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| author | Richard Henderson <rth@twiddle.net> | 2010-01-05 16:03:00 -0800 |
|---|---|---|
| committer | Aurelien Jarno <aurelien@aurel32.net> | 2010-01-14 18:16:40 +0100 |
| commit | 5716990376e22e758c434ba7092b8eacaa148973 (patch) | |
| tree | 225bf78c92e97d0c7016f76f2ba54e42c3fc4171 /tcg | |
| parent | 0a4e7cd2374f1d898a25f4ae7d0fb0321433c197 (diff) | |
| download | qemu-5716990376e22e758c434ba7092b8eacaa148973.tar.gz qemu-5716990376e22e758c434ba7092b8eacaa148973.tar.bz2 qemu-5716990376e22e758c434ba7092b8eacaa148973.zip | |
tcg/x86_64: Special-case all 32-bit AND operands.
This avoids an unnecessary REX.W prefix when dealing with AND
operands that fit into a 32-bit quantity. The most common change
actually seen is movz[wb]q -> movz[wb]l.
Similarly, avoid REXW in ext{8,16}u_i64 tcg opcodes.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Diffstat (limited to 'tcg')
| -rw-r--r-- | tcg/x86_64/tcg-target.c | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/tcg/x86_64/tcg-target.c b/tcg/x86_64/tcg-target.c index 23390914d2..8c7e738180 100644 --- a/tcg/x86_64/tcg-target.c +++ b/tcg/x86_64/tcg-target.c @@ -426,24 +426,18 @@ static inline void tgen_arithi64(TCGContext *s, int c, int r0, int64_t val) } else if ((c == ARITH_ADD && val == -1) || (c == ARITH_SUB && val == 1)) { /* dec */ tcg_out_modrm(s, 0xff | P_REXW, 1, r0); - } else if (val == (int8_t)val) { - tcg_out_modrm(s, 0x83 | P_REXW, c, r0); - tcg_out8(s, val); - } else if (c == ARITH_AND && val == 0xffu) { - /* movzbl */ - tcg_out_modrm(s, 0xb6 | P_EXT | P_REXW, r0, r0); - } else if (c == ARITH_AND && val == 0xffffu) { - /* movzwl */ - tcg_out_modrm(s, 0xb7 | P_EXT | P_REXW, r0, r0); } else if (c == ARITH_AND && val == 0xffffffffu) { /* 32-bit mov zero extends */ tcg_out_modrm(s, 0x8b, r0, r0); + } else if (c == ARITH_AND && val == (uint32_t)val) { + /* AND with no high bits set can use a 32-bit operation. */ + tgen_arithi32(s, c, r0, (uint32_t)val); + } else if (val == (int8_t)val) { + tcg_out_modrm(s, 0x83 | P_REXW, c, r0); + tcg_out8(s, val); } else if (val == (int32_t)val) { tcg_out_modrm(s, 0x81 | P_REXW, c, r0); tcg_out32(s, val); - } else if (c == ARITH_AND && val == (uint32_t)val) { - tcg_out_modrm(s, 0x81, c, r0); - tcg_out32(s, val); } else { tcg_abort(); } @@ -1182,16 +1176,12 @@ static inline void tcg_out_op(TCGContext *s, int opc, const TCGArg *args, tcg_out_modrm(s, 0x63 | P_REXW, args[0], args[1]); break; case INDEX_op_ext8u_i32: + case INDEX_op_ext8u_i64: tcg_out_modrm(s, 0xb6 | P_EXT | P_REXB, args[0], args[1]); break; case INDEX_op_ext16u_i32: - tcg_out_modrm(s, 0xb7 | P_EXT, args[0], args[1]); - break; - case INDEX_op_ext8u_i64: - tcg_out_modrm(s, 0xb6 | P_EXT | P_REXW, args[0], args[1]); - break; case INDEX_op_ext16u_i64: - tcg_out_modrm(s, 0xb7 | P_EXT | P_REXW, args[0], args[1]); + tcg_out_modrm(s, 0xb7 | P_EXT, args[0], args[1]); break; case INDEX_op_ext32u_i64: tcg_out_modrm(s, 0x8b, args[0], args[1]); |