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Diffstat (limited to 'target/s390x/fpu_helper.c')
-rw-r--r--target/s390x/fpu_helper.c541
1 files changed, 330 insertions, 211 deletions
diff --git a/target/s390x/fpu_helper.c b/target/s390x/fpu_helper.c
index e921172bc4..1be68bafea 100644
--- a/target/s390x/fpu_helper.c
+++ b/target/s390x/fpu_helper.c
@@ -36,13 +36,21 @@
 
 #define RET128(F) (env->retxl = F.low, F.high)
 
-#define convert_bit(mask, from, to) \
-    (to < from                      \
-     ? (mask / (from / to)) & to    \
-     : (mask & from) * (to / from))
+uint8_t s390_softfloat_exc_to_ieee(unsigned int exc)
+{
+    uint8_t s390_exc = 0;
+
+    s390_exc |= (exc & float_flag_invalid) ? S390_IEEE_MASK_INVALID : 0;
+    s390_exc |= (exc & float_flag_divbyzero) ? S390_IEEE_MASK_DIVBYZERO : 0;
+    s390_exc |= (exc & float_flag_overflow) ? S390_IEEE_MASK_OVERFLOW : 0;
+    s390_exc |= (exc & float_flag_underflow) ? S390_IEEE_MASK_UNDERFLOW : 0;
+    s390_exc |= (exc & float_flag_inexact) ? S390_IEEE_MASK_INEXACT : 0;
+
+    return s390_exc;
+}
 
 /* Should be called after any operation that may raise IEEE exceptions.  */
-static void handle_exceptions(CPUS390XState *env, uintptr_t retaddr)
+static void handle_exceptions(CPUS390XState *env, bool XxC, uintptr_t retaddr)
 {
     unsigned s390_exc, qemu_exc;
 
@@ -53,22 +61,54 @@ static void handle_exceptions(CPUS390XState *env, uintptr_t retaddr)
         return;
     }
     env->fpu_status.float_exception_flags = 0;
+    s390_exc = s390_softfloat_exc_to_ieee(qemu_exc);
+
+    /*
+     * IEEE-Underflow exception recognition exists if a tininess condition
+     * (underflow) exists and
+     * - The mask bit in the FPC is zero and the result is inexact
+     * - The mask bit in the FPC is one
+     * So tininess conditions that are not inexact don't trigger any
+     * underflow action in case the mask bit is not one.
+     */
+    if (!(s390_exc & S390_IEEE_MASK_INEXACT) &&
+        !((env->fpc >> 24) & S390_IEEE_MASK_UNDERFLOW)) {
+        s390_exc &= ~S390_IEEE_MASK_UNDERFLOW;
+    }
 
-    /* Convert softfloat exception bits to s390 exception bits.  */
-    s390_exc = 0;
-    s390_exc |= convert_bit(qemu_exc, float_flag_invalid, 0x80);
-    s390_exc |= convert_bit(qemu_exc, float_flag_divbyzero, 0x40);
-    s390_exc |= convert_bit(qemu_exc, float_flag_overflow, 0x20);
-    s390_exc |= convert_bit(qemu_exc, float_flag_underflow, 0x10);
-    s390_exc |= convert_bit(qemu_exc, float_flag_inexact, 0x08);
-
-    /* Install the exceptions that we raised.  */
-    env->fpc |= s390_exc << 16;
+    /*
+     * FIXME:
+     * 1. Right now, all inexact conditions are inidicated as
+     *    "truncated" (0) and never as "incremented" (1) in the DXC.
+     * 2. Only traps due to invalid/divbyzero are suppressing. Other traps
+     *    are completing, meaning the target register has to be written!
+     *    This, however will mean that we have to write the register before
+     *    triggering the trap - impossible right now.
+     */
+
+    /*
+     * invalid/divbyzero cannot coexist with other conditions.
+     * overflow/underflow however can coexist with inexact, we have to
+     * handle it separatly.
+     */
+    if (s390_exc & ~S390_IEEE_MASK_INEXACT) {
+        if (s390_exc & ~S390_IEEE_MASK_INEXACT & env->fpc >> 24) {
+            /* trap condition - inexact reported along */
+            tcg_s390_data_exception(env, s390_exc, retaddr);
+        }
+        /* nontrap condition - inexact handled differently */
+        env->fpc |= (s390_exc & ~S390_IEEE_MASK_INEXACT) << 16;
+    }
 
-    /* Send signals for enabled exceptions.  */
-    s390_exc &= env->fpc >> 24;
-    if (s390_exc) {
-        tcg_s390_data_exception(env, s390_exc, retaddr);
+    /* inexact handling */
+    if (s390_exc & S390_IEEE_MASK_INEXACT && !XxC) {
+        /* trap condition - overflow/underflow _not_ reported along */
+        if (s390_exc & S390_IEEE_MASK_INEXACT & env->fpc >> 24) {
+            tcg_s390_data_exception(env, s390_exc & S390_IEEE_MASK_INEXACT,
+                                    retaddr);
+        }
+        /* nontrap condition */
+        env->fpc |= (s390_exc & S390_IEEE_MASK_INEXACT) << 16;
     }
 }
 
@@ -130,11 +170,22 @@ uint32_t set_cc_nz_f128(float128 v)
     }
 }
 
+static inline uint8_t round_from_m34(uint32_t m34)
+{
+    return extract32(m34, 0, 4);
+}
+
+static inline bool xxc_from_m34(uint32_t m34)
+{
+    /* XxC is bit 1 of m4 */
+    return extract32(m34, 4 + 3 - 1, 1);
+}
+
 /* 32-bit FP addition */
 uint64_t HELPER(aeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float32 ret = float32_add(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -142,7 +193,7 @@ uint64_t HELPER(aeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint64_t HELPER(adb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float64 ret = float64_add(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -153,7 +204,7 @@ uint64_t HELPER(axb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     float128 ret = float128_add(make_float128(ah, al),
                                 make_float128(bh, bl),
                                 &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -161,7 +212,7 @@ uint64_t HELPER(axb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 uint64_t HELPER(seb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float32 ret = float32_sub(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -169,7 +220,7 @@ uint64_t HELPER(seb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint64_t HELPER(sdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float64 ret = float64_sub(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -180,7 +231,7 @@ uint64_t HELPER(sxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     float128 ret = float128_sub(make_float128(ah, al),
                                 make_float128(bh, bl),
                                 &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -188,7 +239,7 @@ uint64_t HELPER(sxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 uint64_t HELPER(deb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float32 ret = float32_div(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -196,7 +247,7 @@ uint64_t HELPER(deb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint64_t HELPER(ddb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float64 ret = float64_div(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -207,7 +258,7 @@ uint64_t HELPER(dxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     float128 ret = float128_div(make_float128(ah, al),
                                 make_float128(bh, bl),
                                 &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -215,7 +266,7 @@ uint64_t HELPER(dxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 uint64_t HELPER(meeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float32 ret = float32_mul(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -223,7 +274,7 @@ uint64_t HELPER(meeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint64_t HELPER(mdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float64 ret = float64_mul(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -232,7 +283,7 @@ uint64_t HELPER(mdeb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     float64 ret = float32_to_float64(f2, &env->fpu_status);
     ret = float64_mul(f1, ret, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -243,7 +294,7 @@ uint64_t HELPER(mxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     float128 ret = float128_mul(make_float128(ah, al),
                                 make_float128(bh, bl),
                                 &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -253,7 +304,7 @@ uint64_t HELPER(mxdb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 {
     float128 ret = float64_to_float128(f2, &env->fpu_status);
     ret = float128_mul(make_float128(ah, al), ret, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -261,15 +312,19 @@ uint64_t HELPER(mxdb)(CPUS390XState *env, uint64_t ah, uint64_t al,
 uint64_t HELPER(ldeb)(CPUS390XState *env, uint64_t f2)
 {
     float64 ret = float32_to_float64(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 64-bit float */
-uint64_t HELPER(ldxb)(CPUS390XState *env, uint64_t ah, uint64_t al)
+uint64_t HELPER(ldxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
+                      uint32_t m34)
 {
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float64 ret = float128_to_float64(make_float128(ah, al), &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
@@ -277,7 +332,7 @@ uint64_t HELPER(ldxb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 uint64_t HELPER(lxdb)(CPUS390XState *env, uint64_t f2)
 {
     float128 ret = float64_to_float128(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
@@ -285,23 +340,30 @@ uint64_t HELPER(lxdb)(CPUS390XState *env, uint64_t f2)
 uint64_t HELPER(lxeb)(CPUS390XState *env, uint64_t f2)
 {
     float128 ret = float32_to_float128(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
 /* convert 64-bit float to 32-bit float */
-uint64_t HELPER(ledb)(CPUS390XState *env, uint64_t f2)
+uint64_t HELPER(ledb)(CPUS390XState *env, uint64_t f2, uint32_t m34)
 {
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float32 ret = float64_to_float32(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 32-bit float */
-uint64_t HELPER(lexb)(CPUS390XState *env, uint64_t ah, uint64_t al)
+uint64_t HELPER(lexb)(CPUS390XState *env, uint64_t ah, uint64_t al,
+                      uint32_t m34)
 {
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float32 ret = float128_to_float32(make_float128(ah, al), &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
@@ -309,7 +371,7 @@ uint64_t HELPER(lexb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 uint32_t HELPER(ceb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     int cmp = float32_compare_quiet(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
@@ -317,7 +379,7 @@ uint32_t HELPER(ceb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint32_t HELPER(cdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     int cmp = float64_compare_quiet(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
@@ -328,21 +390,28 @@ uint32_t HELPER(cxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     int cmp = float128_compare_quiet(make_float128(ah, al),
                                      make_float128(bh, bl),
                                      &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
-static int swap_round_mode(CPUS390XState *env, int m3)
+int s390_swap_bfp_rounding_mode(CPUS390XState *env, int m3)
 {
     int ret = env->fpu_status.float_rounding_mode;
+
     switch (m3) {
     case 0:
         /* current mode */
         break;
     case 1:
-        /* biased round no nearest */
+        /* round to nearest with ties away from 0 */
+        set_float_rounding_mode(float_round_ties_away, &env->fpu_status);
+        break;
+    case 3:
+        /* round to prepare for shorter precision */
+        set_float_rounding_mode(float_round_to_odd, &env->fpu_status);
+        break;
     case 4:
-        /* round to nearest */
+        /* round to nearest with ties to even */
         set_float_rounding_mode(float_round_nearest_even, &env->fpu_status);
         break;
     case 5:
@@ -357,226 +426,251 @@ static int swap_round_mode(CPUS390XState *env, int m3)
         /* round to -inf */
         set_float_rounding_mode(float_round_down, &env->fpu_status);
         break;
+    default:
+        g_assert_not_reached();
     }
     return ret;
 }
 
+void s390_restore_bfp_rounding_mode(CPUS390XState *env, int old_mode)
+{
+    set_float_rounding_mode(old_mode, &env->fpu_status);
+}
+
 /* convert 64-bit int to 32-bit float */
-uint64_t HELPER(cegb)(CPUS390XState *env, int64_t v2, uint32_t m3)
+uint64_t HELPER(cegb)(CPUS390XState *env, int64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float32 ret = int64_to_float32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit int to 64-bit float */
-uint64_t HELPER(cdgb)(CPUS390XState *env, int64_t v2, uint32_t m3)
+uint64_t HELPER(cdgb)(CPUS390XState *env, int64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float64 ret = int64_to_float64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit int to 128-bit float */
-uint64_t HELPER(cxgb)(CPUS390XState *env, int64_t v2, uint32_t m3)
+uint64_t HELPER(cxgb)(CPUS390XState *env, int64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float128 ret = int64_to_float128(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return RET128(ret);
 }
 
 /* convert 64-bit uint to 32-bit float */
-uint64_t HELPER(celgb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(celgb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float32 ret = uint64_to_float32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit uint to 64-bit float */
-uint64_t HELPER(cdlgb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cdlgb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float64 ret = uint64_to_float64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit uint to 128-bit float */
-uint64_t HELPER(cxlgb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cxlgb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float128 ret = uint64_to_float128(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return RET128(ret);
 }
 
 /* convert 32-bit float to 64-bit int */
-uint64_t HELPER(cgeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cgeb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     int64_t ret = float32_to_int64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit float to 64-bit int */
-uint64_t HELPER(cgdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cgdb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     int64_t ret = float64_to_int64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 64-bit int */
-uint64_t HELPER(cgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
+uint64_t HELPER(cgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float128 v2 = make_float128(h, l);
     int64_t ret = float128_to_int64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 32-bit float to 32-bit int */
-uint64_t HELPER(cfeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cfeb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     int32_t ret = float32_to_int32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit float to 32-bit int */
-uint64_t HELPER(cfdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(cfdb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     int32_t ret = float64_to_int32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 32-bit int */
-uint64_t HELPER(cfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
+uint64_t HELPER(cfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float128 v2 = make_float128(h, l);
     int32_t ret = float128_to_int32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 32-bit float to 64-bit uint */
-uint64_t HELPER(clgeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(clgeb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     uint64_t ret;
+
     v2 = float32_to_float64(v2, &env->fpu_status);
     ret = float64_to_uint64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit float to 64-bit uint */
-uint64_t HELPER(clgdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(clgdb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     uint64_t ret = float64_to_uint64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 64-bit uint */
-uint64_t HELPER(clgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
+uint64_t HELPER(clgxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
-    float128 v2 = make_float128(h, l);
-    /* ??? Not 100% correct.  */
-    uint64_t ret = float128_to_int64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
+    uint64_t ret = float128_to_uint64(make_float128(h, l), &env->fpu_status);
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 32-bit float to 32-bit uint */
-uint64_t HELPER(clfeb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(clfeb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     uint32_t ret = float32_to_uint32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 64-bit float to 32-bit uint */
-uint64_t HELPER(clfdb)(CPUS390XState *env, uint64_t v2, uint32_t m3)
+uint64_t HELPER(clfdb)(CPUS390XState *env, uint64_t v2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     uint32_t ret = float64_to_uint32(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* convert 128-bit float to 32-bit uint */
-uint64_t HELPER(clfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m3)
+uint64_t HELPER(clfxb)(CPUS390XState *env, uint64_t h, uint64_t l, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
-    float128 v2 = make_float128(h, l);
-    /* Not 100% correct.  */
-    uint32_t ret = float128_to_int64(v2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
+    uint32_t ret = float128_to_uint32(make_float128(h, l), &env->fpu_status);
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* round to integer 32-bit */
-uint64_t HELPER(fieb)(CPUS390XState *env, uint64_t f2, uint32_t m3)
+uint64_t HELPER(fieb)(CPUS390XState *env, uint64_t f2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float32 ret = float32_round_to_int(f2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* round to integer 64-bit */
-uint64_t HELPER(fidb)(CPUS390XState *env, uint64_t f2, uint32_t m3)
+uint64_t HELPER(fidb)(CPUS390XState *env, uint64_t f2, uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float64 ret = float64_round_to_int(f2, &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return ret;
 }
 
 /* round to integer 128-bit */
-uint64_t HELPER(fixb)(CPUS390XState *env, uint64_t ah, uint64_t al, uint32_t m3)
+uint64_t HELPER(fixb)(CPUS390XState *env, uint64_t ah, uint64_t al,
+                      uint32_t m34)
 {
-    int hold = swap_round_mode(env, m3);
+    int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
     float128 ret = float128_round_to_int(make_float128(ah, al),
                                          &env->fpu_status);
-    set_float_rounding_mode(hold, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+
+    s390_restore_bfp_rounding_mode(env, old_mode);
+    handle_exceptions(env, xxc_from_m34(m34), GETPC());
     return RET128(ret);
 }
 
@@ -584,7 +678,7 @@ uint64_t HELPER(fixb)(CPUS390XState *env, uint64_t ah, uint64_t al, uint32_t m3)
 uint32_t HELPER(keb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     int cmp = float32_compare(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
@@ -592,7 +686,7 @@ uint32_t HELPER(keb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 uint32_t HELPER(kdb)(CPUS390XState *env, uint64_t f1, uint64_t f2)
 {
     int cmp = float64_compare(f1, f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
@@ -603,7 +697,7 @@ uint32_t HELPER(kxb)(CPUS390XState *env, uint64_t ah, uint64_t al,
     int cmp = float128_compare(make_float128(ah, al),
                                make_float128(bh, bl),
                                &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return float_comp_to_cc(env, cmp);
 }
 
@@ -612,7 +706,7 @@ uint64_t HELPER(maeb)(CPUS390XState *env, uint64_t f1,
                       uint64_t f2, uint64_t f3)
 {
     float32 ret = float32_muladd(f2, f3, f1, 0, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -621,7 +715,7 @@ uint64_t HELPER(madb)(CPUS390XState *env, uint64_t f1,
                       uint64_t f2, uint64_t f3)
 {
     float64 ret = float64_muladd(f2, f3, f1, 0, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -631,7 +725,7 @@ uint64_t HELPER(mseb)(CPUS390XState *env, uint64_t f1,
 {
     float32 ret = float32_muladd(f2, f3, f1, float_muladd_negate_c,
                                  &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -641,78 +735,63 @@ uint64_t HELPER(msdb)(CPUS390XState *env, uint64_t f1,
 {
     float64 ret = float64_muladd(f2, f3, f1, float_muladd_negate_c,
                                  &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
+/* The rightmost bit has the number 11. */
+static inline uint16_t dcmask(int bit, bool neg)
+{
+    return 1 << (11 - bit - neg);
+}
+
+#define DEF_FLOAT_DCMASK(_TYPE) \
+static uint16_t _TYPE##_dcmask(CPUS390XState *env, _TYPE f1)       \
+{                                                                  \
+    const bool neg = _TYPE##_is_neg(f1);                           \
+                                                                   \
+    /* Sorted by most common cases - only one class is possible */ \
+    if (_TYPE##_is_normal(f1)) {                                   \
+        return dcmask(2, neg);                                     \
+    } else if (_TYPE##_is_zero(f1)) {                              \
+        return dcmask(0, neg);                                     \
+    } else if (_TYPE##_is_denormal(f1)) {                          \
+        return dcmask(4, neg);                                     \
+    } else if (_TYPE##_is_infinity(f1)) {                          \
+        return dcmask(6, neg);                                     \
+    } else if (_TYPE##_is_quiet_nan(f1, &env->fpu_status)) {       \
+        return dcmask(8, neg);                                     \
+    }                                                              \
+    /* signaling nan, as last remaining case */                    \
+    return dcmask(10, neg);                                        \
+}
+DEF_FLOAT_DCMASK(float32)
+DEF_FLOAT_DCMASK(float64)
+DEF_FLOAT_DCMASK(float128)
+
 /* test data class 32-bit */
 uint32_t HELPER(tceb)(CPUS390XState *env, uint64_t f1, uint64_t m2)
 {
-    float32 v1 = f1;
-    int neg = float32_is_neg(v1);
-    uint32_t cc = 0;
-
-    if ((float32_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
-        (float32_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
-        (float32_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
-        (float32_is_signaling_nan(v1, &env->fpu_status) &&
-         (m2 & (1 << (1-neg))))) {
-        cc = 1;
-    } else if (m2 & (1 << (9-neg))) {
-        /* assume normalized number */
-        cc = 1;
-    }
-    /* FIXME: denormalized? */
-    return cc;
+    return (m2 & float32_dcmask(env, f1)) != 0;
 }
 
 /* test data class 64-bit */
 uint32_t HELPER(tcdb)(CPUS390XState *env, uint64_t v1, uint64_t m2)
 {
-    int neg = float64_is_neg(v1);
-    uint32_t cc = 0;
-
-    if ((float64_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
-        (float64_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
-        (float64_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
-        (float64_is_signaling_nan(v1, &env->fpu_status) &&
-         (m2 & (1 << (1-neg))))) {
-        cc = 1;
-    } else if (m2 & (1 << (9-neg))) {
-        /* assume normalized number */
-        cc = 1;
-    }
-    /* FIXME: denormalized? */
-    return cc;
+    return (m2 & float64_dcmask(env, v1)) != 0;
 }
 
 /* test data class 128-bit */
-uint32_t HELPER(tcxb)(CPUS390XState *env, uint64_t ah,
-                      uint64_t al, uint64_t m2)
-{
-    float128 v1 = make_float128(ah, al);
-    int neg = float128_is_neg(v1);
-    uint32_t cc = 0;
-
-    if ((float128_is_zero(v1) && (m2 & (1 << (11-neg)))) ||
-        (float128_is_infinity(v1) && (m2 & (1 << (5-neg)))) ||
-        (float128_is_any_nan(v1) && (m2 & (1 << (3-neg)))) ||
-        (float128_is_signaling_nan(v1, &env->fpu_status) &&
-         (m2 & (1 << (1-neg))))) {
-        cc = 1;
-    } else if (m2 & (1 << (9-neg))) {
-        /* assume normalized number */
-        cc = 1;
-    }
-    /* FIXME: denormalized? */
-    return cc;
+uint32_t HELPER(tcxb)(CPUS390XState *env, uint64_t ah, uint64_t al, uint64_t m2)
+{
+    return (m2 & float128_dcmask(env, make_float128(ah, al))) != 0;
 }
 
 /* square root 32-bit */
 uint64_t HELPER(sqeb)(CPUS390XState *env, uint64_t f2)
 {
     float32 ret = float32_sqrt(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -720,7 +799,7 @@ uint64_t HELPER(sqeb)(CPUS390XState *env, uint64_t f2)
 uint64_t HELPER(sqdb)(CPUS390XState *env, uint64_t f2)
 {
     float64 ret = float64_sqrt(f2, &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return ret;
 }
 
@@ -728,44 +807,84 @@ uint64_t HELPER(sqdb)(CPUS390XState *env, uint64_t f2)
 uint64_t HELPER(sqxb)(CPUS390XState *env, uint64_t ah, uint64_t al)
 {
     float128 ret = float128_sqrt(make_float128(ah, al), &env->fpu_status);
-    handle_exceptions(env, GETPC());
+    handle_exceptions(env, false, GETPC());
     return RET128(ret);
 }
 
-static const int fpc_to_rnd[4] = {
+static const int fpc_to_rnd[8] = {
     float_round_nearest_even,
     float_round_to_zero,
     float_round_up,
-    float_round_down
+    float_round_down,
+    -1,
+    -1,
+    -1,
+    float_round_to_odd,
 };
 
 /* set fpc */
 void HELPER(sfpc)(CPUS390XState *env, uint64_t fpc)
 {
+    if (fpc_to_rnd[fpc & 0x7] == -1 || fpc & 0x03030088u ||
+        (!s390_has_feat(S390_FEAT_FLOATING_POINT_EXT) && fpc & 0x4)) {
+        s390_program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO, GETPC());
+    }
+
     /* Install everything in the main FPC.  */
     env->fpc = fpc;
 
     /* Install the rounding mode in the shadow fpu_status.  */
-    set_float_rounding_mode(fpc_to_rnd[fpc & 3], &env->fpu_status);
+    set_float_rounding_mode(fpc_to_rnd[fpc & 0x7], &env->fpu_status);
 }
 
 /* set fpc and signal */
-void HELPER(sfas)(CPUS390XState *env, uint64_t val)
+void HELPER(sfas)(CPUS390XState *env, uint64_t fpc)
 {
     uint32_t signalling = env->fpc;
-    uint32_t source = val;
     uint32_t s390_exc;
 
-    /* The contents of the source operand are placed in the FPC register;
-       then the flags in the FPC register are set to the logical OR of the
-       signalling flags and the source flags.  */
-    env->fpc = source | (signalling & 0x00ff0000);
-    set_float_rounding_mode(fpc_to_rnd[source & 3], &env->fpu_status);
+    if (fpc_to_rnd[fpc & 0x7] == -1 || fpc & 0x03030088u ||
+        (!s390_has_feat(S390_FEAT_FLOATING_POINT_EXT) && fpc & 0x4)) {
+        s390_program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO, GETPC());
+    }
 
-    /* If any signalling flag is 1 and the corresponding source mask
-       is also 1, a simulated-iee-exception trap occurs.  */
-    s390_exc = (signalling >> 16) & (source >> 24);
+    /*
+     * FPC is set to the FPC operand with a bitwise OR of the signalling
+     * flags.
+     */
+    env->fpc = fpc | (signalling & 0x00ff0000);
+    set_float_rounding_mode(fpc_to_rnd[fpc & 0x7], &env->fpu_status);
+
+    /*
+     * If any signaling flag is enabled in the new FPC mask, a
+     * simulated-iee-exception exception occurs.
+     */
+    s390_exc = (signalling >> 16) & (fpc >> 24);
     if (s390_exc) {
+        if (s390_exc & S390_IEEE_MASK_INVALID) {
+            s390_exc = S390_IEEE_MASK_INVALID;
+        } else if (s390_exc & S390_IEEE_MASK_DIVBYZERO) {
+            s390_exc = S390_IEEE_MASK_DIVBYZERO;
+        } else if (s390_exc & S390_IEEE_MASK_OVERFLOW) {
+            s390_exc &= (S390_IEEE_MASK_OVERFLOW | S390_IEEE_MASK_INEXACT);
+        } else if (s390_exc & S390_IEEE_MASK_UNDERFLOW) {
+            s390_exc &= (S390_IEEE_MASK_UNDERFLOW | S390_IEEE_MASK_INEXACT);
+        } else if (s390_exc & S390_IEEE_MASK_INEXACT) {
+            s390_exc = S390_IEEE_MASK_INEXACT;
+        } else if (s390_exc & S390_IEEE_MASK_QUANTUM) {
+            s390_exc = S390_IEEE_MASK_QUANTUM;
+        }
         tcg_s390_data_exception(env, s390_exc | 3, GETPC());
     }
 }
+
+/* set bfp rounding mode */
+void HELPER(srnm)(CPUS390XState *env, uint64_t rnd)
+{
+    if (rnd > 0x7 || fpc_to_rnd[rnd & 0x7] == -1) {
+        s390_program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO, GETPC());
+    }
+
+    env->fpc = deposit32(env->fpc, 0, 3, rnd);
+    set_float_rounding_mode(fpc_to_rnd[rnd & 0x7], &env->fpu_status);
+}