they come with 
strange numbers of MIPS GPR registers that I receive for my program.

Here is the program:

.text
    addiu $8, $zero, 0x7
    move $9, $8
    sll $8, $8, 3
    add $8, $8, $9

Here is the log that helper functions provide:

$0 00000007
$7 00000007
$0 00000038
$0 0000003f

The first value is register name, the second is the value to be written. 
Values are ok, but I expect to see $8 and $9  registers here.

> PS: there's no point passing the env pointer into the function if
> you're not going to use it...

I thought that I need to pass env pointer to helper function because of 
some convention. Again, thank you for the note.

--
Sincerely yours,
Sergey Smolov