more cases of 80 floats that should be 64 (dlang#21888)

Author: WalterBright

compiler/src/dmd/glue/e2ir.d

@@ -4627,7 +4627,7 @@ elem* toElemCast(CastExp ce, elem* e, bool isLvalue, ref IRState irs)
              * information available to do it.
              *
              * Casting from a C++ interface to a non-C++ interface
-             * always results in null because there's no way one
+             * always results in null because there is no way one
              * can be derived from the other.
              */
             e = el_bin(OPcomma, TYnptr, e, el_long(TYnptr, 0));
@@ -4660,6 +4660,9 @@ elem* toElemCast(CastExp ce, elem* e, bool isLvalue, ref IRState irs)
     if (ftym == ttym)
         return Lret(ce, e);
 
+    // OSX AArch64 long doubles are 64 bits
+    bool RealIsDouble = target.os == Target.os.OSX && target.isAArch64;
+
     /* Reduce combinatorial explosion by rewriting the 'to' and 'from' types to a
      * generic equivalent (as far as casting goes)
      */
@@ -4676,6 +4679,10 @@ elem* toElemCast(CastExp ce, elem* e, bool isLvalue, ref IRState irs)
         case Tdchar:    tty = Tuns32;   break;
         case Tvoid:     return Lpaint(ce, e, ttym);
 
+        case Tfloat80:          if (RealIsDouble) tty = Tfloat64;     break;
+        case Timaginary80:      if (RealIsDouble) tty = Timaginary64; break;
+        case Tcomplex80:        if (RealIsDouble) tty = Tcomplex64;   break;
+
         case Tbool:
         {
             // Construct e?true:false
@@ -4703,6 +4710,10 @@ elem* toElemCast(CastExp ce, elem* e, bool isLvalue, ref IRState irs)
         case Tnoreturn:
             return Lret(ce, e);
 
+        case Tfloat80:          if (RealIsDouble) fty = Tfloat64;     break;
+        case Timaginary80:      if (RealIsDouble) fty = Timaginary64; break;
+        case Tcomplex80:        if (RealIsDouble) fty = Tcomplex64;   break;
+
         default:
             break;
     }

compiler/src/dmd/glue/package.d

@@ -239,7 +239,7 @@ Symbol* getBzeroSymbol()
 tym_t totym(Type tx)
 {
     // OSX AArch64 long doubles are 64 bits
-    bool OSXAArch64 = target.os == Target.os.OSX && target.isAArch64;
+    bool RealIsDouble = target.os == Target.os.OSX && target.isAArch64;
 
     tym_t t;
     switch (tx.ty)
@@ -255,13 +255,13 @@ tym_t totym(Type tx)
         case Tuns64:    t = TYullong;   break;
         case Tfloat32:  t = TYfloat;    break;
         case Tfloat64:  t = TYdouble;   break;
-        case Tfloat80:  t = OSXAArch64 ? TYdouble : TYldouble;  break;
+        case Tfloat80:  t = RealIsDouble ? TYdouble : TYldouble;  break;
         case Timaginary32: t = TYifloat; break;
         case Timaginary64: t = TYidouble; break;
-        case Timaginary80: t = OSXAArch64 ? TYidouble : TYildouble; break;
+        case Timaginary80: t = RealIsDouble ? TYidouble : TYildouble; break;
         case Tcomplex32: t = TYcfloat;  break;
         case Tcomplex64: t = TYcdouble; break;
-        case Tcomplex80: t = OSXAArch64 ? TYcdouble : TYcldouble; break;
+        case Tcomplex80: t = RealIsDouble ? TYcdouble : TYcldouble; break;
         case Tbool:     t = TYbool;     break;
         case Tchar:     t = TYchar;     break;
         case Twchar:    t = TYwchar_t;  break;