target/arm: Implement VFP fp16 for VABS, VNEG, VSQRT
[qemu.git] / accel / tcg / translator.c
1 /*
2 * Generic intermediate code generation.
3 *
4 * Copyright (C) 2016-2017 LluĂ­s Vilanova <vilanova@ac.upc.edu>
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
7 * See the COPYING file in the top-level directory.
8 */
9
10 #include "qemu/osdep.h"
11 #include "qemu/error-report.h"
12 #include "cpu.h"
13 #include "tcg/tcg.h"
14 #include "tcg/tcg-op.h"
15 #include "exec/exec-all.h"
16 #include "exec/gen-icount.h"
17 #include "exec/log.h"
18 #include "exec/translator.h"
19 #include "exec/plugin-gen.h"
20
21 /* Pairs with tcg_clear_temp_count.
22 To be called by #TranslatorOps.{translate_insn,tb_stop} if
23 (1) the target is sufficiently clean to support reporting,
24 (2) as and when all temporaries are known to be consumed.
25 For most targets, (2) is at the end of translate_insn. */
26 void translator_loop_temp_check(DisasContextBase *db)
27 {
28 if (tcg_check_temp_count()) {
29 qemu_log("warning: TCG temporary leaks before "
30 TARGET_FMT_lx "\n", db->pc_next);
31 }
32 }
33
34 void translator_loop(const TranslatorOps *ops, DisasContextBase *db,
35 CPUState *cpu, TranslationBlock *tb, int max_insns)
36 {
37 int bp_insn = 0;
38 bool plugin_enabled;
39
40 /* Initialize DisasContext */
41 db->tb = tb;
42 db->pc_first = tb->pc;
43 db->pc_next = db->pc_first;
44 db->is_jmp = DISAS_NEXT;
45 db->num_insns = 0;
46 db->max_insns = max_insns;
47 db->singlestep_enabled = cpu->singlestep_enabled;
48
49 ops->init_disas_context(db, cpu);
50 tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
51
52 /* Reset the temp count so that we can identify leaks */
53 tcg_clear_temp_count();
54
55 /* Start translating. */
56 gen_tb_start(db->tb);
57 ops->tb_start(db, cpu);
58 tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
59
60 plugin_enabled = plugin_gen_tb_start(cpu, tb);
61
62 while (true) {
63 db->num_insns++;
64 ops->insn_start(db, cpu);
65 tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
66
67 if (plugin_enabled) {
68 plugin_gen_insn_start(cpu, db);
69 }
70
71 /* Pass breakpoint hits to target for further processing */
72 if (!db->singlestep_enabled
73 && unlikely(!QTAILQ_EMPTY(&cpu->breakpoints))) {
74 CPUBreakpoint *bp;
75 QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
76 if (bp->pc == db->pc_next) {
77 if (ops->breakpoint_check(db, cpu, bp)) {
78 bp_insn = 1;
79 break;
80 }
81 }
82 }
83 /* The breakpoint_check hook may use DISAS_TOO_MANY to indicate
84 that only one more instruction is to be executed. Otherwise
85 it should use DISAS_NORETURN when generating an exception,
86 but may use a DISAS_TARGET_* value for Something Else. */
87 if (db->is_jmp > DISAS_TOO_MANY) {
88 break;
89 }
90 }
91
92 /* Disassemble one instruction. The translate_insn hook should
93 update db->pc_next and db->is_jmp to indicate what should be
94 done next -- either exiting this loop or locate the start of
95 the next instruction. */
96 if (db->num_insns == db->max_insns
97 && (tb_cflags(db->tb) & CF_LAST_IO)) {
98 /* Accept I/O on the last instruction. */
99 gen_io_start();
100 ops->translate_insn(db, cpu);
101 } else {
102 ops->translate_insn(db, cpu);
103 }
104
105 /* Stop translation if translate_insn so indicated. */
106 if (db->is_jmp != DISAS_NEXT) {
107 break;
108 }
109
110 /*
111 * We can't instrument after instructions that change control
112 * flow although this only really affects post-load operations.
113 */
114 if (plugin_enabled) {
115 plugin_gen_insn_end();
116 }
117
118 /* Stop translation if the output buffer is full,
119 or we have executed all of the allowed instructions. */
120 if (tcg_op_buf_full() || db->num_insns >= db->max_insns) {
121 db->is_jmp = DISAS_TOO_MANY;
122 break;
123 }
124 }
125
126 /* Emit code to exit the TB, as indicated by db->is_jmp. */
127 ops->tb_stop(db, cpu);
128 gen_tb_end(db->tb, db->num_insns - bp_insn);
129
130 if (plugin_enabled) {
131 plugin_gen_tb_end(cpu);
132 }
133
134 /* The disas_log hook may use these values rather than recompute. */
135 db->tb->size = db->pc_next - db->pc_first;
136 db->tb->icount = db->num_insns;
137
138 #ifdef DEBUG_DISAS
139 if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
140 && qemu_log_in_addr_range(db->pc_first)) {
141 FILE *logfile = qemu_log_lock();
142 qemu_log("----------------\n");
143 ops->disas_log(db, cpu);
144 qemu_log("\n");
145 qemu_log_unlock(logfile);
146 }
147 #endif
148 }