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From: Michael Rolnik <mrolnik@gmail.com>
To: qemu-devel@nongnu.org
Cc: thuth@redhat.com, dovgaluk@ispras.ru,
	richard.henderson@linaro.org, Michael Rolnik <mrolnik@gmail.com>,
	imammedo@redhat.com, philmd@redhat.com
Subject: [Qemu-devel] [PATCH v29 4/8] target/avr: Add instruction translation
Date: Sat, 24 Aug 2019 21:46:31 +0300
Message-ID: <20190824184635.34192-5-mrolnik@gmail.com> (raw)
In-Reply-To: <20190824184635.34192-1-mrolnik@gmail.com>

This includes:
- TCG translations for each instruction

Signed-off-by: Michael Rolnik <mrolnik@gmail.com>
---
 target/avr/translate.c | 2888 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 2888 insertions(+)
 create mode 100644 target/avr/translate.c

diff --git a/target/avr/translate.c b/target/avr/translate.c
new file mode 100644
index 0000000000..42cb4a690c
--- /dev/null
+++ b/target/avr/translate.c
@@ -0,0 +1,2888 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2019 Michael Rolnik
+ *
+ * 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 "qemu/qemu-print.h"
+#include "tcg/tcg.h"
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "disas/disas.h"
+#include "tcg-op.h"
+#include "exec/cpu_ldst.h"
+#include "exec/helper-proto.h"
+#include "exec/helper-gen.h"
+#include "exec/log.h"
+#include "exec/gdbstub.h"
+#include "exec/translator.h"
+
+/*
+ *  Define if you want a BREAK instruction translated to a breakpoint
+ *  Active debugging connection is assumed
+ *  This is for
+ *  https://github.com/seharris/qemu-avr-tests/tree/master/instruction-tests
+ *  tests
+ */
+#undef BREAKPOINT_ON_BREAK
+
+static TCGv cpu_pc;
+
+static TCGv cpu_Cf;
+static TCGv cpu_Zf;
+static TCGv cpu_Nf;
+static TCGv cpu_Vf;
+static TCGv cpu_Sf;
+static TCGv cpu_Hf;
+static TCGv cpu_Tf;
+static TCGv cpu_If;
+
+static TCGv cpu_rampD;
+static TCGv cpu_rampX;
+static TCGv cpu_rampY;
+static TCGv cpu_rampZ;
+
+static TCGv cpu_r[NO_CPU_REGISTERS];
+static TCGv cpu_eind;
+static TCGv cpu_sp;
+
+static TCGv cpu_skip;
+
+static const char reg_names[NO_CPU_REGISTERS][8] = {
+    "r0",  "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
+    "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15",
+    "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
+    "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
+};
+#define REG(x) (cpu_r[x])
+
+enum {
+    DISAS_EXIT   = DISAS_TARGET_0,  /* We want return to the cpu main loop.  */
+    DISAS_LOOKUP = DISAS_TARGET_1,  /* We have a variable condition exit.  */
+    DISAS_CHAIN  = DISAS_TARGET_2,  /* We have a single condition exit.  */
+};
+
+typedef struct DisasContext DisasContext;
+
+/* This is the state at translation time. */
+struct DisasContext {
+    TranslationBlock *tb;
+
+    CPUAVRState *env;
+    CPUState *cs;
+
+    target_long npc;
+    uint32_t opcode;
+
+    /* Routine used to access memory */
+    int memidx;
+    int bstate;
+    int singlestep;
+
+    TCGv skip_var0;
+    TCGv skip_var1;
+    TCGCond skip_cond;
+    bool free_skip_var0;
+};
+
+static int to_A(DisasContext *ctx, int indx) { return 16 + (indx % 16); }
+static int to_B(DisasContext *ctx, int indx) { return 16 + (indx % 8); }
+static int to_C(DisasContext *ctx, int indx) { return 24 + (indx % 4) * 2; }
+static int to_D(DisasContext *ctx, int indx) { return (indx % 16) * 2; }
+
+static uint16_t next_word(DisasContext *ctx)
+{
+    return cpu_lduw_code(ctx->env, ctx->npc++ * 2);
+}
+
+static int append_16(DisasContext *ctx, int x)
+{
+    return x << 16 | next_word(ctx);
+}
+
+static bool decode_insn(DisasContext *ctx, uint16_t insn);
+#include "decode_insn.inc.c"
+
+static bool avr_have_feature(DisasContext *ctx, int feature)
+{
+    if (!avr_feature(ctx->env, feature)) {
+        gen_helper_unsupported(cpu_env);
+        ctx->bstate = DISAS_NORETURN;
+        return false;
+    }
+    return true;
+}
+
+static void gen_goto_tb(DisasContext *ctx, int n, target_ulong dest)
+{
+    TranslationBlock *tb = ctx->tb;
+
+    if (ctx->singlestep == 0) {
+        tcg_gen_goto_tb(n);
+        tcg_gen_movi_i32(cpu_pc, dest);
+        tcg_gen_exit_tb(tb, n);
+    } else {
+        tcg_gen_movi_i32(cpu_pc, dest);
+        gen_helper_debug(cpu_env);
+        tcg_gen_exit_tb(NULL, 0);
+    }
+    ctx->bstate = DISAS_NORETURN;
+}
+
+#include "exec/gen-icount.h"
+
+static void gen_add_CHf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+    TCGv t3 = tcg_temp_new_i32();
+
+    tcg_gen_and_tl(t1, Rd, Rr); /* t1 = Rd & Rr */
+    tcg_gen_andc_tl(t2, Rd, R); /* t2 = Rd & ~R */
+    tcg_gen_andc_tl(t3, Rr, R); /* t3 = Rr & ~R */
+    tcg_gen_or_tl(t1, t1, t2); /* t1 = t1 | t2 | t3 */
+    tcg_gen_or_tl(t1, t1, t3);
+
+    tcg_gen_shri_tl(cpu_Cf, t1, 7); /* Cf = t1(7) */
+    tcg_gen_shri_tl(cpu_Hf, t1, 3); /* Hf = t1(3) */
+    tcg_gen_andi_tl(cpu_Hf, cpu_Hf, 1);
+
+    tcg_temp_free_i32(t3);
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_add_Vf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+
+    /* t1 = Rd & Rr & ~R | ~Rd & ~Rr & R = (Rd ^ R) & ~(Rd ^ Rr) */
+    tcg_gen_xor_tl(t1, Rd, R);
+    tcg_gen_xor_tl(t2, Rd, Rr);
+    tcg_gen_andc_tl(t1, t1, t2);
+
+    tcg_gen_shri_tl(cpu_Vf, t1, 7); /* Vf = t1(7) */
+
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_sub_CHf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+    TCGv t3 = tcg_temp_new_i32();
+
+    /* Cf & Hf */
+    tcg_gen_not_tl(t1, Rd); /* t1 = ~Rd */
+    tcg_gen_and_tl(t2, t1, Rr); /* t2 = ~Rd & Rr */
+    tcg_gen_or_tl(t3, t1, Rr); /* t3 = (~Rd | Rr) & R */
+    tcg_gen_and_tl(t3, t3, R);
+    tcg_gen_or_tl(t2, t2, t3); /* t2 = ~Rd & Rr | ~Rd & R | R & Rr */
+    tcg_gen_shri_tl(cpu_Cf, t2, 7); /* Cf = t2(7) */
+    tcg_gen_shri_tl(cpu_Hf, t2, 3); /* Hf = t2(3) */
+    tcg_gen_andi_tl(cpu_Hf, cpu_Hf, 1);
+
+    tcg_temp_free_i32(t3);
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_sub_Vf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+
+    /* Vf */
+    /* t1 = Rd & ~Rr & ~R | ~Rd & Rr & R = (Rd ^ R) & (Rd ^ R) */
+    tcg_gen_xor_tl(t1, Rd, R);
+    tcg_gen_xor_tl(t2, Rd, Rr);
+    tcg_gen_and_tl(t1, t1, t2);
+    tcg_gen_shri_tl(cpu_Vf, t1, 7); /* Vf = t1(7) */
+
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_rshift_ZNVSf(TCGv R)
+{
+    tcg_gen_mov_tl(cpu_Zf, R); /* Zf = R */
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Vf, cpu_Nf, cpu_Cf);
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+static void gen_NSf(TCGv R)
+{
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+static void gen_ZNSf(TCGv R)
+{
+    tcg_gen_mov_tl(cpu_Zf, R); /* Zf = R */
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+static void gen_push_ret(DisasContext *ctx, int ret)
+{
+    if (avr_feature(ctx->env, AVR_FEATURE_1_BYTE_PC)) {
+
+        TCGv t0 = tcg_const_i32((ret & 0x0000ff));
+
+        tcg_gen_qemu_st_tl(t0, cpu_sp, MMU_DATA_IDX, MO_UB);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(t0);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_2_BYTE_PC)) {
+
+        TCGv t0 = tcg_const_i32((ret & 0x00ffff));
+
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_st_tl(t0, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(t0);
+
+    } else if (avr_feature(ctx->env, AVR_FEATURE_3_BYTE_PC)) {
+
+        TCGv lo = tcg_const_i32((ret & 0x0000ff));
+        TCGv hi = tcg_const_i32((ret & 0xffff00) >> 8);
+
+        tcg_gen_qemu_st_tl(lo, cpu_sp, MMU_DATA_IDX, MO_UB);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 2);
+        tcg_gen_qemu_st_tl(hi, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(lo);
+        tcg_temp_free_i32(hi);
+    }
+}
+
+static void gen_pop_ret(DisasContext *ctx, TCGv ret)
+{
+    if (avr_feature(ctx->env, AVR_FEATURE_1_BYTE_PC)) {
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(ret, cpu_sp, MMU_DATA_IDX, MO_UB);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_2_BYTE_PC)) {
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(ret, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_3_BYTE_PC)) {
+        TCGv lo = tcg_temp_new_i32();
+        TCGv hi = tcg_temp_new_i32();
+
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(hi, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 2);
+        tcg_gen_qemu_ld_tl(lo, cpu_sp, MMU_DATA_IDX, MO_UB);
+
+        tcg_gen_deposit_tl(ret, lo, hi, 8, 16);
+
+        tcg_temp_free_i32(lo);
+        tcg_temp_free_i32(hi);
+    }
+}
+
+static void gen_jmp_ez(DisasContext *ctx)
+{
+    tcg_gen_deposit_tl(cpu_pc, cpu_r[30], cpu_r[31], 8, 8);
+    tcg_gen_or_tl(cpu_pc, cpu_pc, cpu_eind);
+    ctx->bstate = DISAS_LOOKUP;
+}
+
+static void gen_jmp_z(DisasContext *ctx)
+{
+    tcg_gen_deposit_tl(cpu_pc, cpu_r[30], cpu_r[31], 8, 8);
+    ctx->bstate = DISAS_LOOKUP;
+}
+
+/*
+ *  in the gen_set_addr & gen_get_addr functions
+ *  H assumed to be in 0x00ff0000 format
+ *  M assumed to be in 0x000000ff format
+ *  L assumed to be in 0x000000ff format
+ */
+static void gen_set_addr(TCGv addr, TCGv H, TCGv M, TCGv L)
+{
+
+    tcg_gen_andi_tl(L, addr, 0x000000ff);
+
+    tcg_gen_andi_tl(M, addr, 0x0000ff00);
+    tcg_gen_shri_tl(M, M, 8);
+
+    tcg_gen_andi_tl(H, addr, 0x00ff0000);
+}
+
+static void gen_set_xaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampX, cpu_r[27], cpu_r[26]);
+}
+
+static void gen_set_yaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampY, cpu_r[29], cpu_r[28]);
+}
+
+static void gen_set_zaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampZ, cpu_r[31], cpu_r[30]);
+}
+
+static TCGv gen_get_addr(TCGv H, TCGv M, TCGv L)
+{
+    TCGv addr = tcg_temp_new_i32();
+
+    tcg_gen_deposit_tl(addr, M, H, 8, 8);
+    tcg_gen_deposit_tl(addr, L, addr, 8, 16);
+
+    return addr;
+}
+
+static TCGv gen_get_xaddr(void)
+{
+    return gen_get_addr(cpu_rampX, cpu_r[27], cpu_r[26]);
+}
+
+static TCGv gen_get_yaddr(void)
+{
+    return gen_get_addr(cpu_rampY, cpu_r[29], cpu_r[28]);
+}
+
+static TCGv gen_get_zaddr(void)
+{
+    return gen_get_addr(cpu_rampZ, cpu_r[31], cpu_r[30]);
+}
+
+/*
+ *  Adds two registers and the contents of the C Flag and places the result in
+ *  the destination register Rd.
+ */
+static bool trans_ADC(DisasContext *ctx, arg_ADC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_add_tl(R, Rd, Rr); /* R = Rd + Rr + Cf */
+    tcg_gen_add_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_add_CHf(R, Rd, Rr);
+    gen_add_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Adds two registers without the C Flag and places the result in the
+ *  destination register Rd.
+ */
+static bool trans_ADD(DisasContext *ctx, arg_ADD *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_add_tl(R, Rd, Rr); /* Rd = Rd + Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_add_CHf(R, Rd, Rr);
+    gen_add_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Adds an immediate value (0 - 63) to a register pair and places the result
+ *  in the register pair. This instruction operates on the upper four register
+ *  pairs, and is well suited for operations on the pointer registers.  This
+ *  instruction is not available in all devices. Refer to the device specific
+ *  instruction set summary.
+ */
+static bool trans_ADIW(DisasContext *ctx, arg_ADIW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ADIW_SBIW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    int Imm = (a->imm);
+    TCGv R = tcg_temp_new_i32();
+    TCGv Rd = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_deposit_tl(Rd, RdL, RdH, 8, 8); /* Rd = RdH:RdL */
+    tcg_gen_addi_tl(R, Rd, Imm); /* R = Rd + Imm */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* Cf */
+    tcg_gen_andc_tl(cpu_Cf, Rd, R); /* Cf = Rd & ~R */
+    tcg_gen_shri_tl(cpu_Cf, cpu_Cf, 15);
+
+    /* Vf */
+    tcg_gen_andc_tl(cpu_Vf, R, Rd); /* Vf = R & ~Rd */
+    tcg_gen_shri_tl(cpu_Vf, cpu_Vf, 15);
+
+    /* Zf */
+    tcg_gen_mov_tl(cpu_Zf, R); /* Zf = R */
+
+    /* Nf */
+    tcg_gen_shri_tl(cpu_Nf, R, 15); /* Nf = R(15) */
+
+    /* Sf */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf);/* Sf = Nf ^ Vf */
+
+    /* R */
+    tcg_gen_andi_tl(RdL, R, 0xff);
+    tcg_gen_shri_tl(RdH, R, 8);
+
+    tcg_temp_free_i32(Rd);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical AND between the contents of register Rd and register
+ *  Rr and places the result in the destination register Rd.
+ */
+static bool trans_AND(DisasContext *ctx, arg_AND *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_and_tl(R, Rd, Rr); /* Rd = Rd and Rr */
+
+    /* Vf */
+    tcg_gen_movi_tl(cpu_Vf, 0x00); /* Vf = 0 */
+
+    /* Zf */
+    tcg_gen_mov_tl(cpu_Zf, R); /* Zf = R */
+
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical AND between the contents of register Rd and a constant
+ *  and places the result in the destination register Rd.
+ */
+static bool trans_ANDI(DisasContext *ctx, arg_ANDI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = (a->imm);
+
+    /* op */
+    tcg_gen_andi_tl(Rd, Rd, Imm); /* Rd = Rd & Imm */
+
+    tcg_gen_movi_tl(cpu_Vf, 0x00); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. Bit 7 is held constant. Bit 0
+ *  is loaded into the C Flag of the SREG. This operation effectively divides a
+ *  signed value by two without changing its sign. The Carry Flag can be used to
+ *  round the result.
+ */
+static bool trans_ASR(DisasContext *ctx, arg_ASR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+
+    /* Cf */
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1); /* Cf = Rd(0) */
+
+    /* op */
+    tcg_gen_andi_tl(t0, Rd, 0x80); /* Rd = (Rd & 0x80) | (Rd >> 1) */
+    tcg_gen_shri_tl(Rd, Rd, 1);
+    tcg_gen_or_tl(Rd, Rd, t0);
+
+    gen_rshift_ZNVSf(Rd);
+
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  Clears a single Flag in SREG.
+ */
+static bool trans_BCLR(DisasContext *ctx, arg_BCLR *a)
+{
+    switch (a->bit) {
+    case 0x00:
+        tcg_gen_movi_tl(cpu_Cf, 0x00);
+        break;
+    case 0x01:
+        tcg_gen_movi_tl(cpu_Zf, 0x01);
+        break;
+    case 0x02:
+        tcg_gen_movi_tl(cpu_Nf, 0x00);
+        break;
+    case 0x03:
+        tcg_gen_movi_tl(cpu_Vf, 0x00);
+        break;
+    case 0x04:
+        tcg_gen_movi_tl(cpu_Sf, 0x00);
+        break;
+    case 0x05:
+        tcg_gen_movi_tl(cpu_Hf, 0x00);
+        break;
+    case 0x06:
+        tcg_gen_movi_tl(cpu_Tf, 0x00);
+        break;
+    case 0x07:
+        tcg_gen_movi_tl(cpu_If, 0x00);
+        break;
+    }
+
+    return true;
+}
+
+/*
+ *  Copies the T Flag in the SREG (Status Register) to bit b in register Rd.
+ */
+static bool trans_BLD(DisasContext *ctx, arg_BLD *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_andi_tl(Rd, Rd, ~(1u << a->bit)); /* clear bit */
+    tcg_gen_shli_tl(t1, cpu_Tf, a->bit); /* create mask */
+    tcg_gen_or_tl(Rd, Rd, t1);
+
+    tcg_temp_free_i32(t1);
+
+    return true;
+}
+
+/*
+ *  Conditional relative branch. Tests a single bit in SREG and branches
+ *  relatively to PC if the bit is cleared. This instruction branches relatively
+ *  to PC in either direction (PC - 63 < = destination <= PC + 64). The
+ *  parameter k is the offset from PC and is represented in two's complement
+ *  form.
+ */
+static bool trans_BRBC(DisasContext *ctx, arg_BRBC *a)
+{
+    TCGLabel *not_taken = gen_new_label();
+    TCGCond cond = TCG_COND_EQ;
+    TCGv var;
+
+    switch (a->bit) {
+    case 0x00:
+        var = cpu_Cf;
+        break;
+    case 0x01:
+        cond = TCG_COND_NE;
+        var = cpu_Zf;
+        break;
+    case 0x02:
+        var = cpu_Nf;
+        break;
+    case 0x03:
+        var = cpu_Vf;
+        break;
+    case 0x04:
+        var = cpu_Sf;
+        break;
+    case 0x05:
+        var = cpu_Hf;
+        break;
+    case 0x06:
+        var = cpu_Tf;
+        break;
+    case 0x07:
+        var = cpu_If;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    tcg_gen_brcondi_i32(tcg_invert_cond(cond), var, 0, not_taken);
+    gen_goto_tb(ctx, 0, ctx->npc + a->imm);
+    gen_set_label(not_taken);
+
+    ctx->bstate = DISAS_CHAIN;
+    return true;
+}
+
+/*
+ *  Conditional relative branch. Tests a single bit in SREG and branches
+ *  relatively to PC if the bit is set. This instruction branches relatively to
+ *  PC in either direction (PC - 63 < = destination <= PC + 64). The parameter k
+ *  is the offset from PC and is represented in two's complement form.
+ */
+static bool trans_BRBS(DisasContext *ctx, arg_BRBS *a)
+{
+    TCGLabel *not_taken = gen_new_label();
+    TCGCond cond = TCG_COND_NE;
+    TCGv var;
+
+    switch (a->bit) {
+    case 0x00:
+        var = cpu_Cf;
+        break;
+    case 0x01:
+        cond = TCG_COND_EQ;
+        var = cpu_Zf;
+        break;
+    case 0x02:
+        var = cpu_Nf;
+        break;
+    case 0x03:
+        var = cpu_Vf;
+        break;
+    case 0x04:
+        var = cpu_Sf;
+        break;
+    case 0x05:
+        var = cpu_Hf;
+        break;
+    case 0x06:
+        var = cpu_Tf;
+        break;
+    case 0x07:
+        var = cpu_If;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    tcg_gen_brcondi_i32(tcg_invert_cond(cond), var, 0, not_taken);
+    gen_goto_tb(ctx, 0, ctx->npc + a->imm);
+    gen_set_label(not_taken);
+
+    ctx->bstate = DISAS_CHAIN;
+    return true;
+}
+
+/*
+ *  Sets a single Flag or bit in SREG.
+ */
+static bool trans_BSET(DisasContext *ctx, arg_BSET *a)
+{
+    switch (a->bit) {
+    case 0x00:
+        tcg_gen_movi_tl(cpu_Cf, 0x01);
+        break;
+    case 0x01:
+        tcg_gen_movi_tl(cpu_Zf, 0x00);
+        break;
+    case 0x02:
+        tcg_gen_movi_tl(cpu_Nf, 0x01);
+        break;
+    case 0x03:
+        tcg_gen_movi_tl(cpu_Vf, 0x01);
+        break;
+    case 0x04:
+        tcg_gen_movi_tl(cpu_Sf, 0x01);
+        break;
+    case 0x05:
+        tcg_gen_movi_tl(cpu_Hf, 0x01);
+        break;
+    case 0x06:
+        tcg_gen_movi_tl(cpu_Tf, 0x01);
+        break;
+    case 0x07:
+        tcg_gen_movi_tl(cpu_If, 0x01);
+        break;
+    }
+
+    return true;
+}
+
+/*
+ *  The BREAK instruction is used by the On-chip Debug system, and is
+ *  normally not used in the application software. When the BREAK instruction is
+ *  executed, the AVR CPU is set in the Stopped Mode. This gives the On-chip
+ *  Debugger access to internal resources.  If any Lock bits are set, or either
+ *  the JTAGEN or OCDEN Fuses are unprogrammed, the CPU will treat the BREAK
+ *  instruction as a NOP and will not enter the Stopped mode.  This instruction
+ *  is not available in all devices. Refer to the device specific instruction
+ *  set summary.
+ */
+static bool trans_BREAK(DisasContext *ctx, arg_BREAK *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_BREAK)) {
+        return true;
+    }
+
+#ifdef BREAKPOINT_ON_BREAK
+    tcg_gen_movi_tl(cpu_pc, ctx->npc - 1);
+    gen_helper_debug(cpu_env);
+    ctx->bstate = DISAS_EXIT;
+#else
+    /* NOP */
+#endif
+
+    return true;
+}
+
+/*
+ *  Stores bit b from Rd to the T Flag in SREG (Status Register).
+ */
+static bool trans_BST(DisasContext *ctx, arg_BST *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_andi_tl(cpu_Tf, Rd, 1 << a->bit);
+    tcg_gen_shri_tl(cpu_Tf, cpu_Tf, a->bit);
+
+    return true;
+}
+
+/*
+ *  Calls to a subroutine within the entire Program memory. The return
+ *  address (to the instruction after the CALL) will be stored onto the Stack.
+ *  (See also RCALL). The Stack Pointer uses a post-decrement scheme during
+ *  CALL.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_CALL(DisasContext *ctx, arg_CALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_JMP_CALL)) {
+        return true;
+    }
+
+    int Imm = a->imm;
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_goto_tb(ctx, 0, Imm);
+
+    return true;
+}
+
+/*
+ *  Clears a specified bit in an I/O Register. This instruction operates on
+ *  the lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_CBI(DisasContext *ctx, arg_CBI *a)
+{
+    TCGv data = tcg_temp_new_i32();
+    TCGv port = tcg_const_i32(a->reg);
+
+    gen_helper_inb(data, cpu_env, port);
+    tcg_gen_andi_tl(data, data, ~(1 << a->bit));
+    gen_helper_outb(cpu_env, port, data);
+
+    tcg_temp_free_i32(data);
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  Clears the specified bits in register Rd. Performs the logical AND
+ *  between the contents of register Rd and the complement of the constant mask
+ *  K. The result will be placed in register Rd.
+ */
+static bool trans_COM(DisasContext *ctx, arg_COM *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_xori_tl(Rd, Rd, 0xff);
+
+    tcg_gen_movi_tl(cpu_Cf, 1); /* Cf = 1 */
+    tcg_gen_movi_tl(cpu_Vf, 0); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr.
+ *  None of the registers are changed. All conditional branches can be used
+ *  after this instruction.
+ */
+static bool trans_CP(DisasContext *ctx, arg_CP *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr and
+ *  also takes into account the previous carry. None of the registers are
+ *  changed. All conditional branches can be used after this instruction.
+ */
+static bool trans_CPC(DisasContext *ctx, arg_CPC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_or_tl(cpu_Zf, cpu_Zf, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between register Rd and a constant.
+ *  The register is not changed. All conditional branches can be used after this
+ *  instruction.
+ */
+static bool trans_CPI(DisasContext *ctx, arg_CPI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = a->imm;
+    TCGv Rr = tcg_const_i32(Imm);
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr, and
+ *  skips the next instruction if Rd = Rr.
+ */
+static bool trans_CPSE(DisasContext *ctx, arg_CPSE *a)
+{
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = cpu_r[a->rd];
+    ctx->skip_var1 = cpu_r[a->rr];
+    return true;
+}
+
+/*
+ *  Subtracts one -1- from the contents of register Rd and places the result
+ *  in the destination register Rd.  The C Flag in SREG is not affected by the
+ *  operation, thus allowing the DEC instruction to be used on a loop counter in
+ *  multiple-precision computations.  When operating on unsigned values, only
+ *  BREQ and BRNE branches can be expected to perform consistently.  When
+ *  operating on two's complement values, all signed branches are available.
+ */
+static bool trans_DEC(DisasContext *ctx, arg_DEC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_subi_tl(Rd, Rd, 1); /* Rd = Rd - 1 */
+    tcg_gen_andi_tl(Rd, Rd, 0xff); /* make it 8 bits */
+
+    /* cpu_Vf = Rd == 0x7f */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Vf, Rd, 0x7f);
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  The module is an instruction set extension to the AVR CPU, performing
+ *  DES iterations. The 64-bit data block (plaintext or ciphertext) is placed in
+ *  the CPU register file, registers R0-R7, where LSB of data is placed in LSB
+ *  of R0 and MSB of data is placed in MSB of R7. The full 64-bit key (including
+ *  parity bits) is placed in registers R8- R15, organized in the register file
+ *  with LSB of key in LSB of R8 and MSB of key in MSB of R15. Executing one DES
+ *  instruction performs one round in the DES algorithm. Sixteen rounds must be
+ *  executed in increasing order to form the correct DES ciphertext or
+ *  plaintext. Intermediate results are stored in the register file (R0-R15)
+ *  after each DES instruction. The instruction's operand (K) determines which
+ *  round is executed, and the half carry flag (H) determines whether encryption
+ *  or decryption is performed.  The DES algorithm is described in
+ *  "Specifications for the Data Encryption Standard" (Federal Information
+ *  Processing Standards Publication 46). Intermediate results in this
+ *  implementation differ from the standard because the initial permutation and
+ *  the inverse initial permutation are performed each iteration. This does not
+ *  affect the result in the final ciphertext or plaintext, but reduces
+ *  execution time.
+ */
+static bool trans_DES(DisasContext *ctx, arg_DES *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_DES)) {
+        return true;
+    }
+
+    return true;
+}
+
+/*
+ *  Indirect call of a subroutine pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File and the EIND Register in the I/O space. This
+ *  instruction allows for indirect calls to the entire 4M (words) Program
+ *  memory space. See also ICALL. The Stack Pointer uses a post-decrement scheme
+ *  during EICALL.  This instruction is not available in all devices. Refer to
+ *  the device specific instruction set summary.
+ */
+static bool trans_EICALL(DisasContext *ctx, arg_EICALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_EIJMP_EICALL)) {
+        return true;
+    }
+
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_jmp_ez(ctx);
+    return true;
+}
+
+/*
+ *  Indirect jump to the address pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File and the EIND Register in the I/O space. This
+ *  instruction allows for indirect jumps to the entire 4M (words) Program
+ *  memory space. See also IJMP.  This instruction is not available in all
+ *  devices. Refer to the device specific instruction set summary.
+ */
+static bool trans_EIJMP(DisasContext *ctx, arg_EIJMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_EIJMP_EICALL)) {
+        return true;
+    }
+
+    gen_jmp_ez(ctx);
+    return true;
+}
+
+/*
+ *  Loads one byte pointed to by the Z-register and the RAMPZ Register in
+ *  the I/O space, and places this byte in the destination register Rd. This
+ *  instruction features a 100% space effective constant initialization or
+ *  constant data fetch. The Program memory is organized in 16-bit words while
+ *  the Z-pointer is a byte address. Thus, the least significant bit of the
+ *  Z-pointer selects either low byte (ZLSB = 0) or high byte (ZLSB = 1). This
+ *  instruction can address the entire Program memory space. The Z-pointer
+ *  Register can either be left unchanged by the operation, or it can be
+ *  incremented. The incrementation applies to the entire 24-bit concatenation
+ *  of the RAMPZ and Z-pointer Registers.  Devices with Self-Programming
+ *  capability can use the ELPM instruction to read the Fuse and Lock bit value.
+ *  Refer to the device documentation for a detailed description.  This
+ *  instruction is not available in all devices. Refer to the device specific
+ *  instruction set summary.
+ */
+static bool trans_ELPM1(DisasContext *ctx, arg_ELPM1 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[0];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_ELPM2(DisasContext *ctx, arg_ELPM2 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_ELPMX(DisasContext *ctx, arg_ELPMX *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPMX)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Performs the logical EOR between the contents of register Rd and
+ *  register Rr and places the result in the destination register Rd.
+ */
+static bool trans_EOR(DisasContext *ctx, arg_EOR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+
+    tcg_gen_xor_tl(Rd, Rd, Rr);
+
+    tcg_gen_movi_tl(cpu_Vf, 0);
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit unsigned
+ *  multiplication and shifts the result one bit left.
+ */
+static bool trans_FMUL(DisasContext *ctx, arg_FMUL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_mul_tl(R, Rd, Rr); /* R = Rd *Rr */
+    tcg_gen_shli_tl(R, R, 1);
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 16); /* Cf = R(16) */
+    tcg_gen_andi_tl(cpu_Zf, R, 0x0000ffff);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication
+ *  and shifts the result one bit left.
+ */
+static bool trans_FMULS(DisasContext *ctx, arg_FMULS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_ext8s_tl(t1, Rr); /* make Rr full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, t1); /* R = Rd *Rr */
+    tcg_gen_shli_tl(R, R, 1);
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 16); /* Cf = R(16) */
+    tcg_gen_andi_tl(cpu_Zf, R, 0x0000ffff);
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication
+ *  and shifts the result one bit left.
+ */
+static bool trans_FMULSU(DisasContext *ctx, arg_FMULSU *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, Rr); /* R = Rd *Rr */
+    tcg_gen_shli_tl(R, R, 1);
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 16); /* Cf = R(16) */
+    tcg_gen_andi_tl(cpu_Zf, R, 0x0000ffff);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Calls to a subroutine within the entire 4M (words) Program memory. The
+ *  return address (to the instruction after the CALL) will be stored onto the
+ *  Stack. See also RCALL. The Stack Pointer uses a post-decrement scheme during
+ *  CALL.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_ICALL(DisasContext *ctx, arg_ICALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_IJMP_ICALL)) {
+        return true;
+    }
+
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_jmp_z(ctx);
+
+    return true;
+}
+
+/*
+ *  Indirect jump to the address pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. The Z-pointer Register is 16 bits wide and
+ *  allows jump within the lowest 64K words (128KB) section of Program memory.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_IJMP(DisasContext *ctx, arg_IJMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_IJMP_ICALL)) {
+        return true;
+    }
+
+    gen_jmp_z(ctx);
+
+    return true;
+}
+
+/*
+ *  Loads data from the I/O Space (Ports, Timers, Configuration Registers,
+ *  etc.) into register Rd in the Register File.
+ */
+static bool trans_IN(DisasContext *ctx, arg_IN *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv port = tcg_const_i32(a->imm);
+
+    gen_helper_inb(Rd, cpu_env, port);
+
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  Adds one -1- to the contents of register Rd and places the result in the
+ *  destination register Rd.  The C Flag in SREG is not affected by the
+ *  operation, thus allowing the INC instruction to be used on a loop counter in
+ *  multiple-precision computations.  When operating on unsigned numbers, only
+ *  BREQ and BRNE branches can be expected to perform consistently. When
+ *  operating on two's complement values, all signed branches are available.
+ */
+static bool trans_INC(DisasContext *ctx, arg_INC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_addi_tl(Rd, Rd, 1);
+    tcg_gen_andi_tl(Rd, Rd, 0xff);
+
+    /* cpu_Vf = Rd == 0x80 */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Vf, Rd, 0x80);
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Jump to an address within the entire 4M (words) Program memory. See also
+ *  RJMP.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.0
+ */
+static bool trans_JMP(DisasContext *ctx, arg_JMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_JMP_CALL)) {
+        return true;
+    }
+
+    gen_goto_tb(ctx, 0, a->imm);
+
+    return true;
+}
+
+/*
+ *  Load one byte indirect from data space to register and stores an clear
+ *  the bits in data space specified by the register. The instruction can only
+ *  be used towards internal SRAM.  The data location is pointed to by the Z (16
+ *  bits) Pointer Register in the Register File. Memory access is limited to the
+ *  current data segment of 64KB. To access another data segment in devices with
+ *  more than 64KB data space, the RAMPZ in register in the I/O area has to be
+ *  changed.  The Z-pointer Register is left unchanged by the operation. This
+ *  instruction is especially suited for clearing status bits stored in SRAM.
+ */
+static void gen_data_store(DisasContext *ctx, TCGv data, TCGv addr)
+{
+    if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        gen_helper_fullwr(cpu_env, data, addr);
+    } else {
+        tcg_gen_qemu_st8(data, addr, MMU_DATA_IDX); /* mem[addr] = data */
+    }
+}
+
+static void gen_data_load(DisasContext *ctx, TCGv data, TCGv addr)
+{
+    if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        gen_helper_fullrd(data, cpu_env, addr);
+    } else {
+        tcg_gen_qemu_ld8u(data, addr, MMU_DATA_IDX); /* data = mem[addr] */
+    }
+}
+
+static bool trans_LAC(DisasContext *ctx, arg_LAC *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rr = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+        /* t1 = t0 & (0xff - Rr) = t0 and ~Rr */
+    tcg_gen_andc_tl(t1, t0, Rr);
+
+    tcg_gen_mov_tl(Rr, t0); /* Rr = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Load one byte indirect from data space to register and set bits in data
+ *  space specified by the register. The instruction can only be used towards
+ *  internal SRAM.  The data location is pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. Memory access is limited to the current data
+ *  segment of 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPZ in register in the I/O area has to be changed.
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for setting status bits stored in SRAM.
+ */
+static bool trans_LAS(DisasContext *ctx, arg_LAS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rr = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+    tcg_gen_or_tl(t1, t0, Rr);
+
+    tcg_gen_mov_tl(Rr, t0); /* Rr = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Load one byte indirect from data space to register and toggles bits in
+ *  the data space specified by the register.  The instruction can only be used
+ *  towards SRAM.  The data location is pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. Memory access is limited to the current data
+ *  segment of 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPZ in register in the I/O area has to be changed.
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for changing status bits stored in SRAM.
+ */
+static bool trans_LAT(DisasContext *ctx, arg_LAT *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+    tcg_gen_xor_tl(t1, t0, Rd);
+
+    tcg_gen_mov_tl(Rd, t0); /* Rd = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect from the data space to a register. For parts
+ *  with SRAM, the data space consists of the Register File, I/O memory and
+ *  internal SRAM (and external SRAM if applicable). For parts without SRAM, the
+ *  data space consists of the Register File only. In some parts the Flash
+ *  Memory has been mapped to the data space and can be read using this command.
+ *  The EEPROM has a separate address space.  The data location is pointed to by
+ *  the X (16 bits) Pointer Register in the Register File. Memory access is
+ *  limited to the current data segment of 64KB. To access another data segment
+ *  in devices with more than 64KB data space, the RAMPX in register in the I/O
+ *  area has to be changed.  The X-pointer Register can either be left unchanged
+ *  by the operation, or it can be post-incremented or predecremented.  These
+ *  features are especially suited for accessing arrays, tables, and Stack
+ *  Pointer usage of the X-pointer Register. Note that only the low byte of the
+ *  X-pointer is updated in devices with no more than 256 bytes data space. For
+ *  such devices, the high byte of the pointer is not used by this instruction
+ *  and can be used for other purposes. The RAMPX Register in the I/O area is
+ *  updated in parts with more than 64KB data space or more than 64KB Program
+ *  memory, and the increment/decrement is added to the entire 24-bit address on
+ *  such devices.  Not all variants of this instruction is available in all
+ *  devices. Refer to the device specific instruction set summary.  In the
+ *  Reduced Core tinyAVR the LD instruction can be used to achieve the same
+ *  operation as LPM since the program memory is mapped to the data memory
+ *  space.
+ */
+static bool trans_LDX1(DisasContext *ctx, arg_LDX1 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDX2(DisasContext *ctx, arg_LDX2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDX3(DisasContext *ctx, arg_LDX3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect with or without displacement from the data space
+ *  to a register. For parts with SRAM, the data space consists of the Register
+ *  File, I/O memory and internal SRAM (and external SRAM if applicable). For
+ *  parts without SRAM, the data space consists of the Register File only. In
+ *  some parts the Flash Memory has been mapped to the data space and can be
+ *  read using this command. The EEPROM has a separate address space.  The data
+ *  location is pointed to by the Y (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPY in register in the I/O area has to be changed.  The Y-pointer Register
+ *  can either be left unchanged by the operation, or it can be post-incremented
+ *  or predecremented.  These features are especially suited for accessing
+ *  arrays, tables, and Stack Pointer usage of the Y-pointer Register. Note that
+ *  only the low byte of the Y-pointer is updated in devices with no more than
+ *  256 bytes data space. For such devices, the high byte of the pointer is not
+ *  used by this instruction and can be used for other purposes. The RAMPY
+ *  Register in the I/O area is updated in parts with more than 64KB data space
+ *  or more than 64KB Program memory, and the increment/decrement/displacement
+ *  is added to the entire 24-bit address on such devices.  Not all variants of
+ *  this instruction is available in all devices. Refer to the device specific
+ *  instruction set summary.  In the Reduced Core tinyAVR the LD instruction can
+ *  be used to achieve the same operation as LPM since the program memory is
+ *  mapped to the data memory space.
+ */
+static bool trans_LDY2(DisasContext *ctx, arg_LDY2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDY3(DisasContext *ctx, arg_LDY3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDDY(DisasContext *ctx, arg_LDDY *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect with or without displacement from the data space
+ *  to a register. For parts with SRAM, the data space consists of the Register
+ *  File, I/O memory and internal SRAM (and external SRAM if applicable). For
+ *  parts without SRAM, the data space consists of the Register File only. In
+ *  some parts the Flash Memory has been mapped to the data space and can be
+ *  read using this command. The EEPROM has a separate address space.  The data
+ *  location is pointed to by the Z (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPZ in register in the I/O area has to be changed.  The Z-pointer Register
+ *  can either be left unchanged by the operation, or it can be post-incremented
+ *  or predecremented.  These features are especially suited for Stack Pointer
+ *  usage of the Z-pointer Register, however because the Z-pointer Register can
+ *  be used for indirect subroutine calls, indirect jumps and table lookup, it
+ *  is often more convenient to use the X or Y-pointer as a dedicated Stack
+ *  Pointer. Note that only the low byte of the Z-pointer is updated in devices
+ *  with no more than 256 bytes data space. For such devices, the high byte of
+ *  the pointer is not used by this instruction and can be used for other
+ *  purposes. The RAMPZ Register in the I/O area is updated in parts with more
+ *  than 64KB data space or more than 64KB Program memory, and the
+ *  increment/decrement/displacement is added to the entire 24-bit address on
+ *  such devices.  Not all variants of this instruction is available in all
+ *  devices. Refer to the device specific instruction set summary.  In the
+ *  Reduced Core tinyAVR the LD instruction can be used to achieve the same
+ *  operation as LPM since the program memory is mapped to the data memory
+ *  space.  For using the Z-pointer for table lookup in Program memory see the
+ *  LPM and ELPM instructions.
+ */
+static bool trans_LDZ2(DisasContext *ctx, arg_LDZ2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDZ3(DisasContext *ctx, arg_LDZ3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDDZ(DisasContext *ctx, arg_LDDZ *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ * Loads an 8 bit constant directly to register 16 to 31.
+ */
+static bool trans_LDI(DisasContext *ctx, arg_LDI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int imm = a->imm;
+
+    tcg_gen_movi_tl(Rd, imm);
+
+    return true;
+}
+
+/*
+ *  Loads one byte from the data space to a register. For parts with SRAM,
+ *  the data space consists of the Register File, I/O memory and internal SRAM
+ *  (and external SRAM if applicable). For parts without SRAM, the data space
+ *  consists of the register file only. The EEPROM has a separate address space.
+ *  A 16-bit address must be supplied. Memory access is limited to the current
+ *  data segment of 64KB. The LDS instruction uses the RAMPD Register to access
+ *  memory above 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPD in register in the I/O area has to be changed.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_LDS(DisasContext *ctx, arg_LDS *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_rampD;
+    a->imm = next_word(ctx);
+
+    tcg_gen_mov_tl(addr, H); /* addr = H:M:L */
+    tcg_gen_shli_tl(addr, addr, 16);
+    tcg_gen_ori_tl(addr, addr, a->imm);
+
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte pointed to by the Z-register into the destination
+ *  register Rd. This instruction features a 100% space effective constant
+ *  initialization or constant data fetch. The Program memory is organized in
+ *  16-bit words while the Z-pointer is a byte address. Thus, the least
+ *  significant bit of the Z-pointer selects either low byte (ZLSB = 0) or high
+ *  byte (ZLSB = 1). This instruction can address the first 64KB (32K words) of
+ *  Program memory. The Zpointer Register can either be left unchanged by the
+ *  operation, or it can be incremented. The incrementation does not apply to
+ *  the RAMPZ Register.  Devices with Self-Programming capability can use the
+ *  LPM instruction to read the Fuse and Lock bit values.  Refer to the device
+ *  documentation for a detailed description.  The LPM instruction is not
+ *  available in all devices. Refer to the device specific instruction set
+ *  summary
+ */
+static bool trans_LPM1(DisasContext *ctx, arg_LPM1 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[0];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LPM2(DisasContext *ctx, arg_LPM2 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LPMX(DisasContext *ctx, arg_LPMX *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPMX)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    tcg_gen_andi_tl(L, addr, 0xff);
+
+    tcg_gen_shri_tl(addr, addr, 8);
+    tcg_gen_andi_tl(H, addr, 0xff);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. Bit 7 is cleared. Bit 0 is
+ *  loaded into the C Flag of the SREG. This operation effectively divides an
+ *  unsigned value by two. The C Flag can be used to round the result.
+ */
+static bool trans_LSR(DisasContext *ctx, arg_LSR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1);
+
+    tcg_gen_shri_tl(Rd, Rd, 1);
+
+    tcg_gen_mov_tl(cpu_Zf, Rd);
+    tcg_gen_movi_tl(cpu_Nf, 0);
+    tcg_gen_mov_tl(cpu_Vf, cpu_Cf);
+    tcg_gen_mov_tl(cpu_Sf, cpu_Vf);
+
+    return true;
+}
+
+/*
+ *  This instruction makes a copy of one register into another. The source
+ *  register Rr is left unchanged, while the destination register Rd is loaded
+ *  with a copy of Rr.
+ */
+static bool trans_MOV(DisasContext *ctx, arg_MOV *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+
+    tcg_gen_mov_tl(Rd, Rr);
+
+    return true;
+}
+
+/*
+ *  This instruction makes a copy of one register pair into another register
+ *  pair. The source register pair Rr+1:Rr is left unchanged, while the
+ *  destination register pair Rd+1:Rd is loaded with a copy of Rr + 1:Rr.  This
+ *  instruction is not available in all devices. Refer to the device specific
+ *  instruction set summary.
+ */
+static bool trans_MOVW(DisasContext *ctx, arg_MOVW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MOVW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    TCGv RrL = cpu_r[a->rr];
+    TCGv RrH = cpu_r[a->rr + 1];
+
+    tcg_gen_mov_tl(RdH, RrH);
+    tcg_gen_mov_tl(RdL, RrL);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit unsigned multiplication.
+ */
+static bool trans_MUL(DisasContext *ctx, arg_MUL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_mul_tl(R, Rd, Rr); /* R = Rd *Rr */
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(16) */
+    tcg_gen_mov_tl(cpu_Zf, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication.
+ */
+static bool trans_MULS(DisasContext *ctx, arg_MULS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_ext8s_tl(t1, Rr); /* make Rr full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, t1); /* R = Rd * Rr */
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(16) */
+    tcg_gen_mov_tl(cpu_Zf, R);
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit multiplication of a
+ *  signed and an unsigned number.
+ */
+static bool trans_MULSU(DisasContext *ctx, arg_MULSU *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, Rr); /* R = Rd *Rr */
+
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    tcg_gen_shri_tl(cpu_Cf, R, 16); /* Cf = R(16) */
+    tcg_gen_mov_tl(cpu_Zf, R);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Replaces the contents of register Rd with its two's complement; the
+ *  value $80 is left unchanged.
+ */
+static bool trans_NEG(DisasContext *ctx, arg_NEG *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_const_i32(0);
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, t0, Rd); /* R = 0 - Rd */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, t0, Rd);
+    gen_sub_Vf(R, t0, Rd);
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a single cycle No Operation.
+ */
+static bool trans_NOP(DisasContext *ctx, arg_NOP *a)
+{
+
+    /* NOP */
+
+    return true;
+}
+
+/*
+ *  Performs the logical OR between the contents of register Rd and register
+ *  Rr and places the result in the destination register Rd.
+ */
+static bool trans_OR(DisasContext *ctx, arg_OR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_or_tl(R, Rd, Rr);
+
+    tcg_gen_movi_tl(cpu_Vf, 0);
+    gen_ZNSf(R);
+
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical OR between the contents of register Rd and a
+ *  constant and places the result in the destination register Rd.
+ */
+static bool trans_ORI(DisasContext *ctx, arg_ORI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = (a->imm);
+
+    tcg_gen_ori_tl(Rd, Rd, Imm); /* Rd = Rd | Imm */
+
+    tcg_gen_movi_tl(cpu_Vf, 0x00); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Stores data from register Rr in the Register File to I/O Space (Ports,
+ *  Timers, Configuration Registers, etc.).
+ */
+static bool trans_OUT(DisasContext *ctx, arg_OUT *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv port = tcg_const_i32(a->imm);
+
+    gen_helper_outb(cpu_env, port, Rd);
+
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  This instruction loads register Rd with a byte from the STACK. The Stack
+ *  Pointer is pre-incremented by 1 before the POP.  This instruction is not
+ *  available in all devices. Refer to the device specific instruction set
+ *  summary.
+ */
+static bool trans_POP(DisasContext *ctx, arg_POP *a)
+{
+    /*
+     * Using a temp to work around some strange behaviour:
+     * tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+     * gen_data_load(ctx, Rd, cpu_sp);
+     * seems to cause the add to happen twice.
+     * This doesn't happen if either the add or the load is removed.
+     */
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_addi_tl(t1, cpu_sp, 1);
+    gen_data_load(ctx, Rd, t1);
+    tcg_gen_mov_tl(cpu_sp, t1);
+
+    return true;
+}
+
+/*
+ *  This instruction stores the contents of register Rr on the STACK. The
+ *  Stack Pointer is post-decremented by 1 after the PUSH.  This instruction is
+ *  not available in all devices. Refer to the device specific instruction set
+ *  summary.
+ */
+static bool trans_PUSH(DisasContext *ctx, arg_PUSH *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    gen_data_store(ctx, Rd, cpu_sp);
+    tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+    return true;
+}
+
+/*
+ *  Relative call to an address within PC - 2K + 1 and PC + 2K (words). The
+ *  return address (the instruction after the RCALL) is stored onto the Stack.
+ *  See also CALL. For AVR microcontrollers with Program memory not exceeding 4K
+ *  words (8KB) this instruction can address the entire memory from every
+ *  address location. The Stack Pointer uses a post-decrement scheme during
+ *  RCALL.
+ */
+static bool trans_RCALL(DisasContext *ctx, arg_RCALL *a)
+{
+    int ret = ctx->npc;
+    int dst = ctx->npc + a->imm;
+
+    gen_push_ret(ctx, ret);
+    gen_goto_tb(ctx, 0, dst);
+
+    return true;
+}
+
+/*
+ *  Returns from subroutine. The return address is loaded from the STACK.
+ *  The Stack Pointer uses a preincrement scheme during RET.
+ */
+static bool trans_RET(DisasContext *ctx, arg_RET *a)
+{
+    gen_pop_ret(ctx, cpu_pc);
+
+    ctx->bstate = DISAS_LOOKUP;
+    return true;
+}
+
+/*
+ *  Returns from interrupt. The return address is loaded from the STACK and
+ *  the Global Interrupt Flag is set.  Note that the Status Register is not
+ *  automatically stored when entering an interrupt routine, and it is not
+ *  restored when returning from an interrupt routine. This must be handled by
+ *  the application program. The Stack Pointer uses a pre-increment scheme
+ *  during RETI.
+ */
+static bool trans_RETI(DisasContext *ctx, arg_RETI *a)
+{
+    gen_pop_ret(ctx, cpu_pc);
+    tcg_gen_movi_tl(cpu_If, 1);
+
+    /* Need to return to main loop to re-evaluate interrupts.  */
+    ctx->bstate = DISAS_EXIT;
+    return true;
+}
+
+/*
+ *  Relative jump to an address within PC - 2K +1 and PC + 2K (words). For
+ *  AVR microcontrollers with Program memory not exceeding 4K words (8KB) this
+ *  instruction can address the entire memory from every address location. See
+ *  also JMP.
+ */
+static bool trans_RJMP(DisasContext *ctx, arg_RJMP *a)
+{
+    int dst = ctx->npc + a->imm;
+
+    gen_goto_tb(ctx, 0, dst);
+
+    return true;
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. The C Flag is shifted into
+ *  bit 7 of Rd. Bit 0 is shifted into the C Flag.  This operation, combined
+ *  with ASR, effectively divides multi-byte signed values by two. Combined with
+ *  LSR it effectively divides multi-byte unsigned values by two. The Carry Flag
+ *  can be used to round the result.
+ */
+static bool trans_ROR(DisasContext *ctx, arg_ROR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_shli_tl(t0, cpu_Cf, 7);
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1);
+    tcg_gen_shri_tl(Rd, Rd, 1);
+    tcg_gen_or_tl(Rd, Rd, t0);
+
+    gen_rshift_ZNVSf(Rd);
+
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  Subtracts two registers and subtracts with the C Flag and places the
+ *  result in the destination register Rd.
+ */
+static bool trans_SBC(DisasContext *ctx, arg_SBC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_or_tl(cpu_Zf, cpu_Zf, R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  SBCI -- Subtract Immediate with Carry
+ */
+static bool trans_SBCI(DisasContext *ctx, arg_SBCI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = tcg_const_i32(a->imm);
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_or_tl(cpu_Zf, cpu_Zf, R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  Sets a specified bit in an I/O Register. This instruction operates on
+ *  the lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBI(DisasContext *ctx, arg_SBI *a)
+{
+    TCGv data = tcg_temp_new_i32();
+    TCGv port = tcg_const_i32(a->reg);
+
+    gen_helper_inb(data, cpu_env, port);
+    tcg_gen_ori_tl(data, data, 1 << a->bit);
+    gen_helper_outb(cpu_env, port, data);
+
+    tcg_temp_free_i32(port);
+    tcg_temp_free_i32(data);
+
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in an I/O Register and skips the
+ *  next instruction if the bit is cleared. This instruction operates on the
+ *  lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBIC(DisasContext *ctx, arg_SBIC *a)
+{
+    TCGv temp = tcg_const_i32(a->reg);
+
+    gen_helper_inb(temp, cpu_env, temp);
+    tcg_gen_andi_tl(temp, temp, 1 << a->bit);
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = temp;
+    ctx->free_skip_var0 = true;
+
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in an I/O Register and skips the
+ *  next instruction if the bit is set. This instruction operates on the lower
+ *  32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBIS(DisasContext *ctx, arg_SBIS *a)
+{
+    TCGv temp = tcg_const_i32(a->reg);
+
+    gen_helper_inb(temp, cpu_env, temp);
+    tcg_gen_andi_tl(temp, temp, 1 << a->bit);
+    ctx->skip_cond = TCG_COND_NE;
+    ctx->skip_var0 = temp;
+    ctx->free_skip_var0 = true;
+
+    return true;
+}
+
+/*
+ *  Subtracts an immediate value (0-63) from a register pair and places the
+ *  result in the register pair. This instruction operates on the upper four
+ *  register pairs, and is well suited for operations on the Pointer Registers.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_SBIW(DisasContext *ctx, arg_SBIW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ADIW_SBIW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    int Imm = (a->imm);
+    TCGv R = tcg_temp_new_i32();
+    TCGv Rd = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_deposit_tl(Rd, RdL, RdH, 8, 8); /* Rd = RdH:RdL */
+    tcg_gen_subi_tl(R, Rd, Imm); /* R = Rd - Imm */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* Cf */
+    tcg_gen_andc_tl(cpu_Cf, R, Rd);
+    tcg_gen_shri_tl(cpu_Cf, cpu_Cf, 15); /* Cf = R & ~Rd */
+
+    /* Vf */
+    tcg_gen_andc_tl(cpu_Vf, Rd, R);
+    tcg_gen_shri_tl(cpu_Vf, cpu_Vf, 15); /* Vf = Rd & ~R */
+
+    /* Zf */
+    tcg_gen_mov_tl(cpu_Zf, R); /* Zf = R */
+
+    /* Nf */
+    tcg_gen_shri_tl(cpu_Nf, R, 15); /* Nf = R(15) */
+
+    /* Sf */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+
+    /* R */
+    tcg_gen_andi_tl(RdL, R, 0xff);
+    tcg_gen_shri_tl(RdH, R, 8);
+
+    tcg_temp_free_i32(Rd);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in a register and skips the next
+ *  instruction if the bit is cleared.
+ */
+static bool trans_SBRC(DisasContext *ctx, arg_SBRC *a)
+{
+    TCGv Rr = cpu_r[a->rr];
+
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = tcg_temp_new();
+    ctx->free_skip_var0 = true;
+
+    tcg_gen_andi_tl(ctx->skip_var0, Rr, 1 << a->bit);
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in a register and skips the next
+ *  instruction if the bit is set.
+ */
+static bool trans_SBRS(DisasContext *ctx, arg_SBRS *a)
+{
+    TCGv Rr = cpu_r[a->rr];
+
+    ctx->skip_cond = TCG_COND_NE;
+    ctx->skip_var0 = tcg_temp_new();
+    ctx->free_skip_var0 = true;
+
+    tcg_gen_andi_tl(ctx->skip_var0, Rr, 1 << a->bit);
+    return true;
+}
+
+/*
+ *  This instruction sets the circuit in sleep mode defined by the MCU
+ *  Control Register.
+ */
+static bool trans_SLEEP(DisasContext *ctx, arg_SLEEP *a)
+{
+    gen_helper_sleep(cpu_env);
+    ctx->bstate = DISAS_NORETURN;
+    return true;
+}
+
+/*
+ *  SPM can be used to erase a page in the Program memory, to write a page
+ *  in the Program memory (that is already erased), and to set Boot Loader Lock
+ *  bits. In some devices, the Program memory can be written one word at a time,
+ *  in other devices an entire page can be programmed simultaneously after first
+ *  filling a temporary page buffer. In all cases, the Program memory must be
+ *  erased one page at a time. When erasing the Program memory, the RAMPZ and
+ *  Z-register are used as page address. When writing the Program memory, the
+ *  RAMPZ and Z-register are used as page or word address, and the R1:R0
+ *  register pair is used as data(1). When setting the Boot Loader Lock bits,
+ *  the R1:R0 register pair is used as data. Refer to the device documentation
+ *  for detailed description of SPM usage. This instruction can address the
+ *  entire Program memory.  The SPM instruction is not available in all devices.
+ *  Refer to the device specific instruction set summary.  Note: 1. R1
+ *  determines the instruction high byte, and R0 determines the instruction low
+ *  byte.
+ */
+static bool trans_SPM(DisasContext *ctx, arg_SPM *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_SPM)) {
+        return true;
+    }
+
+    return true;
+}
+
+static bool trans_SPMX(DisasContext *ctx, arg_SPMX *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_SPMX)) {
+        return true;
+    }
+
+    return true;
+}
+
+static bool trans_STX1(DisasContext *ctx, arg_STX1 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STX2(DisasContext *ctx, arg_STX2 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STX3(DisasContext *ctx, arg_STX3 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STY2(DisasContext *ctx, arg_STY2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STY3(DisasContext *ctx, arg_STY3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STDY(DisasContext *ctx, arg_STDY *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STZ2(DisasContext *ctx, arg_STZ2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STZ3(DisasContext *ctx, arg_STZ3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STDZ(DisasContext *ctx, arg_STDZ *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Stores one byte from a Register to the data space. For parts with SRAM,
+ *  the data space consists of the Register File, I/O memory and internal SRAM
+ *  (and external SRAM if applicable). For parts without SRAM, the data space
+ *  consists of the Register File only. The EEPROM has a separate address space.
+ *  A 16-bit address must be supplied. Memory access is limited to the current
+ *  data segment of 64KB. The STS instruction uses the RAMPD Register to access
+ *  memory above 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPD in register in the I/O area has to be changed.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_STS(DisasContext *ctx, arg_STS *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_rampD;
+    a->imm = next_word(ctx);
+
+    tcg_gen_mov_tl(addr, H); /* addr = H:M:L */
+    tcg_gen_shli_tl(addr, addr, 16);
+    tcg_gen_ori_tl(addr, addr, a->imm);
+
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Subtracts two registers and places the result in the destination
+ *  register Rd.
+ */
+static bool trans_SUB(DisasContext *ctx, arg_SUB *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Subtracts a register and a constant and places the result in the
+ *  destination register Rd. This instruction is working on Register R16 to R31
+ *  and is very well suited for operations on the X, Y, and Z-pointers.
+ */
+static bool trans_SUBI(DisasContext *ctx, arg_SUBI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = tcg_const_i32(a->imm);
+    TCGv R = tcg_temp_new_i32();
+
+    /* op */
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Imm */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* R */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  Swaps high and low nibbles in a register.
+ */
+static bool trans_SWAP(DisasContext *ctx, arg_SWAP *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_andi_tl(t0, Rd, 0x0f);
+    tcg_gen_shli_tl(t0, t0, 4);
+    tcg_gen_andi_tl(t1, Rd, 0xf0);
+    tcg_gen_shri_tl(t1, t1, 4);
+    tcg_gen_or_tl(Rd, t0, t1);
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  This instruction resets the Watchdog Timer. This instruction must be
+ *  executed within a limited time given by the WD prescaler. See the Watchdog
+ *  Timer hardware specification.
+ */
+static bool trans_WDR(DisasContext *ctx, arg_WDR *a)
+{
+    gen_helper_wdr(cpu_env);
+
+    return true;
+}
+
+/*
+ *  Exchanges one byte indirect between register and data space.  The data
+ *  location is pointed to by the Z (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPZ in register in the I/O area has to be changed.  The Z-pointer Register
+ *  is left unchanged by the operation. This instruction is especially suited
+ *  for writing/reading status bits stored in SRAM.
+ */
+static bool trans_XCH(DisasContext *ctx, arg_XCH *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_load(ctx, t0, addr);
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_mov_tl(Rd, t0);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+void avr_cpu_tcg_init(void)
+{
+    int i;
+
+#define AVR_REG_OFFS(x) offsetof(CPUAVRState, x)
+    cpu_pc = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(pc_w), "pc");
+    cpu_Cf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregC), "Cf");
+    cpu_Zf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregZ), "Zf");
+    cpu_Nf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregN), "Nf");
+    cpu_Vf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregV), "Vf");
+    cpu_Sf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregS), "Sf");
+    cpu_Hf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregH), "Hf");
+    cpu_Tf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregT), "Tf");
+    cpu_If = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregI), "If");
+    cpu_rampD = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampD), "rampD");
+    cpu_rampX = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampX), "rampX");
+    cpu_rampY = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampY), "rampY");
+    cpu_rampZ = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampZ), "rampZ");
+    cpu_eind = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(eind), "eind");
+    cpu_sp = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sp), "sp");
+    cpu_skip = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(skip), "skip");
+
+    for (i = 0; i < NO_CPU_REGISTERS; i++) {
+        cpu_r[i] = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(r[i]),
+                                          reg_names[i]);
+    }
+#undef AVR_REG_OFFS
+}
+
+static void translate(DisasContext *ctx)
+{
+    uint32_t opcode = next_word(ctx);
+
+    if (!decode_insn(ctx, opcode)) {
+        gen_helper_unsupported(cpu_env);
+        ctx->bstate = DISAS_NORETURN;
+    }
+}
+
+/* Standardize the cpu_skip condition to NE.  */
+static bool canonicalize_skip(DisasContext *ctx)
+{
+    switch (ctx->skip_cond) {
+    case TCG_COND_NEVER:
+        /* Normal case: cpu_skip is known to be false.  */
+        return false;
+
+    case TCG_COND_ALWAYS:
+        /*
+         * Breakpoint case: cpu_skip is known to be true, via TB_FLAGS_SKIP.
+         * The breakpoint is on the instruction being skipped, at the start
+         * of the TranslationBlock.  No need to update.
+         */
+        return false;
+
+    case TCG_COND_NE:
+        if (ctx->skip_var1 == NULL) {
+            tcg_gen_mov_tl(cpu_skip, ctx->skip_var0);
+        } else {
+            tcg_gen_xor_tl(cpu_skip, ctx->skip_var0, ctx->skip_var1);
+            ctx->skip_var1 = NULL;
+        }
+        break;
+
+    default:
+        /* Convert to a NE condition vs 0. */
+        if (ctx->skip_var1 == NULL) {
+            tcg_gen_setcondi_tl(ctx->skip_cond, cpu_skip, ctx->skip_var0, 0);
+        } else {
+            tcg_gen_setcond_tl(ctx->skip_cond, cpu_skip,
+                               ctx->skip_var0, ctx->skip_var1);
+            ctx->skip_var1 = NULL;
+        }
+        ctx->skip_cond = TCG_COND_NE;
+        break;
+    }
+    if (ctx->free_skip_var0) {
+        tcg_temp_free(ctx->skip_var0);
+        ctx->free_skip_var0 = false;
+    }
+    ctx->skip_var0 = cpu_skip;
+    return true;
+}
+
+void gen_intermediate_code(CPUState *cs, TranslationBlock *tb, int max_insns)
+{
+    CPUAVRState *env = cs->env_ptr;
+    DisasContext ctx = {
+        .tb = tb,
+        .cs = cs,
+        .env = env,
+        .memidx = 0,
+        .bstate = DISAS_NEXT,
+        .skip_cond = TCG_COND_NEVER,
+        .singlestep = cs->singlestep_enabled,
+    };
+    target_ulong pc_start = tb->pc / 2;
+    int num_insns = 0;
+
+    if (tb->flags & TB_FLAGS_FULL_ACCESS) {
+        /*
+         * This flag is set by ST/LD instruction we will regenerate it ONLY
+         * with mem/cpu memory access instead of mem access
+         */
+        max_insns = 1;
+    }
+    if (ctx.singlestep) {
+        max_insns = 1;
+    }
+
+    gen_tb_start(tb);
+
+    ctx.npc = pc_start;
+    if (tb->flags & TB_FLAGS_SKIP) {
+        ctx.skip_cond = TCG_COND_ALWAYS;
+        ctx.skip_var0 = cpu_skip;
+    }
+
+    do {
+        TCGLabel *skip_label = NULL;
+
+        /* translate current instruction */
+        tcg_gen_insn_start(ctx.npc);
+        num_insns++;
+
+        /*
+         * this is due to some strange GDB behavior
+         * let's assume main has address 0x100
+         * b main   - sets breakpoint at address 0x00000100 (code)
+         * b *0x100 - sets breakpoint at address 0x00800100 (data)
+         */
+        if (unlikely(!ctx.singlestep &&
+                (cpu_breakpoint_test(cs, OFFSET_CODE + ctx.npc * 2, BP_ANY) ||
+                 cpu_breakpoint_test(cs, OFFSET_DATA + ctx.npc * 2, BP_ANY)))) {
+            canonicalize_skip(&ctx);
+            tcg_gen_movi_tl(cpu_pc, ctx.npc);
+            gen_helper_debug(cpu_env);
+            goto done_generating;
+        }
+
+        /* Conditionally skip the next instruction, if indicated.  */
+        if (ctx.skip_cond != TCG_COND_NEVER) {
+            skip_label = gen_new_label();
+            if (ctx.skip_var0 == cpu_skip) {
+                /*
+                 * Copy cpu_skip so that we may zero it before the branch.
+                 * This ensures that cpu_skip is non-zero after the label
+                 * if and only if the skipped insn itself sets a skip.
+                 */
+                ctx.free_skip_var0 = true;
+                ctx.skip_var0 = tcg_temp_new();
+                tcg_gen_mov_tl(ctx.skip_var0, cpu_skip);
+                tcg_gen_movi_tl(cpu_skip, 0);
+            }
+            if (ctx.skip_var1 == NULL) {
+                tcg_gen_brcondi_tl(ctx.skip_cond, ctx.skip_var0, 0, skip_label);
+            } else {
+                tcg_gen_brcond_tl(ctx.skip_cond, ctx.skip_var0,
+                                  ctx.skip_var1, skip_label);
+                ctx.skip_var1 = NULL;
+            }
+            if (ctx.free_skip_var0) {
+                tcg_temp_free(ctx.skip_var0);
+                ctx.free_skip_var0 = false;
+            }
+            ctx.skip_cond = TCG_COND_NEVER;
+            ctx.skip_var0 = NULL;
+        }
+
+        translate(&ctx);
+
+        if (skip_label) {
+            canonicalize_skip(&ctx);
+            gen_set_label(skip_label);
+            if (ctx.bstate == DISAS_NORETURN) {
+                ctx.bstate = DISAS_CHAIN;
+            }
+        }
+    } while (ctx.bstate == DISAS_NEXT
+             && num_insns < max_insns
+             && (ctx.npc - pc_start) * 2 < TARGET_PAGE_SIZE - 4
+             && !tcg_op_buf_full());
+
+    if (tb->cflags & CF_LAST_IO) {
+        gen_io_end();
+    }
+
+    bool nonconst_skip = canonicalize_skip(&ctx);
+
+    switch (ctx.bstate) {
+    case DISAS_NORETURN:
+        assert(!nonconst_skip);
+        break;
+    case DISAS_NEXT:
+    case DISAS_TOO_MANY:
+    case DISAS_CHAIN:
+        if (!nonconst_skip) {
+            /* Note gen_goto_tb checks singlestep.  */
+            gen_goto_tb(&ctx, 1, ctx.npc);
+            break;
+        }
+        tcg_gen_movi_tl(cpu_pc, ctx.npc);
+        /* fall through */
+    case DISAS_LOOKUP:
+        if (!ctx.singlestep) {
+            tcg_gen_lookup_and_goto_ptr();
+            break;
+        }
+        /* fall through */
+    case DISAS_EXIT:
+        if (ctx.singlestep) {
+            gen_helper_debug(cpu_env);
+        } else {
+            tcg_gen_exit_tb(NULL, 0);
+        }
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+done_generating:
+    gen_tb_end(tb, num_insns);
+
+    tb->size = (ctx.npc - pc_start) * 2;
+    tb->icount = num_insns;
+}
+
+void restore_state_to_opc(CPUAVRState *env, TranslationBlock *tb,
+                            target_ulong *data)
+{
+    env->pc_w = data[0];
+}
-- 
2.17.2 (Apple Git-113)



  parent reply index

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-24 18:46 [Qemu-devel] [PATCH v29 0/8] QEMU AVR 8 bit cores Michael Rolnik
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 1/8] target/avr: Add outward facing interfaces and core CPU logic Michael Rolnik
2019-08-26  7:21   ` Thomas Huth
2019-08-26  7:53     ` Michael Rolnik
2019-08-26  8:00       ` Thomas Huth
2019-08-27 10:59         ` Sarah Harris
2019-10-12  7:22           ` Philippe Mathieu-Daudé
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 2/8] target/avr: Add instruction helpers Michael Rolnik
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 3/8] target/avr: Add instruction decoding Michael Rolnik
2019-08-24 18:46 ` Michael Rolnik [this message]
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 5/8] target/avr: Add limited support for USART and 16 bit timer peripherals Michael Rolnik
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 6/8] target/avr: Add example board configuration Michael Rolnik
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 7/8] target/avr: Register AVR support with the rest of QEMU, the build system, and the MAINTAINERS file Michael Rolnik
2019-08-26  6:01   ` Thomas Huth
2019-08-24 18:46 ` [Qemu-devel] [PATCH v29 8/8] target/avr: Add tests Michael Rolnik
2019-08-26  5:39   ` Thomas Huth
2019-08-26  9:23   ` Alex Bennée
2019-08-26 17:13     ` Richard Henderson
2019-08-27  9:25       ` Alex Bennée
2019-08-27  9:29         ` Pavel Dovgalyuk
2019-10-12  7:17           ` Philippe Mathieu-Daudé
2019-10-12 14:11             ` Pavel Dovgalyuk
2019-08-26  7:09 ` [Qemu-devel] [PATCH v29 0/8] QEMU AVR 8 bit cores Pavel Dovgalyuk
2019-08-26  7:46   ` Michael Rolnik

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