qemu-e2k/tcg/loongarch64/tcg-target.c.inc
WANG Xuerui e3b15766b9 tcg/loongarch64: Implement goto_ptr
Signed-off-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211221054105.178795-11-git@xen0n.name>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-12-21 13:17:06 -08:00

421 lines
11 KiB
C++

/*
* Tiny Code Generator for QEMU
*
* Copyright (c) 2021 WANG Xuerui <git@xen0n.name>
*
* Based on tcg/riscv/tcg-target.c.inc
*
* Copyright (c) 2018 SiFive, Inc
* Copyright (c) 2008-2009 Arnaud Patard <arnaud.patard@rtp-net.org>
* Copyright (c) 2009 Aurelien Jarno <aurelien@aurel32.net>
* 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.
*/
#ifdef CONFIG_DEBUG_TCG
static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
"zero",
"ra",
"tp",
"sp",
"a0",
"a1",
"a2",
"a3",
"a4",
"a5",
"a6",
"a7",
"t0",
"t1",
"t2",
"t3",
"t4",
"t5",
"t6",
"t7",
"t8",
"r21", /* reserved in the LP64* ABI, hence no ABI name */
"s9",
"s0",
"s1",
"s2",
"s3",
"s4",
"s5",
"s6",
"s7",
"s8"
};
#endif
static const int tcg_target_reg_alloc_order[] = {
/* Registers preserved across calls */
/* TCG_REG_S0 reserved for TCG_AREG0 */
TCG_REG_S1,
TCG_REG_S2,
TCG_REG_S3,
TCG_REG_S4,
TCG_REG_S5,
TCG_REG_S6,
TCG_REG_S7,
TCG_REG_S8,
TCG_REG_S9,
/* Registers (potentially) clobbered across calls */
TCG_REG_T0,
TCG_REG_T1,
TCG_REG_T2,
TCG_REG_T3,
TCG_REG_T4,
TCG_REG_T5,
TCG_REG_T6,
TCG_REG_T7,
TCG_REG_T8,
/* Argument registers, opposite order of allocation. */
TCG_REG_A7,
TCG_REG_A6,
TCG_REG_A5,
TCG_REG_A4,
TCG_REG_A3,
TCG_REG_A2,
TCG_REG_A1,
TCG_REG_A0,
};
static const int tcg_target_call_iarg_regs[] = {
TCG_REG_A0,
TCG_REG_A1,
TCG_REG_A2,
TCG_REG_A3,
TCG_REG_A4,
TCG_REG_A5,
TCG_REG_A6,
TCG_REG_A7,
};
static const int tcg_target_call_oarg_regs[] = {
TCG_REG_A0,
TCG_REG_A1,
};
#define TCG_CT_CONST_ZERO 0x100
#define TCG_CT_CONST_S12 0x200
#define TCG_CT_CONST_N12 0x400
#define TCG_CT_CONST_U12 0x800
#define TCG_CT_CONST_C12 0x1000
#define TCG_CT_CONST_WSZ 0x2000
#define ALL_GENERAL_REGS MAKE_64BIT_MASK(0, 32)
/*
* For softmmu, we need to avoid conflicts with the first 5
* argument registers to call the helper. Some of these are
* also used for the tlb lookup.
*/
#ifdef CONFIG_SOFTMMU
#define SOFTMMU_RESERVE_REGS MAKE_64BIT_MASK(TCG_REG_A0, 5)
#else
#define SOFTMMU_RESERVE_REGS 0
#endif
static inline tcg_target_long sextreg(tcg_target_long val, int pos, int len)
{
return sextract64(val, pos, len);
}
/* test if a constant matches the constraint */
static bool tcg_target_const_match(int64_t val, TCGType type, int ct)
{
if (ct & TCG_CT_CONST) {
return true;
}
if ((ct & TCG_CT_CONST_ZERO) && val == 0) {
return true;
}
if ((ct & TCG_CT_CONST_S12) && val == sextreg(val, 0, 12)) {
return true;
}
if ((ct & TCG_CT_CONST_N12) && -val == sextreg(-val, 0, 12)) {
return true;
}
if ((ct & TCG_CT_CONST_U12) && val >= 0 && val <= 0xfff) {
return true;
}
if ((ct & TCG_CT_CONST_C12) && ~val >= 0 && ~val <= 0xfff) {
return true;
}
if ((ct & TCG_CT_CONST_WSZ) && val == (type == TCG_TYPE_I32 ? 32 : 64)) {
return true;
}
return false;
}
/*
* Relocations
*/
/*
* Relocation records defined in LoongArch ELF psABI v1.00 is way too
* complicated; a whopping stack machine is needed to stuff the fields, at
* the very least one SOP_PUSH and one SOP_POP (of the correct format) are
* needed.
*
* Hence, define our own simpler relocation types. Numbers are chosen as to
* not collide with potential future additions to the true ELF relocation
* type enum.
*/
/* Field Sk16, shifted right by 2; suitable for conditional jumps */
#define R_LOONGARCH_BR_SK16 256
/* Field Sd10k16, shifted right by 2; suitable for B and BL */
#define R_LOONGARCH_BR_SD10K16 257
static bool reloc_br_sk16(tcg_insn_unit *src_rw, const tcg_insn_unit *target)
{
const tcg_insn_unit *src_rx = tcg_splitwx_to_rx(src_rw);
intptr_t offset = (intptr_t)target - (intptr_t)src_rx;
tcg_debug_assert((offset & 3) == 0);
offset >>= 2;
if (offset == sextreg(offset, 0, 16)) {
*src_rw = deposit64(*src_rw, 10, 16, offset);
return true;
}
return false;
}
static bool reloc_br_sd10k16(tcg_insn_unit *src_rw,
const tcg_insn_unit *target)
{
const tcg_insn_unit *src_rx = tcg_splitwx_to_rx(src_rw);
intptr_t offset = (intptr_t)target - (intptr_t)src_rx;
tcg_debug_assert((offset & 3) == 0);
offset >>= 2;
if (offset == sextreg(offset, 0, 26)) {
*src_rw = deposit64(*src_rw, 0, 10, offset >> 16); /* slot d10 */
*src_rw = deposit64(*src_rw, 10, 16, offset); /* slot k16 */
return true;
}
return false;
}
static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
intptr_t value, intptr_t addend)
{
tcg_debug_assert(addend == 0);
switch (type) {
case R_LOONGARCH_BR_SK16:
return reloc_br_sk16(code_ptr, (tcg_insn_unit *)value);
case R_LOONGARCH_BR_SD10K16:
return reloc_br_sd10k16(code_ptr, (tcg_insn_unit *)value);
default:
g_assert_not_reached();
}
}
#include "tcg-insn-defs.c.inc"
/*
* TCG intrinsics
*/
static void tcg_out_mb(TCGContext *s, TCGArg a0)
{
/* Baseline LoongArch only has the full barrier, unfortunately. */
tcg_out_opc_dbar(s, 0);
}
static bool tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg)
{
if (ret == arg) {
return true;
}
switch (type) {
case TCG_TYPE_I32:
case TCG_TYPE_I64:
/*
* Conventional register-register move used in LoongArch is
* `or dst, src, zero`.
*/
tcg_out_opc_or(s, ret, arg, TCG_REG_ZERO);
break;
default:
g_assert_not_reached();
}
return true;
}
static bool imm_part_needs_loading(bool high_bits_are_ones,
tcg_target_long part)
{
if (high_bits_are_ones) {
return part != -1;
} else {
return part != 0;
}
}
/* Loads a 32-bit immediate into rd, sign-extended. */
static void tcg_out_movi_i32(TCGContext *s, TCGReg rd, int32_t val)
{
tcg_target_long lo = sextreg(val, 0, 12);
tcg_target_long hi12 = sextreg(val, 12, 20);
/* Single-instruction cases. */
if (lo == val) {
/* val fits in simm12: addi.w rd, zero, val */
tcg_out_opc_addi_w(s, rd, TCG_REG_ZERO, val);
return;
}
if (0x800 <= val && val <= 0xfff) {
/* val fits in uimm12: ori rd, zero, val */
tcg_out_opc_ori(s, rd, TCG_REG_ZERO, val);
return;
}
/* High bits must be set; load with lu12i.w + optional ori. */
tcg_out_opc_lu12i_w(s, rd, hi12);
if (lo != 0) {
tcg_out_opc_ori(s, rd, rd, lo & 0xfff);
}
}
static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
tcg_target_long val)
{
/*
* LoongArch conventionally loads 64-bit immediates in at most 4 steps,
* with dedicated instructions for filling the respective bitfields
* below:
*
* 6 5 4 3
* 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2
* +-----------------------+---------------------------------------+...
* | hi52 | hi32 |
* +-----------------------+---------------------------------------+...
* 3 2 1
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
* ...+-------------------------------------+-------------------------+
* | hi12 | lo |
* ...+-------------------------------------+-------------------------+
*
* Check if val belong to one of the several fast cases, before falling
* back to the slow path.
*/
intptr_t pc_offset;
tcg_target_long val_lo, val_hi, pc_hi, offset_hi;
tcg_target_long hi32, hi52;
bool rd_high_bits_are_ones;
/* Value fits in signed i32. */
if (type == TCG_TYPE_I32 || val == (int32_t)val) {
tcg_out_movi_i32(s, rd, val);
return;
}
/* PC-relative cases. */
pc_offset = tcg_pcrel_diff(s, (void *)val);
if (pc_offset == sextreg(pc_offset, 0, 22) && (pc_offset & 3) == 0) {
/* Single pcaddu2i. */
tcg_out_opc_pcaddu2i(s, rd, pc_offset >> 2);
return;
}
if (pc_offset == (int32_t)pc_offset) {
/* Offset within 32 bits; load with pcalau12i + ori. */
val_lo = sextreg(val, 0, 12);
val_hi = val >> 12;
pc_hi = (val - pc_offset) >> 12;
offset_hi = val_hi - pc_hi;
tcg_debug_assert(offset_hi == sextreg(offset_hi, 0, 20));
tcg_out_opc_pcalau12i(s, rd, offset_hi);
if (val_lo != 0) {
tcg_out_opc_ori(s, rd, rd, val_lo & 0xfff);
}
return;
}
hi32 = sextreg(val, 32, 20);
hi52 = sextreg(val, 52, 12);
/* Single cu52i.d case. */
if (ctz64(val) >= 52) {
tcg_out_opc_cu52i_d(s, rd, TCG_REG_ZERO, hi52);
return;
}
/* Slow path. Initialize the low 32 bits, then concat high bits. */
tcg_out_movi_i32(s, rd, val);
rd_high_bits_are_ones = (int32_t)val < 0;
if (imm_part_needs_loading(rd_high_bits_are_ones, hi32)) {
tcg_out_opc_cu32i_d(s, rd, hi32);
rd_high_bits_are_ones = hi32 < 0;
}
if (imm_part_needs_loading(rd_high_bits_are_ones, hi52)) {
tcg_out_opc_cu52i_d(s, rd, rd, hi52);
}
}
/*
* Entry-points
*/
static void tcg_out_op(TCGContext *s, TCGOpcode opc,
const TCGArg args[TCG_MAX_OP_ARGS],
const int const_args[TCG_MAX_OP_ARGS])
{
TCGArg a0 = args[0];
switch (opc) {
case INDEX_op_mb:
tcg_out_mb(s, a0);
break;
case INDEX_op_goto_ptr:
tcg_out_opc_jirl(s, TCG_REG_ZERO, a0, 0);
break;
case INDEX_op_mov_i32: /* Always emitted via tcg_out_mov. */
case INDEX_op_mov_i64:
default:
g_assert_not_reached();
}
}
static TCGConstraintSetIndex tcg_target_op_def(TCGOpcode op)
{
switch (op) {
case INDEX_op_goto_ptr:
return C_O0_I1(r);
default:
g_assert_not_reached();
}
}