Re: [Qemu-devel] [PATCH 0/6] target/rx: Improvements to disassembly

[Yoshinori Sato <ysato@users.sourceforge.jp>]

On Tue, 28 May 2019 02:47:40 +0900,
Aleksandar Markovic wrote:
> 
> On May 27, 2019 5:44 PM, "Yoshinori Sato" <ysato@users.sourceforge.jp>
> wrote:
> >
> > On Fri, 24 May 2019 00:07:57 +0900,
> > Richard Henderson wrote:
> > >
> > > Here's a sample of the new output, taken from u-boot.bin:
> > >
> > > IN:
> > > 0xfff8000a:  fb 12 00 01 00 00          mov.l   #0x00000100, r1
> > > 0xfff80010:  fb 32 f0 13 00 00          mov.l   #0x000013f0, r3
> > > 0xfff80016:  43 13                      sub     r1, r3
> > > 0xfff80018:  fb 22 00 ea f9 ff          mov.l   #-398848, r2
> > > 0xfff8001e:  7f 8f                      smovf
> > > 0xfff80020:  ef 01                      mov.l   r0, r1
> > > 0xfff80022:  05 1e 32 00                bsr.a   fff83240
> > >
> > > IN:
> > > 0xfff83240:  72 11 5c fb                add     #-1188, r1
> > > 0xfff83244:  75 21 f0                   and     #-16, r1
> > > 0xfff83247:  02                         rts
> > >
> > > Obviously there are still a few inconsistencies in the
> > > format strings used for the immediates, but the format
> > > is readable and it is easy to look at the opcode to see
> > > how our decode compares to the manual.
> > >
> >
> > Hmm.
> > The output of the immediate value should be the same as the output of
> objdump.
> > I do not think that it is the proper format, but I did that because
> > it was useful for comparing the results.
> >
> 
> We in MIPS also use objdump output as the reference and desired output for
> QEMU disassembler (not that we are always succeeding in doing that)
> 
> Inventing propriatery QEMU output for some instructions is in my view
> counterproductive and confusing.
> 
> Sincerely,
> Aleksandar

I also considered it. Although the opcodes of RX were licensed as GPLv3,
they were not usable as they were.

> 
> > >
> > > r~
> > >
> > >
> > > Richard Henderson (6):
> > >   target/rx: Disassemble rx_index_addr into a string
> > >   target/rx: Replace operand with prt_ldmi in disassembler
> > >   target/rx: Use prt_ldmi for XCHG_mr disassembly
> > >   target/rx: Emit all disassembly in one prt()
> > >   target/rx: Collect all bytes during disassembly
> > >   target/rx: Dump bytes for each insn during disassembly
> > >
> > >  target/rx/disas.c | 366 +++++++++++++++++++++-------------------------
> > >  1 file changed, 166 insertions(+), 200 deletions(-)
> > >
> > > --
> > > 2.17.1
> > >
> >
> > --
> > Yosinori Sato
> >

-- 
Yosinori Sato