[02/32] ppc: Provide basic raise_exception_* functions

Instead of using the same helpers called from translate.c, let's have
a bunch of functions that take the various argument combinations,
especially the retaddr which will be needed in subsequent patches,
and leave the helpers to be just that, helpers for translate.c

We don't yet convert all users, we'll go through them in subsequent
patches.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
 target-ppc/cpu.h         |  8 ++++++++
 target-ppc/excp_helper.c | 51 ++++++++++++++++++++++++++++++++----------------
 2 files changed, 42 insertions(+), 17 deletions(-)

On Wed, Jul 27, 2016 at 08:20:56AM +1000, Benjamin Herrenschmidt wrote:
> Instead of using the same helpers called from translate.c, let's have
> a bunch of functions that take the various argument combinations,
> especially the retaddr which will be needed in subsequent patches,
> and leave the helpers to be just that, helpers for translate.c
> 
> We don't yet convert all users, we'll go through them in subsequent
> patches.
> 
> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
>  target-ppc/cpu.h         |  8 ++++++++
>  target-ppc/excp_helper.c | 51 ++++++++++++++++++++++++++++++++----------------
>  2 files changed, 42 insertions(+), 17 deletions(-)
> 
> diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
> index 5fce1ff..2ee7a5e 100644
> --- a/target-ppc/cpu.h
> +++ b/target-ppc/cpu.h
> @@ -2295,6 +2295,14 @@ static inline void cpu_get_tb_cpu_state(CPUPPCState *env, target_ulong *pc,
>      *flags = env->hflags;
>  }
>  
> +void QEMU_NORETURN raise_exception(CPUPPCState *env, uint32_t exception);
> +void QEMU_NORETURN raise_exception_ra(CPUPPCState *env, uint32_t exception,
> +                                      uintptr_t raddr);
> +void QEMU_NORETURN raise_exception_err(CPUPPCState *env, uint32_t exception,
> +                                       uint32_t error_code);
> +void QEMU_NORETURN raise_exception_err_ra(CPUPPCState *env, uint32_t exception,
> +                                          uint32_t error_code, uintptr_t raddr);
> +
>  #if !defined(CONFIG_USER_ONLY)
>  static inline int booke206_tlbm_id(CPUPPCState *env, ppcmas_tlb_t *tlbm)
>  {
> diff --git a/target-ppc/excp_helper.c b/target-ppc/excp_helper.c
> index d6e1678..f4b115e 100644
> --- a/target-ppc/excp_helper.c
> +++ b/target-ppc/excp_helper.c
> @@ -898,34 +898,53 @@ static void cpu_dump_rfi(target_ulong RA, target_ulong msr)
>  /*****************************************************************************/
>  /* Exceptions processing helpers */
>  
> -void helper_raise_exception_err(CPUPPCState *env, uint32_t exception,
> -                                uint32_t error_code)
> +void raise_exception_err_ra(CPUPPCState *env, uint32_t exception,
> +                            uint32_t error_code, uintptr_t raddr)
>  {
>      CPUState *cs = CPU(ppc_env_get_cpu(env));
>  
> -#if 0
> -    printf("Raise exception %3x code : %d\n", exception, error_code);
> -#endif
>      cs->exception_index = exception;
>      env->error_code = error_code;
> -    cpu_loop_exit(cs);
> +    cpu_loop_exit_restore(cs, raddr);
> +}
> +
> +void raise_exception_err(CPUPPCState *env, uint32_t exception,
> +                         uint32_t error_code)
> +{
> +    raise_exception_err_ra(env, exception, error_code, 0);
> +}
> +
> +void raise_exception(CPUPPCState *env, uint32_t exception)
> +{
> +    raise_exception_err_ra(env, exception, 0, 0);
> +}
> +
> +void raise_exception_ra(CPUPPCState *env, uint32_t exception,
> +                        uintptr_t raddr)
> +{
> +    raise_exception_err_ra(env, exception, 0, 0);

This should pass raddr as the last argument, shouldn't it?

> +}
> +
> +void helper_raise_exception_err(CPUPPCState *env, uint32_t exception,
> +                                uint32_t error_code)
> +{
> +    raise_exception_err_ra(env, exception, error_code, 0);
>  }
>  
>  void helper_raise_exception(CPUPPCState *env, uint32_t exception)
>  {
> -    helper_raise_exception_err(env, exception, 0);
> +    raise_exception_err_ra(env, exception, 0, 0);
>  }
>  
>  #if !defined(CONFIG_USER_ONLY)
>  void helper_store_msr(CPUPPCState *env, target_ulong val)
>  {
> -    CPUState *cs;
> +    uint32_t excp = hreg_store_msr(env, val, 0);
>  
> -    val = hreg_store_msr(env, val, 0);
> -    if (val != 0) {
> -        cs = CPU(ppc_env_get_cpu(env));
> +    if (excp != 0) {
> +        CPUState *cs = CPU(ppc_env_get_cpu(env));
>          cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
> -        helper_raise_exception(env, val);
> +        raise_exception(env, excp);
>      }
>  }
>  
> @@ -951,7 +970,7 @@ void helper_pminsn(CPUPPCState *env, powerpc_pm_insn_t insn)
>       * but this doesn't seem to be a problem.
>       */
>      env->msr |= (1ull << MSR_EE);
> -    helper_raise_exception(env, EXCP_HLT);
> +    raise_exception(env, EXCP_HLT);
>  }
>  #endif /* defined(TARGET_PPC64) */
>  
> @@ -1041,8 +1060,7 @@ void helper_tw(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
>                    ((int32_t)arg1 == (int32_t)arg2 && (flags & 0x04)) ||
>                    ((uint32_t)arg1 < (uint32_t)arg2 && (flags & 0x02)) ||
>                    ((uint32_t)arg1 > (uint32_t)arg2 && (flags & 0x01))))) {
> -        helper_raise_exception_err(env, POWERPC_EXCP_PROGRAM,
> -                                   POWERPC_EXCP_TRAP);
> +        raise_exception_err(env, POWERPC_EXCP_PROGRAM, POWERPC_EXCP_TRAP);
>      }
>  }
>  
> @@ -1055,8 +1073,7 @@ void helper_td(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
>                    ((int64_t)arg1 == (int64_t)arg2 && (flags & 0x04)) ||
>                    ((uint64_t)arg1 < (uint64_t)arg2 && (flags & 0x02)) ||
>                    ((uint64_t)arg1 > (uint64_t)arg2 && (flags & 0x01))))) {
> -        helper_raise_exception_err(env, POWERPC_EXCP_PROGRAM,
> -                                   POWERPC_EXCP_TRAP);
> +        raise_exception_err(env, POWERPC_EXCP_PROGRAM, POWERPC_EXCP_TRAP);
>      }
>  }
>  #endif

On Wed, 2016-07-27 at 11:50 +1000, David Gibson wrote:
> 

> > +void raise_exception_err(CPUPPCState *env, uint32_t exception,

> > +                         uint32_t error_code)

> > +{

> > +    raise_exception_err_ra(env, exception, error_code, 0);

> > +}

> > +

> > +void raise_exception(CPUPPCState *env, uint32_t exception)

> > +{

> > +    raise_exception_err_ra(env, exception, 0, 0);

> > +}

> > +

> > +void raise_exception_ra(CPUPPCState *env, uint32_t exception,

> > +                        uintptr_t raddr)

> > +{

> > +    raise_exception_err_ra(env, exception, 0, 0);

> 

> This should pass raddr as the last argument, shouldn't it?


Yes. The fact that I didn't notice the breakage shows how few things
actually care about those exceptions being precise ;-) I'll respin the
patch. Thanks.

Cheers,
Ben.