diff options
| -rw-r--r-- | target/arm/t32.decode | 8 | ||||
| -rw-r--r-- | target/arm/translate.c | 93 |
2 files changed, 99 insertions, 2 deletions
diff --git a/target/arm/t32.decode b/target/arm/t32.decode index 3015731a8d..8152739b52 100644 --- a/target/arm/t32.decode +++ b/target/arm/t32.decode @@ -659,4 +659,12 @@ BL 1111 0. .......... 11.1 ............ @branch24 BF 1111 0 boff:4 10 ----- 1110 - ---------- 1 # BF BF 1111 0 boff:4 11 ----- 1110 0 0000000000 1 # BFX, BFLX ] + [ + # LE and WLS immediate + %lob_imm 1:10 11:1 !function=times_2 + + DLS 1111 0 0000 100 rn:4 1110 0000 0000 0001 + WLS 1111 0 0000 100 rn:4 1100 . .......... 1 imm=%lob_imm + LE 1111 0 0000 0 f:1 0 1111 1100 . .......... 1 imm=%lob_imm + ] } diff --git a/target/arm/translate.c b/target/arm/translate.c index a5ebe56880..38371db540 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -2490,17 +2490,23 @@ static void gen_goto_tb(DisasContext *s, int n, target_ulong dest) s->base.is_jmp = DISAS_NORETURN; } -static inline void gen_jmp (DisasContext *s, uint32_t dest) +/* Jump, specifying which TB number to use if we gen_goto_tb() */ +static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno) { if (unlikely(is_singlestepping(s))) { /* An indirect jump so that we still trigger the debug exception. */ gen_set_pc_im(s, dest); s->base.is_jmp = DISAS_JUMP; } else { - gen_goto_tb(s, 0, dest); + gen_goto_tb(s, tbno, dest); } } +static inline void gen_jmp(DisasContext *s, uint32_t dest) +{ + gen_jmp_tb(s, dest, 0); +} + static inline void gen_mulxy(TCGv_i32 t0, TCGv_i32 t1, int x, int y) { if (x) @@ -7991,6 +7997,89 @@ static bool trans_BF(DisasContext *s, arg_BF *a) return true; } +static bool trans_DLS(DisasContext *s, arg_DLS *a) +{ + /* M-profile low-overhead loop start */ + TCGv_i32 tmp; + + if (!dc_isar_feature(aa32_lob, s)) { + return false; + } + if (a->rn == 13 || a->rn == 15) { + /* CONSTRAINED UNPREDICTABLE: we choose to UNDEF */ + return false; + } + + /* Not a while loop, no tail predication: just set LR to the count */ + tmp = load_reg(s, a->rn); + store_reg(s, 14, tmp); + return true; +} + +static bool trans_WLS(DisasContext *s, arg_WLS *a) +{ + /* M-profile low-overhead while-loop start */ + TCGv_i32 tmp; + TCGLabel *nextlabel; + + if (!dc_isar_feature(aa32_lob, s)) { + return false; + } + if (a->rn == 13 || a->rn == 15) { + /* CONSTRAINED UNPREDICTABLE: we choose to UNDEF */ + return false; + } + if (s->condexec_mask) { + /* + * WLS in an IT block is CONSTRAINED UNPREDICTABLE; + * we choose to UNDEF, because otherwise our use of + * gen_goto_tb(1) would clash with the use of TB exit 1 + * in the dc->condjmp condition-failed codepath in + * arm_tr_tb_stop() and we'd get an assertion. + */ + return false; + } + nextlabel = gen_new_label(); + tcg_gen_brcondi_i32(TCG_COND_EQ, cpu_R[a->rn], 0, nextlabel); + tmp = load_reg(s, a->rn); + store_reg(s, 14, tmp); + gen_jmp_tb(s, s->base.pc_next, 1); + + gen_set_label(nextlabel); + gen_jmp(s, read_pc(s) + a->imm); + return true; +} + +static bool trans_LE(DisasContext *s, arg_LE *a) +{ + /* + * M-profile low-overhead loop end. The architecture permits an + * implementation to discard the LO_BRANCH_INFO cache at any time, + * and we take the IMPDEF option to never set it in the first place + * (equivalent to always discarding it immediately), because for QEMU + * a "real" implementation would be complicated and wouldn't execute + * any faster. + */ + TCGv_i32 tmp; + + if (!dc_isar_feature(aa32_lob, s)) { + return false; + } + + if (!a->f) { + /* Not loop-forever. If LR <= 1 this is the last loop: do nothing. */ + arm_gen_condlabel(s); + tcg_gen_brcondi_i32(TCG_COND_LEU, cpu_R[14], 1, s->condlabel); + /* Decrement LR */ + tmp = load_reg(s, 14); + tcg_gen_addi_i32(tmp, tmp, -1); + store_reg(s, 14, tmp); + } + /* Jump back to the loop start */ + gen_jmp(s, read_pc(s) - a->imm); + return true; +} + static bool op_tbranch(DisasContext *s, arg_tbranch *a, bool half) { TCGv_i32 addr, tmp; |