| /* | 
 |  *  ARM helper routines | 
 |  * | 
 |  *  Copyright (c) 2005-2007 CodeSourcery, LLC | 
 |  * | 
 |  * 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 "cpu.h" | 
 | #include "exec/helper-proto.h" | 
 | #include "internals.h" | 
 | #include "exec/cpu_ldst.h" | 
 |  | 
 | #define SIGNBIT (uint32_t)0x80000000 | 
 | #define SIGNBIT64 ((uint64_t)1 << 63) | 
 |  | 
 | static void raise_exception(CPUARMState *env, int tt) | 
 | { | 
 |     ARMCPU *cpu = arm_env_get_cpu(env); | 
 |     CPUState *cs = CPU(cpu); | 
 |  | 
 |     cs->exception_index = tt; | 
 |     cpu_loop_exit(cs); | 
 | } | 
 |  | 
 | uint32_t HELPER(neon_tbl)(CPUARMState *env, uint32_t ireg, uint32_t def, | 
 |                           uint32_t rn, uint32_t maxindex) | 
 | { | 
 |     uint32_t val; | 
 |     uint32_t tmp; | 
 |     int index; | 
 |     int shift; | 
 |     uint64_t *table; | 
 |     table = (uint64_t *)&env->vfp.regs[rn]; | 
 |     val = 0; | 
 |     for (shift = 0; shift < 32; shift += 8) { | 
 |         index = (ireg >> shift) & 0xff; | 
 |         if (index < maxindex) { | 
 |             tmp = (table[index >> 3] >> ((index & 7) << 3)) & 0xff; | 
 |             val |= tmp << shift; | 
 |         } else { | 
 |             val |= def & (0xff << shift); | 
 |         } | 
 |     } | 
 |     return val; | 
 | } | 
 |  | 
 | #if !defined(CONFIG_USER_ONLY) | 
 |  | 
 | /* try to fill the TLB and return an exception if error. If retaddr is | 
 |  * NULL, it means that the function was called in C code (i.e. not | 
 |  * from generated code or from helper.c) | 
 |  */ | 
 | void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx, | 
 |               uintptr_t retaddr) | 
 | { | 
 |     int ret; | 
 |  | 
 |     ret = arm_cpu_handle_mmu_fault(cs, addr, is_write, mmu_idx); | 
 |     if (unlikely(ret)) { | 
 |         ARMCPU *cpu = ARM_CPU(cs); | 
 |         CPUARMState *env = &cpu->env; | 
 |  | 
 |         if (retaddr) { | 
 |             /* now we have a real cpu fault */ | 
 |             cpu_restore_state(cs, retaddr); | 
 |         } | 
 |         raise_exception(env, cs->exception_index); | 
 |     } | 
 | } | 
 | #endif | 
 |  | 
 | uint32_t HELPER(add_setq)(CPUARMState *env, uint32_t a, uint32_t b) | 
 | { | 
 |     uint32_t res = a + b; | 
 |     if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT)) | 
 |         env->QF = 1; | 
 |     return res; | 
 | } | 
 |  | 
 | uint32_t HELPER(add_saturate)(CPUARMState *env, uint32_t a, uint32_t b) | 
 | { | 
 |     uint32_t res = a + b; | 
 |     if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT)) { | 
 |         env->QF = 1; | 
 |         res = ~(((int32_t)a >> 31) ^ SIGNBIT); | 
 |     } | 
 |     return res; | 
 | } | 
 |  | 
 | uint32_t HELPER(sub_saturate)(CPUARMState *env, uint32_t a, uint32_t b) | 
 | { | 
 |     uint32_t res = a - b; | 
 |     if (((res ^ a) & SIGNBIT) && ((a ^ b) & SIGNBIT)) { | 
 |         env->QF = 1; | 
 |         res = ~(((int32_t)a >> 31) ^ SIGNBIT); | 
 |     } | 
 |     return res; | 
 | } | 
 |  | 
 | uint32_t HELPER(double_saturate)(CPUARMState *env, int32_t val) | 
 | { | 
 |     uint32_t res; | 
 |     if (val >= 0x40000000) { | 
 |         res = ~SIGNBIT; | 
 |         env->QF = 1; | 
 |     } else if (val <= (int32_t)0xc0000000) { | 
 |         res = SIGNBIT; | 
 |         env->QF = 1; | 
 |     } else { | 
 |         res = val << 1; | 
 |     } | 
 |     return res; | 
 | } | 
 |  | 
 | uint32_t HELPER(add_usaturate)(CPUARMState *env, uint32_t a, uint32_t b) | 
 | { | 
 |     uint32_t res = a + b; | 
 |     if (res < a) { | 
 |         env->QF = 1; | 
 |         res = ~0; | 
 |     } | 
 |     return res; | 
 | } | 
 |  | 
 | uint32_t HELPER(sub_usaturate)(CPUARMState *env, uint32_t a, uint32_t b) | 
 | { | 
 |     uint32_t res = a - b; | 
 |     if (res > a) { | 
 |         env->QF = 1; | 
 |         res = 0; | 
 |     } | 
 |     return res; | 
 | } | 
 |  | 
 | /* Signed saturation.  */ | 
 | static inline uint32_t do_ssat(CPUARMState *env, int32_t val, int shift) | 
 | { | 
 |     int32_t top; | 
 |     uint32_t mask; | 
 |  | 
 |     top = val >> shift; | 
 |     mask = (1u << shift) - 1; | 
 |     if (top > 0) { | 
 |         env->QF = 1; | 
 |         return mask; | 
 |     } else if (top < -1) { | 
 |         env->QF = 1; | 
 |         return ~mask; | 
 |     } | 
 |     return val; | 
 | } | 
 |  | 
 | /* Unsigned saturation.  */ | 
 | static inline uint32_t do_usat(CPUARMState *env, int32_t val, int shift) | 
 | { | 
 |     uint32_t max; | 
 |  | 
 |     max = (1u << shift) - 1; | 
 |     if (val < 0) { | 
 |         env->QF = 1; | 
 |         return 0; | 
 |     } else if (val > max) { | 
 |         env->QF = 1; | 
 |         return max; | 
 |     } | 
 |     return val; | 
 | } | 
 |  | 
 | /* Signed saturate.  */ | 
 | uint32_t HELPER(ssat)(CPUARMState *env, uint32_t x, uint32_t shift) | 
 | { | 
 |     return do_ssat(env, x, shift); | 
 | } | 
 |  | 
 | /* Dual halfword signed saturate.  */ | 
 | uint32_t HELPER(ssat16)(CPUARMState *env, uint32_t x, uint32_t shift) | 
 | { | 
 |     uint32_t res; | 
 |  | 
 |     res = (uint16_t)do_ssat(env, (int16_t)x, shift); | 
 |     res |= do_ssat(env, ((int32_t)x) >> 16, shift) << 16; | 
 |     return res; | 
 | } | 
 |  | 
 | /* Unsigned saturate.  */ | 
 | uint32_t HELPER(usat)(CPUARMState *env, uint32_t x, uint32_t shift) | 
 | { | 
 |     return do_usat(env, x, shift); | 
 | } | 
 |  | 
 | /* Dual halfword unsigned saturate.  */ | 
 | uint32_t HELPER(usat16)(CPUARMState *env, uint32_t x, uint32_t shift) | 
 | { | 
 |     uint32_t res; | 
 |  | 
 |     res = (uint16_t)do_usat(env, (int16_t)x, shift); | 
 |     res |= do_usat(env, ((int32_t)x) >> 16, shift) << 16; | 
 |     return res; | 
 | } | 
 |  | 
 | void HELPER(wfi)(CPUARMState *env) | 
 | { | 
 |     CPUState *cs = CPU(arm_env_get_cpu(env)); | 
 |  | 
 |     cs->exception_index = EXCP_HLT; | 
 |     cs->halted = 1; | 
 |     cpu_loop_exit(cs); | 
 | } | 
 |  | 
 | void HELPER(wfe)(CPUARMState *env) | 
 | { | 
 |     CPUState *cs = CPU(arm_env_get_cpu(env)); | 
 |  | 
 |     /* Don't actually halt the CPU, just yield back to top | 
 |      * level loop | 
 |      */ | 
 |     cs->exception_index = EXCP_YIELD; | 
 |     cpu_loop_exit(cs); | 
 | } | 
 |  | 
 | /* Raise an internal-to-QEMU exception. This is limited to only | 
 |  * those EXCP values which are special cases for QEMU to interrupt | 
 |  * execution and not to be used for exceptions which are passed to | 
 |  * the guest (those must all have syndrome information and thus should | 
 |  * use exception_with_syndrome). | 
 |  */ | 
 | void HELPER(exception_internal)(CPUARMState *env, uint32_t excp) | 
 | { | 
 |     CPUState *cs = CPU(arm_env_get_cpu(env)); | 
 |  | 
 |     assert(excp_is_internal(excp)); | 
 |     cs->exception_index = excp; | 
 |     cpu_loop_exit(cs); | 
 | } | 
 |  | 
 | /* Raise an exception with the specified syndrome register value */ | 
 | void HELPER(exception_with_syndrome)(CPUARMState *env, uint32_t excp, | 
 |                                      uint32_t syndrome) | 
 | { | 
 |     CPUState *cs = CPU(arm_env_get_cpu(env)); | 
 |  | 
 |     assert(!excp_is_internal(excp)); | 
 |     cs->exception_index = excp; | 
 |     env->exception.syndrome = syndrome; | 
 |     cpu_loop_exit(cs); | 
 | } | 
 |  | 
 | uint32_t HELPER(cpsr_read)(CPUARMState *env) | 
 | { | 
 |     return cpsr_read(env) & ~(CPSR_EXEC | CPSR_RESERVED); | 
 | } | 
 |  | 
 | void HELPER(cpsr_write)(CPUARMState *env, uint32_t val, uint32_t mask) | 
 | { | 
 |     cpsr_write(env, val, mask); | 
 | } | 
 |  | 
 | /* Access to user mode registers from privileged modes.  */ | 
 | uint32_t HELPER(get_user_reg)(CPUARMState *env, uint32_t regno) | 
 | { | 
 |     uint32_t val; | 
 |  | 
 |     if (regno == 13) { | 
 |         val = env->banked_r13[0]; | 
 |     } else if (regno == 14) { | 
 |         val = env->banked_r14[0]; | 
 |     } else if (regno >= 8 | 
 |                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) { | 
 |         val = env->usr_regs[regno - 8]; | 
 |     } else { | 
 |         val = env->regs[regno]; | 
 |     } | 
 |     return val; | 
 | } | 
 |  | 
 | void HELPER(set_user_reg)(CPUARMState *env, uint32_t regno, uint32_t val) | 
 | { | 
 |     if (regno == 13) { | 
 |         env->banked_r13[0] = val; | 
 |     } else if (regno == 14) { | 
 |         env->banked_r14[0] = val; | 
 |     } else if (regno >= 8 | 
 |                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) { | 
 |         env->usr_regs[regno - 8] = val; | 
 |     } else { | 
 |         env->regs[regno] = val; | 
 |     } | 
 | } | 
 |  | 
 | void HELPER(access_check_cp_reg)(CPUARMState *env, void *rip, uint32_t syndrome) | 
 | { | 
 |     const ARMCPRegInfo *ri = rip; | 
 |  | 
 |     if (arm_feature(env, ARM_FEATURE_XSCALE) && ri->cp < 14 | 
 |         && extract32(env->cp15.c15_cpar, ri->cp, 1) == 0) { | 
 |         env->exception.syndrome = syndrome; | 
 |         raise_exception(env, EXCP_UDEF); | 
 |     } | 
 |  | 
 |     if (!ri->accessfn) { | 
 |         return; | 
 |     } | 
 |  | 
 |     switch (ri->accessfn(env, ri)) { | 
 |     case CP_ACCESS_OK: | 
 |         return; | 
 |     case CP_ACCESS_TRAP: | 
 |         env->exception.syndrome = syndrome; | 
 |         break; | 
 |     case CP_ACCESS_TRAP_UNCATEGORIZED: | 
 |         env->exception.syndrome = syn_uncategorized(); | 
 |         break; | 
 |     default: | 
 |         g_assert_not_reached(); | 
 |     } | 
 |     raise_exception(env, EXCP_UDEF); | 
 | } | 
 |  | 
 | void HELPER(set_cp_reg)(CPUARMState *env, void *rip, uint32_t value) | 
 | { | 
 |     const ARMCPRegInfo *ri = rip; | 
 |  | 
 |     ri->writefn(env, ri, value); | 
 | } | 
 |  | 
 | uint32_t HELPER(get_cp_reg)(CPUARMState *env, void *rip) | 
 | { | 
 |     const ARMCPRegInfo *ri = rip; | 
 |  | 
 |     return ri->readfn(env, ri); | 
 | } | 
 |  | 
 | void HELPER(set_cp_reg64)(CPUARMState *env, void *rip, uint64_t value) | 
 | { | 
 |     const ARMCPRegInfo *ri = rip; | 
 |  | 
 |     ri->writefn(env, ri, value); | 
 | } | 
 |  | 
 | uint64_t HELPER(get_cp_reg64)(CPUARMState *env, void *rip) | 
 | { | 
 |     const ARMCPRegInfo *ri = rip; | 
 |  | 
 |     return ri->readfn(env, ri); | 
 | } | 
 |  | 
 | void HELPER(msr_i_pstate)(CPUARMState *env, uint32_t op, uint32_t imm) | 
 | { | 
 |     /* MSR_i to update PSTATE. This is OK from EL0 only if UMA is set. | 
 |      * Note that SPSel is never OK from EL0; we rely on handle_msr_i() | 
 |      * to catch that case at translate time. | 
 |      */ | 
 |     if (arm_current_pl(env) == 0 && !(env->cp15.c1_sys & SCTLR_UMA)) { | 
 |         raise_exception(env, EXCP_UDEF); | 
 |     } | 
 |  | 
 |     switch (op) { | 
 |     case 0x05: /* SPSel */ | 
 |         update_spsel(env, imm); | 
 |         break; | 
 |     case 0x1e: /* DAIFSet */ | 
 |         env->daif |= (imm << 6) & PSTATE_DAIF; | 
 |         break; | 
 |     case 0x1f: /* DAIFClear */ | 
 |         env->daif &= ~((imm << 6) & PSTATE_DAIF); | 
 |         break; | 
 |     default: | 
 |         g_assert_not_reached(); | 
 |     } | 
 | } | 
 |  | 
 | void HELPER(clear_pstate_ss)(CPUARMState *env) | 
 | { | 
 |     env->pstate &= ~PSTATE_SS; | 
 | } | 
 |  | 
 | void HELPER(pre_hvc)(CPUARMState *env) | 
 | { | 
 |     int cur_el = arm_current_pl(env); | 
 |     /* FIXME: Use actual secure state.  */ | 
 |     bool secure = false; | 
 |     bool undef; | 
 |  | 
 |     /* We've already checked that EL2 exists at translation time. | 
 |      * EL3.HCE has priority over EL2.HCD. | 
 |      */ | 
 |     if (arm_feature(env, ARM_FEATURE_EL3)) { | 
 |         undef = !(env->cp15.scr_el3 & SCR_HCE); | 
 |     } else { | 
 |         undef = env->cp15.hcr_el2 & HCR_HCD; | 
 |     } | 
 |  | 
 |     /* In ARMv7 and ARMv8/AArch32, HVC is undef in secure state. | 
 |      * For ARMv8/AArch64, HVC is allowed in EL3. | 
 |      * Note that we've already trapped HVC from EL0 at translation | 
 |      * time. | 
 |      */ | 
 |     if (secure && (!is_a64(env) || cur_el == 1)) { | 
 |         undef = true; | 
 |     } | 
 |  | 
 |     if (undef) { | 
 |         env->exception.syndrome = syn_uncategorized(); | 
 |         raise_exception(env, EXCP_UDEF); | 
 |     } | 
 | } | 
 |  | 
 | void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome) | 
 | { | 
 |     int cur_el = arm_current_pl(env); | 
 |     /* FIXME: Use real secure state.  */ | 
 |     bool secure = false; | 
 |     bool smd = env->cp15.scr_el3 & SCR_SMD; | 
 |     /* On ARMv8 AArch32, SMD only applies to NS state. | 
 |      * On ARMv7 SMD only applies to NS state and only if EL2 is available. | 
 |      * For ARMv7 non EL2, we force SMD to zero so we don't need to re-check | 
 |      * the EL2 condition here. | 
 |      */ | 
 |     bool undef = is_a64(env) ? smd : (!secure && smd); | 
 |  | 
 |     /* In NS EL1, HCR controlled routing to EL2 has priority over SMD.  */ | 
 |     if (!secure && cur_el == 1 && (env->cp15.hcr_el2 & HCR_TSC)) { | 
 |         env->exception.syndrome = syndrome; | 
 |         raise_exception(env, EXCP_HYP_TRAP); | 
 |     } | 
 |  | 
 |     /* We've already checked that EL3 exists at translation time.  */ | 
 |     if (undef) { | 
 |         env->exception.syndrome = syn_uncategorized(); | 
 |         raise_exception(env, EXCP_UDEF); | 
 |     } | 
 | } | 
 |  | 
 | void HELPER(exception_return)(CPUARMState *env) | 
 | { | 
 |     int cur_el = arm_current_pl(env); | 
 |     unsigned int spsr_idx = aarch64_banked_spsr_index(cur_el); | 
 |     uint32_t spsr = env->banked_spsr[spsr_idx]; | 
 |     int new_el, i; | 
 |  | 
 |     aarch64_save_sp(env, cur_el); | 
 |  | 
 |     env->exclusive_addr = -1; | 
 |  | 
 |     /* We must squash the PSTATE.SS bit to zero unless both of the | 
 |      * following hold: | 
 |      *  1. debug exceptions are currently disabled | 
 |      *  2. singlestep will be active in the EL we return to | 
 |      * We check 1 here and 2 after we've done the pstate/cpsr write() to | 
 |      * transition to the EL we're going to. | 
 |      */ | 
 |     if (arm_generate_debug_exceptions(env)) { | 
 |         spsr &= ~PSTATE_SS; | 
 |     } | 
 |  | 
 |     if (spsr & PSTATE_nRW) { | 
 |         /* TODO: We currently assume EL1/2/3 are running in AArch64.  */ | 
 |         env->aarch64 = 0; | 
 |         new_el = 0; | 
 |         env->uncached_cpsr = 0x10; | 
 |         cpsr_write(env, spsr, ~0); | 
 |         if (!arm_singlestep_active(env)) { | 
 |             env->uncached_cpsr &= ~PSTATE_SS; | 
 |         } | 
 |         for (i = 0; i < 15; i++) { | 
 |             env->regs[i] = env->xregs[i]; | 
 |         } | 
 |  | 
 |         env->regs[15] = env->elr_el[1] & ~0x1; | 
 |     } else { | 
 |         new_el = extract32(spsr, 2, 2); | 
 |         if (new_el > cur_el | 
 |             || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) { | 
 |             /* Disallow return to an EL which is unimplemented or higher | 
 |              * than the current one. | 
 |              */ | 
 |             goto illegal_return; | 
 |         } | 
 |         if (extract32(spsr, 1, 1)) { | 
 |             /* Return with reserved M[1] bit set */ | 
 |             goto illegal_return; | 
 |         } | 
 |         if (new_el == 0 && (spsr & PSTATE_SP)) { | 
 |             /* Return to EL0 with M[0] bit set */ | 
 |             goto illegal_return; | 
 |         } | 
 |         env->aarch64 = 1; | 
 |         pstate_write(env, spsr); | 
 |         if (!arm_singlestep_active(env)) { | 
 |             env->pstate &= ~PSTATE_SS; | 
 |         } | 
 |         aarch64_restore_sp(env, new_el); | 
 |         env->pc = env->elr_el[cur_el]; | 
 |     } | 
 |  | 
 |     return; | 
 |  | 
 | illegal_return: | 
 |     /* Illegal return events of various kinds have architecturally | 
 |      * mandated behaviour: | 
 |      * restore NZCV and DAIF from SPSR_ELx | 
 |      * set PSTATE.IL | 
 |      * restore PC from ELR_ELx | 
 |      * no change to exception level, execution state or stack pointer | 
 |      */ | 
 |     env->pstate |= PSTATE_IL; | 
 |     env->pc = env->elr_el[cur_el]; | 
 |     spsr &= PSTATE_NZCV | PSTATE_DAIF; | 
 |     spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF); | 
 |     pstate_write(env, spsr); | 
 |     if (!arm_singlestep_active(env)) { | 
 |         env->pstate &= ~PSTATE_SS; | 
 |     } | 
 | } | 
 |  | 
 | /* Return true if the linked breakpoint entry lbn passes its checks */ | 
 | static bool linked_bp_matches(ARMCPU *cpu, int lbn) | 
 | { | 
 |     CPUARMState *env = &cpu->env; | 
 |     uint64_t bcr = env->cp15.dbgbcr[lbn]; | 
 |     int brps = extract32(cpu->dbgdidr, 24, 4); | 
 |     int ctx_cmps = extract32(cpu->dbgdidr, 20, 4); | 
 |     int bt; | 
 |     uint32_t contextidr; | 
 |  | 
 |     /* Links to unimplemented or non-context aware breakpoints are | 
 |      * CONSTRAINED UNPREDICTABLE: either behave as if disabled, or | 
 |      * as if linked to an UNKNOWN context-aware breakpoint (in which | 
 |      * case DBGWCR<n>_EL1.LBN must indicate that breakpoint). | 
 |      * We choose the former. | 
 |      */ | 
 |     if (lbn > brps || lbn < (brps - ctx_cmps)) { | 
 |         return false; | 
 |     } | 
 |  | 
 |     bcr = env->cp15.dbgbcr[lbn]; | 
 |  | 
 |     if (extract64(bcr, 0, 1) == 0) { | 
 |         /* Linked breakpoint disabled : generate no events */ | 
 |         return false; | 
 |     } | 
 |  | 
 |     bt = extract64(bcr, 20, 4); | 
 |  | 
 |     /* We match the whole register even if this is AArch32 using the | 
 |      * short descriptor format (in which case it holds both PROCID and ASID), | 
 |      * since we don't implement the optional v7 context ID masking. | 
 |      */ | 
 |     contextidr = extract64(env->cp15.contextidr_el1, 0, 32); | 
 |  | 
 |     switch (bt) { | 
 |     case 3: /* linked context ID match */ | 
 |         if (arm_current_pl(env) > 1) { | 
 |             /* Context matches never fire in EL2 or (AArch64) EL3 */ | 
 |             return false; | 
 |         } | 
 |         return (contextidr == extract64(env->cp15.dbgbvr[lbn], 0, 32)); | 
 |     case 5: /* linked address mismatch (reserved in AArch64) */ | 
 |     case 9: /* linked VMID match (reserved if no EL2) */ | 
 |     case 11: /* linked context ID and VMID match (reserved if no EL2) */ | 
 |     default: | 
 |         /* Links to Unlinked context breakpoints must generate no | 
 |          * events; we choose to do the same for reserved values too. | 
 |          */ | 
 |         return false; | 
 |     } | 
 |  | 
 |     return false; | 
 | } | 
 |  | 
 | static bool bp_wp_matches(ARMCPU *cpu, int n, bool is_wp) | 
 | { | 
 |     CPUARMState *env = &cpu->env; | 
 |     uint64_t cr; | 
 |     int pac, hmc, ssc, wt, lbn; | 
 |     /* TODO: check against CPU security state when we implement TrustZone */ | 
 |     bool is_secure = false; | 
 |  | 
 |     if (is_wp) { | 
 |         if (!env->cpu_watchpoint[n] | 
 |             || !(env->cpu_watchpoint[n]->flags & BP_WATCHPOINT_HIT)) { | 
 |             return false; | 
 |         } | 
 |         cr = env->cp15.dbgwcr[n]; | 
 |     } else { | 
 |         uint64_t pc = is_a64(env) ? env->pc : env->regs[15]; | 
 |  | 
 |         if (!env->cpu_breakpoint[n] || env->cpu_breakpoint[n]->pc != pc) { | 
 |             return false; | 
 |         } | 
 |         cr = env->cp15.dbgbcr[n]; | 
 |     } | 
 |     /* The WATCHPOINT_HIT flag guarantees us that the watchpoint is | 
 |      * enabled and that the address and access type match; for breakpoints | 
 |      * we know the address matched; check the remaining fields, including | 
 |      * linked breakpoints. We rely on WCR and BCR having the same layout | 
 |      * for the LBN, SSC, HMC, PAC/PMC and is-linked fields. | 
 |      * Note that some combinations of {PAC, HMC, SSC} are reserved and | 
 |      * must act either like some valid combination or as if the watchpoint | 
 |      * were disabled. We choose the former, and use this together with | 
 |      * the fact that EL3 must always be Secure and EL2 must always be | 
 |      * Non-Secure to simplify the code slightly compared to the full | 
 |      * table in the ARM ARM. | 
 |      */ | 
 |     pac = extract64(cr, 1, 2); | 
 |     hmc = extract64(cr, 13, 1); | 
 |     ssc = extract64(cr, 14, 2); | 
 |  | 
 |     switch (ssc) { | 
 |     case 0: | 
 |         break; | 
 |     case 1: | 
 |     case 3: | 
 |         if (is_secure) { | 
 |             return false; | 
 |         } | 
 |         break; | 
 |     case 2: | 
 |         if (!is_secure) { | 
 |             return false; | 
 |         } | 
 |         break; | 
 |     } | 
 |  | 
 |     /* TODO: this is not strictly correct because the LDRT/STRT/LDT/STT | 
 |      * "unprivileged access" instructions should match watchpoints as if | 
 |      * they were accesses done at EL0, even if the CPU is at EL1 or higher. | 
 |      * Implementing this would require reworking the core watchpoint code | 
 |      * to plumb the mmu_idx through to this point. Luckily Linux does not | 
 |      * rely on this behaviour currently. | 
 |      * For breakpoints we do want to use the current CPU state. | 
 |      */ | 
 |     switch (arm_current_pl(env)) { | 
 |     case 3: | 
 |     case 2: | 
 |         if (!hmc) { | 
 |             return false; | 
 |         } | 
 |         break; | 
 |     case 1: | 
 |         if (extract32(pac, 0, 1) == 0) { | 
 |             return false; | 
 |         } | 
 |         break; | 
 |     case 0: | 
 |         if (extract32(pac, 1, 1) == 0) { | 
 |             return false; | 
 |         } | 
 |         break; | 
 |     default: | 
 |         g_assert_not_reached(); | 
 |     } | 
 |  | 
 |     wt = extract64(cr, 20, 1); | 
 |     lbn = extract64(cr, 16, 4); | 
 |  | 
 |     if (wt && !linked_bp_matches(cpu, lbn)) { | 
 |         return false; | 
 |     } | 
 |  | 
 |     return true; | 
 | } | 
 |  | 
 | static bool check_watchpoints(ARMCPU *cpu) | 
 | { | 
 |     CPUARMState *env = &cpu->env; | 
 |     int n; | 
 |  | 
 |     /* If watchpoints are disabled globally or we can't take debug | 
 |      * exceptions here then watchpoint firings are ignored. | 
 |      */ | 
 |     if (extract32(env->cp15.mdscr_el1, 15, 1) == 0 | 
 |         || !arm_generate_debug_exceptions(env)) { | 
 |         return false; | 
 |     } | 
 |  | 
 |     for (n = 0; n < ARRAY_SIZE(env->cpu_watchpoint); n++) { | 
 |         if (bp_wp_matches(cpu, n, true)) { | 
 |             return true; | 
 |         } | 
 |     } | 
 |     return false; | 
 | } | 
 |  | 
 | static bool check_breakpoints(ARMCPU *cpu) | 
 | { | 
 |     CPUARMState *env = &cpu->env; | 
 |     int n; | 
 |  | 
 |     /* If breakpoints are disabled globally or we can't take debug | 
 |      * exceptions here then breakpoint firings are ignored. | 
 |      */ | 
 |     if (extract32(env->cp15.mdscr_el1, 15, 1) == 0 | 
 |         || !arm_generate_debug_exceptions(env)) { | 
 |         return false; | 
 |     } | 
 |  | 
 |     for (n = 0; n < ARRAY_SIZE(env->cpu_breakpoint); n++) { | 
 |         if (bp_wp_matches(cpu, n, false)) { | 
 |             return true; | 
 |         } | 
 |     } | 
 |     return false; | 
 | } | 
 |  | 
 | void arm_debug_excp_handler(CPUState *cs) | 
 | { | 
 |     /* Called by core code when a watchpoint or breakpoint fires; | 
 |      * need to check which one and raise the appropriate exception. | 
 |      */ | 
 |     ARMCPU *cpu = ARM_CPU(cs); | 
 |     CPUARMState *env = &cpu->env; | 
 |     CPUWatchpoint *wp_hit = cs->watchpoint_hit; | 
 |  | 
 |     if (wp_hit) { | 
 |         if (wp_hit->flags & BP_CPU) { | 
 |             cs->watchpoint_hit = NULL; | 
 |             if (check_watchpoints(cpu)) { | 
 |                 bool wnr = (wp_hit->flags & BP_WATCHPOINT_HIT_WRITE) != 0; | 
 |                 bool same_el = arm_debug_target_el(env) == arm_current_pl(env); | 
 |  | 
 |                 env->exception.syndrome = syn_watchpoint(same_el, 0, wnr); | 
 |                 if (extended_addresses_enabled(env)) { | 
 |                     env->exception.fsr = (1 << 9) | 0x22; | 
 |                 } else { | 
 |                     env->exception.fsr = 0x2; | 
 |                 } | 
 |                 env->exception.vaddress = wp_hit->hitaddr; | 
 |                 raise_exception(env, EXCP_DATA_ABORT); | 
 |             } else { | 
 |                 cpu_resume_from_signal(cs, NULL); | 
 |             } | 
 |         } | 
 |     } else { | 
 |         if (check_breakpoints(cpu)) { | 
 |             bool same_el = (arm_debug_target_el(env) == arm_current_pl(env)); | 
 |             env->exception.syndrome = syn_breakpoint(same_el); | 
 |             if (extended_addresses_enabled(env)) { | 
 |                 env->exception.fsr = (1 << 9) | 0x22; | 
 |             } else { | 
 |                 env->exception.fsr = 0x2; | 
 |             } | 
 |             /* FAR is UNKNOWN, so doesn't need setting */ | 
 |             raise_exception(env, EXCP_PREFETCH_ABORT); | 
 |         } | 
 |     } | 
 | } | 
 |  | 
 | /* ??? Flag setting arithmetic is awkward because we need to do comparisons. | 
 |    The only way to do that in TCG is a conditional branch, which clobbers | 
 |    all our temporaries.  For now implement these as helper functions.  */ | 
 |  | 
 | /* Similarly for variable shift instructions.  */ | 
 |  | 
 | uint32_t HELPER(shl_cc)(CPUARMState *env, uint32_t x, uint32_t i) | 
 | { | 
 |     int shift = i & 0xff; | 
 |     if (shift >= 32) { | 
 |         if (shift == 32) | 
 |             env->CF = x & 1; | 
 |         else | 
 |             env->CF = 0; | 
 |         return 0; | 
 |     } else if (shift != 0) { | 
 |         env->CF = (x >> (32 - shift)) & 1; | 
 |         return x << shift; | 
 |     } | 
 |     return x; | 
 | } | 
 |  | 
 | uint32_t HELPER(shr_cc)(CPUARMState *env, uint32_t x, uint32_t i) | 
 | { | 
 |     int shift = i & 0xff; | 
 |     if (shift >= 32) { | 
 |         if (shift == 32) | 
 |             env->CF = (x >> 31) & 1; | 
 |         else | 
 |             env->CF = 0; | 
 |         return 0; | 
 |     } else if (shift != 0) { | 
 |         env->CF = (x >> (shift - 1)) & 1; | 
 |         return x >> shift; | 
 |     } | 
 |     return x; | 
 | } | 
 |  | 
 | uint32_t HELPER(sar_cc)(CPUARMState *env, uint32_t x, uint32_t i) | 
 | { | 
 |     int shift = i & 0xff; | 
 |     if (shift >= 32) { | 
 |         env->CF = (x >> 31) & 1; | 
 |         return (int32_t)x >> 31; | 
 |     } else if (shift != 0) { | 
 |         env->CF = (x >> (shift - 1)) & 1; | 
 |         return (int32_t)x >> shift; | 
 |     } | 
 |     return x; | 
 | } | 
 |  | 
 | uint32_t HELPER(ror_cc)(CPUARMState *env, uint32_t x, uint32_t i) | 
 | { | 
 |     int shift1, shift; | 
 |     shift1 = i & 0xff; | 
 |     shift = shift1 & 0x1f; | 
 |     if (shift == 0) { | 
 |         if (shift1 != 0) | 
 |             env->CF = (x >> 31) & 1; | 
 |         return x; | 
 |     } else { | 
 |         env->CF = (x >> (shift - 1)) & 1; | 
 |         return ((uint32_t)x >> shift) | (x << (32 - shift)); | 
 |     } | 
 | } |