softfloat: Name rounding mode enum

Give the previously unnamed enum a typedef name.  Use the packed
attribute so that we do not affect the layout of the float_status
struct.  Use it in the prototypes of relevant functions.

Adjust switch statements as necessary to avoid compiler warnings.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

6 files changed, 66 insertions, 51 deletions

diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 65d457a548..93d8a03de6 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -759,6 +759,8 @@ static FloatParts round_canonical(FloatParts p, float_status *s,
                 case float_round_to_odd:
                     inc = frac & frac_lsb ? 0 : round_mask;
                     break;
+                default:
+                    break;
                 }
                 flags |= float_flag_inexact;
                 frac += inc;
@@ -1928,7 +1930,7 @@ float32 float64_to_float32(float64 a, float_status *s)
  * Arithmetic.
  */
 
-static FloatParts round_to_int(FloatParts a, int rmode,
+static FloatParts round_to_int(FloatParts a, FloatRoundMode rmode,
                                int scale, float_status *s)
 {
     switch (a.cls) {
@@ -2061,8 +2063,8 @@ float64 float64_round_to_int(float64 a, float_status *s)
  * is returned.
 */
 
-static int64_t round_to_int_and_pack(FloatParts in, int rmode, int scale,
-                                     int64_t min, int64_t max,
+static int64_t round_to_int_and_pack(FloatParts in, FloatRoundMode rmode,
+                                     int scale, int64_t min, int64_t max,
                                      float_status *s)
 {
     uint64_t r;
@@ -2107,63 +2109,63 @@ static int64_t round_to_int_and_pack(FloatParts in, int rmode, int scale,
     }
 }
 
-int16_t float16_to_int16_scalbn(float16 a, int rmode, int scale,
+int16_t float16_to_int16_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float16_unpack_canonical(a, s),
                                  rmode, scale, INT16_MIN, INT16_MAX, s);
 }
 
-int32_t float16_to_int32_scalbn(float16 a, int rmode, int scale,
+int32_t float16_to_int32_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float16_unpack_canonical(a, s),
                                  rmode, scale, INT32_MIN, INT32_MAX, s);
 }
 
-int64_t float16_to_int64_scalbn(float16 a, int rmode, int scale,
+int64_t float16_to_int64_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float16_unpack_canonical(a, s),
                                  rmode, scale, INT64_MIN, INT64_MAX, s);
 }
 
-int16_t float32_to_int16_scalbn(float32 a, int rmode, int scale,
+int16_t float32_to_int16_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float32_unpack_canonical(a, s),
                                  rmode, scale, INT16_MIN, INT16_MAX, s);
 }
 
-int32_t float32_to_int32_scalbn(float32 a, int rmode, int scale,
+int32_t float32_to_int32_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float32_unpack_canonical(a, s),
                                  rmode, scale, INT32_MIN, INT32_MAX, s);
 }
 
-int64_t float32_to_int64_scalbn(float32 a, int rmode, int scale,
+int64_t float32_to_int64_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float32_unpack_canonical(a, s),
                                  rmode, scale, INT64_MIN, INT64_MAX, s);
 }
 
-int16_t float64_to_int16_scalbn(float64 a, int rmode, int scale,
+int16_t float64_to_int16_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float64_unpack_canonical(a, s),
                                  rmode, scale, INT16_MIN, INT16_MAX, s);
 }
 
-int32_t float64_to_int32_scalbn(float64 a, int rmode, int scale,
+int32_t float64_to_int32_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float64_unpack_canonical(a, s),
                                  rmode, scale, INT32_MIN, INT32_MAX, s);
 }
 
-int64_t float64_to_int64_scalbn(float64 a, int rmode, int scale,
+int64_t float64_to_int64_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                 float_status *s)
 {
     return round_to_int_and_pack(float64_unpack_canonical(a, s),
@@ -2273,8 +2275,9 @@ int64_t float64_to_int64_round_to_zero(float64 a, float_status *s)
  *  flag.
  */
 
-static uint64_t round_to_uint_and_pack(FloatParts in, int rmode, int scale,
-                                       uint64_t max, float_status *s)
+static uint64_t round_to_uint_and_pack(FloatParts in, FloatRoundMode rmode,
+                                       int scale, uint64_t max,
+                                       float_status *s)
 {
     int orig_flags = get_float_exception_flags(s);
     FloatParts p = round_to_int(in, rmode, scale, s);
@@ -2319,63 +2322,63 @@ static uint64_t round_to_uint_and_pack(FloatParts in, int rmode, int scale,
     }
 }
 
-uint16_t float16_to_uint16_scalbn(float16 a, int rmode, int scale,
+uint16_t float16_to_uint16_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float16_unpack_canonical(a, s),
                                   rmode, scale, UINT16_MAX, s);
 }
 
-uint32_t float16_to_uint32_scalbn(float16 a, int rmode, int scale,
+uint32_t float16_to_uint32_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float16_unpack_canonical(a, s),
                                   rmode, scale, UINT32_MAX, s);
 }
 
-uint64_t float16_to_uint64_scalbn(float16 a, int rmode, int scale,
+uint64_t float16_to_uint64_scalbn(float16 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float16_unpack_canonical(a, s),
                                   rmode, scale, UINT64_MAX, s);
 }
 
-uint16_t float32_to_uint16_scalbn(float32 a, int rmode, int scale,
+uint16_t float32_to_uint16_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float32_unpack_canonical(a, s),
                                   rmode, scale, UINT16_MAX, s);
 }
 
-uint32_t float32_to_uint32_scalbn(float32 a, int rmode, int scale,
+uint32_t float32_to_uint32_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float32_unpack_canonical(a, s),
                                   rmode, scale, UINT32_MAX, s);
 }
 
-uint64_t float32_to_uint64_scalbn(float32 a, int rmode, int scale,
+uint64_t float32_to_uint64_scalbn(float32 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float32_unpack_canonical(a, s),
                                   rmode, scale, UINT64_MAX, s);
 }
 
-uint16_t float64_to_uint16_scalbn(float64 a, int rmode, int scale,
+uint16_t float64_to_uint16_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float64_unpack_canonical(a, s),
                                   rmode, scale, UINT16_MAX, s);
 }
 
-uint32_t float64_to_uint32_scalbn(float64 a, int rmode, int scale,
+uint32_t float64_to_uint32_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float64_unpack_canonical(a, s),
                                   rmode, scale, UINT32_MAX, s);
 }
 
-uint64_t float64_to_uint64_scalbn(float64 a, int rmode, int scale,
+uint64_t float64_to_uint64_scalbn(float64 a, FloatRoundMode rmode, int scale,
                                   float_status *s)
 {
     return round_to_uint_and_pack(float64_unpack_canonical(a, s),
@@ -5715,6 +5718,11 @@ floatx80 floatx80_round_to_int(floatx80 a, float_status *status)
             return
                   aSign ? packFloatx80( 1, 0, 0 )
                 : packFloatx80( 0, 0x3FFF, UINT64_C(0x8000000000000000));
+
+        case float_round_to_zero:
+            break;
+        default:
+            g_assert_not_reached();
         }
         return packFloatx80( aSign, 0, 0 );
     }
@@ -7047,6 +7055,9 @@ float128 float128_round_to_int(float128 a, float_status *status)
 
             case float_round_to_odd:
                 return packFloat128(aSign, 0x3FFF, 0, 0);
+
+            case float_round_to_zero:
+                break;
             }
             return packFloat128( aSign, 0, 0, 0 );
         }
diff --git a/include/fpu/softfloat-helpers.h b/include/fpu/softfloat-helpers.h
index 40d32a6d5d..735ed6b653 100644
--- a/include/fpu/softfloat-helpers.h
+++ b/include/fpu/softfloat-helpers.h
@@ -58,7 +58,8 @@ static inline void set_float_detect_tininess(bool val, float_status *status)
     status->tininess_before_rounding = val;
 }
 
-static inline void set_float_rounding_mode(int val, float_status *status)
+static inline void set_float_rounding_mode(FloatRoundMode val,
+                                           float_status *status)
 {
     status->float_rounding_mode = val;
 }
@@ -99,7 +100,7 @@ static inline bool get_float_detect_tininess(float_status *status)
     return status->tininess_before_rounding;
 }
 
-static inline int get_float_rounding_mode(float_status *status)
+static inline FloatRoundMode get_float_rounding_mode(float_status *status)
 {
     return status->float_rounding_mode;
 }
diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h
index 874ddd9f93..7680193ebc 100644
--- a/include/fpu/softfloat-types.h
+++ b/include/fpu/softfloat-types.h
@@ -123,7 +123,7 @@ typedef struct {
  *Software IEC/IEEE floating-point rounding mode.
  */
 
-enum {
+typedef enum __attribute__((__packed__)) {
     float_round_nearest_even = 0,
     float_round_down         = 1,
     float_round_up           = 2,
@@ -131,7 +131,7 @@ enum {
     float_round_ties_away    = 4,
     /* Not an IEEE rounding mode: round to the closest odd mantissa value */
     float_round_to_odd       = 5,
-};
+} FloatRoundMode;
 
 /*
  * Software IEC/IEEE floating-point exception flags.
@@ -156,7 +156,7 @@ enum {
  */
 
 typedef struct float_status {
-    signed char float_rounding_mode;
+    FloatRoundMode float_rounding_mode;
     uint8_t     float_exception_flags;
     signed char floatx80_rounding_precision;
     bool tininess_before_rounding;
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 3f588da7c7..ca75f764aa 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -186,9 +186,9 @@ float32 float16_to_float32(float16, bool ieee, float_status *status);
 float16 float64_to_float16(float64 a, bool ieee, float_status *status);
 float64 float16_to_float64(float16 a, bool ieee, float_status *status);
 
-int16_t float16_to_int16_scalbn(float16, int, int, float_status *status);
-int32_t float16_to_int32_scalbn(float16, int, int, float_status *status);
-int64_t float16_to_int64_scalbn(float16, int, int, float_status *status);
+int16_t float16_to_int16_scalbn(float16, FloatRoundMode, int, float_status *);
+int32_t float16_to_int32_scalbn(float16, FloatRoundMode, int, float_status *);
+int64_t float16_to_int64_scalbn(float16, FloatRoundMode, int, float_status *);
 
 int16_t float16_to_int16(float16, float_status *status);
 int32_t float16_to_int32(float16, float_status *status);
@@ -198,9 +198,12 @@ int16_t float16_to_int16_round_to_zero(float16, float_status *status);
 int32_t float16_to_int32_round_to_zero(float16, float_status *status);
 int64_t float16_to_int64_round_to_zero(float16, float_status *status);
 
-uint16_t float16_to_uint16_scalbn(float16 a, int, int, float_status *status);
-uint32_t float16_to_uint32_scalbn(float16 a, int, int, float_status *status);
-uint64_t float16_to_uint64_scalbn(float16 a, int, int, float_status *status);
+uint16_t float16_to_uint16_scalbn(float16 a, FloatRoundMode,
+                                  int, float_status *status);
+uint32_t float16_to_uint32_scalbn(float16 a, FloatRoundMode,
+                                  int, float_status *status);
+uint64_t float16_to_uint64_scalbn(float16 a, FloatRoundMode,
+                                  int, float_status *status);
 
 uint16_t float16_to_uint16(float16 a, float_status *status);
 uint32_t float16_to_uint32(float16 a, float_status *status);
@@ -298,9 +301,9 @@ float16 float16_default_nan(float_status *status);
 | Software IEC/IEEE single-precision conversion routines.
 *----------------------------------------------------------------------------*/
 
-int16_t float32_to_int16_scalbn(float32, int, int, float_status *status);
-int32_t float32_to_int32_scalbn(float32, int, int, float_status *status);
-int64_t float32_to_int64_scalbn(float32, int, int, float_status *status);
+int16_t float32_to_int16_scalbn(float32, FloatRoundMode, int, float_status *);
+int32_t float32_to_int32_scalbn(float32, FloatRoundMode, int, float_status *);
+int64_t float32_to_int64_scalbn(float32, FloatRoundMode, int, float_status *);
 
 int16_t float32_to_int16(float32, float_status *status);
 int32_t float32_to_int32(float32, float_status *status);
@@ -310,9 +313,9 @@ int16_t float32_to_int16_round_to_zero(float32, float_status *status);
 int32_t float32_to_int32_round_to_zero(float32, float_status *status);
 int64_t float32_to_int64_round_to_zero(float32, float_status *status);
 
-uint16_t float32_to_uint16_scalbn(float32, int, int, float_status *status);
-uint32_t float32_to_uint32_scalbn(float32, int, int, float_status *status);
-uint64_t float32_to_uint64_scalbn(float32, int, int, float_status *status);
+uint16_t float32_to_uint16_scalbn(float32, FloatRoundMode, int, float_status *);
+uint32_t float32_to_uint32_scalbn(float32, FloatRoundMode, int, float_status *);
+uint64_t float32_to_uint64_scalbn(float32, FloatRoundMode, int, float_status *);
 
 uint16_t float32_to_uint16(float32, float_status *status);
 uint32_t float32_to_uint32(float32, float_status *status);
@@ -455,9 +458,9 @@ float32 float32_default_nan(float_status *status);
 | Software IEC/IEEE double-precision conversion routines.
 *----------------------------------------------------------------------------*/
 
-int16_t float64_to_int16_scalbn(float64, int, int, float_status *status);
-int32_t float64_to_int32_scalbn(float64, int, int, float_status *status);
-int64_t float64_to_int64_scalbn(float64, int, int, float_status *status);
+int16_t float64_to_int16_scalbn(float64, FloatRoundMode, int, float_status *);
+int32_t float64_to_int32_scalbn(float64, FloatRoundMode, int, float_status *);
+int64_t float64_to_int64_scalbn(float64, FloatRoundMode, int, float_status *);
 
 int16_t float64_to_int16(float64, float_status *status);
 int32_t float64_to_int32(float64, float_status *status);
@@ -467,9 +470,9 @@ int16_t float64_to_int16_round_to_zero(float64, float_status *status);
 int32_t float64_to_int32_round_to_zero(float64, float_status *status);
 int64_t float64_to_int64_round_to_zero(float64, float_status *status);
 
-uint16_t float64_to_uint16_scalbn(float64, int, int, float_status *status);
-uint32_t float64_to_uint32_scalbn(float64, int, int, float_status *status);
-uint64_t float64_to_uint64_scalbn(float64, int, int, float_status *status);
+uint16_t float64_to_uint16_scalbn(float64, FloatRoundMode, int, float_status *);
+uint32_t float64_to_uint32_scalbn(float64, FloatRoundMode, int, float_status *);
+uint64_t float64_to_uint64_scalbn(float64, FloatRoundMode, int, float_status *);
 
 uint16_t float64_to_uint16(float64, float_status *status);
 uint32_t float64_to_uint32(float64, float_status *status);
diff --git a/target/arm/vfp_helper.c b/target/arm/vfp_helper.c
index 42625747d1..0920694764 100644
--- a/target/arm/vfp_helper.c
+++ b/target/arm/vfp_helper.c
@@ -697,9 +697,9 @@ static bool round_to_inf(float_status *fpst, bool sign_bit)
         return sign_bit;
     case float_round_to_zero: /* Round to Zero */
         return false;
+    default:
+        g_assert_not_reached();
     }
-
-    g_assert_not_reached();
 }
 
 uint32_t HELPER(recpe_f16)(uint32_t input, void *fpstp)
diff --git a/target/m68k/fpu_helper.c b/target/m68k/fpu_helper.c
index 4137542ec0..36e6c704d1 100644
--- a/target/m68k/fpu_helper.c
+++ b/target/m68k/fpu_helper.c
@@ -149,7 +149,7 @@ void cpu_m68k_set_fpcr(CPUM68KState *env, uint32_t val)
 
 void HELPER(fitrunc)(CPUM68KState *env, FPReg *res, FPReg *val)
 {
-    int rounding_mode = get_float_rounding_mode(&env->fp_status);
+    FloatRoundMode rounding_mode = get_float_rounding_mode(&env->fp_status);
     set_float_rounding_mode(float_round_to_zero, &env->fp_status);
     res->d = floatx80_round_to_int(val->d, &env->fp_status);
     set_float_rounding_mode(rounding_mode, &env->fp_status);
@@ -300,7 +300,7 @@ void HELPER(fdmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 
 void HELPER(fsglmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 {
-    int rounding_mode = get_float_rounding_mode(&env->fp_status);
+    FloatRoundMode rounding_mode = get_float_rounding_mode(&env->fp_status);
     floatx80 a, b;
 
     PREC_BEGIN(32);
@@ -333,7 +333,7 @@ void HELPER(fddiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 
 void HELPER(fsgldiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 {
-    int rounding_mode = get_float_rounding_mode(&env->fp_status);
+    FloatRoundMode rounding_mode = get_float_rounding_mode(&env->fp_status);
     floatx80 a, b;
 
     PREC_BEGIN(32);