1/*
2 * RISC-V translation routines for the RVXI Base Integer Instruction Set.
3 *
4 * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
5 * Copyright (c) 2018 Peer Adelt, peer.adelt@hni.uni-paderborn.de
6 *                    Bastian Koppelmann, kbastian@mail.uni-paderborn.de
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2 or later, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21static bool trans_illegal(DisasContext *ctx, arg_empty *a)
22{
23    gen_exception_illegal(ctx);
24    return true;
25}
26
27static bool trans_c64_illegal(DisasContext *ctx, arg_empty *a)
28{
29     REQUIRE_64BIT(ctx);
30     return trans_illegal(ctx, a);
31}
32
33static bool trans_lui(DisasContext *ctx, arg_lui *a)
34{
35    if (a->rd != 0) {
36        tcg_gen_movi_tl(cpu_gpr[a->rd], a->imm);
37    }
38    return true;
39}
40
41static bool trans_auipc(DisasContext *ctx, arg_auipc *a)
42{
43    if (a->rd != 0) {
44        tcg_gen_movi_tl(cpu_gpr[a->rd], a->imm + ctx->base.pc_next);
45    }
46    return true;
47}
48
49static bool trans_jal(DisasContext *ctx, arg_jal *a)
50{
51    gen_jal(ctx, a->rd, a->imm);
52    return true;
53}
54
55static bool trans_jalr(DisasContext *ctx, arg_jalr *a)
56{
57    TCGLabel *misaligned = NULL;
58
59    tcg_gen_addi_tl(cpu_pc, get_gpr(ctx, a->rs1, EXT_NONE), a->imm);
60    tcg_gen_andi_tl(cpu_pc, cpu_pc, (target_ulong)-2);
61
62    if (!has_ext(ctx, RVC)) {
63        TCGv t0 = tcg_temp_new();
64
65        misaligned = gen_new_label();
66        tcg_gen_andi_tl(t0, cpu_pc, 0x2);
67        tcg_gen_brcondi_tl(TCG_COND_NE, t0, 0x0, misaligned);
68        tcg_temp_free(t0);
69    }
70
71    if (a->rd != 0) {
72        tcg_gen_movi_tl(cpu_gpr[a->rd], ctx->pc_succ_insn);
73    }
74    tcg_gen_lookup_and_goto_ptr();
75
76    if (misaligned) {
77        gen_set_label(misaligned);
78        gen_exception_inst_addr_mis(ctx);
79    }
80    ctx->base.is_jmp = DISAS_NORETURN;
81
82    return true;
83}
84
85static bool gen_branch(DisasContext *ctx, arg_b *a, TCGCond cond)
86{
87    TCGLabel *l = gen_new_label();
88    TCGv src1 = get_gpr(ctx, a->rs1, EXT_SIGN);
89    TCGv src2 = get_gpr(ctx, a->rs2, EXT_SIGN);
90
91    tcg_gen_brcond_tl(cond, src1, src2, l);
92    gen_goto_tb(ctx, 1, ctx->pc_succ_insn);
93
94    gen_set_label(l); /* branch taken */
95
96    if (!has_ext(ctx, RVC) && ((ctx->base.pc_next + a->imm) & 0x3)) {
97        /* misaligned */
98        gen_exception_inst_addr_mis(ctx);
99    } else {
100        gen_goto_tb(ctx, 0, ctx->base.pc_next + a->imm);
101    }
102    ctx->base.is_jmp = DISAS_NORETURN;
103
104    return true;
105}
106
107static bool trans_beq(DisasContext *ctx, arg_beq *a)
108{
109    return gen_branch(ctx, a, TCG_COND_EQ);
110}
111
112static bool trans_bne(DisasContext *ctx, arg_bne *a)
113{
114    return gen_branch(ctx, a, TCG_COND_NE);
115}
116
117static bool trans_blt(DisasContext *ctx, arg_blt *a)
118{
119    return gen_branch(ctx, a, TCG_COND_LT);
120}
121
122static bool trans_bge(DisasContext *ctx, arg_bge *a)
123{
124    return gen_branch(ctx, a, TCG_COND_GE);
125}
126
127static bool trans_bltu(DisasContext *ctx, arg_bltu *a)
128{
129    return gen_branch(ctx, a, TCG_COND_LTU);
130}
131
132static bool trans_bgeu(DisasContext *ctx, arg_bgeu *a)
133{
134    return gen_branch(ctx, a, TCG_COND_GEU);
135}
136
137static bool gen_load(DisasContext *ctx, arg_lb *a, MemOp memop)
138{
139    TCGv dest = dest_gpr(ctx, a->rd);
140    TCGv addr = get_gpr(ctx, a->rs1, EXT_NONE);
141
142    if (a->imm) {
143        TCGv temp = temp_new(ctx);
144        tcg_gen_addi_tl(temp, addr, a->imm);
145        addr = temp;
146    }
147    addr = gen_pm_adjust_address(ctx, addr);
148
149    tcg_gen_qemu_ld_tl(dest, addr, ctx->mem_idx, memop);
150    gen_set_gpr(ctx, a->rd, dest);
151    return true;
152}
153
154static bool trans_lb(DisasContext *ctx, arg_lb *a)
155{
156    return gen_load(ctx, a, MO_SB);
157}
158
159static bool trans_lh(DisasContext *ctx, arg_lh *a)
160{
161    return gen_load(ctx, a, MO_TESW);
162}
163
164static bool trans_lw(DisasContext *ctx, arg_lw *a)
165{
166    return gen_load(ctx, a, MO_TESL);
167}
168
169static bool trans_lbu(DisasContext *ctx, arg_lbu *a)
170{
171    return gen_load(ctx, a, MO_UB);
172}
173
174static bool trans_lhu(DisasContext *ctx, arg_lhu *a)
175{
176    return gen_load(ctx, a, MO_TEUW);
177}
178
179static bool gen_store(DisasContext *ctx, arg_sb *a, MemOp memop)
180{
181    TCGv addr = get_gpr(ctx, a->rs1, EXT_NONE);
182    TCGv data = get_gpr(ctx, a->rs2, EXT_NONE);
183
184    if (a->imm) {
185        TCGv temp = temp_new(ctx);
186        tcg_gen_addi_tl(temp, addr, a->imm);
187        addr = temp;
188    }
189    addr = gen_pm_adjust_address(ctx, addr);
190
191    tcg_gen_qemu_st_tl(data, addr, ctx->mem_idx, memop);
192    return true;
193}
194
195static bool trans_sb(DisasContext *ctx, arg_sb *a)
196{
197    return gen_store(ctx, a, MO_SB);
198}
199
200static bool trans_sh(DisasContext *ctx, arg_sh *a)
201{
202    return gen_store(ctx, a, MO_TESW);
203}
204
205static bool trans_sw(DisasContext *ctx, arg_sw *a)
206{
207    return gen_store(ctx, a, MO_TESL);
208}
209
210static bool trans_lwu(DisasContext *ctx, arg_lwu *a)
211{
212    REQUIRE_64BIT(ctx);
213    return gen_load(ctx, a, MO_TEUL);
214}
215
216static bool trans_ld(DisasContext *ctx, arg_ld *a)
217{
218    REQUIRE_64BIT(ctx);
219    return gen_load(ctx, a, MO_TEQ);
220}
221
222static bool trans_sd(DisasContext *ctx, arg_sd *a)
223{
224    REQUIRE_64BIT(ctx);
225    return gen_store(ctx, a, MO_TEQ);
226}
227
228static bool trans_addi(DisasContext *ctx, arg_addi *a)
229{
230    return gen_arith_imm_fn(ctx, a, EXT_NONE, tcg_gen_addi_tl);
231}
232
233static void gen_slt(TCGv ret, TCGv s1, TCGv s2)
234{
235    tcg_gen_setcond_tl(TCG_COND_LT, ret, s1, s2);
236}
237
238static void gen_sltu(TCGv ret, TCGv s1, TCGv s2)
239{
240    tcg_gen_setcond_tl(TCG_COND_LTU, ret, s1, s2);
241}
242
243static bool trans_slti(DisasContext *ctx, arg_slti *a)
244{
245    return gen_arith_imm_tl(ctx, a, EXT_SIGN, gen_slt);
246}
247
248static bool trans_sltiu(DisasContext *ctx, arg_sltiu *a)
249{
250    return gen_arith_imm_tl(ctx, a, EXT_SIGN, gen_sltu);
251}
252
253static bool trans_xori(DisasContext *ctx, arg_xori *a)
254{
255    return gen_arith_imm_fn(ctx, a, EXT_NONE, tcg_gen_xori_tl);
256}
257
258static bool trans_ori(DisasContext *ctx, arg_ori *a)
259{
260    return gen_arith_imm_fn(ctx, a, EXT_NONE, tcg_gen_ori_tl);
261}
262
263static bool trans_andi(DisasContext *ctx, arg_andi *a)
264{
265    return gen_arith_imm_fn(ctx, a, EXT_NONE, tcg_gen_andi_tl);
266}
267
268static bool trans_slli(DisasContext *ctx, arg_slli *a)
269{
270    return gen_shift_imm_fn(ctx, a, EXT_NONE, tcg_gen_shli_tl);
271}
272
273static void gen_srliw(TCGv dst, TCGv src, target_long shamt)
274{
275    tcg_gen_extract_tl(dst, src, shamt, 32 - shamt);
276}
277
278static bool trans_srli(DisasContext *ctx, arg_srli *a)
279{
280    return gen_shift_imm_fn_per_ol(ctx, a, EXT_NONE,
281                                   tcg_gen_shri_tl, gen_srliw);
282}
283
284static void gen_sraiw(TCGv dst, TCGv src, target_long shamt)
285{
286    tcg_gen_sextract_tl(dst, src, shamt, 32 - shamt);
287}
288
289static bool trans_srai(DisasContext *ctx, arg_srai *a)
290{
291    return gen_shift_imm_fn_per_ol(ctx, a, EXT_NONE,
292                                   tcg_gen_sari_tl, gen_sraiw);
293}
294
295static bool trans_add(DisasContext *ctx, arg_add *a)
296{
297    return gen_arith(ctx, a, EXT_NONE, tcg_gen_add_tl);
298}
299
300static bool trans_sub(DisasContext *ctx, arg_sub *a)
301{
302    return gen_arith(ctx, a, EXT_NONE, tcg_gen_sub_tl);
303}
304
305static bool trans_sll(DisasContext *ctx, arg_sll *a)
306{
307    return gen_shift(ctx, a, EXT_NONE, tcg_gen_shl_tl);
308}
309
310static bool trans_slt(DisasContext *ctx, arg_slt *a)
311{
312    return gen_arith(ctx, a, EXT_SIGN, gen_slt);
313}
314
315static bool trans_sltu(DisasContext *ctx, arg_sltu *a)
316{
317    return gen_arith(ctx, a, EXT_SIGN, gen_sltu);
318}
319
320static bool trans_xor(DisasContext *ctx, arg_xor *a)
321{
322    return gen_arith(ctx, a, EXT_NONE, tcg_gen_xor_tl);
323}
324
325static bool trans_srl(DisasContext *ctx, arg_srl *a)
326{
327    return gen_shift(ctx, a, EXT_ZERO, tcg_gen_shr_tl);
328}
329
330static bool trans_sra(DisasContext *ctx, arg_sra *a)
331{
332    return gen_shift(ctx, a, EXT_SIGN, tcg_gen_sar_tl);
333}
334
335static bool trans_or(DisasContext *ctx, arg_or *a)
336{
337    return gen_arith(ctx, a, EXT_NONE, tcg_gen_or_tl);
338}
339
340static bool trans_and(DisasContext *ctx, arg_and *a)
341{
342    return gen_arith(ctx, a, EXT_NONE, tcg_gen_and_tl);
343}
344
345static bool trans_addiw(DisasContext *ctx, arg_addiw *a)
346{
347    REQUIRE_64BIT(ctx);
348    ctx->ol = MXL_RV32;
349    return gen_arith_imm_fn(ctx, a, EXT_NONE, tcg_gen_addi_tl);
350}
351
352static bool trans_slliw(DisasContext *ctx, arg_slliw *a)
353{
354    REQUIRE_64BIT(ctx);
355    ctx->ol = MXL_RV32;
356    return gen_shift_imm_fn(ctx, a, EXT_NONE, tcg_gen_shli_tl);
357}
358
359static bool trans_srliw(DisasContext *ctx, arg_srliw *a)
360{
361    REQUIRE_64BIT(ctx);
362    ctx->ol = MXL_RV32;
363    return gen_shift_imm_fn(ctx, a, EXT_NONE, gen_srliw);
364}
365
366static bool trans_sraiw(DisasContext *ctx, arg_sraiw *a)
367{
368    REQUIRE_64BIT(ctx);
369    ctx->ol = MXL_RV32;
370    return gen_shift_imm_fn(ctx, a, EXT_NONE, gen_sraiw);
371}
372
373static bool trans_addw(DisasContext *ctx, arg_addw *a)
374{
375    REQUIRE_64BIT(ctx);
376    ctx->ol = MXL_RV32;
377    return gen_arith(ctx, a, EXT_NONE, tcg_gen_add_tl);
378}
379
380static bool trans_subw(DisasContext *ctx, arg_subw *a)
381{
382    REQUIRE_64BIT(ctx);
383    ctx->ol = MXL_RV32;
384    return gen_arith(ctx, a, EXT_NONE, tcg_gen_sub_tl);
385}
386
387static bool trans_sllw(DisasContext *ctx, arg_sllw *a)
388{
389    REQUIRE_64BIT(ctx);
390    ctx->ol = MXL_RV32;
391    return gen_shift(ctx, a, EXT_NONE, tcg_gen_shl_tl);
392}
393
394static bool trans_srlw(DisasContext *ctx, arg_srlw *a)
395{
396    REQUIRE_64BIT(ctx);
397    ctx->ol = MXL_RV32;
398    return gen_shift(ctx, a, EXT_ZERO, tcg_gen_shr_tl);
399}
400
401static bool trans_sraw(DisasContext *ctx, arg_sraw *a)
402{
403    REQUIRE_64BIT(ctx);
404    ctx->ol = MXL_RV32;
405    return gen_shift(ctx, a, EXT_SIGN, tcg_gen_sar_tl);
406}
407
408static bool trans_fence(DisasContext *ctx, arg_fence *a)
409{
410    /* FENCE is a full memory barrier. */
411    tcg_gen_mb(TCG_MO_ALL | TCG_BAR_SC);
412    return true;
413}
414
415static bool trans_fence_i(DisasContext *ctx, arg_fence_i *a)
416{
417    if (!ctx->ext_ifencei) {
418        return false;
419    }
420
421    /*
422     * FENCE_I is a no-op in QEMU,
423     * however we need to end the translation block
424     */
425    tcg_gen_movi_tl(cpu_pc, ctx->pc_succ_insn);
426    tcg_gen_exit_tb(NULL, 0);
427    ctx->base.is_jmp = DISAS_NORETURN;
428    return true;
429}
430
431static bool do_csr_post(DisasContext *ctx)
432{
433    /* We may have changed important cpu state -- exit to main loop. */
434    tcg_gen_movi_tl(cpu_pc, ctx->pc_succ_insn);
435    tcg_gen_exit_tb(NULL, 0);
436    ctx->base.is_jmp = DISAS_NORETURN;
437    return true;
438}
439
440static bool do_csrr(DisasContext *ctx, int rd, int rc)
441{
442    TCGv dest = dest_gpr(ctx, rd);
443    TCGv_i32 csr = tcg_constant_i32(rc);
444
445    if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
446        gen_io_start();
447    }
448    gen_helper_csrr(dest, cpu_env, csr);
449    gen_set_gpr(ctx, rd, dest);
450    return do_csr_post(ctx);
451}
452
453static bool do_csrw(DisasContext *ctx, int rc, TCGv src)
454{
455    TCGv_i32 csr = tcg_constant_i32(rc);
456
457    if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
458        gen_io_start();
459    }
460    gen_helper_csrw(cpu_env, csr, src);
461    return do_csr_post(ctx);
462}
463
464static bool do_csrrw(DisasContext *ctx, int rd, int rc, TCGv src, TCGv mask)
465{
466    TCGv dest = dest_gpr(ctx, rd);
467    TCGv_i32 csr = tcg_constant_i32(rc);
468
469    if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
470        gen_io_start();
471    }
472    gen_helper_csrrw(dest, cpu_env, csr, src, mask);
473    gen_set_gpr(ctx, rd, dest);
474    return do_csr_post(ctx);
475}
476
477static bool trans_csrrw(DisasContext *ctx, arg_csrrw *a)
478{
479    TCGv src = get_gpr(ctx, a->rs1, EXT_NONE);
480
481    /*
482     * If rd == 0, the insn shall not read the csr, nor cause any of the
483     * side effects that might occur on a csr read.
484     */
485    if (a->rd == 0) {
486        return do_csrw(ctx, a->csr, src);
487    }
488
489    TCGv mask = tcg_constant_tl(-1);
490    return do_csrrw(ctx, a->rd, a->csr, src, mask);
491}
492
493static bool trans_csrrs(DisasContext *ctx, arg_csrrs *a)
494{
495    /*
496     * If rs1 == 0, the insn shall not write to the csr at all, nor
497     * cause any of the side effects that might occur on a csr write.
498     * Note that if rs1 specifies a register other than x0, holding
499     * a zero value, the instruction will still attempt to write the
500     * unmodified value back to the csr and will cause side effects.
501     */
502    if (a->rs1 == 0) {
503        return do_csrr(ctx, a->rd, a->csr);
504    }
505
506    TCGv ones = tcg_constant_tl(-1);
507    TCGv mask = get_gpr(ctx, a->rs1, EXT_ZERO);
508    return do_csrrw(ctx, a->rd, a->csr, ones, mask);
509}
510
511static bool trans_csrrc(DisasContext *ctx, arg_csrrc *a)
512{
513    /*
514     * If rs1 == 0, the insn shall not write to the csr at all, nor
515     * cause any of the side effects that might occur on a csr write.
516     * Note that if rs1 specifies a register other than x0, holding
517     * a zero value, the instruction will still attempt to write the
518     * unmodified value back to the csr and will cause side effects.
519     */
520    if (a->rs1 == 0) {
521        return do_csrr(ctx, a->rd, a->csr);
522    }
523
524    TCGv mask = get_gpr(ctx, a->rs1, EXT_ZERO);
525    return do_csrrw(ctx, a->rd, a->csr, ctx->zero, mask);
526}
527
528static bool trans_csrrwi(DisasContext *ctx, arg_csrrwi *a)
529{
530    TCGv src = tcg_constant_tl(a->rs1);
531
532    /*
533     * If rd == 0, the insn shall not read the csr, nor cause any of the
534     * side effects that might occur on a csr read.
535     */
536    if (a->rd == 0) {
537        return do_csrw(ctx, a->csr, src);
538    }
539
540    TCGv mask = tcg_constant_tl(-1);
541    return do_csrrw(ctx, a->rd, a->csr, src, mask);
542}
543
544static bool trans_csrrsi(DisasContext *ctx, arg_csrrsi *a)
545{
546    /*
547     * If rs1 == 0, the insn shall not write to the csr at all, nor
548     * cause any of the side effects that might occur on a csr write.
549     * Note that if rs1 specifies a register other than x0, holding
550     * a zero value, the instruction will still attempt to write the
551     * unmodified value back to the csr and will cause side effects.
552     */
553    if (a->rs1 == 0) {
554        return do_csrr(ctx, a->rd, a->csr);
555    }
556
557    TCGv ones = tcg_constant_tl(-1);
558    TCGv mask = tcg_constant_tl(a->rs1);
559    return do_csrrw(ctx, a->rd, a->csr, ones, mask);
560}
561
562static bool trans_csrrci(DisasContext *ctx, arg_csrrci *a)
563{
564    /*
565     * If rs1 == 0, the insn shall not write to the csr at all, nor
566     * cause any of the side effects that might occur on a csr write.
567     * Note that if rs1 specifies a register other than x0, holding
568     * a zero value, the instruction will still attempt to write the
569     * unmodified value back to the csr and will cause side effects.
570     */
571    if (a->rs1 == 0) {
572        return do_csrr(ctx, a->rd, a->csr);
573    }
574
575    TCGv mask = tcg_constant_tl(a->rs1);
576    return do_csrrw(ctx, a->rd, a->csr, ctx->zero, mask);
577}
578