diff options
| author | Richard Henderson <rth@twiddle.net> | 2014-01-27 21:19:40 -0800 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2014-02-17 10:12:29 -0600 |
| commit | ecc7e84327c1c8e9b006edfaa5d0e3baf35a3f99 (patch) | |
| tree | e242199ebb360619264acf098dfc400b1a80e41e /tcg | |
| parent | a1b29c9ae06abe7ded354eb70767e34dc035db72 (diff) | |
| download | qemu-ecc7e84327c1c8e9b006edfaa5d0e3baf35a3f99.tar.gz | |
tcg/i386: Add tcg_out_vex_modrm
Prepare for emitting BMI insns which require VEX encoding.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg')
| -rw-r--r-- | tcg/i386/tcg-target.c | 41 |
1 files changed, 38 insertions, 3 deletions
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c index 7008b0eb7f..00dbc3b0c4 100644 --- a/tcg/i386/tcg-target.c +++ b/tcg/i386/tcg-target.c @@ -402,9 +402,9 @@ static void tcg_out_opc(TCGContext *s, int opc, int r, int rm, int x) rex = 0; rex |= (opc & P_REXW) ? 0x8 : 0x0; /* REX.W */ - rex |= (r & 8) >> 1; /* REX.R */ - rex |= (x & 8) >> 2; /* REX.X */ - rex |= (rm & 8) >> 3; /* REX.B */ + rex |= (r & 8) >> 1; /* REX.R */ + rex |= (x & 8) >> 2; /* REX.X */ + rex |= (rm & 8) >> 3; /* REX.B */ /* P_REXB_{R,RM} indicates that the given register is the low byte. For %[abcd]l we need no REX prefix, but for %{si,di,bp,sp}l we do, @@ -453,6 +453,41 @@ static void tcg_out_modrm(TCGContext *s, int opc, int r, int rm) tcg_out8(s, 0xc0 | (LOWREGMASK(r) << 3) | LOWREGMASK(rm)); } +static void tcg_out_vex_modrm(TCGContext *s, int opc, int r, int v, int rm) +{ + int tmp; + + if ((opc & (P_REXW | P_EXT | P_EXT38)) || (rm & 8)) { + /* Three byte VEX prefix. */ + tcg_out8(s, 0xc4); + + /* VEX.m-mmmm */ + if (opc & P_EXT38) { + tmp = 2; + } else if (opc & P_EXT) { + tmp = 1; + } else { + tcg_abort(); + } + tmp |= 0x40; /* VEX.X */ + tmp |= (r & 8 ? 0 : 0x80); /* VEX.R */ + tmp |= (rm & 8 ? 0 : 0x20); /* VEX.B */ + tcg_out8(s, tmp); + + tmp = (opc & P_REXW ? 0x80 : 0); /* VEX.W */ + } else { + /* Two byte VEX prefix. */ + tcg_out8(s, 0xc5); + + tmp = (r & 8 ? 0 : 0x80); /* VEX.R */ + } + tmp |= (opc & P_DATA16 ? 1 : 0); /* VEX.pp */ + tmp |= (~v & 15) << 3; /* VEX.vvvv */ + tcg_out8(s, tmp); + tcg_out8(s, opc); + tcg_out8(s, 0xc0 | (LOWREGMASK(r) << 3) | LOWREGMASK(rm)); +} + /* Output an opcode with a full "rm + (index<<shift) + offset" address mode. We handle either RM and INDEX missing with a negative value. In 64-bit mode for absolute addresses, ~RM is the size of the immediate operand |