[PATCH v2 08/30] bsd-user/arm/target_arch_cpu.h: Implement trivial EXCP exceptions

[Warner Losh <imp@bsdimp.com>]

Implement EXCP_UDEF, EXCP_DEBUG, EXCP_INTERRUPT, EXCP_ATOMIC and
EXCP_YIELD. The first two generate a signal to the emulated
binary. EXCP_ATOMIC handles atomic operations. The remainder are fancy
nops.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Mikaël Urankar <mikael.urankar@gmail.com>
Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
---
 bsd-user/arm/target_arch_cpu.h | 58 ++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/bsd-user/arm/target_arch_cpu.h b/bsd-user/arm/target_arch_cpu.h
index 2484bdc2f7..609b78b4e2 100644
--- a/bsd-user/arm/target_arch_cpu.h
+++ b/bsd-user/arm/target_arch_cpu.h
@@ -48,6 +48,64 @@ static inline void target_cpu_loop(CPUARMState *env)
         cpu_exec_end(cs);
         process_queued_cpu_work(cs);
         switch (trapnr) {
+        case EXCP_UDEF:
+            {
+                /* See arm/arm/undefined.c undefinedinstruction(); */
+                info.si_addr = env->regs[15];
+
+                /*
+                 * Make sure the PC is correctly aligned. (It should
+                 * be.)
+                 */
+                if ((info.si_addr & 3) != 0) {
+                    info.si_signo = TARGET_SIGILL;
+                    info.si_errno = 0;
+                    info.si_code = TARGET_ILL_ILLADR;
+                    queue_signal(env, info.si_signo, &info);
+                } else {
+                    int rc = 0;
+#ifdef NOT_YET
+                    uint32_t opcode;
+
+                    /*
+                     * Get the opcode.
+                     *
+                     * FIXME - what to do if get_user() fails?
+                     */
+                    get_user_u32(opcode, env->regs[15]);
+
+                    /* Check the opcode with CP handlers we may have. */
+                    rc = EmulateAll(opcode, &ts->fpa, env);
+#endif /* NOT_YET */
+                    if (rc == 0) {
+                        /* illegal instruction */
+                        info.si_signo = TARGET_SIGILL;
+                        info.si_errno = 0;
+                        info.si_code = TARGET_ILL_ILLOPC;
+                        queue_signal(env, info.si_signo, &info);
+                    }
+                }
+            }
+            break;
+        case EXCP_INTERRUPT:
+            /* just indicate that signals should be handled asap */
+            break;
+        case EXCP_DEBUG:
+            {
+
+                info.si_signo = TARGET_SIGTRAP;
+                info.si_errno = 0;
+                info.si_code = TARGET_TRAP_BRKPT;
+                info.si_addr = env->exception.vaddress;
+                queue_signal(env, info.si_signo, &info);
+            }
+            break;
+        case EXCP_ATOMIC:
+            cpu_exec_step_atomic(cs);
+            break;
+        case EXCP_YIELD:
+            /* nothing to do here for user-mode, just resume guest code */
+            break;
         default:
             fprintf(stderr, "qemu: unhandled CPU exception 0x%x - aborting\n",
                     trapnr);
-- 
2.33.0