Re: [Qemu-devel] [PATCH v7 1/4] Add moxie target code

[Peter Maydell]

On 3 March 2013 21:07, Anthony Green <address@hidden> wrote:
> +/* generate intermediate code for basic block 'tb'.  */
> +static void
> +gen_intermediate_code_internal(MoxieCPU *cpu, TranslationBlock *tb,
> +                               bool search_pc)
> +{
> +    DisasContext ctx;
> +    target_ulong pc_start;
> +    uint16_t *gen_opc_end;
> +    CPUBreakpoint *bp;
> +    int j, lj = -1;
> +    CPUMoxieState *env = &cpu->env;
> +
> +    pc_start = tb->pc;
> +    gen_opc_end = tcg_ctx.gen_opc_buf + OPC_MAX_SIZE;
> +    ctx.pc = pc_start;
> +    ctx.saved_pc = -1;
> +    ctx.tb = tb;
> +    ctx.memidx = 0;
> +    ctx.singlestep_enabled = 0;
> +    ctx.bstate = BS_NONE;
> +
> +    do {
> +        if (unlikely(!QTAILQ_EMPTY(&env->breakpoints))) {
> +            QTAILQ_FOREACH(bp, &env->breakpoints, entry) {
> +                if (ctx.pc == bp->pc) {
> +                    tcg_gen_movi_i32(cpu_pc, ctx.pc);
> +                    gen_helper_debug(cpu_env);
> +                    ctx.bstate = BS_EXCP;
> +                    goto done_generating;
> +                }
> +            }
> +        }
> +
> +        if (search_pc) {
> +            j = tcg_ctx.gen_opc_ptr - tcg_ctx.gen_opc_buf;
> +            if (lj < j) {
> +                lj++;
> +                while (lj < j) {
> +                    tcg_ctx.gen_opc_instr_start[lj++] = 0;
> +                }
> +            }
> +            tcg_ctx.gen_opc_pc[lj] = ctx.pc;
> +            tcg_ctx.gen_opc_instr_start[lj] = 1;
> +        }
> +        ctx.opcode = cpu_lduw_code(env, ctx.pc);
> +        ctx.pc += decode_opc(cpu, &ctx);
> +
> +        if (env->singlestep_enabled) {
> +            break;
> +        }
> +
> +        if ((ctx.pc & (TARGET_PAGE_SIZE - 1)) == 0) {
> +            break;
> +        }
> +    } while (ctx.bstate == BS_NONE && tcg_ctx.gen_opc_ptr < gen_opc_end);
> +
> +    if (env->singlestep_enabled) {
> +        tcg_gen_movi_tl(cpu_pc, ctx.pc);
> +        gen_helper_debug(cpu_env);
> +    } else {
> +        switch (ctx.bstate) {
> +        case BS_STOP:
> +        case BS_NONE:
> +            gen_goto_tb(env, &ctx, 0, ctx.pc);
> +            break;
> +        case BS_EXCP:
> +            tcg_gen_exit_tb(0);
> +            break;
> +        case BS_BRANCH:
> +        default:
> +            break;
> +        }
> +    }
> + done_generating:
> +    *tcg_ctx.gen_opc_ptr = INDEX_op_end;
> +    if (search_pc) {
> +        j = tcg_ctx.gen_opc_ptr - tcg_ctx.gen_opc_buf;
> +        lj++;
> +        while (lj <= j) {
> +            tcg_ctx.gen_opc_instr_start[lj++] = 0;
> +        }
> +    } else {
> +        tb->size = ctx.pc - pc_start;
> +    }
> +}

Now that my 'get rid of cpu_tb_unlink()' patch series has been
applied, you must call 'gen_tb_start()' and 'gen_tb_end()' in
the right places in this function, or interrupts will not be
able to stop QEMU executing translated code.

thanks
-- PMM