| Message ID | 82376447-482D-43AA-99FA-73C4A7484615@nokia.com |
|---|---|
| State | New |
| Headers | show |
On Wed, Oct 21, 2009 at 12:17 PM, <Juha.Riihimaki@nokia.com> wrote: > Current implementation of thumb mul instruction is implemented as a > 32x32->64 multiply which then uses only 32 least significant bits of > the result. Replace that with a simple 32x32->32 multiply. > > Signed-off-by: Juha Riihimäki <juha.riihimaki@nokia.com> Acked-by: Laurent Desnogues <laurent.desnogues@gmail.com> > --- > diff --git a/target-arm/translate.c b/target-arm/translate.c > index bda105e..3ea9d51 100644 > --- a/target-arm/translate.c > +++ b/target-arm/translate.c > @@ -310,22 +310,6 @@ static TCGv_i64 gen_muls_i64_i32(TCGv a, TCGv b) > return tmp1; > } > > -/* Unsigned 32x32->64 multiply. */ > -static void gen_mull(TCGv a, TCGv b) > -{ > - TCGv_i64 tmp1 = tcg_temp_new_i64(); > - TCGv_i64 tmp2 = tcg_temp_new_i64(); > - > - tcg_gen_extu_i32_i64(tmp1, a); > - tcg_gen_extu_i32_i64(tmp2, b); > - tcg_gen_mul_i64(tmp1, tmp1, tmp2); > - tcg_temp_free_i64(tmp2); > - tcg_gen_trunc_i64_i32(a, tmp1); > - tcg_gen_shri_i64(tmp1, tmp1, 32); > - tcg_gen_trunc_i64_i32(b, tmp1); > - tcg_temp_free_i64(tmp1); > -} > - > /* Signed 32x32->64 multiply. */ > static void gen_imull(TCGv a, TCGv b) > { > @@ -8358,7 +8342,7 @@ static void disas_thumb_insn(CPUState *env, > DisasContext *s) > gen_logic_CC(tmp); > break; > case 0xd: /* mul */ > - gen_mull(tmp, tmp2); > + tcg_gen_mul_i32(tmp, tmp, tmp2); > if (!s->condexec_mask) > gen_logic_CC(tmp); > break; >
diff --git a/target-arm/translate.c b/target-arm/translate.c index bda105e..3ea9d51 100644 --- a/target-arm/translate.c +++ b/target-arm/translate.c @@ -310,22 +310,6 @@ static TCGv_i64 gen_muls_i64_i32(TCGv a, TCGv b) return tmp1; } -/* Unsigned 32x32->64 multiply. */ -static void gen_mull(TCGv a, TCGv b) -{ - TCGv_i64 tmp1 = tcg_temp_new_i64(); - TCGv_i64 tmp2 = tcg_temp_new_i64(); - - tcg_gen_extu_i32_i64(tmp1, a); - tcg_gen_extu_i32_i64(tmp2, b); - tcg_gen_mul_i64(tmp1, tmp1, tmp2); - tcg_temp_free_i64(tmp2); - tcg_gen_trunc_i64_i32(a, tmp1); - tcg_gen_shri_i64(tmp1, tmp1, 32); - tcg_gen_trunc_i64_i32(b, tmp1); - tcg_temp_free_i64(tmp1); -} - /* Signed 32x32->64 multiply. */ static void gen_imull(TCGv a, TCGv b) { @@ -8358,7 +8342,7 @@ static void disas_thumb_insn(CPUState *env, DisasContext *s) gen_logic_CC(tmp); break; case 0xd: /* mul */ - gen_mull(tmp, tmp2); + tcg_gen_mul_i32(tmp, tmp, tmp2); if (!s->condexec_mask) gen_logic_CC(tmp);
Current implementation of thumb mul instruction is implemented as a 32x32->64 multiply which then uses only 32 least significant bits of the result. Replace that with a simple 32x32->32 multiply. Signed-off-by: Juha Riihimäki <juha.riihimaki@nokia.com> --- break;