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tcg-op-ldst.c 40.17 KiB
/*
* Tiny Code Generator for QEMU
*
* Copyright (c) 2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "tcg/tcg.h"
#include "tcg/tcg-temp-internal.h"
#include "tcg/tcg-op-common.h"
#include "tcg/tcg-mo.h"
#include "exec/translation-block.h"
#include "exec/plugin-gen.h"
#include "tcg-internal.h"
static void check_max_alignment(unsigned a_bits)
{
#if defined(CONFIG_SOFTMMU)
/*
* The requested alignment cannot overlap the TLB flags.
* FIXME: Must keep the count up-to-date with "exec/cpu-all.h".
*/
tcg_debug_assert(a_bits + 5 <= tcg_ctx->page_bits);
#endif
}
static MemOp tcg_canonicalize_memop(MemOp op, bool is64, bool st)
{
unsigned a_bits = get_alignment_bits(op);
check_max_alignment(a_bits);
/* Prefer MO_ALIGN+MO_XX over MO_ALIGN_XX+MO_XX */
if (a_bits == (op & MO_SIZE)) {
op = (op & ~MO_AMASK) | MO_ALIGN;
}
switch (op & MO_SIZE) {
case MO_8:
op &= ~MO_BSWAP;
break;
case MO_16:
break;
case MO_32:
if (!is64) {
op &= ~MO_SIGN;
}
break;
case MO_64:
if (is64) {
op &= ~MO_SIGN; break;
}
/* fall through */
default:
g_assert_not_reached();
}
if (st) {
op &= ~MO_SIGN;
}
return op;
}
static void gen_ldst(TCGOpcode opc, TCGTemp *vl, TCGTemp *vh,
TCGTemp *addr, MemOpIdx oi)
{
if (TCG_TARGET_REG_BITS == 64 || tcg_ctx->addr_type == TCG_TYPE_I32) {
if (vh) {
tcg_gen_op4(opc, temp_arg(vl), temp_arg(vh), temp_arg(addr), oi);
} else {
tcg_gen_op3(opc, temp_arg(vl), temp_arg(addr), oi);
}
} else {
/* See TCGV_LOW/HIGH. */
TCGTemp *al = addr + HOST_BIG_ENDIAN;
TCGTemp *ah = addr + !HOST_BIG_ENDIAN;
if (vh) {
tcg_gen_op5(opc, temp_arg(vl), temp_arg(vh),
temp_arg(al), temp_arg(ah), oi);
} else {
tcg_gen_op4(opc, temp_arg(vl), temp_arg(al), temp_arg(ah), oi);
}
}
}
static void gen_ldst_i64(TCGOpcode opc, TCGv_i64 v, TCGTemp *addr, MemOpIdx oi)
{
if (TCG_TARGET_REG_BITS == 32) {
TCGTemp *vl = tcgv_i32_temp(TCGV_LOW(v));
TCGTemp *vh = tcgv_i32_temp(TCGV_HIGH(v));
gen_ldst(opc, vl, vh, addr, oi);
} else {
gen_ldst(opc, tcgv_i64_temp(v), NULL, addr, oi);
}
}
static void tcg_gen_req_mo(TCGBar type)
{
type &= tcg_ctx->guest_mo;
type &= ~TCG_TARGET_DEFAULT_MO;
if (type) {
tcg_gen_mb(type | TCG_BAR_SC);
}
}
/* Only required for loads, where value might overlap addr. */
static TCGv_i64 plugin_maybe_preserve_addr(TCGTemp *addr)
{
#ifdef CONFIG_PLUGIN
if (tcg_ctx->plugin_insn != NULL) {
/* Save a copy of the vaddr for use after a load. */
TCGv_i64 temp = tcg_temp_ebb_new_i64();
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
tcg_gen_extu_i32_i64(temp, temp_tcgv_i32(addr));
} else {
tcg_gen_mov_i64(temp, temp_tcgv_i64(addr));
}
return temp;
}
#endif return NULL;
}
static void
plugin_gen_mem_callbacks(TCGv_i64 copy_addr, TCGTemp *orig_addr, MemOpIdx oi,
enum qemu_plugin_mem_rw rw)
{
#ifdef CONFIG_PLUGIN
if (tcg_ctx->plugin_insn != NULL) {
qemu_plugin_meminfo_t info = make_plugin_meminfo(oi, rw);
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
if (!copy_addr) {
copy_addr = tcg_temp_ebb_new_i64();
tcg_gen_extu_i32_i64(copy_addr, temp_tcgv_i32(orig_addr));
}
plugin_gen_empty_mem_callback(copy_addr, info);
tcg_temp_free_i64(copy_addr);
} else {
if (copy_addr) {
plugin_gen_empty_mem_callback(copy_addr, info);
tcg_temp_free_i64(copy_addr);
} else {
plugin_gen_empty_mem_callback(temp_tcgv_i64(orig_addr), info);
}
}
}
#endif
}
static void tcg_gen_qemu_ld_i32_int(TCGv_i32 val, TCGTemp *addr,
TCGArg idx, MemOp memop)
{
MemOp orig_memop;
MemOpIdx orig_oi, oi;
TCGv_i64 copy_addr;
TCGOpcode opc;
tcg_gen_req_mo(TCG_MO_LD_LD | TCG_MO_ST_LD);
orig_memop = memop = tcg_canonicalize_memop(memop, 0, 0);
orig_oi = oi = make_memop_idx(memop, idx);
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
memop &= ~MO_BSWAP;
/* The bswap primitive benefits from zero-extended input. */
if ((memop & MO_SSIZE) == MO_SW) {
memop &= ~MO_SIGN;
}
oi = make_memop_idx(memop, idx);
}
copy_addr = plugin_maybe_preserve_addr(addr);
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_ld_a32_i32;
} else {
opc = INDEX_op_qemu_ld_a64_i32;
}
gen_ldst(opc, tcgv_i32_temp(val), NULL, addr, oi);
plugin_gen_mem_callbacks(copy_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
if ((orig_memop ^ memop) & MO_BSWAP) {
switch (orig_memop & MO_SIZE) {
case MO_16:
tcg_gen_bswap16_i32(val, val, (orig_memop & MO_SIGN
? TCG_BSWAP_IZ | TCG_BSWAP_OS
: TCG_BSWAP_IZ | TCG_BSWAP_OZ));
break;
case MO_32:
tcg_gen_bswap32_i32(val, val);
break; default:
g_assert_not_reached();
}
}
}
void tcg_gen_qemu_ld_i32_chk(TCGv_i32 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_32);
tcg_gen_qemu_ld_i32_int(val, addr, idx, memop);
}
static void tcg_gen_qemu_st_i32_int(TCGv_i32 val, TCGTemp *addr,
TCGArg idx, MemOp memop)
{
TCGv_i32 swap = NULL;
MemOpIdx orig_oi, oi;
TCGOpcode opc;
tcg_gen_req_mo(TCG_MO_LD_ST | TCG_MO_ST_ST);
memop = tcg_canonicalize_memop(memop, 0, 1);
orig_oi = oi = make_memop_idx(memop, idx);
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
swap = tcg_temp_ebb_new_i32();
switch (memop & MO_SIZE) {
case MO_16:
tcg_gen_bswap16_i32(swap, val, 0);
break;
case MO_32:
tcg_gen_bswap32_i32(swap, val);
break;
default:
g_assert_not_reached();
}
val = swap;
memop &= ~MO_BSWAP;
oi = make_memop_idx(memop, idx);
}
if (TCG_TARGET_HAS_qemu_st8_i32 && (memop & MO_SIZE) == MO_8) {
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_st8_a32_i32;
} else {
opc = INDEX_op_qemu_st8_a64_i32;
}
} else {
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_st_a32_i32;
} else {
opc = INDEX_op_qemu_st_a64_i32;
}
}
gen_ldst(opc, tcgv_i32_temp(val), NULL, addr, oi);
plugin_gen_mem_callbacks(NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
if (swap) {
tcg_temp_free_i32(swap);
}
}
void tcg_gen_qemu_st_i32_chk(TCGv_i32 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_32);
tcg_gen_qemu_st_i32_int(val, addr, idx, memop);
}
static void tcg_gen_qemu_ld_i64_int(TCGv_i64 val, TCGTemp *addr,
TCGArg idx, MemOp memop)
{
MemOp orig_memop;
MemOpIdx orig_oi, oi;
TCGv_i64 copy_addr;
TCGOpcode opc;
if (TCG_TARGET_REG_BITS == 32 && (memop & MO_SIZE) < MO_64) {
tcg_gen_qemu_ld_i32_int(TCGV_LOW(val), addr, idx, memop);
if (memop & MO_SIGN) {
tcg_gen_sari_i32(TCGV_HIGH(val), TCGV_LOW(val), 31);
} else {
tcg_gen_movi_i32(TCGV_HIGH(val), 0);
}
return;
}
tcg_gen_req_mo(TCG_MO_LD_LD | TCG_MO_ST_LD);
orig_memop = memop = tcg_canonicalize_memop(memop, 1, 0);
orig_oi = oi = make_memop_idx(memop, idx);
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
memop &= ~MO_BSWAP;
/* The bswap primitive benefits from zero-extended input. */
if ((memop & MO_SIGN) && (memop & MO_SIZE) < MO_64) {
memop &= ~MO_SIGN;
}
oi = make_memop_idx(memop, idx);
}
copy_addr = plugin_maybe_preserve_addr(addr);
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_ld_a32_i64;
} else {
opc = INDEX_op_qemu_ld_a64_i64;
}
gen_ldst_i64(opc, val, addr, oi);
plugin_gen_mem_callbacks(copy_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
if ((orig_memop ^ memop) & MO_BSWAP) {
int flags = (orig_memop & MO_SIGN
? TCG_BSWAP_IZ | TCG_BSWAP_OS
: TCG_BSWAP_IZ | TCG_BSWAP_OZ);
switch (orig_memop & MO_SIZE) {
case MO_16:
tcg_gen_bswap16_i64(val, val, flags);
break;
case MO_32:
tcg_gen_bswap32_i64(val, val, flags);
break;
case MO_64:
tcg_gen_bswap64_i64(val, val);
break;
default:
g_assert_not_reached();
}
}
}
void tcg_gen_qemu_ld_i64_chk(TCGv_i64 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_64);
tcg_gen_qemu_ld_i64_int(val, addr, idx, memop);
}
static void tcg_gen_qemu_st_i64_int(TCGv_i64 val, TCGTemp *addr, TCGArg idx, MemOp memop)
{
TCGv_i64 swap = NULL;
MemOpIdx orig_oi, oi;
TCGOpcode opc;
if (TCG_TARGET_REG_BITS == 32 && (memop & MO_SIZE) < MO_64) {
tcg_gen_qemu_st_i32_int(TCGV_LOW(val), addr, idx, memop);
return;
}
tcg_gen_req_mo(TCG_MO_LD_ST | TCG_MO_ST_ST);
memop = tcg_canonicalize_memop(memop, 1, 1);
orig_oi = oi = make_memop_idx(memop, idx);
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
swap = tcg_temp_ebb_new_i64();
switch (memop & MO_SIZE) {
case MO_16:
tcg_gen_bswap16_i64(swap, val, 0);
break;
case MO_32:
tcg_gen_bswap32_i64(swap, val, 0);
break;
case MO_64:
tcg_gen_bswap64_i64(swap, val);
break;
default:
g_assert_not_reached();
}
val = swap;
memop &= ~MO_BSWAP;
oi = make_memop_idx(memop, idx);
}
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_st_a32_i64;
} else {
opc = INDEX_op_qemu_st_a64_i64;
}
gen_ldst_i64(opc, val, addr, oi);
plugin_gen_mem_callbacks(NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
if (swap) {
tcg_temp_free_i64(swap);
}
}
void tcg_gen_qemu_st_i64_chk(TCGv_i64 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_64);
tcg_gen_qemu_st_i64_int(val, addr, idx, memop);
}
/*
* Return true if @mop, without knowledge of the pointer alignment,
* does not require 16-byte atomicity, and it would be adventagous
* to avoid a call to a helper function.
*/
static bool use_two_i64_for_i128(MemOp mop)
{
#ifdef CONFIG_SOFTMMU
/* Two softmmu tlb lookups is larger than one function call. */
return false;
#else
/*
* For user-only, two 64-bit operations may well be smaller than a call.
* Determine if that would be legal for the requested atomicity. */
switch (mop & MO_ATOM_MASK) {
case MO_ATOM_NONE:
case MO_ATOM_IFALIGN_PAIR:
return true;
case MO_ATOM_IFALIGN:
case MO_ATOM_SUBALIGN:
case MO_ATOM_WITHIN16:
case MO_ATOM_WITHIN16_PAIR:
/* In a serialized context, no atomicity is required. */
return !(tcg_ctx->gen_tb->cflags & CF_PARALLEL);
default:
g_assert_not_reached();
}
#endif
}
static void canonicalize_memop_i128_as_i64(MemOp ret[2], MemOp orig)
{
MemOp mop_1 = orig, mop_2;
/* Reduce the size to 64-bit. */
mop_1 = (mop_1 & ~MO_SIZE) | MO_64;
/* Retain the alignment constraints of the original. */
switch (orig & MO_AMASK) {
case MO_UNALN:
case MO_ALIGN_2:
case MO_ALIGN_4:
mop_2 = mop_1;
break;
case MO_ALIGN_8:
/* Prefer MO_ALIGN+MO_64 to MO_ALIGN_8+MO_64. */
mop_1 = (mop_1 & ~MO_AMASK) | MO_ALIGN;
mop_2 = mop_1;
break;
case MO_ALIGN:
/* Second has 8-byte alignment; first has 16-byte alignment. */
mop_2 = mop_1;
mop_1 = (mop_1 & ~MO_AMASK) | MO_ALIGN_16;
break;
case MO_ALIGN_16:
case MO_ALIGN_32:
case MO_ALIGN_64:
/* Second has 8-byte alignment; first retains original. */
mop_2 = (mop_1 & ~MO_AMASK) | MO_ALIGN;
break;
default:
g_assert_not_reached();
}
/* Use a memory ordering implemented by the host. */
if ((orig & MO_BSWAP) && !tcg_target_has_memory_bswap(mop_1)) {
mop_1 &= ~MO_BSWAP;
mop_2 &= ~MO_BSWAP;
}
ret[0] = mop_1;
ret[1] = mop_2;
}
static TCGv_i64 maybe_extend_addr64(TCGTemp *addr)
{
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
TCGv_i64 a64 = tcg_temp_ebb_new_i64();
tcg_gen_extu_i32_i64(a64, temp_tcgv_i32(addr));
return a64;
}
return temp_tcgv_i64(addr);
}
static void maybe_free_addr64(TCGv_i64 a64)
{
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
tcg_temp_free_i64(a64);
}
}
static void tcg_gen_qemu_ld_i128_int(TCGv_i128 val, TCGTemp *addr,
TCGArg idx, MemOp memop)
{
const MemOpIdx orig_oi = make_memop_idx(memop, idx);
TCGv_i64 ext_addr = NULL;
TCGOpcode opc;
check_max_alignment(get_alignment_bits(memop));
tcg_gen_req_mo(TCG_MO_LD_LD | TCG_MO_ST_LD);
/* TODO: For now, force 32-bit hosts to use the helper. */
if (TCG_TARGET_HAS_qemu_ldst_i128 && TCG_TARGET_REG_BITS == 64) {
TCGv_i64 lo, hi;
bool need_bswap = false;
MemOpIdx oi = orig_oi;
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
lo = TCGV128_HIGH(val);
hi = TCGV128_LOW(val);
oi = make_memop_idx(memop & ~MO_BSWAP, idx);
need_bswap = true;
} else {
lo = TCGV128_LOW(val);
hi = TCGV128_HIGH(val);
}
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_ld_a32_i128;
} else {
opc = INDEX_op_qemu_ld_a64_i128;
}
gen_ldst(opc, tcgv_i64_temp(lo), tcgv_i64_temp(hi), addr, oi);
if (need_bswap) {
tcg_gen_bswap64_i64(lo, lo);
tcg_gen_bswap64_i64(hi, hi);
}
} else if (use_two_i64_for_i128(memop)) {
MemOp mop[2];
TCGTemp *addr_p8;
TCGv_i64 x, y;
bool need_bswap;
canonicalize_memop_i128_as_i64(mop, memop);
need_bswap = (mop[0] ^ memop) & MO_BSWAP;
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_ld_a32_i64;
} else {
opc = INDEX_op_qemu_ld_a64_i64;
}
/*
* Since there are no global TCGv_i128, there is no visible state
* changed if the second load faults. Load directly into the two
* subwords.
*/
if ((memop & MO_BSWAP) == MO_LE) {
x = TCGV128_LOW(val);
y = TCGV128_HIGH(val);
} else {
x = TCGV128_HIGH(val); y = TCGV128_LOW(val);
}
gen_ldst_i64(opc, x, addr, make_memop_idx(mop[0], idx));
if (need_bswap) {
tcg_gen_bswap64_i64(x, x);
}
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
TCGv_i32 t = tcg_temp_ebb_new_i32();
tcg_gen_addi_i32(t, temp_tcgv_i32(addr), 8);
addr_p8 = tcgv_i32_temp(t);
} else {
TCGv_i64 t = tcg_temp_ebb_new_i64();
tcg_gen_addi_i64(t, temp_tcgv_i64(addr), 8);
addr_p8 = tcgv_i64_temp(t);
}
gen_ldst_i64(opc, y, addr_p8, make_memop_idx(mop[1], idx));
tcg_temp_free_internal(addr_p8);
if (need_bswap) {
tcg_gen_bswap64_i64(y, y);
}
} else {
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
ext_addr = tcg_temp_ebb_new_i64();
tcg_gen_extu_i32_i64(ext_addr, temp_tcgv_i32(addr));
addr = tcgv_i64_temp(ext_addr);
}
gen_helper_ld_i128(val, cpu_env, temp_tcgv_i64(addr),
tcg_constant_i32(orig_oi));
}
plugin_gen_mem_callbacks(ext_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
}
void tcg_gen_qemu_ld_i128_chk(TCGv_i128 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) == MO_128);
tcg_debug_assert((memop & MO_SIGN) == 0);
tcg_gen_qemu_ld_i128_int(val, addr, idx, memop);
}
static void tcg_gen_qemu_st_i128_int(TCGv_i128 val, TCGTemp *addr,
TCGArg idx, MemOp memop)
{
const MemOpIdx orig_oi = make_memop_idx(memop, idx);
TCGv_i64 ext_addr = NULL;
TCGOpcode opc;
check_max_alignment(get_alignment_bits(memop));
tcg_gen_req_mo(TCG_MO_ST_LD | TCG_MO_ST_ST);
/* TODO: For now, force 32-bit hosts to use the helper. */
if (TCG_TARGET_HAS_qemu_ldst_i128 && TCG_TARGET_REG_BITS == 64) {
TCGv_i64 lo, hi;
MemOpIdx oi = orig_oi;
bool need_bswap = false;
if ((memop & MO_BSWAP) && !tcg_target_has_memory_bswap(memop)) {
lo = tcg_temp_ebb_new_i64();
hi = tcg_temp_ebb_new_i64();
tcg_gen_bswap64_i64(lo, TCGV128_HIGH(val));
tcg_gen_bswap64_i64(hi, TCGV128_LOW(val));
oi = make_memop_idx(memop & ~MO_BSWAP, idx); need_bswap = true;
} else {
lo = TCGV128_LOW(val);
hi = TCGV128_HIGH(val);
}
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_st_a32_i128;
} else {
opc = INDEX_op_qemu_st_a64_i128;
}
gen_ldst(opc, tcgv_i64_temp(lo), tcgv_i64_temp(hi), addr, oi);
if (need_bswap) {
tcg_temp_free_i64(lo);
tcg_temp_free_i64(hi);
}
} else if (use_two_i64_for_i128(memop)) {
MemOp mop[2];
TCGTemp *addr_p8;
TCGv_i64 x, y, b = NULL;
canonicalize_memop_i128_as_i64(mop, memop);
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
opc = INDEX_op_qemu_st_a32_i64;
} else {
opc = INDEX_op_qemu_st_a64_i64;
}
if ((memop & MO_BSWAP) == MO_LE) {
x = TCGV128_LOW(val);
y = TCGV128_HIGH(val);
} else {
x = TCGV128_HIGH(val);
y = TCGV128_LOW(val);
}
if ((mop[0] ^ memop) & MO_BSWAP) {
b = tcg_temp_ebb_new_i64();
tcg_gen_bswap64_i64(b, x);
x = b;
}
gen_ldst_i64(opc, x, addr, make_memop_idx(mop[0], idx));
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
TCGv_i32 t = tcg_temp_ebb_new_i32();
tcg_gen_addi_i32(t, temp_tcgv_i32(addr), 8);
addr_p8 = tcgv_i32_temp(t);
} else {
TCGv_i64 t = tcg_temp_ebb_new_i64();
tcg_gen_addi_i64(t, temp_tcgv_i64(addr), 8);
addr_p8 = tcgv_i64_temp(t);
}
if (b) {
tcg_gen_bswap64_i64(b, y);
gen_ldst_i64(opc, b, addr_p8, make_memop_idx(mop[1], idx));
tcg_temp_free_i64(b);
} else {
gen_ldst_i64(opc, y, addr_p8, make_memop_idx(mop[1], idx));
}
tcg_temp_free_internal(addr_p8);
} else {
if (tcg_ctx->addr_type == TCG_TYPE_I32) {
ext_addr = tcg_temp_ebb_new_i64();
tcg_gen_extu_i32_i64(ext_addr, temp_tcgv_i32(addr));
addr = tcgv_i64_temp(ext_addr);
} gen_helper_st_i128(cpu_env, temp_tcgv_i64(addr), val,
tcg_constant_i32(orig_oi));
}
plugin_gen_mem_callbacks(ext_addr, addr, orig_oi, QEMU_PLUGIN_MEM_W);
}
void tcg_gen_qemu_st_i128_chk(TCGv_i128 val, TCGTemp *addr, TCGArg idx,
MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) == MO_128);
tcg_debug_assert((memop & MO_SIGN) == 0);
tcg_gen_qemu_st_i128_int(val, addr, idx, memop);
}
static void tcg_gen_ext_i32(TCGv_i32 ret, TCGv_i32 val, MemOp opc)
{
switch (opc & MO_SSIZE) {
case MO_SB:
tcg_gen_ext8s_i32(ret, val);
break;
case MO_UB:
tcg_gen_ext8u_i32(ret, val);
break;
case MO_SW:
tcg_gen_ext16s_i32(ret, val);
break;
case MO_UW:
tcg_gen_ext16u_i32(ret, val);
break;
default:
tcg_gen_mov_i32(ret, val);
break;
}
}
static void tcg_gen_ext_i64(TCGv_i64 ret, TCGv_i64 val, MemOp opc)
{
switch (opc & MO_SSIZE) {
case MO_SB:
tcg_gen_ext8s_i64(ret, val);
break;
case MO_UB:
tcg_gen_ext8u_i64(ret, val);
break;
case MO_SW:
tcg_gen_ext16s_i64(ret, val);
break;
case MO_UW:
tcg_gen_ext16u_i64(ret, val);
break;
case MO_SL:
tcg_gen_ext32s_i64(ret, val);
break;
case MO_UL:
tcg_gen_ext32u_i64(ret, val);
break;
default:
tcg_gen_mov_i64(ret, val);
break;
}
}
typedef void (*gen_atomic_cx_i32)(TCGv_i32, TCGv_env, TCGv_i64,
TCGv_i32, TCGv_i32, TCGv_i32);
typedef void (*gen_atomic_cx_i64)(TCGv_i64, TCGv_env, TCGv_i64,
TCGv_i64, TCGv_i64, TCGv_i32);
typedef void (*gen_atomic_cx_i128)(TCGv_i128, TCGv_env, TCGv_i64,
TCGv_i128, TCGv_i128, TCGv_i32);typedef void (*gen_atomic_op_i32)(TCGv_i32, TCGv_env, TCGv_i64,
TCGv_i32, TCGv_i32);
typedef void (*gen_atomic_op_i64)(TCGv_i64, TCGv_env, TCGv_i64,
TCGv_i64, TCGv_i32);
#ifdef CONFIG_ATOMIC64
# define WITH_ATOMIC64(X) X,
#else
# define WITH_ATOMIC64(X)
#endif
#ifdef CONFIG_CMPXCHG128
# define WITH_ATOMIC128(X) X,
#else
# define WITH_ATOMIC128(X)
#endif
static void * const table_cmpxchg[(MO_SIZE | MO_BSWAP) + 1] = {
[MO_8] = gen_helper_atomic_cmpxchgb,
[MO_16 | MO_LE] = gen_helper_atomic_cmpxchgw_le,
[MO_16 | MO_BE] = gen_helper_atomic_cmpxchgw_be,
[MO_32 | MO_LE] = gen_helper_atomic_cmpxchgl_le,
[MO_32 | MO_BE] = gen_helper_atomic_cmpxchgl_be,
WITH_ATOMIC64([MO_64 | MO_LE] = gen_helper_atomic_cmpxchgq_le)
WITH_ATOMIC64([MO_64 | MO_BE] = gen_helper_atomic_cmpxchgq_be)
WITH_ATOMIC128([MO_128 | MO_LE] = gen_helper_atomic_cmpxchgo_le)
WITH_ATOMIC128([MO_128 | MO_BE] = gen_helper_atomic_cmpxchgo_be)
};
static void tcg_gen_nonatomic_cmpxchg_i32_int(TCGv_i32 retv, TCGTemp *addr,
TCGv_i32 cmpv, TCGv_i32 newv,
TCGArg idx, MemOp memop)
{
TCGv_i32 t1 = tcg_temp_ebb_new_i32();
TCGv_i32 t2 = tcg_temp_ebb_new_i32();
tcg_gen_ext_i32(t2, cmpv, memop & MO_SIZE);
tcg_gen_qemu_ld_i32_int(t1, addr, idx, memop & ~MO_SIGN);
tcg_gen_movcond_i32(TCG_COND_EQ, t2, t1, t2, newv, t1);
tcg_gen_qemu_st_i32_int(t2, addr, idx, memop);
tcg_temp_free_i32(t2);
if (memop & MO_SIGN) {
tcg_gen_ext_i32(retv, t1, memop);
} else {
tcg_gen_mov_i32(retv, t1);
}
tcg_temp_free_i32(t1);
}
void tcg_gen_nonatomic_cmpxchg_i32_chk(TCGv_i32 retv, TCGTemp *addr,
TCGv_i32 cmpv, TCGv_i32 newv,
TCGArg idx, MemOp memop,
TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_32);
tcg_gen_nonatomic_cmpxchg_i32_int(retv, addr, cmpv, newv, idx, memop);
}
static void tcg_gen_atomic_cmpxchg_i32_int(TCGv_i32 retv, TCGTemp *addr,
TCGv_i32 cmpv, TCGv_i32 newv,
TCGArg idx, MemOp memop)
{
gen_atomic_cx_i32 gen;
TCGv_i64 a64;
MemOpIdx oi;
if (!(tcg_ctx->gen_tb->cflags & CF_PARALLEL)) {
tcg_gen_nonatomic_cmpxchg_i32_int(retv, addr, cmpv, newv, idx, memop); return;
}
memop = tcg_canonicalize_memop(memop, 0, 0);
gen = table_cmpxchg[memop & (MO_SIZE | MO_BSWAP)];
tcg_debug_assert(gen != NULL);
oi = make_memop_idx(memop & ~MO_SIGN, idx);
a64 = maybe_extend_addr64(addr);
gen(retv, cpu_env, a64, cmpv, newv, tcg_constant_i32(oi));
maybe_free_addr64(a64);
if (memop & MO_SIGN) {
tcg_gen_ext_i32(retv, retv, memop);
}
}
void tcg_gen_atomic_cmpxchg_i32_chk(TCGv_i32 retv, TCGTemp *addr,
TCGv_i32 cmpv, TCGv_i32 newv,
TCGArg idx, MemOp memop,
TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_32);
tcg_gen_atomic_cmpxchg_i32_int(retv, addr, cmpv, newv, idx, memop);
}
static void tcg_gen_nonatomic_cmpxchg_i64_int(TCGv_i64 retv, TCGTemp *addr,
TCGv_i64 cmpv, TCGv_i64 newv,
TCGArg idx, MemOp memop)
{
TCGv_i64 t1, t2;
if (TCG_TARGET_REG_BITS == 32 && (memop & MO_SIZE) < MO_64) {
tcg_gen_nonatomic_cmpxchg_i32_int(TCGV_LOW(retv), addr, TCGV_LOW(cmpv),
TCGV_LOW(newv), idx, memop);
if (memop & MO_SIGN) {
tcg_gen_sari_i32(TCGV_HIGH(retv), TCGV_LOW(retv), 31);
} else {
tcg_gen_movi_i32(TCGV_HIGH(retv), 0);
}
return;
}
t1 = tcg_temp_ebb_new_i64();
t2 = tcg_temp_ebb_new_i64();
tcg_gen_ext_i64(t2, cmpv, memop & MO_SIZE);
tcg_gen_qemu_ld_i64_int(t1, addr, idx, memop & ~MO_SIGN);
tcg_gen_movcond_i64(TCG_COND_EQ, t2, t1, t2, newv, t1);
tcg_gen_qemu_st_i64_int(t2, addr, idx, memop);
tcg_temp_free_i64(t2);
if (memop & MO_SIGN) {
tcg_gen_ext_i64(retv, t1, memop);
} else {
tcg_gen_mov_i64(retv, t1);
}
tcg_temp_free_i64(t1);
}
void tcg_gen_nonatomic_cmpxchg_i64_chk(TCGv_i64 retv, TCGTemp *addr,
TCGv_i64 cmpv, TCGv_i64 newv,
TCGArg idx, MemOp memop,
TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_64);
tcg_gen_nonatomic_cmpxchg_i64_int(retv, addr, cmpv, newv, idx, memop);}
static void tcg_gen_atomic_cmpxchg_i64_int(TCGv_i64 retv, TCGTemp *addr,
TCGv_i64 cmpv, TCGv_i64 newv,
TCGArg idx, MemOp memop)
{
if (!(tcg_ctx->gen_tb->cflags & CF_PARALLEL)) {
tcg_gen_nonatomic_cmpxchg_i64_int(retv, addr, cmpv, newv, idx, memop);
return;
}
if ((memop & MO_SIZE) == MO_64) {
gen_atomic_cx_i64 gen;
memop = tcg_canonicalize_memop(memop, 1, 0);
gen = table_cmpxchg[memop & (MO_SIZE | MO_BSWAP)];
if (gen) {
MemOpIdx oi = make_memop_idx(memop, idx);
TCGv_i64 a64 = maybe_extend_addr64(addr);
gen(retv, cpu_env, a64, cmpv, newv, tcg_constant_i32(oi));
maybe_free_addr64(a64);
return;
}
gen_helper_exit_atomic(cpu_env);
/*
* Produce a result for a well-formed opcode stream. This satisfies
* liveness for set before used, which happens before this dead code
* is removed.
*/
tcg_gen_movi_i64(retv, 0);
return;
}
if (TCG_TARGET_REG_BITS == 32) {
tcg_gen_atomic_cmpxchg_i32_int(TCGV_LOW(retv), addr, TCGV_LOW(cmpv),
TCGV_LOW(newv), idx, memop);
if (memop & MO_SIGN) {
tcg_gen_sari_i32(TCGV_HIGH(retv), TCGV_LOW(retv), 31);
} else {
tcg_gen_movi_i32(TCGV_HIGH(retv), 0);
}
} else {
TCGv_i32 c32 = tcg_temp_ebb_new_i32();
TCGv_i32 n32 = tcg_temp_ebb_new_i32();
TCGv_i32 r32 = tcg_temp_ebb_new_i32();
tcg_gen_extrl_i64_i32(c32, cmpv);
tcg_gen_extrl_i64_i32(n32, newv);
tcg_gen_atomic_cmpxchg_i32_int(r32, addr, c32, n32,
idx, memop & ~MO_SIGN);
tcg_temp_free_i32(c32);
tcg_temp_free_i32(n32);
tcg_gen_extu_i32_i64(retv, r32);
tcg_temp_free_i32(r32);
if (memop & MO_SIGN) {
tcg_gen_ext_i64(retv, retv, memop);
}
}
}
void tcg_gen_atomic_cmpxchg_i64_chk(TCGv_i64 retv, TCGTemp *addr,
TCGv_i64 cmpv, TCGv_i64 newv,
TCGArg idx, MemOp memop, TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & MO_SIZE) <= MO_64); tcg_gen_atomic_cmpxchg_i64_int(retv, addr, cmpv, newv, idx, memop);
}
static void tcg_gen_nonatomic_cmpxchg_i128_int(TCGv_i128 retv, TCGTemp *addr,
TCGv_i128 cmpv, TCGv_i128 newv,
TCGArg idx, MemOp memop)
{
if (TCG_TARGET_REG_BITS == 32) {
/* Inline expansion below is simply too large for 32-bit hosts. */
MemOpIdx oi = make_memop_idx(memop, idx);
TCGv_i64 a64 = maybe_extend_addr64(addr);
gen_helper_nonatomic_cmpxchgo(retv, cpu_env, a64, cmpv, newv,
tcg_constant_i32(oi));
maybe_free_addr64(a64);
} else {
TCGv_i128 oldv = tcg_temp_ebb_new_i128();
TCGv_i128 tmpv = tcg_temp_ebb_new_i128();
TCGv_i64 t0 = tcg_temp_ebb_new_i64();
TCGv_i64 t1 = tcg_temp_ebb_new_i64();
TCGv_i64 z = tcg_constant_i64(0);
tcg_gen_qemu_ld_i128_int(oldv, addr, idx, memop);
/* Compare i128 */
tcg_gen_xor_i64(t0, TCGV128_LOW(oldv), TCGV128_LOW(cmpv));
tcg_gen_xor_i64(t1, TCGV128_HIGH(oldv), TCGV128_HIGH(cmpv));
tcg_gen_or_i64(t0, t0, t1);
/* tmpv = equal ? newv : oldv */
tcg_gen_movcond_i64(TCG_COND_EQ, TCGV128_LOW(tmpv), t0, z,
TCGV128_LOW(newv), TCGV128_LOW(oldv));
tcg_gen_movcond_i64(TCG_COND_EQ, TCGV128_HIGH(tmpv), t0, z,
TCGV128_HIGH(newv), TCGV128_HIGH(oldv));
/* Unconditional writeback. */
tcg_gen_qemu_st_i128_int(tmpv, addr, idx, memop);
tcg_gen_mov_i128(retv, oldv);
tcg_temp_free_i64(t0);
tcg_temp_free_i64(t1);
tcg_temp_free_i128(tmpv);
tcg_temp_free_i128(oldv);
}
}
void tcg_gen_nonatomic_cmpxchg_i128_chk(TCGv_i128 retv, TCGTemp *addr,
TCGv_i128 cmpv, TCGv_i128 newv,
TCGArg idx, MemOp memop,
TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & (MO_SIZE | MO_SIGN)) == MO_128);
tcg_gen_nonatomic_cmpxchg_i128_int(retv, addr, cmpv, newv, idx, memop);
}
static void tcg_gen_atomic_cmpxchg_i128_int(TCGv_i128 retv, TCGTemp *addr,
TCGv_i128 cmpv, TCGv_i128 newv,
TCGArg idx, MemOp memop)
{
gen_atomic_cx_i128 gen;
if (!(tcg_ctx->gen_tb->cflags & CF_PARALLEL)) {
tcg_gen_nonatomic_cmpxchg_i128_int(retv, addr, cmpv, newv, idx, memop);
return;
}
gen = table_cmpxchg[memop & (MO_SIZE | MO_BSWAP)];
if (gen) {
MemOpIdx oi = make_memop_idx(memop, idx); TCGv_i64 a64 = maybe_extend_addr64(addr);
gen(retv, cpu_env, a64, cmpv, newv, tcg_constant_i32(oi));
maybe_free_addr64(a64);
return;
}
gen_helper_exit_atomic(cpu_env);
/*
* Produce a result for a well-formed opcode stream. This satisfies
* liveness for set before used, which happens before this dead code
* is removed.
*/
tcg_gen_movi_i64(TCGV128_LOW(retv), 0);
tcg_gen_movi_i64(TCGV128_HIGH(retv), 0);
}
void tcg_gen_atomic_cmpxchg_i128_chk(TCGv_i128 retv, TCGTemp *addr,
TCGv_i128 cmpv, TCGv_i128 newv,
TCGArg idx, MemOp memop,
TCGType addr_type)
{
tcg_debug_assert(addr_type == tcg_ctx->addr_type);
tcg_debug_assert((memop & (MO_SIZE | MO_SIGN)) == MO_128);
tcg_gen_atomic_cmpxchg_i128_int(retv, addr, cmpv, newv, idx, memop);
}
static void do_nonatomic_op_i32(TCGv_i32 ret, TCGTemp *addr, TCGv_i32 val,
TCGArg idx, MemOp memop, bool new_val,
void (*gen)(TCGv_i32, TCGv_i32, TCGv_i32))
{
TCGv_i32 t1 = tcg_temp_ebb_new_i32();
TCGv_i32 t2 = tcg_temp_ebb_new_i32();
memop = tcg_canonicalize_memop(memop, 0, 0);
tcg_gen_qemu_ld_i32_int(t1, addr, idx, memop);
tcg_gen_ext_i32(t2, val, memop);
gen(t2, t1, t2);
tcg_gen_qemu_st_i32_int(t2, addr, idx, memop);
tcg_gen_ext_i32(ret, (new_val ? t2 : t1), memop);
tcg_temp_free_i32(t1);
tcg_temp_free_i32(t2);
}
static void do_atomic_op_i32(TCGv_i32 ret, TCGTemp *addr, TCGv_i32 val,
TCGArg idx, MemOp memop, void * const table[])
{
gen_atomic_op_i32 gen;
TCGv_i64 a64;
MemOpIdx oi;
memop = tcg_canonicalize_memop(memop, 0, 0);
gen = table[memop & (MO_SIZE | MO_BSWAP)];
tcg_debug_assert(gen != NULL);
oi = make_memop_idx(memop & ~MO_SIGN, idx);
a64 = maybe_extend_addr64(addr);
gen(ret, cpu_env, a64, val, tcg_constant_i32(oi));
maybe_free_addr64(a64);
if (memop & MO_SIGN) {
tcg_gen_ext_i32(ret, ret, memop);
}
}
static void do_nonatomic_op_i64(TCGv_i64 ret, TCGTemp *addr, TCGv_i64 val,
TCGArg idx, MemOp memop, bool new_val, void (*gen)(TCGv_i64, TCGv_i64, TCGv_i64))
{
TCGv_i64 t1 = tcg_temp_ebb_new_i64();
TCGv_i64 t2 = tcg_temp_ebb_new_i64();
memop = tcg_canonicalize_memop(memop, 1, 0);
tcg_gen_qemu_ld_i64_int(t1, addr, idx, memop);
tcg_gen_ext_i64(t2, val, memop);
gen(t2, t1, t2);
tcg_gen_qemu_st_i64_int(t2, addr, idx, memop);
tcg_gen_ext_i64(ret, (new_val ? t2 : t1), memop);
tcg_temp_free_i64(t1);
tcg_temp_free_i64(t2);
}
static void do_atomic_op_i64(TCGv_i64 ret, TCGTemp *addr, TCGv_i64 val,
TCGArg idx, MemOp memop, void * const table[])
{
memop = tcg_canonicalize_memop(memop, 1, 0);
if ((memop & MO_SIZE) == MO_64) {
gen_atomic_op_i64 gen = table[memop & (MO_SIZE | MO_BSWAP)];
if (gen) {
MemOpIdx oi = make_memop_idx(memop & ~MO_SIGN, idx);
TCGv_i64 a64 = maybe_extend_addr64(addr);
gen(ret, cpu_env, a64, val, tcg_constant_i32(oi));
maybe_free_addr64(a64);
return;
}
gen_helper_exit_atomic(cpu_env);
/* Produce a result, so that we have a well-formed opcode stream
with respect to uses of the result in the (dead) code following. */
tcg_gen_movi_i64(ret, 0);
} else {
TCGv_i32 v32 = tcg_temp_ebb_new_i32();
TCGv_i32 r32 = tcg_temp_ebb_new_i32();
tcg_gen_extrl_i64_i32(v32, val);
do_atomic_op_i32(r32, addr, v32, idx, memop & ~MO_SIGN, table);
tcg_temp_free_i32(v32);
tcg_gen_extu_i32_i64(ret, r32);
tcg_temp_free_i32(r32);
if (memop & MO_SIGN) {
tcg_gen_ext_i64(ret, ret, memop);
}
}
}
#define GEN_ATOMIC_HELPER(NAME, OP, NEW) \
static void * const table_##NAME[(MO_SIZE | MO_BSWAP) + 1] = { \
[MO_8] = gen_helper_atomic_##NAME##b, \
[MO_16 | MO_LE] = gen_helper_atomic_##NAME##w_le, \
[MO_16 | MO_BE] = gen_helper_atomic_##NAME##w_be, \
[MO_32 | MO_LE] = gen_helper_atomic_##NAME##l_le, \
[MO_32 | MO_BE] = gen_helper_atomic_##NAME##l_be, \
WITH_ATOMIC64([MO_64 | MO_LE] = gen_helper_atomic_##NAME##q_le) \
WITH_ATOMIC64([MO_64 | MO_BE] = gen_helper_atomic_##NAME##q_be) \
}; \
void tcg_gen_atomic_##NAME##_i32_chk(TCGv_i32 ret, TCGTemp *addr, \
TCGv_i32 val, TCGArg idx, \
MemOp memop, TCGType addr_type) \
{ \
tcg_debug_assert(addr_type == tcg_ctx->addr_type); \
tcg_debug_assert((memop & MO_SIZE) <= MO_32); \ if (tcg_ctx->gen_tb->cflags & CF_PARALLEL) { \
do_atomic_op_i32(ret, addr, val, idx, memop, table_##NAME); \
} else { \
do_nonatomic_op_i32(ret, addr, val, idx, memop, NEW, \
tcg_gen_##OP##_i32); \
} \
} \
void tcg_gen_atomic_##NAME##_i64_chk(TCGv_i64 ret, TCGTemp *addr, \
TCGv_i64 val, TCGArg idx, \
MemOp memop, TCGType addr_type) \
{ \
tcg_debug_assert(addr_type == tcg_ctx->addr_type); \
tcg_debug_assert((memop & MO_SIZE) <= MO_64); \
if (tcg_ctx->gen_tb->cflags & CF_PARALLEL) { \
do_atomic_op_i64(ret, addr, val, idx, memop, table_##NAME); \
} else { \
do_nonatomic_op_i64(ret, addr, val, idx, memop, NEW, \
tcg_gen_##OP##_i64); \
} \
}
GEN_ATOMIC_HELPER(fetch_add, add, 0)
GEN_ATOMIC_HELPER(fetch_and, and, 0)
GEN_ATOMIC_HELPER(fetch_or, or, 0)
GEN_ATOMIC_HELPER(fetch_xor, xor, 0)
GEN_ATOMIC_HELPER(fetch_smin, smin, 0)
GEN_ATOMIC_HELPER(fetch_umin, umin, 0)
GEN_ATOMIC_HELPER(fetch_smax, smax, 0)
GEN_ATOMIC_HELPER(fetch_umax, umax, 0)
GEN_ATOMIC_HELPER(add_fetch, add, 1)
GEN_ATOMIC_HELPER(and_fetch, and, 1)
GEN_ATOMIC_HELPER(or_fetch, or, 1)
GEN_ATOMIC_HELPER(xor_fetch, xor, 1)
GEN_ATOMIC_HELPER(smin_fetch, smin, 1)
GEN_ATOMIC_HELPER(umin_fetch, umin, 1)
GEN_ATOMIC_HELPER(smax_fetch, smax, 1)
GEN_ATOMIC_HELPER(umax_fetch, umax, 1)
static void tcg_gen_mov2_i32(TCGv_i32 r, TCGv_i32 a, TCGv_i32 b)
{
tcg_gen_mov_i32(r, b);
}
static void tcg_gen_mov2_i64(TCGv_i64 r, TCGv_i64 a, TCGv_i64 b)
{
tcg_gen_mov_i64(r, b);
}
GEN_ATOMIC_HELPER(xchg, mov2, 0)
#undef GEN_ATOMIC_HELPER