alpha-linux-user: Handle TARGET_SSI_IEEE_RAISE_EXCEPTION properly

We weren't aggregating the exceptions, nor raising signals properly.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>

linux-user/syscall.c

@@ -7699,13 +7699,13 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         ret = -TARGET_EOPNOTSUPP;
         switch (arg1) {
           case TARGET_SSI_IEEE_FP_CONTROL:
-          case TARGET_SSI_IEEE_RAISE_EXCEPTION:
             {
                 uint64_t swcr, fpcr, orig_fpcr;
 
-                if (get_user_u64 (swcr, arg2))
+                if (get_user_u64 (swcr, arg2)) {
                     goto efault;
-                orig_fpcr = cpu_alpha_load_fpcr (cpu_env);
+                }
+                orig_fpcr = cpu_alpha_load_fpcr(cpu_env);
                 fpcr = orig_fpcr & FPCR_DYN_MASK;
 
                 /* Copied from linux ieee_swcr_to_fpcr.  */
@@ -7719,16 +7719,57 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
                 fpcr |= (swcr & SWCR_MAP_UMZ ? FPCR_UNDZ | FPCR_UNFD : 0);
                 fpcr |= (~swcr & SWCR_TRAP_ENABLE_DNO) << 41;
 
-                cpu_alpha_store_fpcr (cpu_env, fpcr);
+                cpu_alpha_store_fpcr(cpu_env, fpcr);
                 ret = 0;
+            }
+            break;
+
+          case TARGET_SSI_IEEE_RAISE_EXCEPTION:
+            {
+                uint64_t exc, fpcr, orig_fpcr;
+                int si_code;
+
+                if (get_user_u64(exc, arg2)) {
+                    goto efault;
+                }
 
-                if (arg1 == TARGET_SSI_IEEE_RAISE_EXCEPTION) {
-                    /* Old exceptions are not signaled.  */
-                    fpcr &= ~(orig_fpcr & FPCR_STATUS_MASK);
+                orig_fpcr = cpu_alpha_load_fpcr(cpu_env);
 
-                    /* If any exceptions set by this call, and are unmasked,
-                       send a signal.  */
-                    /* ??? FIXME */
+                /* We only add to the exception status here.  */
+                fpcr = orig_fpcr | ((exc & SWCR_STATUS_MASK) << 35);
+
+                cpu_alpha_store_fpcr(cpu_env, fpcr);
+                ret = 0;
+
+                /* Old exceptions are not signaled.  */
+                fpcr &= ~(orig_fpcr & FPCR_STATUS_MASK);
+
+                /* If any exceptions set by this call,
+                   and are unmasked, send a signal.  */
+                si_code = 0;
+                if ((fpcr & (FPCR_INE | FPCR_INED)) == FPCR_INE) {
+                    si_code = TARGET_FPE_FLTRES;
+                }
+                if ((fpcr & (FPCR_UNF | FPCR_UNFD)) == FPCR_UNF) {
+                    si_code = TARGET_FPE_FLTUND;
+                }
+                if ((fpcr & (FPCR_OVF | FPCR_OVFD)) == FPCR_OVF) {
+                    si_code = TARGET_FPE_FLTOVF;
+                }
+                if ((fpcr & (FPCR_DZE | FPCR_DZED)) == FPCR_DZE) {
+                    si_code = TARGET_FPE_FLTDIV;
+                }
+                if ((fpcr & (FPCR_INV | FPCR_INVD)) == FPCR_INV) {
+                    si_code = TARGET_FPE_FLTINV;
+                }
+                if (si_code != 0) {
+                    target_siginfo_t info;
+                    info.si_signo = SIGFPE;
+                    info.si_errno = 0;
+                    info.si_code = si_code;
+                    info._sifields._sigfault._addr
+                        = ((CPUArchState *)cpu_env)->pc;
+                    queue_signal((CPUArchState *)cpu_env, info.si_signo, &info);
                 }
             }
             break;