From: Alex Bennée <alex.ben...@linaro.org>
Implement the non-carry forms of addition and subtraction
(immediate, extended register and shifted register).
This includes the code to calculate NZCV if the instruction
calls for setting the flags.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
Reviewed-by: Richard Henderson <r...@twiddle.net>
---
target-arm/translate-a64.c | 292 ++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 286 insertions(+), 6 deletions(-)
diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c
index 1b34a98..7227bb0 100644
--- a/target-arm/translate-a64.c
+++ b/target-arm/translate-a64.c
@@ -297,6 +297,102 @@ static inline void gen_logic_CC(int sf, TCGv_i64 result)
tcg_gen_movi_i32(cpu_VF, 0);
}
+/* dest = T0 + T1; compute C, N, V and Z flags */
+static void gen_add_CC(int sf, TCGv_i64 dest, TCGv_i64 t0, TCGv_i64 t1)
+{
+ if (sf) {
+ TCGv_i64 result, flag, tmp;
+ result = tcg_temp_new_i64();
+ flag = tcg_temp_new_i64();
+ tmp = tcg_temp_new_i64();
+
+ tcg_gen_movi_i64(tmp, 0);
+ tcg_gen_add2_i64(result, flag, t0, tmp, t1, tmp);
+
+ tcg_gen_trunc_i64_i32(cpu_CF, flag);
+
+ gen_set_NZ64(result);
+
+ tcg_gen_xor_i64(flag, result, t0);
+ tcg_gen_xor_i64(tmp, t0, t1);
+ tcg_gen_andc_i64(flag, flag, tmp);
+ tcg_temp_free_i64(tmp);
+ tcg_gen_shri_i64(flag, flag, 32);
+ tcg_gen_trunc_i64_i32(cpu_VF, flag);
+
+ tcg_gen_mov_i64(dest, result);
+ tcg_temp_free_i64(result);
+ tcg_temp_free_i64(flag);
+ } else {
+ /* 32 bit arithmetic */
+ TCGv_i32 t0_32 = tcg_temp_new_i32();
+ TCGv_i32 t1_32 = tcg_temp_new_i32();
+ TCGv_i32 tmp = tcg_temp_new_i32();
+
+ tcg_gen_movi_i32(tmp, 0);
+ tcg_gen_trunc_i64_i32(t0_32, t0);
+ tcg_gen_trunc_i64_i32(t1_32, t1);
+ tcg_gen_add2_i32(cpu_NF, cpu_CF, t0_32, tmp, t1_32, tmp);
+ tcg_gen_mov_i32(cpu_ZF, cpu_NF);
+ tcg_gen_xor_i32(cpu_VF, cpu_NF, t0_32);
+ tcg_gen_xor_i32(tmp, t0_32, t1_32);
+ tcg_gen_andc_i32(cpu_VF, cpu_VF, tmp);
+ tcg_gen_extu_i32_i64(dest, cpu_NF);
+
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(t0_32);
+ tcg_temp_free_i32(t1_32);
+ }
+}
+
+/* dest = T0 - T1; compute C, N, V and Z flags */
+static void gen_sub_CC(int sf, TCGv_i64 dest, TCGv_i64 t0, TCGv_i64 t1)
+{
+ if (sf) {
+ /* 64 bit arithmetic */
+ TCGv_i64 result, flag, tmp;
+
+ result = tcg_temp_new_i64();
+ flag = tcg_temp_new_i64();
+ tcg_gen_sub_i64(result, t0, t1);
+
+ gen_set_NZ64(result);
+
+ tcg_gen_setcond_i64(TCG_COND_GEU, flag, t0, t1);
+ tcg_gen_trunc_i64_i32(cpu_CF, flag);
+
+ tcg_gen_xor_i64(flag, result, t0);
+ tmp = tcg_temp_new_i64();
+ tcg_gen_xor_i64(tmp, t0, t1);
+ tcg_gen_and_i64(flag, flag, tmp);
+ tcg_temp_free_i64(tmp);
+ tcg_gen_shri_i64(flag, flag, 32);
+ tcg_gen_trunc_i64_i32(cpu_VF, flag);
+ tcg_gen_mov_i64(dest, result);
+ tcg_temp_free_i64(flag);
+ tcg_temp_free_i64(result);
+ } else {
+ /* 32 bit arithmetic */
+ TCGv_i32 t0_32 = tcg_temp_new_i32();
+ TCGv_i32 t1_32 = tcg_temp_new_i32();
+ TCGv_i32 tmp;
+
+ tcg_gen_trunc_i64_i32(t0_32, t0);
+ tcg_gen_trunc_i64_i32(t1_32, t1);
+ tcg_gen_sub_i32(cpu_NF, t0_32, t1_32);
+ tcg_gen_mov_i32(cpu_ZF, cpu_NF);
+ tcg_gen_setcond_i32(TCG_COND_GEU, cpu_CF, t0_32, t1_32);
+ tcg_gen_xor_i32(cpu_VF, cpu_NF, t0_32);
+ tmp = tcg_temp_new_i32();
+ tcg_gen_xor_i32(tmp, t0_32, t1_32);
+ tcg_temp_free_i32(t0_32);
+ tcg_temp_free_i32(t1_32);
+ tcg_gen_and_i32(cpu_VF, cpu_VF, tmp);
+ tcg_temp_free_i32(tmp);
+ tcg_gen_extu_i32_i64(dest, cpu_NF);
+ }
+}
+
/*
* Load/Store generators
*/
@@ -1326,10 +1422,68 @@ static void disas_pc_rel_adr(DisasContext *s, uint32_t
insn)
tcg_gen_movi_i64(cpu_reg(s, rd), base + offset);
}
-/* Add/subtract (immediate) */
+/*
+ * C3.4.1 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 |
+ * +--+--+--+-----------+-----+-------------+-----+-----+
+ *
+ * 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
+ */
static void disas_add_sub_imm(DisasContext *s, uint32_t insn)
{
- unsupported_encoding(s, 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 setflags = extract32(insn, 29, 1);
+ bool sub_op = extract32(insn, 30, 1);
+ bool is_64bit = extract32(insn, 31, 1);
+
+ TCGv_i64 tcg_rn = cpu_reg_sp(s, rn);
+ 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:
+ imm <<= 12;
+ break;
+ default:
+ unallocated_encoding(s);
+ return;
+ }
+
+ tcg_result = tcg_temp_new_i64();
+ if (!setflags) {
+ if (sub_op) {
+ tcg_gen_subi_i64(tcg_result, tcg_rn, imm);
+ } else {
+ tcg_gen_addi_i64(tcg_result, tcg_rn, imm);
+ }
+ } else {
+ TCGv_i64 tcg_imm = tcg_const_i64(imm);
+ if (sub_op) {
+ gen_sub_CC(is_64bit, tcg_result, tcg_rn, tcg_imm);
+ } else {
+ gen_add_CC(is_64bit, tcg_result, tcg_rn, tcg_imm);
+ }
+ tcg_temp_free_i64(tcg_imm);
+ }
+
+ if (is_64bit) {
+ tcg_gen_mov_i64(tcg_rd, tcg_result);
+ } else {
+ tcg_gen_ext32u_i64(tcg_rd, tcg_result);
+ }
+
+ tcg_temp_free_i64(tcg_result);
}
/* The input should be a value in the bottom e bits (with higher
@@ -1787,16 +1941,142 @@ static void disas_logic_reg(DisasContext *s, uint32_t
insn)
}
}
-/* Add/subtract (extended register) */
+/*
+ * C3.5.1 Add/subtract (extended register)
+ *
+ * 31|30|29|28 24|23 22|21|20 16|15 13|12 10|9 5|4 0|
+ * +--+--+--+-----------+-----+--+-------+------+------+----+----+
+ * |sf|op| S| 0 1 0 1 1 | opt | 1| Rm |option| imm3 | Rn | Rd |
+ * +--+--+--+-----------+-----+--+-------+------+------+----+----+
+ *
+ * sf: 0 -> 32bit, 1 -> 64bit
+ * op: 0 -> add , 1 -> sub
+ * S: 1 -> set flags
+ * opt: 00
+ * option: extension type (see DecodeRegExtend)
+ * imm3: optional shift to Rm
+ *
+ * Rd = Rn + LSL(extend(Rm), amount)
+ */
static void disas_add_sub_ext_reg(DisasContext *s, uint32_t insn)
{
- unsupported_encoding(s, insn);
+ int rd = extract32(insn, 0, 5);
+ int rn = extract32(insn, 5, 5);
+ int imm3 = extract32(insn, 10, 3);
+ int option = extract32(insn, 13, 3);
+ int rm = extract32(insn, 16, 5);
+ bool setflags = extract32(insn, 29, 1);
+ bool sub_op = extract32(insn, 30, 1);
+ bool sf = extract32(insn, 31, 1);
+
+ TCGv_i64 tcg_rm, tcg_rn; /* temps */
+ TCGv_i64 tcg_rd;
+ TCGv_i64 tcg_result;
+
+ if (imm3 > 4) {
+ unallocated_encoding(s);
+ return;
+ }
+
+ /* non-flag setting ops may use SP */
+ if (!setflags) {
+ tcg_rn = read_cpu_reg_sp(s, rn, sf);
+ tcg_rd = cpu_reg_sp(s, rd);
+ } else {
+ tcg_rn = read_cpu_reg(s, rn, sf);
+ tcg_rd = cpu_reg(s, rd);
+ }
+
+ tcg_rm = read_cpu_reg(s, rm, sf);
+ ext_and_shift_reg(tcg_rm, tcg_rm, option, imm3);
+
+ tcg_result = tcg_temp_new_i64();
+
+ if (!setflags) {
+ if (sub_op) {
+ tcg_gen_sub_i64(tcg_result, tcg_rn, tcg_rm);
+ } else {
+ tcg_gen_add_i64(tcg_result, tcg_rn, tcg_rm);
+ }
+ } else {
+ if (sub_op) {
+ gen_sub_CC(sf, tcg_result, tcg_rn, tcg_rm);
+ } else {
+ gen_add_CC(sf, tcg_result, tcg_rn, tcg_rm);
+ }
+ }
+
+ if (sf) {
+ tcg_gen_mov_i64(tcg_rd, tcg_result);
+ } else {
+ tcg_gen_ext32u_i64(tcg_rd, tcg_result);
+ }
+
+ tcg_temp_free_i64(tcg_result);
}
-/* Add/subtract (shifted register) */
+/*
+ * C3.5.2 Add/subtract (shifted register)
+ *
+ * 31 30 29 28 24 23 22 21 20 16 15 10 9 5 4 0
+ * +--+--+--+-----------+-----+--+-------+---------+------+------+
+ * |sf|op| S| 0 1 0 1 1 |shift| 0| Rm | imm6 | Rn | Rd |
+ * +--+--+--+-----------+-----+--+-------+---------+------+------+
+ *
+ * sf: 0 -> 32bit, 1 -> 64bit
+ * op: 0 -> add , 1 -> sub
+ * S: 1 -> set flags
+ * shift: 00 -> LSL, 01 -> LSR, 10 -> ASR, 11 -> RESERVED
+ * imm6: Shift amount to apply to Rm before the add/sub
+ */
static void disas_add_sub_reg(DisasContext *s, uint32_t insn)
{
- unsupported_encoding(s, insn);
+ int rd = extract32(insn, 0, 5);
+ int rn = extract32(insn, 5, 5);
+ int imm6 = extract32(insn, 10, 6);
+ int rm = extract32(insn, 16, 5);
+ int shift_type = extract32(insn, 22, 2);
+ bool setflags = extract32(insn, 29, 1);
+ bool sub_op = extract32(insn, 30, 1);
+ bool sf = extract32(insn, 31, 1);
+
+ TCGv_i64 tcg_rd = cpu_reg(s, rd);
+ TCGv_i64 tcg_rn, tcg_rm;
+ TCGv_i64 tcg_result;
+
+ if ((shift_type == 3) || (!sf && (imm6 > 31))) {
+ unallocated_encoding(s);
+ return;
+ }
+
+ tcg_rn = read_cpu_reg(s, rn, sf);
+ tcg_rm = read_cpu_reg(s, rm, sf);
+
+ shift_reg_imm(tcg_rm, tcg_rm, sf, shift_type, imm6);
+
+ tcg_result = tcg_temp_new_i64();
+
+ if (!setflags) {
+ if (sub_op) {
+ tcg_gen_sub_i64(tcg_result, tcg_rn, tcg_rm);
+ } else {
+ tcg_gen_add_i64(tcg_result, tcg_rn, tcg_rm);
+ }
+ } else {
+ if (sub_op) {
+ gen_sub_CC(sf, tcg_result, tcg_rn, tcg_rm);
+ } else {
+ gen_add_CC(sf, tcg_result, tcg_rn, tcg_rm);
+ }
+ }
+
+ if (sf) {
+ tcg_gen_mov_i64(tcg_rd, tcg_result);
+ } else {
+ tcg_gen_ext32u_i64(tcg_rd, tcg_result);
+ }
+
+ tcg_temp_free_i64(tcg_result);
}
/* Data-processing (3 source) */
--
1.8.5
