MODULE--------------------------------------------- public access procedures ---; IMPORT M3ID, Target, TargetMap, TInt, TWord; REVEAL (* private methods of the types *) T = ROOT BRANDED "M3Type.T" OBJECT METHODS get_info (VAR(*OUT*) x: Info) RAISES {Error}; base (): T; is_ordinal () : BOOLEAN; get_bounds (VAR(*OUT*) min, max: Target.Int): BOOLEAN; (****** is_equal (b: T): BOOLEAN; is_subtype (b: T): BOOLEAN; ******) END; EXCEPTION Error (TEXT); M3Type
PROCEDURE**************************** NOT IMPLEMENTED ***************************GetInfo (t: T; VAR(*OUT*) x: Info) = BEGIN TRY x.err_msg := NIL; t.get_info (x); EXCEPT Error (msg) => x.class := Class.Unknown; x.err_msg := msg; END; END GetInfo; PROCEDUREBase (t: T): T = BEGIN RETURN t.base (); END Base; PROCEDUREIsOrdinal (t: T): BOOLEAN = BEGIN RETURN t.is_ordinal (); END IsOrdinal; PROCEDURENumber (t: T): Target.Int = VAR min, max, tmp: Target.Int; BEGIN IF t.get_bounds (min, max) AND TInt.Subtract (max, min, tmp) AND TInt.Add (tmp, TInt.One, max) THEN RETURN max; END; RETURN Target.Integer.max; END Number; PROCEDUREGetBounds (t: T; VAR min, max: Target.Int): BOOLEAN = BEGIN RETURN t.get_bounds (min, max); END GetBounds; PROCEDUREIsEqual (a, b: T): BOOLEAN = BEGIN RETURN (a = b); (* OR a.is_equal (b) *) END IsEqual;
PROCEDURE IsSubtype (a, b: T): BOOLEAN = BEGIN RETURN a.is_subtype (b); END IsSubtype;
PROCEDURE IsAssignable (a, b: T; safe: BOOLEAN): BOOLEAN = VAR i, e: T; min_a, max_a, min_b, max_b, min, max: Target.Int; BEGIN IF IsEqual (a, b) OR IsSubtype (b, a) THEN RETURN TRUE; ELSIF IsOrdinal (a) THEN (* ordinal types: OK if there is a common supertype and they have at least one member in common.
IF IsEqual (Base(a), Base(b), NIL) AND GetBounds (a, min_a, max_a) AND GetBounds (b, min_b, max_b) THEN (* check for a non-empty intersection *) min := min_a; IF TInt.LT (min, min_b) THEN min := min_b; END; max := max_a; IF TInt.LT (max_b, max) THEN max := max_b; END; RETURN TInt.LE (min, max); ELSE RETURN FALSE; END; ELSIF IsSubtype (a, b) THEN (* may be ok, but must narrow rhs before doing the assignment *) RETURN IsSubtype (b, Refany) OR ArrayType.Split (b, i, e) OR (IsSubtype (b, Address) AND (NOT safe OR NOT IsEqual (b, Addr.T))); ELSE RETURN FALSE; END; END IsAssignable; ***************************** NOT IMPLEMENTED ***************************)--------------------------------------------------------------- ARRAY ---
TYPE PublicArray = T OBJECT index : T; element : T; END; REVEAL Array = PublicArray BRANDED "M3Type.Array" OBJECT OVERRIDES get_info := GetArrayInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; (********************** is_equal := ArrayEQ; is_subtype := ArraySubtype; **********************) END; PROCEDURE**************************** NOT IMPLEMENTED ******************************GetArrayInfo (self: Array; VAR x: Info) RAISES {Error} = VAR elt : Info; n_elts : INTEGER; align : INTEGER; full_size : INTEGER; elt_pack : INTEGER; total_size : INTEGER; packed : BOOLEAN; BEGIN self.element.get_info (elt); IF NOT IsOrdinal (self.index) THEN Err ("array index type must be an ordinal type"); END; IF (elt.class = Class.OpenArray) THEN Err ("array element type cannot be an open array"); END; IF NOT TInt.ToInt (Number (self.index), n_elts) THEN Restrict ("array has too many elements"); END; align := elt.alignment; elt_pack := elt.size; IF (elt.class # Class.Packed) THEN (* naturally aligned elements must be OK *) elt_pack := (elt.size + align - 1) DIV align * align; packed := FALSE; ELSE (* find a packing that's allowed *) (* align := FindAlignment (p); *) packed := (elt_pack < Target.Byte) OR (elt_pack MOD align # 0); END; IF (n_elts > 0) AND (elt_pack > 0) AND (n_elts > LAST (INTEGER) DIV elt_pack) THEN Restrict ("array type too large"); END; full_size := elt_pack * n_elts; total_size := RoundUp (full_size, align); x.size := total_size; x.min_size := total_size; x.alignment := align; x.class := Class.Array; x.is_traced := elt.is_traced; x.is_empty := elt.is_empty; x.is_solid := elt.is_solid AND (elt_pack <= elt.size) AND (total_size <= full_size); END GetArrayInfo;
PROCEDURE ArrayEQ (a: Array; b: T): BOOLEAN = BEGIN TYPECASE b OF
Array (bb) => RETURN IsEqual (a.element, bb.element)AND IsEqual (a.index, bb.index); ELSE RETURN FALSE; END; END ArrayEQ;
PROCEDURE ArraySubtype (a: Array; tb: T): BOOLEAN = VAR ta, eb: T; b: Array; BEGIN ta := a;
(* peel off the fixed dimensions of A and open dimensions of B
LOOP a := ReduceArray (ta); IF (a = NIL) OR NOT OpenArrayType.Split (tb, eb) THEN EXIT END; ta := a.element; tb := eb; END; (* peel off the fixed dimensions as long as the sizes are equal *) LOOP a := ReduceArray (ta); b := ReduceArray (tb); IF (a = NIL) OR (b = NIL) THEN EXIT END; IF (a.index # b.index) THEN IF Number (a.index) # Number (b.index) THEN RETURN FALSE END; END; ta := a.element; tb := b.element; END; RETURN IsEqual (ta, tb); END ArraySubtype; PROCEDURE ReduceArray (t: T): Array = BEGIN TYPE t OF | NULL => RETURN NIL; | Array (a) => RETURN a; ELSE RETURN NIL; END; END ReduceArray; ***************************** NOT IMPLEMENTED ******************************)-------------------------------------------------------- Enumerations ---
TYPE PublicEnum = T OBJECT elements : REF ARRAY OF M3ID.T; END; REVEAL Enum = PublicEnum BRANDED "M3Type.Enum" OBJECT OVERRIDES get_info := GetEnumInfo; base := SelfBase; is_ordinal := IsAlways; get_bounds := EnumBounds; (*********************** is_equal := EnumEQ; is_subtype := EnumEQ; ***********************) END; PROCEDURE**************************** NOT IMPLEMENTED ****************************** PROCEDURE EnumEQ (a: Enum; tb: T): BOOLEAN = BEGIN TYPECASE tb OFGetEnumInfo (self: Enum; VAR x: Info) RAISES {Error} = VAR n_elts := NUMBER (self.elements^); max: Target.Int; rep: EnumRep; BEGIN IF NOT TInt.FromInt (n_elts-1, max) THEN Err ("enumeration type too large"); END; rep := FindEnumRep (max); x.min_size := MinEnumSize (n_elts); x.size := TargetMap.Word_types[rep].size; x.alignment := TargetMap.Word_types[rep].align; x.class := Class.Enum; x.is_traced := FALSE; x.is_empty := (n_elts <= 0); x.is_solid := TRUE; END GetEnumInfo; TYPE EnumRep = [FIRST (TargetMap.Word_types) .. LAST (TargetMap.Word_types)]; PROCEDUREFindEnumRep (READONLY max: Target.Int): EnumRep = BEGIN FOR i := FIRST (EnumRep) TO LAST (EnumRep) DO WITH t = TargetMap.Word_types[i] DO IF (t.size <= Target.Word.size) AND TInt.LE (max, t.max) THEN RETURN i; END; END; END; RETURN LAST (EnumRep); END FindEnumRep; PROCEDUREMinEnumSize (n_elts: INTEGER): INTEGER = VAR i, j: INTEGER; BEGIN j := 1; i := 2; WHILE (n_elts > i) DO INC (j); INC (i, i); END; RETURN j; END MinEnumSize; PROCEDUREEnumBounds (self: Enum; VAR min, max: Target.Int): BOOLEAN = VAR b: BOOLEAN; BEGIN min := TInt.Zero; b := TInt.FromInt (NUMBER (self.elements^) - 1, max); <*ASSERT b*> RETURN TRUE; END EnumBounds;
Enum (b) =>IF NUMBER (a.elements^) # NUMBER (b.elements^) THEN RETURN FALSE; END; FOR i := 0 TO LAST (a.elements^) DO IF (a.elements[i] # b.elements[i]) THEN RETURN FALSE; END; END; RETURN TRUE; ELSE RETURN FALSE END; END EnumEQ; ***************************** NOT IMPLEMENTED *****************************
-------------------------------------------------------------- OBJECT ---
TYPE PublicObject = T OBJECT brand : TEXT; super : T; fields : REF ARRAY OF FieldDesc; methods : REF ARRAY OF MethodDesc; overrides : REF ARRAY OF MethodDesc; END; REVEAL Object = PublicObject BRANDED "M3Type.Object" OBJECT OVERRIDES get_info := GetObjectInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE------------------------------------------------------------- Opaques ---GetObjectInfo (self: Object; VAR x: Info) RAISES {Error} = VAR traced: BOOLEAN; sup: Info; BEGIN IF (self = Root) THEN traced := TRUE; ELSIF (self = UntracedRoot) THEN traced := FALSE; ELSE self.super.get_info (sup); traced := sup.is_traced; END; x.size := Target.Address.size; x.min_size := Target.Address.size; x.alignment := Target.Address.align; x.class := Class.Object; x.is_traced := traced; x.is_empty := FALSE; x.is_solid := TRUE; END GetObjectInfo;
TYPE PublicOpaque = T OBJECT super : T; END; REVEAL Opaque = PublicOpaque BRANDED "M3Type.Opaque" OBJECT OVERRIDES get_info := GetOpaqueInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE---------------------------------------------------------- OPEN ARRAY ---GetOpaqueInfo (self: Opaque; VAR x: Info) RAISES {Error} = VAR sup: Info; BEGIN self.super.get_info (sup); x.size := Target.Address.size; x.min_size := Target.Address.size; x.alignment := Target.Address.align; x.class := Class.Opaque; x.is_traced := sup.is_traced; x.is_empty := FALSE; x.is_solid := TRUE; END GetOpaqueInfo;
TYPE PublicOpenArray = T OBJECT element : T; END; REVEAL OpenArray = PublicOpenArray BRANDED "M3Type.OpenArray" OBJECT OVERRIDES get_info := GetOpenArrayInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE--------------------------------------------------- Packed (BITS FOR) ---GetOpenArrayInfo (self: OpenArray; VAR x: Info) RAISES {Error} = VAR elt : Info; elt_pack : INTEGER; align : INTEGER; MinAlign := MAX (MAX (Target.Byte, Target.Structure_size_boundary), MAX (Target.Address.align, Target.Integer.align)); BEGIN self.element.get_info (elt); align := elt.alignment; IF (elt.class = Class.Packed) THEN elt_pack := NARROW (self.element, Packed).bits; ELSE (* naturally aligned elements must be OK *) elt_pack := (elt.size + align - 1) DIV align * align; END; align := MAX (align, MinAlign); (* == whole array alignment *) IF (elt_pack MOD Target.Byte) # 0 THEN Restrict ("open array elements must be byte-aligned"); (***** ELSIF NOT Type.IsAlignedOk (p, align) THEN Restrict ("scalars in packed array elements cannot cross word boundaries"); ****) END; x.size := -1; x.min_size := -1; x.alignment := align; x.class := Class.OpenArray; x.is_traced := elt.is_traced; x.is_empty := elt.is_empty; x.is_solid := elt.is_solid AND (elt_pack <= elt.size); END GetOpenArrayInfo;
TYPE PublicPacked = T OBJECT bits : INTEGER; element : T; END; REVEAL Packed = PublicPacked BRANDED "M3Type.Packed" OBJECT OVERRIDES get_info := GetPackedInfo; base := PackedBase; is_ordinal := PackedOrd; get_bounds := PackedBounds; END; PROCEDURE----------------------------------------------------------- PROCEDURE ---GetPackedInfo (self: Packed; VAR x: Info) RAISES {Error} = VAR elt: Info; BEGIN self.element.get_info (elt); x.size := self.bits; x.min_size := self.bits; x.alignment := elt.alignment; x.class := Class.Packed; x.is_traced := elt.is_traced; x.is_empty := elt.is_empty; x.is_solid := elt.is_solid; END GetPackedInfo; PROCEDUREPackedBase (self: Packed): T = BEGIN RETURN self.element; END PackedBase; PROCEDUREPackedOrd (self: Packed): BOOLEAN = BEGIN RETURN IsOrdinal (self.element); END PackedOrd; PROCEDUREPackedBounds (self: Packed; VAR min, max: Target.Int): BOOLEAN = BEGIN RETURN GetBounds (self.element, min, max); END PackedBounds;
TYPE PublicProcedure = T OBJECT formals : REF ARRAY OF FormalDesc; return : T; raises : REF ARRAY OF ExceptDesc; callingConv : Target.CallingConvention; END; REVEAL Procedure = PublicProcedure BRANDED "M3Type.Procedure" OBJECT OVERRIDES get_info := GetProcInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE-------------------------------------------------------------- RECORD ---GetProcInfo (<*UNUSED*> self: Procedure; VAR x: Info) = BEGIN x.size := Target.Address.size; x.min_size := Target.Address.size; x.alignment := Target.Address.align; x.class := Class.Procedure; x.is_traced := FALSE; x.is_empty := FALSE; x.is_solid := TRUE; END GetProcInfo;
TYPE PublicRecord = T OBJECT fields : REF ARRAY OF FieldDesc; END; REVEAL Record = PublicRecord BRANDED "M3Type.Record" OBJECT OVERRIDES get_info := GetRecordInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE----------------------------------------------------------------- REF ---GetRecordInfo (self: Record; VAR x: Info) RAISES {Error} = VAR size, align: INTEGER; solid: BOOLEAN; BEGIN FieldSizeAndAlignment (self.fields, size, align, solid); x.size := size; x.min_size := size; x.alignment := align; x.class := Class.Record; x.is_traced := FALSE; x.is_empty := FALSE; x.is_solid := solid; END GetRecordInfo; PROCEDUREFieldSizeAndAlignment (fields: REF ARRAY OF FieldDesc; VAR(*OUT*) recSize, recAlign: INTEGER; VAR(*OUT*) is_solid: BOOLEAN) RAISES {Error} = VAR fieldAlign : INTEGER; fieldSize : INTEGER; anyPacked := FALSE; info : Info; newSize : INTEGER; newAlign : INTEGER; curSize : INTEGER; BEGIN (* compute the size of the record *) newSize := 0; (* total size of the record *) newAlign := Target.Structure_size_boundary; (* minimum allowed alignment *) is_solid := TRUE; FOR i := 0 TO LAST (fields^) DO WITH f = fields[i] DO f.type.get_info (info); is_solid := is_solid AND info.is_solid; IF (info.class = Class.Packed) THEN fieldSize := NARROW (f.type, Packed).bits; anyPacked := TRUE; ELSE fieldSize := info.size; fieldAlign := info.alignment; newAlign := MAX (newAlign, fieldAlign); curSize := newSize; newSize := RoundUp (curSize, fieldAlign); is_solid := is_solid AND (curSize = newSize); END; INC (newSize, fieldSize); END; END; IF (anyPacked) THEN (************************************************** (* add a little bit of C compatibility *) IF (Target.PCC_bitfield_type_matters) THEN newAlign := MAX (newAlign, Target.Integer.align); END; ***************************************************) (********* (* find an alignment that avoids scalar word crossings *) IF NOT FindAlignment (newAlign, fields) THEN Restrict ("scalars in packed fields cannot cross word boundaries"); END; ***********) END; curSize := newSize; newSize := RoundUp (curSize, newAlign); is_solid := is_solid AND (curSize = newSize); (* make sure that all copy operations are an integral number of aligned transfers. *) IF (newSize > 0) THEN (* find the largest possible alignment that doesn't change the size of the record... *) VAR z: CARDINAL; BEGIN z := Target.Integer.align; IF (z > newAlign) AND (newSize MOD z = 0) THEN newAlign := z; END; z := Target.Int32.align; IF (z > newAlign) AND (newSize MOD z = 0) THEN newAlign := z; END; z := Target.Int16.align; IF (z > newAlign) AND (newSize MOD z = 0) THEN newAlign := z; END; z := Target.Int8.align; IF (z > newAlign) AND (newSize MOD z = 0) THEN newAlign := z; END; END; END; (************************ (* find an alignment (and hence a size) that's some reasonable number of machine addressable units *) IF newSize <= Target.Int8.size THEN newAlign := MAX (newAlign, Target.Int8.align); ELSIF newSize <= Target.Int16.size THEN newAlign := MAX (newAlign, Target.Int16.align); ELSIF newSize <= Target.Int32.size THEN newAlign := MAX (newAlign, Target.Int32.align); ELSE newAlign := MAX (newAlign, Target.Integer.align); END; **************************) recSize := newSize; recAlign := newAlign; END FieldSizeAndAlignment; PROCEDURERoundUp (size, alignment: INTEGER): INTEGER = BEGIN IF (alignment = 0) THEN RETURN size; ELSE RETURN ((size + alignment - 1) DIV alignment) * alignment; END; END RoundUp;
TYPE PublicRef = T OBJECT brand : TEXT; target : T; traced : BOOLEAN; END; REVEAL Ref = PublicRef BRANDED "M3Type.Ref" OBJECT OVERRIDES get_info := GetRefInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE----------------------------------------------------------------- SET ---GetRefInfo (self: Ref; VAR x: Info) = BEGIN x.size := Target.Address.size; x.min_size := Target.Address.size; x.alignment := Target.Address.align; x.class := Class.Ref; x.is_traced := self.traced; x.is_empty := FALSE; x.is_solid := TRUE; END GetRefInfo;
TYPE PublicSet = T OBJECT domain : T; END; REVEAL Set = PublicSet BRANDED "M3Type.Set" OBJECT OVERRIDES get_info := GetSetInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; END; PROCEDURE------------------------------------------------------------ Subrange ---GetSetInfo (self: Set; VAR x: Info) RAISES {Error} = VAR n: INTEGER; BEGIN IF NOT IsOrdinal (self.domain) THEN Err ("set domain type is not an ordinal type"); END; IF NOT TInt.ToInt (Number (self.domain), n) THEN Err ("set type too large"); END; x.size := RoundUp (n, Target.Integer.size); x.min_size := x.size; x.alignment := MAX (Target.Integer.align, Target.Structure_size_boundary); x.class := Class.Set; x.is_traced := FALSE; x.is_empty := FALSE; x.is_solid := TRUE; END GetSetInfo;
TYPE PublicSubrange = T OBJECT min : Target.Int; max : Target.Int; super : T; END; REVEAL Subrange = PublicSubrange BRANDED "M3Type.Subrange" OBJECT OVERRIDES get_info := GetSubrangeInfo; base := SubrangeBase; is_ordinal := IsAlways; get_bounds := SubrangeBounds; END; PROCEDURE----------------------------------------------------- INTEGER/LONGINT ---GetSubrangeInfo (self: Subrange; VAR x: Info) = VAR rep := FindRangeRep (self); BEGIN x.size := TargetMap.CG_Size[rep]; x.min_size := MinIntegerSize (self.min, self.max); x.alignment := TargetMap.CG_Align[rep]; x.class := Class.Subrange; x.is_traced := FALSE; x.is_empty := TInt.LT (self.max, self.min); x.is_solid := TRUE; END GetSubrangeInfo; PROCEDUREFindRangeRep (self: Subrange): Target.CGType = BEGIN IF TInt.LE (TInt.Zero, self.min) THEN (* look for an unsigned type *) FOR i := FIRST (TargetMap.Word_types) TO LAST (TargetMap.Word_types) DO WITH z = TargetMap.Word_types[i] DO IF TWord.LE (self.max, z.max) THEN RETURN z.cg_type; END; END; END; ELSE (* look for a signed type *) FOR i := FIRST (TargetMap.Integer_types) TO LAST (TargetMap.Integer_types) DO WITH z = TargetMap.Integer_types[i] DO IF TInt.LE (z.min, self.min) AND TInt.LE (self.max, z.max) THEN RETURN z.cg_type; END; END; END; END; IF self.super = Longint THEN RETURN Target.Longint.cg_type; ELSE RETURN Target.Integer.cg_type; END; END FindRangeRep; PROCEDURESubrangeBase (self: Subrange): T = BEGIN RETURN self.super; END SubrangeBase; PROCEDURESubrangeBounds (self: Subrange; VAR min, max: Target.Int): BOOLEAN = BEGIN min := self.min; max := self.max; RETURN TRUE; END SubrangeBounds;
TYPE Precision = {Integer, Longint}; IntType = T BRANDED "M3Type.IntType" OBJECT prec: Precision; OVERRIDES get_info := GetIntInfo; base := SelfBase; is_ordinal := IsAlways; get_bounds := IntBounds; (****************** is_equal := SelfEQ; is_subtype := SelfEQ; ********************) END; PROCEDURE-------------------------------------------------------------- FLOATS ---GetIntInfo (self: IntType; VAR x: Info) = BEGIN CASE self.prec OF | Precision.Integer => x.size := Target.Integer.size; x.min_size := Target.Integer.size; x.alignment := Target.Integer.align; | Precision.Longint => x.size := Target.Longint.size; x.min_size := Target.Longint.size; x.alignment := Target.Longint.align; END; x.class := Class.Integer; x.is_traced := FALSE; x.is_empty := FALSE; x.is_solid := TRUE; END GetIntInfo; PROCEDUREIntBounds (t: T; VAR min, max: Target.Int): BOOLEAN = BEGIN TYPECASE t OF | IntType (z) => CASE z.prec OF | Precision.Integer => min := Target.Integer.min; max := Target.Integer.max; RETURN TRUE; | Precision.Longint => min := Target.Longint.min; max := Target.Longint.max; RETURN TRUE; END; ELSE RETURN FALSE; END; END IntBounds;
TYPE FloatType = T BRANDED "M3Type.FloatType" OBJECT prec: Target.Precision; OVERRIDES get_info := GetFloatInfo; base := SelfBase; is_ordinal := IsNever; get_bounds := NoBounds; (******************** is_equal := SelfEQ; is_subtype := SelfEQ; *********************) END; PROCEDURE------------------------------------------------- shared utility procs ---GetFloatInfo (self: FloatType; VAR x: Info) = TYPE TC = Class; CONST Map = ARRAY Target.Precision OF TC {TC.Real, TC.Longreal, TC.Extended}; BEGIN WITH z = TargetMap.Float_types [self.prec] DO x.size := z.size; x.min_size := z.size; x.alignment := z.align; x.class := Map [self.prec]; x.is_traced := FALSE; x.is_empty := FALSE; x.is_solid := TRUE; END; END GetFloatInfo;
PROCEDURE--------------------------------------------- internal shared methods ---MinIntegerSize (READONLY min, max: Target.Int): INTEGER = VAR z1, z2: INTEGER; n1, n2: BOOLEAN; BEGIN (* compute the minimum size of these elements *) IF TInt.LT (max, min) THEN RETURN 0 END; BitWidth (min, z1, n1); BitWidth (max, z2, n2); z1 := MAX (z1, z2); IF (n1 OR n2) THEN INC (z1); END; RETURN MIN (z1, Target.Integer.size); END MinIntegerSize; PROCEDUREBitWidth (n: Target.Int; VAR width: INTEGER; VAR neg: BOOLEAN) = (*** valid for Target.Longint.min <= n <= Target.Longint.max ***) VAR tmp: Target.Int; BEGIN neg := TInt.LT (n, TInt.Zero); IF (neg) THEN IF NOT TInt.Add (n, TInt.One, tmp) OR NOT TInt.Subtract (TInt.Zero, tmp, n) THEN (* value too large??? *) width := Target.Longint.size; RETURN; END; END; IF NOT powers_done THEN BuildPowerTables () END; width := Target.Longint.size; FOR i := 0 TO LAST (power) DO IF TInt.LE (n, power[i]) THEN width := i; EXIT END; END; END BitWidth; VAR (*CONST*) power : ARRAY [0..BITSIZE (Target.Int)] OF Target.Int; powers_done := FALSE; PROCEDUREBuildPowerTables () = BEGIN power [0] := TInt.One; FOR i := 1 TO LAST (power) DO IF NOT TInt.Add (power[i-1], power[i-1], power[i]) THEN power[i] := Target.Longint.max; END; END; powers_done := TRUE; END BuildPowerTables;
PROCEDURE************************ PROCEDURE SelfEQ (a, b: T): BOOLEAN = BEGIN RETURN (a = b); END SelfEQ; ***********************SelfBase (t: T): T = BEGIN RETURN t; END SelfBase; PROCEDUREIsNever (<*UNUSED*> t: T): BOOLEAN = BEGIN RETURN FALSE; END IsNever; PROCEDUREIsAlways (<*UNUSED*> t: T): BOOLEAN = BEGIN RETURN TRUE; END IsAlways; PROCEDURENoBounds (<*UNUSED*> t: T; VAR min, max: Target.Int): BOOLEAN = BEGIN min := TInt.Zero; max := TInt.MOne; RETURN FALSE; END NoBounds;
PROCEDURE------------------------------------------------------ initialization ---Restrict (msg: TEXT) RAISES {Error} = BEGIN Err ("implementation restriction: " & msg); END Restrict; PROCEDUREErr (msg: TEXT) RAISES {Error} = BEGIN RAISE Error (msg); END Err;
PROCEDUREInitBuiltins () = BEGIN Integer := NEW (IntType, prec := Precision.Integer); Longint := NEW (IntType, prec := Precision.Longint); Real := NEW (FloatType, prec := Target.Precision.Short); LongReal := NEW (FloatType, prec := Target.Precision.Long); Extended := NEW (FloatType, prec := Target.Precision.Extended); Root := NEW (Object, brand := NIL, super := NIL, fields := NIL, methods := NIL, overrides := NIL); UntracedRoot := NEW (Object, brand := NIL, super := NIL, fields := NIL, methods := NIL, overrides := NIL); Refany := NEW (Ref, brand := NIL, target := NIL, traced := TRUE); Address := NEW (Ref, brand := NIL, target := NIL, traced := FALSE); Null := NEW (Ref, brand := NIL, target := NIL, traced := FALSE); Cardinal := NEW (Subrange, min := TInt.Zero, max := Target.Integer.max, super := Integer); Longcard := NEW (Subrange, min := TInt.Zero, max := Target.Longint.max, super := Longint); VAR elts := NEW (REF ARRAY OF M3ID.T, 2); BEGIN elts[0] := M3ID.Add ("FALSE"); elts[1] := M3ID.Add ("TRUE"); Boolean := NEW (Enum, elements := elts); END; Char := NEW (Enum, elements := NEW (REF ARRAY OF M3ID.T, 256)); Mutex := NEW (Opaque, super := Root); Txt := NEW (Opaque, super := Refany); END InitBuiltins; BEGIN InitBuiltins (); END M3Type.