Byteswapping each halfword is a common operation, so extract to a new tcg_gen_hrev32_i32() generic helper.
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org> --- docs/devel/tcg-ops.rst | 4 ++++ include/tcg/tcg-op-common.h | 1 + tcg/tcg-op.c | 29 +++++++++++++++++++++++------ 3 files changed, 28 insertions(+), 6 deletions(-) diff --git a/docs/devel/tcg-ops.rst b/docs/devel/tcg-ops.rst index 7ea6aba502..17965faa03 100644 --- a/docs/devel/tcg-ops.rst +++ b/docs/devel/tcg-ops.rst @@ -490,6 +490,10 @@ Misc into 32-bit output *t0*. Depending on the host, this may be a simple shift, or may require additional canonicalization. + * - hrev32_i32 *t0*, *t1* + + - | Byteswap each halfword within a 32-bit value. + * - hswap_i32/i64 *t0*, *t1* - | Swap 16-bit halfwords within a 32/64-bit value. diff --git a/include/tcg/tcg-op-common.h b/include/tcg/tcg-op-common.h index be382bbf77..bb515dfd51 100644 --- a/include/tcg/tcg-op-common.h +++ b/include/tcg/tcg-op-common.h @@ -360,6 +360,7 @@ void tcg_gen_ext16u_i32(TCGv_i32 ret, TCGv_i32 arg); void tcg_gen_bswap16_i32(TCGv_i32 ret, TCGv_i32 arg, int flags); void tcg_gen_bswap32_i32(TCGv_i32 ret, TCGv_i32 arg); void tcg_gen_hswap_i32(TCGv_i32 ret, TCGv_i32 arg); +void tcg_gen_hrev32_i32(TCGv_i32 ret, TCGv_i32 arg); void tcg_gen_smin_i32(TCGv_i32, TCGv_i32 arg1, TCGv_i32 arg2); void tcg_gen_smax_i32(TCGv_i32, TCGv_i32 arg1, TCGv_i32 arg2); void tcg_gen_umin_i32(TCGv_i32, TCGv_i32 arg1, TCGv_i32 arg2); diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c index c436c5e263..b1b5d9b45b 100644 --- a/tcg/tcg-op.c +++ b/tcg/tcg-op.c @@ -1073,14 +1073,9 @@ void tcg_gen_bswap32_i32(TCGv_i32 ret, TCGv_i32 arg) } else { TCGv_i32 t0 = tcg_temp_ebb_new_i32(); TCGv_i32 t1 = tcg_temp_ebb_new_i32(); - TCGv_i32 t2 = tcg_constant_i32(0x00ff00ff); /* arg = abcd */ - tcg_gen_shri_i32(t0, arg, 8); /* t0 = .abc */ - tcg_gen_and_i32(t1, arg, t2); /* t1 = .b.d */ - tcg_gen_and_i32(t0, t0, t2); /* t0 = .a.c */ - tcg_gen_shli_i32(t1, t1, 8); /* t1 = b.d. */ - tcg_gen_or_i32(ret, t0, t1); /* ret = badc */ + tcg_gen_hrev32_i32(ret, arg); /* ret = badc */ tcg_gen_shri_i32(t0, ret, 16); /* t0 = ..ba */ tcg_gen_shli_i32(t1, ret, 16); /* t1 = dc.. */ @@ -1102,6 +1097,28 @@ void tcg_gen_hswap_i32(TCGv_i32 ret, TCGv_i32 arg) tcg_gen_rotli_i32(ret, arg, 16); } +/* + * hswap_i32: Byteswap each halfword within a 32-bit value. + * + * Byte pattern: hswap_i32(abcd) -> badc + */ +void tcg_gen_hrev32_i32(TCGv_i32 ret, TCGv_i32 arg) +{ + TCGv_i32 mask = tcg_constant_i32(0x00ff00ff); + TCGv_i32 t0 = tcg_temp_ebb_new_i32(); + TCGv_i32 t1 = tcg_temp_ebb_new_i32(); + + /* arg = abcd */ + tcg_gen_shri_i32(t0, arg, 8); /* t0 = .abc */ + tcg_gen_and_i32(t1, arg, mask); /* t1 = .b.d */ + tcg_gen_and_i32(t0, t0, mask); /* t0 = .a.c */ + tcg_gen_shli_i32(t1, t1, 8); /* t1 = b.d. */ + tcg_gen_or_i32(ret, t0, t1); /* ret = badc */ + + tcg_temp_free_i32(t0); + tcg_temp_free_i32(t1); +} + void tcg_gen_smin_i32(TCGv_i32 ret, TCGv_i32 a, TCGv_i32 b) { tcg_gen_movcond_i32(TCG_COND_LT, ret, a, b, a, b); -- 2.41.0