From: Aurelien Jarno <aurelien@aurel32.net>
To: Blue Swirl <blauwirbel@gmail.com>
Cc: Andrzej Zaborowski <andrew.zaborowski@intel.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] tcg: add div/rem 32-bit helpers
Date: Sat, 6 Mar 2010 11:30:05 +0100 [thread overview]
Message-ID: <20100306103005.GD5860@hall.aurel32.net> (raw)
In-Reply-To: <f43fc5581003052315i3956bd37h5e490c24a3d362a2@mail.gmail.com>
On Sat, Mar 06, 2010 at 09:15:38AM +0200, Blue Swirl wrote:
> On 3/4/10, Aurelien Jarno <aurelien@aurel32.net> wrote:
> > Some targets like ARM would benefit to use 32-bit helpers for
> > div/rem/divu/remu.
> >
> > Create a #define for div2 so that targets can select between
> > div, div2 and helper implementation. Use the helper version if none
> > of the #define are present.
> >
> > Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
> > ---
> > tcg-runtime.c | 24 +++++++++++++++++++
> > tcg/arm/tcg-target.h | 1 +
> > tcg/hppa/tcg-target.h | 1 +
> > tcg/i386/tcg-target.h | 1 +
> > tcg/tcg-op.h | 57 +++++++++++++++++++++++++++++++++++++++++++++-
> > tcg/tcg-runtime.h | 5 ++++
> > tcg/x86_64/tcg-target.h | 2 +
> > 7 files changed, 89 insertions(+), 2 deletions(-)
> >
> > diff --git a/tcg-runtime.c b/tcg-runtime.c
> > index 219cade..abfc364 100644
> > --- a/tcg-runtime.c
> > +++ b/tcg-runtime.c
> > @@ -25,6 +25,30 @@
> >
> > #include "tcg/tcg-runtime.h"
> >
> > +/* 32-bit helpers */
> > +
> > +int32_t tcg_helper_div_i32(int32_t arg1, int32_t arg2)
> > +{
> > + return arg1 / arg2;
> > +}
> > +
> > +int32_t tcg_helper_rem_i32(int32_t arg1, int32_t arg2)
> > +{
> > + return arg1 % arg2;
> > +}
> > +
> > +uint32_t tcg_helper_divu_i32(uint32_t arg1, uint32_t arg2)
> > +{
> > + return arg1 / arg2;
> > +}
> > +
> > +uint32_t tcg_helper_remu_i32(uint32_t arg1, uint32_t arg2)
> > +{
> > + return arg1 % arg2;
> > +}
> > +
> > +/* 64-bit helpers */
> > +
> > int64_t tcg_helper_shl_i64(int64_t arg1, int64_t arg2)
> > {
> > return arg1 << arg2;
> > diff --git a/tcg/arm/tcg-target.h b/tcg/arm/tcg-target.h
> > index 4cad967..4b2b0be 100644
> > --- a/tcg/arm/tcg-target.h
> > +++ b/tcg/arm/tcg-target.h
> > @@ -56,6 +56,7 @@ enum {
> > #define TCG_TARGET_CALL_STACK_OFFSET 0
> >
> > /* optional instructions */
> > +#define TCG_TARGET_HAS_div2_i32
>
> Please also add commented out #defines for targets that do not
> implement div2 yet.
I don't really see the point. The targets should implement either
div/rem or div2, depending on their instruction set. Implementing div2
on a targets which have separate instructions to compute div and rem
will impact the performances negatively.
> > #define TCG_TARGET_HAS_ext8s_i32
> > #define TCG_TARGET_HAS_ext16s_i32
> > // #define TCG_TARGET_HAS_ext8u_i32
> > diff --git a/tcg/hppa/tcg-target.h b/tcg/hppa/tcg-target.h
> > index 7ab6f0c..fa39bfc 100644
> > --- a/tcg/hppa/tcg-target.h
> > +++ b/tcg/hppa/tcg-target.h
> > @@ -75,6 +75,7 @@ enum {
> > #define TCG_TARGET_STACK_GROWSUP
> >
> > /* optional instructions */
> > +#define TCG_TARGET_HAS_div2_i32
> > //#define TCG_TARGET_HAS_ext8s_i32
> > //#define TCG_TARGET_HAS_ext16s_i32
> > //#define TCG_TARGET_HAS_bswap16_i32
> > diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h
> > index f97034c..e994fd5 100644
> > --- a/tcg/i386/tcg-target.h
> > +++ b/tcg/i386/tcg-target.h
> > @@ -45,6 +45,7 @@ enum {
> > #define TCG_TARGET_CALL_STACK_OFFSET 0
> >
> > /* optional instructions */
> > +#define TCG_TARGET_HAS_div2_i32
> > #define TCG_TARGET_HAS_rot_i32
> > #define TCG_TARGET_HAS_ext8s_i32
> > #define TCG_TARGET_HAS_ext16s_i32
> > diff --git a/tcg/tcg-op.h b/tcg/tcg-op.h
> > index 6ae1760..c71e1a8 100644
> > --- a/tcg/tcg-op.h
> > +++ b/tcg/tcg-op.h
> > @@ -365,6 +365,19 @@ static inline void tcg_gen_helperN(void *func, int flags, int sizemask,
> > }
> >
> > /* FIXME: Should this be pure? */
> > +static inline void tcg_gen_helper32(void *func, TCGv_i32 ret,
> > + TCGv_i32 a, TCGv_i32 b)
> > +{
> > + TCGv_ptr fn;
> > + TCGArg args[2];
> > + fn = tcg_const_ptr((tcg_target_long)func);
> > + args[0] = GET_TCGV_I32(a);
> > + args[1] = GET_TCGV_I32(b);
> > + tcg_gen_callN(&tcg_ctx, fn, 0, 0, GET_TCGV_I32(ret), 2, args);
> > + tcg_temp_free_ptr(fn);
> > +}
> > +
> > +/* FIXME: Should this be pure? */
> > static inline void tcg_gen_helper64(void *func, TCGv_i64 ret,
> > TCGv_i64 a, TCGv_i64 b)
> > {
> > @@ -635,7 +648,7 @@ static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > {
> > tcg_gen_op3_i32(INDEX_op_remu_i32, ret, arg1, arg2);
> > }
> > -#else
> > +#elif defined(TCG_TARGET_HAS_div2_i32)
> > static inline void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > {
> > TCGv_i32 t0;
> > @@ -671,6 +684,26 @@ static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > tcg_gen_op5_i32(INDEX_op_divu2_i32, t0, ret, arg1, t0, arg2);
> > tcg_temp_free_i32(t0);
> > }
> > +#else
> > +static inline void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > +{
> > + tcg_gen_helper32(tcg_helper_div_i32, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_rem_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > +{
> > + tcg_gen_helper32(tcg_helper_rem_i32, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_divu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > +{
> > + tcg_gen_helper32(tcg_helper_divu_i32, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
> > +{
> > + tcg_gen_helper32(tcg_helper_remu_i32, ret, arg1, arg2);
> > +}
> > #endif
> >
> > #if TCG_TARGET_REG_BITS == 32
> > @@ -1135,7 +1168,7 @@ static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > {
> > tcg_gen_op3_i64(INDEX_op_remu_i64, ret, arg1, arg2);
> > }
> > -#else
> > +#elif defined(TCG_TARGET_HAS_div2_i64)
> > static inline void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > {
> > TCGv_i64 t0;
> > @@ -1171,6 +1204,26 @@ static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > tcg_gen_op5_i64(INDEX_op_divu2_i64, t0, ret, arg1, t0, arg2);
> > tcg_temp_free_i64(t0);
> > }
> > +#else
> > +static inline void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > +{
> > + tcg_gen_helper64(tcg_helper_div_i64, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_rem_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > +{
> > + tcg_gen_helper64(tcg_helper_rem_i64, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_divu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > +{
> > + tcg_gen_helper64(tcg_helper_divu_i64, ret, arg1, arg2);
> > +}
> > +
> > +static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
> > +{
> > + tcg_gen_helper64(tcg_helper_remu_i64, ret, arg1, arg2);
> > +}
> > #endif
> >
> > #endif
> > diff --git a/tcg/tcg-runtime.h b/tcg/tcg-runtime.h
> > index e750cc1..5615b13 100644
> > --- a/tcg/tcg-runtime.h
> > +++ b/tcg/tcg-runtime.h
> > @@ -2,6 +2,11 @@
> > #define TCG_RUNTIME_H
> >
> > /* tcg-runtime.c */
> > +int32_t tcg_helper_div_i32(int32_t arg1, int32_t arg2);
> > +int32_t tcg_helper_rem_i32(int32_t arg1, int32_t arg2);
> > +uint32_t tcg_helper_divu_i32(uint32_t arg1, uint32_t arg2);
> > +uint32_t tcg_helper_remu_i32(uint32_t arg1, uint32_t arg2);
> > +
> > int64_t tcg_helper_shl_i64(int64_t arg1, int64_t arg2);
> > int64_t tcg_helper_shr_i64(int64_t arg1, int64_t arg2);
> > int64_t tcg_helper_sar_i64(int64_t arg1, int64_t arg2);
> > diff --git a/tcg/x86_64/tcg-target.h b/tcg/x86_64/tcg-target.h
> > index 765f0b4..d1e8b9e 100644
> > --- a/tcg/x86_64/tcg-target.h
> > +++ b/tcg/x86_64/tcg-target.h
> > @@ -56,6 +56,8 @@ enum {
> > #define TCG_TARGET_CALL_STACK_OFFSET 0
> >
> > /* optional instructions */
> > +#define TCG_TARGET_HAS_div2_i32
> > +#define TCG_TARGET_HAS_div2_i64
> > #define TCG_TARGET_HAS_bswap16_i32
> > #define TCG_TARGET_HAS_bswap16_i64
> > #define TCG_TARGET_HAS_bswap32_i32
> >
> > --
> > 1.7.0
> >
> >
> >
> >
>
>
>
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurelien@aurel32.net http://www.aurel32.net
next prev parent reply other threads:[~2010-03-06 10:30 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-04 21:36 [Qemu-devel] [PATCH] tcg: add div/rem 32-bit helpers Aurelien Jarno
2010-03-06 7:15 ` Blue Swirl
2010-03-06 10:30 ` Aurelien Jarno [this message]
2010-03-06 11:15 ` malc
2010-03-06 11:32 ` Blue Swirl
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