static void gen_goto_tb(DisasContext *dc, int n, target_ulong dest)
{
if (use_goto_tb(dc, dest)) {
tcg_gen_goto_tb(n);
tcg_gen_movi_tl(cpu_pc, dest);
tcg_gen_exit_tb((uintptr_t)dc->tb + n);
} else {
tcg_gen_movi_tl(cpu_pc, dest);
if (dc->singlestep_enabled) {
t_gen_raise_exception(dc, EXCP_DEBUG);
}
tcg_gen_exit_tb(0);
}
}
static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a)
{
generate_exception(ctx, RISCV_EXCP_BREAKPOINT);
tcg_gen_exit_tb(NULL, 0); /* no chaining */
ctx->base.is_jmp = DISAS_NORETURN;
return true;
}
static bool trans_ecall(DisasContext *ctx, arg_ecall *a)
{
/* always generates U-level ECALL, fixed in do_interrupt handler */
generate_exception(ctx, RISCV_EXCP_U_ECALL);
tcg_gen_exit_tb(NULL, 0); /* no chaining */
ctx->base.is_jmp = DISAS_NORETURN;
return true;
}
static void gen_goto_tb(DisasContext *dc, int n, target_ulong dest)
{
TranslationBlock *tb;
tb = dc->tb;
if ((tb->pc & TARGET_PAGE_MASK) == (dest & TARGET_PAGE_MASK) &&
likely(!dc->singlestep_enabled)) {
tcg_gen_goto_tb(n);
tcg_gen_movi_tl(cpu_pc, dest);
tcg_gen_exit_tb((uintptr_t)tb + n);
} else {
tcg_gen_movi_tl(cpu_pc, dest);
if (dc->singlestep_enabled) {
t_gen_raise_exception(dc, EXCP_DEBUG);
}
tcg_gen_exit_tb(0);
}
}
static bool trans_mret(DisasContext *ctx, arg_mret *a)
{
#ifndef CONFIG_USER_ONLY
tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next);
gen_helper_mret(cpu_pc, cpu_env, cpu_pc);
tcg_gen_exit_tb(NULL, 0); /* no chaining */
ctx->base.is_jmp = DISAS_NORETURN;
return true;
#else
return false;
#endif
}
/* generate intermediate code for basic block 'tb'. */
static void gen_intermediate_code_internal(
CPUNios2State *env, TranslationBlock *tb, int search_pc)
{
DisasContext dc1, *dc = &dc1;
int num_insns;
int max_insns;
uint32_t next_page_start;
int j, lj = -1;
uint16_t *gen_opc_end = gen_opc_buf + OPC_MAX_SIZE;
/* Initialize DC */
dc->env = env;
dc->cpu_R = cpu_R;
dc->is_jmp = DISAS_NEXT;
dc->pc = tb->pc;
dc->tb = tb;
/* Dump the CPU state to the log */
if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)) {
qemu_log("--------------\n");
log_cpu_state(env, 0);
}
/* Set up instruction counts */
num_insns = 0;
max_insns = tb->cflags & CF_COUNT_MASK;
if (max_insns == 0) {
max_insns = CF_COUNT_MASK;
}
next_page_start = (tb->pc & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
gen_icount_start();
do {
/* Mark instruction start with associated PC */
if (search_pc) {
j = gen_opc_ptr - gen_opc_buf;
if (lj < j) {
lj++;
while (lj < j) {
gen_opc_instr_start[lj++] = 0;
}
}
gen_opc_pc[lj] = dc->pc;
gen_opc_instr_start[lj] = 1;
gen_opc_icount[lj] = num_insns;
}
LOG_DIS("%8.8x:\t", dc->pc);
if (num_insns + 1 == max_insns && (tb->cflags & CF_LAST_IO)) {
gen_io_start();
}
/* Decode an instruction */
handle_instruction(dc);
dc->pc += 4;
num_insns++;
/* Translation stops when a conditional branch is encountered.
* Otherwise the subsequent code could get translated several times.
* Also stop translation when a page boundary is reached. This
* ensures prefetch aborts occur at the right place. */
} while (!dc->is_jmp && gen_opc_ptr < gen_opc_end &&
!env->singlestep_enabled &&
!singlestep &&
dc->pc < next_page_start &&
num_insns < max_insns);
if (tb->cflags & CF_LAST_IO) {
gen_io_end();
}
/* Indicate where the next block should start */
switch (dc->is_jmp) {
case DISAS_NEXT:
/* Save the current PC back into the CPU register */
tcg_gen_movi_tl(cpu_R[R_PC], dc->pc);
tcg_gen_exit_tb(0);
break;
default:
case DISAS_JUMP:
case DISAS_UPDATE:
/* The jump will already have updated the PC register */
tcg_gen_exit_tb(0);
break;
case DISAS_TB_JUMP:
/* nothing more to generate */
break;
}
/* End off the block */
gen_icount_end(tb, num_insns);
*gen_opc_ptr = INDEX_op_end;
/* Mark instruction starts for the final generated instruction */
if (search_pc) {
j = gen_opc_ptr - gen_opc_buf;
lj++;
while (lj <= j) {
gen_opc_instr_start[lj++] = 0;
}
} else {
tb->size = dc->pc - tb->pc;
tb->icount = num_insns;
}
#ifdef DEBUG_DISAS
if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)) {
qemu_log("----------------\n");
qemu_log("IN: %s\n", lookup_symbol(tb->pc));
log_target_disas(tb->pc, dc->pc - tb->pc, 0);
qemu_log("\nisize=%d osize=%td\n",
dc->pc - tb->pc, gen_opc_ptr - gen_opc_buf);
}
#endif
}
/* generate intermediate code for basic block 'tb'. */
void gen_intermediate_code(CPULM32State *env, struct TranslationBlock *tb)
{
LM32CPU *cpu = lm32_env_get_cpu(env);
CPUState *cs = CPU(cpu);
struct DisasContext ctx, *dc = &ctx;
uint32_t pc_start;
uint32_t next_page_start;
int num_insns;
int max_insns;
pc_start = tb->pc;
dc->features = cpu->features;
dc->num_breakpoints = cpu->num_breakpoints;
dc->num_watchpoints = cpu->num_watchpoints;
dc->tb = tb;
dc->is_jmp = DISAS_NEXT;
dc->pc = pc_start;
dc->singlestep_enabled = cs->singlestep_enabled;
if (pc_start & 3) {
qemu_log_mask(LOG_GUEST_ERROR,
"unaligned PC=%x. Ignoring lowest bits.\n", pc_start);
pc_start &= ~3;
}
next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
num_insns = 0;
max_insns = tb->cflags & CF_COUNT_MASK;
if (max_insns == 0) {
max_insns = CF_COUNT_MASK;
}
if (max_insns > TCG_MAX_INSNS) {
max_insns = TCG_MAX_INSNS;
}
gen_tb_start(tb);
do {
tcg_gen_insn_start(dc->pc);
num_insns++;
if (unlikely(cpu_breakpoint_test(cs, dc->pc, BP_ANY))) {
tcg_gen_movi_tl(cpu_pc, dc->pc);
t_gen_raise_exception(dc, EXCP_DEBUG);
dc->is_jmp = DISAS_UPDATE;
/* The address covered by the breakpoint must be included in
[tb->pc, tb->pc + tb->size) in order to for it to be
properly cleared -- thus we increment the PC here so that
the logic setting tb->size below does the right thing. */
dc->pc += 4;
break;
}
/* Pretty disas. */
LOG_DIS("%8.8x:\t", dc->pc);
if (num_insns == max_insns && (tb->cflags & CF_LAST_IO)) {
gen_io_start();
}
decode(dc, cpu_ldl_code(env, dc->pc));
dc->pc += 4;
} while (!dc->is_jmp
&& !tcg_op_buf_full()
&& !cs->singlestep_enabled
&& !singlestep
&& (dc->pc < next_page_start)
&& num_insns < max_insns);
if (tb->cflags & CF_LAST_IO) {
gen_io_end();
}
if (unlikely(cs->singlestep_enabled)) {
if (dc->is_jmp == DISAS_NEXT) {
tcg_gen_movi_tl(cpu_pc, dc->pc);
}
t_gen_raise_exception(dc, EXCP_DEBUG);
} else {
switch (dc->is_jmp) {
case DISAS_NEXT:
gen_goto_tb(dc, 1, dc->pc);
break;
default:
case DISAS_JUMP:
case DISAS_UPDATE:
/* indicate that the hash table must be used
to find the next TB */
tcg_gen_exit_tb(0);
break;
case DISAS_TB_JUMP:
/* nothing more to generate */
break;
}
}
gen_tb_end(tb, num_insns);
tb->size = dc->pc - pc_start;
tb->icount = num_insns;
#ifdef DEBUG_DISAS
if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)) {
qemu_log("\n");
log_target_disas(cs, pc_start, dc->pc - pc_start, 0);
qemu_log("\nisize=%d osize=%d\n",
dc->pc - pc_start, tcg_op_buf_count());
}
#endif
}
