diff options
| author | Richard Henderson <rth@twiddle.net> | 2015-09-14 14:39:48 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2015-09-14 14:39:48 +0100 |
| commit | ef60151bee9a95e3a5cc98b345a19ed7eb435ddb (patch) | |
| tree | 4160c0f7bab24b6319c7e123aaeb900099714fa6 /target-arm | |
| parent | 6e061029d74455d83f6fa070ac33de7a356cf60d (diff) | |
target-arm: Recognize SXTB, SXTH, SXTW, ASR
These are all special case aliases of SBFM.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1441909103-24666-8-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'target-arm')
| -rw-r--r-- | target-arm/translate-a64.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c index d17ca19f03..8ae68148ef 100644 --- a/target-arm/translate-a64.c +++ b/target-arm/translate-a64.c @@ -3017,7 +3017,28 @@ static void disas_bitfield(DisasContext *s, uint32_t insn) tcg_rd = cpu_reg(s, rd); tcg_tmp = read_cpu_reg(s, rn, sf); - /* OPTME: probably worth recognizing common cases of ext{8,16,32}{u,s} */ + /* Recognize the common aliases. */ + if (opc == 0) { /* SBFM */ + if (ri == 0) { + if (si == 7) { /* SXTB */ + tcg_gen_ext8s_i64(tcg_rd, tcg_tmp); + goto done; + } else if (si == 15) { /* SXTH */ + tcg_gen_ext16s_i64(tcg_rd, tcg_tmp); + goto done; + } else if (si == 31) { /* SXTW */ + tcg_gen_ext32s_i64(tcg_rd, tcg_tmp); + goto done; + } + } + if (si == 63 || (si == 31 && ri <= si)) { /* ASR */ + if (si == 31) { + tcg_gen_ext32s_i64(tcg_tmp, tcg_tmp); + } + tcg_gen_sari_i64(tcg_rd, tcg_tmp, ri); + goto done; + } + } if (opc != 1) { /* SBFM or UBFM */ tcg_gen_movi_i64(tcg_rd, 0); @@ -3042,6 +3063,7 @@ static void disas_bitfield(DisasContext *s, uint32_t insn) tcg_gen_sari_i64(tcg_rd, tcg_rd, 64 - (pos + len)); } + done: if (!sf) { /* zero extend final result */ tcg_gen_ext32u_i64(tcg_rd, tcg_rd); } |