Re: [PATCH v32 04/13] target/avr: Add instruction translation - Registers definition

[Michael Rolnik]

On Thu, Oct 17, 2019 at 8:25 PM Aleksandar Markovic
<address@hidden> wrote:
>
>
>
> On Monday, October 14, 2019, Michael Rolnik <address@hidden> wrote:
>>
>> Signed-off-by: Michael Rolnik <address@hidden>
>> ---
>>  target/avr/translate.c | 132 +++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 132 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..53c9892a60
>> --- /dev/null
>> +++ b/target/avr/translate.c
>> @@ -0,0 +1,132 @@
>> +/*
>> + * 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"
>> +#include "exec/gen-icount.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;
>> +
>
>
> Hello, Michael,
>
> Is there any particular reason or motivation beyond modelling status register 
> flags as TCGv variables?
I think it's easier this way as I don't need to convert flag values to
bits or bits to flag values.
>
> A.
>
>
>
>>
>> +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 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 bool decode_insn(DisasContext *ctx, uint16_t insn);
>> +#include "decode_insn.inc.c"
>> +
>> --
>> 2.17.2 (Apple Git-113)
>>


-- 
Best Regards,
Michael Rolnik