Re: [PATCH for-8.1] accel/tcg: Zero-pad PC in TCG CPU exec trace lines

[Anton Johansson]

> In commit f0a08b0913befbd we changed the type of the PC from
> target_ulong to vaddr.  In doing so we inadvertently dropped the
> zero-padding on the PC in trace lines (the second item inside the []
> in these lines).  They used to look like this on AArch64, for
> instance:
>
> Trace 0: 0x7f2260000100 [00000000/0000000040000000/00000061/ff200000]
>
> and now they look like this:
> Trace 0: 0x7f4f50000100 [00000000/40000000/00000061/ff200000]
>
> and if the PC happens to be somewhere low like 0x5000
> then the field is shown as /5000/.
>
> This is because TARGET_FMT_lx is a "%08x" or "%016x" specifier,
> depending on TARGET_LONG_SIZE, whereas VADDR_PRIx is just PRIx64
> with no width specifier.
>
> Restore the zero-padding by adding an 016 width specifier to
> this tracing and a couple of others that were similarly recently
> changed to use VADDR_PRIx without a width specifier.
>
> We can't unfortunately restore the "32-bit guests are padded to
> 8 hex digits and 64-bit guests to 16 hex digits" behaviour so
> easily.
>
> Fixes: f0a08b0913befbd ("accel/tcg/cpu-exec.c: Widen pc to vaddr")
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> I have a workflow that parses log files to get the executed
> PC values; I don't suppose I'm the only one doing that...
> ---
>   accel/tcg/cpu-exec.c      | 4 ++--
>   accel/tcg/translate-all.c | 2 +-
>   2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
> index ba1890a373d..db1e82811fa 100644
> --- a/accel/tcg/cpu-exec.c
> +++ b/accel/tcg/cpu-exec.c
> @@ -298,7 +298,7 @@ static void log_cpu_exec(vaddr pc, CPUState *cpu,
>       if (qemu_log_in_addr_range(pc)) {
>           qemu_log_mask(CPU_LOG_EXEC,
>                         "Trace %d: %p [%08" PRIx64
> -                      "/%" VADDR_PRIx "/%08x/%08x] %s\n",
> +                      "/%016" VADDR_PRIx "/%08x/%08x] %s\n",
>                         cpu->cpu_index, tb->tc.ptr, tb->cs_base, pc,
>                         tb->flags, tb->cflags, lookup_symbol(pc));
>   
> @@ -487,7 +487,7 @@ cpu_tb_exec(CPUState *cpu, TranslationBlock *itb, int *tb_exit)
>           if (qemu_loglevel_mask(CPU_LOG_EXEC)) {
>               vaddr pc = log_pc(cpu, last_tb);
>               if (qemu_log_in_addr_range(pc)) {
> -                qemu_log("Stopped execution of TB chain before %p [%"
> +                qemu_log("Stopped execution of TB chain before %p [%016"
>                            VADDR_PRIx "] %s\n",
>                            last_tb->tc.ptr, pc, lookup_symbol(pc));
>               }
> diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> index d3d4fbc1a41..bb225afa04f 100644
> --- a/accel/tcg/translate-all.c
> +++ b/accel/tcg/translate-all.c
> @@ -604,7 +604,7 @@ void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr)
>       if (qemu_loglevel_mask(CPU_LOG_EXEC)) {
>           vaddr pc = log_pc(cpu, tb);
>           if (qemu_log_in_addr_range(pc)) {
> -            qemu_log("cpu_io_recompile: rewound execution of TB to %"
> +            qemu_log("cpu_io_recompile: rewound execution of TB to %016"
>                        VADDR_PRIx "\n", pc);
>           }
>       }
This was definitely a mistake on my part, thanks for the quick fix!

Reviewed-by: Anton Johansson <anjo@rev.ng>