qemu-e2k/accel/tcg/translator.c

179 lines
5.7 KiB
C

/*
* 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;
}
static inline void translator_page_protect(DisasContextBase *dcbase,
target_ulong pc)
{
#ifdef CONFIG_USER_ONLY
dcbase->page_protect_end = pc | ~TARGET_PAGE_MASK;
page_protect(pc);
#endif
}
void translator_loop(const TranslatorOps *ops, DisasContextBase *db,
CPUState *cpu, TranslationBlock *tb, int max_insns)
{
uint32_t cflags = tb_cflags(tb);
bool plugin_enabled;
/* Initialize DisasContext */
db->tb = tb;
db->pc_first = tb->pc;
db->pc_next = db->pc_first;
db->is_jmp = DISAS_NEXT;
db->num_insns = 0;
db->max_insns = max_insns;
db->singlestep_enabled = cflags & CF_SINGLE_STEP;
translator_page_protect(db, db->pc_next);
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, tb, 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_lock();
qemu_log("----------------\n");
ops->disas_log(db, cpu);
qemu_log("\n");
qemu_log_unlock(logfile);
}
#endif
}
static inline void translator_maybe_page_protect(DisasContextBase *dcbase,
target_ulong pc, size_t len)
{
#ifdef CONFIG_USER_ONLY
target_ulong end = pc + len - 1;
if (end > dcbase->page_protect_end) {
translator_page_protect(dcbase, end);
}
#endif
}
#define GEN_TRANSLATOR_LD(fullname, type, load_fn, swap_fn) \
type fullname ## _swap(CPUArchState *env, DisasContextBase *dcbase, \
abi_ptr pc, bool do_swap) \
{ \
translator_maybe_page_protect(dcbase, pc, sizeof(type)); \
type ret = load_fn(env, pc); \
if (do_swap) { \
ret = swap_fn(ret); \
} \
plugin_insn_append(&ret, sizeof(ret)); \
return ret; \
}
FOR_EACH_TRANSLATOR_LD(GEN_TRANSLATOR_LD)
#undef GEN_TRANSLATOR_LD