1/*
2 * RISC-V translation routines for the Zc[b,mp,mt] Standard Extensions.
3 *
4 * Copyright (c) 2021-2022 PLCT Lab
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2 or later, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program.  If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#define REQUIRE_ZCB(ctx) do {   \
20    if (!ctx->cfg_ptr->ext_zcb) \
21        return false;           \
22} while (0)
23
24#define REQUIRE_ZCMP(ctx) do {   \
25    if (!ctx->cfg_ptr->ext_zcmp) \
26        return false;            \
27} while (0)
28
29#define REQUIRE_ZCMT(ctx) do {   \
30    if (!ctx->cfg_ptr->ext_zcmt) \
31        return false;            \
32} while (0)
33
34static bool trans_c_zext_b(DisasContext *ctx, arg_c_zext_b *a)
35{
36    REQUIRE_ZCB(ctx);
37    return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext8u_tl);
38}
39
40static bool trans_c_zext_h(DisasContext *ctx, arg_c_zext_h *a)
41{
42    REQUIRE_ZCB(ctx);
43    REQUIRE_ZBB(ctx);
44    return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext16u_tl);
45}
46
47static bool trans_c_sext_b(DisasContext *ctx, arg_c_sext_b *a)
48{
49    REQUIRE_ZCB(ctx);
50    REQUIRE_ZBB(ctx);
51    return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext8s_tl);
52}
53
54static bool trans_c_sext_h(DisasContext *ctx, arg_c_sext_h *a)
55{
56    REQUIRE_ZCB(ctx);
57    REQUIRE_ZBB(ctx);
58    return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext16s_tl);
59}
60
61static bool trans_c_zext_w(DisasContext *ctx, arg_c_zext_w *a)
62{
63    REQUIRE_64BIT(ctx);
64    REQUIRE_ZCB(ctx);
65    REQUIRE_ZBA(ctx);
66    return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext32u_tl);
67}
68
69static bool trans_c_not(DisasContext *ctx, arg_c_not *a)
70{
71    REQUIRE_ZCB(ctx);
72    return gen_unary(ctx, a, EXT_NONE, tcg_gen_not_tl);
73}
74
75static bool trans_c_mul(DisasContext *ctx, arg_c_mul *a)
76{
77    REQUIRE_ZCB(ctx);
78    REQUIRE_M_OR_ZMMUL(ctx);
79    return gen_arith(ctx, a, EXT_NONE, tcg_gen_mul_tl, NULL);
80}
81
82static bool trans_c_lbu(DisasContext *ctx, arg_c_lbu *a)
83{
84    REQUIRE_ZCB(ctx);
85    return gen_load(ctx, a, MO_UB);
86}
87
88static bool trans_c_lhu(DisasContext *ctx, arg_c_lhu *a)
89{
90    REQUIRE_ZCB(ctx);
91    return gen_load(ctx, a, MO_UW);
92}
93
94static bool trans_c_lh(DisasContext *ctx, arg_c_lh *a)
95{
96    REQUIRE_ZCB(ctx);
97    return gen_load(ctx, a, MO_SW);
98}
99
100static bool trans_c_sb(DisasContext *ctx, arg_c_sb *a)
101{
102    REQUIRE_ZCB(ctx);
103    return gen_store(ctx, a, MO_UB);
104}
105
106static bool trans_c_sh(DisasContext *ctx, arg_c_sh *a)
107{
108    REQUIRE_ZCB(ctx);
109    return gen_store(ctx, a, MO_UW);
110}
111
112#define X_S0    8
113#define X_S1    9
114#define X_Sn    16
115
116static uint32_t decode_push_pop_list(DisasContext *ctx, target_ulong rlist)
117{
118    uint32_t reg_bitmap = 0;
119
120    if (has_ext(ctx, RVE) && rlist > 6) {
121        return 0;
122    }
123
124    switch (rlist) {
125    case 15:
126        reg_bitmap |=  1 << (X_Sn + 11) ;
127        reg_bitmap |=  1 << (X_Sn + 10) ;
128        /* FALL THROUGH */
129    case 14:
130        reg_bitmap |=  1 << (X_Sn + 9) ;
131        /* FALL THROUGH */
132    case 13:
133        reg_bitmap |=  1 << (X_Sn + 8) ;
134        /* FALL THROUGH */
135    case 12:
136        reg_bitmap |=  1 << (X_Sn + 7) ;
137        /* FALL THROUGH */
138    case 11:
139        reg_bitmap |=  1 << (X_Sn + 6) ;
140        /* FALL THROUGH */
141    case 10:
142        reg_bitmap |=  1 << (X_Sn + 5) ;
143        /* FALL THROUGH */
144    case 9:
145        reg_bitmap |=  1 << (X_Sn + 4) ;
146        /* FALL THROUGH */
147    case 8:
148        reg_bitmap |=  1 << (X_Sn + 3) ;
149        /* FALL THROUGH */
150    case 7:
151        reg_bitmap |=  1 << (X_Sn + 2) ;
152        /* FALL THROUGH */
153    case 6:
154        reg_bitmap |=  1 << X_S1 ;
155        /* FALL THROUGH */
156    case 5:
157        reg_bitmap |= 1 << X_S0;
158        /* FALL THROUGH */
159    case 4:
160        reg_bitmap |= 1 << xRA;
161        break;
162    default:
163        break;
164    }
165
166    return reg_bitmap;
167}
168
169static bool gen_pop(DisasContext *ctx, arg_cmpp *a, bool ret, bool ret_val)
170{
171    REQUIRE_ZCMP(ctx);
172
173    uint32_t reg_bitmap = decode_push_pop_list(ctx, a->urlist);
174    if (reg_bitmap == 0) {
175        return false;
176    }
177
178    MemOp memop = get_ol(ctx) == MXL_RV32 ? MO_TEUL : MO_TEUQ;
179    int reg_size = memop_size(memop);
180    target_ulong stack_adj = ROUND_UP(ctpop32(reg_bitmap) * reg_size, 16) +
181                             a->spimm;
182    TCGv sp = dest_gpr(ctx, xSP);
183    TCGv addr = tcg_temp_new();
184    int i;
185
186    tcg_gen_addi_tl(addr, sp, stack_adj - reg_size);
187
188    for (i = X_Sn + 11; i >= 0; i--) {
189        if (reg_bitmap & (1 << i)) {
190            TCGv dest = dest_gpr(ctx, i);
191            tcg_gen_qemu_ld_tl(dest, addr, ctx->mem_idx, memop);
192            gen_set_gpr(ctx, i, dest);
193            tcg_gen_subi_tl(addr, addr, reg_size);
194        }
195    }
196
197    tcg_gen_addi_tl(sp, sp, stack_adj);
198    gen_set_gpr(ctx, xSP, sp);
199
200    if (ret_val) {
201        gen_set_gpr(ctx, xA0, ctx->zero);
202    }
203
204    if (ret) {
205        TCGv ret_addr = get_gpr(ctx, xRA, EXT_SIGN);
206        tcg_gen_mov_tl(cpu_pc, ret_addr);
207        tcg_gen_lookup_and_goto_ptr();
208        ctx->base.is_jmp = DISAS_NORETURN;
209    }
210
211    return true;
212}
213
214static bool trans_cm_push(DisasContext *ctx, arg_cm_push *a)
215{
216    REQUIRE_ZCMP(ctx);
217
218    uint32_t reg_bitmap = decode_push_pop_list(ctx, a->urlist);
219    if (reg_bitmap == 0) {
220        return false;
221    }
222
223    MemOp memop = get_ol(ctx) == MXL_RV32 ? MO_TEUL : MO_TEUQ;
224    int reg_size = memop_size(memop);
225    target_ulong stack_adj = ROUND_UP(ctpop32(reg_bitmap) * reg_size, 16) +
226                             a->spimm;
227    TCGv sp = dest_gpr(ctx, xSP);
228    TCGv addr = tcg_temp_new();
229    int i;
230
231    tcg_gen_subi_tl(addr, sp, reg_size);
232
233    for (i = X_Sn + 11; i >= 0; i--) {
234        if (reg_bitmap & (1 << i)) {
235            TCGv val = get_gpr(ctx, i, EXT_NONE);
236            tcg_gen_qemu_st_tl(val, addr, ctx->mem_idx, memop);
237            tcg_gen_subi_tl(addr, addr, reg_size);
238        }
239    }
240
241    tcg_gen_subi_tl(sp, sp, stack_adj);
242    gen_set_gpr(ctx, xSP, sp);
243
244    return true;
245}
246
247static bool trans_cm_pop(DisasContext *ctx, arg_cm_pop *a)
248{
249    return gen_pop(ctx, a, false, false);
250}
251
252static bool trans_cm_popret(DisasContext *ctx, arg_cm_popret *a)
253{
254    return gen_pop(ctx, a, true, false);
255}
256
257static bool trans_cm_popretz(DisasContext *ctx, arg_cm_popret *a)
258{
259    return gen_pop(ctx, a, true, true);
260}
261
262static bool trans_cm_mva01s(DisasContext *ctx, arg_cm_mva01s *a)
263{
264    REQUIRE_ZCMP(ctx);
265
266    TCGv src1 = get_gpr(ctx, a->rs1, EXT_NONE);
267    TCGv src2 = get_gpr(ctx, a->rs2, EXT_NONE);
268
269    gen_set_gpr(ctx, xA0, src1);
270    gen_set_gpr(ctx, xA1, src2);
271
272    return true;
273}
274
275static bool trans_cm_mvsa01(DisasContext *ctx, arg_cm_mvsa01 *a)
276{
277    REQUIRE_ZCMP(ctx);
278
279    if (a->rs1 == a->rs2) {
280        return false;
281    }
282
283    TCGv a0 = get_gpr(ctx, xA0, EXT_NONE);
284    TCGv a1 = get_gpr(ctx, xA1, EXT_NONE);
285
286    gen_set_gpr(ctx, a->rs1, a0);
287    gen_set_gpr(ctx, a->rs2, a1);
288
289    return true;
290}
291
292static bool trans_cm_jalt(DisasContext *ctx, arg_cm_jalt *a)
293{
294    REQUIRE_ZCMT(ctx);
295
296    /*
297     * Update pc to current for the non-unwinding exception
298     * that might come from cpu_ld*_code() in the helper.
299     */
300    tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next);
301    gen_helper_cm_jalt(cpu_pc, cpu_env, tcg_constant_i32(a->index));
302
303    /* c.jt vs c.jalt depends on the index. */
304    if (a->index >= 32) {
305        gen_set_gpri(ctx, xRA, ctx->pc_succ_insn);
306    }
307
308    tcg_gen_lookup_and_goto_ptr();
309    ctx->base.is_jmp = DISAS_NORETURN;
310    return true;
311}
312