powerpc: Add a ppc_inst_as_str() helper

There are quite a few places where instructions are printed, this is
done using a '%x' format specifier. With the introduction of prefixed
instructions, this does not work well. Currently in these places,
ppc_inst_val() is used for the value for %x so only the first word of
prefixed instructions are printed.

When the instructions are word instructions, only a single word should
be printed. For prefixed instructions both the prefix and suffix should
be printed. To accommodate both of these situations, instead of a '%x'
specifier use '%s' and introduce a helper, __ppc_inst_as_str() which
returns a char *. The char * __ppc_inst_as_str() returns is buffer that
is passed to it by the caller.

It is cumbersome to require every caller of __ppc_inst_as_str() to now
declare a buffer. To make it more convenient to use __ppc_inst_as_str(),
wrap it in a macro that uses a compound statement to allocate a buffer
on the caller's stack before calling it.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
[mpe: Drop 0x prefix to match most existings uses, especially xmon]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200602052728.18227-1-jniethe5@gmail.com

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index f08b2ef1995a..8df83a744528 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2977,7 +2977,7 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
 		dotted = 0;
 		last_inst = inst;
 		if (praddr)
-			printf(REG"  %.8x", adr, ppc_inst_val(inst));
+			printf(REG"  %s", adr, ppc_inst_as_str(inst));
 		printf("\t");
 		dump_func(ppc_inst_val(inst), adr);
 		printf("\n");