Track direct jumps via dc->jmp_pc_imm. Use that in preference to jmp_pc when possible. Emit goto_tb in that case, and lookup_and_goto_tb otherwise.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- target/openrisc/translate.c | 82 +++++++++++++++++++++---------------- 1 file changed, 46 insertions(+), 36 deletions(-) diff --git a/target/openrisc/translate.c b/target/openrisc/translate.c index e566be6d3c..a8afb9a562 100644 --- a/target/openrisc/translate.c +++ b/target/openrisc/translate.c @@ -42,13 +42,16 @@ /* is_jmp field values */ #define DISAS_EXIT DISAS_TARGET_0 /* force exit to main loop */ -#define DISAS_UPDATE DISAS_TARGET_1 /* cpu state was modified dynamically */ +#define DISAS_JUMP DISAS_TARGET_1 /* exit via jmp_pc/jmp_pc_imm */ typedef struct DisasContext { DisasContextBase base; uint32_t mem_idx; uint32_t tb_flags; uint32_t delayed_branch; + + /* If not -1, jmp_pc contains this value and so is a direct jump. */ + target_ulong jmp_pc_imm; } DisasContext; /* Include the auto-generated decoder. */ @@ -164,34 +167,6 @@ static void check_ov64s(DisasContext *dc) } \ } while (0) -static inline bool use_goto_tb(DisasContext *dc, target_ulong dest) -{ - if (unlikely(dc->base.singlestep_enabled)) { - return false; - } - -#ifndef CONFIG_USER_ONLY - return (dc->base.tb->pc & TARGET_PAGE_MASK) == (dest & TARGET_PAGE_MASK); -#else - return true; -#endif -} - -static void gen_goto_tb(DisasContext *dc, int n, target_ulong dest) -{ - if (use_goto_tb(dc, dest)) { - tcg_gen_movi_tl(cpu_pc, dest); - tcg_gen_goto_tb(n); - tcg_gen_exit_tb((uintptr_t)dc->base.tb + n); - } else { - tcg_gen_movi_tl(cpu_pc, dest); - if (dc->base.singlestep_enabled) { - gen_exception(dc, EXCP_DEBUG); - } - tcg_gen_exit_tb(0); - } -} - static void gen_ove_cy(DisasContext *dc) { if (dc->tb_flags & SR_OVE) { @@ -655,6 +630,7 @@ static bool trans_l_j(DisasContext *dc, arg_l_j *a, uint32_t insn) LOG_DIS("l.j %d\n", a->n); tcg_gen_movi_tl(jmp_pc, tmp_pc); + dc->jmp_pc_imm = tmp_pc; dc->delayed_branch = 2; return true; } @@ -669,6 +645,7 @@ static bool trans_l_jal(DisasContext *dc, arg_l_jal *a, uint32_t insn) /* Optimize jal being used to load the PC for PIC. */ if (tmp_pc != ret_pc) { tcg_gen_movi_tl(jmp_pc, tmp_pc); + dc->jmp_pc_imm = tmp_pc; dc->delayed_branch = 2; } return true; @@ -1381,6 +1358,8 @@ static void openrisc_tr_init_disas_context(DisasContextBase *dcb, CPUState *cs) dc->mem_idx = cpu_mmu_index(env, false); dc->tb_flags = dc->base.tb->flags; dc->delayed_branch = (dc->tb_flags & TB_FLAGS_DFLAG) != 0; + dc->jmp_pc_imm = -1; + bound = -(dc->base.pc_first | TARGET_PAGE_MASK) / 4; dc->base.max_insns = MIN(dc->base.max_insns, bound); } @@ -1437,10 +1416,7 @@ static void openrisc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs) if (dc->delayed_branch) { dc->delayed_branch--; if (!dc->delayed_branch) { - tcg_gen_mov_tl(cpu_pc, jmp_pc); - tcg_gen_discard_tl(jmp_pc); - dc->base.is_jmp = DISAS_UPDATE; - return; + dc->base.is_jmp = DISAS_JUMP; } } } @@ -1448,22 +1424,56 @@ static void openrisc_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs) static void openrisc_tr_tb_stop(DisasContextBase *dcbase, CPUState *cs) { DisasContext *dc = container_of(dcbase, DisasContext, base); + target_ulong jmp_dest; /* If we have already exited the TB, nothing following has effect. */ if (dc->base.is_jmp == DISAS_NORETURN) { return; } + /* Adjust the delayed branch state for the next TB. */ if ((dc->tb_flags & TB_FLAGS_DFLAG ? 1 : 0) != (dc->delayed_branch != 0)) { tcg_gen_movi_i32(cpu_dflag, dc->delayed_branch != 0); } - tcg_gen_movi_tl(cpu_ppc, dc->base.pc_next - 4); + /* For DISAS_TOO_MANY, jump to the next insn. */ + jmp_dest = dc->base.pc_next; + tcg_gen_movi_tl(cpu_ppc, jmp_dest - 4); + switch (dc->base.is_jmp) { + case DISAS_JUMP: + jmp_dest = dc->jmp_pc_imm; + if (jmp_dest == -1) { + /* The jump destination is indirect/computed; use jmp_pc. */ + tcg_gen_mov_tl(cpu_pc, jmp_pc); + tcg_gen_discard_tl(jmp_pc); + if (unlikely(dc->base.singlestep_enabled)) { + gen_exception(dc, EXCP_DEBUG); + } else { + tcg_gen_lookup_and_goto_ptr (); + } + break; + } + /* The jump destination is direct; use jmp_pc_imm. + However, we will have stored into jmp_pc as well; + we know now that it wasn't needed. */ + tcg_gen_discard_tl(jmp_pc); + /* fallthru */ + case DISAS_TOO_MANY: - gen_goto_tb(dc, 0, dc->base.pc_next); + if (unlikely(dc->base.singlestep_enabled)) { + tcg_gen_movi_tl(cpu_pc, jmp_dest); + gen_exception(dc, EXCP_DEBUG); + } else if ((dc->base.pc_first ^ jmp_dest) & TARGET_PAGE_MASK) { + tcg_gen_movi_tl(cpu_pc, jmp_dest); + tcg_gen_lookup_and_goto_ptr (); + } else { + tcg_gen_goto_tb(0); + tcg_gen_movi_tl(cpu_pc, jmp_dest); + tcg_gen_exit_tb((uintptr_t)dc->base.tb + 0); + } break; - case DISAS_UPDATE: + case DISAS_EXIT: if (unlikely(dc->base.singlestep_enabled)) { gen_exception(dc, EXCP_DEBUG); -- 2.17.0