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

[Christophe Leroy]

Le 08/08/2025 à 15:54, Ruben Wauters a écrit :

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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 :

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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 <rubenr...@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)

Ok.


Reviewed-by: Christophe Leroy <christophe.le...@csgroup.eu>

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