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| author | Richard Henderson <rth@twiddle.net> | 2012-09-19 13:50:07 -0700 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2013-01-05 12:18:45 -0800 |
| commit | f24c49c24a4979fe50eff7afe18f371f5809177d (patch) | |
| tree | b2b5e77d879cdc2cead9422ec2ab5559b7f85097 /target-s390x | |
| parent | d074ac6d266129f8f4e2aac5b0e6c39c22964d9a (diff) | |
| download | qemu-f24c49c24a4979fe50eff7afe18f371f5809177d.zip qemu-f24c49c24a4979fe50eff7afe18f371f5809177d.tar.gz qemu-f24c49c24a4979fe50eff7afe18f371f5809177d.tar.bz2 | |
target-s390: Optmize emitting discards
While they aren't expensive, they aren't free to process. When we
know that the three cc helper variables are dead, don't kill them.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'target-s390x')
| -rw-r--r-- | target-s390x/translate.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/target-s390x/translate.c b/target-s390x/translate.c index 7f8a550..cfe3766 100644 --- a/target-s390x/translate.c +++ b/target-s390x/translate.c @@ -367,25 +367,41 @@ static TCGv_i64 get_address(DisasContext *s, int x2, int b2, int d2) return tmp; } +static inline bool live_cc_data(DisasContext *s) +{ + return (s->cc_op != CC_OP_DYNAMIC + && s->cc_op != CC_OP_STATIC + && s->cc_op > 3); +} + static inline void gen_op_movi_cc(DisasContext *s, uint32_t val) { + if (live_cc_data(s)) { + tcg_gen_discard_i64(cc_src); + tcg_gen_discard_i64(cc_dst); + tcg_gen_discard_i64(cc_vr); + } s->cc_op = CC_OP_CONST0 + val; } static void gen_op_update1_cc_i64(DisasContext *s, enum cc_op op, TCGv_i64 dst) { - tcg_gen_discard_i64(cc_src); + if (live_cc_data(s)) { + tcg_gen_discard_i64(cc_src); + tcg_gen_discard_i64(cc_vr); + } tcg_gen_mov_i64(cc_dst, dst); - tcg_gen_discard_i64(cc_vr); s->cc_op = op; } static void gen_op_update2_cc_i64(DisasContext *s, enum cc_op op, TCGv_i64 src, TCGv_i64 dst) { + if (live_cc_data(s)) { + tcg_gen_discard_i64(cc_vr); + } tcg_gen_mov_i64(cc_src, src); tcg_gen_mov_i64(cc_dst, dst); - tcg_gen_discard_i64(cc_vr); s->cc_op = op; } @@ -421,9 +437,11 @@ static void gen_set_cc_nz_f128(DisasContext *s, TCGv_i64 vh, TCGv_i64 vl) /* CC value is in env->cc_op */ static void set_cc_static(DisasContext *s) { - tcg_gen_discard_i64(cc_src); - tcg_gen_discard_i64(cc_dst); - tcg_gen_discard_i64(cc_vr); + if (live_cc_data(s)) { + tcg_gen_discard_i64(cc_src); + tcg_gen_discard_i64(cc_dst); + tcg_gen_discard_i64(cc_vr); + } s->cc_op = CC_OP_STATIC; } |