Re: [Qemu-devel] [PATCH v2 4/7] disas: arm: QOMify target specific disas setup

[Peter Maydell]

On 9 May 2015 at 21:11, Peter Crosthwaite <address@hidden> wrote:
> Move the target_disas() ARM specifics to the QOM disas_set_info hook
> and delete the ARM specific code in disas.c.
>
> This has the extra advantage of the more fully featured target_disas()
> implementation now applying to monitor_disas().
>
> Currently, target_disas() has multi-endian, thumb and AArch64
> support whereas the existing monitor_disas() support only has vanilla
> AA32 support.
>
> E.G. Running an AA64 linux kernel the follow -d in_asm disas happens
> (taget_disas()):
>
> IN:
> 0x0000000040000000:  580000c0      ldr x0, pc+24 (addr 0x40000018)
> 0x0000000040000004:  aa1f03e1      mov x1, xzr
>
> However before this patch, disasing the same from the monitor:
>
> (qemu) xp/i 0x40000000
> 0x0000000040000000:  580000c0      stmdapl  r0, {r6, r7}
>
> After this patch:
> (qemu) xp/i 0x40000000
> 0x0000000040000000:  580000c0      ldr x0, pc+24 (addr 0x40000018)
>
> Signed-off-by: Peter Crosthwaite <address@hidden>
> ---
>  disas.c          | 32 --------------------------------
>  target-arm/cpu.c | 35 +++++++++++++++++++++++++++++++++++
>  2 files changed, 35 insertions(+), 32 deletions(-)
>
> diff --git a/disas.c b/disas.c
> index 1d46d25..1700537 100644
> --- a/disas.c
> +++ b/disas.c
> @@ -151,14 +151,6 @@ bfd_vma bfd_getb16 (const bfd_byte *addr)
>    return (bfd_vma) v;
>  }
>
> -#ifdef TARGET_ARM
> -static int
> -print_insn_thumb1(bfd_vma pc, disassemble_info *info)
> -{
> -  return print_insn_arm(pc | 1, info);
> -}
> -#endif
> -
>  static int print_insn_objdump(bfd_vma pc, disassemble_info *info,
>                                const char *prefix)
>  {
> @@ -191,7 +183,6 @@ static int print_insn_od_target(bfd_vma pc, 
> disassemble_info *info)
>  /* Disassemble this for me please... (debugging). 'flags' has the following
>     values:
>      i386 - 1 means 16 bit code, 2 means 64 bit code
> -    arm  - bit 0 = thumb, bit 1 = reverse endian, bit 2 = A64
>      ppc  - bits 0:15 specify (optionally) the machine instruction set;
>             bit 16 indicates little endian.
>      other targets - unused
> @@ -232,27 +223,6 @@ void target_disas(FILE *out, CPUArchState *env, 
> target_ulong code,
>          s.info.mach = bfd_mach_i386_i386;
>      }
>      s.info.print_insn = print_insn_i386;
> -#elif defined(TARGET_ARM)
> -    if (flags & 4) {
> -        /* We might not be compiled with the A64 disassembler
> -         * because it needs a C++ compiler; in that case we will
> -         * fall through to the default print_insn_od case.
> -         */
> -#if defined(CONFIG_ARM_A64_DIS)
> -        s.info.print_insn = print_insn_arm_a64;
> -#endif
> -    } else if (flags & 1) {
> -        s.info.print_insn = print_insn_thumb1;
> -    } else {
> -        s.info.print_insn = print_insn_arm;
> -    }
> -    if (flags & 2) {
> -#ifdef TARGET_WORDS_BIGENDIAN
> -        s.info.endian = BFD_ENDIAN_LITTLE;
> -#else
> -        s.info.endian = BFD_ENDIAN_BIG;
> -#endif
> -    }
>  #elif defined(TARGET_SPARC)
>      s.info.print_insn = print_insn_sparc;
>  #ifdef TARGET_SPARC64
> @@ -490,8 +460,6 @@ void monitor_disas(Monitor *mon, CPUArchState *env,
>          s.info.mach = bfd_mach_i386_i386;
>      }
>      s.info.print_insn = print_insn_i386;
> -#elif defined(TARGET_ARM)
> -    s.info.print_insn = print_insn_arm;
>  #elif defined(TARGET_ALPHA)
>      s.info.print_insn = print_insn_alpha;
>  #elif defined(TARGET_SPARC)
> diff --git a/target-arm/cpu.c b/target-arm/cpu.c
> index 3ca3fa8..cfa761a 100644
> --- a/target-arm/cpu.c
> +++ b/target-arm/cpu.c
> @@ -362,6 +362,39 @@ static inline void unset_feature(CPUARMState *env, int 
> feature)
>      env->features &= ~(1ULL << feature);
>  }
>
> +static int
> +print_insn_thumb1(bfd_vma pc, disassemble_info *info)
> +{
> +  return print_insn_arm(pc | 1, info);
> +}
> +
> +static void arm_disas_set_info(CPUState *cpu, disassemble_info *info)
> +{
> +    ARMCPU *ac = ARM_CPU(cpu);
> +    CPUARMState *env = &ac->env;
> +
> +    if (env->aarch64) {

if (is_a64(env)) please.
(At some point I'm likely to tidy up handling of A64 pstate,
and maybe this flag will disappear back into the uncached pstate.)

Otherwise
Reviewed-by: Peter Maydell <address@hidden>

thanks
-- PMM