Hi Claudio,
here are some minor tweaks and comments.
You work is very interesting and will form a good basis for further
improvements. Thanks!
> diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c
> new file mode 100644
> index 0000000..da859c7
> --- /dev/null
> +++ b/tcg/aarch64/tcg-target.c
> @@ -0,0 +1,1185 @@
> +/*
> + * Initial TCG Implementation for aarch64
> + *
> + * Copyright (c) 2013 Huawei Technologies Duesseldorf GmbH
> + * Written by Claudio Fontana
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * (at your option) any later version.
> + *
> + * See the COPYING file in the top-level directory for details.
> + */
> +
> +#ifdef TARGET_WORDS_BIGENDIAN
> +#error "Sorry, bigendian target not supported yet."
> +#endif /* TARGET_WORDS_BIGENDIAN */
> +
> +#ifndef NDEBUG
> +static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
> + "%x0", "%x1", "%x2", "%x3", "%x4", "%x5", "%x6", "%x7",
> + "%x8", "%x9", "%x10", "%x11", "%x12", "%x13", "%x14", "%x15",
> + "%x16", "%x17", "%x18", "%x19", "%x20", "%x21", "%x22", "%x23",
> + "%x24", "%x25", "%x26", "%x27", "%x28",
> + "%fp", /* frame pointer */
> + "%lr", /* link register */
> + "%sp", /* stack pointer */
> +};
> +#endif /* NDEBUG */
> +
> +static const int tcg_target_reg_alloc_order[] = {
> + TCG_REG_X20, TCG_REG_X21, TCG_REG_X22, TCG_REG_X23,
> + TCG_REG_X24, TCG_REG_X25, TCG_REG_X26, TCG_REG_X27,
> + TCG_REG_X28,
> +
> + TCG_REG_X9, TCG_REG_X10, TCG_REG_X11, TCG_REG_X12,
> + TCG_REG_X13, TCG_REG_X14, TCG_REG_X15,
> + TCG_REG_X16, TCG_REG_X17,
> +
> + TCG_REG_X18, TCG_REG_X19, /* will not use these, see tcg_target_init */
> +
> + TCG_REG_X0, TCG_REG_X1, TCG_REG_X2, TCG_REG_X3,
> + TCG_REG_X4, TCG_REG_X5, TCG_REG_X6, TCG_REG_X7,
> +
> + TCG_REG_X8, /* will not use, see tcg_target_init */
> +};
> +
> +static const int tcg_target_call_iarg_regs[8] = {
> + TCG_REG_X0, TCG_REG_X1, TCG_REG_X2, TCG_REG_X3,
> + TCG_REG_X4, TCG_REG_X5, TCG_REG_X6, TCG_REG_X7
> +};
> +static const int tcg_target_call_oarg_regs[1] = {
> + TCG_REG_X0
> +};
> +
> +#define TCG_REG_TMP TCG_REG_X8
> +
> +static inline void reloc_pc26(void *code_ptr, tcg_target_long target)
> +{
> + tcg_target_long offset; uint32_t insn;
> + offset = (target - (tcg_target_long)code_ptr) / 4;
> + offset &= 0x03ffffff;
> + /* read instruction, mask away previous PC_REL26 parameter contents,
> + set the proper offset, then write back the instruction. */
> + insn = *(uint32_t *)code_ptr;
> + insn = (insn & 0xfc000000) | offset;
> + *(uint32_t *)code_ptr = insn;
> +}
> +
> +static inline void reloc_pc19(void *code_ptr, tcg_target_long target)
> +{
> + tcg_target_long offset; uint32_t insn;
> + offset = (target - (tcg_target_long)code_ptr) / 4;
> + offset &= 0x07ffff;
> + /* read instruction, mask away previous PC_REL19 parameter contents,
> + set the proper offset, then write back the instruction. */
> + insn = *(uint32_t *)code_ptr;
> + insn = (insn & 0xff00001f) | offset << 5; /* lower 5 bits = condition */
The comment is wrong: only the lower 4 bits form the condition.
> + *(uint32_t *)code_ptr = insn;
> +}
> +
> +static inline void patch_reloc(uint8_t *code_ptr, int type,
> + tcg_target_long value, tcg_target_long addend)
> +{
> + switch (type) {
> + case R_AARCH64_JUMP26:
> + case R_AARCH64_CALL26:
> + reloc_pc26(code_ptr, value);
> + break;
> + case R_AARCH64_CONDBR19:
> + reloc_pc19(code_ptr, value);
> + break;
> +
> + default:
> + tcg_abort();
> + }
> +}
> +
> +/* parse target specific constraints */
> +static int target_parse_constraint(TCGArgConstraint *ct,
> + const char **pct_str)
> +{
> + const char *ct_str = *pct_str;
> +
> + switch (ct_str[0]) {
> + case 'r':
> + ct->ct |= TCG_CT_REG;
> + tcg_regset_set32(ct->u.regs, 0, (1ULL << TCG_TARGET_NB_REGS) - 1);
> + break;
> + case 'l': /* qemu_ld / qemu_st address, data_reg */
> + ct->ct |= TCG_CT_REG;
> + tcg_regset_set32(ct->u.regs, 0, (1ULL << TCG_TARGET_NB_REGS) - 1);
> +#ifdef CONFIG_SOFTMMU
> + /* x0 and x1 will be overwritten when reading the tlb entry,
> + and x2, and x3 for helper args, better to avoid using them. */
> + tcg_regset_reset_reg(ct->u.regs, TCG_REG_X0);
> + tcg_regset_reset_reg(ct->u.regs, TCG_REG_X1);
> + tcg_regset_reset_reg(ct->u.regs, TCG_REG_X2);
> + tcg_regset_reset_reg(ct->u.regs, TCG_REG_X3);
> +#endif
> + break;
> + default:
> + return -1;
> + }
> +
> + ct_str++;
> + *pct_str = ct_str;
> + return 0;
> +}
> +
> +static inline int tcg_target_const_match(tcg_target_long val,
> + const TCGArgConstraint *arg_ct)
> +{
> + int ct = arg_ct->ct;
> +
> + if (ct & TCG_CT_CONST) {
> + return 1;
> + }
> +
> + return 0;
> +}
> +
> +enum aarch64_cond_code {
> + COND_EQ = 0x0,
> + COND_NE = 0x1,
> + COND_CS = 0x2, /* Unsigned greater or equal */
> + COND_HS = COND_CS, /* ALIAS greater or equal */
> + COND_CC = 0x3, /* Unsigned less than */
> + COND_LO = COND_CC, /* ALIAS Lower */
> + COND_MI = 0x4, /* Negative */
> + COND_PL = 0x5, /* Zero or greater */
> + COND_VS = 0x6, /* Overflow */
> + COND_VC = 0x7, /* No overflow */
> + COND_HI = 0x8, /* Unsigned greater than */
> + COND_LS = 0x9, /* Unsigned less or equal */
> + COND_GE = 0xa,
> + COND_LT = 0xb,
> + COND_GT = 0xc,
> + COND_LE = 0xd,
> + COND_AL = 0xe,
> + COND_NV = 0xf, /* behaves like COND_AL here */
> +};
> +
> +static const enum aarch64_cond_code tcg_cond_to_aarch64[] = {
> + [TCG_COND_EQ] = COND_EQ,
> + [TCG_COND_NE] = COND_NE,
> + [TCG_COND_LT] = COND_LT,
> + [TCG_COND_GE] = COND_GE,
> + [TCG_COND_LE] = COND_LE,
> + [TCG_COND_GT] = COND_GT,
> + /* unsigned */
> + [TCG_COND_LTU] = COND_LO,
> + [TCG_COND_GTU] = COND_HI,
> + [TCG_COND_GEU] = COND_HS,
> + [TCG_COND_LEU] = COND_LS,
> +};
> +
> +/* opcodes for LDR / STR instructions with base + simm9 addressing */
> +enum aarch64_ldst_op_data { /* size of the data moved */
> + LDST_8 = 0x38,
> + LDST_16 = 0x78,
> + LDST_32 = 0xb8,
> + LDST_64 = 0xf8,
> +};
> +enum aarch64_ldst_op_type { /* type of operation */
> + LDST_ST = 0x0, /* store */
> + LDST_LD = 0x4, /* load */
> + LDST_LD_S_X = 0x8, /* load and sign-extend into Xt */
> + LDST_LD_S_W = 0xc, /* load and sign-extend into Wt */
> +};
> +
> +enum aarch64_arith_opc {
> + ARITH_ADD = 0x0b,
> + ARITH_SUB = 0x4b,
> + ARITH_AND = 0x0a,
> + ARITH_OR = 0x2a,
> + ARITH_XOR = 0x4a
> +};
> +
> +enum aarch64_srr_opc {
> + SRR_SHL = 0x0,
> + SRR_SHR = 0x4,
> + SRR_SAR = 0x8,
> + SRR_ROR = 0xc
> +};
> +
> +static inline enum aarch64_ldst_op_data
> +aarch64_ldst_get_data(TCGOpcode tcg_op)
> +{
> + switch (tcg_op) {
> + case INDEX_op_ld8u_i32: case INDEX_op_ld8s_i32:
> + case INDEX_op_ld8u_i64: case INDEX_op_ld8s_i64:
> + case INDEX_op_st8_i32: case INDEX_op_st8_i64:
> + return LDST_8;
> +
> + case INDEX_op_ld16u_i32: case INDEX_op_ld16s_i32:
> + case INDEX_op_ld16u_i64: case INDEX_op_ld16s_i64:
> + case INDEX_op_st16_i32: case INDEX_op_st16_i64:
> + return LDST_16;
> +
> + case INDEX_op_ld_i32: case INDEX_op_st_i32:
> + case INDEX_op_ld32u_i64: case INDEX_op_ld32s_i64:
> + case INDEX_op_st32_i64:
> + return LDST_32;
> +
> + case INDEX_op_ld_i64: case INDEX_op_st_i64:
> + return LDST_64;
> +
> + default:
> + tcg_abort();
> + }
> +}
> +
> +static inline enum aarch64_ldst_op_type
> +aarch64_ldst_get_type(TCGOpcode tcg_op)
> +{
> + switch (tcg_op) {
> + case INDEX_op_st8_i32: case INDEX_op_st16_i32:
> + case INDEX_op_st8_i64: case INDEX_op_st16_i64:
> + case INDEX_op_st_i32:
> + case INDEX_op_st32_i64:
> + case INDEX_op_st_i64:
> + return LDST_ST;
> +
> + case INDEX_op_ld8u_i32: case INDEX_op_ld16u_i32:
> + case INDEX_op_ld8u_i64: case INDEX_op_ld16u_i64:
> + case INDEX_op_ld_i32:
> + case INDEX_op_ld32u_i64:
> + case INDEX_op_ld_i64:
> + return LDST_LD;
> +
> + case INDEX_op_ld8s_i32: case INDEX_op_ld16s_i32:
> + return LDST_LD_S_W;
> +
> + case INDEX_op_ld8s_i64: case INDEX_op_ld16s_i64:
> + case INDEX_op_ld32s_i64:
> + return LDST_LD_S_X;
> +
> + default:
> + tcg_abort();
> + }
> +}
> +
> +static inline uint32_t tcg_in32(TCGContext *s)
> +{
> + uint32_t v = *(uint32_t *)s->code_ptr;
> + return v;
> +}
> +
> +static inline void tcg_out_ldst_9(TCGContext *s,
> + enum aarch64_ldst_op_data op_data,
> + enum aarch64_ldst_op_type op_type,
> + int rd, int rn, tcg_target_long offset)
> +{
> + /* use LDUR with BASE register with 9bit signed unscaled offset */
> + unsigned int mod, off;
> +
> + if (offset < 0) {
> + off = (256 + offset);
> + mod = 0x1;
> +
Extra blank line.
> + } else {
> + off = offset;
> + mod = 0x0;
> + }
> +
> + mod |= op_type;
> + tcg_out32(s, op_data << 24 | mod << 20 | off << 12 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_movr(TCGContext *s, int ext, int rd, int source)
> +{
> + /* register to register move using MOV (shifted register with no shift)
> */
> + /* using MOV 0x2a0003e0 | (shift).. */
> + unsigned int base = ext ? 0xaa0003e0 : 0x2a0003e0;
> + tcg_out32(s, base | source << 16 | rd);
> +}
See comment below for tcg_out_movr_sp.
> +static inline void tcg_out_movi32(TCGContext *s, int ext, int rd,
> + uint32_t value)
> +{
> + uint32_t half, base, movk = 0;
> + if (!value) {
> + tcg_out_movr(s, ext, rd, TCG_REG_XZR);
> + return;
> + }
> + /* construct halfwords of the immediate with MOVZ with LSL */
> + /* using MOVZ 0x52800000 | extended reg.. */
> + base = ext ? 0xd2800000 : 0x52800000;
> +
> + half = value & 0xffff;
> + if (half) {
> + tcg_out32(s, base | half << 5 | rd);
> + movk = 0x20000000; /* morph next MOVZ into MOVK */
> + }
> +
> + half = value >> 16;
> + if (half) { /* add shift 0x00200000. Op can be MOVZ or MOVK */
> + tcg_out32(s, base | movk | 0x00200000 | half << 5 | rd);
> + }
> +}
> +
> +static inline void tcg_out_movi64(TCGContext *s, int rd, uint64_t value)
> +{
> + uint32_t half, base, movk = 0, shift = 0;
> + if (!value) {
> + tcg_out_movr(s, 1, rd, TCG_REG_XZR);
> + return;
> + }
> + /* construct halfwords of the immediate with MOVZ with LSL */
> + /* using MOVZ 0x52800000 | extended reg.. */
> + base = 0xd2800000;
> +
> + while (value) {
> + half = value & 0xffff;
> + if (half) {
> + /* Op can be MOVZ or MOVK */
> + tcg_out32(s, base | movk | shift | half << 5 | rd);
> + if (!movk) {
> + movk = 0x20000000; /* morph next MOVZs into MOVKs */
> + }
> + }
> + value >>= 16;
> + shift += 0x00200000;
> + }
> +}
> +
> +static inline void tcg_out_ldst_r(TCGContext *s,
> + enum aarch64_ldst_op_data op_data,
> + enum aarch64_ldst_op_type op_type,
> + int rd, int base, int regoff)
> +{
> + /* load from memory to register using base + 64bit register offset */
> + /* using f.e. STR Wt, [Xn, Xm] 0xb8600800|(regoff << 16)|(base << 5)|rd
> */
> + /* the 0x6000 is for the "no extend field" */
> + tcg_out32(s, 0x00206800
> + | op_data << 24 | op_type << 20 | regoff << 16 | base << 5 |
> rd);
> +}
> +
> +/* solve the whole ldst problem */
> +static inline void tcg_out_ldst(TCGContext *s, enum aarch64_ldst_op_data
> data,
> + enum aarch64_ldst_op_type type,
> + int rd, int rn, tcg_target_long offset)
> +{
> + if (offset > -256 && offset < 256) {
Offset >= -256.
> + tcg_out_ldst_9(s, data, type, rd, rn, offset);
> +
> + } else {
> + tcg_out_movi64(s, TCG_REG_TMP, offset);
> + tcg_out_ldst_r(s, data, type, rd, rn, TCG_REG_TMP);
> + }
> +}
> +
> +static inline void tcg_out_movi(TCGContext *s, TCGType type,
> + TCGReg rd, tcg_target_long value)
> +{
> + if (type == TCG_TYPE_I64) {
> + tcg_out_movi64(s, rd, value);
> + } else {
> + tcg_out_movi32(s, 0, rd, value);
> + }
> +}
> +
> +/* mov alias implemented with add immediate, useful to move to/from SP */
> +static inline void tcg_out_movr_sp(TCGContext *s, int ext, int rd, int rn)
> +{
> + /* using ADD 0x11000000 | (ext) | rn << 5 | rd */
> + unsigned int base = ext ? 0x91000000 : 0x11000000;
> + tcg_out32(s, base | rn << 5 | rd);
> +}
Couldn't this function be used for tcg_out_movr too? That shouldn't
be an issue unless you want to use ZR as source or destination (this
will be true if you change tcg_out_movi according to Richard's
proposal).
> +static inline void tcg_out_mov(TCGContext *s,
> + TCGType type, TCGReg ret, TCGReg arg)
> +{
> + if (ret != arg) {
> + tcg_out_movr(s, type == TCG_TYPE_I64, ret, arg);
> + }
> +}
> +
> +static inline void tcg_out_ld(TCGContext *s, TCGType type, TCGReg arg,
> + TCGReg arg1, tcg_target_long arg2)
> +{
> + tcg_out_ldst(s, (type == TCG_TYPE_I64) ? LDST_64 : LDST_32, LDST_LD,
> + arg, arg1, arg2);
> +}
> +
> +static inline void tcg_out_st(TCGContext *s, TCGType type, TCGReg arg,
> + TCGReg arg1, tcg_target_long arg2)
> +{
> + tcg_out_ldst(s, (type == TCG_TYPE_I64) ? LDST_64 : LDST_32, LDST_ST,
> + arg, arg1, arg2);
> +}
> +
> +static inline void tcg_out_arith(TCGContext *s, enum aarch64_arith_opc opc,
> + int ext, int rd, int rn, int rm)
> +{
> + /* Using shifted register arithmetic operations */
> + /* if extended registry operation (64bit) just or with 0x80 << 24 */
> + unsigned int base = ext ? (0x80 | opc) << 24 : opc << 24;
> + tcg_out32(s, base | rm << 16 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_mul(TCGContext *s, int ext, int rd, int rn, int
> rm)
> +{
> + /* Using MADD 0x1b000000 with Ra = wzr alias MUL 0x1b007c00 */
> + unsigned int base = ext ? 0x9b007c00 : 0x1b007c00;
> + tcg_out32(s, base | rm << 16 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_shiftrot_reg(TCGContext *s,
> + enum aarch64_srr_opc opc, int ext,
> + int rd, int rn, int rm)
> +{
> + /* using 2-source data processing instructions 0x1ac02000 */
> + unsigned int base = ext ? 0x9ac02000 : 0x1ac02000;
> + tcg_out32(s, base | rm << 16 | opc << 8 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_ubfm(TCGContext *s, int ext,
> + int rd, int rn, unsigned int a, unsigned int
> b)
> +{
> + /* Using UBFM 0x53000000 Wd, Wn, a, b - ext encoding requires the 0x4 */
> + unsigned int base = ext ? 0xd3400000 : 0x53000000;
> + tcg_out32(s, base | a << 16 | b << 10 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_sbfm(TCGContext *s, int ext,
> + int rd, int rn, unsigned int a, unsigned int
> b)
> +{
> + /* Using SBFM 0x13000000 Wd, Wn, a, b - ext encoding requires the 0x4 */
> + unsigned int base = ext ? 0x93400000 : 0x13000000;
> + tcg_out32(s, base | a << 16 | b << 10 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_extr(TCGContext *s, int ext,
> + int rd, int rn, int rm, unsigned int a)
> +{
> + /* Using EXTR 0x13800000 Wd, Wn, Wm, a - ext encoding requires the 0x4 */
> + unsigned int base = ext ? 0x93c00000 : 0x13800000;
> + tcg_out32(s, base | rm << 16 | a << 10 | rn << 5 | rd);
> +}
> +
> +static inline void tcg_out_shl(TCGContext *s, int ext,
> + int rd, int rn, unsigned int m)
> +{
> + int bits, max;
> + bits = ext ? 64 : 32;
> + max = bits - 1;
> + tcg_out_ubfm(s, ext, rd, rn, bits - (m & max), max - (m & max));
> +}
> +
> +static inline void tcg_out_shr(TCGContext *s, int ext,
> + int rd, int rn, unsigned int m)
> +{
> + int max = ext ? 63 : 31;
> + tcg_out_ubfm(s, ext, rd, rn, m & max, max);
> +}
> +
> +static inline void tcg_out_sar(TCGContext *s, int ext,
> + int rd, int rn, unsigned int m)
> +{
> + int max = ext ? 63 : 31;
> + tcg_out_sbfm(s, ext, rd, rn, m & max, max);
> +}
> +
> +static inline void tcg_out_rotr(TCGContext *s, int ext,
> + int rd, int rn, unsigned int m)
> +{
> + int max = ext ? 63 : 31;
> + tcg_out_extr(s, ext, rd, rn, rn, m & max);
> +}
> +
> +static inline void tcg_out_rotl(TCGContext *s, int ext,
> + int rd, int rn, unsigned int m)
> +{
> + int bits, max;
> + bits = ext ? 64 : 32;
> + max = bits - 1;
> + tcg_out_extr(s, ext, rd, rn, rn, bits - (m & max));
> +}
> +
> +static inline void tcg_out_cmp(TCGContext *s, int ext,
> + int rn, int rm)
> +{
> + /* Using CMP alias SUBS wzr, Wn, Wm */
> + unsigned int base = ext ? 0xeb00001f : 0x6b00001f;
> + tcg_out32(s, base | rm << 16 | rn << 5);
> +}
> +
> +static inline void tcg_out_cset(TCGContext *s, int ext,
> + int rd, TCGCond c)
> +{
> + /* Using CSET alias of CSINC 0x1a800400 Xd, XZR, XZR, invert(cond) */
> + unsigned int base = ext ? 0x9a9f07e0 : 0x1a9f07e0;
> + tcg_out32(s, base | tcg_cond_to_aarch64[tcg_invert_cond(c)] << 12 | rd);
> +}
> +
> +static inline void tcg_out_goto(TCGContext *s, tcg_target_long target)
> +{
> + tcg_target_long offset;
> + offset = (target - (tcg_target_long)s->code_ptr) / 4;
> +
> + if (offset <= -0x02000000 || offset >= 0x02000000) {
offset < -0x02000000
> + /* out of 26bit range */
> + tcg_abort();
> + }
> +
> + tcg_out32(s, 0x14000000 | (offset & 0x03ffffff));
> +}
> +
> +static inline void tcg_out_goto_noaddr(TCGContext *s)
> +{
> + /* We pay attention here to not modify the branch target by
> + reading from the buffer. This ensure that caches and memory are
> + kept coherent during retranslation.
> + Mask away possible garbage in the high bits for the first translation,
> + while keeping the offset bits for retranslation. */
> + uint32_t insn;
> + insn = (tcg_in32(s) & 0x03ffffff) | 0x14000000;
> + tcg_out32(s, insn);
> +}
> +
> +static inline void tcg_out_goto_cond_noaddr(TCGContext *s, TCGCond c)
> +{
> + /* see comments in tcg_out_goto_noaddr */
> + uint32_t insn;
> + insn = tcg_in32(s) & (0x07ffff << 5);
> + insn |= 0x54000000 | tcg_cond_to_aarch64[c];
> + tcg_out32(s, insn);
> +}
> +
> +static inline void tcg_out_goto_cond(TCGContext *s, TCGCond c,
> + tcg_target_long target)
> +{
> + tcg_target_long offset;
> + offset = (target - (tcg_target_long)s->code_ptr) / 4;
> +
> + if (offset <= -0x3ffff || offset >= 0x3ffff) {
offset < -0x40000
> + /* out of 19bit range */
> + tcg_abort();
> + }
> +
> + offset &= 0x7ffff;
> + tcg_out32(s, 0x54000000 | tcg_cond_to_aarch64[c] | offset << 5);
> +}
> +
> +static inline void tcg_out_callr(TCGContext *s, int reg)
> +{
> + tcg_out32(s, 0xd63f0000 | reg << 5);
> +}
> +
> +static inline void tcg_out_gotor(TCGContext *s, int reg)
> +{
> + tcg_out32(s, 0xd61f0000 | reg << 5);
> +}
> +
> +static inline void tcg_out_call(TCGContext *s, tcg_target_long target)
> +{
> + tcg_target_long offset;
> +
> + offset = (target - (tcg_target_long)s->code_ptr) / 4;
> +
> + if (offset <= -0x02000000 || offset >= 0x02000000) { /* out of 26bit rng
> */
offset < -0x02000000
> + tcg_out_movi64(s, TCG_REG_TMP, target);
> + tcg_out_callr(s, TCG_REG_TMP);
> +
Extra blank line.
> + } else {
> + tcg_out32(s, 0x94000000 | (offset & 0x03ffffff));
> + }
> +}
> +
> +/* test a register against a bit pattern made of pattern_n repeated 1s.
> + For example, to test against 0111b (0x07), pass pattern_n = 3 */
> +static inline void tcg_out_tst(TCGContext *s, int ext, int rn,
> + tcg_target_ulong pattern_n)
> +{
> + /* using TST alias of ANDS XZR, Xn,#bimm64 0x7200001f. Ext requires 4. */
> + unsigned int base = ext ? 0xf240001f : 0x7200001f;
> + tcg_out32(s, base | (pattern_n - 1) << 10 | rn << 5);
> +}
You probably should protect against pattern_n == 0.
Note this function is currently unused.
> +static inline void tcg_out_ret(TCGContext *s)
> +{
> + /* emit RET { LR } */
> + tcg_out32(s, 0xd65f03c0);
> +}
> +
> +void aarch64_tb_set_jmp_target(uintptr_t jmp_addr, uintptr_t addr)
> +{
> + tcg_target_long target, offset;
> + target = (tcg_target_long)addr;
> + offset = (target - (tcg_target_long)jmp_addr) / 4;
> +
> + if (offset <= -0x02000000 || offset >= 0x02000000) {
offset < -0x02000000
> + /* out of 26bit range */
> + tcg_abort();
> + }
> +
> + patch_reloc((uint8_t *)jmp_addr, R_AARCH64_JUMP26, target, 0);
> + flush_icache_range(jmp_addr, jmp_addr + 4);
> +}
> +
> +static inline void tcg_out_goto_label(TCGContext *s, int label_index)
> +{
> + TCGLabel *l = &s->labels[label_index];
> +
> + if (!l->has_value) {
> + tcg_out_reloc(s, s->code_ptr, R_AARCH64_JUMP26, label_index, 0);
> + tcg_out_goto_noaddr(s);
> +
> + } else {
> + tcg_out_goto(s, l->u.value);
> + }
> +}
> +
> +static inline void tcg_out_goto_label_cond(TCGContext *s,
> + TCGCond c, int label_index)
> +{
> + TCGLabel *l = &s->labels[label_index];
> +
> + if (!l->has_value) {
> + tcg_out_reloc(s, s->code_ptr, R_AARCH64_CONDBR19, label_index, 0);
> + tcg_out_goto_cond_noaddr(s, c);
> +
> + } else {
> + tcg_out_goto_cond(s, c, l->u.value);
> + }
> +}
> +
> +#ifdef CONFIG_SOFTMMU
> +#include "exec/softmmu_defs.h"
> +
> +/* helper signature: helper_ld_mmu(CPUState *env, target_ulong addr,
> + int mmu_idx) */
> +static const void * const qemu_ld_helpers[4] = {
> + helper_ldb_mmu,
> + helper_ldw_mmu,
> + helper_ldl_mmu,
> + helper_ldq_mmu,
> +};
> +
> +/* helper signature: helper_st_mmu(CPUState *env, target_ulong addr,
> + uintxx_t val, int mmu_idx) */
> +static const void * const qemu_st_helpers[4] = {
> + helper_stb_mmu,
> + helper_stw_mmu,
> + helper_stl_mmu,
> + helper_stq_mmu,
> +};
> +
> +#endif /* CONFIG_SOFTMMU */
> +
> +static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args, int opc)
> +{
> + int addr_reg, data_reg;
> +#ifdef CONFIG_SOFTMMU
> + int mem_index, s_bits;
> +#endif
> + data_reg = args[0];
> + addr_reg = args[1];
> +
> +#ifdef CONFIG_SOFTMMU
> + mem_index = args[2];
> + s_bits = opc & 3;
> +
> + /* TODO: insert TLB lookup here */
> +
> +# if CPU_TLB_BITS > 8
> +# error "CPU_TLB_BITS too large"
> +# endif
> +
> + /* all arguments passed via registers */
> + tcg_out_movr(s, 1, TCG_REG_X0, TCG_AREG0);
> + tcg_out_movr(s, 1, TCG_REG_X1, addr_reg);
> + tcg_out_movi32(s, 0, TCG_REG_X2, mem_index);
> +
> + tcg_out_movi64(s, TCG_REG_TMP, (uint64_t)qemu_ld_helpers[s_bits]);
> + tcg_out_callr(s, TCG_REG_TMP);
> +
> + if (opc & 0x04) { /* sign extend */
> + unsigned int bits; bits = 8 * (1 << s_bits) - 1;
> + tcg_out_sbfm(s, 1, data_reg, TCG_REG_X0, 0, bits); /* 7|15|31 */
> +
> + } else {
> + tcg_out_movr(s, 1, data_reg, TCG_REG_X0);
> + }
> +
> +#else /* !CONFIG_SOFTMMU */
> + tcg_abort(); /* TODO */
> +#endif
> +}
> +
> +static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, int opc)
> +{
> + int addr_reg, data_reg;
> +#ifdef CONFIG_SOFTMMU
> + int mem_index, s_bits;
> +#endif
> + data_reg = args[0];
> + addr_reg = args[1];
> +
> +#ifdef CONFIG_SOFTMMU
> + mem_index = args[2];
> + s_bits = opc & 3;
> +
> + /* TODO: here we should generate something like the following:
> + * shr x8, addr_reg, #TARGET_PAGE_BITS
> + * and x0, x8, #(CPU_TLB_SIZE - 1) @ Assumption: CPU_TLB_BITS <= 8
> + * add x0, env, x0 lsl #CPU_TLB_ENTRY_BITS
> + * test ... XXX
> + */
> +# if CPU_TLB_BITS > 8
> +# error "CPU_TLB_BITS too large"
> +# endif
> +
> + /* all arguments passed via registers */
> + tcg_out_movr(s, 1, TCG_REG_X0, TCG_AREG0);
> + tcg_out_movr(s, 1, TCG_REG_X1, addr_reg);
> + tcg_out_movr(s, 1, TCG_REG_X2, data_reg);
> + tcg_out_movi32(s, 0, TCG_REG_X3, mem_index);
> +
> + tcg_out_movi64(s, TCG_REG_TMP, (uint64_t)qemu_st_helpers[s_bits]);
> + tcg_out_callr(s, TCG_REG_TMP);
> +
> +#else /* !CONFIG_SOFTMMU */
> + tcg_abort(); /* TODO */
> +#endif
> +}
> +
> +static uint8_t *tb_ret_addr;
> +
> +/* callee stack use example:
> + stp x29, x30, [sp,#-32]!
> + mov x29, sp
> + stp x1, x2, [sp,#16]
> + ...
> + ldp x1, x2, [sp,#16]
> + ldp x29, x30, [sp],#32
> + ret
> +*/
> +
> +/* push r1 and r2, and alloc stack space for a total of
> + alloc_n elements (1 element=16 bytes, must be between 1 and 31. */
> +static inline void tcg_out_push_pair(TCGContext *s,
> + TCGReg r1, TCGReg r2, int alloc_n)
> +{
> + /* using indexed scaled simm7 STP 0x28800000 | (ext) | 0x01000000
> (pre-idx)
> + | alloc_n * (-1) << 16 | r2 << 10 | sp(31) << 5 | r1 */
> + assert(alloc_n > 0 && alloc_n < 0x20);
> + alloc_n = (-alloc_n) & 0x3f;
> + tcg_out32(s, 0xa98003e0 | alloc_n << 16 | r2 << 10 | r1);
> +}
> +
> +/* dealloc stack space for a total of alloc_n elements and pop r1, r2. */
> +static inline void tcg_out_pop_pair(TCGContext *s,
> + TCGReg r1, TCGReg r2, int alloc_n)
> +{
> + /* using indexed scaled simm7 LDP 0x28c00000 | (ext) | nothing (post-idx)
> + | alloc_n << 16 | r2 << 10 | sp(31) << 5 | r1 */
> + assert(alloc_n > 0 && alloc_n < 0x20);
> + tcg_out32(s, 0xa8c003e0 | alloc_n << 16 | r2 << 10 | r1);
> +}
> +
> +static inline void tcg_out_store_pair(TCGContext *s,
> + TCGReg r1, TCGReg r2, int idx)
> +{
> + /* using register pair offset simm7 STP 0x29000000 | (ext)
> + | idx << 16 | r2 << 10 | fp(29) << 5 | r1 */
> + assert(idx > 0 && idx < 0x20);
> + tcg_out32(s, 0xa90003a0 | idx << 16 | r2 << 10 | r1);
> +}
> +
> +static inline void tcg_out_load_pair(TCGContext *s,
> + TCGReg r1, TCGReg r2, int idx)
> +{
> + /* using register pair offset simm7 LDP 0x29400000 | (ext)
> + | idx << 16 | r2 << 10 | fp(29) << 5 | r1 */
> + assert(idx > 0 && idx < 0x20);
> + tcg_out32(s, 0xa94003a0 | idx << 16 | r2 << 10 | r1);
> +}
> +
> +static void tcg_out_op(TCGContext *s, TCGOpcode opc,
> + const TCGArg *args, const int *const_args)
> +{
> + int ext = 0;
> +
> + switch (opc) {
> + case INDEX_op_exit_tb:
> + tcg_out_movi64(s, TCG_REG_X0, args[0]); /* load retval in X0 */
> + tcg_out_goto(s, (tcg_target_long)tb_ret_addr);
> + break;
> +
> + case INDEX_op_goto_tb:
> +#ifndef USE_DIRECT_JUMP
> +#error "USE_DIRECT_JUMP required for aarch64"
> +#endif
> + assert(s->tb_jmp_offset != NULL); /* consistency for USE_DIRECT_JUMP
> */
> + s->tb_jmp_offset[args[0]] = s->code_ptr - s->code_buf;
> + /* actual branch destination will be patched by
> + aarch64_tb_set_jmp_target later, beware retranslation. */
> + tcg_out_goto_noaddr(s);
> + s->tb_next_offset[args[0]] = s->code_ptr - s->code_buf;
> + break;
> +
> + case INDEX_op_call:
> + if (const_args[0]) {
> + tcg_out_call(s, args[0]);
> + } else {
> + tcg_out_callr(s, args[0]);
> + }
> + break;
> +
> + case INDEX_op_br:
> + tcg_out_goto_label(s, args[0]);
> + break;
> +
> + case INDEX_op_ld_i32:
> + case INDEX_op_ld_i64:
> + case INDEX_op_st_i32:
> + case INDEX_op_st_i64:
> + case INDEX_op_ld8u_i32:
> + case INDEX_op_ld8s_i32:
> + case INDEX_op_ld16u_i32:
> + case INDEX_op_ld16s_i32:
> + case INDEX_op_ld8u_i64:
> + case INDEX_op_ld8s_i64:
> + case INDEX_op_ld16u_i64:
> + case INDEX_op_ld16s_i64:
> + case INDEX_op_ld32u_i64:
> + case INDEX_op_ld32s_i64:
> + case INDEX_op_st8_i32:
> + case INDEX_op_st8_i64:
> + case INDEX_op_st16_i32:
> + case INDEX_op_st16_i64:
> + case INDEX_op_st32_i64:
> + tcg_out_ldst(s, aarch64_ldst_get_data(opc),
> aarch64_ldst_get_type(opc),
> + args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_mov_i64: ext = 1;
> + case INDEX_op_mov_i32:
> + tcg_out_movr(s, ext, args[0], args[1]);
> + break;
> +
> + case INDEX_op_movi_i64:
> + tcg_out_movi64(s, args[0], args[1]);
> + break;
> +
> + case INDEX_op_movi_i32:
> + tcg_out_movi32(s, 0, args[0], args[1]);
> + break;
> +
> + case INDEX_op_add_i64: ext = 1;
> + case INDEX_op_add_i32:
> + tcg_out_arith(s, ARITH_ADD, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_sub_i64: ext = 1;
> + case INDEX_op_sub_i32:
> + tcg_out_arith(s, ARITH_SUB, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_and_i64: ext = 1;
> + case INDEX_op_and_i32:
> + tcg_out_arith(s, ARITH_AND, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_or_i64: ext = 1;
> + case INDEX_op_or_i32:
> + tcg_out_arith(s, ARITH_OR, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_xor_i64: ext = 1;
> + case INDEX_op_xor_i32:
> + tcg_out_arith(s, ARITH_XOR, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_mul_i64: ext = 1;
> + case INDEX_op_mul_i32:
> + tcg_out_mul(s, ext, args[0], args[1], args[2]);
> + break;
> +
> + case INDEX_op_shl_i64: ext = 1;
> + case INDEX_op_shl_i32:
> + if (const_args[2]) { /* LSL / UBFM Wd, Wn, (32 - m) */
> + tcg_out_shl(s, ext, args[0], args[1], args[2]);
> + } else { /* LSL / LSLV */
> + tcg_out_shiftrot_reg(s, SRR_SHL, ext, args[0], args[1], args[2]);
> + }
> + break;
> +
> + case INDEX_op_shr_i64: ext = 1;
> + case INDEX_op_shr_i32:
> + if (const_args[2]) { /* LSR / UBFM Wd, Wn, m, 31 */
> + tcg_out_shr(s, ext, args[0], args[1], args[2]);
> + } else { /* LSR / LSRV */
> + tcg_out_shiftrot_reg(s, SRR_SHR, ext, args[0], args[1], args[2]);
> + }
> + break;
> +
> + case INDEX_op_sar_i64: ext = 1;
> + case INDEX_op_sar_i32:
> + if (const_args[2]) { /* ASR / SBFM Wd, Wn, m, 31 */
> + tcg_out_sar(s, ext, args[0], args[1], args[2]);
> + } else { /* ASR / ASRV */
> + tcg_out_shiftrot_reg(s, SRR_SAR, ext, args[0], args[1], args[2]);
> + }
> + break;
> +
> + case INDEX_op_rotr_i64: ext = 1;
> + case INDEX_op_rotr_i32:
> + if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, m */
> + tcg_out_rotr(s, ext, args[0], args[1], args[2]);
> + } else { /* ROR / RORV */
> + tcg_out_shiftrot_reg(s, SRR_ROR, ext, args[0], args[1], args[2]);
> + }
> + break;
> +
> + case INDEX_op_rotl_i64: ext = 1;
> + case INDEX_op_rotl_i32: /* same as rotate right by (32 - m) */
> + if (const_args[2]) { /* ROR / EXTR Wd, Wm, Wm, 32 - m */
> + tcg_out_rotl(s, ext, args[0], args[1], args[2]);
> + } else {
> + tcg_out_arith(s, ARITH_SUB, ext, args[2], TCG_REG_XZR, args[2]);
> + tcg_out_shiftrot_reg(s, SRR_ROR, ext, args[0], args[1], args[2]);
> + }
> + break;
> +
> + case INDEX_op_brcond_i64: ext = 1;
> + case INDEX_op_brcond_i32: /* CMP 0, 1, cond(2), label 3 */
> + tcg_out_cmp(s, ext, args[0], args[1]);
> + tcg_out_goto_label_cond(s, args[2], args[3]);
> + break;
> +
> + case INDEX_op_setcond_i64: ext = 1;
> + case INDEX_op_setcond_i32:
> + tcg_out_cmp(s, ext, args[1], args[2]);
> + tcg_out_cset(s, ext, args[0], args[3]);
> + break;
> +
> + case INDEX_op_qemu_ld8u:
> + tcg_out_qemu_ld(s, args, 0 | 0);
> + break;
> + case INDEX_op_qemu_ld8s:
> + tcg_out_qemu_ld(s, args, 4 | 0);
> + break;
> + case INDEX_op_qemu_ld16u:
> + tcg_out_qemu_ld(s, args, 0 | 1);
> + break;
> + case INDEX_op_qemu_ld16s:
> + tcg_out_qemu_ld(s, args, 4 | 1);
> + break;
> + case INDEX_op_qemu_ld32u:
> + tcg_out_qemu_ld(s, args, 0 | 2);
> + break;
> + case INDEX_op_qemu_ld32s:
> + tcg_out_qemu_ld(s, args, 4 | 2);
> + break;
> + case INDEX_op_qemu_ld32:
> + tcg_out_qemu_ld(s, args, 0 | 2);
> + break;
> + case INDEX_op_qemu_ld64:
> + tcg_out_qemu_ld(s, args, 0 | 3);
> + break;
> + case INDEX_op_qemu_st8:
> + tcg_out_qemu_st(s, args, 0);
> + break;
> + case INDEX_op_qemu_st16:
> + tcg_out_qemu_st(s, args, 1);
> + break;
> + case INDEX_op_qemu_st32:
> + tcg_out_qemu_st(s, args, 2);
> + break;
> + case INDEX_op_qemu_st64:
> + tcg_out_qemu_st(s, args, 3);
> + break;
> +
> + default:
> + tcg_abort(); /* opcode not implemented */
> + }
> +}
> +
> +static const TCGTargetOpDef aarch64_op_defs[] = {
> + { INDEX_op_exit_tb, { } },
> + { INDEX_op_goto_tb, { } },
> + { INDEX_op_call, { "ri" } },
> + { INDEX_op_br, { } },
> +
> + { INDEX_op_mov_i32, { "r", "r" } },
> + { INDEX_op_mov_i64, { "r", "r" } },
> +
> + { INDEX_op_movi_i32, { "r" } },
> + { INDEX_op_movi_i64, { "r" } },
> +
> + { INDEX_op_ld8u_i32, { "r", "r" } },
> + { INDEX_op_ld8s_i32, { "r", "r" } },
> + { INDEX_op_ld16u_i32, { "r", "r" } },
> + { INDEX_op_ld16s_i32, { "r", "r" } },
> + { INDEX_op_ld_i32, { "r", "r" } },
> + { INDEX_op_ld8u_i64, { "r", "r" } },
> + { INDEX_op_ld8s_i64, { "r", "r" } },
> + { INDEX_op_ld16u_i64, { "r", "r" } },
> + { INDEX_op_ld16s_i64, { "r", "r" } },
> + { INDEX_op_ld32u_i64, { "r", "r" } },
> + { INDEX_op_ld32s_i64, { "r", "r" } },
> + { INDEX_op_ld_i64, { "r", "r" } },
> +
> + { INDEX_op_st8_i32, { "r", "r" } },
> + { INDEX_op_st16_i32, { "r", "r" } },
> + { INDEX_op_st_i32, { "r", "r" } },
> + { INDEX_op_st8_i64, { "r", "r" } },
> + { INDEX_op_st16_i64, { "r", "r" } },
> + { INDEX_op_st32_i64, { "r", "r" } },
> + { INDEX_op_st_i64, { "r", "r" } },
> +
> + { INDEX_op_add_i32, { "r", "r", "r" } },
> + { INDEX_op_add_i64, { "r", "r", "r" } },
> + { INDEX_op_sub_i32, { "r", "r", "r" } },
> + { INDEX_op_sub_i64, { "r", "r", "r" } },
> + { INDEX_op_mul_i32, { "r", "r", "r" } },
> + { INDEX_op_mul_i64, { "r", "r", "r" } },
> + { INDEX_op_and_i32, { "r", "r", "r" } },
> + { INDEX_op_and_i64, { "r", "r", "r" } },
> + { INDEX_op_or_i32, { "r", "r", "r" } },
> + { INDEX_op_or_i64, { "r", "r", "r" } },
> + { INDEX_op_xor_i32, { "r", "r", "r" } },
> + { INDEX_op_xor_i64, { "r", "r", "r" } },
> +
> + { INDEX_op_shl_i32, { "r", "r", "ri" } },
> + { INDEX_op_shr_i32, { "r", "r", "ri" } },
> + { INDEX_op_sar_i32, { "r", "r", "ri" } },
> + { INDEX_op_rotl_i32, { "r", "r", "ri" } },
> + { INDEX_op_rotr_i32, { "r", "r", "ri" } },
> + { INDEX_op_shl_i64, { "r", "r", "ri" } },
> + { INDEX_op_shr_i64, { "r", "r", "ri" } },
> + { INDEX_op_sar_i64, { "r", "r", "ri" } },
> + { INDEX_op_rotl_i64, { "r", "r", "ri" } },
> + { INDEX_op_rotr_i64, { "r", "r", "ri" } },
> +
> + { INDEX_op_brcond_i32, { "r", "r" } },
> + { INDEX_op_setcond_i32, { "r", "r", "r" } },
> + { INDEX_op_brcond_i64, { "r", "r" } },
> + { INDEX_op_setcond_i64, { "r", "r", "r" } },
> +
> + { INDEX_op_qemu_ld8u, { "r", "l" } },
> + { INDEX_op_qemu_ld8s, { "r", "l" } },
> + { INDEX_op_qemu_ld16u, { "r", "l" } },
> + { INDEX_op_qemu_ld16s, { "r", "l" } },
> + { INDEX_op_qemu_ld32u, { "r", "l" } },
> + { INDEX_op_qemu_ld32s, { "r", "l" } },
> +
> + { INDEX_op_qemu_ld32, { "r", "l" } },
> + { INDEX_op_qemu_ld64, { "r", "l" } },
> +
> + { INDEX_op_qemu_st8, { "l", "l" } },
> + { INDEX_op_qemu_st16, { "l", "l" } },
> + { INDEX_op_qemu_st32, { "l", "l" } },
> + { INDEX_op_qemu_st64, { "l", "l" } },
> + { -1 },
> +};
> +
> +static void tcg_target_init(TCGContext *s)
> +{
> +#if !defined(CONFIG_USER_ONLY)
> + /* fail safe */
> + if ((1ULL << CPU_TLB_ENTRY_BITS) != sizeof(CPUTLBEntry)) {
> + tcg_abort();
> + }
> +#endif
> + tcg_regset_set32(tcg_target_available_regs[TCG_TYPE_I32], 0, 0xffffffff);
> + tcg_regset_set32(tcg_target_available_regs[TCG_TYPE_I64], 0, 0xffffffff);
> +
> + tcg_regset_set32(tcg_target_call_clobber_regs, 0,
> + (1 << TCG_REG_X0) | (1 << TCG_REG_X1) |
> + (1 << TCG_REG_X2) | (1 << TCG_REG_X3) |
> + (1 << TCG_REG_X4) | (1 << TCG_REG_X5) |
> + (1 << TCG_REG_X6) | (1 << TCG_REG_X7) |
> + (1 << TCG_REG_X8) | (1 << TCG_REG_X9) |
> + (1 << TCG_REG_X10) | (1 << TCG_REG_X11) |
> + (1 << TCG_REG_X12) | (1 << TCG_REG_X13) |
> + (1 << TCG_REG_X14) | (1 << TCG_REG_X15) |
> + (1 << TCG_REG_X16) | (1 << TCG_REG_X17) |
> + (1 << TCG_REG_X18) | (1 << TCG_REG_LR));
> +
> + tcg_regset_clear(s->reserved_regs);
> + tcg_regset_set_reg(s->reserved_regs, TCG_REG_SP);
> + tcg_regset_set_reg(s->reserved_regs, TCG_REG_TMP);
> + tcg_regset_set_reg(s->reserved_regs, TCG_REG_X18); /* platform register
> */
> +
> + tcg_add_target_add_op_defs(aarch64_op_defs);
> +}
> +
> +static inline void tcg_out_addi(TCGContext *s,
> + int ext, int rd, int rn, unsigned int aimm)
> +{
> + /* add immediate aimm unsigned 12bit value (we use LSL 0 - no shift) */
> + /* using ADD 0x11000000 | (ext) | (aimm << 10) | (rn << 5) | rd */
> + unsigned int base = ext ? 0x91000000 : 0x11000000;
> + assert(aimm <= 0xfff);
> + tcg_out32(s, base | (aimm << 10) | (rn << 5) | rd);
> +}
> +
> +static inline void tcg_out_subi(TCGContext *s,
> + int ext, int rd, int rn, unsigned int aimm)
> +{
> + /* sub immediate aimm unsigned 12bit value (we use LSL 0 - no shift) */
> + /* using SUB 0x51000000 | (ext) | (aimm << 10) | (rn << 5) | rd */
> + unsigned int base = ext ? 0xd1000000 : 0x51000000;
> + assert(aimm <= 0xfff);
> + tcg_out32(s, base | (aimm << 10) | (rn << 5) | rd);
> +}
> +
> +static void tcg_target_qemu_prologue(TCGContext *s)
> +{
> + /* NB: frame sizes are in 16 byte stack units! */
> + int frame_size_callee_saved, frame_size_tcg_locals;
> + int r;
> +
> + /* save pairs (FP, LR) and (X19, X20) .. (X27, X28) */
> + frame_size_callee_saved = (1) + (TCG_REG_X28 - TCG_REG_X19) / 2 + 1;
> +
> + /* frame size requirement for TCG local variables */
> + frame_size_tcg_locals = TCG_STATIC_CALL_ARGS_SIZE
> + + CPU_TEMP_BUF_NLONGS * sizeof(long)
> + + (TCG_TARGET_STACK_ALIGN - 1);
> + frame_size_tcg_locals &= ~(TCG_TARGET_STACK_ALIGN - 1);
> + frame_size_tcg_locals /= TCG_TARGET_STACK_ALIGN;
> +
> + /* push (FP, LR) and update sp */
> + tcg_out_push_pair(s, TCG_REG_FP, TCG_REG_LR, frame_size_callee_saved);
> +
> + /* FP -> callee_saved */
> + tcg_out_movr_sp(s, 1, TCG_REG_FP, TCG_REG_SP);
> +
> + /* store callee-preserved regs x19..x28 using FP -> callee_saved */
> + for (r = TCG_REG_X19; r <= TCG_REG_X27; r += 2) {
> + int idx; idx = (r - TCG_REG_X19) / 2 + 1;
> + tcg_out_store_pair(s, r, r + 1, idx);
> + }
> +
> + /* make stack space for TCG locals */
> + tcg_out_subi(s, 1, TCG_REG_SP, TCG_REG_SP,
> + frame_size_tcg_locals * TCG_TARGET_STACK_ALIGN);
> + /* inform TCG about how to find TCG locals with register, offset, size */
> + tcg_set_frame(s, TCG_REG_SP, TCG_STATIC_CALL_ARGS_SIZE,
> + CPU_TEMP_BUF_NLONGS * sizeof(long));
> +
> + tcg_out_mov(s, TCG_TYPE_PTR, TCG_AREG0, tcg_target_call_iarg_regs[0]);
> + tcg_out_gotor(s, tcg_target_call_iarg_regs[1]);
> +
> + tb_ret_addr = s->code_ptr;
> +
> + /* remove TCG locals stack space */
> + tcg_out_addi(s, 1, TCG_REG_SP, TCG_REG_SP,
> + frame_size_tcg_locals * TCG_TARGET_STACK_ALIGN);
> +
> + /* restore registers x19..x28.
> + FP must be preserved, so it still points to callee_saved area */
> + for (r = TCG_REG_X19; r <= TCG_REG_X27; r += 2) {
> + int idx; idx = (r - TCG_REG_X19) / 2 + 1;
> + tcg_out_load_pair(s, r, r + 1, idx);
> + }
> +
> + /* pop (FP, LR), restore SP to previous frame, return */
> + tcg_out_pop_pair(s, TCG_REG_FP, TCG_REG_LR, frame_size_callee_saved);
> + tcg_out_ret(s);
> +}
Laurent
