| Message ID | 20220805141522.412864-3-lucas.araujo@eldorado.org.br (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Floating-point OE/UE exception bug | expand |
On 8/5/22 07:15, Lucas Mateus Castro(alqotel) wrote: > From: "Lucas Mateus Castro (alqotel)" <lucas.araujo@eldorado.org.br> > > When an overflow exception occurs and OE is set the intermediate result > should be adjusted (by subtracting from the exponent) to avoid rounding > to inf. The same applies to an underflow exceptionion and UE (but adding > to the exponent). To do this set the fp_status.rebias_overflow when OE > is set and fp_status.rebias_underflow when UE is set as the FPU will > recalculate in case of a overflow/underflow if the according rebias* is > set. > > Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br> > --- > target/ppc/cpu.c | 2 ++ > target/ppc/fpu_helper.c | 2 -- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c > index 401b6f9e63..0ebac04bc4 100644 > --- a/target/ppc/cpu.c > +++ b/target/ppc/cpu.c > @@ -120,6 +120,8 @@ void ppc_store_fpscr(CPUPPCState *env, target_ulong val) > val |= FP_FEX; > } > env->fpscr = val; > + env->fp_status.rebias_overflow = (FP_OE & env->fpscr) ? true : false; > + env->fp_status.rebias_underflow = (FP_UE & env->fpscr) ? true : false; No point in the ?: operator. Otherwise, Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~ > if (tcg_enabled()) { > fpscr_set_rounding_mode(env); > } > diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c > index 134804628b..c17575de5d 100644 > --- a/target/ppc/fpu_helper.c > +++ b/target/ppc/fpu_helper.c > @@ -344,7 +344,6 @@ static inline int float_overflow_excp(CPUPPCState *env) > > bool overflow_enabled = !!(env->fpscr & FP_OE); > if (overflow_enabled) { > - /* XXX: should adjust the result */ > /* Update the floating-point enabled exception summary */ > env->fpscr |= FP_FEX; > /* We must update the target FPR before raising the exception */ > @@ -363,7 +362,6 @@ static inline void float_underflow_excp(CPUPPCState *env) > /* Update the floating-point exception summary */ > env->fpscr |= FP_FX; > if (env->fpscr & FP_UE) { > - /* XXX: should adjust the result */ > /* Update the floating-point enabled exception summary */ > env->fpscr |= FP_FEX; > /* We must update the target FPR before raising the exception */
On 8/5/22 14:17, Richard Henderson wrote: > On 8/5/22 07:15, Lucas Mateus Castro(alqotel) wrote: >> From: "Lucas Mateus Castro (alqotel)" <lucas.araujo@eldorado.org.br> >> >> When an overflow exception occurs and OE is set the intermediate result >> should be adjusted (by subtracting from the exponent) to avoid rounding >> to inf. The same applies to an underflow exceptionion and UE (but adding >> to the exponent). To do this set the fp_status.rebias_overflow when OE >> is set and fp_status.rebias_underflow when UE is set as the FPU will >> recalculate in case of a overflow/underflow if the according rebias* is >> set. >> >> Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br> >> --- >> target/ppc/cpu.c | 2 ++ >> target/ppc/fpu_helper.c | 2 -- >> 2 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c >> index 401b6f9e63..0ebac04bc4 100644 >> --- a/target/ppc/cpu.c >> +++ b/target/ppc/cpu.c >> @@ -120,6 +120,8 @@ void ppc_store_fpscr(CPUPPCState *env, target_ulong val) >> val |= FP_FEX; >> } >> env->fpscr = val; >> + env->fp_status.rebias_overflow = (FP_OE & env->fpscr) ? true : false; >> + env->fp_status.rebias_underflow = (FP_UE & env->fpscr) ? true : false; > > No point in the ?: operator. > > Otherwise, > Reviewed-by: Richard Henderson <richard.henderson@linaro.org> > Amended in the tree. No need to re-send. diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c index 0ebac04bc4..947a4bfe1f 100644 --- a/target/ppc/cpu.c +++ b/target/ppc/cpu.c @@ -120,8 +120,8 @@ void ppc_store_fpscr(CPUPPCState *env, target_ulong val) val |= FP_FEX; } env->fpscr = val; - env->fp_status.rebias_overflow = (FP_OE & env->fpscr) ? true : false; - env->fp_status.rebias_underflow = (FP_UE & env->fpscr) ? true : false; + env->fp_status.rebias_overflow = FP_OE & env->fpscr; + env->fp_status.rebias_underflow = FP_UE & env->fpscr; if (tcg_enabled()) { fpscr_set_rounding_mode(env); } Thanks, Daniel > > r~ > >> if (tcg_enabled()) { >> fpscr_set_rounding_mode(env); >> } >> diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c >> index 134804628b..c17575de5d 100644 >> --- a/target/ppc/fpu_helper.c >> +++ b/target/ppc/fpu_helper.c >> @@ -344,7 +344,6 @@ static inline int float_overflow_excp(CPUPPCState *env) >> bool overflow_enabled = !!(env->fpscr & FP_OE); >> if (overflow_enabled) { >> - /* XXX: should adjust the result */ >> /* Update the floating-point enabled exception summary */ >> env->fpscr |= FP_FEX; >> /* We must update the target FPR before raising the exception */ >> @@ -363,7 +362,6 @@ static inline void float_underflow_excp(CPUPPCState *env) >> /* Update the floating-point exception summary */ >> env->fpscr |= FP_FX; >> if (env->fpscr & FP_UE) { >> - /* XXX: should adjust the result */ >> /* Update the floating-point enabled exception summary */ >> env->fpscr |= FP_FEX; >> /* We must update the target FPR before raising the exception */ >
diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c index 401b6f9e63..0ebac04bc4 100644 --- a/target/ppc/cpu.c +++ b/target/ppc/cpu.c @@ -120,6 +120,8 @@ void ppc_store_fpscr(CPUPPCState *env, target_ulong val) val |= FP_FEX; } env->fpscr = val; + env->fp_status.rebias_overflow = (FP_OE & env->fpscr) ? true : false; + env->fp_status.rebias_underflow = (FP_UE & env->fpscr) ? true : false; if (tcg_enabled()) { fpscr_set_rounding_mode(env); } diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index 134804628b..c17575de5d 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -344,7 +344,6 @@ static inline int float_overflow_excp(CPUPPCState *env) bool overflow_enabled = !!(env->fpscr & FP_OE); if (overflow_enabled) { - /* XXX: should adjust the result */ /* Update the floating-point enabled exception summary */ env->fpscr |= FP_FEX; /* We must update the target FPR before raising the exception */ @@ -363,7 +362,6 @@ static inline void float_underflow_excp(CPUPPCState *env) /* Update the floating-point exception summary */ env->fpscr |= FP_FX; if (env->fpscr & FP_UE) { - /* XXX: should adjust the result */ /* Update the floating-point enabled exception summary */ env->fpscr |= FP_FEX; /* We must update the target FPR before raising the exception */