On Mon, Jun 13, 2016 at 10:36:24AM +0200, Cédric Le Goater wrote: > On 06/13/2016 09:44 AM, Thomas Huth wrote: > > On 13.06.2016 07:24, Cédric Le Goater wrote: > >> From: Benjamin Herrenschmidt <b...@kernel.crashing.org> > >> > >> There's no point inlining this, if you hit the exception case you exit > >> anyway, and not inlining saves about 100K of code size (and cache > >> footprint). > >> > >> Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org> > >> --- > >> target-ppc/translate.c | 9 ++++++--- > >> 1 file changed, 6 insertions(+), 3 deletions(-) > >> > >> diff --git a/target-ppc/translate.c b/target-ppc/translate.c > >> index f211d175c09c..600d5db2bb9a 100644 > >> --- a/target-ppc/translate.c > >> +++ b/target-ppc/translate.c > >> @@ -283,7 +283,8 @@ void gen_update_current_nip(void *opaque) > >> tcg_gen_movi_tl(cpu_nip, ctx->nip); > >> } > >> > >> -static inline void gen_exception_err(DisasContext *ctx, uint32_t excp, > >> uint32_t error) > >> +static void __attribute__((noinline)) > >> +gen_exception_err(DisasContext *ctx, uint32_t excp, uint32_t error) > >> { > >> TCGv_i32 t0, t1; > >> if (ctx->exception == POWERPC_EXCP_NONE) { > >> @@ -297,7 +298,8 @@ static inline void gen_exception_err(DisasContext > >> *ctx, uint32_t excp, uint32_t > >> ctx->exception = (excp); > >> } > >> > >> -static inline void gen_exception(DisasContext *ctx, uint32_t excp) > >> +static void __attribute__((noinline)) > >> +gen_exception(DisasContext *ctx, uint32_t excp) > >> { > >> TCGv_i32 t0; > >> if (ctx->exception == POWERPC_EXCP_NONE) { > >> @@ -309,7 +311,8 @@ static inline void gen_exception(DisasContext *ctx, > >> uint32_t excp) > >> ctx->exception = (excp); > >> } > >> > >> -static inline void gen_debug_exception(DisasContext *ctx) > >> +static void __attribute__((noinline)) > >> +gen_debug_exception(DisasContext *ctx) > >> { > >> TCGv_i32 t0; > > > > Do you get the same results if you just remove the "inline" keyword, > > without adding the "__attribute__((noinline))" ? If yes, I'd suggest to > > do this patch without the "__attribute__((noinline))" - that's easier to > > read, and the compiler can still decide to inline something in case it's > > better one a certain architecture. > > Yes. They are no differences. > > The interesting part though is that the .text is about the same size. > There is even a slight increase of ~2K with gcc 4.9.2 (intel host) and > a slight decrease of ~1K with gcc 5.3.1 (ppc64le host). > > I guess we can just drop that patch. It does not seem to bring much.
I would prefer to see the inline keyword removed. Except in the case of tiny header functions, it's very rarely a good idea - usually the compiler will have better information on whether to inline or not. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson
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