// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2016-2018 Netronome Systems, Inc. */

#define pr_fmt(fmt)     "NFP net bpf: " fmt

#include <linux/bug.h>
#include <linux/bpf.h>
#include <linux/filter.h>
#include <linux/kernel.h>
#include <linux/pkt_cls.h>
#include <linux/reciprocal_div.h>
#include <linux/unistd.h>

#include "main.h"
#include "../nfp_asm.h"
#include "../nfp_net_ctrl.h"

/* --- NFP prog --- */
/* Foreach "multiple" entries macros provide pos and next<n> pointers.
 * It's safe to modify the next pointers (but not pos).
 */
#define nfp_for_each_insn_walk2(nfp_prog, pos, next)                    \
        for (pos = list_first_entry(&(nfp_prog)->insns, typeof(*pos), l), \
             next = list_next_entry(pos, l);                    \
             &(nfp_prog)->insns != &pos->l &&                   \
             &(nfp_prog)->insns != &next->l;                    \
             pos = nfp_meta_next(pos),                          \
             next = nfp_meta_next(pos))

#define nfp_for_each_insn_walk3(nfp_prog, pos, next, next2)             \
        for (pos = list_first_entry(&(nfp_prog)->insns, typeof(*pos), l), \
             next = list_next_entry(pos, l),                    \
             next2 = list_next_entry(next, l);                  \
             &(nfp_prog)->insns != &pos->l &&                   \
             &(nfp_prog)->insns != &next->l &&                  \
             &(nfp_prog)->insns != &next2->l;                   \
             pos = nfp_meta_next(pos),                          \
             next = nfp_meta_next(pos),                         \
             next2 = nfp_meta_next(next))

static bool
nfp_meta_has_prev(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return meta->l.prev != &nfp_prog->insns;
}

static void nfp_prog_push(struct nfp_prog *nfp_prog, u64 insn)
{
        if (nfp_prog->__prog_alloc_len / sizeof(u64) == nfp_prog->prog_len) {
                pr_warn("instruction limit reached (%u NFP instructions)\n",
                        nfp_prog->prog_len);
                nfp_prog->error = -ENOSPC;
                return;
        }

        nfp_prog->prog[nfp_prog->prog_len] = insn;
        nfp_prog->prog_len++;
}

static unsigned int nfp_prog_current_offset(struct nfp_prog *nfp_prog)
{
        return nfp_prog->prog_len;
}

static bool
nfp_prog_confirm_current_offset(struct nfp_prog *nfp_prog, unsigned int off)
{
        /* If there is a recorded error we may have dropped instructions;
         * that doesn't have to be due to translator bug, and the translation
         * will fail anyway, so just return OK.
         */
        if (nfp_prog->error)
                return true;
        return !WARN_ON_ONCE(nfp_prog_current_offset(nfp_prog) != off);
}

/* --- Emitters --- */
static void
__emit_cmd(struct nfp_prog *nfp_prog, enum cmd_tgt_map op,
           u8 mode, u8 xfer, u8 areg, u8 breg, u8 size, enum cmd_ctx_swap ctx,
           bool indir)
{
        u64 insn;

        insn =  FIELD_PREP(OP_CMD_A_SRC, areg) |
                FIELD_PREP(OP_CMD_CTX, ctx) |
                FIELD_PREP(OP_CMD_B_SRC, breg) |
                FIELD_PREP(OP_CMD_TOKEN, cmd_tgt_act[op].token) |
                FIELD_PREP(OP_CMD_XFER, xfer) |
                FIELD_PREP(OP_CMD_CNT, size) |
                FIELD_PREP(OP_CMD_SIG, ctx != CMD_CTX_NO_SWAP) |
                FIELD_PREP(OP_CMD_TGT_CMD, cmd_tgt_act[op].tgt_cmd) |
                FIELD_PREP(OP_CMD_INDIR, indir) |
                FIELD_PREP(OP_CMD_MODE, mode);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_cmd_any(struct nfp_prog *nfp_prog, enum cmd_tgt_map op, u8 mode, u8 xfer,
             swreg lreg, swreg rreg, u8 size, enum cmd_ctx_swap ctx, bool indir)
{
        struct nfp_insn_re_regs reg;
        int err;

        err = swreg_to_restricted(reg_none(), lreg, rreg, &reg, false);
        if (err) {
                nfp_prog->error = err;
                return;
        }
        if (reg.swap) {
                pr_err("cmd can't swap arguments\n");
                nfp_prog->error = -EFAULT;
                return;
        }
        if (reg.dst_lmextn || reg.src_lmextn) {
                pr_err("cmd can't use LMextn\n");
                nfp_prog->error = -EFAULT;
                return;
        }

        __emit_cmd(nfp_prog, op, mode, xfer, reg.areg, reg.breg, size, ctx,
                   indir);
}

static void
emit_cmd(struct nfp_prog *nfp_prog, enum cmd_tgt_map op, u8 mode, u8 xfer,
         swreg lreg, swreg rreg, u8 size, enum cmd_ctx_swap ctx)
{
        emit_cmd_any(nfp_prog, op, mode, xfer, lreg, rreg, size, ctx, false);
}

static void
emit_cmd_indir(struct nfp_prog *nfp_prog, enum cmd_tgt_map op, u8 mode, u8 xfer,
               swreg lreg, swreg rreg, u8 size, enum cmd_ctx_swap ctx)
{
        emit_cmd_any(nfp_prog, op, mode, xfer, lreg, rreg, size, ctx, true);
}

static void
__emit_br(struct nfp_prog *nfp_prog, enum br_mask mask, enum br_ev_pip ev_pip,
          enum br_ctx_signal_state css, u16 addr, u8 defer)
{
        u16 addr_lo, addr_hi;
        u64 insn;

        addr_lo = addr & (OP_BR_ADDR_LO >> __bf_shf(OP_BR_ADDR_LO));
        addr_hi = addr != addr_lo;

        insn = OP_BR_BASE |
                FIELD_PREP(OP_BR_MASK, mask) |
                FIELD_PREP(OP_BR_EV_PIP, ev_pip) |
                FIELD_PREP(OP_BR_CSS, css) |
                FIELD_PREP(OP_BR_DEFBR, defer) |
                FIELD_PREP(OP_BR_ADDR_LO, addr_lo) |
                FIELD_PREP(OP_BR_ADDR_HI, addr_hi);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_br_relo(struct nfp_prog *nfp_prog, enum br_mask mask, u16 addr, u8 defer,
             enum nfp_relo_type relo)
{
        if (mask == BR_UNC && defer > 2) {
                pr_err("BUG: branch defer out of bounds %d\n", defer);
                nfp_prog->error = -EFAULT;
                return;
        }

        __emit_br(nfp_prog, mask,
                  mask != BR_UNC ? BR_EV_PIP_COND : BR_EV_PIP_UNCOND,
                  BR_CSS_NONE, addr, defer);

        nfp_prog->prog[nfp_prog->prog_len - 1] |=
                FIELD_PREP(OP_RELO_TYPE, relo);
}

static void
emit_br(struct nfp_prog *nfp_prog, enum br_mask mask, u16 addr, u8 defer)
{
        emit_br_relo(nfp_prog, mask, addr, defer, RELO_BR_REL);
}

static void
__emit_br_bit(struct nfp_prog *nfp_prog, u16 areg, u16 breg, u16 addr, u8 defer,
              bool set, bool src_lmextn)
{
        u16 addr_lo, addr_hi;
        u64 insn;

        addr_lo = addr & (OP_BR_BIT_ADDR_LO >> __bf_shf(OP_BR_BIT_ADDR_LO));
        addr_hi = addr != addr_lo;

        insn = OP_BR_BIT_BASE |
                FIELD_PREP(OP_BR_BIT_A_SRC, areg) |
                FIELD_PREP(OP_BR_BIT_B_SRC, breg) |
                FIELD_PREP(OP_BR_BIT_BV, set) |
                FIELD_PREP(OP_BR_BIT_DEFBR, defer) |
                FIELD_PREP(OP_BR_BIT_ADDR_LO, addr_lo) |
                FIELD_PREP(OP_BR_BIT_ADDR_HI, addr_hi) |
                FIELD_PREP(OP_BR_BIT_SRC_LMEXTN, src_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_br_bit_relo(struct nfp_prog *nfp_prog, swreg src, u8 bit, u16 addr,
                 u8 defer, bool set, enum nfp_relo_type relo)
{
        struct nfp_insn_re_regs reg;
        int err;

        /* NOTE: The bit to test is specified as an rotation amount, such that
         *       the bit to test will be placed on the MSB of the result when
         *       doing a rotate right. For bit X, we need right rotate X + 1.
         */
        bit += 1;

        err = swreg_to_restricted(reg_none(), src, reg_imm(bit), &reg, false);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_br_bit(nfp_prog, reg.areg, reg.breg, addr, defer, set,
                      reg.src_lmextn);

        nfp_prog->prog[nfp_prog->prog_len - 1] |=
                FIELD_PREP(OP_RELO_TYPE, relo);
}

static void
emit_br_bset(struct nfp_prog *nfp_prog, swreg src, u8 bit, u16 addr, u8 defer)
{
        emit_br_bit_relo(nfp_prog, src, bit, addr, defer, true, RELO_BR_REL);
}

static void
__emit_br_alu(struct nfp_prog *nfp_prog, u16 areg, u16 breg, u16 imm_hi,
              u8 defer, bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_BR_ALU_BASE |
                FIELD_PREP(OP_BR_ALU_A_SRC, areg) |
                FIELD_PREP(OP_BR_ALU_B_SRC, breg) |
                FIELD_PREP(OP_BR_ALU_DEFBR, defer) |
                FIELD_PREP(OP_BR_ALU_IMM_HI, imm_hi) |
                FIELD_PREP(OP_BR_ALU_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_BR_ALU_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void emit_rtn(struct nfp_prog *nfp_prog, swreg base, u8 defer)
{
        struct nfp_insn_ur_regs reg;
        int err;

        err = swreg_to_unrestricted(reg_none(), base, reg_imm(0), &reg);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_br_alu(nfp_prog, reg.areg, reg.breg, 0, defer, reg.dst_lmextn,
                      reg.src_lmextn);
}

static void
__emit_immed(struct nfp_prog *nfp_prog, u16 areg, u16 breg, u16 imm_hi,
             enum immed_width width, bool invert,
             enum immed_shift shift, bool wr_both,
             bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_IMMED_BASE |
                FIELD_PREP(OP_IMMED_A_SRC, areg) |
                FIELD_PREP(OP_IMMED_B_SRC, breg) |
                FIELD_PREP(OP_IMMED_IMM, imm_hi) |
                FIELD_PREP(OP_IMMED_WIDTH, width) |
                FIELD_PREP(OP_IMMED_INV, invert) |
                FIELD_PREP(OP_IMMED_SHIFT, shift) |
                FIELD_PREP(OP_IMMED_WR_AB, wr_both) |
                FIELD_PREP(OP_IMMED_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_IMMED_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_immed(struct nfp_prog *nfp_prog, swreg dst, u16 imm,
           enum immed_width width, bool invert, enum immed_shift shift)
{
        struct nfp_insn_ur_regs reg;
        int err;

        if (swreg_type(dst) == NN_REG_IMM) {
                nfp_prog->error = -EFAULT;
                return;
        }

        err = swreg_to_unrestricted(dst, dst, reg_imm(imm & 0xff), &reg);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        /* Use reg.dst when destination is No-Dest. */
        __emit_immed(nfp_prog,
                     swreg_type(dst) == NN_REG_NONE ? reg.dst : reg.areg,
                     reg.breg, imm >> 8, width, invert, shift,
                     reg.wr_both, reg.dst_lmextn, reg.src_lmextn);
}

static void
__emit_shf(struct nfp_prog *nfp_prog, u16 dst, enum alu_dst_ab dst_ab,
           enum shf_sc sc, u8 shift,
           u16 areg, enum shf_op op, u16 breg, bool i8, bool sw, bool wr_both,
           bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        if (!FIELD_FIT(OP_SHF_SHIFT, shift)) {
                nfp_prog->error = -EFAULT;
                return;
        }

        /* NFP shift instruction has something special. If shift direction is
         * left then shift amount of 1 to 31 is specified as 32 minus the amount
         * to shift.
         *
         * But no need to do this for indirect shift which has shift amount be
         * 0. Even after we do this subtraction, shift amount 0 will be turned
         * into 32 which will eventually be encoded the same as 0 because only
         * low 5 bits are encoded, but shift amount be 32 will fail the
         * FIELD_PREP check done later on shift mask (0x1f), due to 32 is out of
         * mask range.
         */
        if (sc == SHF_SC_L_SHF && shift)
                shift = 32 - shift;

        insn = OP_SHF_BASE |
                FIELD_PREP(OP_SHF_A_SRC, areg) |
                FIELD_PREP(OP_SHF_SC, sc) |
                FIELD_PREP(OP_SHF_B_SRC, breg) |
                FIELD_PREP(OP_SHF_I8, i8) |
                FIELD_PREP(OP_SHF_SW, sw) |
                FIELD_PREP(OP_SHF_DST, dst) |
                FIELD_PREP(OP_SHF_SHIFT, shift) |
                FIELD_PREP(OP_SHF_OP, op) |
                FIELD_PREP(OP_SHF_DST_AB, dst_ab) |
                FIELD_PREP(OP_SHF_WR_AB, wr_both) |
                FIELD_PREP(OP_SHF_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_SHF_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_shf(struct nfp_prog *nfp_prog, swreg dst,
         swreg lreg, enum shf_op op, swreg rreg, enum shf_sc sc, u8 shift)
{
        struct nfp_insn_re_regs reg;
        int err;

        err = swreg_to_restricted(dst, lreg, rreg, &reg, true);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_shf(nfp_prog, reg.dst, reg.dst_ab, sc, shift,
                   reg.areg, op, reg.breg, reg.i8, reg.swap, reg.wr_both,
                   reg.dst_lmextn, reg.src_lmextn);
}

static void
emit_shf_indir(struct nfp_prog *nfp_prog, swreg dst,
               swreg lreg, enum shf_op op, swreg rreg, enum shf_sc sc)
{
        if (sc == SHF_SC_R_ROT) {
                pr_err("indirect shift is not allowed on rotation\n");
                nfp_prog->error = -EFAULT;
                return;
        }

        emit_shf(nfp_prog, dst, lreg, op, rreg, sc, 0);
}

static void
__emit_alu(struct nfp_prog *nfp_prog, u16 dst, enum alu_dst_ab dst_ab,
           u16 areg, enum alu_op op, u16 breg, bool swap, bool wr_both,
           bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_ALU_BASE |
                FIELD_PREP(OP_ALU_A_SRC, areg) |
                FIELD_PREP(OP_ALU_B_SRC, breg) |
                FIELD_PREP(OP_ALU_DST, dst) |
                FIELD_PREP(OP_ALU_SW, swap) |
                FIELD_PREP(OP_ALU_OP, op) |
                FIELD_PREP(OP_ALU_DST_AB, dst_ab) |
                FIELD_PREP(OP_ALU_WR_AB, wr_both) |
                FIELD_PREP(OP_ALU_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_ALU_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_alu(struct nfp_prog *nfp_prog, swreg dst,
         swreg lreg, enum alu_op op, swreg rreg)
{
        struct nfp_insn_ur_regs reg;
        int err;

        err = swreg_to_unrestricted(dst, lreg, rreg, &reg);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_alu(nfp_prog, reg.dst, reg.dst_ab,
                   reg.areg, op, reg.breg, reg.swap, reg.wr_both,
                   reg.dst_lmextn, reg.src_lmextn);
}

static void
__emit_mul(struct nfp_prog *nfp_prog, enum alu_dst_ab dst_ab, u16 areg,
           enum mul_type type, enum mul_step step, u16 breg, bool swap,
           bool wr_both, bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_MUL_BASE |
                FIELD_PREP(OP_MUL_A_SRC, areg) |
                FIELD_PREP(OP_MUL_B_SRC, breg) |
                FIELD_PREP(OP_MUL_STEP, step) |
                FIELD_PREP(OP_MUL_DST_AB, dst_ab) |
                FIELD_PREP(OP_MUL_SW, swap) |
                FIELD_PREP(OP_MUL_TYPE, type) |
                FIELD_PREP(OP_MUL_WR_AB, wr_both) |
                FIELD_PREP(OP_MUL_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_MUL_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_mul(struct nfp_prog *nfp_prog, swreg lreg, enum mul_type type,
         enum mul_step step, swreg rreg)
{
        struct nfp_insn_ur_regs reg;
        u16 areg;
        int err;

        if (type == MUL_TYPE_START && step != MUL_STEP_NONE) {
                nfp_prog->error = -EINVAL;
                return;
        }

        if (step == MUL_LAST || step == MUL_LAST_2) {
                /* When type is step and step Number is LAST or LAST2, left
                 * source is used as destination.
                 */
                err = swreg_to_unrestricted(lreg, reg_none(), rreg, &reg);
                areg = reg.dst;
        } else {
                err = swreg_to_unrestricted(reg_none(), lreg, rreg, &reg);
                areg = reg.areg;
        }

        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_mul(nfp_prog, reg.dst_ab, areg, type, step, reg.breg, reg.swap,
                   reg.wr_both, reg.dst_lmextn, reg.src_lmextn);
}

static void
__emit_ld_field(struct nfp_prog *nfp_prog, enum shf_sc sc,
                u8 areg, u8 bmask, u8 breg, u8 shift, bool imm8,
                bool zero, bool swap, bool wr_both,
                bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_LDF_BASE |
                FIELD_PREP(OP_LDF_A_SRC, areg) |
                FIELD_PREP(OP_LDF_SC, sc) |
                FIELD_PREP(OP_LDF_B_SRC, breg) |
                FIELD_PREP(OP_LDF_I8, imm8) |
                FIELD_PREP(OP_LDF_SW, swap) |
                FIELD_PREP(OP_LDF_ZF, zero) |
                FIELD_PREP(OP_LDF_BMASK, bmask) |
                FIELD_PREP(OP_LDF_SHF, shift) |
                FIELD_PREP(OP_LDF_WR_AB, wr_both) |
                FIELD_PREP(OP_LDF_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_LDF_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void
emit_ld_field_any(struct nfp_prog *nfp_prog, swreg dst, u8 bmask, swreg src,
                  enum shf_sc sc, u8 shift, bool zero)
{
        struct nfp_insn_re_regs reg;
        int err;

        /* Note: ld_field is special as it uses one of the src regs as dst */
        err = swreg_to_restricted(dst, dst, src, &reg, true);
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_ld_field(nfp_prog, sc, reg.areg, bmask, reg.breg, shift,
                        reg.i8, zero, reg.swap, reg.wr_both,
                        reg.dst_lmextn, reg.src_lmextn);
}

static void
emit_ld_field(struct nfp_prog *nfp_prog, swreg dst, u8 bmask, swreg src,
              enum shf_sc sc, u8 shift)
{
        emit_ld_field_any(nfp_prog, dst, bmask, src, sc, shift, false);
}

static void
__emit_lcsr(struct nfp_prog *nfp_prog, u16 areg, u16 breg, bool wr, u16 addr,
            bool dst_lmextn, bool src_lmextn)
{
        u64 insn;

        insn = OP_LCSR_BASE |
                FIELD_PREP(OP_LCSR_A_SRC, areg) |
                FIELD_PREP(OP_LCSR_B_SRC, breg) |
                FIELD_PREP(OP_LCSR_WRITE, wr) |
                FIELD_PREP(OP_LCSR_ADDR, addr / 4) |
                FIELD_PREP(OP_LCSR_SRC_LMEXTN, src_lmextn) |
                FIELD_PREP(OP_LCSR_DST_LMEXTN, dst_lmextn);

        nfp_prog_push(nfp_prog, insn);
}

static void emit_csr_wr(struct nfp_prog *nfp_prog, swreg src, u16 addr)
{
        struct nfp_insn_ur_regs reg;
        int err;

        /* This instruction takes immeds instead of reg_none() for the ignored
         * operand, but we can't encode 2 immeds in one instr with our normal
         * swreg infra so if param is an immed, we encode as reg_none() and
         * copy the immed to both operands.
         */
        if (swreg_type(src) == NN_REG_IMM) {
                err = swreg_to_unrestricted(reg_none(), src, reg_none(), &reg);
                reg.breg = reg.areg;
        } else {
                err = swreg_to_unrestricted(reg_none(), src, reg_imm(0), &reg);
        }
        if (err) {
                nfp_prog->error = err;
                return;
        }

        __emit_lcsr(nfp_prog, reg.areg, reg.breg, true, addr,
                    false, reg.src_lmextn);
}

/* CSR value is read in following immed[gpr, 0] */
static void __emit_csr_rd(struct nfp_prog *nfp_prog, u16 addr)
{
        __emit_lcsr(nfp_prog, 0, 0, false, addr, false, false);
}

static void emit_nop(struct nfp_prog *nfp_prog)
{
        __emit_immed(nfp_prog, UR_REG_IMM, UR_REG_IMM, 0, 0, 0, 0, 0, 0, 0);
}

/* --- Wrappers --- */
static bool pack_immed(u32 imm, u16 *val, enum immed_shift *shift)
{
        if (!(imm & 0xffff0000)) {
                *val = imm;
                *shift = IMMED_SHIFT_0B;
        } else if (!(imm & 0xff0000ff)) {
                *val = imm >> 8;
                *shift = IMMED_SHIFT_1B;
        } else if (!(imm & 0x0000ffff)) {
                *val = imm >> 16;
                *shift = IMMED_SHIFT_2B;
        } else {
                return false;
        }

        return true;
}

static void wrp_immed(struct nfp_prog *nfp_prog, swreg dst, u32 imm)
{
        enum immed_shift shift;
        u16 val;

        if (pack_immed(imm, &val, &shift)) {
                emit_immed(nfp_prog, dst, val, IMMED_WIDTH_ALL, false, shift);
        } else if (pack_immed(~imm, &val, &shift)) {
                emit_immed(nfp_prog, dst, val, IMMED_WIDTH_ALL, true, shift);
        } else {
                emit_immed(nfp_prog, dst, imm & 0xffff, IMMED_WIDTH_ALL,
                           false, IMMED_SHIFT_0B);
                emit_immed(nfp_prog, dst, imm >> 16, IMMED_WIDTH_WORD,
                           false, IMMED_SHIFT_2B);
        }
}

static void
wrp_zext(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, u8 dst)
{
        if (meta->flags & FLAG_INSN_DO_ZEXT)
                wrp_immed(nfp_prog, reg_both(dst + 1), 0);
}

static void
wrp_immed_relo(struct nfp_prog *nfp_prog, swreg dst, u32 imm,
               enum nfp_relo_type relo)
{
        if (imm > 0xffff) {
                pr_err("relocation of a large immediate!\n");
                nfp_prog->error = -EFAULT;
                return;
        }
        emit_immed(nfp_prog, dst, imm, IMMED_WIDTH_ALL, false, IMMED_SHIFT_0B);

        nfp_prog->prog[nfp_prog->prog_len - 1] |=
                FIELD_PREP(OP_RELO_TYPE, relo);
}

/* ur_load_imm_any() - encode immediate or use tmp register (unrestricted)
 * If the @imm is small enough encode it directly in operand and return
 * otherwise load @imm to a spare register and return its encoding.
 */
static swreg ur_load_imm_any(struct nfp_prog *nfp_prog, u32 imm, swreg tmp_reg)
{
        if (FIELD_FIT(UR_REG_IMM_MAX, imm))
                return reg_imm(imm);

        wrp_immed(nfp_prog, tmp_reg, imm);
        return tmp_reg;
}

/* re_load_imm_any() - encode immediate or use tmp register (restricted)
 * If the @imm is small enough encode it directly in operand and return
 * otherwise load @imm to a spare register and return its encoding.
 */
static swreg re_load_imm_any(struct nfp_prog *nfp_prog, u32 imm, swreg tmp_reg)
{
        if (FIELD_FIT(RE_REG_IMM_MAX, imm))
                return reg_imm(imm);

        wrp_immed(nfp_prog, tmp_reg, imm);
        return tmp_reg;
}

static void wrp_nops(struct nfp_prog *nfp_prog, unsigned int count)
{
        while (count--)
                emit_nop(nfp_prog);
}

static void wrp_mov(struct nfp_prog *nfp_prog, swreg dst, swreg src)
{
        emit_alu(nfp_prog, dst, reg_none(), ALU_OP_NONE, src);
}

static void wrp_reg_mov(struct nfp_prog *nfp_prog, u16 dst, u16 src)
{
        wrp_mov(nfp_prog, reg_both(dst), reg_b(src));
}

/* wrp_reg_subpart() - load @field_len bytes from @offset of @src, write the
 * result to @dst from low end.
 */
static void
wrp_reg_subpart(struct nfp_prog *nfp_prog, swreg dst, swreg src, u8 field_len,
                u8 offset)
{
        enum shf_sc sc = offset ? SHF_SC_R_SHF : SHF_SC_NONE;
        u8 mask = (1 << field_len) - 1;

        emit_ld_field_any(nfp_prog, dst, mask, src, sc, offset * 8, true);
}

/* wrp_reg_or_subpart() - load @field_len bytes from low end of @src, or the
 * result to @dst from offset, there is no change on the other bits of @dst.
 */
static void
wrp_reg_or_subpart(struct nfp_prog *nfp_prog, swreg dst, swreg src,
                   u8 field_len, u8 offset)
{
        enum shf_sc sc = offset ? SHF_SC_L_SHF : SHF_SC_NONE;
        u8 mask = ((1 << field_len) - 1) << offset;

        emit_ld_field(nfp_prog, dst, mask, src, sc, 32 - offset * 8);
}

static void
addr40_offset(struct nfp_prog *nfp_prog, u8 src_gpr, swreg offset,
              swreg *rega, swreg *regb)
{
        if (offset == reg_imm(0)) {
                *rega = reg_a(src_gpr);
                *regb = reg_b(src_gpr + 1);
                return;
        }

        emit_alu(nfp_prog, imm_a(nfp_prog), reg_a(src_gpr), ALU_OP_ADD, offset);
        emit_alu(nfp_prog, imm_b(nfp_prog), reg_b(src_gpr + 1), ALU_OP_ADD_C,
                 reg_imm(0));
        *rega = imm_a(nfp_prog);
        *regb = imm_b(nfp_prog);
}

/* NFP has Command Push Pull bus which supports bluk memory operations. */
static int nfp_cpp_memcpy(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        bool descending_seq = meta->ldst_gather_len < 0;
        s16 len = abs(meta->ldst_gather_len);
        swreg src_base, off;
        bool src_40bit_addr;
        unsigned int i;
        u8 xfer_num;

        off = re_load_imm_any(nfp_prog, meta->insn.off, imm_b(nfp_prog));
        src_40bit_addr = meta->ptr.type == PTR_TO_MAP_VALUE;
        src_base = reg_a(meta->insn.src_reg * 2);
        xfer_num = round_up(len, 4) / 4;

        if (src_40bit_addr)
                addr40_offset(nfp_prog, meta->insn.src_reg * 2, off, &src_base,
                              &off);

        /* Setup PREV_ALU fields to override memory read length. */
        if (len > 32)
                wrp_immed(nfp_prog, reg_none(),
                          CMD_OVE_LEN | FIELD_PREP(CMD_OV_LEN, xfer_num - 1));

        /* Memory read from source addr into transfer-in registers. */
        emit_cmd_any(nfp_prog, CMD_TGT_READ32_SWAP,
                     src_40bit_addr ? CMD_MODE_40b_BA : CMD_MODE_32b, 0,
                     src_base, off, xfer_num - 1, CMD_CTX_SWAP, len > 32);

        /* Move from transfer-in to transfer-out. */
        for (i = 0; i < xfer_num; i++)
                wrp_mov(nfp_prog, reg_xfer(i), reg_xfer(i));

        off = re_load_imm_any(nfp_prog, meta->paired_st->off, imm_b(nfp_prog));

        if (len <= 8) {
                /* Use single direct_ref write8. */
                emit_cmd(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b, 0,
                         reg_a(meta->paired_st->dst_reg * 2), off, len - 1,
                         CMD_CTX_SWAP);
        } else if (len <= 32 && IS_ALIGNED(len, 4)) {
                /* Use single direct_ref write32. */
                emit_cmd(nfp_prog, CMD_TGT_WRITE32_SWAP, CMD_MODE_32b, 0,
                         reg_a(meta->paired_st->dst_reg * 2), off, xfer_num - 1,
                         CMD_CTX_SWAP);
        } else if (len <= 32) {
                /* Use single indirect_ref write8. */
                wrp_immed(nfp_prog, reg_none(),
                          CMD_OVE_LEN | FIELD_PREP(CMD_OV_LEN, len - 1));
                emit_cmd_indir(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b, 0,
                               reg_a(meta->paired_st->dst_reg * 2), off,
                               len - 1, CMD_CTX_SWAP);
        } else if (IS_ALIGNED(len, 4)) {
                /* Use single indirect_ref write32. */
                wrp_immed(nfp_prog, reg_none(),
                          CMD_OVE_LEN | FIELD_PREP(CMD_OV_LEN, xfer_num - 1));
                emit_cmd_indir(nfp_prog, CMD_TGT_WRITE32_SWAP, CMD_MODE_32b, 0,
                               reg_a(meta->paired_st->dst_reg * 2), off,
                               xfer_num - 1, CMD_CTX_SWAP);
        } else if (len <= 40) {
                /* Use one direct_ref write32 to write the first 32-bytes, then
                 * another direct_ref write8 to write the remaining bytes.
                 */
                emit_cmd(nfp_prog, CMD_TGT_WRITE32_SWAP, CMD_MODE_32b, 0,
                         reg_a(meta->paired_st->dst_reg * 2), off, 7,
                         CMD_CTX_SWAP);

                off = re_load_imm_any(nfp_prog, meta->paired_st->off + 32,
                                      imm_b(nfp_prog));
                emit_cmd(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b, 8,
                         reg_a(meta->paired_st->dst_reg * 2), off, len - 33,
                         CMD_CTX_SWAP);
        } else {
                /* Use one indirect_ref write32 to write 4-bytes aligned length,
                 * then another direct_ref write8 to write the remaining bytes.
                 */
                u8 new_off;

                wrp_immed(nfp_prog, reg_none(),
                          CMD_OVE_LEN | FIELD_PREP(CMD_OV_LEN, xfer_num - 2));
                emit_cmd_indir(nfp_prog, CMD_TGT_WRITE32_SWAP, CMD_MODE_32b, 0,
                               reg_a(meta->paired_st->dst_reg * 2), off,
                               xfer_num - 2, CMD_CTX_SWAP);
                new_off = meta->paired_st->off + (xfer_num - 1) * 4;
                off = re_load_imm_any(nfp_prog, new_off, imm_b(nfp_prog));
                emit_cmd(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b,
                         xfer_num - 1, reg_a(meta->paired_st->dst_reg * 2), off,
                         (len & 0x3) - 1, CMD_CTX_SWAP);
        }

        /* TODO: The following extra load is to make sure data flow be identical
         *  before and after we do memory copy optimization.
         *
         *  The load destination register is not guaranteed to be dead, so we
         *  need to make sure it is loaded with the value the same as before
         *  this transformation.
         *
         *  These extra loads could be removed once we have accurate register
         *  usage information.
         */
        if (descending_seq)
                xfer_num = 0;
        else if (BPF_SIZE(meta->insn.code) != BPF_DW)
                xfer_num = xfer_num - 1;
        else
                xfer_num = xfer_num - 2;

        switch (BPF_SIZE(meta->insn.code)) {
        case BPF_B:
                wrp_reg_subpart(nfp_prog, reg_both(meta->insn.dst_reg * 2),
                                reg_xfer(xfer_num), 1,
                                IS_ALIGNED(len, 4) ? 3 : (len & 3) - 1);
                break;
        case BPF_H:
                wrp_reg_subpart(nfp_prog, reg_both(meta->insn.dst_reg * 2),
                                reg_xfer(xfer_num), 2, (len & 3) ^ 2);
                break;
        case BPF_W:
                wrp_mov(nfp_prog, reg_both(meta->insn.dst_reg * 2),
                        reg_xfer(0));
                break;
        case BPF_DW:
                wrp_mov(nfp_prog, reg_both(meta->insn.dst_reg * 2),
                        reg_xfer(xfer_num));
                wrp_mov(nfp_prog, reg_both(meta->insn.dst_reg * 2 + 1),
                        reg_xfer(xfer_num + 1));
                break;
        }

        if (BPF_SIZE(meta->insn.code) != BPF_DW)
                wrp_immed(nfp_prog, reg_both(meta->insn.dst_reg * 2 + 1), 0);

        return 0;
}

static int
data_ld(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, swreg offset,
        u8 dst_gpr, int size)
{
        unsigned int i;
        u16 shift, sz;

        /* We load the value from the address indicated in @offset and then
         * shift out the data we don't need.  Note: this is big endian!
         */
        sz = max(size, 4);
        shift = size < 4 ? 4 - size : 0;

        emit_cmd(nfp_prog, CMD_TGT_READ8, CMD_MODE_32b, 0,
                 pptr_reg(nfp_prog), offset, sz - 1, CMD_CTX_SWAP);

        i = 0;
        if (shift)
                emit_shf(nfp_prog, reg_both(dst_gpr), reg_none(), SHF_OP_NONE,
                         reg_xfer(0), SHF_SC_R_SHF, shift * 8);
        else
                for (; i * 4 < size; i++)
                        wrp_mov(nfp_prog, reg_both(dst_gpr + i), reg_xfer(i));

        if (i < 2)
                wrp_zext(nfp_prog, meta, dst_gpr);

        return 0;
}

static int
data_ld_host_order(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                   u8 dst_gpr, swreg lreg, swreg rreg, int size,
                   enum cmd_mode mode)
{
        unsigned int i;
        u8 mask, sz;

        /* We load the value from the address indicated in rreg + lreg and then
         * mask out the data we don't need.  Note: this is little endian!
         */
        sz = max(size, 4);
        mask = size < 4 ? GENMASK(size - 1, 0) : 0;

        emit_cmd(nfp_prog, CMD_TGT_READ32_SWAP, mode, 0,
                 lreg, rreg, sz / 4 - 1, CMD_CTX_SWAP);

        i = 0;
        if (mask)
                emit_ld_field_any(nfp_prog, reg_both(dst_gpr), mask,
                                  reg_xfer(0), SHF_SC_NONE, 0, true);
        else
                for (; i * 4 < size; i++)
                        wrp_mov(nfp_prog, reg_both(dst_gpr + i), reg_xfer(i));

        if (i < 2)
                wrp_zext(nfp_prog, meta, dst_gpr);

        return 0;
}

static int
data_ld_host_order_addr32(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                          u8 src_gpr, swreg offset, u8 dst_gpr, u8 size)
{
        return data_ld_host_order(nfp_prog, meta, dst_gpr, reg_a(src_gpr),
                                  offset, size, CMD_MODE_32b);
}

static int
data_ld_host_order_addr40(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                          u8 src_gpr, swreg offset, u8 dst_gpr, u8 size)
{
        swreg rega, regb;

        addr40_offset(nfp_prog, src_gpr, offset, &rega, &regb);

        return data_ld_host_order(nfp_prog, meta, dst_gpr, rega, regb,
                                  size, CMD_MODE_40b_BA);
}

static int
construct_data_ind_ld(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                      u16 offset, u16 src, u8 size)
{
        swreg tmp_reg;

        /* Calculate the true offset (src_reg + imm) */
        tmp_reg = ur_load_imm_any(nfp_prog, offset, imm_b(nfp_prog));
        emit_alu(nfp_prog, imm_both(nfp_prog), reg_a(src), ALU_OP_ADD, tmp_reg);

        /* Check packet length (size guaranteed to fit b/c it's u8) */
        emit_alu(nfp_prog, imm_a(nfp_prog),
                 imm_a(nfp_prog), ALU_OP_ADD, reg_imm(size));
        emit_alu(nfp_prog, reg_none(),
                 plen_reg(nfp_prog), ALU_OP_SUB, imm_a(nfp_prog));
        emit_br_relo(nfp_prog, BR_BLO, BR_OFF_RELO, 0, RELO_BR_GO_ABORT);

        /* Load data */
        return data_ld(nfp_prog, meta, imm_b(nfp_prog), 0, size);
}

static int
construct_data_ld(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                  u16 offset, u8 size)
{
        swreg tmp_reg;

        /* Check packet length */
        tmp_reg = ur_load_imm_any(nfp_prog, offset + size, imm_a(nfp_prog));
        emit_alu(nfp_prog, reg_none(), plen_reg(nfp_prog), ALU_OP_SUB, tmp_reg);
        emit_br_relo(nfp_prog, BR_BLO, BR_OFF_RELO, 0, RELO_BR_GO_ABORT);

        /* Load data */
        tmp_reg = re_load_imm_any(nfp_prog, offset, imm_b(nfp_prog));
        return data_ld(nfp_prog, meta, tmp_reg, 0, size);
}

static int
data_stx_host_order(struct nfp_prog *nfp_prog, u8 dst_gpr, swreg offset,
                    u8 src_gpr, u8 size)
{
        unsigned int i;

        for (i = 0; i * 4 < size; i++)
                wrp_mov(nfp_prog, reg_xfer(i), reg_a(src_gpr + i));

        emit_cmd(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b, 0,
                 reg_a(dst_gpr), offset, size - 1, CMD_CTX_SWAP);

        return 0;
}

static int

data_st_host_order(struct nfp_prog *nfp_prog, u8 dst_gpr, swreg offset,
                   u64 imm, u8 size)
{
        wrp_immed(nfp_prog, reg_xfer(0), imm);
        if (size == 8)
                wrp_immed(nfp_prog, reg_xfer(1), imm >> 32);

        emit_cmd(nfp_prog, CMD_TGT_WRITE8_SWAP, CMD_MODE_32b, 0,
                 reg_a(dst_gpr), offset, size - 1, CMD_CTX_SWAP);

        return 0;
}

typedef int
(*lmem_step)(struct nfp_prog *nfp_prog, u8 gpr, u8 gpr_byte, s32 off,
             unsigned int size, bool first, bool new_gpr, bool last, bool lm3,
             bool needs_inc);

static int
wrp_lmem_load(struct nfp_prog *nfp_prog, u8 dst, u8 dst_byte, s32 off,
              unsigned int size, bool first, bool new_gpr, bool last, bool lm3,
              bool needs_inc)
{
        bool should_inc = needs_inc && new_gpr && !last;
        u32 idx, src_byte;
        enum shf_sc sc;
        swreg reg;
        int shf;
        u8 mask;

        if (WARN_ON_ONCE(dst_byte + size > 4 || off % 4 + size > 4))
                return -EOPNOTSUPP;

        idx = off / 4;

        /* Move the entire word */
        if (size == 4) {
                wrp_mov(nfp_prog, reg_both(dst),
                        should_inc ? reg_lm_inc(3) : reg_lm(lm3 ? 3 : 0, idx));
                return 0;
        }

        if (WARN_ON_ONCE(lm3 && idx > RE_REG_LM_IDX_MAX))
                return -EOPNOTSUPP;

        src_byte = off % 4;

        mask = (1 << size) - 1;
        mask <<= dst_byte;

        if (WARN_ON_ONCE(mask > 0xf))
                return -EOPNOTSUPP;

        shf = abs(src_byte - dst_byte) * 8;
        if (src_byte == dst_byte) {
                sc = SHF_SC_NONE;
        } else if (src_byte < dst_byte) {
                shf = 32 - shf;
                sc = SHF_SC_L_SHF;
        } else {
                sc = SHF_SC_R_SHF;
        }

        /* ld_field can address fewer indexes, if offset too large do RMW.
         * Because we RMV twice we waste 2 cycles on unaligned 8 byte writes.
         */
        if (idx <= RE_REG_LM_IDX_MAX) {
                reg = reg_lm(lm3 ? 3 : 0, idx);
        } else {
                reg = imm_a(nfp_prog);
                /* If it's not the first part of the load and we start a new GPR
                 * that means we are loading a second part of the LMEM word into
                 * a new GPR.  IOW we've already looked that LMEM word and
                 * therefore it has been loaded into imm_a().
                 */
                if (first || !new_gpr)
                        wrp_mov(nfp_prog, reg, reg_lm(0, idx));
        }

        emit_ld_field_any(nfp_prog, reg_both(dst), mask, reg, sc, shf, new_gpr);

        if (should_inc)
                wrp_mov(nfp_prog, reg_none(), reg_lm_inc(3));

        return 0;
}

static int
wrp_lmem_store(struct nfp_prog *nfp_prog, u8 src, u8 src_byte, s32 off,
               unsigned int size, bool first, bool new_gpr, bool last, bool lm3,
               bool needs_inc)
{
        bool should_inc = needs_inc && new_gpr && !last;
        u32 idx, dst_byte;
        enum shf_sc sc;
        swreg reg;
        int shf;
        u8 mask;

        if (WARN_ON_ONCE(src_byte + size > 4 || off % 4 + size > 4))
                return -EOPNOTSUPP;

        idx = off / 4;

        /* Move the entire word */
        if (size == 4) {
                wrp_mov(nfp_prog,
                        should_inc ? reg_lm_inc(3) : reg_lm(lm3 ? 3 : 0, idx),
                        reg_b(src));
                return 0;
        }

        if (WARN_ON_ONCE(lm3 && idx > RE_REG_LM_IDX_MAX))
                return -EOPNOTSUPP;

        dst_byte = off % 4;

        mask = (1 << size) - 1;
        mask <<= dst_byte;

        if (WARN_ON_ONCE(mask > 0xf))
                return -EOPNOTSUPP;

        shf = abs(src_byte - dst_byte) * 8;
        if (src_byte == dst_byte) {
                sc = SHF_SC_NONE;
        } else if (src_byte < dst_byte) {
                shf = 32 - shf;
                sc = SHF_SC_L_SHF;
        } else {
                sc = SHF_SC_R_SHF;
        }

        /* ld_field can address fewer indexes, if offset too large do RMW.
         * Because we RMV twice we waste 2 cycles on unaligned 8 byte writes.
         */
        if (idx <= RE_REG_LM_IDX_MAX) {
                reg = reg_lm(lm3 ? 3 : 0, idx);
        } else {
                reg = imm_a(nfp_prog);
                /* Only first and last LMEM locations are going to need RMW,
                 * the middle location will be overwritten fully.
                 */
                if (first || last)
                        wrp_mov(nfp_prog, reg, reg_lm(0, idx));
        }

        emit_ld_field(nfp_prog, reg, mask, reg_b(src), sc, shf);

        if (new_gpr || last) {
                if (idx > RE_REG_LM_IDX_MAX)
                        wrp_mov(nfp_prog, reg_lm(0, idx), reg);
                if (should_inc)
                        wrp_mov(nfp_prog, reg_none(), reg_lm_inc(3));
        }

        return 0;
}

static int
mem_op_stack(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
             unsigned int size, unsigned int ptr_off, u8 gpr, u8 ptr_gpr,
             bool clr_gpr, lmem_step step)
{
        s32 off = nfp_prog->stack_frame_depth + meta->insn.off + ptr_off;
        bool first = true, narrow_ld, last;
        bool needs_inc = false;
        swreg stack_off_reg;
        u8 prev_gpr = 255;
        u32 gpr_byte = 0;
        bool lm3 = true;
        int ret;

        if (meta->ptr_not_const ||
            meta->flags & FLAG_INSN_PTR_CALLER_STACK_FRAME) {
                /* Use of the last encountered ptr_off is OK, they all have
                 * the same alignment.  Depend on low bits of value being
                 * discarded when written to LMaddr register.
                 */
                stack_off_reg = ur_load_imm_any(nfp_prog, meta->insn.off,
                                                stack_imm(nfp_prog));

                emit_alu(nfp_prog, imm_b(nfp_prog),
                         reg_a(ptr_gpr), ALU_OP_ADD, stack_off_reg);

                needs_inc = true;
        } else if (off + size <= 64) {
                /* We can reach bottom 64B with LMaddr0 */
                lm3 = false;
        } else if (round_down(off, 32) == round_down(off + size - 1, 32)) {
                /* We have to set up a new pointer.  If we know the offset
                 * and the entire access falls into a single 32 byte aligned
                 * window we won't have to increment the LM pointer.
                 * The 32 byte alignment is imporant because offset is ORed in
                 * not added when doing *l$indexN[off].
                 */
                stack_off_reg = ur_load_imm_any(nfp_prog, round_down(off, 32),
                                                stack_imm(nfp_prog));
                emit_alu(nfp_prog, imm_b(nfp_prog),
                         stack_reg(nfp_prog), ALU_OP_ADD, stack_off_reg);

                off %= 32;
        } else {
                stack_off_reg = ur_load_imm_any(nfp_prog, round_down(off, 4),
                                                stack_imm(nfp_prog));

                emit_alu(nfp_prog, imm_b(nfp_prog),
                         stack_reg(nfp_prog), ALU_OP_ADD, stack_off_reg);

                needs_inc = true;
        }

        narrow_ld = clr_gpr && size < 8;

        if (lm3) {
                unsigned int nop_cnt;

                emit_csr_wr(nfp_prog, imm_b(nfp_prog), NFP_CSR_ACT_LM_ADDR3);
                /* For size < 4 one slot will be filled by zeroing of upper,
                 * but be careful, that zeroing could be eliminated by zext
                 * optimization.
                 */
                nop_cnt = narrow_ld && meta->flags & FLAG_INSN_DO_ZEXT ? 2 : 3;
                wrp_nops(nfp_prog, nop_cnt);
        }

        if (narrow_ld)
                wrp_zext(nfp_prog, meta, gpr);

        while (size) {
                u32 slice_end;
                u8 slice_size;

                slice_size = min(size, 4 - gpr_byte);
                slice_end = min(off + slice_size, round_up(off + 1, 4));
                slice_size = slice_end - off;

                last = slice_size == size;

                if (needs_inc)
                        off %= 4;

                ret = step(nfp_prog, gpr, gpr_byte, off, slice_size,
                           first, gpr != prev_gpr, last, lm3, needs_inc);
                if (ret)
                        return ret;

                prev_gpr = gpr;
                first = false;

                gpr_byte += slice_size;
                if (gpr_byte >= 4) {
                        gpr_byte -= 4;
                        gpr++;
                }

                size -= slice_size;
                off += slice_size;
        }

        return 0;
}

static void
wrp_alu_imm(struct nfp_prog *nfp_prog, u8 dst, enum alu_op alu_op, u32 imm)
{
        swreg tmp_reg;

        if (alu_op == ALU_OP_AND) {
                if (!imm)
                        wrp_immed(nfp_prog, reg_both(dst), 0);
                if (!imm || !~imm)
                        return;
        }
        if (alu_op == ALU_OP_OR) {
                if (!~imm)
                        wrp_immed(nfp_prog, reg_both(dst), ~0U);
                if (!imm || !~imm)
                        return;
        }
        if (alu_op == ALU_OP_XOR) {
                if (!~imm)
                        emit_alu(nfp_prog, reg_both(dst), reg_none(),
                                 ALU_OP_NOT, reg_b(dst));
                if (!imm || !~imm)
                        return;
        }

        tmp_reg = ur_load_imm_any(nfp_prog, imm, imm_b(nfp_prog));
        emit_alu(nfp_prog, reg_both(dst), reg_a(dst), alu_op, tmp_reg);
}

static int
wrp_alu64_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              enum alu_op alu_op, bool skip)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 imm = insn->imm; /* sign extend */

        if (skip) {
                meta->flags |= FLAG_INSN_SKIP_NOOP;
                return 0;
        }

        wrp_alu_imm(nfp_prog, insn->dst_reg * 2, alu_op, imm & ~0U);
        wrp_alu_imm(nfp_prog, insn->dst_reg * 2 + 1, alu_op, imm >> 32);

        return 0;
}

static int
wrp_alu64_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              enum alu_op alu_op)
{
        u8 dst = meta->insn.dst_reg * 2, src = meta->insn.src_reg * 2;

        emit_alu(nfp_prog, reg_both(dst), reg_a(dst), alu_op, reg_b(src));
        emit_alu(nfp_prog, reg_both(dst + 1),
                 reg_a(dst + 1), alu_op, reg_b(src + 1));

        return 0;
}

static int
wrp_alu32_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              enum alu_op alu_op)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        wrp_alu_imm(nfp_prog, dst, alu_op, insn->imm);
        wrp_zext(nfp_prog, meta, dst);

        return 0;
}

static int
wrp_alu32_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              enum alu_op alu_op)
{
        u8 dst = meta->insn.dst_reg * 2, src = meta->insn.src_reg * 2;

        emit_alu(nfp_prog, reg_both(dst), reg_a(dst), alu_op, reg_b(src));
        wrp_zext(nfp_prog, meta, dst);

        return 0;
}

static void
wrp_test_reg_one(struct nfp_prog *nfp_prog, u8 dst, enum alu_op alu_op, u8 src,
                 enum br_mask br_mask, u16 off)
{
        emit_alu(nfp_prog, reg_none(), reg_a(dst), alu_op, reg_b(src));
        emit_br(nfp_prog, br_mask, off, 0);
}

static int
wrp_test_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
             enum alu_op alu_op, enum br_mask br_mask)
{
        const struct bpf_insn *insn = &meta->insn;

        wrp_test_reg_one(nfp_prog, insn->dst_reg * 2, alu_op,
                         insn->src_reg * 2, br_mask, insn->off);
        if (is_mbpf_jmp64(meta))
                wrp_test_reg_one(nfp_prog, insn->dst_reg * 2 + 1, alu_op,
                                 insn->src_reg * 2 + 1, br_mask, insn->off);

        return 0;
}

static const struct jmp_code_map {
        enum br_mask br_mask;
        bool swap;
} jmp_code_map[] = {
        [BPF_JGT >> 4]  = { BR_BLO, true },
        [BPF_JGE >> 4]  = { BR_BHS, false },
        [BPF_JLT >> 4]  = { BR_BLO, false },
        [BPF_JLE >> 4]  = { BR_BHS, true },
        [BPF_JSGT >> 4] = { BR_BLT, true },
        [BPF_JSGE >> 4] = { BR_BGE, false },
        [BPF_JSLT >> 4] = { BR_BLT, false },
        [BPF_JSLE >> 4] = { BR_BGE, true },
};

static const struct jmp_code_map *nfp_jmp_code_get(struct nfp_insn_meta *meta)
{
        unsigned int op;

        op = BPF_OP(meta->insn.code) >> 4;
        /* br_mask of 0 is BR_BEQ which we don't use in jump code table */
        if (WARN_ONCE(op >= ARRAY_SIZE(jmp_code_map) ||
                      !jmp_code_map[op].br_mask,
                      "no code found for jump instruction"))
                return NULL;

        return &jmp_code_map[op];
}

static int cmp_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 imm = insn->imm; /* sign extend */
        const struct jmp_code_map *code;
        enum alu_op alu_op, carry_op;
        u8 reg = insn->dst_reg * 2;
        swreg tmp_reg;

        code = nfp_jmp_code_get(meta);
        if (!code)
                return -EINVAL;

        alu_op = meta->jump_neg_op ? ALU_OP_ADD : ALU_OP_SUB;
        carry_op = meta->jump_neg_op ? ALU_OP_ADD_C : ALU_OP_SUB_C;

        tmp_reg = ur_load_imm_any(nfp_prog, imm & ~0U, imm_b(nfp_prog));
        if (!code->swap)
                emit_alu(nfp_prog, reg_none(), reg_a(reg), alu_op, tmp_reg);
        else
                emit_alu(nfp_prog, reg_none(), tmp_reg, alu_op, reg_a(reg));

        if (is_mbpf_jmp64(meta)) {
                tmp_reg = ur_load_imm_any(nfp_prog, imm >> 32, imm_b(nfp_prog));
                if (!code->swap)
                        emit_alu(nfp_prog, reg_none(),
                                 reg_a(reg + 1), carry_op, tmp_reg);
                else
                        emit_alu(nfp_prog, reg_none(),
                                 tmp_reg, carry_op, reg_a(reg + 1));
        }

        emit_br(nfp_prog, code->br_mask, insn->off, 0);

        return 0;
}

static int cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        const struct jmp_code_map *code;
        u8 areg, breg;

        code = nfp_jmp_code_get(meta);
        if (!code)
                return -EINVAL;

        areg = insn->dst_reg * 2;
        breg = insn->src_reg * 2;

        if (code->swap) {
                areg ^= breg;
                breg ^= areg;
                areg ^= breg;
        }

        emit_alu(nfp_prog, reg_none(), reg_a(areg), ALU_OP_SUB, reg_b(breg));
        if (is_mbpf_jmp64(meta))
                emit_alu(nfp_prog, reg_none(),
                         reg_a(areg + 1), ALU_OP_SUB_C, reg_b(breg + 1));
        emit_br(nfp_prog, code->br_mask, insn->off, 0);

        return 0;
}

static void wrp_end32(struct nfp_prog *nfp_prog, swreg reg_in, u8 gpr_out)
{
        emit_ld_field(nfp_prog, reg_both(gpr_out), 0xf, reg_in,
                      SHF_SC_R_ROT, 8);
        emit_ld_field(nfp_prog, reg_both(gpr_out), 0x5, reg_a(gpr_out),
                      SHF_SC_R_ROT, 16);
}

static void
wrp_mul_u32(struct nfp_prog *nfp_prog, swreg dst_hi, swreg dst_lo, swreg lreg,
            swreg rreg, bool gen_high_half)
{
        emit_mul(nfp_prog, lreg, MUL_TYPE_START, MUL_STEP_NONE, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_32x32, MUL_STEP_1, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_32x32, MUL_STEP_2, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_32x32, MUL_STEP_3, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_32x32, MUL_STEP_4, rreg);
        emit_mul(nfp_prog, dst_lo, MUL_TYPE_STEP_32x32, MUL_LAST, reg_none());
        if (gen_high_half)
                emit_mul(nfp_prog, dst_hi, MUL_TYPE_STEP_32x32, MUL_LAST_2,
                         reg_none());
        else
                wrp_immed(nfp_prog, dst_hi, 0);
}

static void
wrp_mul_u16(struct nfp_prog *nfp_prog, swreg dst_hi, swreg dst_lo, swreg lreg,
            swreg rreg)
{
        emit_mul(nfp_prog, lreg, MUL_TYPE_START, MUL_STEP_NONE, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_16x16, MUL_STEP_1, rreg);
        emit_mul(nfp_prog, lreg, MUL_TYPE_STEP_16x16, MUL_STEP_2, rreg);
        emit_mul(nfp_prog, dst_lo, MUL_TYPE_STEP_16x16, MUL_LAST, reg_none());
}

static int
wrp_mul(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
        bool gen_high_half, bool ropnd_from_reg)
{
        swreg multiplier, multiplicand, dst_hi, dst_lo;
        const struct bpf_insn *insn = &meta->insn;
        u32 lopnd_max, ropnd_max;
        u8 dst_reg;

        dst_reg = insn->dst_reg;
        multiplicand = reg_a(dst_reg * 2);
        dst_hi = reg_both(dst_reg * 2 + 1);
        dst_lo = reg_both(dst_reg * 2);
        lopnd_max = meta->umax_dst;
        if (ropnd_from_reg) {
                multiplier = reg_b(insn->src_reg * 2);
                ropnd_max = meta->umax_src;
        } else {
                u32 imm = insn->imm;

                multiplier = ur_load_imm_any(nfp_prog, imm, imm_b(nfp_prog));
                ropnd_max = imm;
        }
        if (lopnd_max > U16_MAX || ropnd_max > U16_MAX)
                wrp_mul_u32(nfp_prog, dst_hi, dst_lo, multiplicand, multiplier,
                            gen_high_half);
        else
                wrp_mul_u16(nfp_prog, dst_hi, dst_lo, multiplicand, multiplier);

        return 0;
}

static int wrp_div_imm(struct nfp_prog *nfp_prog, u8 dst, u64 imm)
{
        swreg dst_both = reg_both(dst), dst_a = reg_a(dst), dst_b = reg_a(dst);
        struct reciprocal_value_adv rvalue;
        u8 pre_shift, exp;
        swreg magic;

        if (imm > U32_MAX) {
                wrp_immed(nfp_prog, dst_both, 0);
                return 0;
        }

        /* NOTE: because we are using "reciprocal_value_adv" which doesn't
         * support "divisor > (1u << 31)", we need to JIT separate NFP sequence
         * to handle such case which actually equals to the result of unsigned
         * comparison "dst >= imm" which could be calculated using the following
         * NFP sequence:
         *
         *  alu[--, dst, -, imm]
         *  immed[imm, 0]
         *  alu[dst, imm, +carry, 0]
         *
         */
        if (imm > 1U << 31) {
                swreg tmp_b = ur_load_imm_any(nfp_prog, imm, imm_b(nfp_prog));

                emit_alu(nfp_prog, reg_none(), dst_a, ALU_OP_SUB, tmp_b);
                wrp_immed(nfp_prog, imm_a(nfp_prog), 0);
                emit_alu(nfp_prog, dst_both, imm_a(nfp_prog), ALU_OP_ADD_C,
                         reg_imm(0));
                return 0;
        }

        rvalue = reciprocal_value_adv(imm, 32);
        exp = rvalue.exp;
        if (rvalue.is_wide_m && !(imm & 1)) {
                pre_shift = fls(imm & -imm) - 1;
                rvalue = reciprocal_value_adv(imm >> pre_shift, 32 - pre_shift);
        } else {
                pre_shift = 0;
        }
        magic = ur_load_imm_any(nfp_prog, rvalue.m, imm_b(nfp_prog));
        if (imm == 1U << exp) {
                emit_shf(nfp_prog, dst_both, reg_none(), SHF_OP_NONE, dst_b,
                         SHF_SC_R_SHF, exp);
        } else if (rvalue.is_wide_m) {
                wrp_mul_u32(nfp_prog, imm_both(nfp_prog), reg_none(), dst_a,
                            magic, true);
                emit_alu(nfp_prog, dst_both, dst_a, ALU_OP_SUB,
                         imm_b(nfp_prog));
                emit_shf(nfp_prog, dst_both, reg_none(), SHF_OP_NONE, dst_b,
                         SHF_SC_R_SHF, 1);
                emit_alu(nfp_prog, dst_both, dst_a, ALU_OP_ADD,
                         imm_b(nfp_prog));
                emit_shf(nfp_prog, dst_both, reg_none(), SHF_OP_NONE, dst_b,
                         SHF_SC_R_SHF, rvalue.sh - 1);
        } else {
                if (pre_shift)
                        emit_shf(nfp_prog, dst_both, reg_none(), SHF_OP_NONE,
                                 dst_b, SHF_SC_R_SHF, pre_shift);
                wrp_mul_u32(nfp_prog, dst_both, reg_none(), dst_a, magic, true);
                emit_shf(nfp_prog, dst_both, reg_none(), SHF_OP_NONE,
                         dst_b, SHF_SC_R_SHF, rvalue.sh);
        }

        return 0;
}

static int adjust_head(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        swreg tmp = imm_a(nfp_prog), tmp_len = imm_b(nfp_prog);
        struct nfp_bpf_cap_adjust_head *adjust_head;
        u32 ret_einval, end;

        adjust_head = &nfp_prog->bpf->adjust_head;

        /* Optimized version - 5 vs 14 cycles */
        if (nfp_prog->adjust_head_location != UINT_MAX) {
                if (WARN_ON_ONCE(nfp_prog->adjust_head_location != meta->n))
                        return -EINVAL;

                emit_alu(nfp_prog, pptr_reg(nfp_prog),
                         reg_a(2 * 2), ALU_OP_ADD, pptr_reg(nfp_prog));
                emit_alu(nfp_prog, plen_reg(nfp_prog),
                         plen_reg(nfp_prog), ALU_OP_SUB, reg_a(2 * 2));
                emit_alu(nfp_prog, pv_len(nfp_prog),
                         pv_len(nfp_prog), ALU_OP_SUB, reg_a(2 * 2));

                wrp_immed(nfp_prog, reg_both(0), 0);
                wrp_immed(nfp_prog, reg_both(1), 0);

                /* TODO: when adjust head is guaranteed to succeed we can
                 * also eliminate the following if (r0 == 0) branch.
                 */

                return 0;
        }

        ret_einval = nfp_prog_current_offset(nfp_prog) + 14;
        end = ret_einval + 2;

        /* We need to use a temp because offset is just a part of the pkt ptr */
        emit_alu(nfp_prog, tmp,
                 reg_a(2 * 2), ALU_OP_ADD_2B, pptr_reg(nfp_prog));

        /* Validate result will fit within FW datapath constraints */
        emit_alu(nfp_prog, reg_none(),
                 tmp, ALU_OP_SUB, reg_imm(adjust_head->off_min));
        emit_br(nfp_prog, BR_BLO, ret_einval, 0);
        emit_alu(nfp_prog, reg_none(),
                 reg_imm(adjust_head->off_max), ALU_OP_SUB, tmp);
        emit_br(nfp_prog, BR_BLO, ret_einval, 0);

        /* Validate the length is at least ETH_HLEN */
        emit_alu(nfp_prog, tmp_len,
                 plen_reg(nfp_prog), ALU_OP_SUB, reg_a(2 * 2));
        emit_alu(nfp_prog, reg_none(),
                 tmp_len, ALU_OP_SUB, reg_imm(ETH_HLEN));
        emit_br(nfp_prog, BR_BMI, ret_einval, 0);

        /* Load the ret code */
        wrp_immed(nfp_prog, reg_both(0), 0);
        wrp_immed(nfp_prog, reg_both(1), 0);

        /* Modify the packet metadata */
        emit_ld_field(nfp_prog, pptr_reg(nfp_prog), 0x3, tmp, SHF_SC_NONE, 0);

        /* Skip over the -EINVAL ret code (defer 2) */
        emit_br(nfp_prog, BR_UNC, end, 2);

        emit_alu(nfp_prog, plen_reg(nfp_prog),
                 plen_reg(nfp_prog), ALU_OP_SUB, reg_a(2 * 2));
        emit_alu(nfp_prog, pv_len(nfp_prog),
                 pv_len(nfp_prog), ALU_OP_SUB, reg_a(2 * 2));

        /* return -EINVAL target */
        if (!nfp_prog_confirm_current_offset(nfp_prog, ret_einval))
                return -EINVAL;

        wrp_immed(nfp_prog, reg_both(0), -22);
        wrp_immed(nfp_prog, reg_both(1), ~0);

        if (!nfp_prog_confirm_current_offset(nfp_prog, end))
                return -EINVAL;

        return 0;
}

static int adjust_tail(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        u32 ret_einval, end;
        swreg plen, delta;

        BUILD_BUG_ON(plen_reg(nfp_prog) != reg_b(STATIC_REG_PKT_LEN));

        plen = imm_a(nfp_prog);
        delta = reg_a(2 * 2);

        ret_einval = nfp_prog_current_offset(nfp_prog) + 9;
        end = nfp_prog_current_offset(nfp_prog) + 11;

        /* Calculate resulting length */
        emit_alu(nfp_prog, plen, plen_reg(nfp_prog), ALU_OP_ADD, delta);
        /* delta == 0 is not allowed by the kernel, add must overflow to make
         * length smaller.
         */
        emit_br(nfp_prog, BR_BCC, ret_einval, 0);

        /* if (new_len < 14) then -EINVAL */
        emit_alu(nfp_prog, reg_none(), plen, ALU_OP_SUB, reg_imm(ETH_HLEN));
        emit_br(nfp_prog, BR_BMI, ret_einval, 0);

        emit_alu(nfp_prog, plen_reg(nfp_prog),
                 plen_reg(nfp_prog), ALU_OP_ADD, delta);
        emit_alu(nfp_prog, pv_len(nfp_prog),
                 pv_len(nfp_prog), ALU_OP_ADD, delta);

        emit_br(nfp_prog, BR_UNC, end, 2);
        wrp_immed(nfp_prog, reg_both(0), 0);
        wrp_immed(nfp_prog, reg_both(1), 0);

        if (!nfp_prog_confirm_current_offset(nfp_prog, ret_einval))
                return -EINVAL;

        wrp_immed(nfp_prog, reg_both(0), -22);
        wrp_immed(nfp_prog, reg_both(1), ~0);

        if (!nfp_prog_confirm_current_offset(nfp_prog, end))
                return -EINVAL;

        return 0;
}

static int
map_call_stack_common(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        bool load_lm_ptr;
        u32 ret_tgt;
        s64 lm_off;

        /* We only have to reload LM0 if the key is not at start of stack */
        lm_off = nfp_prog->stack_frame_depth;
        lm_off += meta->arg2.reg.var_off.value + meta->arg2.reg.off;
        load_lm_ptr = meta->arg2.var_off || lm_off;

        /* Set LM0 to start of key */
        if (load_lm_ptr)
                emit_csr_wr(nfp_prog, reg_b(2 * 2), NFP_CSR_ACT_LM_ADDR0);
        if (meta->func_id == BPF_FUNC_map_update_elem)
                emit_csr_wr(nfp_prog, reg_b(3 * 2), NFP_CSR_ACT_LM_ADDR2);

        emit_br_relo(nfp_prog, BR_UNC, BR_OFF_RELO + meta->func_id,
                     2, RELO_BR_HELPER);
        ret_tgt = nfp_prog_current_offset(nfp_prog) + 2;

        /* Load map ID into A0 */
        wrp_mov(nfp_prog, reg_a(0), reg_a(2));

        /* Load the return address into B0 */
        wrp_immed_relo(nfp_prog, reg_b(0), ret_tgt, RELO_IMMED_REL);

        if (!nfp_prog_confirm_current_offset(nfp_prog, ret_tgt))
                return -EINVAL;

        /* Reset the LM0 pointer */
        if (!load_lm_ptr)
                return 0;

        emit_csr_wr(nfp_prog, stack_reg(nfp_prog), NFP_CSR_ACT_LM_ADDR0);
        wrp_nops(nfp_prog, 3);

        return 0;
}

static int
nfp_get_prandom_u32(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        __emit_csr_rd(nfp_prog, NFP_CSR_PSEUDO_RND_NUM);
        /* CSR value is read in following immed[gpr, 0] */
        emit_immed(nfp_prog, reg_both(0), 0,
                   IMMED_WIDTH_ALL, false, IMMED_SHIFT_0B);
        emit_immed(nfp_prog, reg_both(1), 0,
                   IMMED_WIDTH_ALL, false, IMMED_SHIFT_0B);
        return 0;
}

static int
nfp_perf_event_output(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        swreg ptr_type;
        u32 ret_tgt;

        ptr_type = ur_load_imm_any(nfp_prog, meta->arg1.type, imm_a(nfp_prog));

        ret_tgt = nfp_prog_current_offset(nfp_prog) + 3;

        emit_br_relo(nfp_prog, BR_UNC, BR_OFF_RELO + meta->func_id,
                     2, RELO_BR_HELPER);

        /* Load ptr type into A1 */
        wrp_mov(nfp_prog, reg_a(1), ptr_type);

        /* Load the return address into B0 */
        wrp_immed_relo(nfp_prog, reg_b(0), ret_tgt, RELO_IMMED_REL);

        if (!nfp_prog_confirm_current_offset(nfp_prog, ret_tgt))
                return -EINVAL;

        return 0;
}

static int
nfp_queue_select(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        u32 jmp_tgt;

        jmp_tgt = nfp_prog_current_offset(nfp_prog) + 5;

        /* Make sure the queue id fits into FW field */
        emit_alu(nfp_prog, reg_none(), reg_a(meta->insn.src_reg * 2),
                 ALU_OP_AND_NOT_B, reg_imm(0xff));
        emit_br(nfp_prog, BR_BEQ, jmp_tgt, 2);

        /* Set the 'queue selected' bit and the queue value */
        emit_shf(nfp_prog, pv_qsel_set(nfp_prog),
                 pv_qsel_set(nfp_prog), SHF_OP_OR, reg_imm(1),
                 SHF_SC_L_SHF, PKT_VEL_QSEL_SET_BIT);
        emit_ld_field(nfp_prog,
                      pv_qsel_val(nfp_prog), 0x1, reg_b(meta->insn.src_reg * 2),
                      SHF_SC_NONE, 0);
        /* Delay slots end here, we will jump over next instruction if queue
         * value fits into the field.
         */
        emit_ld_field(nfp_prog,
                      pv_qsel_val(nfp_prog), 0x1, reg_imm(NFP_NET_RXR_MAX),
                      SHF_SC_NONE, 0);

        if (!nfp_prog_confirm_current_offset(nfp_prog, jmp_tgt))
                return -EINVAL;

        return 0;
}

/* --- Callbacks --- */
static int mov_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;
        u8 src = insn->src_reg * 2;

        if (insn->src_reg == BPF_REG_10) {
                swreg stack_depth_reg;

                stack_depth_reg = ur_load_imm_any(nfp_prog,
                                                  nfp_prog->stack_frame_depth,
                                                  stack_imm(nfp_prog));
                emit_alu(nfp_prog, reg_both(dst), stack_reg(nfp_prog),
                         ALU_OP_ADD, stack_depth_reg);
                wrp_immed(nfp_prog, reg_both(dst + 1), 0);
        } else {
                wrp_reg_mov(nfp_prog, dst, src);
                wrp_reg_mov(nfp_prog, dst + 1, src + 1);
        }

        return 0;
}

static int mov_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        u64 imm = meta->insn.imm; /* sign extend */

        wrp_immed(nfp_prog, reg_both(meta->insn.dst_reg * 2), imm & ~0U);
        wrp_immed(nfp_prog, reg_both(meta->insn.dst_reg * 2 + 1), imm >> 32);

        return 0;
}

static int xor_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_reg(nfp_prog, meta, ALU_OP_XOR);
}

static int xor_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_imm(nfp_prog, meta, ALU_OP_XOR, !meta->insn.imm);
}

static int and_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_reg(nfp_prog, meta, ALU_OP_AND);
}

static int and_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_imm(nfp_prog, meta, ALU_OP_AND, !~meta->insn.imm);
}

static int or_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_reg(nfp_prog, meta, ALU_OP_OR);
}

static int or_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu64_imm(nfp_prog, meta, ALU_OP_OR, !meta->insn.imm);
}

static int add_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2),
                 reg_a(insn->dst_reg * 2), ALU_OP_ADD,
                 reg_b(insn->src_reg * 2));
        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2 + 1),
                 reg_a(insn->dst_reg * 2 + 1), ALU_OP_ADD_C,
                 reg_b(insn->src_reg * 2 + 1));

        return 0;
}

static int add_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 imm = insn->imm; /* sign extend */

        wrp_alu_imm(nfp_prog, insn->dst_reg * 2, ALU_OP_ADD, imm & ~0U);
        wrp_alu_imm(nfp_prog, insn->dst_reg * 2 + 1, ALU_OP_ADD_C, imm >> 32);

        return 0;
}

static int sub_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2),
                 reg_a(insn->dst_reg * 2), ALU_OP_SUB,
                 reg_b(insn->src_reg * 2));
        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2 + 1),
                 reg_a(insn->dst_reg * 2 + 1), ALU_OP_SUB_C,
                 reg_b(insn->src_reg * 2 + 1));

        return 0;
}

static int sub_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 imm = insn->imm; /* sign extend */

        wrp_alu_imm(nfp_prog, insn->dst_reg * 2, ALU_OP_SUB, imm & ~0U);
        wrp_alu_imm(nfp_prog, insn->dst_reg * 2 + 1, ALU_OP_SUB_C, imm >> 32);

        return 0;
}

static int mul_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_mul(nfp_prog, meta, true, true);
}

static int mul_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_mul(nfp_prog, meta, true, false);
}

static int div_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        return wrp_div_imm(nfp_prog, insn->dst_reg * 2, insn->imm);
}

static int div_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        /* NOTE: verifier hook has rejected cases for which verifier doesn't
         * know whether the source operand is constant or not.
         */
        return wrp_div_imm(nfp_prog, meta->insn.dst_reg * 2, meta->umin_src);
}

static int neg_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2), reg_imm(0),
                 ALU_OP_SUB, reg_b(insn->dst_reg * 2));
        emit_alu(nfp_prog, reg_both(insn->dst_reg * 2 + 1), reg_imm(0),
                 ALU_OP_SUB_C, reg_b(insn->dst_reg * 2 + 1));

        return 0;
}

/* Pseudo code:
 *   if shift_amt >= 32
 *     dst_high = dst_low << shift_amt[4:0]
 *     dst_low = 0;
 *   else
 *     dst_high = (dst_high, dst_low) >> (32 - shift_amt)
 *     dst_low = dst_low << shift_amt
 *
 * The indirect shift will use the same logic at runtime.
 */
static int __shl_imm64(struct nfp_prog *nfp_prog, u8 dst, u8 shift_amt)
{
        if (!shift_amt)
                return 0;

        if (shift_amt < 32) {
                emit_shf(nfp_prog, reg_both(dst + 1), reg_a(dst + 1),
                         SHF_OP_NONE, reg_b(dst), SHF_SC_R_DSHF,
                         32 - shift_amt);
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_L_SHF, shift_amt);
        } else if (shift_amt == 32) {
                wrp_reg_mov(nfp_prog, dst + 1, dst);
                wrp_immed(nfp_prog, reg_both(dst), 0);
        } else if (shift_amt > 32) {
                emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_L_SHF, shift_amt - 32);
                wrp_immed(nfp_prog, reg_both(dst), 0);
        }

        return 0;
}

static int shl_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __shl_imm64(nfp_prog, dst, insn->imm);
}

static void shl_reg64_lt32_high(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, imm_both(nfp_prog), reg_imm(32), ALU_OP_SUB,
                 reg_b(src));
        emit_alu(nfp_prog, reg_none(), imm_a(nfp_prog), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst + 1), reg_a(dst + 1), SHF_OP_NONE,
                       reg_b(dst), SHF_SC_R_DSHF);
}

/* NOTE: for indirect left shift, HIGH part should be calculated first. */
static void shl_reg64_lt32_low(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                       reg_b(dst), SHF_SC_L_SHF);
}

static void shl_reg64_lt32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        shl_reg64_lt32_high(nfp_prog, dst, src);
        shl_reg64_lt32_low(nfp_prog, dst, src);
}

static void shl_reg64_ge32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_NONE,
                       reg_b(dst), SHF_SC_L_SHF);
        wrp_immed(nfp_prog, reg_both(dst), 0);
}

static int shl_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __shl_imm64(nfp_prog, dst, umin);

        src = insn->src_reg * 2;
        if (umax < 32) {
                shl_reg64_lt32(nfp_prog, dst, src);
        } else if (umin >= 32) {
                shl_reg64_ge32(nfp_prog, dst, src);
        } else {
                /* Generate different instruction sequences depending on runtime
                 * value of shift amount.
                 */
                u16 label_ge32, label_end;

                label_ge32 = nfp_prog_current_offset(nfp_prog) + 7;
                emit_br_bset(nfp_prog, reg_a(src), 5, label_ge32, 0);

                shl_reg64_lt32_high(nfp_prog, dst, src);
                label_end = nfp_prog_current_offset(nfp_prog) + 6;
                emit_br(nfp_prog, BR_UNC, label_end, 2);
                /* shl_reg64_lt32_low packed in delay slot. */
                shl_reg64_lt32_low(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_ge32))
                        return -EINVAL;
                shl_reg64_ge32(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_end))
                        return -EINVAL;
        }

        return 0;
}

/* Pseudo code:
 *   if shift_amt >= 32
 *     dst_high = 0;
 *     dst_low = dst_high >> shift_amt[4:0]
 *   else
 *     dst_high = dst_high >> shift_amt
 *     dst_low = (dst_high, dst_low) >> shift_amt
 *
 * The indirect shift will use the same logic at runtime.
 */
static int __shr_imm64(struct nfp_prog *nfp_prog, u8 dst, u8 shift_amt)
{
        if (!shift_amt)
                return 0;

        if (shift_amt < 32) {
                emit_shf(nfp_prog, reg_both(dst), reg_a(dst + 1), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_R_DSHF, shift_amt);
                emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_NONE,
                         reg_b(dst + 1), SHF_SC_R_SHF, shift_amt);
        } else if (shift_amt == 32) {
                wrp_reg_mov(nfp_prog, dst, dst + 1);
                wrp_immed(nfp_prog, reg_both(dst + 1), 0);
        } else if (shift_amt > 32) {
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                         reg_b(dst + 1), SHF_SC_R_SHF, shift_amt - 32);
                wrp_immed(nfp_prog, reg_both(dst + 1), 0);
        }

        return 0;
}

static int shr_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __shr_imm64(nfp_prog, dst, insn->imm);
}

/* NOTE: for indirect right shift, LOW part should be calculated first. */
static void shr_reg64_lt32_high(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_NONE,
                       reg_b(dst + 1), SHF_SC_R_SHF);
}

static void shr_reg64_lt32_low(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_a(dst + 1), SHF_OP_NONE,
                       reg_b(dst), SHF_SC_R_DSHF);
}

static void shr_reg64_lt32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        shr_reg64_lt32_low(nfp_prog, dst, src);
        shr_reg64_lt32_high(nfp_prog, dst, src);
}

static void shr_reg64_ge32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                       reg_b(dst + 1), SHF_SC_R_SHF);
        wrp_immed(nfp_prog, reg_both(dst + 1), 0);
}

static int shr_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __shr_imm64(nfp_prog, dst, umin);

        src = insn->src_reg * 2;
        if (umax < 32) {
                shr_reg64_lt32(nfp_prog, dst, src);
        } else if (umin >= 32) {
                shr_reg64_ge32(nfp_prog, dst, src);
        } else {
                /* Generate different instruction sequences depending on runtime
                 * value of shift amount.
                 */
                u16 label_ge32, label_end;

                label_ge32 = nfp_prog_current_offset(nfp_prog) + 6;
                emit_br_bset(nfp_prog, reg_a(src), 5, label_ge32, 0);
                shr_reg64_lt32_low(nfp_prog, dst, src);
                label_end = nfp_prog_current_offset(nfp_prog) + 6;
                emit_br(nfp_prog, BR_UNC, label_end, 2);
                /* shr_reg64_lt32_high packed in delay slot. */
                shr_reg64_lt32_high(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_ge32))
                        return -EINVAL;
                shr_reg64_ge32(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_end))
                        return -EINVAL;
        }

        return 0;
}

/* Code logic is the same as __shr_imm64 except ashr requires signedness bit
 * told through PREV_ALU result.
 */
static int __ashr_imm64(struct nfp_prog *nfp_prog, u8 dst, u8 shift_amt)
{
        if (!shift_amt)
                return 0;

        if (shift_amt < 32) {
                emit_shf(nfp_prog, reg_both(dst), reg_a(dst + 1), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_R_DSHF, shift_amt);
                /* Set signedness bit. */
                emit_alu(nfp_prog, reg_none(), reg_a(dst + 1), ALU_OP_OR,
                         reg_imm(0));
                emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_ASHR,
                         reg_b(dst + 1), SHF_SC_R_SHF, shift_amt);
        } else if (shift_amt == 32) {
                /* NOTE: this also helps setting signedness bit. */
                wrp_reg_mov(nfp_prog, dst, dst + 1);
                emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_ASHR,
                         reg_b(dst + 1), SHF_SC_R_SHF, 31);
        } else if (shift_amt > 32) {
                emit_alu(nfp_prog, reg_none(), reg_a(dst + 1), ALU_OP_OR,
                         reg_imm(0));
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR,
                         reg_b(dst + 1), SHF_SC_R_SHF, shift_amt - 32);
                emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_ASHR,
                         reg_b(dst + 1), SHF_SC_R_SHF, 31);
        }

        return 0;
}

static int ashr_imm64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __ashr_imm64(nfp_prog, dst, insn->imm);
}

static void ashr_reg64_lt32_high(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        /* NOTE: the first insn will set both indirect shift amount (source A)
         * and signedness bit (MSB of result).
         */
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_b(dst + 1));
        emit_shf_indir(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_ASHR,
                       reg_b(dst + 1), SHF_SC_R_SHF);
}

static void ashr_reg64_lt32_low(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        /* NOTE: it is the same as logic shift because we don't need to shift in
         * signedness bit when the shift amount is less than 32.
         */
        return shr_reg64_lt32_low(nfp_prog, dst, src);
}

static void ashr_reg64_lt32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        ashr_reg64_lt32_low(nfp_prog, dst, src);
        ashr_reg64_lt32_high(nfp_prog, dst, src);
}

static void ashr_reg64_ge32(struct nfp_prog *nfp_prog, u8 dst, u8 src)
{
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_b(dst + 1));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR,
                       reg_b(dst + 1), SHF_SC_R_SHF);
        emit_shf(nfp_prog, reg_both(dst + 1), reg_none(), SHF_OP_ASHR,
                 reg_b(dst + 1), SHF_SC_R_SHF, 31);
}

/* Like ashr_imm64, but need to use indirect shift. */
static int ashr_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __ashr_imm64(nfp_prog, dst, umin);

        src = insn->src_reg * 2;
        if (umax < 32) {
                ashr_reg64_lt32(nfp_prog, dst, src);
        } else if (umin >= 32) {
                ashr_reg64_ge32(nfp_prog, dst, src);
        } else {
                u16 label_ge32, label_end;

                label_ge32 = nfp_prog_current_offset(nfp_prog) + 6;
                emit_br_bset(nfp_prog, reg_a(src), 5, label_ge32, 0);
                ashr_reg64_lt32_low(nfp_prog, dst, src);
                label_end = nfp_prog_current_offset(nfp_prog) + 6;
                emit_br(nfp_prog, BR_UNC, label_end, 2);
                /* ashr_reg64_lt32_high packed in delay slot. */
                ashr_reg64_lt32_high(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_ge32))
                        return -EINVAL;
                ashr_reg64_ge32(nfp_prog, dst, src);

                if (!nfp_prog_confirm_current_offset(nfp_prog, label_end))
                        return -EINVAL;
        }

        return 0;
}

static int mov_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        wrp_reg_mov(nfp_prog, insn->dst_reg * 2,  insn->src_reg * 2);
        wrp_immed(nfp_prog, reg_both(insn->dst_reg * 2 + 1), 0);

        return 0;
}

static int mov_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;

        wrp_immed(nfp_prog, reg_both(insn->dst_reg * 2), insn->imm);
        wrp_immed(nfp_prog, reg_both(insn->dst_reg * 2 + 1), 0);

        return 0;
}

static int xor_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_reg(nfp_prog, meta, ALU_OP_XOR);
}

static int xor_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_imm(nfp_prog, meta, ALU_OP_XOR);
}

static int and_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_reg(nfp_prog, meta, ALU_OP_AND);
}

static int and_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_imm(nfp_prog, meta, ALU_OP_AND);
}

static int or_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_reg(nfp_prog, meta, ALU_OP_OR);
}

static int or_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_imm(nfp_prog, meta, ALU_OP_OR);
}

static int add_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_reg(nfp_prog, meta, ALU_OP_ADD);
}

static int add_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_imm(nfp_prog, meta, ALU_OP_ADD);
}

static int sub_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_reg(nfp_prog, meta, ALU_OP_SUB);
}

static int sub_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_alu32_imm(nfp_prog, meta, ALU_OP_SUB);
}

static int mul_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_mul(nfp_prog, meta, false, true);
}

static int mul_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return wrp_mul(nfp_prog, meta, false, false);
}

static int div_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return div_reg64(nfp_prog, meta);
}

static int div_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return div_imm64(nfp_prog, meta);
}

static int neg_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        u8 dst = meta->insn.dst_reg * 2;

        emit_alu(nfp_prog, reg_both(dst), reg_imm(0), ALU_OP_SUB, reg_b(dst));
        wrp_zext(nfp_prog, meta, dst);

        return 0;
}

static int
__ashr_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, u8 dst,
           u8 shift_amt)
{
        if (shift_amt) {
                /* Set signedness bit (MSB of result). */
                emit_alu(nfp_prog, reg_none(), reg_a(dst), ALU_OP_OR,
                         reg_imm(0));
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR,
                         reg_b(dst), SHF_SC_R_SHF, shift_amt);
        }
        wrp_zext(nfp_prog, meta, dst);

        return 0;
}

static int ashr_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __ashr_imm(nfp_prog, meta, dst, umin);

        src = insn->src_reg * 2;
        /* NOTE: the first insn will set both indirect shift amount (source A)
         * and signedness bit (MSB of result).
         */
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_b(dst));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR,
                       reg_b(dst), SHF_SC_R_SHF);
        wrp_zext(nfp_prog, meta, dst);

        return 0;
}

static int ashr_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __ashr_imm(nfp_prog, meta, dst, insn->imm);
}

static int
__shr_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, u8 dst,
          u8 shift_amt)
{
        if (shift_amt)
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_R_SHF, shift_amt);
        wrp_zext(nfp_prog, meta, dst);
        return 0;
}

static int shr_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __shr_imm(nfp_prog, meta, dst, insn->imm);
}

static int shr_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __shr_imm(nfp_prog, meta, dst, umin);

        src = insn->src_reg * 2;
        emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_imm(0));
        emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                       reg_b(dst), SHF_SC_R_SHF);
        wrp_zext(nfp_prog, meta, dst);
        return 0;
}

static int
__shl_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, u8 dst,
          u8 shift_amt)
{
        if (shift_amt)
                emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_NONE,
                         reg_b(dst), SHF_SC_L_SHF, shift_amt);
        wrp_zext(nfp_prog, meta, dst);
        return 0;
}

static int shl_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 dst = insn->dst_reg * 2;

        return __shl_imm(nfp_prog, meta, dst, insn->imm);
}

static int shl_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u64 umin, umax;
        u8 dst, src;

        dst = insn->dst_reg * 2;
        umin = meta->umin_src;
        umax = meta->umax_src;
        if (umin == umax)
                return __shl_imm(nfp_prog, meta, dst, umin);

        src = insn->src_reg * 2;
        shl_reg64_lt32_low(nfp_prog, dst, src);
        wrp_zext(nfp_prog, meta, dst);
        return 0;
}

static int end_reg32(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        const struct bpf_insn *insn = &meta->insn;
        u8 gpr = insn->dst_reg * 2;

        switch (insn->imm) {
        case 16:
                emit_ld_field(nfp_prog, reg_both(gpr), 0x9, reg_b(gpr),
                              SHF_SC_R_ROT, 8);
                emit_ld_field(nfp_prog, reg_both(gpr), 0xe, reg_a(gpr),
                              SHF_SC_R_SHF, 16);

                wrp_immed(nfp_prog, reg_both(gpr + 1), 0);
                break;
        case 32:
                wrp_end32(nfp_prog, reg_a(gpr), gpr);
                wrp_immed(nfp_prog, reg_both(gpr + 1), 0);
                break;
        case 64:
                wrp_mov(nfp_prog, imm_a(nfp_prog), reg_b(gpr + 1));

                wrp_end32(nfp_prog, reg_a(gpr), gpr + 1);
                wrp_end32(nfp_prog, imm_a(nfp_prog), gpr);
                break;
        }

        return 0;
}

static int imm_ld8_part2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        struct nfp_insn_meta *prev = nfp_meta_prev(meta);
        u32 imm_lo, imm_hi;
        u8 dst;

        dst = prev->insn.dst_reg * 2;
        imm_lo = prev->insn.imm;
        imm_hi = meta->insn.imm;

        wrp_immed(nfp_prog, reg_both(dst), imm_lo);

        /* mov is always 1 insn, load imm may be two, so try to use mov */
        if (imm_hi == imm_lo)
                wrp_mov(nfp_prog, reg_both(dst + 1), reg_a(dst));
        else
                wrp_immed(nfp_prog, reg_both(dst + 1), imm_hi);

        return 0;
}

static int imm_ld8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        meta->double_cb = imm_ld8_part2;
        return 0;
}

static int data_ld1(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ld(nfp_prog, meta, meta->insn.imm, 1);
}

static int data_ld2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ld(nfp_prog, meta, meta->insn.imm, 2);
}

static int data_ld4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ld(nfp_prog, meta, meta->insn.imm, 4);
}

static int data_ind_ld1(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ind_ld(nfp_prog, meta, meta->insn.imm,
                                     meta->insn.src_reg * 2, 1);
}

static int data_ind_ld2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ind_ld(nfp_prog, meta, meta->insn.imm,
                                     meta->insn.src_reg * 2, 2);
}

static int data_ind_ld4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return construct_data_ind_ld(nfp_prog, meta, meta->insn.imm,
                                     meta->insn.src_reg * 2, 4);
}

static int
mem_ldx_stack(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              unsigned int size, unsigned int ptr_off)
{
        return mem_op_stack(nfp_prog, meta, size, ptr_off,
                            meta->insn.dst_reg * 2, meta->insn.src_reg * 2,
                            true, wrp_lmem_load);
}

static int mem_ldx_skb(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                       u8 size)
{
        swreg dst = reg_both(meta->insn.dst_reg * 2);

        switch (meta->insn.off) {
        case offsetof(struct __sk_buff, len):
                if (size != FIELD_SIZEOF(struct __sk_buff, len))
                        return -EOPNOTSUPP;
                wrp_mov(nfp_prog, dst, plen_reg(nfp_prog));
                break;
        case offsetof(struct __sk_buff, data):
                if (size != FIELD_SIZEOF(struct __sk_buff, data))
                        return -EOPNOTSUPP;
                wrp_mov(nfp_prog, dst, pptr_reg(nfp_prog));
                break;
        case offsetof(struct __sk_buff, data_end):
                if (size != FIELD_SIZEOF(struct __sk_buff, data_end))
                        return -EOPNOTSUPP;
                emit_alu(nfp_prog, dst,
                         plen_reg(nfp_prog), ALU_OP_ADD, pptr_reg(nfp_prog));
                break;
        default:
                return -EOPNOTSUPP;
        }

        wrp_immed(nfp_prog, reg_both(meta->insn.dst_reg * 2 + 1), 0);

        return 0;
}

static int mem_ldx_xdp(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                       u8 size)
{
        swreg dst = reg_both(meta->insn.dst_reg * 2);

        switch (meta->insn.off) {
        case offsetof(struct xdp_md, data):
                if (size != FIELD_SIZEOF(struct xdp_md, data))
                        return -EOPNOTSUPP;
                wrp_mov(nfp_prog, dst, pptr_reg(nfp_prog));
                break;
        case offsetof(struct xdp_md, data_end):
                if (size != FIELD_SIZEOF(struct xdp_md, data_end))
                        return -EOPNOTSUPP;
                emit_alu(nfp_prog, dst,
                         plen_reg(nfp_prog), ALU_OP_ADD, pptr_reg(nfp_prog));
                break;
        default:
                return -EOPNOTSUPP;
        }

        wrp_immed(nfp_prog, reg_both(meta->insn.dst_reg * 2 + 1), 0);

        return 0;
}

static int
mem_ldx_data(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
             unsigned int size)
{
        swreg tmp_reg;

        tmp_reg = re_load_imm_any(nfp_prog, meta->insn.off, imm_b(nfp_prog));

        return data_ld_host_order_addr32(nfp_prog, meta, meta->insn.src_reg * 2,
                                         tmp_reg, meta->insn.dst_reg * 2, size);
}

static int
mem_ldx_emem(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
             unsigned int size)
{
        swreg tmp_reg;

        tmp_reg = re_load_imm_any(nfp_prog, meta->insn.off, imm_b(nfp_prog));

        return data_ld_host_order_addr40(nfp_prog, meta, meta->insn.src_reg * 2,
                                         tmp_reg, meta->insn.dst_reg * 2, size);
}

static void
mem_ldx_data_init_pktcache(struct nfp_prog *nfp_prog,
                           struct nfp_insn_meta *meta)
{
        s16 range_start = meta->pkt_cache.range_start;
        s16 range_end = meta->pkt_cache.range_end;
        swreg src_base, off;
        u8 xfer_num, len;
        bool indir;

        off = re_load_imm_any(nfp_prog, range_start, imm_b(nfp_prog));
        src_base = reg_a(meta->insn.src_reg * 2);
        len = range_end - range_start;
        xfer_num = round_up(len, REG_WIDTH) / REG_WIDTH;

        indir = len > 8 * REG_WIDTH;
        /* Setup PREV_ALU for indirect mode. */
        if (indir)
                wrp_immed(nfp_prog, reg_none(),
                          CMD_OVE_LEN | FIELD_PREP(CMD_OV_LEN, xfer_num - 1));

        /* Cache memory into transfer-in registers. */
        emit_cmd_any(nfp_prog, CMD_TGT_READ32_SWAP, CMD_MODE_32b, 0, src_base,
                     off, xfer_num - 1, CMD_CTX_SWAP, indir);
}

static int
mem_ldx_data_from_pktcache_unaligned(struct nfp_prog *nfp_prog,
                                     struct nfp_insn_meta *meta,
                                     unsigned int size)
{
        s16 range_start = meta->pkt_cache.range_start;
        s16 insn_off = meta->insn.off - range_start;
        swreg dst_lo, dst_hi, src_lo, src_mid;
        u8 dst_gpr = meta->insn.dst_reg * 2;
        u8 len_lo = size, len_mid = 0;
        u8 idx = insn_off / REG_WIDTH;
        u8 off = insn_off % REG_WIDTH;

        dst_hi = reg_both(dst_gpr + 1);
        dst_lo = reg_both(dst_gpr);
        src_lo = reg_xfer(idx);

        /* The read length could involve as many as three registers. */
        if (size > REG_WIDTH - off) {
                /* Calculate the part in the second register. */
                len_lo = REG_WIDTH - off;
                len_mid = size - len_lo;

                /* Calculate the part in the third register. */
                if (size > 2 * REG_WIDTH - off)
                        len_mid = REG_WIDTH;
        }

        wrp_reg_subpart(nfp_prog, dst_lo, src_lo, len_lo, off);

        if (!len_mid) {
                wrp_zext(nfp_prog, meta, dst_gpr);
                return 0;
        }

        src_mid = reg_xfer(idx + 1);

        if (size <= REG_WIDTH) {
                wrp_reg_or_subpart(nfp_prog, dst_lo, src_mid, len_mid, len_lo);
                wrp_zext(nfp_prog, meta, dst_gpr);
        } else {
                swreg src_hi = reg_xfer(idx + 2);

                wrp_reg_or_subpart(nfp_prog, dst_lo, src_mid,
                                   REG_WIDTH - len_lo, len_lo);
                wrp_reg_subpart(nfp_prog, dst_hi, src_mid, len_lo,
                                REG_WIDTH - len_lo);
                wrp_reg_or_subpart(nfp_prog, dst_hi, src_hi, REG_WIDTH - len_lo,
                                   len_lo);
        }

        return 0;
}

static int
mem_ldx_data_from_pktcache_aligned(struct nfp_prog *nfp_prog,
                                   struct nfp_insn_meta *meta,
                                   unsigned int size)
{
        swreg dst_lo, dst_hi, src_lo;
        u8 dst_gpr, idx;

        idx = (meta->insn.off - meta->pkt_cache.range_start) / REG_WIDTH;
        dst_gpr = meta->insn.dst_reg * 2;
        dst_hi = reg_both(dst_gpr + 1);
        dst_lo = reg_both(dst_gpr);
        src_lo = reg_xfer(idx);

        if (size < REG_WIDTH) {
                wrp_reg_subpart(nfp_prog, dst_lo, src_lo, size, 0);
                wrp_zext(nfp_prog, meta, dst_gpr);
        } else if (size == REG_WIDTH) {
                wrp_mov(nfp_prog, dst_lo, src_lo);
                wrp_zext(nfp_prog, meta, dst_gpr);
        } else {
                swreg src_hi = reg_xfer(idx + 1);

                wrp_mov(nfp_prog, dst_lo, src_lo);
                wrp_mov(nfp_prog, dst_hi, src_hi);
        }

        return 0;
}

static int
mem_ldx_data_from_pktcache(struct nfp_prog *nfp_prog,
                           struct nfp_insn_meta *meta, unsigned int size)
{
        u8 off = meta->insn.off - meta->pkt_cache.range_start;

        if (IS_ALIGNED(off, REG_WIDTH))
                return mem_ldx_data_from_pktcache_aligned(nfp_prog, meta, size);

        return mem_ldx_data_from_pktcache_unaligned(nfp_prog, meta, size);
}

static int
mem_ldx(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
        unsigned int size)
{
        if (meta->ldst_gather_len)
                return nfp_cpp_memcpy(nfp_prog, meta);

        if (meta->ptr.type == PTR_TO_CTX) {
                if (nfp_prog->type == BPF_PROG_TYPE_XDP)
                        return mem_ldx_xdp(nfp_prog, meta, size);
                else
                        return mem_ldx_skb(nfp_prog, meta, size);
        }

        if (meta->ptr.type == PTR_TO_PACKET) {
                if (meta->pkt_cache.range_end) {
                        if (meta->pkt_cache.do_init)
                                mem_ldx_data_init_pktcache(nfp_prog, meta);

                        return mem_ldx_data_from_pktcache(nfp_prog, meta, size);
                } else {
                        return mem_ldx_data(nfp_prog, meta, size);
                }
        }

        if (meta->ptr.type == PTR_TO_STACK)
                return mem_ldx_stack(nfp_prog, meta, size,
                                     meta->ptr.off + meta->ptr.var_off.value);

        if (meta->ptr.type == PTR_TO_MAP_VALUE)
                return mem_ldx_emem(nfp_prog, meta, size);

        return -EOPNOTSUPP;
}

static int mem_ldx1(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_ldx(nfp_prog, meta, 1);
}

static int mem_ldx2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_ldx(nfp_prog, meta, 2);
}

static int mem_ldx4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_ldx(nfp_prog, meta, 4);
}

static int mem_ldx8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_ldx(nfp_prog, meta, 8);
}

static int
mem_st_data(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
            unsigned int size)
{
        u64 imm = meta->insn.imm; /* sign extend */
        swreg off_reg;

        off_reg = re_load_imm_any(nfp_prog, meta->insn.off, imm_b(nfp_prog));

        return data_st_host_order(nfp_prog, meta->insn.dst_reg * 2, off_reg,
                                  imm, size);
}

static int mem_st(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
                  unsigned int size)
{
        if (meta->ptr.type == PTR_TO_PACKET)
                return mem_st_data(nfp_prog, meta, size);

        return -EOPNOTSUPP;
}

static int mem_st1(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_st(nfp_prog, meta, 1);
}

static int mem_st2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_st(nfp_prog, meta, 2);
}

static int mem_st4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_st(nfp_prog, meta, 4);
}

static int mem_st8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_st(nfp_prog, meta, 8);
}

static int
mem_stx_data(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
             unsigned int size)
{
        swreg off_reg;

        off_reg = re_load_imm_any(nfp_prog, meta->insn.off, imm_b(nfp_prog));

        return data_stx_host_order(nfp_prog, meta->insn.dst_reg * 2, off_reg,
                                   meta->insn.src_reg * 2, size);
}

static int
mem_stx_stack(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
              unsigned int size, unsigned int ptr_off)
{
        return mem_op_stack(nfp_prog, meta, size, ptr_off,
                            meta->insn.src_reg * 2, meta->insn.dst_reg * 2,
                            false, wrp_lmem_store);
}

static int mem_stx_xdp(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        switch (meta->insn.off) {
        case offsetof(struct xdp_md, rx_queue_index):
                return nfp_queue_select(nfp_prog, meta);
        }

        WARN_ON_ONCE(1); /* verifier should have rejected bad accesses */
        return -EOPNOTSUPP;
}

static int
mem_stx(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
        unsigned int size)
{
        if (meta->ptr.type == PTR_TO_PACKET)
                return mem_stx_data(nfp_prog, meta, size);

        if (meta->ptr.type == PTR_TO_STACK)
                return mem_stx_stack(nfp_prog, meta, size,
                                     meta->ptr.off + meta->ptr.var_off.value);

        return -EOPNOTSUPP;
}

static int mem_stx1(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
        return mem_stx(nfp_prog, meta, 1);
}

static int mem_stx2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{