MODULE M3CBackEnd_C  EXPORTS M3CBackEnd, M3CBackEnd_C;

ToDo: all the bootstrap things like FIRST(REAL)

4/25/09: fixed FIRST(REAL) etc. but not sure about what this might break w.r.t. cross-compiling and such things.

Version targeted to C back-end for a variety of machines

IMPORT M3CBackEnd;
IMPORT Fmt, Text, TextRd, TextWr, Rd, Wr, Word, Convert, RdExtras;
IMPORT M3AST_AS, M3AST_SM;

IMPORT M3AST_AS_F, M3AST_SM_F;

IMPORT SeqM3AST_AS_RANGE_EXP, SeqM3AST_AS_Fields;

IMPORT M3CId, M3CLiteral;
IMPORT M3Error, M3Assert, M3CSrcPos;
IMPORT M3CStdProcs, M3CWordProcs;
IMPORT M3CExpValue, M3CTypesMisc, M3ASTNext;
FROM M3CBackEnd_C_cc IMPORT a32, a64, a16, a8, minAlignment, recAlignment,
  arrayAlignment, ptrA, ptrS, realA, realS, longRealA, longRealS, intA, intS,
  longintA, longintS, wideCharA, wideCharS;

IMPORT M3CBackEnd_Int_Integer, M3CBackEnd_Int_Longint;
IMPORT M3CBackEnd_Float_Real, M3CBackEnd_Float_LongReal,
    M3CBackEnd_Float_Extended;

IMPORT Thread;

<*FATAL Thread.Alerted, Wr.Failure, Rd.Failure, Rd.EndOfFile, Convert.Failed *>

CONST
  NilValue = 0;

PROCEDURE OrdAlign(size: INTEGER): INTEGER RAISES {}=
  BEGIN
    IF size = 0 THEN
      RETURN 0
    ELSIF size <= 8 THEN RETURN a8
    ELSIF size <= 16 THEN RETURN a16
    ELSIF size <= 32 THEN RETURN a32
    ELSIF size <= 64 THEN RETURN a64
    ELSE <*ASSERT FALSE*>

    END; (* if *)
  END OrdAlign;

PROCEDURE SetAlign(VAR (*inout*) size: INTEGER; exact: BOOLEAN): INTEGER =
  BEGIN
    IF NOT exact THEN (* represented as arrays of ints *)
      size := AlignTo(size, intS);
    END; (* if *)
    RETURN MAX(intA, recAlignment);
  END SetAlign;

PROCEDURE RegisterProcs() RAISES {}=
  BEGIN
    M3CBackEnd.LiteralValue:= LiteralValue_C;
    M3CBackEnd.ConstructorValue:= ConstructorValue_C;
    M3CBackEnd.ConstructorOriginal:= ConstructorOriginal_C;
    M3CBackEnd.IsOrdinal := IsOrdinal_C;
    M3CBackEnd.Ord:= Ord_C;
    M3CBackEnd.Val:= Val_C;
    M3CBackEnd.ConvertOrdinal := ConvertOrdinal_C;
    M3CBackEnd.BinaryOp:= BinaryOp_C;
    M3CBackEnd.InOp:= InOp_C;
    M3CBackEnd.UnaryOp:= UnaryOp_C;
    M3CBackEnd.StdUnaryOp:= StdUnaryOp_C;
    M3CBackEnd.StdBinaryOp:= StdBinaryOp_C;
    M3CBackEnd.StdUnaryTypeOp:= StdUnaryTypeOp_C;
    M3CBackEnd.WordOp := WordOp_C;
    M3CBackEnd.Compare:= Compare_C;
    M3CBackEnd.LoopholeOK:= LoopholeOK_C;
    M3CBackEnd.BitsOK:= BitsOK_C;
    M3CBackEnd.VarParamOK:= VarParamOK_C;
    M3CBackEnd.BitSizeAndAlign:= BitSizeAndAlign_C;
    M3CBackEnd.ExpValueToText := ExpValueToText_C;
    M3CBackEnd.TextToExpValue := TextToExpValue_C;
  END RegisterProcs;

CONST
  BadBits = -1;

PROCEDURE SizeInBits(ts: M3AST_SM.TYPE_SPEC_UNSET;
    exact := FALSE): INTEGER RAISES {}=
  BEGIN
    IF ts = NIL THEN
      RETURN BadBits
    ELSE
      MayBeExactBitSizeAndAlign(ts, exact);
      RETURN NARROW(ts, M3AST_AS.TYPE_SPEC).sm_bitsize;
    END;
  END SizeInBits;

PROCEDURE BitSizeAndAlign_C(ts: M3AST_AS.TYPE_SPEC) RAISES {}=
  BEGIN
    MayBeExactBitSizeAndAlign(ts);
  END BitSizeAndAlign_C;

PROCEDURE MayBeExactBitSizeAndAlign(ts: M3AST_AS.TYPE_SPEC;
    exact := FALSE) RAISES {}=
  VAR
    array_element, array_index: M3AST_SM.TYPE_SPEC_UNSET;
    size, align: INTEGER;
    isopen: BOOLEAN;
  BEGIN
    size := 0; align := 0;

    TYPECASE ts OF <*NOWARN*>
    | M3AST_AS.Ref_type,
      M3AST_AS.RefAny_type,
      M3AST_AS.Root_type,
      M3AST_AS.Address_type,
      M3AST_AS.Null_type,
      M3AST_AS.Opaque_type,
      M3AST_AS.Procedure_type =>
        size := ptrS;
        align := ptrA;

    | M3AST_AS.Integer_type =>
        size := intS;
        align := intA;

    | M3AST_AS.Longint_type =>
        size := longintS;
        align := longintA;

    | M3AST_AS.WideChar_type =>
        size := wideCharS;
        align := wideCharA;

    | M3AST_AS.Real_type =>
        size := realS;
        align := realA;

    | M3AST_AS.LongReal_type, M3AST_AS.Extended_type =>
        size := longRealS;
        align := longRealA;

    | M3AST_AS.Enumeration_type(t) =>
        size := BitsForInt(t.sm_num_elements-1, exact);
        align := OrdAlign(size);

    | M3AST_AS.Subrange_type(t) =>
        TYPECASE t.sm_base_type_spec OF
        | M3AST_AS.Longint_type =>
          WITH range = t.as_range,
               s1 = NARROW(range.as_exp1.sm_exp_value, Longint_value).sm_value,
               s2 = NARROW(range.as_exp1.sm_exp_value, Longint_value).sm_value
           DO
            IF s1 <= s2 THEN
              IF s1 >= 0L THEN
                size := BitsForLongint(s2, exact);
              ELSE
                IF s2 < 0L THEN s2 := 0L; END;
                size := 1 + MAX(BitsForLongint(-(s1+1L), TRUE),
                                BitsForLongint(s2, TRUE));
                IF NOT exact THEN size := ChooseByteHalfFull(size); END;
              END;
            END; (* if *)
            align := OrdAlign(size);
          END;
        ELSE
          WITH range = t.as_range,
               s1 = NARROW(range.as_exp1.sm_exp_value, Integer_value).sm_value,
               s2 = NARROW(range.as_exp2.sm_exp_value, Integer_value).sm_value
           DO
            IF s1 <= s2 THEN
              IF s1 >= 0 THEN
                size := BitsForInt(s2, exact);
              ELSE
                IF s2 < 0 THEN s2 := 0; END;
                size := 1 + MAX(BitsForInt(-(s1+1), TRUE),
                                BitsForInt(s2, TRUE));
                IF NOT exact THEN size := ChooseByteHalfFull(size); END;
              END;
            END; (* if *)
            align := OrdAlign(size);
          END;
        END;

    | M3AST_AS.Set_type(t) =>
      VAR s1, s2: INTEGER; BEGIN
        GetSetBounds(t, s1, s2);
        IF s1 <= s2 THEN
          size := 1 + s2 - s1;
        END; (* if *)
        align := SetAlign(size, exact);
      END;

    | M3AST_AS.Packed_type(t) =>
        (* the check for legality is done elsewhere *)
        size := NARROW(t.as_exp.sm_exp_value, Integer_value).sm_value;
        align := 1;

    | M3AST_AS.Record_type(t) =>
        FieldsSizeAndAlign(t.as_fields_s, size, align);

    | M3AST_AS.Object_type(object_type) =>
        (* compute in place in case of self-reference *)
        size := ptrS; ts.sm_bitsize := size;
        align :=  ptrA; ts.sm_align := align;
        (* compute the referent size and alignment (for this component
        of the object; i.e. ignore supertypes). *)
        object_type.sm_rf_bitsize := 0;
        object_type.sm_rf_align := 0;
        FieldsSizeAndAlign(object_type.as_fields_s,
            object_type.sm_rf_bitsize, object_type.sm_rf_align);

    | M3AST_AS.Array_type(t) =>
        EVAL M3ASTNext.Array(t, array_element, isopen, array_index);
        WITH elemTS = NARROW(array_element, M3AST_AS.TYPE_SPEC) DO
          align := MAX(elemTS.sm_align, arrayAlignment);
          IF isopen THEN
            (* leave size at 0 *)
          ELSE
            VAR
              low, high: M3AST_SM.Exp_value;
              s1, s2: INTEGER;
            BEGIN
              IF M3CExpValue.GetBounds(array_index, low, high) =
                    M3CBackEnd.NumStatus.Valid THEN
                s1 := NARROW(low, Integer_value).sm_value;
                s2 := NARROW(high, Integer_value).sm_value;
                IF s1 <= s2 THEN
                  size :=
                      AlignTo(elemTS.sm_bitsize, elemTS.sm_align) * (s2-s1+1);
                END;
              END;
            END;
          END;
        END;
    END; (* case *)

    ts.sm_bitsize := size;
    ts.sm_align := align;
  END MayBeExactBitSizeAndAlign;

PROCEDURE FieldsSizeAndAlign(fields: SeqM3AST_AS_Fields.T;
    VAR (*inout*) size, align: INTEGER) RAISES {}=
  VAR
    field_id: M3AST_AS.Field_id;
    iter := M3ASTNext.NewIterField(fields);
  BEGIN
    WHILE M3ASTNext.Field(iter, field_id) DO
      size := AlignTo(size, field_id.sm_type_spec.sm_align);
      INC(size, field_id.sm_type_spec.sm_bitsize);
      align := MAX(align, field_id.sm_type_spec.sm_align);
    END;
    align := MAX(align, recAlignment);
  END FieldsSizeAndAlign;

PROCEDURE LiteralValue_C(lit: M3AST_AS.EXP;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    TYPECASE lit OF <*NOWARN*>
    | M3AST_AS.Char_literal =>
        (* 'x' or '\n' or '\ddd' or '\xDD' or '\XDD'*)
        VAR
          cvi: INTEGER;
          t: TEXT := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.Char_literal).lx_litrep);
        BEGIN
          IF Text.GetChar(t, 1) = '\\' THEN
            (* escape *)
            CASE Text.GetChar(t, 2) OF
            | 'n' => cvi := ORD('\n');
            | 't' => cvi := ORD('\t');
            | 'r' => cvi := ORD('\r');
            | '\'' => cvi := ORD('\'');
            | '\"' => cvi := ORD('\"');
            | 'f' => cvi := ORD('\f');
            | '\\' => cvi := ORD('\\');
            | 'x' , 'X' =>
              cvi := CHV(Text.GetChar(t, 3)) * 16 +
                     CHV(Text.GetChar(t, 4));
            ELSE  (* \ddd *)
              cvi := CHV(Text.GetChar(t, 2)) * 64 +
                     CHV(Text.GetChar(t, 3)) * 8 +
                     CHV(Text.GetChar(t, 4));
            END; (* case *)
          ELSE
            cvi := ORD(Text.GetChar(t, 1));
          END; (* if *)
          er := M3CBackEnd_Int_Integer.New_value(cvi);
        END;

    | M3AST_AS.WideChar_literal =>
        (* 'x' or '\n' or '\dddddd' or '\xDDDD' or '\XDDDD' *)
        VAR
          cvi: INTEGER;
          t: TEXT := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.Char_literal).lx_litrep);
        BEGIN
          IF Text.GetChar(t, 1) = '\\' THEN
            (* escape *)
            CASE Text.GetChar(t, 2) OF
            | 'n' => cvi := ORD('\n');
            | 't' => cvi := ORD('\t');
            | 'r' => cvi := ORD('\r');
            | '\'' => cvi := ORD('\'');
            | '\"' => cvi := ORD('\"');
            | 'f' => cvi := ORD('\f');
            | '\\' => cvi := ORD('\\');
            | 'x' , 'X' =>
              cvi := CHV(Text.GetChar(t, 3)) * 4096 +
                     CHV(Text.GetChar(t, 4)) * 256 +
                     CHV(Text.GetChar(t, 5)) * 16 +
                     CHV(Text.GetChar(t, 6));
            ELSE  (* \ddd *)
              cvi := CHV(Text.GetChar(t, 2)) * 32768 +
                     CHV(Text.GetChar(t, 3)) * 4096 +
                     CHV(Text.GetChar(t, 4)) * 512 +
                     CHV(Text.GetChar(t, 5)) * 64 +
                     CHV(Text.GetChar(t, 6)) * 8 +
                     CHV(Text.GetChar(t, 7));
            END; (* case *)
          ELSE
            cvi := ORD(Text.GetChar(t, 1));
          END; (* if *)
          er := M3CBackEnd_Int_Integer.New_value(cvi);
        END;

    | M3AST_AS.Text_literal =>
        VAR tv := NEW(Text_value);
            t: TEXT := M3CLiteral.ToText(
                NARROW(lit, M3AST_AS.Text_literal).lx_litrep);
        BEGIN
          er := tv;
          tv.sm_value := Text.Sub(t, 1, Text.Length(t) - 2);
        END;

    | M3AST_AS.WideText_literal =>
        VAR tv := NEW(Text_value);
            t: TEXT := M3CLiteral.ToText(
                NARROW(lit, M3AST_AS.Text_literal).lx_litrep);
        BEGIN
          er := tv;
          tv.sm_value := Text.Sub(t, 2, Text.Length(t) - 3);
        END;

    | M3AST_AS.Nil_literal =>
        er := M3CBackEnd_Int_Integer.New_value(NilValue);

    | M3AST_AS.Integer_literal =>
        VAR
          t: TEXT := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.Integer_literal).lx_litrep);
          int: INTEGER;
        BEGIN
          IF NOT TextTo_Integer(t, int) THEN
            RETURN M3CBackEnd.NumStatus.Overflow;
          END;
          er := M3CBackEnd_Int_Integer.New_value(int);
        END;

    | M3AST_AS.Longint_literal =>
        VAR
          t: TEXT := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.Longint_literal).lx_litrep);
          int: LONGINT;
        BEGIN
          IF NOT TextTo_Longint(t, int) THEN
            RETURN M3CBackEnd.NumStatus.Overflow;
          END;
          er := M3CBackEnd_Int_Longint.New_value(int);
        END;

    | M3AST_AS.Real_literal =>
        VAR
	  real: REAL;
	  t := M3CLiteral.ToText(NARROW(lit, M3AST_AS.Real_literal).lx_litrep);
        BEGIN
          IF NOT TextTo_Real(t, real) THEN
            RETURN M3CBackEnd.NumStatus.Overflow;
          END;
          er := M3CBackEnd_Float_Real.New_value(real);
        END;

    | M3AST_AS.LongReal_literal =>
        VAR
	  longReal: LONGREAL;
	  t := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.LongReal_literal).lx_litrep);
        BEGIN
          IF NOT TextTo_LongReal(t, longReal) THEN
            RETURN M3CBackEnd.NumStatus.Overflow;
          END;
          er := M3CBackEnd_Float_LongReal.New_value(longReal)
        END;

    | M3AST_AS.Extended_literal =>
        VAR
	  extended: EXTENDED;
	  t := M3CLiteral.ToText(
              NARROW(lit, M3AST_AS.Extended_literal).lx_litrep);
        BEGIN
          IF NOT TextTo_Extended(t, extended) THEN
            RETURN M3CBackEnd.NumStatus.Overflow;
          END;
          er := M3CBackEnd_Float_Extended.New_value(extended)
        END;

    | M3AST_AS.Exp_used_id, M3AST_AS.Select =>
        (* procedure constants *)
        VAR
          idp, idu: M3AST_AS.Exp_used_id;
          pv := NEW(Proc_value);
        BEGIN
          er := pv;
          IF ISTYPE(lit, M3AST_AS.Select) THEN
            idp := NARROW(lit, M3AST_AS.Select).as_id;
            idu := NARROW(lit, M3AST_AS.Select).as_exp;
          ELSE
            idp := lit; idu := NIL;
          END; (* if *)
          pv.sm_value := M3CId.ToText(idp.vUSED_ID.lx_symrep);
          IF idu # NIL THEN
            pv.sm_value := M3CId.ToText(idu.vUSED_ID.lx_symrep) & Separator &
              pv.sm_value;
          END; (* if *)
        END;
    END; (* case *)
    RETURN M3CBackEnd.NumStatus.Valid;
  END LiteralValue_C;

<*INLINE*> PROCEDURE CHV(ch: CHAR): INTEGER RAISES {}=
  BEGIN
    RETURN ORD(ch) - ORD('0');
  END CHV;

PROCEDURE GetSetBounds(s: M3AST_AS.Set_type; VAR low, high: INTEGER) RAISES {}=
  VAR
    baseType: M3AST_SM.TYPE_SPEC_UNSET;
    l, h: M3AST_SM.Exp_value;
  BEGIN
    M3CTypesMisc.GetTYPE_SPECFromM3TYPE(s.as_type, baseType);
    M3Assert.Check(
        M3CExpValue.GetBounds(baseType, l, h) = M3CBackEnd.NumStatus.Valid);
    low := NARROW(l, Integer_value).sm_value;
    high := NARROW(h, Integer_value).sm_value;
  END GetSetBounds;

PROCEDURE ConstructorValue_C(
    cons: M3AST_AS.Constructor;
    VAR (*out*) er: M3AST_SM.Exp_value)
    : M3CBackEnd.NumStatus
    RAISES {}=
  BEGIN
    TYPECASE M3CTypesMisc.CheckedUnpack(cons.sm_exp_type_spec) OF <*NOWARN*>
    | M3AST_AS.Set_type(setType) =>
        VAR
          cv := NEW(Set_constructor_value);
          s1, s2: INTEGER;
        BEGIN
          GetSetBounds(setType, s1, s2);
          cv.sm_low := s1;
          cv.sm_value := NEW(REF ARRAY OF INTEGER,
              (setType.sm_bitsize + Word.Size - 1) DIV Word.Size);
          FOR i := 0 TO LAST(cv.sm_value^) DO
            cv.sm_value[i] := 0;
          END;
          VAR
            iterActuals := SeqM3AST_AS_RANGE_EXP.NewIter(cons.sm_actual_s);
            actual: M3AST_AS.RANGE_EXP;
            lowBit, highBit: INTEGER;
          BEGIN
            WHILE SeqM3AST_AS_RANGE_EXP.Next(iterActuals, actual) DO
              TYPECASE actual OF <*NOWARN*>
              | M3AST_AS.Range_EXP(rExp) =>
                  lowBit := NARROW(
                      rExp.as_exp.sm_exp_value, Integer_value).sm_value;
                  highBit := lowBit;
              | M3AST_AS.Range(range) =>
                  lowBit := NARROW(
                      range.as_exp1.sm_exp_value, Integer_value).sm_value;
                  highBit := NARROW(
                      range.as_exp2.sm_exp_value, Integer_value).sm_value;
              END;
              DEC(lowBit, s1);
              DEC(highBit, s1);
              FOR setbit := lowBit TO highBit DO
                WITH w = cv.sm_value[setbit DIV Word.Size] DO
                  w := Word.Or(w, Word.Shift(1, setbit MOD Word.Size));
                END;
              END;
            END;
          END;
          er := cv;
        END;
    | M3AST_AS.Record_type, M3AST_AS.Array_type =>
        VAR
          cv := NEW(Array_or_record_constructor_value);
        BEGIN
          cv.sm_constructor := cons;
          er := cv;
        END;
    END;
    RETURN M3CBackEnd.NumStatus.Valid;
  END ConstructorValue_C;

PROCEDURE ConstructorOriginal_C(
    e: M3AST_SM.Exp_value)
    : M3AST_AS.Constructor
    RAISES {}=
  BEGIN
    TYPECASE e OF <*NOWARN*>
    | Array_or_record_constructor_value(cv) =>
        RETURN cv.sm_constructor;
    END; (* typecase *)
  END ConstructorOriginal_C;

PROCEDURE IsOrdinal_C(e: M3AST_SM.Exp_value): BOOLEAN RAISES {}=
  BEGIN
    RETURN e # NIL AND (ISTYPE(e, Integer_value) OR ISTYPE(e, Longint_value));
  END IsOrdinal_C;

PROCEDURE Val_C(n: INTEGER;
                ts: M3AST_SM.TYPE_SPEC_UNSET;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    (* ORD(n) = n for all types *)
    TYPECASE ts OF
    | M3AST_AS.Longint_type =>
      er := M3CBackEnd_Int_Longint.New_value(VAL(n, LONGINT));
      RETURN M3CBackEnd.NumStatus.Valid;
    | M3AST_AS.Subrange_type(subrange) =>
      RETURN Val_C(n, subrange.sm_base_type_spec, er);
    ELSE
      er := M3CBackEnd_Int_Integer.New_value(VAL(n, INTEGER));
      RETURN M3CBackEnd.NumStatus.Valid;
    END;
  END Val_C;

PROCEDURE Ord_C(
    e: M3AST_SM.Exp_value;
    VAR (*out*) i: INTEGER)
    : M3CBackEnd.NumStatus
    RAISES {}=
  BEGIN
    TYPECASE e OF <*NOWARN*>
    | Integer_value(iv) =>
        i := iv.sm_value;
        RETURN M3CBackEnd.NumStatus.Valid;
    | Longint_value(iv) =>
        IF iv.sm_value < VAL(FIRST(INTEGER), LONGINT) THEN
          RETURN M3CBackEnd.NumStatus.Overflow;
        END;
        IF iv.sm_value > VAL(LAST(INTEGER), LONGINT) THEN
          RETURN M3CBackEnd.NumStatus.Overflow;
        END;
        i := VAL(iv.sm_value, INTEGER);
        RETURN M3CBackEnd.NumStatus.Valid;
    END;
  END Ord_C;

PROCEDURE ConvertOrdinal_C(
    e: M3AST_SM.Exp_value;
    ts: M3AST_AS.TYPE_SPEC;
    VAR (* out *) er: M3AST_SM.Exp_value)
    : M3CBackEnd.NumStatus
    RAISES {}=
  BEGIN
    TYPECASE ts OF
    | M3AST_AS.Longint_type =>
      TYPECASE e OF <*NOWARN*>
      | Integer_value(iv) =>
        er := M3CBackEnd_Int_Longint.New_value(VAL(iv.sm_value, LONGINT));
      | Longint_value => er := e;
      END;
    | M3AST_AS.Subrange_type(subrange) =>
      RETURN ConvertOrdinal_C(e, subrange.sm_base_type_spec, er);
    ELSE
      TYPECASE e OF <*NOWARN*>
      | Integer_value => er := e;
      | Longint_value(iv) =>
        IF iv.sm_value < VAL(FIRST(INTEGER), LONGINT) THEN
          RETURN M3CBackEnd.NumStatus.Overflow;
        END;
        IF iv.sm_value > VAL(LAST(INTEGER), LONGINT) THEN
          RETURN M3CBackEnd.NumStatus.Overflow;
        END;
        er := M3CBackEnd_Int_Integer.New_value(VAL(iv.sm_value, INTEGER));
      END;
    END;
    RETURN M3CBackEnd.NumStatus.Valid;
  END ConvertOrdinal_C;

PROCEDURE BinaryOp_C(op: M3AST_AS.BINARY; e1, e2: M3AST_SM.Exp_value;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    (* Compatibility check *)
    IF TYPECODE(e1) # TYPECODE(e2) THEN
      RETURN M3CBackEnd.NumStatus.Unknown;
    END;
    (* Now the real work, computing values *)
    TYPECASE e2 OF
    | Integer_value(iv2) =>
        RETURN M3CBackEnd_Int_Integer.BinaryOp(op, NARROW(e1, Integer_value),
                                               iv2, er);

    | Longint_value(liv2) =>
        RETURN M3CBackEnd_Int_Longint.BinaryOp(op, NARROW(e1, Longint_value),
                                               liv2, er);

    | Text_value(textValue2) =>
        VAR
          tv := NEW(Text_value);
        BEGIN
          IF ISTYPE(op, M3AST_AS.Textcat) THEN
            er := tv;
            tv.sm_value :=
                NARROW(e1, Text_value).sm_value & textValue2.sm_value;
          ELSE
            RETURN M3CBackEnd.NumStatus.Unknown;
          END;
        END;

    | Real_value(rv2) =>
        RETURN M3CBackEnd_Float_Real.BinaryOp(op,
                                              NARROW(e1, Real_value), rv2, er);

    | LongReal_value(lrv2) =>
        RETURN M3CBackEnd_Float_LongReal.BinaryOp(op,
            NARROW(e1, LongReal_value), lrv2, er);

    | Extended_value(ev2) =>
        RETURN M3CBackEnd_Float_Extended.BinaryOp(op,
            NARROW(e1, Extended_value), ev2, er);

    | Set_constructor_value(c2) =>
        VAR
          c1 := NARROW(e1, Set_constructor_value);
        BEGIN
          IF NUMBER(c1.sm_value^) # NUMBER(c2.sm_value^) THEN
            RETURN M3CBackEnd.NumStatus.Unknown;
          END;
          TYPECASE op OF <*NOWARN*>
          | M3AST_AS.Plus,
            M3AST_AS.Minus,
            M3AST_AS.Times,
            M3AST_AS.Rdiv =>
              (* All return set as result *)
              VAR
                cv := NEW(Set_constructor_value);
              BEGIN
                cv.sm_value := NEW(REF ARRAY OF INTEGER, NUMBER(c1.sm_value^));
                er := cv;
                FOR i := 0 TO LAST(c1.sm_value^) DO
                  WITH w = cv.sm_value[i] DO
                    VAR
                      w1 := c1.sm_value[i];
                      w2 := c2.sm_value[i];
                    BEGIN
                      TYPECASE op OF <*NOWARN*>
                      | M3AST_AS.Plus =>
                          w := Word.Or(w1, w2);
                      | M3AST_AS.Minus =>
                         w := Word.And(w1, Word.Not(w2));
                      | M3AST_AS.Times =>
                          w := Word.And(w1, w2);
                      | M3AST_AS.Rdiv =>
                          w := Word.Xor(w1, w2);
                      END; (* case *)
                    END;
                  END; (* with *)
                END; (* for *)
              END;

          | M3AST_AS.Eq, M3AST_AS.Ne,
            M3AST_AS.Le, M3AST_AS.Ge,
            M3AST_AS.Lt, M3AST_AS.Gt =>
              (* All return booleans. The following is not very efficient but
               who cares? It won't get executed very often. *)
              VAR
                result: BOOLEAN;
              BEGIN
                IF Compare(c1, c2) = 0 THEN
                  (* Equal *)
                  TYPECASE op OF <*NOWARN*>
                  | M3AST_AS.Eq, M3AST_AS.Le, M3AST_AS.Ge =>
                      result := TRUE;
                  | M3AST_AS.Ne, M3AST_AS.Lt, M3AST_AS.Gt =>
                      result := FALSE;
                  END;
                ELSE
                  (* Not equal *)
                  TYPECASE op OF
                  | M3AST_AS.Eq =>
                      result := FALSE;
                  | M3AST_AS.Ne =>
                      result := TRUE;
                  ELSE
                    IF ISTYPE(op, M3AST_AS.Le) OR
		       ISTYPE(op, M3AST_AS.Lt) THEN
                      VAR
                        temp := c1;
                      BEGIN
                        c1 := c2; c2 := temp;
                      END;
                    END;
                    result := TRUE;
                    FOR i := 0 TO LAST(c1.sm_value^) DO
                      VAR
                        elem1 := c1.sm_value[i];
                      BEGIN
                        IF elem1 # Word.Or(elem1, c2.sm_value[i]) THEN
                          result := FALSE;
                          EXIT;
                        END;
                      END;
                    END;
                  END;
                END;
                er := M3CBackEnd_Int_Integer.New_value(ORD(result));
              END;
          END; (* case *)
        END; (* begin *)

    ELSE
      RETURN NotImplemented();
    END; (* case *)

    RETURN M3CBackEnd.NumStatus.Valid;
  END BinaryOp_C;

PROCEDURE InOp_C(e1, e2: M3AST_SM.Exp_value;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  VAR
    int := NARROW(e1, Integer_value).sm_value;
    set := NARROW(e2, Set_constructor_value);
    bool: BOOLEAN;
  BEGIN
    WITH i = int - set.sm_low, s = set.sm_value DO
      bool := Word.Extract(s[i DIV Word.Size], i MOD Word.Size, 1) # 0;
    END;
    er := M3CBackEnd_Int_Integer.New_value(ORD(bool));
    RETURN M3CBackEnd.NumStatus.Valid;
  END InOp_C;

PROCEDURE UnaryOp_C(op: M3AST_AS.UNARY; e: M3AST_SM.Exp_value;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    TYPECASE e OF
    | Integer_value(iv) =>
        RETURN M3CBackEnd_Int_Integer.UnaryOp(op, iv, er);

    | Longint_value(liv) =>
        RETURN M3CBackEnd_Int_Longint.UnaryOp(op, liv, er);

    | Real_value(rv) =>
        RETURN M3CBackEnd_Float_Real.UnaryOp(op, rv, er);

    | LongReal_value(lrv) =>
        RETURN M3CBackEnd_Float_LongReal.UnaryOp(op, lrv, er);

    | Extended_value(ev) =>
        RETURN M3CBackEnd_Float_Extended.UnaryOp(op, ev, er);

    ELSE
      RETURN M3CBackEnd.NumStatus.Unknown;
    END; (* case *)
  END UnaryOp_C;

PROCEDURE StdUnaryOp_C(f: M3CStdProcs.Func;
    e: M3AST_SM.Exp_value;
    VAR (*out*) er: M3AST_SM.Exp_value;
    it: M3AST_AS.INT_TYPE := NIL;
    ft: M3AST_AS.FLOAT_TYPE := NIL):
  M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    TYPECASE e OF
    | Integer_value(iv) =>
        RETURN M3CBackEnd_Int_Integer.StdUnaryOp(f, iv, er, it, ft);

    | Longint_value(liv) =>
        RETURN M3CBackEnd_Int_Longint.StdUnaryOp(f, liv, er, it, ft);

    | Real_value(rv) =>
        RETURN M3CBackEnd_Float_Real.StdUnaryOp(f, rv, er, it, ft);

    | LongReal_value(lrv) =>
        RETURN M3CBackEnd_Float_LongReal.StdUnaryOp(f, lrv, er, it, ft);

    | Extended_value(ev) =>
        RETURN M3CBackEnd_Float_Extended.StdUnaryOp(f, ev, er, it, ft);
    ELSE
      RETURN NotImplemented();
    END; (* case *)
  END StdUnaryOp_C;

PROCEDURE StdBinaryOp_C(f: M3CStdProcs.Func;
    e1, e2: M3AST_SM.Exp_value;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    IF TYPECODE(e1) # TYPECODE(e2) THEN RETURN
      M3CBackEnd.NumStatus.Unknown;
    END;
    TYPECASE e1 OF
    | Integer_value(iv1) =>
        RETURN M3CBackEnd_Int_Integer.StdBinaryOp(f, iv1,
            NARROW(e2, Integer_value), er);

    | Longint_value(liv1) =>
        RETURN M3CBackEnd_Int_Longint.StdBinaryOp(f, liv1,
            NARROW(e2, Longint_value), er);

    | Real_value(rv1) =>
        RETURN M3CBackEnd_Float_Real.StdBinaryOp(f, rv1,
            NARROW(e2, Real_value), er);

    | LongReal_value(lrv1) =>
        RETURN M3CBackEnd_Float_LongReal.StdBinaryOp(f, lrv1,
            NARROW(e2, LongReal_value), er);

    | Extended_value(ev1) =>
        RETURN M3CBackEnd_Float_Extended.StdBinaryOp(f, ev1,
            NARROW(e2, Extended_value), er);

    ELSE
      RETURN NotImplemented();
    END; (* case *)
  END StdBinaryOp_C;

PROCEDURE StdUnaryTypeOp_C(
    pf: M3CStdProcs.Func;
    ts: M3AST_SM.TYPE_SPEC_UNSET;
    VAR (*out*) er: M3AST_SM.Exp_value): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    CASE pf OF
    | M3CStdProcs.T.BitSize =>
        er := M3CBackEnd_Int_Integer.New_value(SizeInBits(ts));
    | M3CStdProcs.T.ByteSize,
      M3CStdProcs.T.AdrSize =>
        er := M3CBackEnd_Int_Integer.New_value(RoundToByte(SizeInBits(ts)));
    | M3CStdProcs.T.First =>
        TYPECASE ts OF <*NOWARN*>
        | M3AST_AS.Integer_type =>
            er := M3CBackEnd_Int_Integer.New_value(FIRST(INTEGER));
        | M3AST_AS.Longint_type =>
            er := M3CBackEnd_Int_Longint.New_value(FIRST(LONGINT));
        | M3AST_AS.WideChar_type =>
            er := M3CBackEnd_Int_Integer.New_value(ORD(FIRST(WIDECHAR)));
        | M3AST_AS.Real_type =>
          er := M3CBackEnd_Float_Real.New_value(FIRST(REAL))
        | M3AST_AS.LongReal_type =>
          er := M3CBackEnd_Float_LongReal.New_value(FIRST(LONGREAL))
        | M3AST_AS.Extended_type =>
          er := M3CBackEnd_Float_Extended.New_value(FIRST(EXTENDED))
        END; (* typecase *)
    | M3CStdProcs.T.Last =>
        TYPECASE ts OF <*NOWARN*>
        | M3AST_AS.Integer_type =>
            er := M3CBackEnd_Int_Integer.New_value(LAST(INTEGER));
        | M3AST_AS.Longint_type =>
            er := M3CBackEnd_Int_Longint.New_value(LAST(LONGINT));
        | M3AST_AS.WideChar_type =>
            er := M3CBackEnd_Int_Integer.New_value(ORD(LAST(WIDECHAR)));
        | M3AST_AS.Real_type =>
          er := M3CBackEnd_Float_Real.New_value(LAST(REAL))
        | M3AST_AS.LongReal_type =>
          er := M3CBackEnd_Float_LongReal.New_value(LAST(LONGREAL))
        | M3AST_AS.Extended_type =>
          er := M3CBackEnd_Float_Extended.New_value(LAST(EXTENDED))
        END; (* typecase *)
    ELSE
      RETURN NotImplemented();
    END; (* case *)
    RETURN M3CBackEnd.NumStatus.Valid;
  END StdUnaryTypeOp_C;

PROCEDURE RoundToByte(n: INTEGER): INTEGER RAISES {}=
  CONST
    BitsInByte = 8;
  VAR er: INTEGER;
  BEGIN
    er := n DIV BitsInByte;
    IF (n MOD BitsInByte) # 0 THEN
      INC(er);
    END; (* if *)
    RETURN er;
  END RoundToByte;

PROCEDURE WordOp_C(
    w: M3CWordProcs.T;
    READONLY args: ARRAY OF M3AST_SM.Exp_value;
    VAR (* out *) er: M3AST_SM.Exp_value)
    : M3CBackEnd.NumStatus
    RAISES {}=
  BEGIN
    TYPECASE args[0] OF
    | Integer_value =>
      RETURN M3CBackEnd_Int_Integer.WordOp(w, args, er);
    | Longint_value =>
      RETURN M3CBackEnd_Int_Longint.WordOp(w, args, er);
    ELSE
      RETURN NotImplemented();
    END;
  END WordOp_C;

PROCEDURE LoopholeOK_C(<*UNUSED*> e: M3AST_AS.EXP;
    <*UNUSED*> ts: M3AST_AS.TYPE_SPEC): BOOLEAN RAISES {}=
  BEGIN
    RETURN TRUE; (* no extra prohibitions *)
  END LoopholeOK_C;

PROCEDURE AlignTo(size, align: CARDINAL): INTEGER RAISES {}=
  VAR
    rem: CARDINAL;
  BEGIN
    IF align = 0 THEN RETURN size END;
    rem := size MOD align;
    IF rem = 0 THEN
      RETURN size
    ELSE
      RETURN size - rem + align;
    END; (* if *)
  END AlignTo;

PROCEDURE BitsForInt(n: INTEGER; exact := FALSE): CARDINAL RAISES {}=
  VAR i, c: CARDINAL;
  BEGIN
    IF n <= 0 THEN RETURN 0 END;
    i := 0;
    c := n;
    WHILE c # 0 DO
      INC(i); c := c DIV 2;
    END; (* while *)
    IF NOT exact THEN
      i := ChooseByteHalfFull(i);
    END;
    RETURN i;
  END BitsForInt;

PROCEDURE BitsForLongint(n: LONGINT; exact := FALSE): CARDINAL RAISES {}=
  VAR i: CARDINAL;
  BEGIN
    IF n <= 0L THEN RETURN 0 END;
    i := 0;
    WHILE n # 0L DO
      INC(i); n := n DIV 2L;
    END; (* while *)
    IF NOT exact THEN
      i := ChooseByteHalfFull(i);
    END;
    RETURN i;
  END BitsForLongint;

PROCEDURE ChooseByteHalfFull(i: INTEGER): INTEGER=
  BEGIN
    IF i <= 8 THEN i := 8
    ELSIF i <= 16 THEN i := 16;
    ELSIF i <= 32 THEN i := 32;
    ELSIF i <= 64 THEN i := 64;
    ELSE <*ASSERT FALSE*>
    END; (* if *)
    RETURN i;
  END ChooseByteHalfFull;

PROCEDURE BitsOK_C(e: M3AST_AS.EXP;
    ts: M3AST_AS.TYPE_SPEC): BOOLEAN RAISES {}=
  VAR tts: M3AST_SM.TYPE_SPEC_UNSET;
  BEGIN
    M3Assert.Check(ISTYPE(e.sm_exp_value, Integer_value));
    tts := ts;
    RETURN SizeInBits(tts, exact := TRUE) <=
           NARROW(e.sm_exp_value, Integer_value).sm_value;
  END BitsOK_C;

PROCEDURE VarParamOK_C(ts: M3AST_AS.TYPE_SPEC): BOOLEAN RAISES {}=
  BEGIN
    RETURN ts.sm_align MOD minAlignment = 0;
  END VarParamOK_C;

PROCEDURE Compare_C(e1, e2: M3AST_SM.Exp_value): INTEGER RAISES {}=
  BEGIN
    TYPECASE e1 OF
    | Integer_value(eiv1) =>
        TYPECASE e2 OF
        | Integer_value(eiv2) =>
            IF eiv1.sm_value = eiv2.sm_value THEN
              RETURN 0
            ELSIF eiv1.sm_value < eiv2.sm_value THEN
              RETURN -1
            ELSE
              RETURN 1
            END; (* if *)
        ELSE
          RETURN 1;
        END;

    | Longint_value(eiv1) =>
        TYPECASE e2 OF
        | Longint_value(eiv2) =>
            IF eiv1.sm_value = eiv2.sm_value THEN
              RETURN 0
            ELSIF eiv1.sm_value < eiv2.sm_value THEN
              RETURN -1
            ELSE
              RETURN 1
            END; (* if *)
        ELSE
          RETURN 1;
        END;

    | Set_constructor_value(cv1) =>
        TYPECASE e2 OF
        | Set_constructor_value(cv2) =>
            WITH s1 = cv1.sm_value, s2 = cv2.sm_value DO
              IF NUMBER(cv1.sm_value^) = NUMBER(cv2.sm_value^) THEN
                FOR i := 0 TO LAST(cv1.sm_value^) DO
                  IF s1[i] # s2[i] THEN RETURN 1 END;
                END;
              ELSE
                 RETURN 1;
              END;
              RETURN 0;
            END;
        ELSE
          RETURN 1;
        END;

    | Text_value(tv1) =>
        TYPECASE e2 OF
        | Text_value(tv2) =>
            RETURN Text.Compare(tv1.sm_value, tv2.sm_value);
        ELSE
          RETURN 1;
        END;

    | Proc_value(pv1) =>
        TYPECASE e2 OF
        | Proc_value(pv2) =>
            RETURN Text.Compare(pv1.sm_value, pv2.sm_value);
        ELSE
          RETURN 1;
        END;

    | Real_value(rv1) =>
        TYPECASE e2 OF
        | Real_value(rv2) =>
            IF rv1.sm_value = rv2.sm_value THEN RETURN 0
            ELSIF rv1.sm_value < rv2.sm_value THEN RETURN -1
            ELSE  RETURN 1
            END; (* if *)
        ELSE RETURN 1;
        END;

    | LongReal_value(rv1) =>
        TYPECASE e2 OF
        | LongReal_value(rv2) =>
            IF rv1.sm_value = rv2.sm_value THEN RETURN 0
            ELSIF rv1.sm_value < rv2.sm_value THEN RETURN -1
            ELSE RETURN 1
            END; (* if *)
        ELSE RETURN 1;
        END;

    | Extended_value(rv1) =>
        TYPECASE e2 OF
        | Extended_value(rv2) =>
            IF rv1.sm_value = rv2.sm_value THEN RETURN 0
            ELSIF rv1.sm_value < rv2.sm_value THEN RETURN -1
            ELSE RETURN 1
            END; (* if *)
        ELSE RETURN 1;
        END;

    ELSE
      EVAL NotImplemented();
      RETURN 0;
    END; (* case *)
  END Compare_C;

PROCEDURE NotImplemented(): M3CBackEnd.NumStatus RAISES {}=
  BEGIN
    M3Error.ReportAtPos(M3CSrcPos.Null, "back-end facility not implemented");
    RETURN M3CBackEnd.NumStatus.Unknown;
  END NotImplemented;

CONST
  SetCh = 's';
  LongRealCh = 'l';  LongRealText = "l";
  RealCh = 'r';      RealText = "r";
  TextCh = 't';      TextText = "t";
  ProcCh = 'p';      ProcText = "p";
  LongintCh = 'i';   LongintText = "i";
  (* Integer values, hopefully the most common, are just hex numbers *)

PROCEDURE ExpValueToText_C(e: M3AST_SM.Exp_value): TEXT RAISES {}=
  BEGIN
    TYPECASE e OF <*NOWARN*>
    | Integer_value(intValue) =>
        RETURN Fmt.Int(intValue.sm_value, 16);
    | Longint_value(intValue) =>
        RETURN LongintText & Fmt.LongInt(intValue.sm_value, 16);
    | Set_constructor_value(setValue) =>
        VAR
          s := TextWr.New();
          val := setValue.sm_value;
          result: TEXT;
        BEGIN
          Wr.PutChar(s, SetCh);
          Wr.PutText(s, Fmt.F("%s %s",
              Fmt.Int(setValue.sm_low, 16),
              Fmt.Int(NUMBER(val^), 16)));
          FOR i := 0 TO LAST(val^) DO
            Wr.PutText(s, Fmt.F(" %s", Fmt.Int(val[i], 16)));
          END;
          result := TextWr.ToText(s);
          Wr.Close(s);
          RETURN result;
        END;
    | LongReal_value(longValue) =>
        RETURN LongRealText & Fmt.LongReal(longValue.sm_value);
    | Real_value(realValue) =>
        RETURN RealText & Fmt.Real(realValue.sm_value);
    | Proc_value(procValue) =>
        RETURN ProcText & procValue.sm_value;
    | Text_value(textValue) =>
        RETURN TextText & textValue.sm_value;
    END;
  END ExpValueToText_C;

EXCEPTION
  Fatal;
<*FATAL Fatal*>

PROCEDURE TextToExpValue_C(t: TEXT): M3AST_SM.Exp_value RAISES {}=
  VAR
    length := Text.Length(t);
  BEGIN
    CASE Text.GetChar(t, 0) OF
    | SetCh =>
        RETURN SetTextToExpValue(t);
    | LongRealCh =>
        VAR
	  new := NEW(LongReal_value);
        BEGIN
          IF NOT TextTo_LongReal(t, new.sm_value) THEN RAISE Fatal END;
          RETURN new;
        END;
    | RealCh =>
        VAR
	  new := NEW(Real_value);
        BEGIN
          IF NOT TextTo_Real(t, new.sm_value) THEN RAISE Fatal END;
          RETURN new;
        END;
    | ProcCh =>
        RETURN NEW(Proc_value, sm_value := Text.Sub(t, 1, length - 1));
    | TextCh =>
        RETURN NEW(Text_value, sm_value := Text.Sub(t, 1, length - 1));
    | LongintCh =>
      VAR new := NEW(Longint_value);
      BEGIN
        IF NOT TextTo_Longint(t, new.sm_value, 16) THEN RAISE Fatal END;
        RETURN new;
      END;
    ELSE
      VAR
        new := NEW(Integer_value);
      BEGIN
        IF NOT TextTo_Integer(t, new.sm_value, 16) THEN RAISE Fatal END;
        RETURN new;
      END;
    END
  END TextToExpValue_C;

PROCEDURE SetTextToExpValue(t: TEXT): Set_constructor_value RAISES {}=
  VAR
    new := NEW(Set_constructor_value);
    s := TextRd.New(t);
  BEGIN
    EVAL(Rd.GetChar(s));
    new.sm_low := GetInt(s, 16);
    new.sm_value := NEW(REF ARRAY OF INTEGER, GetInt(s, 16));
    FOR i := 0 TO LAST(new.sm_value^) DO
      new.sm_value[i] := GetInt(s, 16);
    END;
    Rd.Close(s);
    RETURN new;
  END SetTextToExpValue;

PROCEDURE GetInt(s: Rd.T; base: CARDINAL): INTEGER=
  VAR t := RdExtras.GetText(s); result: INTEGER;
  BEGIN
    EVAL TextTo_Integer(t, result, base);
    RETURN result;
  END GetInt;

PROCEDURE TextTo_Integer(t: Text.T;
    VAR i: INTEGER;
    <*UNUSED*> base: Fmt.Base := 10)
    : BOOLEAN=
  VAR used: INTEGER; len: INTEGER;  buf: ARRAY [0..65] OF CHAR;
  BEGIN
    M3Assert.Check(t # NIL);
    len := Text.Length(t);
    M3Assert.Check(len <= NUMBER(buf));
    Text.SetChars(buf, t);
    IF len>2 AND buf[2] = '_' OR
       len>1 AND buf[1] = '_' THEN
      i := Convert.ToUnsigned(SUBARRAY(buf, 0, len), used);
    ELSE
      i := Convert.ToInt(SUBARRAY(buf, 0, len), used);
    END;
    RETURN used = len;
  END TextTo_Integer;

PROCEDURE TextTo_Longint(t: Text.T;
    VAR i: LONGINT;
    <*UNUSED*> base: Fmt.Base := 10)
    : BOOLEAN=
  VAR used: INTEGER; len: INTEGER;  buf: ARRAY [0..66] OF CHAR;
  BEGIN
    M3Assert.Check(t # NIL);
    len := Text.Length(t);
    M3Assert.Check(len <= NUMBER(buf));
    Text.SetChars(buf, t);
    IF len>2 AND buf[2] = '_' OR
       len>1 AND buf[1] = '_' THEN
      i := Convert.ToLongUnsigned(SUBARRAY(buf, 0, len), used);
    ELSE
      i := Convert.ToLongInt(SUBARRAY(buf, 0, len), used);
    END;
    INC (used , ORD(buf[len-1] = 'L' OR buf[len-1] = 'l'));
    RETURN used = len;
  END TextTo_Longint;

PROCEDURE TextTo_Real(t: Text.T; VAR real: REAL): BOOLEAN=
  VAR used: INTEGER;  buf: ARRAY [0..63] OF CHAR;  len := Text.Length(t);
  BEGIN
    M3Assert.Check(len <= NUMBER(buf));
    Text.SetChars(buf, t);
    real := Convert.ToFloat(SUBARRAY(buf, 0, len), used);
    RETURN used = len;
  END TextTo_Real;

PROCEDURE TextTo_LongReal(t: Text.T; VAR long: LONGREAL): BOOLEAN=
  VAR used: INTEGER;  buf: ARRAY [0..63] OF CHAR;  len := Text.Length(t);
  BEGIN
    M3Assert.Check(len <= NUMBER(buf));
    Text.SetChars(buf, t);
    long := Convert.ToLongFloat(SUBARRAY(buf, 0, len), used);
    RETURN used = len;
  END TextTo_LongReal;

PROCEDURE TextTo_Extended(t: Text.T; VAR extended: EXTENDED): BOOLEAN=
  VAR used: INTEGER;  buf: ARRAY [0..63] OF CHAR;  len := Text.Length(t);
  BEGIN
    M3Assert.Check(len <= NUMBER(buf));
    Text.SetChars(buf, t);
    extended := Convert.ToExtended(SUBARRAY(buf, 0, len), used);
    RETURN used = len;
  END TextTo_Extended;

BEGIN
  RegisterProcs();
END M3CBackEnd_C.