/*
* Generic intermediate code generation.
*
* Copyright (C) 2016-2017 Lluís Vilanova <vilanova@ac.upc.edu>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/error-report.h"
#include "tcg/tcg.h"
#include "tcg/tcg-op.h"
#include "exec/exec-all.h"
#include "exec/gen-icount.h"
#include "exec/log.h"
#include "exec/translator.h"
#include "exec/plugin-gen.h"
#include "sysemu/replay.h"
/* Pairs with tcg_clear_temp_count.
To be called by #TranslatorOps.{translate_insn,tb_stop} if
(1) the target is sufficiently clean to support reporting,
(2) as and when all temporaries are known to be consumed.
For most targets, (2) is at the end of translate_insn. */
void translator_loop_temp_check(DisasContextBase *db)
{
if (tcg_check_temp_count()) {
qemu_log("warning: TCG temporary leaks before "
TARGET_FMT_lx "\n", db->pc_next);
}
}
bool translator_use_goto_tb(DisasContextBase *db, target_ulong dest)
{
/* Suppress goto_tb if requested. */
if (tb_cflags(db->tb) & CF_NO_GOTO_TB) {
return false;
}
/* Check for the dest on the same page as the start of the TB. */
return ((db->pc_first ^ dest) & TARGET_PAGE_MASK) == 0;
}
void translator_loop(CPUState *cpu, TranslationBlock *tb, int max_insns,
target_ulong pc, void *host_pc,
const TranslatorOps *ops, DisasContextBase *db)
{
uint32_t cflags = tb_cflags(tb);
bool plugin_enabled;
/* Initialize DisasContext */
db->tb = tb;
db->pc_first = pc;
db->pc_next = pc;
db->is_jmp = DISAS_NEXT;
db->num_insns = 0;
db->max_insns = max_insns;
db->singlestep_enabled = cflags & CF_SINGLE_STEP;
db->host_addr[0] = host_pc;
db->host_addr[1] = NULL;
#ifdef CONFIG_USER_ONLY
page_protect(pc);
#endif
ops->init_disas_context(db, cpu);
tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
/* Reset the temp count so that we can identify leaks */
tcg_clear_temp_count();
/* Start translating. */
gen_tb_start(db->tb);
ops->tb_start(db, cpu);
tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
plugin_enabled = plugin_gen_tb_start(cpu, db, cflags & CF_MEMI_ONLY);
while (true) {
db->num_insns++;
ops->insn_start(db, cpu);
tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
if (plugin_enabled) {
plugin_gen_insn_start(cpu, db);
}
/* Disassemble one instruction. The translate_insn hook should
update db->pc_next and db->is_jmp to indicate what should be
done next -- either exiting this loop or locate the start of
the next instruction. */
if (db->num_insns == db->max_insns && (cflags & CF_LAST_IO)) {
/* Accept I/O on the last instruction. */
gen_io_start();
ops->translate_insn(db, cpu);
} else {
/* we should only see CF_MEMI_ONLY for io_recompile */
tcg_debug_assert(!(cflags & CF_MEMI_ONLY));
ops->translate_insn(db, cpu);
}
/* Stop translation if translate_insn so indicated. */
if (db->is_jmp != DISAS_NEXT) {
break;
}
/*
* We can't instrument after instructions that change control
* flow although this only really affects post-load operations.
*/
if (plugin_enabled) {
plugin_gen_insn_end();
}
/* Stop translation if the output buffer is full,
or we have executed all of the allowed instructions. */
if (tcg_op_buf_full() || db->num_insns >= db->max_insns) {
db->is_jmp = DISAS_TOO_MANY;
break;
}
}
/* Emit code to exit the TB, as indicated by db->is_jmp. */
ops->tb_stop(db, cpu);
gen_tb_end(db->tb, db->num_insns);
if (plugin_enabled) {
plugin_gen_tb_end(cpu);
}
/* The disas_log hook may use these values rather than recompute. */
tb->size = db->pc_next - db->pc_first;
tb->icount = db->num_insns;
#ifdef DEBUG_DISAS
if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
&& qemu_log_in_addr_range(db->pc_first)) {
FILE *logfile = qemu_log_trylock();
if (logfile) {
fprintf(logfile, "----------------\n");
ops->disas_log(db, cpu, logfile);
fprintf(logfile, "\n");
qemu_log_unlock(logfile);
}
}
#endif
}
static void *translator_access(CPUArchState *env, DisasContextBase *db,
target_ulong pc, size_t len)
{
void *host;
target_ulong base, end;
TranslationBlock *tb;
tb = db->tb;
/* Use slow path if first page is MMIO. */
if (unlikely(tb_page_addr0(tb) == -1)) {
return NULL;
}
end = pc + len - 1;
if (likely(is_same_page(db, end))) {
host = db->host_addr[0];
base = db->pc_first;
} else {
host = db->host_addr[1];
base = TARGET_PAGE_ALIGN(db->pc_first);
if (host == NULL) {
tb_page_addr_t phys_page =
get_page_addr_code_hostp(env, base, &db->host_addr[1]);
/* We cannot handle MMIO as second page. */
assert(phys_page != -1);
tb_set_page_addr1(tb, phys_page);
#ifdef CONFIG_USER_ONLY
page_protect(end);
#endif
host = db->host_addr[1];
}
/* Use slow path when crossing pages. */
if (is_same_page(db, pc)) {
return NULL;
}
}
tcg_debug_assert(pc >= base);
return host + (pc - base);
}
uint8_t translator_ldub(CPUArchState *env, DisasContextBase *db, abi_ptr pc)
{
uint8_t ret;
void *p = translator_access(env, db, pc, sizeof(ret));
if (p) {
plugin_insn_append(pc, p, sizeof(ret));
return ldub_p(p);
}
ret = cpu_ldub_code(env, pc);
plugin_insn_append(pc, &ret, sizeof(ret));
return ret;
}
uint16_t translator_lduw(CPUArchState *env, DisasContextBase *db, abi_ptr pc)
{
uint16_t ret, plug;
void *p = translator_access(env, db, pc, sizeof(ret));
if (p) {
plugin_insn_append(pc, p, sizeof(ret));
return lduw_p(p);
}
ret = cpu_lduw_code(env, pc);
plug = tswap16(ret);
plugin_insn_append(pc, &plug, sizeof(ret));
return ret;
}
uint32_t translator_ldl(CPUArchState *env, DisasContextBase *db, abi_ptr pc)
{
uint32_t ret, plug;
void *p = translator_access(env, db, pc, sizeof(ret));
if (p) {
plugin_insn_append(pc, p, sizeof(ret));
return ldl_p(p);
}
ret = cpu_ldl_code(env, pc);
plug = tswap32(ret);
plugin_insn_append(pc, &plug, sizeof(ret));
return ret;
}
uint64_t translator_ldq(CPUArchState *env, DisasContextBase *db, abi_ptr pc)
{
uint64_t ret, plug;
void *p = translator_access(env, db, pc, sizeof(ret));
if (p) {
plugin_insn_append(pc, p, sizeof(ret));
return ldq_p(p);
}
ret = cpu_ldq_code(env, pc);
plug = tswap64(ret);
plugin_insn_append(pc, &plug, sizeof(ret));
return ret;
}
