| /* |
| * emulator main execution loop |
| * |
| * Copyright (c) 2003-2005 Fabrice Bellard |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| #include "config.h" |
| #include "cpu.h" |
| #include "disas/disas.h" |
| #include "tcg.h" |
| #include "qemu/atomic.h" |
| #include "sysemu/qtest.h" |
| |
| //#define CONFIG_DEBUG_EXEC |
| |
| bool qemu_cpu_has_work(CPUState *cpu) |
| { |
| return cpu_has_work(cpu); |
| } |
| |
| void cpu_loop_exit(CPUArchState *env) |
| { |
| CPUState *cpu = ENV_GET_CPU(env); |
| |
| cpu->current_tb = NULL; |
| siglongjmp(env->jmp_env, 1); |
| } |
| |
| /* exit the current TB from a signal handler. The host registers are |
| restored in a state compatible with the CPU emulator |
| */ |
| #if defined(CONFIG_SOFTMMU) |
| void cpu_resume_from_signal(CPUArchState *env, void *puc) |
| { |
| /* XXX: restore cpu registers saved in host registers */ |
| |
| env->exception_index = -1; |
| siglongjmp(env->jmp_env, 1); |
| } |
| #endif |
| |
| /* Execute a TB, and fix up the CPU state afterwards if necessary */ |
| static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu, uint8_t *tb_ptr) |
| { |
| CPUArchState *env = cpu->env_ptr; |
| tcg_target_ulong next_tb = tcg_qemu_tb_exec(env, tb_ptr); |
| if ((next_tb & TB_EXIT_MASK) > TB_EXIT_IDX1) { |
| /* We didn't start executing this TB (eg because the instruction |
| * counter hit zero); we must restore the guest PC to the address |
| * of the start of the TB. |
| */ |
| TranslationBlock *tb = (TranslationBlock *)(next_tb & ~TB_EXIT_MASK); |
| cpu_pc_from_tb(env, tb); |
| } |
| if ((next_tb & TB_EXIT_MASK) == TB_EXIT_REQUESTED) { |
| /* We were asked to stop executing TBs (probably a pending |
| * interrupt. We've now stopped, so clear the flag. |
| */ |
| cpu->tcg_exit_req = 0; |
| } |
| return next_tb; |
| } |
| |
| /* Execute the code without caching the generated code. An interpreter |
| could be used if available. */ |
| static void cpu_exec_nocache(CPUArchState *env, int max_cycles, |
| TranslationBlock *orig_tb) |
| { |
| CPUState *cpu = ENV_GET_CPU(env); |
| TranslationBlock *tb; |
| |
| /* Should never happen. |
| We only end up here when an existing TB is too long. */ |
| if (max_cycles > CF_COUNT_MASK) |
| max_cycles = CF_COUNT_MASK; |
| |
| tb = tb_gen_code(env, orig_tb->pc, orig_tb->cs_base, orig_tb->flags, |
| max_cycles); |
| cpu->current_tb = tb; |
| /* execute the generated code */ |
| cpu_tb_exec(cpu, tb->tc_ptr); |
| cpu->current_tb = NULL; |
| tb_phys_invalidate(tb, -1); |
| tb_free(tb); |
| } |
| |
| static TranslationBlock *tb_find_slow(CPUArchState *env, |
| target_ulong pc, |
| target_ulong cs_base, |
| uint64_t flags) |
| { |
| TranslationBlock *tb, **ptb1; |
| unsigned int h; |
| tb_page_addr_t phys_pc, phys_page1; |
| target_ulong virt_page2; |
| |
| tcg_ctx.tb_ctx.tb_invalidated_flag = 0; |
| |
| /* find translated block using physical mappings */ |
| phys_pc = get_page_addr_code(env, pc); |
| phys_page1 = phys_pc & TARGET_PAGE_MASK; |
| h = tb_phys_hash_func(phys_pc); |
| ptb1 = &tcg_ctx.tb_ctx.tb_phys_hash[h]; |
| for(;;) { |
| tb = *ptb1; |
| if (!tb) |
| goto not_found; |
| if (tb->pc == pc && |
| tb->page_addr[0] == phys_page1 && |
| tb->cs_base == cs_base && |
| tb->flags == flags) { |
| /* check next page if needed */ |
| if (tb->page_addr[1] != -1) { |
| tb_page_addr_t phys_page2; |
| |
| virt_page2 = (pc & TARGET_PAGE_MASK) + |
| TARGET_PAGE_SIZE; |
| phys_page2 = get_page_addr_code(env, virt_page2); |
| if (tb->page_addr[1] == phys_page2) |
| goto found; |
| } else { |
| goto found; |
| } |
| } |
| ptb1 = &tb->phys_hash_next; |
| } |
| not_found: |
| /* if no translated code available, then translate it now */ |
| tb = tb_gen_code(env, pc, cs_base, flags, 0); |
| |
| found: |
| /* Move the last found TB to the head of the list */ |
| if (likely(*ptb1)) { |
| *ptb1 = tb->phys_hash_next; |
| tb->phys_hash_next = tcg_ctx.tb_ctx.tb_phys_hash[h]; |
| tcg_ctx.tb_ctx.tb_phys_hash[h] = tb; |
| } |
| /* we add the TB in the virtual pc hash table */ |
| env->tb_jmp_cache[tb_jmp_cache_hash_func(pc)] = tb; |
| return tb; |
| } |
| |
| static inline TranslationBlock *tb_find_fast(CPUArchState *env) |
| { |
| TranslationBlock *tb; |
| target_ulong cs_base, pc; |
| int flags; |
| |
| /* we record a subset of the CPU state. It will |
| always be the same before a given translated block |
| is executed. */ |
| cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags); |
| tb = env->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]; |
| if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base || |
| tb->flags != flags)) { |
| tb = tb_find_slow(env, pc, cs_base, flags); |
| } |
| return tb; |
| } |
| |
| static CPUDebugExcpHandler *debug_excp_handler; |
| |
| void cpu_set_debug_excp_handler(CPUDebugExcpHandler *handler) |
| { |
| debug_excp_handler = handler; |
| } |
| |
| static void cpu_handle_debug_exception(CPUArchState *env) |
| { |
| CPUWatchpoint *wp; |
| |
| if (!env->watchpoint_hit) { |
| QTAILQ_FOREACH(wp, &env->watchpoints, entry) { |
| wp->flags &= ~BP_WATCHPOINT_HIT; |
| } |
| } |
| if (debug_excp_handler) { |
| debug_excp_handler(env); |
| } |
| } |
| |
| /* main execution loop */ |
| |
| volatile sig_atomic_t exit_request; |
| |
| int cpu_exec(CPUArchState *env) |
| { |
| CPUState *cpu = ENV_GET_CPU(env); |
| int ret, interrupt_request; |
| TranslationBlock *tb; |
| uint8_t *tc_ptr; |
| tcg_target_ulong next_tb; |
| |
| if (env->halted) { |
| if (!cpu_has_work(cpu)) { |
| return EXCP_HALTED; |
| } |
| |
| env->halted = 0; |
| } |
| |
| cpu_single_env = env; |
| |
| if (unlikely(exit_request)) { |
| cpu->exit_request = 1; |
| } |
| |
| #if defined(TARGET_I386) |
| /* put eflags in CPU temporary format */ |
| CC_SRC = env->eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C); |
| DF = 1 - (2 * ((env->eflags >> 10) & 1)); |
| CC_OP = CC_OP_EFLAGS; |
| env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C); |
| #elif defined(TARGET_SPARC) |
| #elif defined(TARGET_M68K) |
| env->cc_op = CC_OP_FLAGS; |
| env->cc_dest = env->sr & 0xf; |
| env->cc_x = (env->sr >> 4) & 1; |
| #elif defined(TARGET_ALPHA) |
| #elif defined(TARGET_ARM) |
| #elif defined(TARGET_UNICORE32) |
| #elif defined(TARGET_PPC) |
| env->reserve_addr = -1; |
| #elif defined(TARGET_LM32) |
| #elif defined(TARGET_MICROBLAZE) |
| #elif defined(TARGET_MIPS) |
| #elif defined(TARGET_OPENRISC) |
| #elif defined(TARGET_SH4) |
| #elif defined(TARGET_CRIS) |
| #elif defined(TARGET_S390X) |
| #elif defined(TARGET_XTENSA) |
| /* XXXXX */ |
| #else |
| #error unsupported target CPU |
| #endif |
| env->exception_index = -1; |
| |
| /* prepare setjmp context for exception handling */ |
| for(;;) { |
| if (sigsetjmp(env->jmp_env, 0) == 0) { |
| /* if an exception is pending, we execute it here */ |
| if (env->exception_index >= 0) { |
| if (env->exception_index >= EXCP_INTERRUPT) { |
| /* exit request from the cpu execution loop */ |
| ret = env->exception_index; |
| if (ret == EXCP_DEBUG) { |
| cpu_handle_debug_exception(env); |
| } |
| break; |
| } else { |
| #if defined(CONFIG_USER_ONLY) |
| /* if user mode only, we simulate a fake exception |
| which will be handled outside the cpu execution |
| loop */ |
| #if defined(TARGET_I386) |
| do_interrupt(env); |
| #endif |
| ret = env->exception_index; |
| break; |
| #else |
| do_interrupt(env); |
| env->exception_index = -1; |
| #endif |
| } |
| } |
| |
| next_tb = 0; /* force lookup of first TB */ |
| for(;;) { |
| interrupt_request = env->interrupt_request; |
| if (unlikely(interrupt_request)) { |
| if (unlikely(env->singlestep_enabled & SSTEP_NOIRQ)) { |
| /* Mask out external interrupts for this step. */ |
| interrupt_request &= ~CPU_INTERRUPT_SSTEP_MASK; |
| } |
| if (interrupt_request & CPU_INTERRUPT_DEBUG) { |
| env->interrupt_request &= ~CPU_INTERRUPT_DEBUG; |
| env->exception_index = EXCP_DEBUG; |
| cpu_loop_exit(env); |
| } |
| #if defined(TARGET_ARM) || defined(TARGET_SPARC) || defined(TARGET_MIPS) || \ |
| defined(TARGET_PPC) || defined(TARGET_ALPHA) || defined(TARGET_CRIS) || \ |
| defined(TARGET_MICROBLAZE) || defined(TARGET_LM32) || defined(TARGET_UNICORE32) |
| if (interrupt_request & CPU_INTERRUPT_HALT) { |
| env->interrupt_request &= ~CPU_INTERRUPT_HALT; |
| env->halted = 1; |
| env->exception_index = EXCP_HLT; |
| cpu_loop_exit(env); |
| } |
| #endif |
| #if defined(TARGET_I386) |
| #if !defined(CONFIG_USER_ONLY) |
| if (interrupt_request & CPU_INTERRUPT_POLL) { |
| env->interrupt_request &= ~CPU_INTERRUPT_POLL; |
| apic_poll_irq(env->apic_state); |
| } |
| #endif |
| if (interrupt_request & CPU_INTERRUPT_INIT) { |
| cpu_svm_check_intercept_param(env, SVM_EXIT_INIT, |
| 0); |
| do_cpu_init(x86_env_get_cpu(env)); |
| env->exception_index = EXCP_HALTED; |
| cpu_loop_exit(env); |
| } else if (interrupt_request & CPU_INTERRUPT_SIPI) { |
| do_cpu_sipi(x86_env_get_cpu(env)); |
| } else if (env->hflags2 & HF2_GIF_MASK) { |
| if ((interrupt_request & CPU_INTERRUPT_SMI) && |
| !(env->hflags & HF_SMM_MASK)) { |
| cpu_svm_check_intercept_param(env, SVM_EXIT_SMI, |
| 0); |
| env->interrupt_request &= ~CPU_INTERRUPT_SMI; |
| do_smm_enter(env); |
| next_tb = 0; |
| } else if ((interrupt_request & CPU_INTERRUPT_NMI) && |
| !(env->hflags2 & HF2_NMI_MASK)) { |
| env->interrupt_request &= ~CPU_INTERRUPT_NMI; |
| env->hflags2 |= HF2_NMI_MASK; |
| do_interrupt_x86_hardirq(env, EXCP02_NMI, 1); |
| next_tb = 0; |
| } else if (interrupt_request & CPU_INTERRUPT_MCE) { |
| env->interrupt_request &= ~CPU_INTERRUPT_MCE; |
| do_interrupt_x86_hardirq(env, EXCP12_MCHK, 0); |
| next_tb = 0; |
| } else if ((interrupt_request & CPU_INTERRUPT_HARD) && |
| (((env->hflags2 & HF2_VINTR_MASK) && |
| (env->hflags2 & HF2_HIF_MASK)) || |
| (!(env->hflags2 & HF2_VINTR_MASK) && |
| (env->eflags & IF_MASK && |
| !(env->hflags & HF_INHIBIT_IRQ_MASK))))) { |
| int intno; |
| cpu_svm_check_intercept_param(env, SVM_EXIT_INTR, |
| 0); |
| env->interrupt_request &= ~(CPU_INTERRUPT_HARD | CPU_INTERRUPT_VIRQ); |
| intno = cpu_get_pic_interrupt(env); |
| qemu_log_mask(CPU_LOG_TB_IN_ASM, "Servicing hardware INT=0x%02x\n", intno); |
| do_interrupt_x86_hardirq(env, intno, 1); |
| /* ensure that no TB jump will be modified as |
| the program flow was changed */ |
| next_tb = 0; |
| #if !defined(CONFIG_USER_ONLY) |
| } else if ((interrupt_request & CPU_INTERRUPT_VIRQ) && |
| (env->eflags & IF_MASK) && |
| !(env->hflags & HF_INHIBIT_IRQ_MASK)) { |
| int intno; |
| /* FIXME: this should respect TPR */ |
| cpu_svm_check_intercept_param(env, SVM_EXIT_VINTR, |
| 0); |
| intno = ldl_phys(env->vm_vmcb + offsetof(struct vmcb, control.int_vector)); |
| qemu_log_mask(CPU_LOG_TB_IN_ASM, "Servicing virtual hardware INT=0x%02x\n", intno); |
| do_interrupt_x86_hardirq(env, intno, 1); |
| env->interrupt_request &= ~CPU_INTERRUPT_VIRQ; |
| next_tb = 0; |
| #endif |
| } |
| } |
| #elif defined(TARGET_PPC) |
| if ((interrupt_request & CPU_INTERRUPT_RESET)) { |
| cpu_reset(cpu); |
| } |
| if (interrupt_request & CPU_INTERRUPT_HARD) { |
| ppc_hw_interrupt(env); |
| if (env->pending_interrupts == 0) |
| env->interrupt_request &= ~CPU_INTERRUPT_HARD; |
| next_tb = 0; |
| } |
| #elif defined(TARGET_LM32) |
| if ((interrupt_request & CPU_INTERRUPT_HARD) |
| && (env->ie & IE_IE)) { |
| env->exception_index = EXCP_IRQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_MICROBLAZE) |
| if ((interrupt_request & CPU_INTERRUPT_HARD) |
| && (env->sregs[SR_MSR] & MSR_IE) |
| && !(env->sregs[SR_MSR] & (MSR_EIP | MSR_BIP)) |
| && !(env->iflags & (D_FLAG | IMM_FLAG))) { |
| env->exception_index = EXCP_IRQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_MIPS) |
| if ((interrupt_request & CPU_INTERRUPT_HARD) && |
| cpu_mips_hw_interrupts_pending(env)) { |
| /* Raise it */ |
| env->exception_index = EXCP_EXT_INTERRUPT; |
| env->error_code = 0; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_OPENRISC) |
| { |
| int idx = -1; |
| if ((interrupt_request & CPU_INTERRUPT_HARD) |
| && (env->sr & SR_IEE)) { |
| idx = EXCP_INT; |
| } |
| if ((interrupt_request & CPU_INTERRUPT_TIMER) |
| && (env->sr & SR_TEE)) { |
| idx = EXCP_TICK; |
| } |
| if (idx >= 0) { |
| env->exception_index = idx; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| } |
| #elif defined(TARGET_SPARC) |
| if (interrupt_request & CPU_INTERRUPT_HARD) { |
| if (cpu_interrupts_enabled(env) && |
| env->interrupt_index > 0) { |
| int pil = env->interrupt_index & 0xf; |
| int type = env->interrupt_index & 0xf0; |
| |
| if (((type == TT_EXTINT) && |
| cpu_pil_allowed(env, pil)) || |
| type != TT_EXTINT) { |
| env->exception_index = env->interrupt_index; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| } |
| } |
| #elif defined(TARGET_ARM) |
| if (interrupt_request & CPU_INTERRUPT_FIQ |
| && !(env->uncached_cpsr & CPSR_F)) { |
| env->exception_index = EXCP_FIQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| /* ARMv7-M interrupt return works by loading a magic value |
| into the PC. On real hardware the load causes the |
| return to occur. The qemu implementation performs the |
| jump normally, then does the exception return when the |
| CPU tries to execute code at the magic address. |
| This will cause the magic PC value to be pushed to |
| the stack if an interrupt occurred at the wrong time. |
| We avoid this by disabling interrupts when |
| pc contains a magic address. */ |
| if (interrupt_request & CPU_INTERRUPT_HARD |
| && ((IS_M(env) && env->regs[15] < 0xfffffff0) |
| || !(env->uncached_cpsr & CPSR_I))) { |
| env->exception_index = EXCP_IRQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_UNICORE32) |
| if (interrupt_request & CPU_INTERRUPT_HARD |
| && !(env->uncached_asr & ASR_I)) { |
| env->exception_index = UC32_EXCP_INTR; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_SH4) |
| if (interrupt_request & CPU_INTERRUPT_HARD) { |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_ALPHA) |
| { |
| int idx = -1; |
| /* ??? This hard-codes the OSF/1 interrupt levels. */ |
| switch (env->pal_mode ? 7 : env->ps & PS_INT_MASK) { |
| case 0 ... 3: |
| if (interrupt_request & CPU_INTERRUPT_HARD) { |
| idx = EXCP_DEV_INTERRUPT; |
| } |
| /* FALLTHRU */ |
| case 4: |
| if (interrupt_request & CPU_INTERRUPT_TIMER) { |
| idx = EXCP_CLK_INTERRUPT; |
| } |
| /* FALLTHRU */ |
| case 5: |
| if (interrupt_request & CPU_INTERRUPT_SMP) { |
| idx = EXCP_SMP_INTERRUPT; |
| } |
| /* FALLTHRU */ |
| case 6: |
| if (interrupt_request & CPU_INTERRUPT_MCHK) { |
| idx = EXCP_MCHK; |
| } |
| } |
| if (idx >= 0) { |
| env->exception_index = idx; |
| env->error_code = 0; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| } |
| #elif defined(TARGET_CRIS) |
| if (interrupt_request & CPU_INTERRUPT_HARD |
| && (env->pregs[PR_CCS] & I_FLAG) |
| && !env->locked_irq) { |
| env->exception_index = EXCP_IRQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| if (interrupt_request & CPU_INTERRUPT_NMI) { |
| unsigned int m_flag_archval; |
| if (env->pregs[PR_VR] < 32) { |
| m_flag_archval = M_FLAG_V10; |
| } else { |
| m_flag_archval = M_FLAG_V32; |
| } |
| if ((env->pregs[PR_CCS] & m_flag_archval)) { |
| env->exception_index = EXCP_NMI; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| } |
| #elif defined(TARGET_M68K) |
| if (interrupt_request & CPU_INTERRUPT_HARD |
| && ((env->sr & SR_I) >> SR_I_SHIFT) |
| < env->pending_level) { |
| /* Real hardware gets the interrupt vector via an |
| IACK cycle at this point. Current emulated |
| hardware doesn't rely on this, so we |
| provide/save the vector when the interrupt is |
| first signalled. */ |
| env->exception_index = env->pending_vector; |
| do_interrupt_m68k_hardirq(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_S390X) && !defined(CONFIG_USER_ONLY) |
| if ((interrupt_request & CPU_INTERRUPT_HARD) && |
| (env->psw.mask & PSW_MASK_EXT)) { |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #elif defined(TARGET_XTENSA) |
| if (interrupt_request & CPU_INTERRUPT_HARD) { |
| env->exception_index = EXC_IRQ; |
| do_interrupt(env); |
| next_tb = 0; |
| } |
| #endif |
| /* Don't use the cached interrupt_request value, |
| do_interrupt may have updated the EXITTB flag. */ |
| if (env->interrupt_request & CPU_INTERRUPT_EXITTB) { |
| env->interrupt_request &= ~CPU_INTERRUPT_EXITTB; |
| /* ensure that no TB jump will be modified as |
| the program flow was changed */ |
| next_tb = 0; |
| } |
| } |
| if (unlikely(cpu->exit_request)) { |
| cpu->exit_request = 0; |
| env->exception_index = EXCP_INTERRUPT; |
| cpu_loop_exit(env); |
| } |
| #if defined(DEBUG_DISAS) || defined(CONFIG_DEBUG_EXEC) |
| if (qemu_loglevel_mask(CPU_LOG_TB_CPU)) { |
| /* restore flags in standard format */ |
| #if defined(TARGET_I386) |
| env->eflags = env->eflags | cpu_cc_compute_all(env, CC_OP) |
| | (DF & DF_MASK); |
| log_cpu_state(env, CPU_DUMP_CCOP); |
| env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C); |
| #elif defined(TARGET_M68K) |
| cpu_m68k_flush_flags(env, env->cc_op); |
| env->cc_op = CC_OP_FLAGS; |
| env->sr = (env->sr & 0xffe0) |
| | env->cc_dest | (env->cc_x << 4); |
| log_cpu_state(env, 0); |
| #else |
| log_cpu_state(env, 0); |
| #endif |
| } |
| #endif /* DEBUG_DISAS || CONFIG_DEBUG_EXEC */ |
| spin_lock(&tcg_ctx.tb_ctx.tb_lock); |
| tb = tb_find_fast(env); |
| /* Note: we do it here to avoid a gcc bug on Mac OS X when |
| doing it in tb_find_slow */ |
| if (tcg_ctx.tb_ctx.tb_invalidated_flag) { |
| /* as some TB could have been invalidated because |
| of memory exceptions while generating the code, we |
| must recompute the hash index here */ |
| next_tb = 0; |
| tcg_ctx.tb_ctx.tb_invalidated_flag = 0; |
| } |
| #ifdef CONFIG_DEBUG_EXEC |
| qemu_log_mask(CPU_LOG_EXEC, "Trace %p [" TARGET_FMT_lx "] %s\n", |
| tb->tc_ptr, tb->pc, |
| lookup_symbol(tb->pc)); |
| #endif |
| /* see if we can patch the calling TB. When the TB |
| spans two pages, we cannot safely do a direct |
| jump. */ |
| if (next_tb != 0 && tb->page_addr[1] == -1) { |
| tb_add_jump((TranslationBlock *)(next_tb & ~TB_EXIT_MASK), |
| next_tb & TB_EXIT_MASK, tb); |
| } |
| spin_unlock(&tcg_ctx.tb_ctx.tb_lock); |
| |
| /* cpu_interrupt might be called while translating the |
| TB, but before it is linked into a potentially |
| infinite loop and becomes env->current_tb. Avoid |
| starting execution if there is a pending interrupt. */ |
| cpu->current_tb = tb; |
| barrier(); |
| if (likely(!cpu->exit_request)) { |
| tc_ptr = tb->tc_ptr; |
| /* execute the generated code */ |
| next_tb = cpu_tb_exec(cpu, tc_ptr); |
| switch (next_tb & TB_EXIT_MASK) { |
| case TB_EXIT_REQUESTED: |
| /* Something asked us to stop executing |
| * chained TBs; just continue round the main |
| * loop. Whatever requested the exit will also |
| * have set something else (eg exit_request or |
| * interrupt_request) which we will handle |
| * next time around the loop. |
| */ |
| tb = (TranslationBlock *)(next_tb & ~TB_EXIT_MASK); |
| next_tb = 0; |
| break; |
| case TB_EXIT_ICOUNT_EXPIRED: |
| { |
| /* Instruction counter expired. */ |
| int insns_left; |
| tb = (TranslationBlock *)(next_tb & ~TB_EXIT_MASK); |
| insns_left = env->icount_decr.u32; |
| if (env->icount_extra && insns_left >= 0) { |
| /* Refill decrementer and continue execution. */ |
| env->icount_extra += insns_left; |
| if (env->icount_extra > 0xffff) { |
| insns_left = 0xffff; |
| } else { |
| insns_left = env->icount_extra; |
| } |
| env->icount_extra -= insns_left; |
| env->icount_decr.u16.low = insns_left; |
| } else { |
| if (insns_left > 0) { |
| /* Execute remaining instructions. */ |
| cpu_exec_nocache(env, insns_left, tb); |
| } |
| env->exception_index = EXCP_INTERRUPT; |
| next_tb = 0; |
| cpu_loop_exit(env); |
| } |
| break; |
| } |
| default: |
| break; |
| } |
| } |
| cpu->current_tb = NULL; |
| /* reset soft MMU for next block (it can currently |
| only be set by a memory fault) */ |
| } /* for(;;) */ |
| } else { |
| /* Reload env after longjmp - the compiler may have smashed all |
| * local variables as longjmp is marked 'noreturn'. */ |
| env = cpu_single_env; |
| } |
| } /* for(;;) */ |
| |
| |
| #if defined(TARGET_I386) |
| /* restore flags in standard format */ |
| env->eflags = env->eflags | cpu_cc_compute_all(env, CC_OP) |
| | (DF & DF_MASK); |
| #elif defined(TARGET_ARM) |
| /* XXX: Save/restore host fpu exception state?. */ |
| #elif defined(TARGET_UNICORE32) |
| #elif defined(TARGET_SPARC) |
| #elif defined(TARGET_PPC) |
| #elif defined(TARGET_LM32) |
| #elif defined(TARGET_M68K) |
| cpu_m68k_flush_flags(env, env->cc_op); |
| env->cc_op = CC_OP_FLAGS; |
| env->sr = (env->sr & 0xffe0) |
| | env->cc_dest | (env->cc_x << 4); |
| #elif defined(TARGET_MICROBLAZE) |
| #elif defined(TARGET_MIPS) |
| #elif defined(TARGET_OPENRISC) |
| #elif defined(TARGET_SH4) |
| #elif defined(TARGET_ALPHA) |
| #elif defined(TARGET_CRIS) |
| #elif defined(TARGET_S390X) |
| #elif defined(TARGET_XTENSA) |
| /* XXXXX */ |
| #else |
| #error unsupported target CPU |
| #endif |
| |
| /* fail safe : never use cpu_single_env outside cpu_exec() */ |
| cpu_single_env = NULL; |
| return ret; |
| } |
