#ifndef GEN_ICOUNT_H #define GEN_ICOUNT_H #include "qemu/timer.h" /* Helpers for instruction counting code generation. */ static TCGOp *icount_start_insn; static inline void gen_io_start(void) { TCGv_i32 tmp = tcg_const_i32(1); tcg_gen_st_i32(tmp, cpu_env, offsetof(ArchCPU, parent_obj.can_do_io) - offsetof(ArchCPU, env)); tcg_temp_free_i32(tmp); } /* * cpu->can_do_io is cleared automatically at the beginning of * each translation block. The cost is minimal and only paid * for -icount, plus it would be very easy to forget doing it * in the translator. Therefore, backends only need to call * gen_io_start. */ static inline void gen_io_end(void) { TCGv_i32 tmp = tcg_const_i32(0); tcg_gen_st_i32(tmp, cpu_env, offsetof(ArchCPU, parent_obj.can_do_io) - offsetof(ArchCPU, env)); tcg_temp_free_i32(tmp); } static inline void gen_tb_start(TranslationBlock *tb) { TCGv_i32 count, imm; tcg_ctx->exitreq_label = gen_new_label(); if (tb_cflags(tb) & CF_USE_ICOUNT) { count = tcg_temp_local_new_i32(); } else { count = tcg_temp_new_i32(); } tcg_gen_ld_i32(count, cpu_env, offsetof(ArchCPU, neg.icount_decr.u32) - offsetof(ArchCPU, env)); if (tb_cflags(tb) & CF_USE_ICOUNT) { imm = tcg_temp_new_i32(); /* We emit a movi with a dummy immediate argument. Keep the insn index * of the movi so that we later (when we know the actual insn count) * can update the immediate argument with the actual insn count. */ tcg_gen_movi_i32(imm, 0xdeadbeef); icount_start_insn = tcg_last_op(); tcg_gen_sub_i32(count, count, imm); tcg_temp_free_i32(imm); } tcg_gen_brcondi_i32(TCG_COND_LT, count, 0, tcg_ctx->exitreq_label); if (tb_cflags(tb) & CF_USE_ICOUNT) { tcg_gen_st16_i32(count, cpu_env, offsetof(ArchCPU, neg.icount_decr.u16.low) - offsetof(ArchCPU, env)); gen_io_end(); } tcg_temp_free_i32(count); } static inline void gen_tb_end(TranslationBlock *tb, int num_insns) { if (tb_cflags(tb) & CF_USE_ICOUNT) { /* Update the num_insn immediate parameter now that we know * the actual insn count. */ tcg_set_insn_param(icount_start_insn, 1, num_insns); } gen_set_label(tcg_ctx->exitreq_label); tcg_gen_exit_tb(tb, TB_EXIT_REQUESTED); } #endif