diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2021-06-13 16:27:18 +0000 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2021-06-29 10:04:57 -0700 |
| commit | 8a611d8640c0a2d09fd3ca7af893230fe124bdc5 (patch) | |
| tree | 6801e1af03f065ed8ca67220dd8c46e38d9cea59 /tcg/ppc | |
| parent | 783d3ecdda97f0f332afa9de1cfa6fac100db31c (diff) | |
tcg/ppc: Split out tcg_out_bswap32
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'tcg/ppc')
| -rw-r--r-- | tcg/ppc/tcg-target.c.inc | 38 |
1 files changed, 22 insertions, 16 deletions
diff --git a/tcg/ppc/tcg-target.c.inc b/tcg/ppc/tcg-target.c.inc index ad46ce32ca..28b8671cba 100644 --- a/tcg/ppc/tcg-target.c.inc +++ b/tcg/ppc/tcg-target.c.inc @@ -807,6 +807,27 @@ static void tcg_out_bswap16(TCGContext *s, TCGReg dst, TCGReg src) tcg_out_mov(s, TCG_TYPE_REG, dst, tmp); } +static void tcg_out_bswap32(TCGContext *s, TCGReg dst, TCGReg src) +{ + TCGReg tmp = dst == src ? TCG_REG_R0 : dst; + + /* + * Stolen from gcc's builtin_bswap32. + * In the following, + * dep(a, b, m) -> (a & ~m) | (b & m) + * + * Begin with: src = xxxxabcd + */ + /* tmp = rol32(src, 8) & 0xffffffff = 0000bcda */ + tcg_out_rlw(s, RLWINM, tmp, src, 8, 0, 31); + /* tmp = dep(tmp, rol32(src, 24), 0xff000000) = 0000dcda */ + tcg_out_rlw(s, RLWIMI, tmp, src, 24, 0, 7); + /* tmp = dep(tmp, rol32(src, 24), 0x0000ff00) = 0000dcba */ + tcg_out_rlw(s, RLWIMI, tmp, src, 24, 16, 23); + + tcg_out_mov(s, TCG_TYPE_REG, dst, tmp); +} + /* Emit a move into ret of arg, if it can be done in one insn. */ static bool tcg_out_movi_one(TCGContext *s, TCGReg ret, tcg_target_long arg) { @@ -2799,24 +2820,9 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, case INDEX_op_bswap16_i64: tcg_out_bswap16(s, args[0], args[1]); break; - case INDEX_op_bswap32_i32: case INDEX_op_bswap32_i64: - /* Stolen from gcc's builtin_bswap32 */ - a1 = args[1]; - a0 = args[0] == a1 ? TCG_REG_R0 : args[0]; - - /* a1 = args[1] # abcd */ - /* a0 = rotate_left (a1, 8) # bcda */ - tcg_out_rlw(s, RLWINM, a0, a1, 8, 0, 31); - /* a0 = (a0 & ~0xff000000) | ((a1 r<< 24) & 0xff000000) # dcda */ - tcg_out_rlw(s, RLWIMI, a0, a1, 24, 0, 7); - /* a0 = (a0 & ~0x0000ff00) | ((a1 r<< 24) & 0x0000ff00) # dcba */ - tcg_out_rlw(s, RLWIMI, a0, a1, 24, 16, 23); - - if (a0 == TCG_REG_R0) { - tcg_out_mov(s, TCG_TYPE_REG, args[0], a0); - } + tcg_out_bswap32(s, args[0], args[1]); break; case INDEX_op_bswap64_i64: |