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#LEX: LEXICAL ANALYZER MODULE FOR IMP COMPILER#
TWOSEG;

BHEAD,FINAM ARE COMMON;
C IS REGISTER,RESERVED,SCRATCH;


SUBR LEXIN() IS (
 CHAN_OPENIN();
 CHAN=0 => RETURN -1;
 LINIT=0=>(LINIT_1;
	LINE_FALLOT('LEXL',20); LLINE_90;
	TOKE_FALLOT('LEXT',20); LTOKE_90;
	PC_QC_BYTEP FREE(LINE)<7,36>;
	K0_BYTEP FREE(TOKE)<7,36>);
 FREES(LINE,0);
 PCT_0);

SUBR LEX(S) IS (
     C_CSV; K_K0; ITOKE_0;
 T0: SKIP=0 => NEXTCHAR(); SKIP_0;
     ISANM=0 => GO TO T2;
 T1: <+K>_C; NEXTCHAR();
     ISANM => GO TO T1;
     SKIP_-1; GO TO LX;
 T2: C LE 040B=>GO TO T0;
     C=043B => (T3: NEXTCHAR();
                C NE 043B => GO TO T3;
                GO TO T0);
     C=047B => (T4: <+K>_C; NEXTCHAR();
                C NE 047B => GO TO T4;
		NEXTCHAR(); C=047B=>GO TO T4;
		SKIP_-1;
                GO TO LX);
     C=041B => (T5: NEXTCHAR();
                C NE 041B => (<+K>_C; GO TO T5);
                GO TO LX);
     <+K>_C;
 LX: <+K>_0 FOR I FROM 4;
     CSV_C;
     S_DIR(FREE(TOKE)); IC);

SUBR LEXSAV() IS (PC0_PC; IC0_IC; SKIP0_SKIP; CSV0_CSV; ISANM0_ISANM; SKIP_0);

SUBR LEXRES() IS (PC_PC0; IC_IC0; SKIP_SKIP0; CSV_CSV0; ISANM_ISANM0);

SUBR NEXTCHAR() IS (
 (ITOKE_ITOKE+1) GE LTOKE=>(
	TOKE_FALLOT(OTOKE_TOKE,(10+LTOKE_LTOKE+50)/5);
	K_K-OTOKE_OTOKE-TOKE; K0_K0-OTOKE);
 NEXT: C_<+PC>; IC_IC+1;
 C=0 => (PC_QC; OPCT_PCT;
	 ILINE_0;
         GCHRS: (BHEAD[2]_BHEAD[2]-1) LE 0 => INPUT(CHAN) =>
                            ERROR(0,'PREMATURE END OF INPUT FILE');
	 (ILINE_ILINE+1) GE LLINE=>(
		LINE_FALLOT(OTOKE_LINE,(10+LLINE_LLINE+50)/5);
		PC_PC-OTOKE_OTOKE-LINE; QC_QC-OTOKE);
         C_<+BHEAD[1]>;
	 C NE 12B=>(C=><+PC>_C;
	         C='(' RS 29 => PCT_PCT+1;
	         C=')' RS 29 => PCT_PCT-1;
		GO TO GCHRS);
         <+PC>_0; PC_QC; IC_TFL_0;
         PLINE(FREE(LINE),OPCT); C_12B);
 #ISANM IS MADE NON-ZERO FOR ALPHA-NUMERIC CHARS#
 ISANM_(1 LS 35) AND ISTAB[C RS 5] LS 37B AND C);

ISTAB: DATA(0,3776000B,377777777000B,377777777000B);

SUBR PLINE1(OL) IS (TFL=0=>(TFL_-1; RC_QC; J_0;
 WHILE (I_<+RC>) DO (
	(J_J+1)=OL=>OUTCHR(12B); OUTCHR(I));
 OUTCHR(12B)));

SUBR PLINE(BF,PCT) IS (
 FINAM[5] AND 4000B => PRINT IGR 3,PCT,STG 0,' ',BF,/;
 FINAM[5] AND 100000000B => MSG(BF));

SUBR GETTY(BF) IS (OUTSTR('*');
                   Q_BYTEP BF<7,36>;
                   PL: C_INCHWL(0);
                       C=041B => C_134B;
                       C GE 040B => <+Q>_C;
                       C NE 015B => GO TO PL;
                   INCHWL(0);
                   <+Q>_045B);

SUBR READCMD(BF,FINAM,FREL,FLST,DEV,RPGM) IS (
# REL,LST_DEV:FILE.EXT[PJ,PG]/A/B...(AB...)PGM\% #
 FINAM[I]_0 FOR I FROM 5; DEV_'DSK';
 FREL_FREL[1]_FLST_FLST[1]_0;
 KEY IS 8 LONG; K_BYTEP ',_.[/(%'<7,36>;
 KEY[I]_DIR(<+K> LS 29) FOR I IN 1,1,7;
 CMA_KEY[1]; LAR_KEY[2];
 COL_DIR(':'); BSL_DIR('\');
 LEXSAV(); PC_BYTEP BF<7,36>;
 L0: LEX(S);
 L1: (S=KEY[I] => GO TO L2) FOR I IN 7,-1,1;
 L2: GO TO (K00,K1,K2,K3,K4,K5,K6,K7) I;
 K00: LEX(S1);
     S1=BSL => (NM IS 2 LONG; K_GNAME(S); NM_[K];
                NM[1]_[K+1]; RPGM_SIXBIT(NM); GO TO L0);
     S1=CMA => (PUTN(FREL,S,1); S_S1; GO TO L1);
     S1=LAR => (PUTN(FREL,S,1); GO TO L0);
     S1=COL => (PUTN(DEV,S,0); LEX(S); LEX(S1));
     PUTN(FINAM,S,1); S_S1; GO TO L1;
 K1: LEX(S); S=LAR=> GO TO L0;
     PUTN(FLST,S,1); GO TO L0;
 K2: GO TO L0;
 K3: LEX(S); PUTN(FINAM[2],S,0); GO TO L0;
 K4: LEX(S); PUTO(FINAM[3],S); LEX(S);
     LEX(S); PUTO(FINAM[4],S); LEX(S); GO TO L0;
 K5: LEX(S); PUTSW(FINAM[5],S); GO TO L0;
 K6: LEX(S); PUTSW(FINAM[5],S); LEX(S); GO TO L0;
 K7: FLST => FINAM[5]_FINAM[5] OR 4000B;
     FREL=0 => (FREL_FINAM; FREL[1]_FINAM[1]);
     FLST=0 => (FLST_FINAM; FLST[1]_FINAM[1]);
     LEXRES());

SUBR PUTN(X,S,N) IS (K_GNAME(S); X[I]_[K+I] FOR I FROM N);

SUBR PUTO(X,S) IS (X_0; K_GNAME(S); K_BYTEP [K]<7,36>;
                   WHILE I_<+K> DO X_(X LS 3)+I-060B);

SUBR PUTSW(X,S) IS (K_GNAME(S); K_BYTEP [K]<7,36>;
                    WHILE I_<+K> DO X_X OR 1 LS 37B AND I-101B) %%%