diff mbox series

[05/27] arc: TCG instruction generator and hand-definitions

Message ID 20210405143138.17016-6-cupertinomiranda@gmail.com
State New
Headers show
Series [01/27] arc: Add initial core cpu files | expand

Commit Message

Cupertino Miranda April 5, 2021, 2:31 p.m. UTC
From: Cupertino Miranda <cmiranda@synopsys.com>

Add the most generic parts of TCG constructions. It contains the
basic infrastructure for fundamental ARC features, such as
ZOL (zero overhead loops) and delay-slots.
Also includes hand crafted TCG for more intricate instructions, such
as vector instructions.

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
---
 target/arc/translate.c | 1530 ++++++++++++++++++++++++++++++++++++++++
 target/arc/translate.h |  168 +++++
 2 files changed, 1698 insertions(+)
 create mode 100644 target/arc/translate.c
 create mode 100644 target/arc/translate.h

Comments

Richard Henderson April 7, 2021, 3:52 a.m. UTC | #1
On 4/5/21 7:31 AM, cupertinomiranda@gmail.com wrote:
> From: Cupertino Miranda <cmiranda@synopsys.com>
> 
> Add the most generic parts of TCG constructions. It contains the
> basic infrastructure for fundamental ARC features, such as
> ZOL (zero overhead loops) and delay-slots.
> Also includes hand crafted TCG for more intricate instructions, such
> as vector instructions.
> 
> Signed-off-by: Shahab Vahedi <shahab@synopsys.com>

Procedure is that you also sign off on the patches you post.

> +#define REG(x)  (cpu_r[x])

Does this really provide any clarity to the code?

> +static inline bool use_goto_tb(const DisasContext *dc, target_ulong dest)

Drop all of the unnecessary inline markers.
The compiler will decide for itself just fine.

> +void gen_goto_tb(const DisasContext *ctx, int n, TCGv dest)
> +{
> +    tcg_gen_mov_tl(cpu_pc, dest);
> +    tcg_gen_andi_tl(cpu_pcl, dest, ~((target_ulong) 3));
> +    if (ctx->base.singlestep_enabled) {
> +        gen_helper_debug(cpu_env);
> +    } else {
> +        tcg_gen_exit_tb(NULL, 0);
> +    }
> +}

This doesn't use goto_tb, so perhaps a better name?

It also doesn't use tcg_gen_lookup_and_goto_ptr(), so it could be improved.

> +static void gen_gotoi_tb(const DisasContext *ctx, int n, target_ulong dest)
> +{
> +    if (use_goto_tb(ctx, dest)) {
> +        tcg_gen_goto_tb(n);
> +        tcg_gen_movi_tl(cpu_pc, dest);
> +        tcg_gen_movi_tl(cpu_pcl, dest & (~((target_ulong) 3)));
> +        tcg_gen_exit_tb(ctx->base.tb, n);
> +    } else {
> +        tcg_gen_movi_tl(cpu_pc, dest);
> +        tcg_gen_movi_tl(cpu_pcl, dest & (~((target_ulong) 3)));
> +        if (ctx->base.singlestep_enabled) {
> +            gen_helper_debug(cpu_env);
> +        }
> +        tcg_gen_exit_tb(NULL, 0);

Forgot the else, as above.  Also not using lookup.

> +    for (i = 0; i < 64; i++) {
> +        char name[16];
> +
> +        sprintf(name, "r[%d]", i);
> +        cpu_r[i] = tcg_global_mem_new(cpu_env,
> +                                      ARC_REG_OFFS(r[i]),
> +                                      strdup(name));

g_strdup_printf, and drop the local variable.

> +}
> +static void arc_tr_tb_start(DisasContextBase *dcbase, CPUState *cpu)

Mind the whitespace.

> +{
> +    /* place holder for now */
> +}
> +
> +static void arc_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
> +{
> +    DisasContext *dc = container_of(dcbase, DisasContext, base);
> +
> +
> +    tcg_gen_insn_start(dc->base.pc_next);

Similarly.

> +static int arc_gen_INVALID(const DisasContext *ctx)
> +{
> +    qemu_log_mask(LOG_UNIMP,
> +                  "invalid inst @:%08x\n", ctx->cpc);
> +    return DISAS_NEXT;
> +}

You need to generate an exception here.

> +    buffer[0] = cpu_lduw_code(ctx->env, ctx->cpc);

translator_lduw.

> +    length = arc_insn_length(buffer[0], cpu->family);
> +
> +    switch (length) {
> +    case 2:
> +        /* 16-bit instructions. */
> +        insn = (uint64_t) buffer[0];
> +        break;
> +    case 4:
> +        /* 32-bit instructions. */
> +        buffer[1] = cpu_lduw_code(ctx->env, ctx->cpc + 2);
> +        uint32_t buf = (buffer[0] << 16) | buffer[1];

Why use the array buffer[] and not a couple of scalars?

> +    if (ctx->insn.limm_p) {
> +        ctx->insn.limm = ARRANGE_ENDIAN(true,
> +                                        cpu_ldl_code(ctx->env,

translator_ldl

> +/*
> + * Throw "misaligned" exception if 'addr' is not 32-bit aligned.
> + * This check is done irrelevant of status32.AD bit.
> + */
> +static void check_addr_is_word_aligned(const DisasCtxt *ctx,
> +                                       TCGv addr)
> +{
> +    TCGLabel *l1 = gen_new_label();
> +    TCGv tmp = tcg_temp_local_new();
> +
> +    tcg_gen_andi_tl(tmp, addr, 0x3);
> +    tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, l1);
> +
> +    tcg_gen_mov_tl(cpu_efa, addr);
> +    tcg_gen_movi_tl(cpu_eret, ctx->cpc);
> +    tcg_gen_mov_tl(cpu_erbta, cpu_bta);
> +
> +    TCGv tcg_index = tcg_const_tl(EXCP_MISALIGNED);
> +    TCGv tcg_cause = tcg_const_tl(0x0);
> +    TCGv tcg_param = tcg_const_tl(0x0);
> +
> +    gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, tcg_param);
> +
> +    gen_set_label(l1);

So.. you shouldn't have to do anything like this.

As far as I can see, there's nothing special about enter/leave.  All memory ops 
are supposed to be aligned (with double-word ops treated as two word ops for 
alignment).

So you should be implementing TCGCPUOps.do_unaligned_access, and set 
TARGET_ALIGNED_ONLY in default-configs/.

Quite large this patch.  I'll get back to it later...


r~
Richard Henderson April 7, 2021, 4:47 p.m. UTC | #2
On 4/5/21 7:31 AM, cupertinomiranda@gmail.com wrote:
> +/*
> + * Function to add boiler plate code for conditional execution.
> + * It will add tcg_gen codes only if there is a condition to
> + * be checked (ctx->insn.cc != 0).
> + * Remember to pair it with gen_cc_epilogue(ctx) macro.
> + */
> +static void gen_cc_prologue(DisasCtxt *ctx)
> +{
> +    ctx->tmp_reg = tcg_temp_local_new();
> +    ctx->label = gen_new_label();

There's no point in creating these when insn.cc is false.

> +    if (ctx->insn.cc) {
> +        arc_gen_verifyCCFlag(ctx, ctx->tmp_reg);
> +        tcg_gen_brcondi_tl(TCG_COND_NE, ctx->tmp_reg, 1, ctx->label);

You don't need a local temp for tmp_reg.
You can create and free it here.

> +/*
> + * The finishing counter part of gen_cc_prologue. This is supposed
> + * to be put at the end of the function using it.
> + */
> +static void gen_cc_epilogue(const DisasCtxt *ctx)
> +{
> +    if (ctx->insn.cc) {
> +        gen_set_label(ctx->label);
> +    }
> +    tcg_temp_free(ctx->tmp_reg);
> +}

You do not need to keep it live til here.

> +/*
> + * Populates a 32-bit vector with repeating SHIMM:
> + *   vec32=(0000000000u6,0000000000u6)
> + *   vec32=(sssss12,sssss12)
> + * It's crucial that the s12 part of an encoding is in signed
> + * integer form while passed along in SHIMM, e.g:
> + *   s12 = -125 (0xf803) --> 0xfffff803
> + * Do not forget to free the returned TCGv_i32 when done!
> + */
> +static TCGv_i32 dup_shimm_to_i32(int16_t shimm)
> +{
> +    TCGv_i32 vec32 = tcg_temp_new_i32();
> +    int32_t val = shimm;
> +    val = ((val << 16) & 0xffff0000) | (val & 0xffff);
> +    tcg_gen_movi_i32(vec32, val);
> +    return vec32;
> +}

   return tcg_constant_i32(dup_const(MO_16, shimm));

> 
> +static TCGv_i64 dup_limm_to_i64(int32_t limm)
> +{
> +    TCGv_i64 vec64 = tcg_temp_new_i64();
> +    int64_t val = limm;
> +    val = (val << 32) | (val & 0xffffffff);
> +    tcg_gen_movi_i64(vec64, val);
> +    return vec64;
> +}

   return tcg_constant_i64(dup_const(MO_32, limm));

> +static TCGv_i64 quad_shimm_to_i64(int16_t shimm)
> +{
> +    TCGv_i64 vec64 = tcg_temp_new_i64();
> +    int64_t val = shimm;
> +    val = (val << 48) | ((val << 32) & 0x0000ffff00000000) |
> +          ((val << 16) & 0x00000000ffff0000) | (val & 0xffff);
> +    tcg_gen_movi_i64(vec64, val);
> +    return vec64;
> +}

   return tcg_constant_i64(dup_const(MO_16, shimm));

Note that, tcg_constant_* are hashed and need not be freed (but are silently 
accepted if you do).  However, you cannot assign to them.  If you really 
require a mutable temporary, use tcg_const_*.


> +static void gen_vec_op2h(const DisasCtxt *ctx,
> +                         void (*OP)(TCGv, TCGv, TCGv),
> +                         TCGv_i32 dest,
> +                         TCGv_i32 b32,
> +                         TCGv_i32 c32)
> +{
> +    TCGv_i32 t0, t1;
> +
> +    /* If no real register for result, then this a nop. Bail out! */
> +    if (!(ctx->insn.operands[0].type & ARC_OPERAND_IR)) {
> +        return;
> +    }
> +
> +    t0 = tcg_temp_new();
> +    tcg_gen_mov_i32(t0, b32);
> +    /*
> +     * If the last operand is a u6/s12, say 63, there is no "HI" in it.
> +     * Instead, it must be duplicated to form a pair; e.g.: (63, 63).
> +     */
> +    if (ctx->insn.operands[2].type & ARC_OPERAND_SHIMM) {
> +        t1 = dup_shimm_to_i32(ctx->insn.operands[2].value);
> +    } else {
> +        t1 = tcg_temp_new();
> +        tcg_gen_mov_i32(t1, c32);
> +    }
> +
> +    (*OP)(dest, t0, t1);
> +
> +    tcg_temp_free(t1);
> +    tcg_temp_free(t0);
> +}

Why are you copying b32 to a new temp?  Do you have callbacks that are not 
careful about overlap between dest, t0, t1, and assume that you have 
non-overlapping inputs?

If you don't require uniqueness, and use tcg_constant_* above, then you don't 
need to copy c32 into a new temp either, nor worry about conditionally freeing it.

> +static void gen_add16(TCGv_i32 dest, TCGv_i32 t0, TCGv_i32 t1)
> +{
> +    TCGv_i32 tmp = tcg_temp_new_i32();
> +    tcg_gen_xor_i32(tmp, t0, t1);
> +    tcg_gen_andi_i32(tmp, tmp, 0x8000);
> +    tcg_gen_andi_i32(t0, t0, ~0x8000);
> +    tcg_gen_andi_i32(t1, t1, ~0x8000);
> +    tcg_gen_add_i32(t0, t0, t1);
> +    tcg_gen_xor_i32(dest, t0, tmp);
> +    tcg_temp_free_i32(tmp);
> +}

I guess that answers my question of whether you're relying on new unique temps 
as inputs: yes.

> +static void arc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
> +{
> +    bool in_a_delayslot_instruction = false;
> +    DisasContext *dc = container_of(dcbase, DisasContext, base);
> +    CPUARCState *env = cpu->env_ptr;
> +
> +    /* TODO (issue #62): these must be removed */
> +    dc->zero = tcg_const_local_tl(0);
> +    dc->one  = tcg_const_local_tl(1);
> +
> +    if (env->stat.is_delay_slot_instruction == 1) {
> +        in_a_delayslot_instruction = true;
> +    }
> +
> +    dc->cpc = dc->base.pc_next;
> +    decode_opc(env, dc);
> +
> +    dc->base.pc_next = dc->npc;
> +    tcg_gen_movi_tl(cpu_npc, dc->npc);
> +
> +    if (in_a_delayslot_instruction == true) {
> +        dc->base.is_jmp = DISAS_NORETURN;
> +
> +        /* Post execution delayslot logic. */
> +        TCGLabel *DEf_not_set_label1 = gen_new_label();
> +        tcg_gen_brcondi_tl(TCG_COND_NE, cpu_DEf, 1, DEf_not_set_label1);
> +        tcg_gen_movi_tl(cpu_DEf, 0);
> +        gen_goto_tb(dc, 1, cpu_bta);
> +        gen_set_label(DEf_not_set_label1);
> +        env->stat.is_delay_slot_instruction = 0;

You may not examine or modify env directly during translate.
This absolutely will not work.


r~
diff mbox series

Patch

diff --git a/target/arc/translate.c b/target/arc/translate.c
new file mode 100644
index 0000000000..1712fcc9c3
--- /dev/null
+++ b/target/arc/translate.c
@@ -0,0 +1,1530 @@ 
+/*
+ * QEMU ARC CPU
+ *
+ * Copyright (c) 2020 Synppsys Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+
+#include "qemu/osdep.h"
+#include "translate.h"
+#include "qemu/qemu-print.h"
+#include "tcg/tcg-op-gvec.h"
+#include "target/arc/semfunc.h"
+#include "target/arc/arc-common.h"
+
+/* Globals */
+TCGv    cpu_S1f;
+TCGv    cpu_S2f;
+TCGv    cpu_CSf;
+
+TCGv    cpu_Ef;
+TCGv    cpu_IEf;
+TCGv    cpu_Vf;
+TCGv    cpu_Cf;
+TCGv    cpu_Nf;
+TCGv    cpu_Zf;
+TCGv    cpu_DEf;
+
+TCGv    cpu_is_delay_slot_instruction;
+
+TCGv    cpu_l1_Ef;
+TCGv    cpu_l1_Vf;
+TCGv    cpu_l1_Cf;
+TCGv    cpu_l1_Nf;
+TCGv    cpu_l1_Zf;
+TCGv    cpu_l1_DEf;
+
+TCGv    cpu_l2_Ef;
+TCGv    cpu_l2_Vf;
+TCGv    cpu_l2_Cf;
+TCGv    cpu_l2_Nf;
+TCGv    cpu_l2_Zf;
+TCGv    cpu_l2_DEf;
+
+TCGv    cpu_er_Ef;
+TCGv    cpu_er_Vf;
+TCGv    cpu_er_Cf;
+TCGv    cpu_er_Nf;
+TCGv    cpu_er_Zf;
+TCGv    cpu_er_DEf;
+
+TCGv    cpu_eret;
+TCGv    cpu_erbta;
+TCGv    cpu_ecr;
+TCGv    cpu_efa;
+
+TCGv    cpu_bta;
+TCGv    cpu_bta_l1;
+TCGv    cpu_bta_l2;
+
+TCGv    cpu_pc;
+/* replaced by AUX_REG array */
+TCGv    cpu_lps;
+TCGv    cpu_lpe;
+
+TCGv    cpu_r[64];
+
+TCGv    cpu_intvec;
+
+TCGv    cpu_lock_lf_var;
+
+/* NOTE: Pseudo register required for comparison with lp_end */
+TCGv    cpu_npc;
+
+/* Macros */
+
+#include "exec/gen-icount.h"
+#define REG(x)  (cpu_r[x])
+
+/* macro used to fix middle-endianess. */
+#define ARRANGE_ENDIAN(endianess, buf)                  \
+    ((endianess) ? ror32(buf, 16) : bswap32(buf))
+
+static inline bool use_goto_tb(const DisasContext *dc, target_ulong dest)
+{
+    if (unlikely(dc->base.singlestep_enabled)) {
+        return false;
+    }
+#ifndef CONFIG_USER_ONLY
+    return (dc->base.tb->pc & TARGET_PAGE_MASK) == (dest & TARGET_PAGE_MASK);
+#else
+    return true;
+#endif
+}
+
+void gen_goto_tb(const DisasContext *ctx, int n, TCGv dest)
+{
+    tcg_gen_mov_tl(cpu_pc, dest);
+    tcg_gen_andi_tl(cpu_pcl, dest, ~((target_ulong) 3));
+    if (ctx->base.singlestep_enabled) {
+        gen_helper_debug(cpu_env);
+    } else {
+        tcg_gen_exit_tb(NULL, 0);
+    }
+}
+
+static void gen_gotoi_tb(const DisasContext *ctx, int n, target_ulong dest)
+{
+    if (use_goto_tb(ctx, dest)) {
+        tcg_gen_goto_tb(n);
+        tcg_gen_movi_tl(cpu_pc, dest);
+        tcg_gen_movi_tl(cpu_pcl, dest & (~((target_ulong) 3)));
+        tcg_gen_exit_tb(ctx->base.tb, n);
+    } else {
+        tcg_gen_movi_tl(cpu_pc, dest);
+        tcg_gen_movi_tl(cpu_pcl, dest & (~((target_ulong) 3)));
+        if (ctx->base.singlestep_enabled) {
+            gen_helper_debug(cpu_env);
+        }
+        tcg_gen_exit_tb(NULL, 0);
+    }
+}
+
+void arc_translate_init(void)
+{
+    int i;
+#define ARC_REG_OFFS(x) offsetof(CPUARCState, x)
+
+#define NEW_ARC_REG(TCGV, FIELD) \
+        { &TCGV, offsetof(CPUARCState, FIELD), #FIELD },
+
+    static const struct { TCGv *ptr; int off; const char *name; } r32[] = {
+        NEW_ARC_REG(cpu_S1f, macmod.S1)
+        NEW_ARC_REG(cpu_S2f, macmod.S2)
+        NEW_ARC_REG(cpu_CSf, macmod.CS)
+
+        NEW_ARC_REG(cpu_Zf, stat.Zf)
+        NEW_ARC_REG(cpu_Nf, stat.Nf)
+        NEW_ARC_REG(cpu_Cf, stat.Cf)
+        NEW_ARC_REG(cpu_Vf, stat.Vf)
+        NEW_ARC_REG(cpu_DEf, stat.DEf)
+        NEW_ARC_REG(cpu_Ef, stat.Ef)
+        NEW_ARC_REG(cpu_IEf, stat.IEf)
+
+        NEW_ARC_REG(cpu_l1_Zf, stat_l1.Zf)
+        NEW_ARC_REG(cpu_l1_Nf, stat_l1.Nf)
+        NEW_ARC_REG(cpu_l1_Cf, stat_l1.Cf)
+        NEW_ARC_REG(cpu_l1_Vf, stat_l1.Vf)
+        NEW_ARC_REG(cpu_l1_DEf, stat_l1.DEf)
+
+        NEW_ARC_REG(cpu_er_Zf, stat_er.Zf)
+        NEW_ARC_REG(cpu_er_Nf, stat_er.Nf)
+        NEW_ARC_REG(cpu_er_Cf, stat_er.Cf)
+        NEW_ARC_REG(cpu_er_Vf, stat_er.Vf)
+        NEW_ARC_REG(cpu_er_DEf, stat_er.DEf)
+
+        NEW_ARC_REG(cpu_eret, eret)
+        NEW_ARC_REG(cpu_erbta, erbta)
+        NEW_ARC_REG(cpu_ecr, ecr)
+        NEW_ARC_REG(cpu_efa, efa)
+        NEW_ARC_REG(cpu_bta, bta)
+        NEW_ARC_REG(cpu_lps, lps)
+        NEW_ARC_REG(cpu_lpe, lpe)
+        NEW_ARC_REG(cpu_pc , pc)
+        NEW_ARC_REG(cpu_npc, npc)
+
+        NEW_ARC_REG(cpu_bta_l1, bta_l1)
+        NEW_ARC_REG(cpu_bta_l2, bta_l2)
+
+        NEW_ARC_REG(cpu_intvec, intvec)
+
+        NEW_ARC_REG(cpu_is_delay_slot_instruction,
+                    stat.is_delay_slot_instruction)
+
+        NEW_ARC_REG(cpu_lock_lf_var, lock_lf_var)
+    };
+
+
+    for (i = 0; i < ARRAY_SIZE(r32); ++i) {
+        *r32[i].ptr = tcg_global_mem_new(cpu_env, r32[i].off, r32[i].name);
+    }
+
+
+    for (i = 0; i < 64; i++) {
+        char name[16];
+
+        sprintf(name, "r[%d]", i);
+        cpu_r[i] = tcg_global_mem_new(cpu_env,
+                                      ARC_REG_OFFS(r[i]),
+                                      strdup(name));
+    }
+
+#undef ARC_REG_OFFS
+#undef NEW_ARC_REG
+}
+
+static void arc_tr_init_disas_context(DisasContextBase *dcbase,
+                                      CPUState *cs)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    dc->base.is_jmp = DISAS_NEXT;
+    dc->mem_idx = dc->base.tb->flags & 1;
+    dc->in_delay_slot = false;
+}
+static void arc_tr_tb_start(DisasContextBase *dcbase, CPUState *cpu)
+{
+    /* place holder for now */
+}
+
+static void arc_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+
+    tcg_gen_insn_start(dc->base.pc_next);
+    dc->cpc = dc->base.pc_next;
+
+    if (dc->base.num_insns == dc->base.max_insns &&
+        (dc->base.tb->cflags & CF_LAST_IO)) {
+        gen_io_start();
+    }
+}
+
+static bool arc_tr_breakpoint_check(DisasContextBase *dcbase, CPUState *cpu,
+                                    const CPUBreakpoint *bp)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    tcg_gen_movi_tl(cpu_pc, dc->cpc);
+    dc->base.is_jmp = DISAS_NORETURN;
+    gen_helper_debug(cpu_env);
+    dc->base.pc_next += 2;
+    return true;
+}
+
+static int arc_gen_INVALID(const DisasContext *ctx)
+{
+    qemu_log_mask(LOG_UNIMP,
+                  "invalid inst @:%08x\n", ctx->cpc);
+    return DISAS_NEXT;
+}
+
+/*
+ * Giving a CTX, decode it into an valid OPCODE_P if it
+ * exists. Returns TRUE if successfully.
+ */
+static bool read_and_decode_context(DisasContext *ctx,
+                                    const struct arc_opcode **opcode_p)
+{
+    uint16_t buffer[2];
+    uint8_t length;
+    uint64_t insn;
+    ARCCPU *cpu = env_archcpu(ctx->env);
+
+    /* Read the first 16 bits, figure it out what kind of instruction it is. */
+    buffer[0] = cpu_lduw_code(ctx->env, ctx->cpc);
+    length = arc_insn_length(buffer[0], cpu->family);
+
+    switch (length) {
+    case 2:
+        /* 16-bit instructions. */
+        insn = (uint64_t) buffer[0];
+        break;
+    case 4:
+        /* 32-bit instructions. */
+        buffer[1] = cpu_lduw_code(ctx->env, ctx->cpc + 2);
+        uint32_t buf = (buffer[0] << 16) | buffer[1];
+        insn = buf;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    /*
+     * Now, we have read the entire opcode, decode it and place the
+     * relevant info into opcode and ctx->insn.
+     */
+    *opcode_p = arc_find_format(&ctx->insn, insn, length, cpu->family);
+
+    if (*opcode_p == NULL) {
+        return false;
+    }
+
+    /*
+     * If the instruction requires long immediate, read the extra 4
+     * bytes and initialize the relevant fields.
+     */
+    if (ctx->insn.limm_p) {
+        ctx->insn.limm = ARRANGE_ENDIAN(true,
+                                        cpu_ldl_code(ctx->env,
+                                        ctx->cpc + length));
+        length += 4;
+    } else {
+        ctx->insn.limm = 0;
+    }
+
+    /* Update context. */
+    ctx->insn.len = length;
+    ctx->npc = ctx->cpc + length;
+    ctx->pcl = ctx->cpc & (~((target_ulong) 3));
+
+    return true;
+}
+
+/* Check if OPR is a register _and_ an odd numbered one. */
+static inline bool is_odd_numbered_register(const operand_t opr)
+{
+   return (opr.type & ARC_OPERAND_IR) && (opr.value & 1);
+}
+
+enum arc_opcode_map {
+    MAP_NONE = -1,
+#define SEMANTIC_FUNCTION(...)
+#define CONSTANT(...)
+#define MAPPING(MNEMONIC, NAME, NOPS, ...) MAP_##MNEMONIC##_##NAME,
+#include "target/arc/semfunc_mapping.def"
+#include "target/arc/extra_mapping.def"
+#undef MAPPING
+#undef CONSTANT
+#undef SEMANTIC_FUNCTION
+    /* Add some include to generated files */
+    MAP_LAST
+};
+
+const char number_of_ops_semfunc[MAP_LAST + 1] = {
+#define SEMANTIC_FUNCTION(...)
+#define CONSTANT(...)
+#define MAPPING(MNEMONIC, NAME, NOPS, ...) NOPS,
+#include "target/arc/semfunc_mapping.def"
+#include "target/arc/extra_mapping.def"
+#undef MAPPING
+#undef CONSTANT
+#undef SEMANTIC_FUNCTION
+    2
+};
+
+static enum arc_opcode_map arc_map_opcode(const struct arc_opcode *opcode)
+{
+#define SEMANTIC_FUNCTION(...)
+#define CONSTANT(...)
+#define MAPPING(MNEMONIC, NAME, ...)         \
+    if (strcmp(opcode->name, #MNEMONIC) == 0) \
+        return MAP_##MNEMONIC##_##NAME;
+#include "target/arc/semfunc_mapping.def"
+#include "target/arc/extra_mapping.def"
+#undef MAPPING
+#undef CONSTANT
+#undef SEMANTIC_FUNCTION
+
+    return MAP_NONE;
+}
+
+/* Code support for constant values coming from semantic function mapping. */
+struct constant_operands {
+    uint8_t operand_number;
+    uint32_t default_value;
+    struct constant_operands *next;
+};
+
+struct constant_operands *map_constant_operands[MAP_LAST];
+
+static void add_constant_operand(enum arc_opcode_map mapping,
+                                 uint8_t operand_number,
+                                 uint32_t value)
+{
+    struct constant_operands **t = &(map_constant_operands[mapping]);
+    while (*t != NULL) {
+        t = &((*t)->next);
+    }
+    *t = (struct constant_operands *) g_new(struct constant_operands, 1);
+
+    (*t)->operand_number = operand_number;
+    (*t)->default_value = value;
+    (*t)->next = NULL;
+}
+
+static struct constant_operands *
+constant_entry_for(enum arc_opcode_map mapping,
+                   uint8_t operand_number)
+{
+    struct constant_operands *t = map_constant_operands[mapping];
+    while (t != NULL) {
+        if (t->operand_number == operand_number) {
+            return t;
+        }
+        t = t->next;
+    }
+    return NULL;
+}
+
+static void init_constants(void)
+{
+#define SEMANTIC_FUNCTION(...)
+#define MAPPING(...)
+#define CONSTANT(NAME, MNEMONIC, OP_NUM, VALUE) \
+  add_constant_operand(MAP_##MNEMONIC##_##NAME, OP_NUM, VALUE);
+#include "target/arc/semfunc_mapping.def"
+#include "target/arc/extra_mapping.def"
+#undef MAPPING
+#undef CONSTANT
+#undef SEMANTIC_FUNCTION
+}
+
+static void arc_debug_opcode(const struct arc_opcode *opcode,
+                             DisasContext *ctx,
+                             const char *msg)
+{
+    qemu_log_mask(LOG_UNIMP,
+                  "%s for %s at pc=0x%08x\n",
+                  msg, opcode->name, ctx->cpc);
+}
+
+static TCGv arc_decode_operand(const struct arc_opcode *opcode,
+                               DisasContext *ctx,
+                               unsigned char nop,
+                               enum arc_opcode_map mapping)
+{
+    TCGv ret;
+
+    if (nop >= ctx->insn.n_ops) {
+        struct constant_operands *co = constant_entry_for(mapping, nop);
+        assert(co != NULL);
+        ret = tcg_const_local_tl(co->default_value);
+        return ret;
+    } else {
+        operand_t operand = ctx->insn.operands[nop];
+
+        if (operand.type & ARC_OPERAND_IR) {
+            ret = cpu_r[operand.value];
+            if (operand.value == 63) {
+                tcg_gen_movi_tl(cpu_pcl, ctx->pcl);
+            }
+        } else {
+            int64_t limm = operand.value;
+            if (operand.type & ARC_OPERAND_LIMM) {
+                limm = ctx->insn.limm;
+                tcg_gen_movi_tl(cpu_limm, limm);
+                ret = cpu_r[62];
+            } else {
+                ret = tcg_const_local_tl(limm);
+            }
+        }
+      }
+
+  return ret;
+}
+
+/* See translate.h. */
+void arc_gen_excp(const DisasCtxt *ctx,
+                  uint32_t index,
+                  uint32_t causecode,
+                  uint32_t param)
+{
+    TCGv tcg_index = tcg_const_tl(index);
+    TCGv tcg_cause = tcg_const_tl(causecode);
+    TCGv tcg_param = tcg_const_tl(param);
+
+    tcg_gen_movi_tl(cpu_pc, ctx->cpc);
+    tcg_gen_movi_tl(cpu_eret, ctx->cpc);
+    tcg_gen_movi_tl(cpu_erbta, ctx->npc);
+
+    gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, tcg_param);
+
+    tcg_temp_free(tcg_index);
+    tcg_temp_free(tcg_cause);
+    tcg_temp_free(tcg_param);
+}
+
+/* Wrapper around tcg_gen_exit_tb that handles single stepping */
+static void exit_tb(const DisasContext *ctx)
+{
+    if (ctx->base.singlestep_enabled) {
+        gen_helper_debug(cpu_env);
+    } else {
+        tcg_gen_exit_tb(NULL, 0);
+    }
+}
+
+/*
+ * throw "illegal instruction" exception if more than available
+ * registers are asked to be saved/restore.
+ */
+static bool check_enter_leave_nr_regs(const DisasCtxt *ctx,
+                                      uint8_t      regs)
+{
+    const uint8_t rgf_num_regs = env_archcpu(ctx->env)->cfg.rgf_num_regs;
+    if ((rgf_num_regs == 32 && regs > 14) ||
+        (rgf_num_regs == 16 && regs >  3)) {
+
+        TCGv tcg_index = tcg_const_tl(EXCP_INST_ERROR);
+        TCGv tcg_cause = tcg_const_tl(0);
+        TCGv tcg_param = tcg_const_tl(0);
+
+        tcg_gen_movi_tl(cpu_eret, ctx->cpc);
+        tcg_gen_movi_tl(cpu_erbta, ctx->npc);
+
+        gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, tcg_param);
+
+        tcg_temp_free(tcg_index);
+        tcg_temp_free(tcg_cause);
+        tcg_temp_free(tcg_param);
+        return false;
+    }
+    return true;
+}
+
+/*
+ * throw "illegal instruction sequence" exception if we are in a
+ * delay/execution slot.
+ */
+static bool check_delay_or_execution_slot(const DisasCtxt *ctx)
+{
+    if (ctx->in_delay_slot) {
+        TCGv tcg_index = tcg_const_tl(EXCP_INST_ERROR);
+        TCGv tcg_cause = tcg_const_tl(0x1);
+        TCGv tcg_param = tcg_const_tl(0x0);
+
+        tcg_gen_mov_tl(cpu_eret, cpu_pc);
+        tcg_gen_mov_tl(cpu_erbta, cpu_bta);
+
+        gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, tcg_param);
+
+        tcg_temp_free(tcg_index);
+        tcg_temp_free(tcg_cause);
+        tcg_temp_free(tcg_param);
+        return false;
+    }
+    return true;
+}
+
+/*
+ * Throw "misaligned" exception if 'addr' is not 32-bit aligned.
+ * This check is done irrelevant of status32.AD bit.
+ */
+static void check_addr_is_word_aligned(const DisasCtxt *ctx,
+                                       TCGv addr)
+{
+    TCGLabel *l1 = gen_new_label();
+    TCGv tmp = tcg_temp_local_new();
+
+    tcg_gen_andi_tl(tmp, addr, 0x3);
+    tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, l1);
+
+    tcg_gen_mov_tl(cpu_efa, addr);
+    tcg_gen_movi_tl(cpu_eret, ctx->cpc);
+    tcg_gen_mov_tl(cpu_erbta, cpu_bta);
+
+    TCGv tcg_index = tcg_const_tl(EXCP_MISALIGNED);
+    TCGv tcg_cause = tcg_const_tl(0x0);
+    TCGv tcg_param = tcg_const_tl(0x0);
+
+    gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, tcg_param);
+
+    gen_set_label(l1);
+
+    tcg_temp_free(tcg_index);
+    tcg_temp_free(tcg_cause);
+    tcg_temp_free(tcg_param);
+    tcg_temp_free(tmp);
+}
+
+
+
+/*
+ * enter_s instruction.
+ * after we are done, stack layout would be:
+ * ,- top -.
+ * | blink |
+ * | r13   |
+ * | r14   |
+ * | ...   |
+ * | r26   |
+ * | fp    |
+ * `-------'
+ */
+int arc_gen_ENTER(DisasContext *ctx)
+{
+    int ret = DISAS_NEXT;
+    uint32_t u6 = ctx->insn.operands[0].value;
+
+    if (!u6) {
+        return ret;
+    }
+
+    uint8_t regs       = u6 & 0x0f; /* u[3:0] determines registers to save */
+    bool    save_fp    = u6 & 0x10; /* u[4] indicates if fp must be saved  */
+    bool    save_blink = u6 & 0x20; /* u[5] indicates saving of blink      */
+    uint8_t stack_size = 4 * (regs + save_fp + save_blink);
+
+    /* number of regs to be saved must be sane */
+    if (!check_enter_leave_nr_regs(ctx, regs)) {
+        return ret;
+    }
+
+    /* this cannot be executed in a delay/execution slot */
+    if (!check_delay_or_execution_slot(ctx)) {
+        return ret;
+    }
+
+    TCGv temp_1 = tcg_temp_local_new();
+    TCGv temp_sp = tcg_temp_local_new();
+
+    /* stack must be a multiple of 4 (32 bit aligned) */
+    tcg_gen_subi_tl(temp_1, cpu_sp, stack_size);
+    check_addr_is_word_aligned(ctx, temp_1);
+
+    /*
+     * Backup SP. SP should only be written in the end of the execution to
+     * allow to correctly recover from exceptions the might happen in the
+     * middle of the instruction execution.
+     */
+    tcg_gen_mov_tl(temp_sp, cpu_sp);
+
+    if (save_fp) {
+        tcg_gen_subi_tl(temp_sp, temp_sp, 4);
+        tcg_gen_qemu_st_tl(cpu_fp, temp_sp, ctx->mem_idx, MO_UL);
+    }
+
+    for (uint8_t gpr = regs; gpr >= 1; --gpr) {
+        tcg_gen_subi_tl(temp_sp, temp_sp, 4);
+        tcg_gen_qemu_st_tl(cpu_r[13 + gpr - 1], temp_sp, ctx->mem_idx, MO_UL);
+    }
+
+    if (save_blink) {
+        tcg_gen_subi_tl(temp_sp, temp_sp, 4);
+        tcg_gen_qemu_st_tl(cpu_blink, temp_sp, ctx->mem_idx, MO_UL);
+    }
+
+    tcg_gen_mov_tl(cpu_sp, temp_sp);
+
+    /* now that sp has been allocated, shall we write it to fp? */
+    if (save_fp) {
+        tcg_gen_mov_tl(cpu_fp, cpu_sp);
+    }
+
+    tcg_temp_free(temp_sp);
+    tcg_temp_free(temp_1);
+
+    return ret;
+}
+
+/*
+ * helper for leave_s instruction.
+ * a stack layout of below is assumed:
+ * ,- top -.
+ * | blink |
+ * | r13   |
+ * | r14   |
+ * | ...   |
+ * | r26   |
+ * | fp    |
+ * `-------'
+ */
+int arc_gen_LEAVE(DisasContext *ctx)
+{
+    int ret = DISAS_NEXT;
+    uint32_t u7 = ctx->insn.operands[0].value;
+
+    /* nothing to do? then bye-bye! */
+    if (!u7) {
+        return ret;
+    }
+
+    uint8_t regs       = u7 & 0x0f; /* u[3:0] determines registers to save */
+    bool restore_fp    = u7 & 0x10; /* u[4] indicates if fp must be saved  */
+    bool restore_blink = u7 & 0x20; /* u[5] indicates saving of blink      */
+    bool jump_to_blink = u7 & 0x40; /* u[6] should we jump to blink?       */
+
+    /* number of regs to be saved must be sane */
+    if (!check_enter_leave_nr_regs(ctx, regs)) {
+        return ret;
+    }
+
+    /* this cannot be executed in a delay/execution slot */
+    if (!check_delay_or_execution_slot(ctx)) {
+        return ret;
+    }
+
+    TCGv temp_1 = tcg_temp_local_new();
+    /*
+     * stack must be a multiple of 4 (32 bit aligned). we must take into
+     * account if sp is going to use fp's value or not.
+     */
+    if (restore_fp) {
+        tcg_gen_mov_tl(temp_1, cpu_fp);
+    } else {
+        tcg_gen_mov_tl(temp_1, cpu_sp);
+    }
+    check_addr_is_word_aligned(ctx, temp_1);
+
+    TCGv temp_sp = tcg_temp_local_new();
+    /*
+     * if fp is in the picture, then first we have to use the current
+     * fp as the stack pointer for restoring.
+     */
+    if (restore_fp) {
+        tcg_gen_mov_tl(cpu_sp, cpu_fp);
+    }
+
+    tcg_gen_mov_tl(temp_sp, cpu_sp);
+
+    if (restore_blink) {
+        tcg_gen_qemu_ld_tl(cpu_blink, temp_sp, ctx->mem_idx, MO_UL);
+        tcg_gen_addi_tl(temp_sp, temp_sp, 4);
+    }
+
+    for (uint8_t gpr = 0; gpr < regs; ++gpr) {
+        tcg_gen_qemu_ld_tl(cpu_r[13 + gpr], temp_sp, ctx->mem_idx, MO_UL);
+        tcg_gen_addi_tl(temp_sp, temp_sp, 4);
+    }
+
+    if (restore_fp) {
+        tcg_gen_qemu_ld_tl(cpu_fp, temp_sp, ctx->mem_idx, MO_UL);
+        tcg_gen_addi_tl(temp_sp, temp_sp, 4);
+    }
+
+    tcg_gen_mov_tl(cpu_sp, temp_sp);
+
+    /* now that we are done, should we jump to blink? */
+    if (jump_to_blink) {
+        gen_goto_tb(ctx, 1, cpu_blink);
+        ret = DISAS_NORETURN;
+    }
+
+    tcg_temp_free(temp_sp);
+    tcg_temp_free(temp_1);
+
+    return ret;
+}
+
+/* SR tcg translator */
+int
+arc_gen_SR(DisasCtxt *ctx, TCGv src2, TCGv src1)
+{
+    int ret = DISAS_NEXT;
+
+    writeAuxReg(src2, src1);
+    return ret;
+}
+int
+arc_gen_SRL(DisasCtxt *ctx, TCGv src2, TCGv src1)
+{
+    int ret = DISAS_NEXT;
+
+    writeAuxReg(src2, src1);
+    return ret;
+}
+
+/* SYNC tcg translator */
+int
+arc_gen_SYNC(DisasCtxt *ctx)
+{
+    int ret = DISAS_NEXT;
+
+    syncReturnDisasUpdate();
+    return ret;
+}
+
+
+/*
+ * Function to add boiler plate code for conditional execution.
+ * It will add tcg_gen codes only if there is a condition to
+ * be checked (ctx->insn.cc != 0).
+ * Remember to pair it with gen_cc_epilogue(ctx) macro.
+ */
+static void gen_cc_prologue(DisasCtxt *ctx)
+{
+    ctx->tmp_reg = tcg_temp_local_new();
+    ctx->label = gen_new_label();
+    if (ctx->insn.cc) {
+        arc_gen_verifyCCFlag(ctx, ctx->tmp_reg);
+        tcg_gen_brcondi_tl(TCG_COND_NE, ctx->tmp_reg, 1, ctx->label);
+    }
+}
+
+/*
+ * The finishing counter part of gen_cc_prologue. This is supposed
+ * to be put at the end of the function using it.
+ */
+static void gen_cc_epilogue(const DisasCtxt *ctx)
+{
+    if (ctx->insn.cc) {
+        gen_set_label(ctx->label);
+    }
+    tcg_temp_free(ctx->tmp_reg);
+}
+
+/*
+ * Verifies if the destination operand (operand 0) is a register
+ * then it is an even numbered one. Else, an exception is put in
+ * the generated code and FALSE is returned.
+ */
+static bool verify_dest_reg_is_even(const DisasCtxt *ctx)
+{
+    if (is_odd_numbered_register(ctx->insn.operands[0])) {
+        arc_gen_excp(ctx, EXCP_INST_ERROR, 0, 0);
+        return false;
+    }
+    return true;
+}
+
+
+/* accumulator = b32 * c32 (signed multiplication). */
+int
+arc_gen_MPYD(DisasCtxt *ctx, TCGv_i32 dest,
+              TCGv_i32 b32, TCGv_i32 c32)
+{
+    if (verify_dest_reg_is_even(ctx)) {
+        gen_cc_prologue(ctx);
+        tcg_gen_muls2_i32(cpu_acclo, cpu_acchi, b32, c32);
+        if (ctx->insn.operands[0].type & ARC_OPERAND_IR) {
+            tcg_gen_mov_tl(arc_gen_next_reg(ctx, dest), cpu_acchi);
+            tcg_gen_mov_tl(dest, cpu_acclo);
+        }
+        if (ctx->insn.f) {
+            setNFlag(cpu_acchi);
+            tcg_gen_movi_tl(cpu_Vf, 0);
+        }
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+/* accumulator = b32 * c32 (unsigned multiplication). */
+int
+arc_gen_MPYDU(DisasCtxt *ctx, TCGv_i32 dest,
+              TCGv_i32 b32, TCGv_i32 c32)
+{
+    if (verify_dest_reg_is_even(ctx)) {
+        gen_cc_prologue(ctx);
+        tcg_gen_mulu2_i32(cpu_acclo, cpu_acchi, b32, c32);
+        if (ctx->insn.operands[0].type & ARC_OPERAND_IR) {
+            tcg_gen_mov_tl(arc_gen_next_reg(ctx, dest), cpu_acchi);
+            tcg_gen_mov_tl(dest, cpu_acclo);
+        }
+        if (ctx->insn.f) {
+            tcg_gen_movi_tl(cpu_Vf, 0);
+        }
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+/*
+ * Populates a 64-bit vector with register pair:
+ *   vec64=(REGn+1,REGn)=(REGn+1_hi,REGn+1_lo,REGn_hi,REGn_lo)
+ * REG must be refering to an even numbered register.
+ * Do not forget to free the returned TCGv_i64 when done!
+ */
+static TCGv_i64 pair_reg_to_i64(const DisasCtxt *ctx, TCGv_i32 reg)
+{
+    TCGv_i64 vec64 = tcg_temp_new_i64();
+    tcg_gen_concat_i32_i64(vec64, reg, arc_gen_next_reg(ctx, reg));
+    return vec64;
+}
+
+/*
+ * Populates a 32-bit vector with repeating SHIMM:
+ *   vec32=(0000000000u6,0000000000u6)
+ *   vec32=(sssss12,sssss12)
+ * It's crucial that the s12 part of an encoding is in signed
+ * integer form while passed along in SHIMM, e.g:
+ *   s12 = -125 (0xf803) --> 0xfffff803
+ * Do not forget to free the returned TCGv_i32 when done!
+ */
+static TCGv_i32 dup_shimm_to_i32(int16_t shimm)
+{
+    TCGv_i32 vec32 = tcg_temp_new_i32();
+    int32_t val = shimm;
+    val = ((val << 16) & 0xffff0000) | (val & 0xffff);
+    tcg_gen_movi_i32(vec32, val);
+    return vec32;
+}
+
+/*
+ * Populates a 64-bit vector with repeating LIMM:
+ *   vec64=(limm,limm)=(limm_hi,limm_lo,limm_hi,limm_lo)
+ * Do not forget to free the returned TCGv_i64 when done!
+ */
+static TCGv_i64 dup_limm_to_i64(int32_t limm)
+{
+    TCGv_i64 vec64 = tcg_temp_new_i64();
+    int64_t val = limm;
+    val = (val << 32) | (val & 0xffffffff);
+    tcg_gen_movi_i64(vec64, val);
+    return vec64;
+}
+
+/*
+ * Populates a 64-bit vector with four SHIMM (u6 or s12):
+ *   vec64=(0000000000u6,0000000000u6,0000000000u6,0000000000u6)
+ *   vec64=(sssss12,sssss12,sssss12,sssss12)
+ * It's crucial that the s12 part of an encoding is in signed
+ * integer form while passed along in SHIMM, e.g:
+ *   s12 = -125 (0xf803) --> 0xfffff803
+ * Do not forget to free the returned TCGv_i64 when done!
+ */
+static TCGv_i64 quad_shimm_to_i64(int16_t shimm)
+{
+    TCGv_i64 vec64 = tcg_temp_new_i64();
+    int64_t val = shimm;
+    val = (val << 48) | ((val << 32) & 0x0000ffff00000000) |
+          ((val << 16) & 0x00000000ffff0000) | (val & 0xffff);
+    tcg_gen_movi_i64(vec64, val);
+    return vec64;
+}
+
+/*
+ * gen_vec_op2 emits instructions to perform the desired operation,
+ * defined by OP, on the inputs (B32 and C32) and returns the
+ * result in DEST.
+ *
+ * vector size:     64-bit
+ * vector elements: 2
+ * element size:    32-bit
+ *
+ * (A1, A0) = (B1, B0) op (C1, C0)
+ */
+static void gen_vec_op2(const DisasCtxt *ctx,
+                        void (*OP)(TCGv_i64, TCGv_i64, TCGv_i64),
+                        TCGv_i32 dest,
+                        TCGv_i32 b32,
+                        TCGv_i32 c32)
+{
+    TCGv_i64 d64, b64, c64;
+
+    /* If no real register for result, then this a nop. Bail out! */
+    if (!(ctx->insn.operands[0].type & ARC_OPERAND_IR)) {
+        return;
+    }
+
+    /* Extend B32 to B64 based on its type: {reg, limm}. */
+    if (ctx->insn.operands[1].type & ARC_OPERAND_IR) {
+        b64 = pair_reg_to_i64(ctx, b32);
+    } else if (ctx->insn.operands[1].type & ARC_OPERAND_LIMM) {
+        b64 = dup_limm_to_i64(ctx->insn.limm);
+    } else {
+        g_assert_not_reached();
+    }
+    /* Extend C32 to C64 based on its type: {reg, limm, shimm}. */
+    if (ctx->insn.operands[2].type & ARC_OPERAND_IR) {
+        c64 = pair_reg_to_i64(ctx, c32);
+    } else if (ctx->insn.operands[2].type & ARC_OPERAND_LIMM) {
+        c64 = dup_limm_to_i64(ctx->insn.limm);
+    } else if (ctx->insn.operands[2].type & ARC_OPERAND_SHIMM) {
+        /* At this point SHIMM is extended like LIMM. */
+        c64 = dup_limm_to_i64(ctx->insn.operands[2].value);
+    } else {
+        g_assert_not_reached();
+    }
+    d64 = tcg_temp_new_i64();
+
+    (*OP)(d64, b64, c64);
+    tcg_gen_extrl_i64_i32(dest, d64);
+    tcg_gen_extrh_i64_i32(arc_gen_next_reg(ctx, dest), d64);
+
+    tcg_temp_free_i64(d64);
+    tcg_temp_free_i64(c64);
+    tcg_temp_free_i64(b64);
+    return;
+}
+
+/*
+ * gen_vec_op2h emits instructions to perform the desired operation,
+ * defined by OP, on the inputs (B32 and C32) and returns the
+ * result in DEST.
+ *
+ * vector size:     32-bit
+ * vector elements: 2
+ * element size:    16-bit
+ *
+ * (a1, a0) = (b1, b0) op (c1, c0)
+ */
+static void gen_vec_op2h(const DisasCtxt *ctx,
+                         void (*OP)(TCGv, TCGv, TCGv),
+                         TCGv_i32 dest,
+                         TCGv_i32 b32,
+                         TCGv_i32 c32)
+{
+    TCGv_i32 t0, t1;
+
+    /* If no real register for result, then this a nop. Bail out! */
+    if (!(ctx->insn.operands[0].type & ARC_OPERAND_IR)) {
+        return;
+    }
+
+    t0 = tcg_temp_new();
+    tcg_gen_mov_i32(t0, b32);
+    /*
+     * If the last operand is a u6/s12, say 63, there is no "HI" in it.
+     * Instead, it must be duplicated to form a pair; e.g.: (63, 63).
+     */
+    if (ctx->insn.operands[2].type & ARC_OPERAND_SHIMM) {
+        t1 = dup_shimm_to_i32(ctx->insn.operands[2].value);
+    } else {
+        t1 = tcg_temp_new();
+        tcg_gen_mov_i32(t1, c32);
+    }
+
+    (*OP)(dest, t0, t1);
+
+    tcg_temp_free(t1);
+    tcg_temp_free(t0);
+}
+
+
+/*
+ * gen_vec_op4h emits instructions to perform the desired operation,
+ * defined by OP, on the inputs (B32 and C32) and returns the
+ * result in DEST.
+ *
+ * vector size:     64-bit
+ * vector elements: 4
+ * element size:    16-bit
+ *
+ * (a3, a2, a1, a0) = (b3, b2, b1, b0) op (c3, c2, c1, c0)
+ */
+static void gen_vec_op4h(const DisasCtxt *ctx,
+                         void (*op)(TCGv_i64, TCGv_i64, TCGv_i64),
+                         TCGv_i32 dest,
+                         TCGv_i32 b32,
+                         TCGv_i32 c32)
+{
+    TCGv_i64 d64, b64, c64;
+
+    /* If no real register for result, then this a nop. Bail out! */
+    if (!(ctx->insn.operands[0].type & ARC_OPERAND_IR)) {
+        return;
+    }
+
+    /* Extend B32 to B64 based on its type: {reg, limm}. */
+    if (ctx->insn.operands[1].type & ARC_OPERAND_IR) {
+        b64 = pair_reg_to_i64(ctx, b32);
+    } else if (ctx->insn.operands[1].type & ARC_OPERAND_LIMM) {
+        b64 = dup_limm_to_i64(ctx->insn.limm);
+    } else {
+        g_assert_not_reached();
+    }
+    /* Extend C32 to C64 based on its type: {reg, limm, shimm}. */
+    if (ctx->insn.operands[2].type & ARC_OPERAND_IR) {
+        c64 = pair_reg_to_i64(ctx, c32);
+    } else if (ctx->insn.operands[2].type & ARC_OPERAND_LIMM) {
+        c64 = dup_limm_to_i64(ctx->insn.limm);
+    } else if (ctx->insn.operands[2].type & ARC_OPERAND_SHIMM) {
+        c64 = quad_shimm_to_i64(ctx->insn.operands[2].value);
+    } else {
+        g_assert_not_reached();
+    }
+    d64 = tcg_temp_new_i64();
+
+    (*op)(d64, b64, c64);
+    tcg_gen_extrl_i64_i32(dest, d64);
+    tcg_gen_extrh_i64_i32(arc_gen_next_reg(ctx, dest), d64);
+
+    tcg_temp_free_i64(d64);
+    tcg_temp_free_i64(c64);
+    tcg_temp_free_i64(b64);
+    return;
+}
+
+/*
+ * To use a 32-bit adder to sum two 16-bit numbers:
+ * 1) Mask out the 16th bit in both operands to cause no carry.
+ * 2) Add the numbers.
+ * 3) Put back the 16th bit sum: T0[15] ^ T1[15] ^ CARRY[14]
+ *    (ignoring the possible carry generated)
+ * T0 and T1 values will change. Use temporary ones.
+ */
+static void gen_add16(TCGv_i32 dest, TCGv_i32 t0, TCGv_i32 t1)
+{
+    TCGv_i32 tmp = tcg_temp_new_i32();
+    tcg_gen_xor_i32(tmp, t0, t1);
+    tcg_gen_andi_i32(tmp, tmp, 0x8000);
+    tcg_gen_andi_i32(t0, t0, ~0x8000);
+    tcg_gen_andi_i32(t1, t1, ~0x8000);
+    tcg_gen_add_i32(t0, t0, t1);
+    tcg_gen_xor_i32(dest, t0, tmp);
+    tcg_temp_free_i32(tmp);
+}
+
+/*
+ * To use a 32-bit subtracter to subtract two 16-bit numbers:
+ * 0) Record how T0[15]-T1[15] would result without other bits.
+ * 1) Make the 16th bit for the first operand 1 and the second
+ *    operand 0. This combination of (1 - 0) will absorb any
+ *    possible borrow that may come from the 15th bit.
+ * 2) Subtract the numbers.
+ * 3) Correct the 16th bit result (1 - 0 - B):
+ *    If the 16th bit is 1 --> no borrow was asked.
+ *    If the 16th bit is 0 --> a  borrow was asked.
+ *    and if a borrow was asked, the result of step 0 must be
+ *    inverted (0 -> 1 and 1 -> 0). If not, the result of step
+ *    0 can be used readily:
+ *     STEP2[15] | T0[15]-T1[15] | DEST[15]
+ *     ----------+---------------+---------
+ *         0     |       0       |    1
+ *         0     |       1       |    0
+ *         1     |       0       |    0
+ *         1     |       1       |    1
+ *    This is a truth table for XNOR(a,b):
+ *      NOT(XOR(a,b))=XOR(XOR(a,b),1)
+ * This approach might seem pedantic, but it generates one less
+ * instruction than the obvious mask-and-sub approach and requires
+ * two less TCG variables.
+ * T0 and T1 values will change. Use temporary ones.
+ */
+static void gen_sub16(TCGv_i32 dest, TCGv_i32 t0, TCGv_i32 t1)
+{
+    TCGv_i32 tmp = tcg_temp_new_i32();
+    tcg_gen_xor_i32(tmp, t0, t1);          /* step 0 */
+    tcg_gen_andi_i32(tmp, tmp, 0x8000);    /* step 0 */
+    tcg_gen_ori_i32(t0, t0, 0x8000);       /* step 1 */
+    tcg_gen_andi_i32(t1, t1, ~0x8000);     /* step 1 */
+    tcg_gen_sub_i32(t0, t0, t1);           /* step 2 */
+    tcg_gen_xor_i32(dest, t0, tmp);        /* step 3 */
+    tcg_gen_xori_i32(dest, dest, 0x8000);  /* step 3 */
+    tcg_temp_free_i32(tmp);
+}
+
+/*
+ * Going through every operand, if any of those is a register
+ * it is verified to be an even numbered register. Else, an
+ * exception is put in the generated code and FALSE is returned.
+ */
+static bool verify_all_regs_are_even(const DisasCtxt *ctx)
+{
+    for (int nop = 0; nop < ctx->insn.n_ops; ++nop) {
+        if (is_odd_numbered_register(ctx->insn.operands[nop])) {
+            arc_gen_excp(ctx, EXCP_INST_ERROR, 0, 0);
+            return false;
+        }
+    }
+    return true;
+}
+
+
+int
+arc_gen_VADD2(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    if (verify_all_regs_are_even(ctx)) {
+        gen_cc_prologue(ctx);
+        gen_vec_op2(ctx, tcg_gen_vec_add32_i64, dest, b, c);
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_VADD2H(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    gen_cc_prologue(ctx);
+    gen_vec_op2h(ctx, gen_add16, dest, b, c);
+    gen_cc_epilogue(ctx);
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_VADD4H(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    if (verify_all_regs_are_even(ctx)) {
+        gen_cc_prologue(ctx);
+        gen_vec_op4h(ctx, tcg_gen_vec_add16_i64, dest, b, c);
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_VSUB2(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    if (verify_all_regs_are_even(ctx)) {
+        gen_cc_prologue(ctx);
+        gen_vec_op2(ctx, tcg_gen_vec_sub32_i64, dest, b, c);
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_VSUB2H(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    gen_cc_prologue(ctx);
+    gen_vec_op2h(ctx, gen_sub16, dest, b, c);
+    gen_cc_epilogue(ctx);
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_VSUB4H(DisasCtxt *ctx, TCGv dest, TCGv_i32 b, TCGv_i32 c)
+{
+    if (verify_all_regs_are_even(ctx)) {
+        gen_cc_prologue(ctx);
+        gen_vec_op4h(ctx, tcg_gen_vec_sub16_i64, dest, b, c);
+        gen_cc_epilogue(ctx);
+    }
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_SWI(DisasCtxt *ctx, TCGv a)
+{
+    TCGv tcg_index = tcg_const_tl(EXCP_SWI);
+    TCGv tcg_cause = tcg_const_tl(0);
+
+    tcg_gen_movi_tl(cpu_pc, ctx->cpc);
+    tcg_gen_movi_tl(cpu_eret, ctx->cpc);
+    tcg_gen_movi_tl(cpu_erbta, ctx->npc);
+
+    gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, a);
+
+    tcg_temp_free(tcg_index);
+    tcg_temp_free(tcg_cause);
+    return DISAS_NEXT;
+}
+int
+arc_gen_TRAP(DisasCtxt *ctx, TCGv a)
+{
+    TCGv tcg_index = tcg_const_tl(EXCP_TRAP);
+    TCGv tcg_cause = tcg_const_tl(0);
+
+    tcg_gen_movi_tl(cpu_pc, ctx->cpc);
+    tcg_gen_movi_tl(cpu_eret, ctx->npc);
+    tcg_gen_mov_tl(cpu_erbta, cpu_bta);
+
+    gen_helper_raise_exception(cpu_env, tcg_index, tcg_cause, a);
+
+    tcg_temp_free(tcg_index);
+    tcg_temp_free(tcg_cause);
+
+    return DISAS_NORETURN;
+}
+int
+arc_gen_RTIE(DisasCtxt *ctx)
+{
+    tcg_gen_movi_tl(cpu_pc, ctx->cpc);
+    gen_helper_rtie(cpu_env);
+    tcg_gen_mov_tl(cpu_pc, cpu_pcl);
+    exit_tb(ctx); /* no chaining */
+    return DISAS_NORETURN;
+}
+
+/* Generate sleep insn. */
+int
+arc_gen_SLEEP(DisasCtxt *ctx, TCGv a)
+{
+    uint32_t param = 0;
+
+    if (ctx->insn.operands[0].type & ARC_OPERAND_IR) {
+        TCGv tmp3 = tcg_temp_local_new();
+        TCGLabel *done_L = gen_new_label();
+
+        tcg_gen_andi_tl(tmp3, a, 0x10);
+        tcg_gen_brcondi_tl(TCG_COND_NE, tmp3, 0x10, done_L);
+        tcg_gen_andi_tl(cpu_Ef, a, 0x0f);
+        tcg_gen_movi_tl(cpu_IEf, 1);
+        gen_set_label(done_L);
+
+        tcg_temp_free(tmp3);
+    } else {
+        param = ctx->insn.operands[0].value;
+        if (param & 0x10) {
+            tcg_gen_movi_tl(cpu_IEf, 1);
+            tcg_gen_movi_tl(cpu_Ef, param & 0x0f);
+        }
+    }
+    /* FIXME: setup debug registers as well. */
+
+    TCGv npc = tcg_temp_local_new();
+    tcg_gen_movi_tl(npc, ctx->npc);
+    gen_helper_halt(cpu_env, npc);
+    tcg_temp_free(npc);
+    return DISAS_NEXT;
+}
+
+/* Given a CTX, generate the relevant TCG code for the given opcode. */
+static int arc_decode(DisasContext *ctx, const struct arc_opcode *opcode)
+{
+    int ret = DISAS_NEXT;
+    enum arc_opcode_map mapping;
+    static bool initialized;
+
+    if (initialized == false) {
+        init_constants();
+        initialized = true;
+    }
+
+    /* Do the mapping. */
+    mapping = arc_map_opcode(opcode);
+    if (mapping != MAP_NONE) {
+        TCGv ops[10];
+        int i;
+        for (i = 0; i < number_of_ops_semfunc[mapping]; i++) {
+            ops[i] = arc_decode_operand(opcode, ctx, i, mapping);
+        }
+
+        /*
+         * Store some elements statically to implement less dynamic
+         * features of instructions.  Started by the need to keep a
+         * static reference to LP_START and LP_END.
+         */
+
+#define SEMANTIC_FUNCTION_CALL_0(NAME, A)       \
+            arc_gen_##NAME(ctx);
+#define SEMANTIC_FUNCTION_CALL_1(NAME, A)       \
+            arc_gen_##NAME(ctx, ops[A]);
+#define SEMANTIC_FUNCTION_CALL_2(NAME, A, B)            \
+            arc_gen_##NAME(ctx, ops[A], ops[B]);
+#define SEMANTIC_FUNCTION_CALL_3(NAME, A, B, C)                 \
+            arc_gen_##NAME(ctx, ops[A], ops[B], ops[C]);
+#define SEMANTIC_FUNCTION_CALL_4(NAME, A, B, C, D)                      \
+            arc_gen_##NAME(ctx, ops[A], ops[B], ops[C], ops[D]);
+
+#define SEMANTIC_FUNCTION(...)
+#define CONSTANT(...)
+#define MAPPING(MNEMONIC, NAME, NOPS, ...)                              \
+            case MAP_##MNEMONIC##_##NAME:                               \
+                ret = SEMANTIC_FUNCTION_CALL_##NOPS(NAME, __VA_ARGS__); \
+                break;
+        switch (mapping) {
+#include "target/arc/semfunc_mapping.def"
+#include "target/arc/extra_mapping.def"
+
+        default:
+            arc_debug_opcode(opcode, ctx, "No handle for map opcode");
+            g_assert(!"Semantic not handled: Use -d unimp to list it.");
+        }
+#undef MAPPING
+#undef CONSTANT
+#undef SEMANTIC_FUNCTION
+#undef SEMANTIC_FUNCTION_CALL_0
+#undef SEMANTIC_FUNCTION_CALL_1
+#undef SEMANTIC_FUNCTION_CALL_2
+#undef SEMANTIC_FUNCTION_CALL_3
+
+        for (i = 0; i < number_of_ops_semfunc[mapping]; i++) {
+            operand_t operand = ctx->insn.operands[i];
+            if (!(operand.type & ARC_OPERAND_LIMM) &&
+                !(operand.type & ARC_OPERAND_IR)) {
+                tcg_temp_free(ops[i]);
+            }
+        }
+
+    } else {
+        arc_debug_opcode(opcode, ctx, "No mapping for opcode");
+        g_assert(!"Semantic not found: Use -d unimp to list it.");
+    }
+
+    return ret;
+}
+
+void decode_opc(CPUARCState *env, DisasContext *ctx)
+{
+    ctx->env = env;
+
+    env->enabled_interrupts = false;
+
+    const struct arc_opcode *opcode = NULL;
+    if (!read_and_decode_context(ctx, &opcode)) {
+        ctx->base.is_jmp = arc_gen_INVALID(ctx);
+        return;
+    }
+
+    ctx->base.is_jmp = arc_decode(ctx, opcode);
+
+    TCGv npc = tcg_const_local_tl(ctx->npc);
+    gen_helper_zol_verify(cpu_env, npc);
+    tcg_temp_free(npc);
+
+    env->enabled_interrupts = true;
+}
+
+static void arc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
+{
+    bool in_a_delayslot_instruction = false;
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+    CPUARCState *env = cpu->env_ptr;
+
+    /* TODO (issue #62): these must be removed */
+    dc->zero = tcg_const_local_tl(0);
+    dc->one  = tcg_const_local_tl(1);
+
+    if (env->stat.is_delay_slot_instruction == 1) {
+        in_a_delayslot_instruction = true;
+    }
+
+    dc->cpc = dc->base.pc_next;
+    decode_opc(env, dc);
+
+    dc->base.pc_next = dc->npc;
+    tcg_gen_movi_tl(cpu_npc, dc->npc);
+
+    if (in_a_delayslot_instruction == true) {
+        dc->base.is_jmp = DISAS_NORETURN;
+
+        /* Post execution delayslot logic. */
+        TCGLabel *DEf_not_set_label1 = gen_new_label();
+        tcg_gen_brcondi_tl(TCG_COND_NE, cpu_DEf, 1, DEf_not_set_label1);
+        tcg_gen_movi_tl(cpu_DEf, 0);
+        gen_goto_tb(dc, 1, cpu_bta);
+        gen_set_label(DEf_not_set_label1);
+        env->stat.is_delay_slot_instruction = 0;
+    }
+
+    if (dc->base.is_jmp == DISAS_NORETURN) {
+        gen_gotoi_tb(dc, 0, dc->npc);
+    } else if (dc->base.is_jmp == DISAS_NEXT) {
+        target_ulong page_start;
+
+        page_start = dc->base.pc_first & TARGET_PAGE_MASK;
+        if (dc->base.pc_next - page_start >= TARGET_PAGE_SIZE) {
+            dc->base.is_jmp = DISAS_TOO_MANY;
+        }
+    }
+
+    /* TODO (issue #62): these must be removed. */
+    tcg_temp_free(dc->zero);
+    tcg_temp_free(dc->one);
+
+    /* verify if there is any TCG temporaries leakge */
+    translator_loop_temp_check(dcbase);
+}
+
+static void arc_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    switch (dc->base.is_jmp) {
+    case DISAS_TOO_MANY:
+    case DISAS_UPDATE:
+        gen_gotoi_tb(dc, 0, dc->base.pc_next);
+        break;
+    case DISAS_BRANCH_IN_DELAYSLOT:
+    case DISAS_NORETURN:
+        break;
+    default:
+         g_assert_not_reached();
+    }
+
+    if (dc->base.num_insns == dc->base.max_insns &&
+        (dc->base.tb->cflags & CF_LAST_IO)) {
+        gen_io_end();
+    }
+}
+
+static void arc_tr_disas_log(const DisasContextBase *dcbase, CPUState *cpu)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    qemu_log("IN: %s\n", lookup_symbol(dc->base.pc_first));
+    log_target_disas(cpu, dc->base.pc_first, dc->base.tb->size);
+}
+
+
+static const TranslatorOps arc_translator_ops = {
+    .init_disas_context = arc_tr_init_disas_context,
+    .tb_start           = arc_tr_tb_start,
+    .insn_start         = arc_tr_insn_start,
+    .breakpoint_check   = arc_tr_breakpoint_check,
+    .translate_insn     = arc_tr_translate_insn,
+    .tb_stop            = arc_tr_tb_stop,
+    .disas_log          = arc_tr_disas_log,
+};
+
+/* generate intermediate code for basic block 'tb'. */
+void gen_intermediate_code(CPUState *cpu,
+                           TranslationBlock *tb,
+                           int max_insns)
+{
+    DisasContext dc;
+    const TranslatorOps *ops = &arc_translator_ops;
+    translator_loop(ops, &dc.base, cpu, tb, max_insns);
+}
+
+void restore_state_to_opc(CPUARCState *env,
+                          TranslationBlock *tb,
+                          target_ulong *data)
+{
+    env->pc = data[0];
+}
+
+void arc_cpu_dump_state(CPUState *cs, FILE *f, int flags)
+{
+    ARCCPU *cpu = ARC_CPU(cs);
+    CPUARCState *env = &cpu->env;
+    int i;
+
+
+    qemu_fprintf(f,
+                 "STATUS:  [ %c %c %c %c %c %c %s %s %s %s %s %s %c]\n",
+                 GET_STATUS_BIT(env->stat, Lf)  ? 'L' : '-',
+                 env->stat.Zf ? 'Z' : '-',
+                 env->stat.Nf ? 'N' : '-',
+                 env->stat.Cf ? 'C' : '-',
+                 env->stat.Vf ? 'V' : '-',
+                 GET_STATUS_BIT(env->stat, Uf)  ? 'U' : '-',
+                 env->stat.DEf ? "DE" : "--",
+                 GET_STATUS_BIT(env->stat, AEf) ? "AE" : "--",
+                 env->stat.Ef  ? "E" : "--",
+                 GET_STATUS_BIT(env->stat, DZf) ? "DZ" : "--",
+                 GET_STATUS_BIT(env->stat, SCf) ? "SC" : "--",
+                 env->stat.IEf ? "IE" : "--",
+                 GET_STATUS_BIT(env->stat, Hf)  ? 'H' : '-'
+                 );
+
+    qemu_fprintf(f, "\n");
+    for (i = 0; i < ARRAY_SIZE(env->r); i++) {
+        qemu_fprintf(f, "R[%02d]:  " TARGET_FMT_lx "   ", i, env->r[i]);
+
+        if ((i % 8) == 7) {
+            qemu_fprintf(f, "\n");
+        }
+    }
+}
+
+
+/*-*-indent-tabs-mode:nil;tab-width:4;indent-line-function:'insert-tab'-*-*/
+/* vim: set ts=4 sw=4 et: */
diff --git a/target/arc/translate.h b/target/arc/translate.h
new file mode 100644
index 0000000000..3986c2298e
--- /dev/null
+++ b/target/arc/translate.h
@@ -0,0 +1,168 @@ 
+/*
+ * QEMU ARC CPU
+ *
+ * Copyright (c) 2020 Synppsys Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+
+#ifndef ARC_TRANSLATE_H_
+#define ARC_TRANSLATE_H_
+
+
+#include "arc-common.h"
+
+#include "tcg/tcg.h"
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "disas/disas.h"
+#include "tcg/tcg-op.h"
+#include "exec/cpu_ldst.h"
+
+#include "exec/helper-proto.h"
+#include "exec/helper-gen.h"
+#include "exec/log.h"
+
+#include "exec/translator.h"
+
+/* signaling the end of translation block */
+#define DISAS_UPDATE        DISAS_TARGET_0
+#define DISAS_BRANCH_IN_DELAYSLOT DISAS_TARGET_1
+
+typedef struct DisasContext {
+    DisasContextBase base;
+
+    uint32_t cpc;   /*  current pc      */
+    uint32_t npc;   /*  next pc         */
+    uint32_t dpc;   /*  next next pc    */
+    uint32_t pcl;
+    uint32_t lpe;
+    uint32_t lps;
+
+    unsigned ds;    /*  we are within ds*/
+
+    /* TODO (issue #62): these must be removed */
+    TCGv     zero;  /*  0x00000000      */
+    TCGv     one;   /*  0x00000001      */
+
+    insn_t insn;
+
+    CPUARCState *env;
+
+    uint16_t buffer[2];
+    uint8_t  mem_idx;
+
+    bool in_delay_slot;
+
+    TCGv     tmp_reg;
+    TCGLabel *label;
+
+} DisasContext;
+
+
+#define cpu_gp     (cpu_r[26])
+#define cpu_fp     (cpu_r[27])
+#define cpu_sp     (cpu_r[28])
+#define cpu_ilink1 (cpu_r[29])
+#define cpu_ilink2 (cpu_r[30])
+#define cpu_blink  (cpu_r[31])
+#define cpu_acclo  (cpu_r[58])
+#define cpu_acchi  (cpu_r[59])
+#define cpu_lpc    (cpu_r[60])
+#define cpu_pcl    (cpu_r[63])
+#define cpu_limm   (cpu_r[62])
+
+extern TCGv     cpu_S1f;
+extern TCGv     cpu_S2f;
+extern TCGv     cpu_CSf;
+
+extern TCGv     cpu_Ef;
+extern TCGv     cpu_IEf;
+extern TCGv     cpu_Vf;
+extern TCGv     cpu_Cf;
+extern TCGv     cpu_Nf;
+extern TCGv     cpu_Zf;
+extern TCGv     cpu_DEf;
+
+extern TCGv     cpu_is_delay_slot_instruction;
+
+extern TCGv     cpu_l1_Ef;
+extern TCGv     cpu_l1_Vf;
+extern TCGv     cpu_l1_Cf;
+extern TCGv     cpu_l1_Nf;
+extern TCGv     cpu_l1_Zf;
+extern TCGv     cpu_l1_DEf;
+
+extern TCGv     cpu_l2_Ef;
+extern TCGv     cpu_l2_Vf;
+extern TCGv     cpu_l2_Cf;
+extern TCGv     cpu_l2_Nf;
+extern TCGv     cpu_l2_Zf;
+extern TCGv     cpu_l2_DEf;
+
+extern TCGv     cpu_er_Ef;
+extern TCGv     cpu_er_Vf;
+extern TCGv     cpu_er_Cf;
+extern TCGv     cpu_er_Nf;
+extern TCGv     cpu_er_Zf;
+extern TCGv     cpu_er_DEf;
+
+extern TCGv     cpu_eret;
+extern TCGv     cpu_erbta;
+extern TCGv     cpu_ecr;
+extern TCGv     cpu_efa;
+
+extern TCGv     cpu_pc;
+extern TCGv     cpu_lps;
+extern TCGv     cpu_lpe;
+
+extern TCGv     cpu_npc;
+
+extern TCGv     cpu_bta;
+extern TCGv     cpu_bta_l1;
+extern TCGv     cpu_bta_l2;
+
+extern TCGv     cpu_r[64];
+
+extern TCGv     cpu_intvec;
+
+extern TCGv     cpu_lock_lf_var;
+
+extern TCGv     cpu_exception_delay_slot_address;
+
+
+/* TODO: Remove DisasCtxt.  */
+typedef struct DisasContext DisasCtxt;
+
+void gen_goto_tb(const DisasContext *ctx, int n, TCGv dest);
+
+void decode_opc(CPUARCState *env, DisasContext *ctx);
+
+/*
+ * Helper function to glue "rasing an exception" in the generated TCGs.
+ *
+ * ctx:         Disassembling context
+ * index:       ECR's index field
+ * causecode:   ECR's cause code filed
+ * param:       ECR's parameter field
+ */
+void arc_gen_excp(const DisasCtxt *ctx, uint32_t index,
+                  uint32_t causecode, uint32_t param);
+
+#endif
+
+
+/*-*-indent-tabs-mode:nil;tab-width:4;indent-line-function:'insert-tab'-*-*/
+/* vim: set ts=4 sw=4 et: */