| Message ID | 20210614083800.1166166-7-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tcg: bswap improvements | expand |
On Mon, 14 Jun 2021 at 09:43, Richard Henderson <richard.henderson@linaro.org> wrote: > > We will shortly require sari in other context; > split out both for cleanliness sake. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > tcg/ppc/tcg-target.c.inc | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > /* Limit immediate shift count lest we create an illegal insn. */ > - tcg_out32(s, SRAWI | RS(args[1]) | RA(args[0]) | SH(args[2] & 31)); > + tcg_out_sari32(s, args[0], args[1], args[2] & 31); Maybe the "& 31" would be better inside tcg_out_sari32() rather than outside it? The sari64() implementation already implicitly ignores high bits of an overlarge shift count, so having sari32() do the same would be more consistent. Either way Reviewed-by: Peter Maydell <peter.maydell@linaro.org> thanks -- PMM
On 6/21/21 7:22 AM, Peter Maydell wrote: > On Mon, 14 Jun 2021 at 09:43, Richard Henderson > <richard.henderson@linaro.org> wrote: >> >> We will shortly require sari in other context; >> split out both for cleanliness sake. >> >> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> >> --- >> tcg/ppc/tcg-target.c.inc | 15 ++++++++++++--- >> 1 file changed, 12 insertions(+), 3 deletions(-) > >> /* Limit immediate shift count lest we create an illegal insn. */ >> - tcg_out32(s, SRAWI | RS(args[1]) | RA(args[0]) | SH(args[2] & 31)); >> + tcg_out_sari32(s, args[0], args[1], args[2] & 31); > > Maybe the "& 31" would be better inside tcg_out_sari32() > rather than outside it? The sari64() implementation already > implicitly ignores high bits of an overlarge shift count, so > having sari32() do the same would be more consistent. > > Either way > Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Good idea. r~
diff --git a/tcg/ppc/tcg-target.c.inc b/tcg/ppc/tcg-target.c.inc index aa35ff8250..b49204f707 100644 --- a/tcg/ppc/tcg-target.c.inc +++ b/tcg/ppc/tcg-target.c.inc @@ -768,6 +768,11 @@ static inline void tcg_out_shli64(TCGContext *s, TCGReg dst, TCGReg src, int c) tcg_out_rld(s, RLDICR, dst, src, c, 63 - c); } +static inline void tcg_out_sari32(TCGContext *s, TCGReg dst, TCGReg src, int c) +{ + tcg_out32(s, SRAWI | RA(dst) | RS(src) | SH(c)); +} + static inline void tcg_out_shri32(TCGContext *s, TCGReg dst, TCGReg src, int c) { tcg_out_rlw(s, RLWINM, dst, src, 32 - c, c, 31); @@ -778,6 +783,11 @@ static inline void tcg_out_shri64(TCGContext *s, TCGReg dst, TCGReg src, int c) tcg_out_rld(s, RLDICL, dst, src, 64 - c, c); } +static inline void tcg_out_sari64(TCGContext *s, TCGReg dst, TCGReg src, int c) +{ + tcg_out32(s, SRADI | RA(dst) | RS(src) | SH(c & 0x1f) | ((c >> 4) & 2)); +} + /* 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) { @@ -2602,7 +2612,7 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, case INDEX_op_sar_i32: if (const_args[2]) { /* Limit immediate shift count lest we create an illegal insn. */ - tcg_out32(s, SRAWI | RS(args[1]) | RA(args[0]) | SH(args[2] & 31)); + tcg_out_sari32(s, args[0], args[1], args[2] & 31); } else { tcg_out32(s, SRAW | SAB(args[1], args[0], args[2])); } @@ -2690,8 +2700,7 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, break; case INDEX_op_sar_i64: if (const_args[2]) { - int sh = SH(args[2] & 0x1f) | (((args[2] >> 5) & 1) << 1); - tcg_out32(s, SRADI | RA(args[0]) | RS(args[1]) | sh); + tcg_out_sari64(s, args[0], args[1], args[2]); } else { tcg_out32(s, SRAD | SAB(args[1], args[0], args[2])); }
We will shortly require sari in other context; split out both for cleanliness sake. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- tcg/ppc/tcg-target.c.inc | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) -- 2.25.1