Re: [Qemu-devel] [PATCH v2 1/3] softmmu: add helper function to pass through retaddr

["Pavel Dovgaluk" <Pavel.Dovgaluk@ispras.ru>]

> From: Paolo Bonzini [mailto:pbonzini@redhat.com]
> On 17/06/2015 14:42, Pavel Dovgalyuk wrote:
> > This patch introduces several helpers to pass return address
> > which points to the TB. Correct return address allows correct
> > restoring of the guest PC and icount. These functions should be used when
> > helpers embedded into TB invoke memory operations.
> >
> > Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
> > ---
> >  include/exec/cpu_ldst_template.h |   42 +++++++++++++++++++++++++++++++-------
> >  include/exec/exec-all.h          |   27 ++++++++++++++++++++++++
> >  softmmu_template.h               |   18 ++++++++++++++++
> >  3 files changed, 79 insertions(+), 8 deletions(-)
> >
> > diff --git a/include/exec/cpu_ldst_template.h b/include/exec/cpu_ldst_template.h
> > index 95ab750..1847816 100644
> > --- a/include/exec/cpu_ldst_template.h
> > +++ b/include/exec/cpu_ldst_template.h
> > @@ -62,7 +62,9 @@
> >  /* generic load/store macros */
> >
> >  static inline RES_TYPE
> > -glue(glue(cpu_ld, USUFFIX), MEMSUFFIX)(CPUArchState *env, target_ulong ptr)
> > +glue(glue(glue(cpu_ld, USUFFIX), MEMSUFFIX), _ra)(CPUArchState *env,
> > +                                                  target_ulong ptr,
> > +                                                  uintptr_t retaddr)
> 
> Would it make sense to call these helper_cpu_ld##USUFFIX##MEMSUFFIX?
> 
> > diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
> > index 856e698..b3aefde 100644
> > --- a/include/exec/exec-all.h
> > +++ b/include/exec/exec-all.h
> > @@ -350,6 +350,33 @@ struct MemoryRegion *iotlb_to_region(CPUState *cpu,
> >  void tlb_fill(CPUState *cpu, target_ulong addr, int is_write, int mmu_idx,
> >                uintptr_t retaddr);
> >
> > +uint8_t helper_call_ldb_cmmu(CPUArchState *env, target_ulong addr,
> > +                             int mmu_idx, uintptr_t retaddr);
> 
> Here we already have helper_ret_ldb_cmmu, so the new function is only
> needed if DATA_SIZE != 1.
> 
> > +uint16_t helper_call_ldw_cmmu(CPUArchState *env, target_ulong addr,
> > +                              int mmu_idx, uintptr_t retaddr);
> 
> What about helper_ret_ldw_cmmu for consistency with the DATA_SIZE == 1 case?

tcg.h breaks these definitions:

/* Temporary aliases until backends are converted.  */
#ifdef TARGET_WORDS_BIGENDIAN
# define helper_ret_ldsw_mmu  helper_be_ldsw_mmu
# define helper_ret_lduw_mmu  helper_be_lduw_mmu
# define helper_ret_ldsl_mmu  helper_be_ldsl_mmu
# define helper_ret_ldul_mmu  helper_be_ldul_mmu
# define helper_ret_ldq_mmu   helper_be_ldq_mmu
# define helper_ret_stw_mmu   helper_be_stw_mmu
# define helper_ret_stl_mmu   helper_be_stl_mmu
# define helper_ret_stq_mmu   helper_be_stq_mmu
#else

Pavel Dovgalyuk