Re: [PATCH] powerpc/xmon: replace sizeof calculations with ARRAY_SIZE macro

[Ruben Wauters <rubenru09@aol.com>]

On Thu, 2025-07-31 at 17:40 +0100, Ruben Wauters wrote:
> On Wed, 2025-07-30 at 08:14 +0200, Christophe Leroy wrote:
> > 
> > 
> > Le 20/07/2025 à 00:43, Ruben Wauters a écrit :
> > > [Vous ne recevez pas souvent de courriers de rubenru09@aol.com.
> > > Découvrez pourquoi ceci est important à
> > > https://aka.ms/LearnAboutSenderIdentification ]
> > > 
> > > The calculations for operand/opcode/macro numbers are done in an
> > > identical manner to the already existing ARRAY_SIZE macro in
> > > linux/array_size.h
> > > 
> > > This patch replaces the sizeof calculations with the macro to
> > > make
> > > the
> > > code cleaner and more immediately obvious what it is doing.
> > > 
> > > Signed-off-by: Ruben Wauters <rubenru09@aol.com>
> > > ---
> > >   arch/powerpc/xmon/ppc-opc.c | 16 ++++++----------
> > 
> > This file is mostly taken from binutils, refer commit 08d96e0b127e 
> > ("powerpc/xmon: Apply binutils changes to upgrade disassembly").
> > 
> > I think your change should be done in binutils then backported to
> > the
> > kernel. The more we diverge from binutils the worse it is
> 
> While this is somewhat reasonable, the header (linux/array_size.h) is
> linux specific, and is included through kernel.h
> 
> I can probably see if binutils has a similar header, or if they would
> accept an equivalent header to make the file equivalent, but I'm
> unsure
> if they would
> 
Hello, I have checked the binutils source, and have noticed that
binutils already uses the ARRAY_SIZE macro, and this patch actually
brings the kernel more in line with the equivalent file in binutils
(opcodes/ppc-opc.c)

As such, I would like to request that the patch be applied as-is.

Thank you

Ruben

> Ruben
> 
> > Christophe
> > 
> > 
> > >   1 file changed, 6 insertions(+), 10 deletions(-)
> > > 
> > > diff --git a/arch/powerpc/xmon/ppc-opc.c b/arch/powerpc/xmon/ppc-
> > > opc.c
> > > index 0774d711453e..de9b4236728c 100644
> > > --- a/arch/powerpc/xmon/ppc-opc.c
> > > +++ b/arch/powerpc/xmon/ppc-opc.c
> > > @@ -954,8 +954,7 @@ const struct powerpc_operand
> > > powerpc_operands[]
> > > =
> > >     { 0xff, 11, NULL, NULL, PPC_OPERAND_SIGNOPT },
> > >   };
> > > 
> > > -const unsigned int num_powerpc_operands = (sizeof
> > > (powerpc_operands)
> > > -                                          / sizeof
> > > (powerpc_operands[0]));
> > > +const unsigned int num_powerpc_operands =
> > > ARRAY_SIZE(powerpc_operands);
> > > 
> > >   /* The functions used to insert and extract complicated
> > > operands.  */
> > > 
> > > @@ -6968,9 +6967,8 @@ const struct powerpc_opcode
> > > powerpc_opcodes[]
> > > = {
> > >   {"fcfidu.",    XRC(63,974,1),  XRA_MASK, POWER7|PPCA2,
> > > PPCVLE,         {FRT, FRB}},
> > >   };
> > > 
> > > -const int powerpc_num_opcodes =
> > > -  sizeof (powerpc_opcodes) / sizeof (powerpc_opcodes[0]);
> > > -
> > > +const int powerpc_num_opcodes = ARRAY_SIZE(powerpc_opcodes);
> > > +
> > >   /* The VLE opcode table.
> > > 
> > >      The format of this opcode table is the same as the main
> > > opcode
> > > table.  */
> > > @@ -7207,9 +7205,8 @@ const struct powerpc_opcode vle_opcodes[] =
> > > {
> > >   {"se_bl",      BD8(58,0,1),    BD8_MASK,       PPCVLE,
> > > 0,              {B8}},
> > >   };
> > > 
> > > -const int vle_num_opcodes =
> > > -  sizeof (vle_opcodes) / sizeof (vle_opcodes[0]);
> > > -
> > > +const int vle_num_opcodes = ARRAY_SIZE(vle_opcodes);
> > > +
> > >   /* The macro table.  This is only used by the assembler.  */
> > > 
> > >   /* The expressions of the form (-x ! 31) & (x | 31) have the
> > > value 0
> > > @@ -7276,5 +7273,4 @@ const struct powerpc_macro powerpc_macros[]
> > > =
> > > {
> > >   {"e_clrlslwi",4, PPCVLE, "e_rlwinm %0,%1,%3,(%2)-(%3),31-
> > > (%3)"},
> > >   };
> > > 
> > > -const int powerpc_num_macros =
> > > -  sizeof (powerpc_macros) / sizeof (powerpc_macros[0]);
> > > +const int powerpc_num_macros = ARRAY_SIZE(powerpc_macros);
> > > --
> > > 2.49.1
> > >