Re: [PATCH 00/12] tcg: Factor hrev{32,64}_{i32,i64,tl} out

[Nicholas Piggin]

On Tue Aug 22, 2023 at 10:40 PM AEST, Philippe Mathieu-Daudé wrote:
> This series factor the "byteswap each halfword within a
> 32/64-bit value" code duplication as generic helpers.
>
> Modulo the documentation added, there is a good negative
> diff-stat, so I believe this is a win from a maintainance
> point of view.
>
> I used "hrev" to follow the other bswap/hswap/rev helpers
> but it isn't very descriptive, so any better name suggestion
> is welcomed.
> (In particular because there are other patterns I'd like to
> factor out and then naming is getting worse, such 'wrev').

I know bswap has alrady precedent, but you could drop the bit
size when it matches the operand size, hrev_i64.

Could possibly also follow ppc and call it brevh, which tells
you the units being swapped and the size they are swapped in.
Then you could add brevw or hrevw etc. and it might be a bit
less ambiguous.

Looks like a nice cleanup though.

Thanks,
Nick

>
> Philippe Mathieu-Daudé (12):
>   tcg/tcg-op: Factor tcg_gen_hrev32_i32() out
>   target/arm: Use generic hrev32_i32() in ARM REV16 and VREV16 opcodes
>   target/cris: Use generic hrev32_i32() in SWAPB opcode
>   target/rx: Use generic hrev32_i32() in REVW opcode
>   tcg/tcg-op: Factor tcg_gen_hrev64_i64() out
>   target/mips: Use generic hrev64_i64() in DSBH opcode
>   target/ppc: Use generic hrev64_i64() in BRH / BSWAP16x8 opcodes
>   target/loongarch: Use generic hrev64_i64() in REVB.4H opcode
>   tcg/tcg-op: Add tcg_gen_hrev32_i64() and tcg_gen_hrev_i64()
>   target/arm: Use generic hrev_i64() in Aarch64 REV16 opcode
>   target/loongarch: Use generic hrev64_i32() in REVB.2H opcode
>   target/mips: Use generic hrev32_tl() in WSBH opcode
>
>  docs/devel/tcg-ops.rst                      | 10 +++
>  include/tcg/tcg-op-common.h                 |  4 +
>  include/tcg/tcg-op.h                        |  2 +
>  target/arm/tcg/translate-a32.h              |  1 -
>  target/arm/tcg/translate-a64.c              | 11 +--
>  target/arm/tcg/translate-neon.c             |  2 +-
>  target/arm/tcg/translate.c                  | 14 +---
>  target/cris/translate.c                     | 20 +----
>  target/mips/tcg/translate.c                 | 24 +-----
>  target/ppc/translate.c                      | 10 +--
>  target/rx/translate.c                       |  8 +-
>  tcg/tcg-op.c                                | 81 ++++++++++++++++++---
>  target/cris/translate_v10.c.inc             |  2 +-
>  target/loongarch/insn_trans/trans_bit.c.inc | 30 +-------
>  target/ppc/translate/vsx-impl.c.inc         | 19 +----
>  15 files changed, 99 insertions(+), 139 deletions(-)