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-rw-r--r--target/arm/cpu.c43
-rw-r--r--target/arm/cpu.h10
-rw-r--r--target/arm/helper.c19
-rw-r--r--target/arm/internals.h21
-rw-r--r--target/arm/kvm64.c4
-rw-r--r--target/arm/op_helper.c23
-rw-r--r--target/arm/translate.c181
-rw-r--r--target/arm/translate.h5
8 files changed, 178 insertions, 128 deletions
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 04b062cb7e..b357aee778 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -304,33 +304,6 @@ bool arm_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 }
 
 #if !defined(CONFIG_USER_ONLY) || !defined(TARGET_AARCH64)
-static void arm_v7m_unassigned_access(CPUState *cpu, hwaddr addr,
-                                      bool is_write, bool is_exec, int opaque,
-                                      unsigned size)
-{
-    ARMCPU *arm = ARM_CPU(cpu);
-    CPUARMState *env = &arm->env;
-
-    /* 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 by throwing a special exception when when the CPU tries to
-     * execute code at the magic address.
-     */
-    if (env->v7m.exception != 0 && addr >= 0xfffffff0 && is_exec) {
-        cpu->exception_index = EXCP_EXCEPTION_EXIT;
-        cpu_loop_exit(cpu);
-    }
-
-    /* In real hardware an attempt to access parts of the address space
-     * with nothing there will usually cause an external abort.
-     * However our QEMU board models are often missing device models where
-     * the guest can boot anyway with the default read-as-zero/writes-ignored
-     * behaviour that you get without a QEMU unassigned_access hook.
-     * So just return here to retain that default behaviour.
-     */
-}
-
 static bool arm_v7m_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
 {
     CPUClass *cc = CPU_GET_CLASS(cs);
@@ -338,17 +311,7 @@ static bool arm_v7m_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
     CPUARMState *env = &cpu->env;
     bool ret = false;
 
-    /* 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.
-     *
-     * ARMv7-M interrupt masking works differently than -A or -R.
+    /* ARMv7-M interrupt masking works differently than -A or -R.
      * There is no FIQ/IRQ distinction. Instead of I and F bits
      * masking FIQ and IRQ interrupts, an exception is taken only
      * if it is higher priority than the current execution priority
@@ -356,8 +319,7 @@ static bool arm_v7m_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
      * currently active exception).
      */
     if (interrupt_request & CPU_INTERRUPT_HARD
-        && (armv7m_nvic_can_take_pending_exception(env->nvic))
-        && (env->regs[15] < 0xfffffff0)) {
+        && (armv7m_nvic_can_take_pending_exception(env->nvic))) {
         cs->exception_index = EXCP_IRQ;
         cc->do_interrupt(cs);
         ret = true;
@@ -1091,7 +1053,6 @@ static void arm_v7m_class_init(ObjectClass *oc, void *data)
     cc->do_interrupt = arm_v7m_cpu_do_interrupt;
 #endif
 
-    cc->do_unassigned_access = arm_v7m_unassigned_access;
     cc->cpu_exec_interrupt = arm_v7m_cpu_exec_interrupt;
 }
 
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index a8aabce7dd..1055bfef3d 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -58,6 +58,7 @@
 #define EXCP_SEMIHOST       16   /* semihosting call */
 #define EXCP_NOCP           17   /* v7M NOCP UsageFault */
 #define EXCP_INVSTATE       18   /* v7M INVSTATE UsageFault */
+/* NB: add new EXCP_ defines to the array in arm_log_exception() too */
 
 #define ARMV7M_EXCP_RESET   1
 #define ARMV7M_EXCP_NMI     2
@@ -2290,6 +2291,9 @@ static inline bool arm_cpu_data_is_big_endian(CPUARMState *env)
 #define ARM_TBFLAG_NS_MASK          (1 << ARM_TBFLAG_NS_SHIFT)
 #define ARM_TBFLAG_BE_DATA_SHIFT    20
 #define ARM_TBFLAG_BE_DATA_MASK     (1 << ARM_TBFLAG_BE_DATA_SHIFT)
+/* For M profile only, Handler (ie not Thread) mode */
+#define ARM_TBFLAG_HANDLER_SHIFT    21
+#define ARM_TBFLAG_HANDLER_MASK     (1 << ARM_TBFLAG_HANDLER_SHIFT)
 
 /* Bit usage when in AArch64 state */
 #define ARM_TBFLAG_TBI0_SHIFT 0        /* TBI0 for EL0/1 or TBI for EL2/3 */
@@ -2326,6 +2330,8 @@ static inline bool arm_cpu_data_is_big_endian(CPUARMState *env)
     (((F) & ARM_TBFLAG_NS_MASK) >> ARM_TBFLAG_NS_SHIFT)
 #define ARM_TBFLAG_BE_DATA(F) \
     (((F) & ARM_TBFLAG_BE_DATA_MASK) >> ARM_TBFLAG_BE_DATA_SHIFT)
+#define ARM_TBFLAG_HANDLER(F) \
+    (((F) & ARM_TBFLAG_HANDLER_MASK) >> ARM_TBFLAG_HANDLER_SHIFT)
 #define ARM_TBFLAG_TBI0(F) \
     (((F) & ARM_TBFLAG_TBI0_MASK) >> ARM_TBFLAG_TBI0_SHIFT)
 #define ARM_TBFLAG_TBI1(F) \
@@ -2516,6 +2522,10 @@ static inline void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
     }
     *flags |= fp_exception_el(env) << ARM_TBFLAG_FPEXC_EL_SHIFT;
 
+    if (env->v7m.exception != 0) {
+        *flags |= ARM_TBFLAG_HANDLER_MASK;
+    }
+
     *cs_base = 0;
 }
 
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 8cb7a9451c..8a3e4480aa 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6271,6 +6271,25 @@ static void arm_log_exception(int idx)
 {
     if (qemu_loglevel_mask(CPU_LOG_INT)) {
         const char *exc = NULL;
+        static const char * const excnames[] = {
+            [EXCP_UDEF] = "Undefined Instruction",
+            [EXCP_SWI] = "SVC",
+            [EXCP_PREFETCH_ABORT] = "Prefetch Abort",
+            [EXCP_DATA_ABORT] = "Data Abort",
+            [EXCP_IRQ] = "IRQ",
+            [EXCP_FIQ] = "FIQ",
+            [EXCP_BKPT] = "Breakpoint",
+            [EXCP_EXCEPTION_EXIT] = "QEMU v7M exception exit",
+            [EXCP_KERNEL_TRAP] = "QEMU intercept of kernel commpage",
+            [EXCP_HVC] = "Hypervisor Call",
+            [EXCP_HYP_TRAP] = "Hypervisor Trap",
+            [EXCP_SMC] = "Secure Monitor Call",
+            [EXCP_VIRQ] = "Virtual IRQ",
+            [EXCP_VFIQ] = "Virtual FIQ",
+            [EXCP_SEMIHOST] = "Semihosting call",
+            [EXCP_NOCP] = "v7M NOCP UsageFault",
+            [EXCP_INVSTATE] = "v7M INVSTATE UsageFault",
+        };
 
         if (idx >= 0 && idx < ARRAY_SIZE(excnames)) {
             exc = excnames[idx];
diff --git a/target/arm/internals.h b/target/arm/internals.h
index f742a419ff..1f6efef7c4 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -51,27 +51,6 @@ static inline bool excp_is_internal(int excp)
         || excp == EXCP_SEMIHOST;
 }
 
-/* Exception names for debug logging; note that not all of these
- * precisely correspond to architectural exceptions.
- */
-static const char * const excnames[] = {
-    [EXCP_UDEF] = "Undefined Instruction",
-    [EXCP_SWI] = "SVC",
-    [EXCP_PREFETCH_ABORT] = "Prefetch Abort",
-    [EXCP_DATA_ABORT] = "Data Abort",
-    [EXCP_IRQ] = "IRQ",
-    [EXCP_FIQ] = "FIQ",
-    [EXCP_BKPT] = "Breakpoint",
-    [EXCP_EXCEPTION_EXIT] = "QEMU v7M exception exit",
-    [EXCP_KERNEL_TRAP] = "QEMU intercept of kernel commpage",
-    [EXCP_HVC] = "Hypervisor Call",
-    [EXCP_HYP_TRAP] = "Hypervisor Trap",
-    [EXCP_SMC] = "Secure Monitor Call",
-    [EXCP_VIRQ] = "Virtual IRQ",
-    [EXCP_VFIQ] = "Virtual FIQ",
-    [EXCP_SEMIHOST] = "Semihosting call",
-};
-
 /* Scale factor for generic timers, ie number of ns per tick.
  * This gives a 62.5MHz timer.
  */
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 61111091ad..a16abc8d12 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -940,7 +940,7 @@ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit)
              * single step at this point so something has gone wrong.
              */
             error_report("%s: guest single-step while debugging unsupported"
-                         " (%"PRIx64", %"PRIx32")\n",
+                         " (%"PRIx64", %"PRIx32")",
                          __func__, env->pc, debug_exit->hsr);
             return false;
         }
@@ -965,7 +965,7 @@ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit)
         break;
     }
     default:
-        error_report("%s: unhandled debug exit (%"PRIx32", %"PRIx64")\n",
+        error_report("%s: unhandled debug exit (%"PRIx32", %"PRIx64")",
                      __func__, debug_exit->hsr, env->pc);
     }
 
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index d64c8670fa..156b825040 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -130,7 +130,7 @@ void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
     if (unlikely(ret)) {
         ARMCPU *cpu = ARM_CPU(cs);
         CPUARMState *env = &cpu->env;
-        uint32_t syn, exc;
+        uint32_t syn, exc, fsc;
         unsigned int target_el;
         bool same_el;
 
@@ -145,19 +145,32 @@ void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
             env->cp15.hpfar_el2 = extract64(fi.s2addr, 12, 47) << 4;
         }
         same_el = arm_current_el(env) == target_el;
-        /* AArch64 syndrome does not have an LPAE bit */
-        syn = fsr & ~(1 << 9);
+
+        if (fsr & (1 << 9)) {
+            /* LPAE format fault status register : bottom 6 bits are
+             * status code in the same form as needed for syndrome
+             */
+            fsc = extract32(fsr, 0, 6);
+        } else {
+            /* Short format FSR : this fault will never actually be reported
+             * to an EL that uses a syndrome register. Check that here,
+             * and use a (currently) reserved FSR code in case the constructed
+             * syndrome does leak into the guest somehow.
+             */
+            assert(target_el != 2 && !arm_el_is_aa64(env, target_el));
+            fsc = 0x3f;
+        }
 
         /* For insn and data aborts we assume there is no instruction syndrome
          * information; this is always true for exceptions reported to EL1.
          */
         if (access_type == MMU_INST_FETCH) {
-            syn = syn_insn_abort(same_el, 0, fi.s1ptw, syn);
+            syn = syn_insn_abort(same_el, 0, fi.s1ptw, fsc);
             exc = EXCP_PREFETCH_ABORT;
         } else {
             syn = merge_syn_data_abort(env->exception.syndrome, target_el,
                                        same_el, fi.s1ptw,
-                                       access_type == MMU_DATA_STORE, syn);
+                                       access_type == MMU_DATA_STORE, fsc);
             if (access_type == MMU_DATA_STORE
                 && arm_feature(env, ARM_FEATURE_V6)) {
                 fsr |= (1 << 11);
diff --git a/target/arm/translate.c b/target/arm/translate.c
index e32e38cadd..0b5a0bca06 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -296,6 +296,30 @@ static void gen_step_complete_exception(DisasContext *s)
     s->is_jmp = DISAS_EXC;
 }
 
+static void gen_singlestep_exception(DisasContext *s)
+{
+    /* Generate the right kind of exception for singlestep, which is
+     * either the architectural singlestep or EXCP_DEBUG for QEMU's
+     * gdb singlestepping.
+     */
+    if (s->ss_active) {
+        gen_step_complete_exception(s);
+    } else {
+        gen_exception_internal(EXCP_DEBUG);
+    }
+}
+
+static inline bool is_singlestepping(DisasContext *s)
+{
+    /* Return true if we are singlestepping either because of
+     * architectural singlestep or QEMU gdbstub singlestep. This does
+     * not include the command line '-singlestep' mode which is rather
+     * misnamed as it only means "one instruction per TB" and doesn't
+     * affect the code we generate.
+     */
+    return s->singlestep_enabled || s->ss_active;
+}
+
 static void gen_smul_dual(TCGv_i32 a, TCGv_i32 b)
 {
     TCGv_i32 tmp1 = tcg_temp_new_i32();
@@ -880,6 +904,21 @@ static const uint8_t table_logic_cc[16] = {
     1, /* mvn */
 };
 
+static inline void gen_set_condexec(DisasContext *s)
+{
+    if (s->condexec_mask) {
+        uint32_t val = (s->condexec_cond << 4) | (s->condexec_mask >> 1);
+        TCGv_i32 tmp = tcg_temp_new_i32();
+        tcg_gen_movi_i32(tmp, val);
+        store_cpu_field(tmp, condexec_bits);
+    }
+}
+
+static inline void gen_set_pc_im(DisasContext *s, target_ulong val)
+{
+    tcg_gen_movi_i32(cpu_R[15], val);
+}
+
 /* Set PC and Thumb state from an immediate address.  */
 static inline void gen_bx_im(DisasContext *s, uint32_t addr)
 {
@@ -904,6 +943,51 @@ static inline void gen_bx(DisasContext *s, TCGv_i32 var)
     store_cpu_field(var, thumb);
 }
 
+/* Set PC and Thumb state from var. var is marked as dead.
+ * For M-profile CPUs, include logic to detect exception-return
+ * branches and handle them. This is needed for Thumb POP/LDM to PC, LDR to PC,
+ * and BX reg, and no others, and happens only for code in Handler mode.
+ */
+static inline void gen_bx_excret(DisasContext *s, TCGv_i32 var)
+{
+    /* Generate the same code here as for a simple bx, but flag via
+     * s->is_jmp that we need to do the rest of the work later.
+     */
+    gen_bx(s, var);
+    if (s->v7m_handler_mode && arm_dc_feature(s, ARM_FEATURE_M)) {
+        s->is_jmp = DISAS_BX_EXCRET;
+    }
+}
+
+static inline void gen_bx_excret_final_code(DisasContext *s)
+{
+    /* Generate the code to finish possible exception return and end the TB */
+    TCGLabel *excret_label = gen_new_label();
+
+    /* Is the new PC value in the magic range indicating exception return? */
+    tcg_gen_brcondi_i32(TCG_COND_GEU, cpu_R[15], 0xff000000, excret_label);
+    /* No: end the TB as we would for a DISAS_JMP */
+    if (is_singlestepping(s)) {
+        gen_singlestep_exception(s);
+    } else {
+        tcg_gen_exit_tb(0);
+    }
+    gen_set_label(excret_label);
+    /* Yes: this is an exception return.
+     * At this point in runtime env->regs[15] and env->thumb will hold
+     * the exception-return magic number, which do_v7m_exception_exit()
+     * will read. Nothing else will be able to see those values because
+     * the cpu-exec main loop guarantees that we will always go straight
+     * from raising the exception to the exception-handling code.
+     *
+     * gen_ss_advance(s) does nothing on M profile currently but
+     * calling it is conceptually the right thing as we have executed
+     * this instruction (compare SWI, HVC, SMC handling).
+     */
+    gen_ss_advance(s);
+    gen_exception_internal(EXCP_EXCEPTION_EXIT);
+}
+
 /* Variant of store_reg which uses branch&exchange logic when storing
    to r15 in ARM architecture v7 and above. The source must be a temporary
    and will be marked as dead. */
@@ -923,7 +1007,7 @@ static inline void store_reg_bx(DisasContext *s, int reg, TCGv_i32 var)
 static inline void store_reg_from_load(DisasContext *s, int reg, TCGv_i32 var)
 {
     if (reg == 15 && ENABLE_ARCH_5) {
-        gen_bx(s, var);
+        gen_bx_excret(s, var);
     } else {
         store_reg(s, reg, var);
     }
@@ -1056,11 +1140,6 @@ DO_GEN_ST(8, MO_UB)
 DO_GEN_ST(16, MO_UW)
 DO_GEN_ST(32, MO_UL)
 
-static inline void gen_set_pc_im(DisasContext *s, target_ulong val)
-{
-    tcg_gen_movi_i32(cpu_R[15], val);
-}
-
 static inline void gen_hvc(DisasContext *s, int imm16)
 {
     /* The pre HVC helper handles cases when HVC gets trapped
@@ -1094,17 +1173,6 @@ static inline void gen_smc(DisasContext *s)
     s->is_jmp = DISAS_SMC;
 }
 
-static inline void
-gen_set_condexec (DisasContext *s)
-{
-    if (s->condexec_mask) {
-        uint32_t val = (s->condexec_cond << 4) | (s->condexec_mask >> 1);
-        TCGv_i32 tmp = tcg_temp_new_i32();
-        tcg_gen_movi_i32(tmp, val);
-        store_cpu_field(tmp, condexec_bits);
-    }
-}
-
 static void gen_exception_internal_insn(DisasContext *s, int offset, int excp)
 {
     gen_set_condexec(s);
@@ -4092,7 +4160,7 @@ static inline void gen_goto_tb(DisasContext *s, int n, target_ulong dest)
 
 static inline void gen_jmp (DisasContext *s, uint32_t dest)
 {
-    if (unlikely(s->singlestep_enabled || s->ss_active)) {
+    if (unlikely(is_singlestepping(s))) {
         /* An indirect jump so that we still trigger the debug exception.  */
         if (s->thumb)
             dest |= 1;
@@ -9858,7 +9926,7 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
                         tmp = tcg_temp_new_i32();
                         gen_aa32_ld32u(s, tmp, addr, get_mem_index(s));
                         if (i == 15) {
-                            gen_bx(s, tmp);
+                            gen_bx_excret(s, tmp);
                         } else if (i == rn) {
                             loaded_var = tmp;
                             loaded_base = 1;
@@ -9959,7 +10027,7 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
             gen_arm_shift_reg(tmp, op, tmp2, logic_cc);
             if (logic_cc)
                 gen_logic_CC(tmp);
-            store_reg_bx(s, rd, tmp);
+            store_reg(s, rd, tmp);
             break;
         case 1: /* Sign/zero extend.  */
             op = (insn >> 20) & 7;
@@ -10485,7 +10553,12 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
                         }
                         break;
                     case 4: /* bxj */
-                        /* Trivial implementation equivalent to bx.  */
+                        /* Trivial implementation equivalent to bx.
+                         * This instruction doesn't exist at all for M-profile.
+                         */
+                        if (arm_dc_feature(s, ARM_FEATURE_M)) {
+                            goto illegal_op;
+                        }
                         tmp = load_reg(s, rn);
                         gen_bx(s, tmp);
                         break;
@@ -10885,7 +10958,7 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
                 goto illegal_op;
             }
             if (rs == 15) {
-                gen_bx(s, tmp);
+                gen_bx_excret(s, tmp);
             } else {
                 store_reg(s, rs, tmp);
             }
@@ -11075,9 +11148,11 @@ static void disas_thumb_insn(CPUARMState *env, DisasContext *s)
                     tmp2 = tcg_temp_new_i32();
                     tcg_gen_movi_i32(tmp2, val);
                     store_reg(s, 14, tmp2);
+                    gen_bx(s, tmp);
+                } else {
+                    /* Only BX works as exception-return, not BLX */
+                    gen_bx_excret(s, tmp);
                 }
-                /* already thumb, no need to check */
-                gen_bx(s, tmp);
                 break;
             }
             break;
@@ -11752,6 +11827,7 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
     dc->vec_len = ARM_TBFLAG_VECLEN(tb->flags);
     dc->vec_stride = ARM_TBFLAG_VECSTRIDE(tb->flags);
     dc->c15_cpar = ARM_TBFLAG_XSCALE_CPAR(tb->flags);
+    dc->v7m_handler_mode = ARM_TBFLAG_HANDLER(tb->flags);
     dc->cp_regs = cpu->cp_regs;
     dc->features = env->features;
 
@@ -11851,14 +11927,6 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             dc->is_jmp = DISAS_EXC;
             break;
         }
-#else
-        if (arm_dc_feature(dc, ARM_FEATURE_M)) {
-            /* Branches to the magic exception-return addresses should
-             * already have been caught via the arm_v7m_unassigned_access hook,
-             * and never get here.
-             */
-            assert(dc->pc < 0xfffffff0);
-        }
 #endif
 
         if (unlikely(!QTAILQ_EMPTY(&cs->breakpoints))) {
@@ -11953,9 +12021,8 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             ((dc->pc >= next_page_start - 3) && insn_crosses_page(env, dc));
 
     } while (!dc->is_jmp && !tcg_op_buf_full() &&
-             !cs->singlestep_enabled &&
+             !is_singlestepping(dc) &&
              !singlestep &&
-             !dc->ss_active &&
              !end_of_page &&
              num_insns < max_insns);
 
@@ -11971,9 +12038,16 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
     /* At this stage dc->condjmp will only be set when the skipped
        instruction was a conditional branch or trap, and the PC has
        already been written.  */
-    if (unlikely(cs->singlestep_enabled || dc->ss_active)) {
+    gen_set_condexec(dc);
+    if (dc->is_jmp == DISAS_BX_EXCRET) {
+        /* Exception return branches need some special case code at the
+         * end of the TB, which is complex enough that it has to
+         * handle the single-step vs not and the condition-failed
+         * insn codepath itself.
+         */
+        gen_bx_excret_final_code(dc);
+    } else if (unlikely(is_singlestepping(dc))) {
         /* Unconditional and "condition passed" instruction codepath. */
-        gen_set_condexec(dc);
         switch (dc->is_jmp) {
         case DISAS_SWI:
             gen_ss_advance(dc);
@@ -11993,24 +12067,8 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             gen_set_pc_im(dc, dc->pc);
             /* fall through */
         default:
-            if (dc->ss_active) {
-                gen_step_complete_exception(dc);
-            } else {
-                /* FIXME: Single stepping a WFI insn will not halt
-                   the CPU.  */
-                gen_exception_internal(EXCP_DEBUG);
-            }
-        }
-        if (dc->condjmp) {
-            /* "Condition failed" instruction codepath. */
-            gen_set_label(dc->condlabel);
-            gen_set_condexec(dc);
-            gen_set_pc_im(dc, dc->pc);
-            if (dc->ss_active) {
-                gen_step_complete_exception(dc);
-            } else {
-                gen_exception_internal(EXCP_DEBUG);
-            }
+            /* FIXME: Single stepping a WFI insn will not halt the CPU. */
+            gen_singlestep_exception(dc);
         }
     } else {
         /* While branches must always occur at the end of an IT block,
@@ -12021,7 +12079,6 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             - Hardware watchpoints.
            Hardware breakpoints have already been handled and skip this code.
          */
-        gen_set_condexec(dc);
         switch(dc->is_jmp) {
         case DISAS_NEXT:
             gen_goto_tb(dc, 1, dc->pc);
@@ -12061,11 +12118,17 @@ void gen_intermediate_code(CPUARMState *env, TranslationBlock *tb)
             gen_exception(EXCP_SMC, syn_aa32_smc(), 3);
             break;
         }
-        if (dc->condjmp) {
-            gen_set_label(dc->condlabel);
-            gen_set_condexec(dc);
+    }
+
+    if (dc->condjmp) {
+        /* "Condition failed" instruction codepath for the branch/trap insn */
+        gen_set_label(dc->condlabel);
+        gen_set_condexec(dc);
+        if (unlikely(is_singlestepping(dc))) {
+            gen_set_pc_im(dc, dc->pc);
+            gen_singlestep_exception(dc);
+        } else {
             gen_goto_tb(dc, 1, dc->pc);
-            dc->condjmp = 0;
         }
     }
 
diff --git a/target/arm/translate.h b/target/arm/translate.h
index abb0760158..629dab945e 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -31,6 +31,7 @@ typedef struct DisasContext {
     bool vfp_enabled; /* FP enabled via FPSCR.EN */
     int vec_len;
     int vec_stride;
+    bool v7m_handler_mode;
     /* Immediate value in AArch32 SVC insn; must be set if is_jmp == DISAS_SWI
      * so that top level loop can generate correct syndrome information.
      */
@@ -134,6 +135,10 @@ static void disas_set_insn_syndrome(DisasContext *s, uint32_t syn)
 #define DISAS_HVC 8
 #define DISAS_SMC 9
 #define DISAS_YIELD 10
+/* M profile branch which might be an exception return (and so needs
+ * custom end-of-TB code)
+ */
+#define DISAS_BX_EXCRET 11
 
 #ifdef TARGET_AARCH64
 void a64_translate_init(void);