Re: [PATCH] tcg: Remove unused tcg_out_dupi_vec() stub

[Wataru Ashihara]

Philippe, Richard, thank you for reviewing.

On 2021/01/11 1:17, Philippe Mathieu-Daudé wrote:
> Cc'ing Stefan.
> 
> On 1/10/21 5:10 AM, Wataru Ashihara wrote:
>> This fixes the build with --enable-tcg-interpreter:
>>
>>   clang -Ilibqemu-arm-softmmu.fa.p -I. -I.. -Itarget/arm -I../target/arm 
>> -I../dtc/libfdt -I../capstone/include/capstone -Iqapi -Itrace -Iui 
>> -Iui/shader -I/usr/include/pixman-1 -I/usr/include/glib-2.0 
>> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -Xclang -fcolor-diagnostics 
>> -pipe -Wall -Winvalid-pch -Werror -std=gnu99 -g -m64 -mcx16 -D_GNU_SOURCE 
>> -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes 
>> -Wredundant-decls -Wundef -Wwrite-strings -Wmissing-prototypes 
>> -fno-strict-aliasing -fno-common -fwrapv -Wold-style-definition 
>> -Wtype-limits -Wformat-security -Wformat-y2k -Winit-self 
>> -Wignored-qualifiers -Wempty-body -Wnested-externs -Wendif-labels 
>> -Wexpansion-to-defined -Wno-initializer-overrides -Wno-missing-include-dirs 
>> -Wno-shift-negative-value -Wno-string-plus-int -Wno-typedef-redefinition 
>> -Wno-tautological-type-limit-compare -fstack-protector-strong -isystem 
>> /home/wsh/qc/qemu/linux-headers -isystem linux-headers -iquote 
>> /home/wsh/qc/qemu/tcg/tci -iquote . -iquote /home/wsh/qc/qemu -iquote 
>> /home/wsh/qc/qemu/accel/tcg -iquote /home/wsh/qc/qemu/include -iquote 
>> /home/wsh/qc/qemu/disas/libvixl -pthread -fPIC -isystem../linux-headers 
>> -isystemlinux-headers -DNEED_CPU_H 
>> '-DCONFIG_TARGET="arm-softmmu-config-target.h"' 
>> '-DCONFIG_DEVICES="arm-softmmu-config-devices.h"' -MD -MQ 
>> libqemu-arm-softmmu.fa.p/tcg_tcg.c.o -MF 
>> libqemu-arm-softmmu.fa.p/tcg_tcg.c.o.d -o 
>> libqemu-arm-softmmu.fa.p/tcg_tcg.c.o -c ../tcg/tcg.c
>>   ../tcg/tcg.c:136:20: error: unused function 'tcg_out_dupi_vec' 
>> [-Werror,-Wunused-function]
>>
>> Signed-off-by: Wataru Ashihara <wataash@wataash.com>
>> ---
>>  tcg/tcg.c | 7 -------
>>  1 file changed, 7 deletions(-)
>>
>> diff --git a/tcg/tcg.c b/tcg/tcg.c
>> index 472bf1755b..32df149b12 100644
>> --- a/tcg/tcg.c
>> +++ b/tcg/tcg.c
>> @@ -117,8 +117,6 @@ static bool tcg_out_dup_vec(TCGContext *s, TCGType type, 
>> unsigned vece,
>>                              TCGReg dst, TCGReg src);
>>  static bool tcg_out_dupm_vec(TCGContext *s, TCGType type, unsigned vece,
>>                               TCGReg dst, TCGReg base, intptr_t offset);
>> -static void tcg_out_dupi_vec(TCGContext *s, TCGType type,
>> -                             TCGReg dst, tcg_target_long arg);
>>  static void tcg_out_vec_op(TCGContext *s, TCGOpcode opc, unsigned vecl,
>>                             unsigned vece, const TCGArg *args,
>>                             const int *const_args);
>> @@ -133,11 +131,6 @@ static inline bool tcg_out_dupm_vec(TCGContext *s, 
>> TCGType type, unsigned vece,
>>  {
>>      g_assert_not_reached();
>>  }
>> -static inline void tcg_out_dupi_vec(TCGContext *s, TCGType type,
>> -                                    TCGReg dst, tcg_target_long arg)
>> -{
>> -    g_assert_not_reached();
>> -}
>>  static inline void tcg_out_vec_op(TCGContext *s, TCGOpcode opc, unsigned 
>> vecl,
>>                                    unsigned vece, const TCGArg *args,
>>                                    const int *const_args)
> 
> AFAIK TCI does not support vectors, using them would trigger
> tcg_debug_assert(type == TCG_TYPE_I64) in tcg_out_movi().
> 
> As your approach might break other backends, I'm going to
> send an alternate patch using __attribute__((unused)).

Currently it doesn't. Unlike all the other tcg_out_*(),
tcg_out_dupi_vec() is not used in tcg.c as discussed in [1].

> 
> Thanks for reporting this,
> 
> Phil.
> 

I discard this patch in favor of the unconditionally-using way mentioned
in [1].

Thanks.

[1]: https://lists.nongnu.org/archive/html/qemu-devel/2021-01/msg01647.html