fpu/softfloat: Pass FloatClass to pickNaNMulAdd

For each operand, pass a single enumeration instead of a pair of booleans.
The commit also merges multiple different ifdef-selected implementations
of pickNaNMulAdd into a single function whose body is ifdef-selected.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

fpu/softfloat-specialize.h

@@ -594,41 +594,35 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls,
 | information.
 | Return values : 0 : a; 1 : b; 2 : c; 3 : default-NaN
 *----------------------------------------------------------------------------*/
-#if defined(TARGET_ARM)
-static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
-                         flag cIsQNaN, flag cIsSNaN, flag infzero,
-                         float_status *status)
+static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls,
+                         bool infzero, float_status *status)
 {
+#if defined(TARGET_ARM)
     /* For ARM, the (inf,zero,qnan) case sets InvalidOp and returns
      * the default NaN
      */
-    if (infzero && cIsQNaN) {
+    if (infzero && is_qnan(c_cls)) {
         float_raise(float_flag_invalid, status);
         return 3;
     }
 
     /* This looks different from the ARM ARM pseudocode, because the ARM ARM
      * puts the operands to a fused mac operation (a*b)+c in the order c,a,b.
      */
-    if (cIsSNaN) {
+    if (is_snan(c_cls)) {
         return 2;
-    } else if (aIsSNaN) {
+    } else if (is_snan(a_cls)) {
         return 0;
-    } else if (bIsSNaN) {
+    } else if (is_snan(b_cls)) {
         return 1;
-    } else if (cIsQNaN) {
+    } else if (is_qnan(c_cls)) {
         return 2;
-    } else if (aIsQNaN) {
+    } else if (is_qnan(a_cls)) {
         return 0;
     } else {
         return 1;
     }
-}
 #elif defined(TARGET_MIPS)
-static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
-                         flag cIsQNaN, flag cIsSNaN, flag infzero,
-                         float_status *status)
-{
     /* For MIPS, the (inf,zero,qnan) case sets InvalidOp and returns
      * the default NaN
      */
@@ -639,41 +633,36 @@ static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
 
     if (snan_bit_is_one(status)) {
         /* Prefer sNaN over qNaN, in the a, b, c order. */
-        if (aIsSNaN) {
+        if (is_snan(a_cls)) {
             return 0;
-        } else if (bIsSNaN) {
+        } else if (is_snan(b_cls)) {
             return 1;
-        } else if (cIsSNaN) {
+        } else if (is_snan(c_cls)) {
             return 2;
-        } else if (aIsQNaN) {
+        } else if (is_qnan(a_cls)) {
             return 0;
-        } else if (bIsQNaN) {
+        } else if (is_qnan(b_cls)) {
             return 1;
         } else {
             return 2;
         }
     } else {
         /* Prefer sNaN over qNaN, in the c, a, b order. */
-        if (cIsSNaN) {
+        if (is_snan(c_cls)) {
             return 2;
-        } else if (aIsSNaN) {
+        } else if (is_snan(a_cls)) {
             return 0;
-        } else if (bIsSNaN) {
+        } else if (is_snan(b_cls)) {
             return 1;
-        } else if (cIsQNaN) {
+        } else if (is_qnan(c_cls)) {
             return 2;
-        } else if (aIsQNaN) {
+        } else if (is_qnan(a_cls)) {
             return 0;
         } else {
             return 1;
         }
     }
-}
 #elif defined(TARGET_PPC)
-static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
-                         flag cIsQNaN, flag cIsSNaN, flag infzero,
-                         float_status *status)
-{
     /* For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer
      * to return an input NaN if we have one (ie c) rather than generating
      * a default NaN
@@ -686,31 +675,26 @@ static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
     /* If fRA is a NaN return it; otherwise if fRB is a NaN return it;
      * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB
      */
-    if (aIsSNaN || aIsQNaN) {
+    if (is_nan(a_cls)) {
         return 0;
-    } else if (cIsSNaN || cIsQNaN) {
+    } else if (is_nan(c_cls)) {
         return 2;
     } else {
         return 1;
     }
-}
 #else
-/* A default implementation: prefer a to b to c.
- * This is unlikely to actually match any real implementation.
- */
-static int pickNaNMulAdd(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
-                         flag cIsQNaN, flag cIsSNaN, flag infzero,
-                         float_status *status)
-{
-    if (aIsSNaN || aIsQNaN) {
+    /* A default implementation: prefer a to b to c.
+     * This is unlikely to actually match any real implementation.
+     */
+    if (is_nan(a_cls)) {
         return 0;
-    } else if (bIsSNaN || bIsQNaN) {
+    } else if (is_nan(b_cls)) {
         return 1;
     } else {
         return 2;
     }
-}
 #endif
+}
 
 /*----------------------------------------------------------------------------
 | Takes two single-precision floating-point values `a' and `b', one of which

fpu/softfloat.c

@@ -601,10 +601,7 @@ static FloatParts pick_nan_muladd(FloatParts a, FloatParts b, FloatParts c,
         s->float_exception_flags |= float_flag_invalid;
     }
 
-    which = pickNaNMulAdd(is_qnan(a.cls), is_snan(a.cls),
-                          is_qnan(b.cls), is_snan(b.cls),
-                          is_qnan(c.cls), is_snan(c.cls),
-                          inf_zero, s);
+    which = pickNaNMulAdd(a.cls, b.cls, c.cls, inf_zero, s);
 
     if (s->default_nan_mode) {
         /* Note that this check is after pickNaNMulAdd so that function