| Message ID | 1375726045-20797-3-git-send-email-rth@twiddle.net |
|---|---|
| State | New |
| Headers | show |
On Mon, Aug 05, 2013 at 08:07:19AM -1000, Richard Henderson wrote: > Use a 7 byte lea before the ultimate 10 byte movq. > > Signed-off-by: Richard Henderson <rth@twiddle.net> > --- > tcg/i386/tcg-target.c | 19 ++++++++++++++++--- > 1 file changed, 16 insertions(+), 3 deletions(-) > > diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c > index 841bd75..456bd9e 100644 > --- a/tcg/i386/tcg-target.c > +++ b/tcg/i386/tcg-target.c > @@ -541,19 +541,32 @@ static inline void tcg_out_mov(TCGContext *s, TCGType type, > static void tcg_out_movi(TCGContext *s, TCGType type, > TCGReg ret, tcg_target_long arg) > { > + tcg_target_long diff; > + > if (arg == 0) { > tgen_arithr(s, ARITH_XOR, ret, ret); > return; > } else if (arg == (uint32_t)arg || type == TCG_TYPE_I32) { > tcg_out_opc(s, OPC_MOVL_Iv + LOWREGMASK(ret), 0, ret, 0); > tcg_out32(s, arg); > + return; > } else if (arg == (int32_t)arg) { > tcg_out_modrm(s, OPC_MOVL_EvIz + P_REXW, 0, ret); > tcg_out32(s, arg); > - } else { > - tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0); > - tcg_out64(s, arg); > + return; > } Now that all the else parts end up with a return, it would improve readability to remove them and keep only the ifs. > + > + /* Try a 7 byte pc-relative lea before the 10 byte movq. */ > + diff = arg - ((tcg_target_long)s->code_ptr + 7); > + if (diff == (int32_t)diff) { > + tcg_out_opc(s, OPC_LEA | P_REXW, ret, 0, 0); > + tcg_out8(s, (LOWREGMASK(ret) << 3) | 5); > + tcg_out32(s, diff); > + return; > + } > + > + tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0); > + tcg_out64(s, arg); > } > > static inline void tcg_out_pushi(TCGContext *s, tcg_target_long val) Otherwise it looks good.
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c index 841bd75..456bd9e 100644 --- a/tcg/i386/tcg-target.c +++ b/tcg/i386/tcg-target.c @@ -541,19 +541,32 @@ static inline void tcg_out_mov(TCGContext *s, TCGType type, static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg ret, tcg_target_long arg) { + tcg_target_long diff; + if (arg == 0) { tgen_arithr(s, ARITH_XOR, ret, ret); return; } else if (arg == (uint32_t)arg || type == TCG_TYPE_I32) { tcg_out_opc(s, OPC_MOVL_Iv + LOWREGMASK(ret), 0, ret, 0); tcg_out32(s, arg); + return; } else if (arg == (int32_t)arg) { tcg_out_modrm(s, OPC_MOVL_EvIz + P_REXW, 0, ret); tcg_out32(s, arg); - } else { - tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0); - tcg_out64(s, arg); + return; } + + /* Try a 7 byte pc-relative lea before the 10 byte movq. */ + diff = arg - ((tcg_target_long)s->code_ptr + 7); + if (diff == (int32_t)diff) { + tcg_out_opc(s, OPC_LEA | P_REXW, ret, 0, 0); + tcg_out8(s, (LOWREGMASK(ret) << 3) | 5); + tcg_out32(s, diff); + return; + } + + tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0); + tcg_out64(s, arg); } static inline void tcg_out_pushi(TCGContext *s, tcg_target_long val)
Use a 7 byte lea before the ultimate 10 byte movq. Signed-off-by: Richard Henderson <rth@twiddle.net> --- tcg/i386/tcg-target.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-)