Re: [Qemu-devel] QEMU+Aarch64: in_asm log skips instructions of loop-programs

[Sergey Smolov]

Peter Maydell писал 2015-09-02 19:39:
> On 2 September 2015 at 14:50, Sergey Smolov <address@hidden> wrote:
> > 02.09.2015 16:55, Sergey Smolov пишет:
> > > It seems that QEMU skips some internal instructions when generates
> > > "in_asm" log. How to eliminate this?
>
> It might help if you said what you thought was missing.
>
> -- PMM

I mean that in this example QEMU does not write to log "intermediate" 
SUBS instructions which appear in loop-unrolling process.
For me it woulb be ok if QEMU generate the following in_asm log:

[log]
IN:
0x0000000000000000:  94000001      bl #+0x4 (addr 0x4)

----------------
IN:
0x0000000000000004:  d2800140      mov x0, #0xa

----------------
IN:
0x0000000000000008:  f1000400      subs x0, x0, #0x1 (1)

----------------
IN:
0x000000000000000c:  54000040      b.eq #+0x8 (addr 0x14)

----------------
IN:
0x0000000000000008:  f1000400      subs x0, x0, #0x1 (1)

----------------
IN:
0x000000000000000c:  54000040      b.eq #+0x8 (addr 0x14)

----------------
IN:
0x0000000000000008:  f1000400      subs x0, x0, #0x1 (1)

----------------
IN:
0x000000000000000c:  54000040      b.eq #+0x8 (addr 0x14)

...
<repeat SUBS and B.EQ 8 times, if we enable also "cpu" logging mode here 
we will see that X1 register value decrements on each iteration>
...
----------------
IN:
0x0000000000000010:  17fffffd      b #-0xc (addr 0x4)
[/log]

In terms of functional programming languages (like C), my idea is to 
generate for the following program:

for (i = 0; i < 2; i++) {
   func(i);
}

the log like:
func(0)
func(1)

but QEMU generates log that contains exactly one call of "func".

Sergey Smolov