Download raw body.
ddb disassembler call
On Wed, Jun 5, 2024 at 5:54 PM Alexander Bluhm <alexander.bluhm@gmx.net> wrote:
>
> On Wed, Jun 05, 2024 at 12:00:27PM -0700, Philip Guenther wrote:
> > On Wed, Jun 5, 2024 at 8:37???AM Alexander Bluhm <bluhm@openbsd.org> wrote:
> > > -/*e8*/ { "call", 0, QUAD, op1(Dl), 0 },
> > > +/*e8*/ { "call", 0, LONG, op1(Dl), 0 },
> > > /*e9*/ { "jmp", 0, NONE, op1(Dl), 0 },
> >
> > Shouldn't it be NONE like jmp? Or maybe
> > "callq", 0, NONE
> > to look better...
>
> NONE also works
>
> ddb> x/i explicit_bzero+0x14,8
> explicit_bzero+0x14: xorl %esi,%esi
> explicit_bzero+0x16: movq %r14,%rdx
> explicit_bzero+0x19: call memset
> explicit_bzero+0x1e: movq %r15,%rdi
> explicit_bzero+0x21: movq %r14,%rsi
> explicit_bzero+0x24: popq %r14
> explicit_bzero+0x26: popq %r15
> explicit_bzero+0x28: leave
>
> objdump calls it callq, but the operand is only 4 bytes.
> Why should there be a 'q' ?
<bikeshed>
The address is a 64bit address, even if calculated from a rel32, just
like "addq %rax,$123456" has a 'q' because it's a 64bit operation
despite the immediate operand being a 32bit value.
but mostly consistency with objdump.
Don't care that much.
</bikeshed>
> --- arch/amd64/amd64/db_disasm.c 22 Apr 2023 18:26:17 -0000 1.24
> +++ arch/amd64/amd64/db_disasm.c 6 Jun 2024 00:38:32 -0000
> @@ -793,7 +793,7 @@ struct inst db_inst_table[256] = {
> /*e6*/ { "out", 0, BYTE, op2(A, Ib), 0 },
> /*e7*/ { "out", 0, LONG, op2(A, Ib) , 0 },
>
> -/*e8*/ { "call", 0, QUAD, op1(Dl), 0 },
> +/*e8*/ { "call", 0, NONE, op1(Dl), 0 },
> /*e9*/ { "jmp", 0, NONE, op1(Dl), 0 },
> /*ea*/ { "", 0, NONE, op1(OS), 0 },
> /*eb*/ { "jmp", 0, NONE, op1(Db), 0 },
ok guenther@
ddb disassembler call