1 /* 2 * emulator main execution loop 3 * 4 * Copyright (c) 2003-2005 Fabrice Bellard 5 * 6 * This library is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * This library is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with this library; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "exec/log.h" 22 #include "system/tcg.h" 23 #include "qemu/plugin.h" 24 #include "internal-common.h" 25 26 bool tcg_allowed; 27 28 bool tcg_cflags_has(CPUState *cpu, uint32_t flags) 29 { 30 return cpu->tcg_cflags & flags; 31 } 32 33 void tcg_cflags_set(CPUState *cpu, uint32_t flags) 34 { 35 cpu->tcg_cflags |= flags; 36 } 37 38 uint32_t curr_cflags(CPUState *cpu) 39 { 40 uint32_t cflags = cpu->tcg_cflags; 41 42 /* 43 * Record gdb single-step. We should be exiting the TB by raising 44 * EXCP_DEBUG, but to simplify other tests, disable chaining too. 45 * 46 * For singlestep and -d nochain, suppress goto_tb so that 47 * we can log -d cpu,exec after every TB. 48 */ 49 if (unlikely(cpu->singlestep_enabled)) { 50 cflags |= CF_NO_GOTO_TB | CF_NO_GOTO_PTR | CF_SINGLE_STEP | 1; 51 } else if (qatomic_read(&one_insn_per_tb)) { 52 cflags |= CF_NO_GOTO_TB | 1; 53 } else if (qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { 54 cflags |= CF_NO_GOTO_TB; 55 } 56 57 return cflags; 58 } 59 60 /* exit the current TB, but without causing any exception to be raised */ 61 void cpu_loop_exit_noexc(CPUState *cpu) 62 { 63 cpu->exception_index = -1; 64 cpu_loop_exit(cpu); 65 } 66 67 void cpu_loop_exit(CPUState *cpu) 68 { 69 /* Undo the setting in cpu_tb_exec. */ 70 cpu->neg.can_do_io = true; 71 /* Undo any setting in generated code. */ 72 qemu_plugin_disable_mem_helpers(cpu); 73 siglongjmp(cpu->jmp_env, 1); 74 } 75 76 void cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc) 77 { 78 if (pc) { 79 cpu_restore_state(cpu, pc); 80 } 81 cpu_loop_exit(cpu); 82 } 83 84 void cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc) 85 { 86 /* Prevent looping if already executing in a serial context. */ 87 g_assert(!cpu_in_serial_context(cpu)); 88 cpu->exception_index = EXCP_ATOMIC; 89 cpu_loop_exit_restore(cpu, pc); 90 } 91