diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2020-06-25 20:31:08 -0700 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2020-06-26 14:31:12 +0100 |
| commit | 21a8b343eaae63f6984f9a200092b0ea167647f1 (patch) | |
| tree | 22aa7f8b971043464a7f04952b93563866bdef55 /target/arm | |
| parent | da54941f45b820cbaca72aa6efd5669b3dc86e2f (diff) | |
target/arm: Revise decoding for disas_add_sub_imm
The current Arm ARM has adjusted the official decode of
"Add/subtract (immediate)" so that the shift field is only bit 22,
and bit 23 is part of the op1 field of the parent category
"Data processing - immediate".
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200626033144.790098-11-richard.henderson@linaro.org
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'target/arm')
| -rw-r--r-- | target/arm/translate-a64.c | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 30683061f9..03aa092598 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -3754,22 +3754,22 @@ static void disas_pc_rel_adr(DisasContext *s, uint32_t insn) /* * Add/subtract (immediate) * - * 31 30 29 28 24 23 22 21 10 9 5 4 0 - * +--+--+--+-----------+-----+-------------+-----+-----+ - * |sf|op| S| 1 0 0 0 1 |shift| imm12 | Rn | Rd | - * +--+--+--+-----------+-----+-------------+-----+-----+ + * 31 30 29 28 23 22 21 10 9 5 4 0 + * +--+--+--+-------------+--+-------------+-----+-----+ + * |sf|op| S| 1 0 0 0 1 0 |sh| imm12 | Rn | Rd | + * +--+--+--+-------------+--+-------------+-----+-----+ * * sf: 0 -> 32bit, 1 -> 64bit * op: 0 -> add , 1 -> sub * S: 1 -> set flags - * shift: 00 -> LSL imm by 0, 01 -> LSL imm by 12 + * sh: 1 -> LSL imm by 12 */ static void disas_add_sub_imm(DisasContext *s, uint32_t insn) { int rd = extract32(insn, 0, 5); int rn = extract32(insn, 5, 5); uint64_t imm = extract32(insn, 10, 12); - int shift = extract32(insn, 22, 2); + bool shift = extract32(insn, 22, 1); bool setflags = extract32(insn, 29, 1); bool sub_op = extract32(insn, 30, 1); bool is_64bit = extract32(insn, 31, 1); @@ -3778,15 +3778,8 @@ static void disas_add_sub_imm(DisasContext *s, uint32_t insn) TCGv_i64 tcg_rd = setflags ? cpu_reg(s, rd) : cpu_reg_sp(s, rd); TCGv_i64 tcg_result; - switch (shift) { - case 0x0: - break; - case 0x1: + if (shift) { imm <<= 12; - break; - default: - unallocated_encoding(s); - return; } tcg_result = tcg_temp_new_i64(); @@ -4174,7 +4167,7 @@ static void disas_data_proc_imm(DisasContext *s, uint32_t insn) case 0x20: case 0x21: /* PC-rel. addressing */ disas_pc_rel_adr(s, insn); break; - case 0x22: case 0x23: /* Add/subtract (immediate) */ + case 0x22: /* Add/subtract (immediate) */ disas_add_sub_imm(s, insn); break; case 0x24: /* Logical (immediate) */ |