From 9baade8d3be8506daa9962ce54d39e25b2b220f1 Mon Sep 17 00:00:00 2001 From: Michael Rolnik Date: Fri, 24 Jan 2020 01:51:15 +0100 Subject: [PATCH] target/avr: Add instruction translation - CPU main translation function MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add the core of translation mechanism. Co-developed-by: Richard Henderson Co-developed-by: Michael Rolnik Signed-off-by: Michael Rolnik Signed-off-by: Richard Henderson Signed-off-by: Aleksandar Markovic Tested-by: Philippe Mathieu-Daudé Reviewed-by: Aleksandar Markovic Signed-off-by: Thomas Huth Message-Id: <20200705140315.260514-17-huth@tuxfamily.org> Signed-off-by: Philippe Mathieu-Daudé --- target/avr/translate.c | 213 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 213 insertions(+) diff --git a/target/avr/translate.c b/target/avr/translate.c index ee7811995a81..7ad3dec0315b 100644 --- a/target/avr/translate.c +++ b/target/avr/translate.c @@ -2805,3 +2805,216 @@ static bool trans_WDR(DisasContext *ctx, arg_WDR *a) return true; } + +/* + * Core translation mechanism functions: + * + * - translate() + * - canonicalize_skip() + * - gen_intermediate_code() + * - restore_state_to_opc() + * + */ +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]; +}