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BB-D480C-SB_1981
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strega.bli
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!THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY ONLY BE USED
! OR COPIED IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE.
!COPYRIGHT (C) 1972,1981 BY DIGITAL EQUIPMENT CORPORATION
!AUTHOR: S. MURPHY/HPW/DCE/SJW/JNG/TFV/EGM/EDS/AHM
MODULE STREGA(SREG=#17,VREG=#15,FREG=#16,DREGS=4,RESERVE(0,1,2,3)) =
BEGIN
GLOBAL BIND STREGV = 6^24 + 0^18 + 229; ! Version Date: 28-Oct-81
%(
***** Begin Revision History *****
178 ----- ----- ADD ROUTINES ALCE1LIST AND ALCE2LIST TO
PERFORM ALLOCATON FOR E1LISTCALL AND
E2LISTCALL NODES
179 ---- ----- MODIFY "ALCCALL" SO THAT DONT ASSUME ALL
REGS ARE CLOBBERED BY A CALL TO "ADJ1." AND "ADJG."
ALSO, INSERT CODE IN CMSTMN TO CHECK WHETHER A STMNT
INCLUDES ANY FN CALLS AND SET "FNCALLSFLG" IN
THE STMNT NODE IF IT DOES.
ALSO, REMOVE CODE FROM "CMSTMN" THAT CAUSED PAIRMODEFLG
TO NEVER BE SET IN AN IO STMNT (BECAUSE IO
STMNTS DIDNT HAVE FLAGS FIELDS ONCE UPON A TIME)
185 ----- ----- ADD CODE TO PROCESS COMMON SUBS ON CALL STMNTS
(HAVE SKIPPED SOME VERSION NUMBERS FOR THE
EXPERIMENTAL REGISTER 0 VERSION)
186 ----- ----- IN "ALCAIF" IF THE REG TO BE TESTED MUST FIRST
BE LOADED (IE IF "A1SAMEFLG" IS NOT SET), DO
NOT ALLOW REGISTER 0 TO BE USED (SINCE WE LOAD
THE REG WITH A SKIP INSTRUCTION)
187 ----- ----- IN "ALCASMNT", DO NOT CALL "ALCINTMP" TO
TARGET THE RHS TO THE LHS VAR IF THE LHS IS A
REGCONTENTS (THIS ONLY OCCURS IF "LHINREGALC"
HAS FAILED TO TARGET THE RHS TO THE LHS REG)
188 ----- ----- CORRECT TYPO IN 187
189 ----- ----- ADD CODE TO HANDLE AN ARBITRARY EXPRESSION
AS AN ARG IN AN OPEN STMNT
190 ----- ----- ADD CODE TO HANDLE AN ARBITRARY EXPRESSION
AS A UNIT NUMBER
191 ----- ----- FIX LHINREG TO CORRECTLY HANDLE DOUBLE
PRECISION ARRAYREF.
192 ----- ----- FIX ALCIOLIST TO PASS CORRECT DP REG BITS
193 ----- ----- MAKE ARRAY-REFS AS UNITS,RECORDS,AND UNDER OPEN/CLOSE
WORK BY CALLING "ALCTVARR" SO THAT A PTR TO THE STORECLS
NODE CAN BE LINKED UNDER THE STMNT NODE
194 ----- ----- CHANGE ALL CALLS TO THE MACRO "CLBNXREG"
INTO CALLS TO THE ROUTINE "CLOBBNX"
195 ----- ----- IN ALCE1LIST,ALCE2LIST, FOR COUNT OR INCR
AN ARRAY REF, LINK THE STORECLS NODE IN UNDER
THE E1/E2LISTCALL NODE
196 ----- ----- IN "LHINREGALC", WHEN ARE TARGETTING TO REG 0,
ALLOW REG 1 TO BE USED IN THE COMPUTATION
197 ----- ----- IN "ALCASMNT", WHEN CALL "SAVEREG" TO REMEMBER
THAT THE VAL OF RHS IS IN A REG - IF A1NEGFLG
WAS SET AND THE VAR IS DOUBLE-PREC, THE REGISTER
WILL BE NEGATED (SINCE THERE IS NO "MOVN" FOR DP)
HENCE THE REG WONT CONTAIN THE VAR
198 ----- ----- SAME FIX AS 197 - ANOTHER CALL TO "SAVEREG"
199 ----- ----- ONLY CALL FNVALCH1 IF WE ARE IN A FUNCTION
INSTEAD OF FOR EVERY ASSIGNMENT
200 ----- ----- IN ALCASMNT, IN LOCAL ROUTINE "SETREGFORA2VAL"
WHEN CHECK FOR SPECIAL CASE OF NEGATED AOBJN WD,
MUST NOW LOOK AT "A1NEGFLG" (FORMERLY A2NEGFLG)
201 ----- ---- IN STCMOPEN AND ALCOPEN, MUST CHECK FOR THE VAL
OF AN OPEN PARAM EQUAL TO ZERO BEFORE WALKING
DOWN THE TREE (SINCE THE ARG "DIALOG" CAN HAVE A
NULL VAL)
202 254 15425 FOR RELATIONALS, DO NOT ALLOCATE CMNSUB TO 0 SINCE
WE MIGHT HAVE JUST MADE A SETO 0,0
203 261 15772 CLEAR REGSTATE EACH STATEMENT IF DEBUG:LABELS
204 270 16013 CLEAR REGSTATE FOR ALL VARIABLES POSSIBLY CLOBBERED
IN A NAMELIST INPUT STATEMENT.
205 300 ----- FIX 204 TO ONLY CHECK RIGHT HALF FOR -1
206 301 16154 REALIZE THAT FUNCTION CALLS WILL CLOBBER ANY
ARGUMENTS LEFT IN 1 BY FUNCTION PROLOGS
207 310 16602 ALLOCATE UNIT BEFORE OPEN AND CLOSE ARGS
208 311 16665 ALLOCATE REGS IN ALCIOCALL ONLY FOR NON-DATA ITEMS
209 363 18269 PREVENT COMPLEMENTED VAR FROM BEING SAVED, (DCE)
210 403 18961 BAD CODE FOR I=I/J OR A=B*A, (DCE)
211 446 20652 BAD CODE FOR I=I*3 AND I=I**7 (QAR753), (SJW)
212 471 20309 BAD CODE FOR LOGICAL LHS IN COMMON OR EQUIVALENCE, (DCE)
213 503 19976 ON A(L) = FUNCT. CALL, DON'T LEAVE L IN REG 1.
IF EVALUATING LH FIRST, (JNG)
***** Begin Version 5A ***** 7-Nov-76
214 522 20819 ON AN ARRAYREF IN AN IOLIST WHEN WE'RE OUT OF
REGS, CHECK NEGFLGS BEFORE USING EXISTING REG
CONTAINING DESIRED SUBSCRIPT., (JNG)
215 527 20317 CLOBBER ALL COMMON OR EQUIV VARS ON RANDOM READ,
WRITE, FIND SINCE ASSOCIATE VAR IS UNKNOWN TO US!
216 532 20323 TREAT ARRAY AS ASSOCIATE VARIABLE CORRECTLY, (DCE)
217 546 22030 FIX OPERATIONS WHICH CLOBBER NEXT REGISTER (IDIV), (DCE)
218 616 22345 BE CAREFUL ALLOCATING NEW REGISTER FOR I/O LIST ELEMENT,
(DCE)
219 625 23122 SET INREGFLG IN LHINREGALC WHEN WE KNOW THAT
THE NODE WILL BE CALCULATED TO A REG. THIS
FIXES LOGICAL EXPRESSIONS LIKE A=A.OR.(X.GT.Y), (JNG)
***** Begin Version 5B *****
220 721 ----- A=A*B MUST INVALIDATE REGISTER FOR VARIABLE A
(IN CASE OTHER VARS LIVE THERE TOO)., (DCE)
221 744 28463 DOUBLE WORD ARRAY REFS IN I/O SLISTS AND ELISTS
MAY DOUBLY USE AN ODD NUMBERED REGISTER., (DCE)
***** Begin Version 6 *****
222 760 TFV 1-Oct-79 ------
Add handling for IOSTAT= variable, both in comlexity and in allocation
The variable is always clobbered (implicit assignment)
223 764 EGM 24-Apr-80 29279
Do not allocate a register for an I/O list element that is an
immediate array reference
224 1067 EDS 13-May-81 31074
Do not set register 1 available if there are any common subs
for this statement which have been allocated to register 1.
226 1123 AHM 21-Sep-81 Q20-01650
Make ALCIOS work for IOSTAT=arrayref
229 1142 EGM 28-Oct-81 Q10-06254
Prevent internal error when IOLISTCALL node complexity count is greater
than 63 (the 6 bits worth which is stored in the field).
***** End Revision History *****
)%
BIND REG0=0; !REGISTER 0 - THIS REG IS FREQUENTLY AN EXCEPTION
EXTERNAL
ALCTVARR,
CGERR,NXTTMP,ALOCONST,TBLSEARCH,C1H,C1L,DNEGCNST,MAKEPR,
MAKPR1;
FORWARD
CMSTMN(0),ALCSTMN(0),
STCMASMNT(0),STCMAGO(0),STCMCGO(0),STCMSTOP(0),
CMPDECENC(0),STCMCSB(0),ALCASMNT(0),ALCMEMCMP(0),ORDERMEMCMP(0),
ALCAGO(0),ALCCGO(0),
ALCDECENC(0),ALCOPEN(0),
ALCCMNSB(0),STCMLIF(0),STCMAIF(0),SCMASSI(0),STCMOPEN(0),
ALCE1LIST(3),ALCE2LIST(3),
ALCLIF(0),ALCAIF(0),ALCASSI(0),ALCCALL(0),ALCIOLST(0),
ALCIOCALL(1),LHINREGALC(0);
EXTERNAL EXCHARGS;
EXTERNAL
SETCOMPLEXITY,PRCNSTARG,ALCINREG,ALCARRAY,ALCINTMP;
EXTERNAL TREEPTR,GBSYREGS,GBSYCT,RESNAME;
EXTERNAL CSTMNT;
EXTERNAL STBSYR,STRGCT;
EXTERNAL STCMDO,ALCDOSTMT,ALCDOEND;
EXTERNAL ALCNARG;
EXTERNAL ALCENTRY, ALCRETURN,STCMSFN;
EXTERNAL CMPLIOLST;
EXTERNAL RGTOSAVE;
EXTERNAL ALCSFN;
EXTERNAL STCMRETURN;
EXTERNAL REGTOUSE,RGTOU1;
EXTERNAL SETTARGINREG;
EXTERNAL SETTAC;
EXTERNAL SAVREGCONTAINING; !ROUTINE IN BASIC BLOCK ALLOCATOR (MODULE "CMPBLO")
! WHICH CHECKS WHETHER A VAR COULD HAVE BEEN LEFT
! IN A REG FROM A PREV STMNT AND IF SO MARKS THAT STMNT
! TO LEAVE THE VAR
EXTERNAL ADDREGCANDATE; !ROUTINE IN BASIC BLOCK ALLOCATOR WHICH
! ADDS A VAR TO THE SET OF VARS THAT CAN BE LEFT IN REGS
EXTERNAL REGCLOBB; !THIS ROUTINE IS CALLED WHENEVER AN ALLOCATION IS PERFORMED
! WHICH WOULD CAUSE THE PREVIOUS CONTENTS OF A REG TO BE CLOBBERED
! IT CLEARS THE BB REG ALLOC ENTRIES FOR THAT REG
EXTERNAL VARCLOBB; !THIS ROUTINE IS CALLED WHENEVER A NODE IS PROCESSED
! WHICH WOULD CLOBBER THE VAL OF A VARIABLE. IT CLEARS ANY
! BB ALLOC ENTRIES THAT REFER TO THAT VAR
EXTERNAL NOBBREGSLOAD; !THIS FLAG IS TRUE WHEN NODES ARE BEING
! PROCESSED WHICH ARE NOT ALWAYS EXECUTED WHEN THE BLOCK
! IN WHICH THE ARE CONTAINED IS EXECUTED (EG FOR THE STMNT
! UNDER A LOG IF). WHEN THIS FLAG IS SET, CANNOT ASSUME
! THAT REGS SET BY EVAL OF THE NODE HAVE A GIVEN VAL
EXTERNAL CLRRGSTATE; !ROUTINE TO CLEAR THE BASIC BLOCK ALLOCATOR TABLES
! SO THAT ALL ASSUMPTIONS ABOUT THE CONTENTS OF REGS
! ARE NO LONGER HELD
EXTERNAL SAVEREG; !ROUTINE TO ADD A REGISTER TO THE SET OF REGS WHOSE
! CONTENTS THE BB ALLOCATOR KNOWS ABOUT
EXTERNAL INPFLAG; !THIS FLAG IS TRUE WHILE PROCESSING AN IOLSIST FOR
! A STMNT THAT DOES INPUT, FALSE WHILE PROCESSING AN IOLIST
! FOR A STMNT THAT DOES OUTPUT
EXTERNAL AFREEREG; !ROUTINE TO GET A FREE REGISTER TO USE. IF POSSIBLE,
! IT RETURNS A REG WHICH WILL NOT BE USEFUL LATER
! IN THIS BASIC BLOCK
! IF NOT, RETURNS THE REG WHOSE NEXT USE IS FURTHEST AWAY
EXTERNAL REGCONTAINING; !ROUTINE OF BASIC BLOCK ALLOCATOR WHICH
! CHECKS WHETHER ANY REG HOLDS A GIVEN VAR. IF SO IT
! IT RETURNS THE REG, IF NOT IT RETURNS -1
SWITCHES NOLIST;
REQUIRE FIRST.BLI;
REQUIRE TABLES.BLI;
SWITCHES LIST;
EXTERNAL DBLMODE; !THIS FLAG WORD IS SET WHEN A STATEMENT IS BEING
! ALLOCATED DOUBLE-PRECISION MODE (IE FOR AN ASSIGNMENT
! STMNT IF THE TOP-LEVEL EXPRESSIONS ARE DOUBLE-PRECISION)
MAP PEXPRNODE TREEPTR;
MAP BASE CSTMNT;
GLOBAL ROUTINE STREGA=
%(***************************************************************************
ROUTINE TO PERFORM LOCAL REGISTER ALLOCATION FOR A STATEMENT.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT.
CALLED WITH THE GLOBALS
STBSYR - HAS BIT SET FOR EACH REG AVAILABLE FOR USE IN EVALUATING
THIS STATEMENT
STRGCT - CT OF REGS AVAILABLE
***************************************************************************)%
BEGIN
%(***PERFORM COMPLEXITY ANALYSIS ON THE STMNT***)%
CMSTMN();
%(***PERFORM REGISTER ALLOCATION ON THE STMNT***)%
ALCSTMN();
END;
GLOBAL ROUTINE CMSTMN=
%(***************************************************************************
TO PERFORM COMPLEXITY ANALYSIS ON A STATEMENT.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMNET TO BE PROCESSED.
***************************************************************************)%
BEGIN
EXTERNAL CMPFNARGS;
EXTERNAL LPIXSUB; !ROUTINE TO SUBSTITUTE REGCONTENTS NODES FOR
! REFERENCES TO THE LOOP INDEXIN AN INNERMOST
! DO LOOP
EXTERNAL PAIRMODE; !GLOBAL WHICH WILL BE SET TO TRUE WHILE PERFORMING COMPLEXITY
! PASS OVER ANY NODE THAT REQUIRES AN ADJACENT
! PAIR OF REGISTERS
EXTERNAL STCMSUB;
GLOBAL FNREF; !GLOBAL THAT WILL GET SET IF ANY FN CALLS ARE
! ENCOUNTERED IN PROCESSING A STMNT
OWN PEXPRNODE RECNO; !PTR TO SYMBOL TABLE OR CONSTANT TABLE ENTRY
! FOR A RECORD NUMBER FOR AN IO STMNT
%(***DEFINE A ROUTINE TO USE TO ALLOCATE CORE FOR ANY CONSTANT USED AS
A RECORD NUMBER IN AN IO STMNT***)%
ROUTINE CMPRECNO=
BEGIN
IF (RECNO_.CSTMNT[IORECORD]) NEQ 0
THEN
BEGIN
IF .RECNO[OPR1] EQL CONSTFL
THEN ALOCONST(.RECNO)
%(***IF RECORD NUMBER IS AN EXPRESSION
PERFORM COMPLEXITY WALK ON IT***)%
ELSE
BEGIN
TREEPTR_.RECNO;
SETCOMPLEXITY();
END;
END
END;
ROUTINE CMPREPT=
%(***DEFINE ROUTINE FOR HANDLING REPT FIELDS OF IO STMNTS***)%
BEGIN
IF .CSTMNT[IOREPT] EQL 0
THEN
CSTMNT[SRCCMPLX]_0
ELSE
BEGIN
TREEPTR_.CSTMNT[IOREPT];
CSTMNT[SRCCMPLX]_SETCOMPLEXITY();
END
END;
ROUTINE CMPUNIT=
%(***DEFINE ROUTINE TO PERFORM COMPLEXITY WALK FOR A UNIT NUMBER
WHICH IS AN EXPRESSION OR ARRAY-REF**)%
BEGIN
TREEPTR_.CSTMNT[IOUNIT];
IF .TREEPTR[OPRCLS] NEQ DATAOPR !IF UNIT NOT A SIMPLE VAR OR CONST
THEN SETCOMPLEXITY()
END;
%[760]% ROUTINE CMPIOS=
%[760]% %(***Routine to perform complexity walk for an iostat variable which
is an array-ref***)%
%[760]% BEGIN
%[760]% IF .CSTMNT[IOIOSTAT] NEQ 0
%[760]% THEN
%[760]% BEGIN
%[760]% TREEPTR_.CSTMNT[IOIOSTAT];
%[760]% IF .TREEPTR[OPRCLS] NEQ DATAOPR ! not simple var
%[760]% THEN SETCOMPLEXITY();
%[760]% END;
%[760]% END;
%(***IF WE ARE IN A DO LOOP IN WHICH THE
LOOP INDEX LIVES IN A REGISTER, SUBSTITUTE "REGCONTENTS" NODES FOR
ALL REFERENCES TO THE LOOP INDEX THAT OCCUR IN THIS STMNT***)%
LPIXSUB();
PAIRMODE_FALSE; !INIT GLOBAL WHICH WILL BE USED TO DETERMINE WHETHER THIS
! STATEMENT INCLUDES ANY EXPRESSIONS THAT REQUIRE REGISTER PAIRS
FNREF_FALSE; !INIT GLOBAL THAT WILL BE USED TO DETERMINE WHETHER THIS STMNT
! CONTAINS ANY FN REFERENCES
%(***SRCID OF STMNT DETERMINES ACTION TO BE TAKEN***)%
CASE .CSTMNT[SRCID] OF SET
STCMASMNT(); !FOR ASSIGNMENT
SCMASSI(); ! ASSIGN
BEGIN ! CALL
CSTMNT[SRCCMPLX]_(IF .CSTMNT[CALLIST] EQL 0
THEN 0
ELSE CMPFNARGS(.CSTMNT[CALLIST],FALSE));
STCMCSB(); !PROCESS ANY COMMON SUBS
END;
CSTMNT[SRCCMPLX]_0; ! CONTINUE
STCMDO(); ! DO
STCMSUB(); ! ENTRY
STCMASMNT(); ! COMMON SUB (SAME AS ASMNT
CSTMNT[SRCCMPLX]_0; ! GOTO
STCMAGO(); ! ASSIGNED GOTO
STCMCGO(); ! COMPUTED GOTO
STCMAIF(); ! ARITHMETIC IF
STCMLIF(); ! LOGICAL IF
STCMRETURN(); ! RETURN
STCMSTOP(); ! STOP
BEGIN ! READ
CMPLIOLST();
CMPRECNO();
CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
BEGIN ! WRITE
CMPLIOLST();
CMPRECNO();
CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
%[760]% BEGIN ! DECODE
%[760]% CMPDECENC();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! ENCODE
%[760]% CMPDECENC();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! REREAD
%[760]% CMPLIOLST();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
BEGIN ! FIND
CSTMNT[SRCCMPLX]_0;
CMPRECNO();
CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
BEGIN ! CLOSE
STCMOPEN();
CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
CSTMNT[SRCCMPLX]_0; ! INPUT (NOT IN RELEASE 1)
CSTMNT[SRCCMPLX]_0; ! OUTPUT (NOT IN RELEASE 1)
%[760]% BEGIN ! BACKSPACE
%[760]% CMPREPT();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! BACKFILE
%[760]% CMPREPT();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! REWIND
%[760]% CSTMNT[SRCCMPLX]_0;
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! SKIPFILE
%[760]% CMPREPT();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! SKIP RECORD
%[760]% CMPREPT();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! UNLOAD
%[760]% CSTMNT[SRCCMPLX]_0;
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! RELEASE
%[760]% CSTMNT[SRCCMPLX]_0;
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
%[760]% BEGIN ! ENDFILE
%[760]% CMPREPT();
%[760]% CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
%[760]% END;
CSTMNT[SRCCMPLX]_0; ! END
STCMSTOP(); ! PAUSE
BEGIN ! OPEN
STCMOPEN();
CMPUNIT();
%[760]% CMPIOS(); ! set iostat complexity
END;
STCMSFN(); ! SFN
CSTMNT[SRCCMPLX]_0; ! FORMAT
CSTMNT[SRCCMPLX]_0; ! BLT (NOT IN RELEASE 1)
CSTMNT[SRCCMPLX]_0; ! GLOBAL ALLOCATOR ID
TES;
IF .PAIRMODE !IF ANY EXPRESSIONS WERE ENCOUNTERED THAT REQUIRED ADJACENT REG PAIRS
THEN CSTMNT[PAIRMODEFLG]_1; !SET FLAG IN STMNT
IF .FNREF THEN CSTMNT[FNCALLSFLG]_1; !IF ANY FN CALLS WERE ENCOUNTERED SET FLAG IN STMNT
END;
GLOBAL ROUTINE ALCSTMN=
%(***************************************************************************
ROUTINE TO PERFORM LOCAL REGISTER ALLOCATION FOR A STATEMENT.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT.
CALLED WITH THE GLOBALS
STBSYR - HAS BIT SET FOR EACH REG AVAILABLE FOR USE IN EVALUATING
THIS STATEMENT
STRGCT - CT OF REGS AVAILABLE
***************************************************************************)%
BEGIN
EXTERNAL INPFLAG; !GLOBAL FLAG THAT IS SET TO TRUE WHILE THE IOLIST
! OF A STATEMENT THAT DOES INPUT IS BEING PROCESSED (EG READ,DECODE)
! AND TO FALSE WHILE THE IOLIST OF A STATEMENT THAT DOES NOT
! DO INPUT IS BEING PROCESSED
EXTERNAL PAIRMODE; !DURING REG ALLOC PASS, IF THIS GLOBAL IS TRUE, WE
! WILL ASSUME THAT THE REGISTERS REQUIRED BY A
! GIVEN SUBEXPRESSION MUST ALL BE IN ADJACENT PAIRS
ROUTINE ALCREPT=
%(***DEFINE ROUTINE TO PERFORM REG ALLOC FOR REPT FIELD FOR AN IO STMNT***)%
BEGIN
IF .CSTMNT[IOREPT] NEQ 0
THEN
BEGIN
TREEPTR_.CSTMNT[IOREPT];
IF .TREEPTR[OPRCLS] NEQ DATAOPR !IF NOT A SIMPLE VAR OR CONST
THEN
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
END
END;
ROUTINE ALCUNIT=
%(***ROUTINE TO PERFORM REG ALLOC FOR A UNIT NUMBER WHICH IS
AN EXPRESSION OR ARRAYREF***)%
BEGIN
TREEPTR_.CSTMNT[IOUNIT];
IF .TREEPTR[OPRCLS] NEQ DATAOPR !IF NOT A SIMPLE VAR OR CONST
THEN
BEGIN
IF .TREEPTR[OPRCLS] EQL ARRAYREF
!FOR AN ARRAYREF - MUST LINK A STORECLS NODE UNDER THE STMNT NODE
THEN CSTMNT[IOUNIT]_ALCTVARR(.STBSYR,.STRGCT)
ELSE
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.STBSYR,.STRGCT)
END;
END;
%[760]% ROUTINE ALCIOS=
%[760]% %(*** Routine to perform reg alloc for an iostat variable
Note that the variable is always clobbered since
this is an implicit assignment***)%
%[760]% BEGIN
%1123% EXTERNAL ALCTARY; ! Wedges the address in a temp
%[760]% IF .CSTMNT[IOIOSTAT] NEQ 0
%[760]% THEN
%[760]% BEGIN
%[760]% TREEPTR_.CSTMNT[IOIOSTAT];
%[760]% IF .TREEPTR[OPRCLS] EQL ARRAYREF
%1123% THEN ! Store the address of the element and
%1123% ! indirect through it in the arg block
%1123% CSTMNT[IOIOSTAT]_ALCTARY(.STBSYR,.STRGCT);
%1123%
%[760]% VARCLOBB(.CSTMNT[IOIOSTAT]); ! always clobber var
%[760]% END;
%[760]% END;
EXTERNAL CLOBBCOMEQV;
ROUTINE ALCRANDIO=
%(*************
PERFORM REG ALLOC FOR RANDOM ACCESS IO.
MUST PERFORM ALLOCATION FOR THE CALC OF THE RECORD NUMBER
AND ALSO BB ALLOCATOR MUST ASSUME THAT THE VALS OF ALL ASSOCIATE
VARIABLES ARE CHANGED.
*************)%
BEGIN
REGISTER ASSCELEM; !AN ELEMENT ON THE LINKED LIST OF ASSOC-VAR PTRS
EXTERNAL ASSOCPT; !GLOBAL POINTING TO LIST OF ALL ASSOC VARS
! IN THIS SUBPROGRAM
IF (TREEPTR_.CSTMNT[IORECORD]) EQL 0 !IF DO NOT HAVE RANDOM ACCESS
THEN RETURN; ! NO PROCESSING IS NEEDED
IF .TREEPTR[OPRCLS] NEQ DATAOPR !IF THE RECORD NUMBER IS NOT A SIMPLE VAR OR CONST
THEN
BEGIN
IF .TREEPTR[OPRCLS] EQL ARRAYREF
!FOR AN ARRAYREF - MUST LINK A STORECLS NODE UNDER THE STMNT NODE
THEN CSTMNT[IORECORD]_ALCTVARR(.STBSYR,.STRGCT)
ELSE
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.STBSYR,.STRGCT)
END;
ASSCELEM_.ASSOCPT;
UNTIL .ASSCELEM<RIGHT> EQL 0 !LOOK AT ALL ASSOC VARS IN THE PROGRAM
! RIGHT HALF OF EACH ENTRY ON THE LINKED
! LIST PTS TO NEXT ELEM
DO
BEGIN
[email protected]<RIGHT>; !GET THE CONTENTS OF THE NEXT ELEMENT
VARCLOBB(.ASSCELEM<LEFT>); !LEFT HALF OF WD ON ASSOC VAR
! LIST PTS TO SYM TABLE ENTRY FOR THE VAR
END;
! IF THE OPEN OCCURS OUTSIDE THIS PROGRAM MODULE, THEN
!WE MUST ASSUME THAT ALL COMMON/EQUIV VARS ARE CLOBBERED
!SINCE THEY COULD BE ASSOCIATE VARIABLES!
CLOBBCOMEQV();
END;
ROUTINE CHECKNLIST (LISTPTR)=
%( CHECK THE LIST OF VARIABLES POINTED TO BY A NAMELIST NAME
AND CLEAR OUT ANY WHICH ARE CURRENTLY LIVING IN REGISTERS
SINCE THEY MAY BE CLOBBERED DURING AN INPUT REFERENCING
THAT NAMELIST NAME.
*************)%
BEGIN
REGISTER T1;
MAP BASE LISTPTR;
!LISTPTR POINTS TO A NAMELIST BLOCK CONTAINING POINTERS
! TO ALL THE VARIBLES SYMBOL TABLE ENTRIES
INCR I FROM 0 TO .LISTPTR[NAMCNT]-1 DO !SCAN THRU THE LIST OF POINTERS
BEGIN
T1_@(.LISTPTR[NAMLIST]+.I); !GET THE SYMBOL TABLE POINTER
VARCLOBB(.T1<RIGHT>); !GET RID OF IT IF IN REG
END;
END;
DBLMODE_FALSE; !FLAG WILL BE SET TO TRUE WHEN A STMNT IS PROCESSED
! IN DOUBLE-WD MODE (IE USES REG PAIRS). INITIALIZE IT TO FALSE.
IF .CSTMNT[PAIRMODEFLG] !IF THIS STMNT REQUIRES ANY ADJACENT REG PAIRS
THEN PAIRMODE_TRUE ! INIT GLOBAL INDICATING THAT AT LEAST
ELSE PAIRMODE_FALSE; ! ONE FREE PAIR SHOULD ALWAYS BE LEFT
IF .FLGREG<DBGLABL> !FORGET ABOUT OPTIMIZING REGISTER
THEN !USAGE ACROSS STATEMENTS IF FORDDT MAY CHANGE
CLRRGSTATE(); !VALUES IN CORE
%(***ACTION TO BE TAKEN IS DETERMINED BY THE SRCID***)%
CASE .CSTMNT[SRCID] OF SET
ALCASMNT(); !ASSIGNMENT
ALCASSI(); !ASSIGN
ALCCALL(); !CALL
BEGIN END; !CONTINUE
ALCDOSTMT(); !DO
ALCENTRY(); !ENTRY
ALCASMNT(); !COMMON SUB - SAME AS ASSIGNMENT
BEGIN END; ! GOTO
ALCAGO(); ! ASSIGNED GOTO
ALCCGO(); ! COMPUTED GOTO
ALCAIF(); ! ARITH IF
ALCLIF(); ! LOGICAL IF
ALCRETURN(); ! RETURN
BEGIN END; ! STOP
BEGIN ! READ
ALCRANDIO();
ALCUNIT();
INPFLAG_TRUE; !SET GLOBAL FLAG TO INDICATE THAT THE IOLIST TO BE
! PROCESSED DOES INPUT
IF .CSTMNT[IONAME] NEQ 0 !SEE IF NAMELIST
AND .CSTMNT[IONAME] NEQ #777777 !TYPE READ
THEN !YES
BEGIN
LOCAL BASE T1; !SEE IF NAMELIST
T1_.CSTMNT[IONAME]; !BIT IS ON IN SYMBOL
IF .T1[IDATTRIBUT(NAMNAM)] EQL 1 !TABLE ENTRY
THEN CHECKNLIST(.T1[IDCOLINK]); !THEN CLEAR ANY REGISTERS CONTAINING
END; !VARIBLES IN THE NAMELIST
ALCIOLST(); !PROCESS THE IOLIST
%[760]% ALCIOS(); ! process iostat
END;
BEGIN ! WRITE
ALCRANDIO();
ALCUNIT();
INPFLAG_FALSE; !SET GLOBAL FLAG TO INDICATE THAT THE IOLIST TO BE
! PROCESSED DOES NOT DO INPUT
ALCIOLST();
%[760]% ALCIOS(); ! process iostat
END;
BEGIN ! DECODE
INPFLAG_TRUE; !SET GLOBAL FLAG TO INDICATE THAT THE IOLIST TO BE
! PROCESSED DOES INPUT
ALCDECENC();
%[760]% ALCIOS(); ! process iostat
END;
BEGIN ! ENCODE
INPFLAG_FALSE; !SET GLOBAL FLAG TO INDICATE THAT THE IOLIST TO BE
! PROCESSED DOES NOT DO INPUT
ALCDECENC();
%[760]% ALCIOS(); ! process iostat
END;
BEGIN !REREAD
ALCUNIT();
INPFLAG_TRUE; !SET GLOBAL FLAG TO INDICATE THAT THE IOLIST TO BE
! PROCESSED DOES INPUT
ALCIOLST();
%[760]% ALCIOS(); ! process iostat
END;
%[760]% BEGIN ! FIND
%[760]% ALCRANDIO();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! CLOSE
%[760]% ALCUNIT();
%[760]% ALCOPEN();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
BEGIN END; ! INPUT (NOT IN RELEASE 1)
BEGIN END; ! OUTPUT (NOT IN RELEASE 1)
%[760]% BEGIN ! BACKSPACE
%[760]% ALCREPT();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! BACKFILE
%[760]% ALCREPT();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! REWIND
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! SKIPFILE
%[760]% ALCREPT();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! SKIPRECORD
%[760]% ALCREPT();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! UNLOAD
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! RELEASE
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
%[760]% BEGIN ! ENDFILE
%[760]% ALCREPT();
%[760]% ALCUNIT();
%[760]% ALCIOS(); ! process iostat
%[760]% END;
BEGIN END; !END
BEGIN END; !PAUSE
BEGIN ! OPEN
ALCUNIT();
ALCOPEN();
%[760]% ALCIOS(); ! process iostat
END;
ALCSFN(); !SFN
BEGIN END; !FORMAT
BEGIN END; !BLT (NOT IN RELEASE 1)
BEGIN !GLOBAL ALLOCATOR ID - INDICATING
! THAT SET OF REGISTERS AVAILABLE SHOULD CHANGE
GBSYREGS<LEFT>_.CSTMNT[NEWREGSET]; !SET OF REGS TO BE
! USED IN STMNTS FOLLOWING
GBSYCT_ONESCOUNT(.GBSYREGS);
END;
TES;
%(***IF THIS STMNT HAS A LABEL, PERFORM REG ALLOC FOR ANY DO-LOOP TERMINATION
IMPLIED BY THAT LABEL****)%
IF .CSTMNT[SRCLBL] NEQ 0
THEN ALCDOEND(.CSTMNT[SRCLBL]);
END;
GLOBAL ROUTINE STCMASMNT=
%(***************************************************************************
ROUTINE TO PERFORM THE COMPLEXITY PASS FOR AN ASSIGNMENT
STATEMENT.
DETERMINES THE NUMBER OF REGS NECESSARY FOR COMPUTATION OF THE
LEFT AND RIGHT SIDES AND FOR ALL COMMON SUBEXPRESSIONS.
DETERMINES WHICH SIDE SHOULD BE COMPUTED FIRST.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT NODE.
THIS ROUTINE IS NOT CALLED RECURSIVELY.
***************************************************************************)%
BEGIN
EXTERNAL ORDERMEMCMP; !ROUTINE TO ORDER THE ARGS OF AN OP TO MEMORY
! SO THAT ARG2 IS IDENTICAL TO THE LHS OF THE ASSIGNMENT STMNT
EXTERNAL FNVLCH1; !CHECK FOR ASSIGNMENT OF FN VAL DIRECTLY BEFORE RETURN
OWN CMPLX1:CMPLX2;
OWN PEXPRNODE ARG1NODE;
OWN PEXPRNODE LHNODE;
OWN PEXPRNODE RHNODE;
IF .FLGREG<PROGTYP> EQL FNPROG
THEN
FNVLCH1(); !KEEP A CT OF ASSIGNMENTS OF THE FN VAL THAT DIRECTLY
! PRECEDE RETURN STMNTS
RHNODE_.CSTMNT[RHEXP];
LHNODE_.CSTMNT[LHEXP];
IF .CSTMNT[MEMCMPFLG] !IF THIS ASSIGNMENT WILL BE PERFORMED TO MEMORY
AND .RHNODE[OPRCLS] NEQ SPECOP ! AND THE OPERATION IS ARITHMETIC OR BOOLEAN
THEN
BEGIN
ORDERMEMCMP(); !ORDER THE ARGS UNDER RHS SO THAT THE ARG THAT MATCHES LHS IS ARG2
ARG1NODE_.RHNODE[ARG1PTR]; !GET PTR TO ARG NOT IDENTICAL TO LHS
IF .ARG1NODE[OPERATOR] EQL INTCONST !IF THAT ARG IS THE INTEGER CONSTANT
AND .ARG1NODE[CONST2] EQL 1 ! ONE
AND .RHNODE[OPERATOR] EQL INTADD !AND THE OPERATION IS INTEGER ADD (OR SUB)
THEN RHNODE[OPTOBOTHFLG]_1; !THEN PERFORM THIS OP TO BOTH RATHER THAN
! TO MEMORY (SO THAT CAN PEEPHOLE AOS AND SOS)
END;
IF .CSTMNT[A1VALFLG]
THEN
%(***IF LHS IS A SIMPLE VARIABLE, SET UP PTR TO THE SYMBOL TABLE ENTRY***)%
BEGIN
RESNAME_.CSTMNT[LHEXP];
CMPLX1_0;
END
ELSE
%(***IF LHS REQUIRES EVALUATION (IE IS AN ARRAY REFERENCE), DETERMINE NUMBER OF
REGS NEEDED FOR THAT CALC***)%
BEGIN
TREEPTR_.CSTMNT[LHEXP];
CMPLX1_SETCOMPLEXITY();
RESNAME_.LHNODE[ARG1PTR];
END;
%(***DETERMINE THE NUMBER OF REGS NECESSARY FOR EVALUATION OF RHS***)%
IF NOT .CSTMNT[A2VALFLG]
THEN
BEGIN
TREEPTR_.CSTMNT[RHEXP];
CMPLX2_SETCOMPLEXITY();
END;
%(***IF RIGHT HAND SIDE IS A VARIABLE OR A CONSTANT, STILL NEED ONE REG TO LOAD THE VAL INTO***)%
IF .RHNODE[OPRCLS] EQL DATAOPR
THEN
BEGIN
CMPLX2_1;
%(***IF RHNODE IS A CONSTANT, DETERMINE WHETHER IT IS
AN IMMED CONSTANT AND IF NOT ALLOCATE CORE FOR IT***)%
IF .RHNODE[OPR1] EQL CONSTFL
THEN
PRCNSTARG(.CSTMNT,.RHNODE,FALSE);
%(**IF RHS COULD HAVE BEEN LEFT IN A REG EARLIER, DO SO**)%
SAVREGCONTAINING(.RHNODE);
%(**IF THE VAR ON THE RHS IS NEEDED LATER, WILL BE ABLE TO USE
IT FROM THE REG USED FOR THIS ASMNT**)%
ADDREGCANDATE(.RHNODE,.CSTMNT);
END;
%(***IF THE RHS IS DOUBLE-PREC, NEED TWICE AS MANY REGS AS HAVE COMPUTED***)%
IF .RHNODE[DBLFLG] THEN CMPLX2_2*.CMPLX2;
%(***SET FIELD IN THE ASSIGNMENT-STMNT NODE TO INDICATE THE NUMBER OF REGS
NECESSARY TO EVAL THE STMNT EXCLUSIVE OF COMMON SUBEXPRS***)%
CSTMNT[SRCCMPLX]_
(IF .CMPLX1 GTR .CMPLX2
THEN .CMPLX1
ELSE
IF .CMPLX2 GTR .CMPLX1
THEN .CMPLX2
ELSE .CMPLX1+1 );
%(***PERFORM COMPLEXITY ANALYSIS FOR EACH COMMON SUBEXPRESSION UNDER
THIS NODE*******)%
STCMCSB();
%(**IF THE LHS VAR IS NEEDED LATER, IT CAN BE USED DIRECTLY FROM THE REG
USED FOR THIS ASMNT***)%
IF .CSTMNT[A1VALFLG] THEN ADDREGCANDATE(.LHNODE,.CSTMNT);
END;
GLOBAL ROUTINE STCMAGO=
%(***************************************************************************
ROUTINE TO COMPUTE THE COMPLEXITY OF AN ASSIGNED GOTO
***************************************************************************)%
BEGIN
%(***COMPUTE COMPLEXITY OF THE ASSIGNED VAL (MAY BE AN ARRAY-REF***)%
TREEPTR_.CSTMNT[AGOTOLBL];
IF .TREEPTR[OPRCLS] EQL DATAOPR
THEN
CSTMNT[SRCCMPLX]_0
ELSE
CSTMNT[SRCCMPLX]_SETCOMPLEXITY();
%(***FIND COMPLEXITY OF ANY COMMON SUBEXPRS***)%
STCMCSB();
END;
GLOBAL ROUTINE STCMCGO=
%(***************************************************************************
ROUTINE TO COMPUTE COMPLEXITY OF A COMPUTED GOTO
***************************************************************************)%
BEGIN
%(***CALCULATE THE COMPLEXITY OF THE EXPRESSION TO BE COMPUTED***)%
TREEPTR_.CSTMNT[CGOTOLBL];
IF .TREEPTR[OPRCLS] EQL DATAOPR
THEN
BEGIN
IF .TREEPTR[OPR1] EQL CONSTFL THEN ALOCONST(.TREEPTR);
CSTMNT[SRCCMPLX]_0
END
ELSE
CSTMNT[SRCCMPLX]_SETCOMPLEXITY();
%(***FIND COMPLEXITY OF ANY COMMON SUBEXPRS***)%
STCMCSB();
END;
GLOBAL ROUTINE STCMSTOP=
%(***************************************************************************
ROUTINE TO PERFORM THE COMPLEXITY FOR STOP AND PAUSE.
THE ARG FOR STOP/PAUSE CAN ONLY BE A VARIABLE OR A CONSTANT OR
LITERAL (CANNOT BE AN EXPRESSION).
MUST ALLOCATE THE CONSTANT OR LITERAL IF THERE IS ONE.
***************************************************************************)%
BEGIN
OWN PEXPRNODE STOPEXPR;
IF (STOPEXPR_.CSTMNT[STOPIDENT]) NEQ 0
THEN
BEGIN
IF .STOPEXPR[OPR1] EQL CONSTFL
THEN ALOCONST(.STOPEXPR);
END;
CSTMNT[SRCCMPLX]_0;
END;
GLOBAL ROUTINE STCMLIF=
%(***************************************************************************
ROUTINE TO PERFORM THE COMPLEXITY PASS FOR A LOGICAL IF.
DETERMINES THE NUMBER OF REGS NECESSARY FOR COMPUTATION OF
THE LOGICAL EXPRESSION AND FOR THE SUBSTATEMENT AND FOR ANY COMMON SUBEXPRS.
SETS THE COMPLEXITY OF THE STATEMENT TO THE MAXIMUM OF THESE.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT TO BE PROCESSED.
THIS ROUTINE IS NEVER CALLED RECURSIVELY (SINCE IT IS ILLEGAL TO EMBED
A LOGICAL IF INSIDE ANOTHER)
***************************************************************************)%
BEGIN
EXTERNAL CMPLREL,CMPLBL;
EXTERNAL PAIRMODE; !GLOBAL THAT GETS SET WHEN PROCESSING A STMNT THAT USES ANY REG PAIRS
EXTERNAL FNREF; !GLOBAL THAT GETS SET WHEN PROCESSING A STMNT THAT CONTAINS FN CALLS
LOCAL CEXPRPAIRMODE; !VALUE OF "PAIRMODE" FOR THE CONDITIONAL EXPR
! (TRUE IFF THE COND USES ANY REG PAIRS)
LOCAL CEXPRFNREF; !VALUE OF "FNREF" FOR THE CONDITIONAL EXPR (TRUE IFF
! THERE ARE ANY FN CALLS IN THE CEXPR)
OWN PEXPRNODE CONDEXPR;
OWN BASE SAVSTMNT; !SAVE PTR TO THIS STMNT
%(***PERFORM COMPLEXITY ANALYSIS ON THE CONDITIONAL EXPR***)%
CONDEXPR_.CSTMNT[LIFEXPR];
TREEPTR_.CONDEXPR;
%(****FOR RELATIONALS AND CONTROL-TYPE BOOLEANS, NEED NEVER COMPUTE A VALUE***)%
IF .CONDEXPR[VALTYPE] EQL CONTROL
THEN
BEGIN
IF .CONDEXPR[OPRCLS] EQL BOOLEAN
THEN
CSTMNT[SRCCMPLX]_CMPLBL()
ELSE
IF .CONDEXPR[OPRCLS] EQL RELATIONAL
THEN
CSTMNT[SRCCMPLX]_CMPLREL()
ELSE
CGERR()
END
%(***FOR EXPRESSIONS WHICH DO NOT HAVE VALTYPE CONTROL, WILL COMPUTE A VAL AND TEST IT***)%
ELSE
BEGIN
%(***IF CONDEXPR IS A CONSTANT, THIS STMNT WILL HAVE BEEN FOLDED AWAY IN
P2SKEL IF P2SKEL IS USED; IF P2SKEL IS NOT USED, A CONSTANT
CONDEXPR IS ALLOCATED TO CORE****)%
IF .CONDEXPR[OPR1] EQL CONSTFL THEN ALOCONST(.TREEPTR);
CSTMNT[SRCCMPLX]_SETCOMPLEXITY();
END;
CEXPRPAIRMODE_.PAIRMODE; !SAVE KNOWLEDGE OF WHETHER THE COND EXPR USED ANY REG PAIRS
CEXPRFNREF_.FNREF; !SAVE KNOWLEDGE OF WHETHER THE COND EXPR HAD ANY FN CALLS
%(***COMPUTE THE COMPLEXITY OF THE SUBSTATEMNT***)%
SAVSTMNT_.CSTMNT; !SAVE PTR TO THIS STMNT
CSTMNT_.CSTMNT[LIFSTATE];
CMSTMN();
%(**THE IF STATEMENT REQUIRES AT LEAST AS MANY REGS AS ARE NECESSARY FOR
COMPUTATION OF THE SUBSTATEMENT***)%
IF .SAVSTMNT[SRCCMPLX] LSS .CSTMNT[SRCCMPLX]
THEN
SAVSTMNT[SRCCMPLX]_.CSTMNT[SRCCMPLX];
CSTMNT_.SAVSTMNT; !RESTORE VAL OF CSTMNT
%(***PERFORM COMPLEXITY ANALYSIS FOR COMMON SUBEXPRS***)%
STCMCSB();
PAIRMODE_.PAIRMODE OR .CEXPRPAIRMODE; !THE IF REQUIRES A REG PAIR IF EITHER THE COND EXPR
! OR THE SUBSTMNT REQUIRES ONE
FNREF_.FNREF OR .CEXPRFNREF; !THE IF STMNT CONTAINS A FN REF IF EITHER THE
! COND EXPR OR THE SUBSTMNT DOES
END;
GLOBAL ROUTINE STCMAIF=
%(***************************************************************************
ROUTINE TO PERFORM THE COMPLEXITY PASS FOR AN ARITHMETIC IF.
DETERMINES THE NUMBER OF REGS NECESSARY FOR COMPUTATION OF THE
ARITHMETIC EXPRESSION AND FOR ANY COMMON SUBEXPRESSIONS.
SETS THE COMPLEXITY OF THE STATEMENT TO THE MAX OF THESE.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT FOR
WHICH ANALYSIS IS TO BE PERFORMED.
***************************************************************************)%
BEGIN
%(***PERFORM COMPLEXITY ANALYSIS OF THE ARITH EXPR***)%
TREEPTR_.CSTMNT[AIFEXPR];
%(***IF THE ARITH EXPR IS A VARIABLE, WILL STILL USE A REG TO HOLD THE VAL***)%
IF .TREEPTR[OPRCLS] EQL DATAOPR
THEN
BEGIN
SAVREGCONTAINING(.TREEPTR); !IF BB ALLOCATOR CAN LEAVE THIS VAR IN A
! REG, HAVE IT DO SO
%(***IF CONDEXPR IS A CONSTANT, THIS STMNT WILL HAVE BEEN FOLDED AWAY IN
P2SKEL IF IT WAS USED; IF P2SKEL NOT USED, A CONSTANT CONDEXPR
IS ALLOCATED TO CORE****)%
IF .TREEPTR[OPR1] EQL CONSTFL THEN ALOCONST(.TREEPTR);
CSTMNT[SRCCMPLX]_1
END
ELSE
CSTMNT[SRCCMPLX]_SETCOMPLEXITY();
%(***PERFORM COMPLEXITY ANALYSIS FOR ANY COMMON SUBEXPRSSIONS***)%
IF .CSTMNT[SRCCOMNSUB] NEQ 0
THEN STCMCSB();
END;
GLOBAL ROUTINE SCMASSI=
%(***************************************************************************
PERFORM COMPLEXITY ANALYSIS FOR AN ASSIGN STMNT.
***************************************************************************)%
BEGIN
EXTERNAL CMPLXARRAY;
TREEPTR_.CSTMNT[ASISYM];
%(***IF VAR ASSIGNED TO IS AN ARRAYREF, PERFORM COMPLEXITY ANALYSIS ON IT***)%
IF .TREEPTR[OPRCLS] EQL ARRAYREF
THEN
BEGIN
CSTMNT[SRCCMPLX]_CMPLXARRAY();
IF .CSTMNT[SRCCMPLX] EQL 0 THEN CSTMNT[SRCCMPLX]_1;
END
ELSE
CSTMNT[SRCCMPLX]_1;
END;
GLOBAL ROUTINE STCMOPEN=
%(***************************************************************************
TO PERFORM COMPLEXITY PASS FOR AN OPEN STATEMENT.
MUST ALLOCATE ALL CONSTANTS THAT OCCUR UNDER THIS STMNT.
***************************************************************************)%
BEGIN
REGISTER PEXPRNODE ARGVAL; !PTR TO SYMBOL OR CONSTANT TABLE ENTRY
! FOR THE VALUE TO BE PASSED TO FOROTS
! FOR A GIVEN ARG
REGISTER OPENLIST ARVALLST; !LIST OF ARGS UNDER THIS OPEN STMNT
OWN CMPLXMAX; !MAXIMUM COMPLEXITY OF THE ARGS
ARVALLST_.CSTMNT[OPLST];
CMPLXMAX_0;
%(***WALK THRU THE LIST OF ARGS - FOR ANY ARG THAT IS A CONSTANT OR A LITERAL
ALLOCATE CORE FOR THAT CONSTANT/LITERAL***)%
INCR I FROM 0 TO (.CSTMNT[OPSIZ]-1)
DO
BEGIN
ARGVAL_.ARVALLST[.I,OPENLPTR];
IF .ARGVAL EQL 0 !FOR THE PARAM "DIALOG" MAY HAVE
THEN BEGIN END ! A NULL ARG; DO NOTHING
ELSE
IF .ARGVAL[OPRCLS] EQL DATAOPR !VAL A VAR OR CONST
THEN
(IF .ARGVAL[OPR1] EQL CONSTFL THEN ALOCONST(.ARGVAL)) !ALLOCATE CORE FOR A CONST
ELSE !VAL AN EXPRESSION (OR ARRAYREF)
BEGIN
REGISTER CMPL1;
%(**PERFORM "COMPLEXITY" PASS OVER THIS EXPRESSION,
IF ITS COMPLEXITY IS GTR THAN THE MAXIMUM, CHANGE THE MAXIMUM**)%
TREEPTR_.ARGVAL;
IF (CMPL1_SETCOMPLEXITY()) GTR .CMPLXMAX
THEN CMPLXMAX_.CMPL1;
END;
END;
CSTMNT[SRCCMPLX]_.CMPLXMAX;
END;
GLOBAL ROUTINE CMPDECENC=
%(***************************************************************************
TO PERFORM COMPLEXITY PASS FOR AN ENCODE OR DECODE STMNT.
THE ENCODE VAR MAY BE AN ARRAY REF THAT NEEDS TO HAVE AN ADDRESS CALC
PERFORMED.
***************************************************************************)%
BEGIN
EXTERNAL CMPLXARRAY,TREEPTR;
OWN CMPL1;
OWN PEXPRNODE ENCVAR;
OWN PEXPRNODE ENCCT;
ENCVAR_.CSTMNT[IOVAR]; !ENCODE/DECODE VARIABLE
ENCCT_.CSTMNT[IOCNT]; !CHAR CT
%(***IF CHAR CT IS AN EXPRESSION, PERFORM COMPLEXITY ANALYSIS FOR ITS
CALCULATION***)%
IF .ENCCT[OPRCLS] NEQ DATAOPR
THEN
BEGIN
TREEPTR_.ENCCT;
SETCOMPLEXITY()
END;
%(***IF ENCODE/DECODE VARIABLE IS AN ARRAY REF (RATHER THAN A SYMBOL TABLE
ENTRY FOR AN ARRAY NAME) - PERFORM COMPLEXITY PASS ON ADDRESS CALCULATION***)%
IF .ENCVAR[OPRCLS] EQL ARRAYREF
THEN
BEGIN
TREEPTR_.ENCVAR;
CMPL1_CMPLXARRAY()
END
ELSE
IF .ENCVAR[OPRCLS] EQL DATAOPR
THEN CMPL1_0
ELSE CGERR();
CMPLIOLST(); !PERFORM COMPLEXITY ANALYSIS ON THE IOLIST
! LEAVE THE STMNT COMPLEXITY FIELD SET TO THE NUMBER
! OF REGS NECESSARY FOR COMP OF THE IOLIST
%(***IF THE ADDR CALC FOR THE ENCODE VAR REQUIRES MORE REGS THAN CALC
OF THE IOLIST DOES, ADJUST THE COMPLEXITY FIELD OF THE STMNT***)%
IF .CMPL1 GTR .CSTMNT[SRCCMPLX]
THEN CSTMNT[SRCCMPLX]_.CMPL1;
END;
GLOBAL ROUTINE STCMCSB=
%(***************************************************************************
ROUTINE TO PERFORM COMPLEXITY ANALYSIS FOR EACH COMMON SUBEXPR UNDER THE NODE
POINTED TO BY CSTMNT.
LEAVES THE COMPLEXITY FIELD OF THE STATEMENT SET TO THE MAX OF ITS
INITIAL VAL AND THE MAX COMPLEXITY OF ANY COMMON SUB
***************************************************************************)%
BEGIN
OWN CMPLX1;
REGISTER PEXPRNODE CCMNSUB;
CCMNSUB_.CSTMNT[SRCCOMNSUB];
UNTIL .CCMNSUB EQL 0
DO
BEGIN
IF .CCMNSUB[A2VALFLG] !IF THIS CSB IS A SINGLE VARIABLE
THEN
BEGIN
SAVREGCONTAINING(.CCMNSUB[ARG2PTR]); !IF THE CSB COULD HAVE BEEN
! LEFT IN A REG BY A PREV STMNT, DO LEAVE IT
ADDREGCANDATE(.CCMNSUB[ARG2PTR],.CCMNSUB); !IF THIS VAR SHOULD BE NEEDED LATER
! WILL BE ABLE TO USE IT FROM THE
! REG WHERE THIS STMNT LEFT IT
CCMNSUB[COMPLEXITY]_0;
END
ELSE !IF THE CSB IS AN EXPRESSION
BEGIN
TREEPTR_.CCMNSUB[ARG2PTR];
CMPLX1_SETCOMPLEXITY();
IF .CMPLX1 GTR .CSTMNT[SRCCMPLX]
THEN CSTMNT[SRCCMPLX]_.CMPLX1;
CCMNSUB[COMPLEXITY]_.CMPLX1;
END;
CCMNSUB_.CCMNSUB[CLINK];
END;
END;
GLOBAL ROUTINE ALCASMNT=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ASSIGNMENT STATEMENT.
DETECTS OPERATONS OF THE FORM:
A=A+B+C+...
A=A*B*C....
TO BE OPERATIONS TO MEMORY.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT NODE FOR
WHICH ALLOCATION IS TO BE PERFORMED.
THIS ROUTINE IS NEVER CALLED RECURSIVELY.
***************************************************************************)%
BEGIN
EXTERNAL FNVALCHK; !ROUTINE TO CHECK FOR THE CASE OF AN ASSIGNMENT OF A FN VAL
! DIRECTLY PRECEEDING A RETURN
OWN PEXPRNODE ARGNODE:LHNODE:RHNODE;
OWN RA,RB;
OWN PEXPRNODE SUBNODE;
OWN RSV;
%(***TO SET THE REG FOR COMPUTATION OF THE STATEMENT TO THE SAME REG
INTO WHICH THE RIGHT-HAND SIDE WAS COMPUTED***)%
MACRO SETREGTORH=
BEGIN
CSTMNT[ASMNTREG]_.RHNODE[TARGTAC];
CSTMNT[A2SAMEFLG]_1;
END$;
ROUTINE USEAFREEREG=
%(*****ROUTINE TO GET A LEGAL REG FOR COMPUTATION OF THE ASSIGNMENT AND
SET THE REG-TO-BE-USED TO THAT REG*****)%
BEGIN
RA_REGTOUSE(.CSTMNT,.RHNODE,.LHNODE,.RA,.STBSYR);
CSTMNT[ASMNTREG]_.RA; !SET THE REG TO BE USED FOR THE
! ASSIGNMENT TO RA
REGCLOBB(.RA); !MUST ASSUME THAT PREVIOUS CONTENTS OF
! RA ARE CLOBBERED. CLEAR BASIC BLOCK ALLOC
! TABLE ENTRIES FOR RA
IF .RHNODE[DBLFLG] !IF THE VAL BEING ASSIGNED USES 2 WDS
THEN !MUST ALSO ASSUME THAT THE REG AFTER
REGCLOBB(.RA+1); ! RA IS CLOBBERED
END;
ROUTINE SETREGFORA2VAL=
%(***ROUTINE TO SET THE "REG FOR COMP" OF THE STMNT WHEN THE RIGHT HAND SIDE IS
A VARIABLE OR REGCONTENTS (IE WHEN A2VALFLG IS SET)***)%
BEGIN
IF .RHNODE[OPRCLS] EQL REGCONTENTS
THEN
%(***IF RHS IS A VAR WHICH LIVES IN A REG, WILL USUALLY WANT TO SET
REG-FOR-COMP OF STMNT TO THAT REG***)%
BEGIN
%(***HAVE THE EXCEPTION THAT IF THE RHS IS AN AOBJN WORD
FOR A LOOP CONTROL, WANT TO USE ONLY THE RIGHT HALF.
THIS IS A PROBLEM IFF EITHER A2NEGFLG OR A2NOTFLG IS SET,
IN WHICH AN EXTRA REG WILL BE NEEDED.
*******)%
IF .CSTMNT[A2IMMEDFLG] AND
(.CSTMNT[A1NEGFLG] OR .CSTMNT[A1NOTFLG]
OR .CSTMNT[A2NEGFLG] OR .CSTMNT[A2NOTFLG])
THEN
USEAFREEREG()
ELSE
SETREGTORH
END
ELSE
IF (RB_REGCONTAINING(.RHNODE)) GEQ 0 !IF THE RIGHT HAND SIDE WAS LEFT IN
! A REG BY AN EARLIER STMNT IN THIS BASIC BLOCK
AND .CSTMNT[A2NGNTFLGS] EQL 0 !AND THE RHS WILL NOT BE PICKED UP
! BY A MOVN
THEN
BEGIN
CSTMNT[ASMNTREG]_.RB; !USE THAT REG FOR THE ASSIGNMENT
CSTMNT[A2SAMEFLG]_1; !NEED NOT RELOAD THE REG
CSTMNT[A2IMMEDFLG]_0; !IF THE RHS WAS PREVIOUSLY AN IMMED CONST, WOULD
! HAVE HAD THIS FLAG SET. MUST BE CAREFUL
! TO TURN IT OFF BECAUSE THE ONLY PLACE THAT
! WE CAN HAVE "A2SAMEFLG" AND "A2IMMEDFLG"
! BOTH SET IS FOR RHS AN AOBJN REG
REGCLOBB(.RB); !DELETE THE PREVIOUS ENTRY IN THE "REGSTATE"
! TABLE FOR RB (SINCE WE CAN ONLY REMEMBER
! A MAX OF 2 VARS PER REG)
END
ELSE
%(***IF RHS IS A VARIABLE WHICH DOES NOT LIVE IN A REG, SET REG
FOR COMP OF STMNT TO RA****)%
USEAFREEREG()
END;
FNVALCHK(); !IF LHS OF THIS STMNT IS THE FN ENTRY NAME (IE IS THE VAL TO BE RETURNED)
! AND THE NEXT STMNT IS A RETURN, SUBSTITUTE A REGCONTENTS 0 FOR THE LHS
RHNODE_.CSTMNT[RHEXP];
LHNODE_.CSTMNT[LHEXP];
%(****PERFORM REGISTER ALLOCATION FOR THE COMMON SUBEXPRS UNDER THIS STMNT.****)%
DBLMODE_FALSE;
ALCCMNSB();
%(***IF THIS STATEMENT IS DOUBLE-PREC, ADJUST SET OF BUSY REGS SO
THAT ONLY EVEN REGS WILL BE ALLOCATED****)%
IF .RHNODE[DBLFLG]
THEN
BEGIN
STBSYR_DPBSYREGS(.STBSYR);
STRGCT_ONESCOUNT(.STBSYR);
DBLMODE_TRUE;
END
ELSE DBLMODE_FALSE;
%(****IF THE LEFT-HAND SIDE OF THE ASSIGNMENT IS A VARIABLE THAT WAS ALLOCATED
TO LIVE IN A REGISTER, WILL PROCESS THE RIGHT-HAND SIDE IN A SPECIAL
MANNER*****)%
IF .LHNODE[OPRCLS] EQL REGCONTENTS
THEN
BEGIN
IF .CSTMNT[MEMCMPFLG]
THEN
BEGIN
CSTMNT[MEMCMPFLG]_0; !IF IN P2SKEL HAD DECIDED TO PERFORM THIS
! OP TO MEMORY - UNDO THAT DECISION
RHNODE[MEMCMPFLG]_0;
CSTMNT[OPTOBOTHFLG]_0; ! (ALSO UNDO DECISION TO DO OP "TO BOTH")
RHNODE[OPTOBOTHFLG]_0;
END;
IF LHINREGALC() THEN RETURN;
END;
%(***IF THE RIGHT-HAND SIDE IS TO BE COMPUTED DIRECTLY TO MEMORY*****)%
IF .CSTMNT[MEMCMPFLG]
THEN
BEGIN
ALCMEMCMP();
RETURN;
END;
RA_AFREEREG(.STBSYR,.CSTMNT[SRCSAVREGFLG],.LHNODE[DBLFLG]);
%(***IF RIGHT HAND SIDE IS AN EXPRESSION WHOSE VAL MUST BE NEGATED BY AN EXTRA MOVN
(IE IT IS NOT A DATA ITEM OR ARRAYREF THAT WOULD HAVE TO BE PICKED UP ANYWAY)
OR IF LEFT HAND SIDE IS AN ARRAYREF (AND HENCE THERE IS NO VALUE IN
LEAVING ITS VAL IN A REG FOR FUTURE USES) AND THE RHS IS A SIMPLE
VAR (AND HENCE ITS VAL MIGHT BE USEFUL IN A REG)
SHOULD DO THE NEGATE AS A PART OF THE STORE OPERATION
HENCE IN THESE CASES SHOULD PUT NEG (AND NOT) FLAGS OVER LEFT
RATHER THAN RIGHT HAND SIDE***)%
IF (.RHNODE[OPRCLS] NEQ DATAOPR AND .RHNODE[OPRCLS] NEQ ARRAYREF)
OR
( NOT .CSTMNT[A1VALFLG]
AND .CSTMNT[A2VALFLG] !AND RHS IS A SIMPLE VAR
! (NB FOR A(I)=-A(I)
! WANT TO CREATE THE PEEPHOLE
! MOVN, MOVEM)
AND NOT (.RHNODE[OPERATOR] EQL INTCONST
AND .RHNODE[CONST2] EQL 1) !AND RHS IS NOT INTEGER 1
! (BECAUSE WE WANT TO GET THE
! MOVNI 1, MOVEM PEEPHOLE)
)
THEN
BEGIN
CSTMNT[A1NEGFLG]_.CSTMNT[A2NEGFLG]; !(A1NEGFLG WOULD NOT HAVE PREVIOUSLY BEEN SET)
CSTMNT[A1NOTFLG]_.CSTMNT[A2NOTFLG];
CSTMNT[A2NEGFLG]_0;
CSTMNT[A2NOTFLG]_0;
END;
%(***IF LEFT HAND SIDE OF STATEMENT IS A SIMPLE VARIABLE, PERFORM REGISTER
ALLOCATION FOR THE RIGHT HAND SIDE****)%
IF .CSTMNT[A1VALFLG]
THEN
BEGIN
IF .CSTMNT[A2VALFLG]
THEN
%(***IF RIGHT-HAND SIDE IS ALSO A SIMPLE VARIABLE***)%
SETREGFORA2VAL()
ELSE
BEGIN
TREEPTR_.RHNODE;
%(***IF THERE ARE NO REFERENCES TO THE LHS WITHIN THE EXPRESSION
ON THE RHS AND THE RHS IS NOT AN ARRAYREF,
AND THE NEG AND NOT FLAGS IN THE STATEMENT ARE BOTH 0,
ALLOCATE THE RHS TO BE COMPUTED TO THE
VARIABLE ON THE LHS*******)%
IF NOT .RHNODE[RESRFFLG] AND (NOT .RHNODE[OPRCLS] EQL ARRAYREF)
!IF LHS OF ASSIGNMENT STMNT IS A LOGICAL VARIABLE,
! AND IT IS IN COMMON OR EQUIVALENCED, THEN IT COULD
! BE NEEDED FOR EVALUATION OF RHS, SO PREVENT EARLY
! INITIALIZATION OF LHS TO -1
AND NOT(.LHNODE[VALTYPE] EQL LOGICAL
AND (.LHNODE[IDATTRIBUT(INEQV)] OR
.LHNODE[IDATTRIBUT(INCOM)]))
AND (NOT .LHNODE[OPRCLS] EQL REGCONTENTS)
AND (.CSTMNT[A2NGNTFLGS] EQL 0)
AND (.CSTMNT[A1NGNTFLGS] EQL 0)
THEN
BEGIN
ALCINTMP(.LHNODE,.STBSYR,.STRGCT);
IF .RHNODE[TARGTMEM] EQL .LHNODE
THEN
%(***IF COULD COMPUTE RHS DIRECTLY TO LHS***)%
BEGIN
CSTMNT[MEMCMPFLG]_1;
VARCLOBB(.LHNODE); !THE VAL OF THE VAR ON LHS HAS BEEN
! MODIFIED, CLEAR
! ANY BB ALLOC ENTRIES THAT REFER
! TO THAT VAR
IF .CSTMNT[SRCSAVREGFLG] !IF VAL OF LHS VAR IS USEFUL TO LEAVE
! IN A REG
AND .RHNODE[STOREFLG] !AND RHS WAS COMPUTED INTO A REG
! AND THEN STORED INTO LHS VAR
THEN
SAVEREG(.RHNODE[TARGTAC], !REMEMBER THAT LHS VAR
.LHNODE,0,.CSTMNT[SRCSONNXTUSE]); !IS IN THAT REG
RETURN;
END;
END
ELSE
%(***OTHERWISE, ALLOCATE THE RHS TO BE COMPUTED TO THE REG RA***)%
ALCINREG(.RA,.STBSYR,.STRGCT);
%(***DETERMINE REG FOR COMPUTATION OF THE STMNT***)%
IF .CSTMNT[ALCRETREGFLG]
THEN
%(***IF REG FOR COMPUTATION OF STMNT HAS ALREADY BEEN DETERMINED TO
BE THE FN-RETURN REG****)%
BEGIN END
ELSE
IF .RHNODE[INREGFLG]
THEN
%(***IF RHS IS COMPUTED INTO A REG, USE THAT REG AS REG FOR COMP FOR STMNT***)%
SETREGTORH
ELSE
%(***OTHERWISE USE SOME FREE REG***)%
USEAFREEREG()
END;
VARCLOBB(.LHNODE); !THE VAL OF THE VAR ON THE LHS HAS BEEN MODIFIED
! CLEAR ANY BB ALLOC ENTRIES THAT REFER TO IT
IF .CSTMNT[SRCSAVREGFLG] !IF VAL OF EITHER VAR ON LHS OR RHS IS OF FUTURE USE
! TO HAVE IN A REG
AND .CSTMNT[A1NGNTFLGS] EQL 0 !AND VAL WILL NOT BE STORED WITH "MOVNM"
AND NOT(.CSTMNT[A2IMMEDFLG] AND .CSTMNT[A2SAMEFLG]) !AND VAL WILL NOT BE STORED
! WITH "HRRZM" (DUE TO RHS BEING
! RIGHT HALF OF AOBJN WD)
THEN
SAVEREG(.CSTMNT[ASMNTREG], !REMEMBER THAT REG USED CONTAINS
.LHNODE, ! VAL OF VAR ON LHS
(IF .RHNODE[OPRCLS] EQL DATAOPR !AND IF RHS IS A VAR
AND .CSTMNT[A2NGNTFLGS] EQL 0 ! AND WAS NOT PICKED UP WITH "MOVN"
AND NOT (.CSTMNT[A1NEGFLG] AND
.LHNODE[VALTYPE] EQL DOUBLPREC) !AND DONT HAVE TO NEGATE A DP VAL (THERE IS NO MOVNM FOR DP)
THEN .RHNODE ! IT ALSO CONTAINS VAL OF VAR ON RHS
ELSE 0),
.CSTMNT[SRCSONNXTUSE]); ! AND THE NEXT USE OF THAT VAR WAS
! POINTED TO BY THE ASSIGNMNT STMNT
RETURN
END;
%(***IF LEFT-HAND SIDE IS NOT A SIMPLE VARIABLE, IT MUST BE AN ARRAY****)%
IF .LHNODE[OPRCLS] NEQ ARRAYREF
THEN CGERR();
%(****IF RIGHT HAND SIDE IS A SIMPLE VARIABLE, PERFORM REGISTER ALLOCATION FOR
LEFT HAND SIDE*******)%
IF .CSTMNT[A2VALFLG]
THEN
BEGIN
TREEPTR_.LHNODE;
ALCARRAY(.STBSYR,.STRGCT);
%(***GET REG FOR COMP FOR STMNT- DO NOT USE THE REG IN WHICH THE
INDEX INTO THE ARRAY WAS LEFT***)%
IF .LHNODE[TARGXF] NEQ 0
THEN
BEGIN
STBSYR_CLRBIT(.STBSYR,.LHNODE[TARGXF] );
IF .LHNODE[DBLFLG] !IF A 2 WD VAL IS TO BE STORED
THEN ! THEN IF THE INDEX WAS IN AN ODD REG, MUST NOT
STBSYR_CLRBIT(.STBSYR,.LHNODE[TARGXF]-1) !USE THE PRECEEDING EVEN
! REG (IF INDEX IN AN EVEN REG, THEN PRECEEDING REG
! IS ALREADY OUT OF THE SET BECAUSE IT IS ODD)
END;
RA_AFREEREG(.STBSYR,.CSTMNT[SRCSAVREGFLG],.LHNODE[DBLFLG]);
%(***DECIDE WHICH REG TO COMPUTE THE STMNT IN (GIVEN THAT A2VALFLG WAS SET)***)%
SETREGFORA2VAL();
VARCLOBB(.LHNODE); !IF THE ARRAY ON LHS IS IN COMMON OR EQV MUST
! ASSUME THAT VARS IN COMMON/EQV ARE CLOBBERED
IF .CSTMNT[SRCSAVREGFLG] !IF VAR ON RHS IS USEFUL TO LEAVE IN A REG
AND .CSTMNT[A2NGNTFLGS] EQL 0 ! AND WAS NOT PICKED UP WITH "MOVN"
AND .RHNODE[OPRCLS] EQL DATAOPR ! AND WAS NOT REPLACED BY A "REGCONTENTS"
AND NOT (.CSTMNT[A1NEGFLG] AND
.LHNODE[VALTYPE] EQL DOUBLPREC) !AND DONT HAVE TO NEGATE A DP VAL (THERE IS NO MOVNM FOR DP)
THEN SAVEREG(.CSTMNT[ASMNTREG], !REMEMBER TAHT REG USED FOR ASSIGNMNET
.RHNODE,0,.CSTMNT[SRCSONNXTUSE]); ! CONTAINS VAR ON RHS
RETURN;
END;
%(***IF COMPUTATION OF THE RHS WILL CLOBBER ALL REGISTERS AVAILABLE, THEN
SHOULD ALWAYS COMPUTE RHS BEFORE COMPUTING LHS, SO THAT
DO NOT NEED TO LEAVE PTR TO LHS IN A TEMPORARY***)%
IF .RHNODE[COMPLEXITY] GEQ .STRGCT
THEN CSTMNT[RVRSFLG]_1;
%(***IF RIGHT HAND SIDE IS COMPUTED BEFORE ADDRESS CALC FOR LEFT HAND SIDE****)%
IF .CSTMNT[RVRSFLG]
THEN
BEGIN
IF .LHNODE[COMPLEXITY] LSS .STRGCT
THEN
%(***IF ADDRESS CALCULATION CAN BE PERFORMED WITHOUT CLOBBERING
THE REG IN WHICH RIGHT-HAND-SIDE VAL IS LEFT***)%
BEGIN
TREEPTR_.RHNODE;
ALCINREG(.RA,.STBSYR,.STRGCT);
%(***DETERMINE WHICH (IF ANY) REG MUST BE SAVED WHILE COMPUTING
THE LHS BECAUSE IT HOLDS EITHER THE VAL OR A PTR TO THE
VAL OF THE RIGHT-HAND-SIDE***)%
RSV_RGTOSAVE(.RHNODE);
IF .RSV NEQ -1
THEN
BEGIN
%(***IF SOME REG MUST BE SAVED, ADJUST SET OF BUSY REGS***)%
STBSYR_CLRBIT(.STBSYR,.RSV);
STRGCT_.STRGCT-1;
END;
TREEPTR_.LHNODE;
ALCARRAY(.STBSYR,.STRGCT);
IF .RHNODE[INREGFLG]
THEN
SETREGTORH
ELSE
USEAFREEREG()
END
ELSE
BEGIN
TREEPTR_.RHNODE;
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
TREEPTR_.LHNODE;
ALCARRAY(.STBSYR,.STRGCT);
USEAFREEREG()
END;
END
ELSE
%(****IF ADDRESS CALC FOR LEFT-HAND SIDE IS PERFORMED BEFORE RIGHT-HAND SIDE IS COMPUTED***)%
BEGIN
%(***IF LH'S SUBSCRIPT IS A VARIABLE (LEAF) AND THE RH
CONTAINS SOME FUNCTION CALLS, THEN WE MUST CLEAR
THE MEMORY OF AC 1, SO ALCARRAY WON'T TRY TO
LEAVE THE SUBSCRIPT IN AC 1 IF ITS ALREADY
THERE (ALCARRAY NEVER LEAVES IT IN AC 0)***)%
IF .LHNODE[A2VALFLG] AND .RHNODE[FNCALLSFLG]
THEN REGCLOBB(1);
%(***CAN ASSUME THAT THE COMPUTATION OF RHS WILL NOT CLOBBER
THE PTR TO LHS****)%
%(***PERFORM REG ALLOC FOR COMPUTATION OF THE ADDRESS OF THE LHS***)%
TREEPTR_.LHNODE;
ALCARRAY(.STBSYR,.STRGCT);
%(***IF PTR TO LEFT-HAND-SIDE IS LEFT IN A REG, DO NOT USE THAT REG IN
COMPUTATION OF RIGHT-HAND-SIDE***)%
IF .LHNODE[TARGXF] NEQ 0
THEN
BEGIN
STBSYR_CLRBIT(.STBSYR,.LHNODE[TARGXF]);
IF .LHNODE[DBLFLG] !IF A 2 WD VAL IS TO BE STORED
THEN ! THEN IF THE INDEX WAS IN AN ODD REG, MUST NOT
STBSYR_CLRBIT(.STBSYR,.LHNODE[TARGXF]-1); !USE THE PRECEEDING EVEN
! REG (IF INDEX IN AN EVEN REG, THEN PRECEEDING REG
! IS ALREADY OUT OF THE SET BECAUSE IT IS ODD)
STRGCT_.STRGCT-1;
END;
%(***PERFORM REGISTER ALLOC FOR THE COMPUTATION OF THE RHS***)%
RA_AFREEREG(.STBSYR,FALSE,.LHNODE[DBLFLG]);
TREEPTR_.RHNODE;
ALCINREG(.RA,.STBSYR,.STRGCT);
IF .RHNODE[INREGFLG]
THEN
SETREGTORH
ELSE
USEAFREEREG()
END;
VARCLOBB(.LHNODE); !ASSUME VAL OF LHS IS CLOBBERED
END; !END OF ROUTINE "ALCASMNT"
GLOBAL ROUTINE ALCMEMCMP=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ASSIGNMENT STMNT TO BE
PERFORMED DIRECTLY TO MEMORY. IT IS ASSUMED THAT IF THE
OPERATION HAS 2 ARGS (IE IS EITHER A BOOLEAN OR ARITHMETIC) THEN ARG2 UNDER
THE RIGHT HAND SIDE IS EQUAL TO THE LEFT HAND SIDE.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE ASSIGNMENT STMNT.
***************************************************************************)%
BEGIN
EXTERNAL CLOBBNX;
OWN PEXPRNODE RHNODE:LHNODE:ARG1NODE:ARG2NODE;
EXTERNAL GETRGPAIR; !ROUTINE TO GET A PAIR OF FREE REGISTERS
OWN RA,RB;
EXTERNAL EXCHARGS;
RHNODE_.CSTMNT[RHEXP];
LHNODE_.CSTMNT[LHEXP];
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
RA_AFREEREG(.STBSYR,.CSTMNT[SRCSAVREGFLG],.LHNODE[DBLFLG]);
IF CLOBBNX(.RHNODE) !IF THIS OPERATION CLOBBERS THE REG AFTER THE
! REG ON WHICH IT IS PERFORMED (IE INTEGER DIVIDE)
AND .RHNODE[OPTOBOTHFLG] ! AND WE WILL BE GENERATING AN OP-TO-BOTH
! (RATHER THAN TO MEMORY - SINCE OPS TO MEM DONT CLOBBER THAT REG)
THEN
RA_GETRGPAIR(.RA,.STBSYR); !GET A REG TO USE THAT DOES NOT HAVE A USEFUL VAL
! IN THE REG FOLLOWING
%(***FOR P2PL1MUL,SQUARE, AND CUBE - THE ARG THAT IS EQL TO THE LEFT HAND
SIDE IS ARG1 (AND THIS IS THE ONLY ARG). HENCE DONT HAVE TO
WORRY ABOUT ALLOCATING THE OTHER ARG***)%
IF .RHNODE[OPRCLS] EQL SPECOP
THEN
BEGIN
RA_RGTOU1(.RHNODE,.RHNODE[ARG1PTR],.RA,.STBSYR);
SETTAC(.RHNODE,.RA)
END
%(***FOR ARITHMETIC AND BOOLEAN OPERATORS***********)%
ELSE
BEGIN
%(***FOR ARITH OPS, CANNOT HAVE NEG ON ARG2. REMOVE A2NEGFLG BY
A+(-B)=A-B, A*(-B)=-A*B, A/(-B)=(-A)/B
SINCE REMOVING NEG FROM ARG2 MAY CHANGE "A1NEGFLG" MUST DO IT BEFORE
DECIDE WHETHER CAN USE ARG1 DIRECTLY FROM A GIVEN REG.***)%
IF .RHNODE[A2NEGFLG] AND .RHNODE[OPRCLS] EQL ARITHMETIC
THEN
BEGIN
IF ADDORSUB(RHNODE) !MAKE ADD INTO SUB, SUB INTO ADD
THEN CMPLSP(RHNODE)
ELSE IF MULORDIV(RHNODE) !FOR MUL, DIV
THEN RHNODE[A1NEGFLG]_NOT.RHNODE[A1NEGFLG] !REVERSE THE NEG ON ARG1
ELSE CGERR(); !OPS TO MEM CANNOT BE EXPONEN
RHNODE[A2NEGFLG]_0;
END;
%(****PERFORM REGISTER ALLOCATION FOR ARG1 UNDER THE RIGHT HAND SIDE****)%
IF .RHNODE[A1VALFLG]
THEN
BEGIN
%(***IF ARG1 IS A REGCONTENTS NODE THEN
1. IF ONLY WANT TO USE THE RIGHT HALF OF TH REG
THEN MUST MOVE IT INTO RA
2. IF THE OPERATION CLOBBERS THE REG USED
THEN MUST MOVE IT TO RA
3. OTHERWISE, USE THAT REGISTER AS REGFORCOMP
FOR RHNODE
********)%
IF .ARG1NODE[OPRCLS] EQL REGCONTENTS AND NOT .RHNODE[A1IMMEDFLG]
AND NOT .RHNODE[A1NEGFLG] AND NOT .RHNODE[A1NOTFLG]
!(DOUBLE-PREC AND COMPLEX OPS TO MEMORY CLOBBER THE REG)
AND NOT .RHNODE[DBLFLG]
THEN
BEGIN
RHNODE[TARGTAC]_.ARG1NODE[TARGTAC];
RHNODE[A1SAMEFLG]_1;
END
ELSE
IF (RB_REGCONTAINING(.ARG1NODE)) GEQ 0 !IF ARG1 WAS LEFT IN A REG
THEN ! EARLIER IN THIS BB
BEGIN
IF .RHNODE[A1NGNTFLGS] NEQ 0 !IF ARG1 MUST BE NEGATED/COMPLEMENTED
AND NOT BITSET (.STBSYR,.RB) ! AND WE CANNOT CLOBBER RB
THEN ! MUST NOT USE RB
SETTAC(.RHNODE,.RA) !USE RA
ELSE
BEGIN
SETTAC(.RHNODE,.RB); !USE THAT REG FOR THIS OP TO MEMORY
RHNODE[A1SAMEFLG]_1; !DONT RELOAD THE REG
END
END
%(***IF ARG1 IS A SCALAR, USE RA***)%
ELSE
SETTAC(.RHNODE,.RA);
IF .RHNODE[SAVREGFLG] !IF VAL OF ARG1 WILL BE USEFUL TO HAVE IN A REG LATER
AND .ARG1NODE[OPRCLS] EQL DATAOPR
AND NOT .RHNODE[DBLFLG] ! AND THE OPERATION IS NOT DP OR COMPLEX (WHICH
! OPS CLOBBER THE REG USED FOR THE OP TO MEMORY)
AND NOT .RHNODE[OPTOBOTHFLG] !AND WE HAVE NOT ALREADY DECIDED
! TO PERFORM THE OPERATION TO BOTH
! TEST FOR NOT ON PARENT NODE TOO!
AND NOT .RHNODE[A1NOTFLG]
AND NOT .RHNODE[A1NEGFLG] !AND ARG1 WAS NOT PICKED UP BY "MOVN"
THEN SAVEREG(.RHNODE[TARGTAC], !REMEMBER THAT THE REG USED
.ARG1NODE,0,.RHNODE[SONNXTUSE]); !CONTAINS VAL OF ARG1
END
ELSE
BEGIN
TREEPTR_.RHNODE[ARG1PTR];
ALCINREG(.RA,.STBSYR,.STRGCT);
IF .RHNODE[ALCRETREGFLG]
THEN
%(***IF WE DECIDED ON THE COMPLEXITY-PASS TO USE THE FN-RETURN REGISTER
FOR COMPUTATION OF RHNODE*****)%
BEGIN END
ELSE
IF .ARG1NODE[INREGFLG] AND NOT .ARG1NODE[ALCRETREGFLG]
THEN
%(***IF THE LEFT-ARGUMENT OF RHNODE HAD ITS VAL LEFT IN A REG****)%
BEGIN
RHNODE[TARGTAC]_.ARG1NODE[TARGTAC];
RHNODE[A1SAMEFLG]_1;
END
ELSE
%(***OTHERWISE USE RA TO COMPUTE RHNODE****)%
BEGIN
RA_REGTOUSE(.RHNODE,.RHNODE[ARG1PTR],.RHNODE[ARG2PTR],.RA,.STBSYR);
SETTAC(.RHNODE,.RA)
END
END;
END;
%(***IF THIS OPERATION IS MOST OPTIMALLY PERFORMED FROM A REG
THAT WE CANNOT CLOBBER, THEN WE CANNOT DO IT "TO BOTH"***)%
IF .RHNODE[OPTOBOTHFLG]
THEN
BEGIN
IF NOT BITSET(.STBSYR,.RHNODE[TARGTAC]) !IF THE REG USED CANNOT BE CLOBBERED
OR
(CLOBBNX(.RHNODE) !OR IF THIS OPERATION WILL CLOBBER
! THE REG FOLLOWING THE REG USED
AND NOT BITSET(.STBSYR,.RHNODE[TARGTAC]+1) ! AND THAT REG CANNOT BE CLOBBERED
)
THEN
(CSTMNT[OPTOBOTHFLG]_0;RHNODE[OPTOBOTHFLG]_0); !TURN OFF FLAGS FOR
! "PERFORM OP TO BOTH"
END;
%(***IF THE ELEMENT ON THE LHS (WHICH IS ALSO ARG2 UNDER THE RHS) IS
AN ARRAY REF, PERFORM ALLOC FOR THOSE 2 NODES***)%
IF NOT .CSTMNT[A1VALFLG]
THEN
BEGIN
OWN BSYRG1;
RA_.RHNODE[TARGTAC];
BSYRG1_CLRBIT(.STBSYR,.RA); !WHEN COMPUTING THE SS DO NOT USE
! THE REG USED FOR THE OPERATION TO MEM
TREEPTR_.LHNODE;
IF .TREEPTR[OPRCLS] NEQ ARRAYREF THEN CGERR();
ALCARRAY(.BSYRG1,.STRGCT-1);
TREEPTR_(IF .RHNODE[OPRCLS] EQL SPECOP THEN .RHNODE[ARG1PTR] ELSE .RHNODE[ARG2PTR]);
IF .TREEPTR[OPRCLS] NEQ ARRAYREF THEN CGERR();
ALCARRAY(.BSYRG1,.STRGCT-1);
%(***THE FIRST COMPUTATION TO PERFORM SHOULD ALWAYS BE
THAT OF ARG1 UNDER THE RIGHT-HAND SIDE***)%
CSTMNT[RVRSFLG]_1;
RHNODE[RVRSFLG]_0;
END;
RHNODE[A2SAMEFLG]_1; !WILL COMPUTE INTO THE LOC CONTAING ARG2
RHNODE[MEMCMPFLG]_1;
VARCLOBB(.LHNODE); !THE VAL OF THE VAR ON THE LHS OF THIS ASSIGNMENT STMNT
! HAS NOW BEEN MODIFIED. MUST CLEAR ANY BB ALLOC
! TABLE ENTRIES THAT REFER TO THAT VAR
IF .CSTMNT[SRCSAVREGFLG] !IF THE LHS OF THIS ASSIGNMENT WILL BE
! USEFUL TO HAVE IN A REG LATER
AND .CSTMNT[OPTOBOTHFLG] ! AND THIS OPERATION IS PERFORMED "TO BOTH"
THEN SAVEREG(.RHNODE[TARGTAC], !THEN REMEMBER THAT THE REG USED FOR THIS OP
.LHNODE,0,.CSTMNT[SRCSONNXTUSE]); ! CONTAINS THE VAL OF THE VAR ON THE LHS
END; !END OF ROUTINE ALCMEMCMP
GLOBAL ROUTINE ORDERMEMCMP=
%(***************************************************************************
ROUTINE TO ORDER ARGS OF AN ARITH OR BOOLEAN OP TO MEMORY SO THAT
ARG2 IS IDENTICAL TO THE LHS OF THE ASSIGNMENT STMNT
BE PERFORMED TO MEMORY.
***************************************************************************)%
BEGIN
OWN PEXPRNODE RHNODE:LHNODE:ARG1NODE:ARG2NODE;
EXTERNAL EXCHARGS; !ROUTINE TO EXCHANGE ARG1 AND ARG2 OF AN OPERATOR
! IF POSSIBLE
ROUTINE ARREQLLH(NODE)=
%(***TO DETERMINE IF 'NODE' IS AN ARRAYREF THAT IS IDENTICAL TO AN ARRAYREF
ON THE LEFT-HAND-SIDE OF THIS ASSIGNMENT STMNT***)%
BEGIN
MAP PEXPRNODE NODE;
IF .NODE[ARGWD] EQL .LHNODE[ARGWD] !IF ARRAY NAME AND VARIABLE PART
! OF SS EXPR ARE IDENTICAL
THEN
RETURN (.NODE[TARGET] EQL .LHNODE[TARGET] AND .NODE[OPRCLS] EQL ARRAYREF)
ELSE RETURN FALSE
END;
RHNODE_.CSTMNT[RHEXP];
LHNODE_.CSTMNT[LHEXP];
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
%(***MUST BE SURE THAT THE ARG UNDER RHNODE WHICH IS EQUAL TO THE LEFT-HAND SIDE
IS THE 2ND ARG (ARGS MAY HAVE BEEN REVERSED SOMETIME SINCE P2SKEL)***)%
IF .CSTMNT[A1VALFLG]
THEN
BEGIN
IF .ARG2NODE NEQ .LHNODE
THEN
BEGIN
IF .ARG1NODE NEQ .LHNODE THEN CGERR();
IF NOT EXCHARGS(.RHNODE) THEN CGERR();
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
END
END
ELSE
%(***FOR THE LEFT HAND SIDE AN ARRAYREF***)%
IF .LHNODE[OPRCLS] EQL ARRAYREF
THEN
BEGIN
IF NOT ARREQLLH(.ARG2NODE)
THEN
%(***IF ARG2 IS NOT EQUAL TO LHS***)%
BEGIN
%(***IF NEITHER ARG UNDER RHNODE WAS EQL TO LHNODE, SHOULD
NOT HAVE CALLED THIS ROUTINE***)%
IF NOT ARREQLLH(.ARG1NODE) THEN CGERR();
%(***IF ARG1 AND ARG2 CANNOT BE SWAPPED, THEN COULD NEVER
HAVE HAD THEM REVERSED EARLIER(IN P2SKEL WHEN DETECTED
THIS COMP TO MEMORY) - HENCE HAVE A COMPILER BUG***)%
IF NOT EXCHARGS(.RHNODE) THEN CGERR();
%(***HAVE NOW SWITCHED THE ARGS (EXCHARGS DOES THIS)***)%
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
END
END;
END; !END OF ROUTINE ORDERMEMCMP
GLOBAL ROUTINE ALCASSI=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ASSIGN STATEMENT.
IF VAR ASSIGNED TO IS AN ARRAYREF, MUST PERFORM ALLOC FOR IT.
THE "ASSIGN" OPERATION IS ALWAYS PERFORMED IN REGISTER 1.
***************************************************************************)%
BEGIN
TREEPTR_.CSTMNT[ASISYM];
IF .TREEPTR[OPRCLS] EQL ARRAYREF
THEN
ALCARRAY(.STBSYR,.STRGCT);
REGCLOBB(1); !THE CONTENTS OF REG 1 WILL BE CLOBBERED BY EVAL
! OF THIS STMNT. CLEAR BB ALLOC TABLE ENTRY FOR REG 1
VARCLOBB(.CSTMNT[ASISYM]); !THE VARIABLE ASSIGNED HAS HAD ITS VAL MODIFIED.
! CLEAR ANY BB ALLOC ENTRIES THAT REFER TO THAT VAR
END;
GLOBAL ROUTINE ALCCALL=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR A CALL STMNT.
***************************************************************************)%
BEGIN
EXTERNAL CLOBBREGS; !WD CONTAINING BIT PTN FOR REGS CLOBBERED
! BY THIS ROUTINE
EXTERNAL ALCFNARGS;
REGISTER PEXPRNODE SYMPTR; !PTR TO SYMBOL TABLE ENTRY FOR THE
! SUBROUTINE NAME
ALCCMNSB(); !PERFORM ALLOCATION FOR ANY COMMON SUBS
IF .CSTMNT[CALLIST] NEQ 0
THEN
BEGIN
TREEPTR_.CSTMNT[CALLIST];
ALCFNARGS(.STBSYR,.STRGCT,FALSE);
END;
%(**THE SUBROUTINE CALLED CAN POTENTIALLY CLOBBER ALL THE REGS,
(UNLESS IT'S A LIBRARY SUBROUTINE SUCH AS "ADJ1.")
HENCE IF THIS IS A FN IT WILL HAVE TO SAVE/RESTORE THEM ALL**)%
SYMPTR_.CSTMNT[CALSYM]; !SYM TABLE ENTRY FOR ROUTINE NAME
IF NOT .SYMPTR[IDLIBFNFLG] !IF THE ROUTINE IS NOT A LIBRARY ROUTINE
THEN
CLOBBREGS_.CLOBBREGS OR #177760000000 !SET BITS FOR REGS 2-15
END;
GLOBAL ROUTINE ALCAGO=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ASSIGNED GOTO
(NOTE THAT THE ASSIGNED VAL MAY BE AN ARRAYREF THAT REQUIRES CALCULATION)
THE ACTUAL TESTING OF THE VAL WILL ALWAYS BE PERFORMED IN REG 1.
CALLED WITH THE GLOBALS
CSTMNT - PTR TO THE STMNT
STBSYR - HAS A BIT SET FOR EACH REG AVAILABLE FOR USE IN COMPUTING
THIS STMNT
STRGCT - CT OF REGS AVAILABLE FOR USE IN COMPUTING THIS STMNT
***************************************************************************)%
BEGIN
%(***PERFORM REGISTER ALLOCATION FOR ANY COMMON SUBEXPRS UNDER THIS STATEMENT***)%
ALCCMNSB();
%(***PERFORM REG ALLOC FOR ACCESSING THE ASSIGNED VAR***)%
TREEPTR_.CSTMNT[AGOTOLBL];
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
ALCINREG(AFREEREG(.STBSYR,FALSE,FALSE),.STBSYR,.STRGCT);
REGCLOBB(1); !THE CONTENTS OF REG 1 ARE CLOBBERED BY EVAL OF THIS
! STMNT. CLEAR BB ALLOC ENTRIES FOR REG 1
END;
GLOBAL ROUTINE ALCCGO=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR A COMPUTED GOTO.
PERFORMS REGISTER-ALLOCATION FOR THE COMPUTATION OF THE COMPUTED
EXPRESSION. THAT VAL WILL ALWAYS BE MOVED TO REG #1 (AS PART OF A SKIP
OPERATION THAT TESTS ITS RANGE) FOR EXCUTION OF THE GOTO
CALLED WITH THE GLOBALS
CSTMNT - PTR TO THE STMNT
STBSYR - HAS A BIT SET FOR EACH REG AVAILABLE FOR USE IN COMPUTING
THIS STMNT
STRGCT - CT OF REGS AVAILABLE FOR USE IN COMPUTING THIS STMNT
***************************************************************************)%
BEGIN
%(***PERFORM REGISTER ALLOCATION FOR ANY COMMON SUBEXPRS UNDER THIS STATEMENT***)%
ALCCMNSB();
%(***PERFORM REGISTER ALLOCATION FOR COMPUTATION OF THE COMPUTED EXPR***)%
TREEPTR_.CSTMNT[CGOTOLBL];
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
ALCINREG(AFREEREG(.STBSYR,FALSE,FALSE),.STBSYR,.STRGCT);
REGCLOBB(1); !THE CONTENTS OF REG 1 ARE CLOBBERED BY EVAL OF THIS
! STMNT. CLEAR BB ALLOC ENTRIES FOR REG 1
END;
GLOBAL ROUTINE ALCLIF=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR A LOGICAL IF STATEMNT.
CALLED WITH THE GLOBALS
CSTMNT - PTR TO THE STMNT
STBSYR - HAS A BIT SET FOR EACH REG AVAILABLE FOR USE IN COMPUTING
THIS STMNT
STRGCT - CT OF REGS AVAILABLE FOR USE IN COMPUTING THIS STMNT
***************************************************************************)%
BEGIN
EXTERNAL ALCRL1,ALCCNT;
OWN PEXPRNODE CONDEXPR;
OWN BASE SAVSTMNT;
OWN SAVBSYR,SAVRCT;
SAVBSYR_.STBSYR;
SAVRCT_.STRGCT;
CONDEXPR_.CSTMNT[LIFEXPR];
%(***IF THIS STATEMENT IS DOUBLE-PREC, ADJUST SET OF BUSY REGS SO
THAT ONLY EVEN REGS WILL BE ALLOCATED****)%
IF .CONDEXPR[DBLFLG]
THEN
BEGIN
STBSYR_DPBSYREGS(.STBSYR);
STRGCT_ONESCOUNT(.STBSYR);
DBLMODE_TRUE;
END
ELSE
DBLMODE_FALSE;
%(***PERFORM REGISTER ALLOCATION FOR ANY COMMON SUBEXPRS UNDER THIS STMNT***)%
ALCCMNSB();
%(***PERFORM REGISTER ALLOCATION FOR THE CONDITIONAL EXPRESSION***)%
TREEPTR_.CONDEXPR;
%(***IF THE EXPRESSION IS OF TYPE CONTROL, NEED NEVER COMPUTE A VALUE FOR IT***)%
IF .CONDEXPR[VALTYPE] EQL CONTROL
THEN
BEGIN
IF .CONDEXPR[OPRCLS] EQL RELATIONAL !FOR A RELATIONAL
THEN ALCRL1(.STBSYR,.STRGCT)
ELSE
IF .CONDEXPR[OPRCLS] EQL BOOLEAN !FOR A BOOLEAN
THEN
BEGIN
NOBBREGSLOAD_TRUE; !CANNOT ASSUME THAT ALL CODE FOR A CONTROL
! BOOLEAN WILL BE EXECUTED - SO SET FLAG
! TO MAKE NO ASSUMPTIONS ABOUT REGS BEING LOADED
ALCCNT(.STBSYR,.STRGCT);
NOBBREGSLOAD_FALSE; !CLEAR FLAG
END
ELSE CGERR(); !A CONTROL-TYPE EXPR MUST BE BOOLEAN OR RELATIONAL
END
%(***OTHERWISE WILL HAVE TO COMPUTE THE VAL AND TEST IT***)%
ELSE
BEGIN
IF .CONDEXPR[OPRCLS] EQL BOOLEAN !IF THE CONDITIONAL EXPR IS A BOOLEAN
THEN
BEGIN
%(***WHEN BOOLEANS IN WHICH ARG1 IS A MASK AND ARG2 IS OF TYPE CONTROL
ARE USED IN A LOGICAL IF - THE CODE GENERATED WILL TEST THE
THE VAL OF THE MASK AND NOT EXECUTE THE CONTROL PART
IF ITS NOT NECESSARY
*****)%
OWN PEXPRNODE ARG2NODE;
ARG2NODE_.CONDEXPR[ARG2PTR];
IF .ARG2NODE[VALTYPE] EQL CONTROL !AND THE 1ST TERM OF THE BOOLEAN
! IS A MASK AND THE 2ND IS OF TYPE CONTROL
THEN
NOBBREGSLOAD_TRUE !DONT MAKE ASSUMPTION THAT ALL
! CODE FOR THIS BOOLEAN IS ALWAYS EXECUTED
END;
ALCINREG(AFREEREG(.STBSYR,FALSE,FALSE),.STBSYR,.STRGCT);
END;
%(***PERFORM REGISTER ALLOCATION FOR THE SUBSTATEMENT****)%
SAVSTMNT_.CSTMNT;
STBSYR_.SAVBSYR;
STRGCT_.SAVRCT;
CSTMNT_.CSTMNT[LIFSTATE];
NOBBREGSLOAD_TRUE; !DO NOT ASSUME THAT ANY REGS INITIALIZED BY EVALUATION
! OF THE SUBSTATEMENT CAN BE USED LATER (SINCE THE SUBSTATEMENT
! IS NOT ALWAYS EVALUATED)
ALCSTMN(); !PERFORM ALLOCATION FOR EVALUATION OF THE SUBSTATEMENT
NOBBREGSLOAD_FALSE; !RESET FLAG SO THAT WILL ONCE AGAIN ASSUME THAT
! CODE IS EXECUTED (IF THIS BASIC BLOCK IS EXECUTED)
CSTMNT_.SAVSTMNT;
END;
GLOBAL ROUTINE ALCAIF=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ARITHMETIC IF.
CALLED WITH THE GLOBALS
CSTMNT - PTR TO THE STATEMENT
STBSYR - HAS A BIT SET FOR EACH REG AVAILABLE FOR USE
IN COMPUTING THIS STMNT
STRGCT - CT OF REGS AVAILABLE
***************************************************************************)%
BEGIN
OWN RA,RB;
TREEPTR_.CSTMNT[AIFEXPR];
%(*****IF THE VALUE IS DOUBLE-WD, ADJUST THE SET OF REGS SO THAT ONLY EVEN
REGS WILL BE ALLOCATED*****)%
IF .TREEPTR[DBLFLG]
THEN
BEGIN
STBSYR_DPBSYREGS(.STBSYR);
STRGCT_ONESCOUNT(.STBSYR);
DBLMODE_TRUE;
END
ELSE
DBLMODE_FALSE;
%(***PERFORM REGISTER ALLOCATION FOR ANY COMMON SUBEXPRS UNDER THIS STMNT***)%
IF .CSTMNT[SRCCOMNSUB] NEQ 0 THEN ALCCMNSB();
%(***PERFORM REGISTER ALLOCATION FOR THE COMPUTATION OF THE ARITHMETIC EXPRESSION***)%
TREEPTR_.CSTMNT[AIFEXPR];
RA_AFREEREG(.STBSYR,FALSE,.TREEPTR[DBLFLG]);
ALCINREG(.RA,.STBSYR,.STRGCT);
%(***DECIDE WHAT REG TO USE WHEN TESTING THE VALUE OF THE EXPR***)%
TREEPTR_.CSTMNT[AIFEXPR];
IF .TREEPTR[INREGFLG]
THEN
BEGIN
CSTMNT[AIFREG]_.TREEPTR[TARGTAC];
CSTMNT[A1SAMEFLG]_1;
END
ELSE
IF (RB_REGCONTAINING(.CSTMNT[AIFEXPR])) GEQ 0 !IF VAR TO BE TESTED WAS LEFT IN A REG
THEN
BEGIN
CSTMNT[AIFREG]_.RB; !USE THAT REG
CSTMNT[A1SAMEFLG]_1; !DONT RELOAD THE REG
END
ELSE
BEGIN
%(**PICK A REG TO LOAD THE VAL TO BE TESTED - SINCE THE REG
GETS LOADED WITH A SKIP INSTR, DO NOT ALLOW REG 0 TO BE USED**)%
RA_RGTOU1(.CSTMNT,.TREEPTR,.RA,CLRBIT(.STBSYR,REG0));
CSTMNT[AIFREG]_.RA;
REGCLOBB(.CSTMNT[AIFREG]); !THE PREVIOUS CONTENTS OF THE
! REG ASSIGNED WILL BE CLOBBERED.
! CLEAR BB ALLOC ENTRIES FOR THAT REG
END;
END;
GLOBAL ROUTINE ALCDECENC=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR ENCODE/DECODE STMNTS.
***************************************************************************)%
BEGIN
OWN RA;
EXTERNAL ALCARRAY,TREEPTR;
OWN PEXPRNODE ENCVAR;
OWN PEXPRNODE ENCCT; !EXPRESSION FOR CHAR CT
ENCVAR_.CSTMNT[IOVAR];
ENCCT_.CSTMNT[IOCNT];
%(***IF THE CHARACTER CT IS AN EXPRESSION, PERFORM REGISTER ALLOC FOR
ITS CALCULATION***)%
IF .ENCCT[OPRCLS] NEQ DATAOPR
THEN
BEGIN
TREEPTR_.ENCCT;
ALCINREG(AFREEREG(.STBSYR,FALSE,FALSE),.STBSYR,.STRGCT);
%(***IF SOME REGISTER MUST BE PRESERVED IN ORDER TO PRESERVE THE
VAL OF THE COUNT, DONT WANT TO USE THAT REG IN CALCULATING
THE ARRAY ADDRESS***)%
IF (RA_RGTOSAVE(.ENCCT)) NEQ -1
THEN (STBSYR_CLRBIT(.STBSYR,.RA); STRGCT_.STRGCT-1);
END;
%(***IF THE ENCODE-ARRAY IS ACTUALLY AN "ARRAYREF" NODE (IE INCLUDES AN
OFFSET WITHIN THE ARRAY), PERFORM REGISTER ALLOCATION FOR THE ADDRESS
CALCULATION***)%
IF .ENCVAR[OPRCLS] EQL ARRAYREF
THEN
BEGIN
TREEPTR_.ENCVAR;
ALCARRAY(.STBSYR,.STRGCT);
END;
ALCIOLST(); !PERFORM REG ALLOC FOR THE IOLIST
IF .CSTMNT[SRCID] EQL ENCOID !FOR ENCODE STMNTS MUST ASSUME THAT
THEN VARCLOBB(.ENCVAR); ! THE ARRAY BEING ENCODED INTO (AND ANY VARS POTENTIALLY EQUIVALENCED
! TO IT) HAS IT CONTENTS MODIFIED
END; !END OF ALCDECENC
GLOBAL ROUTINE ALCOPEN=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN OPEN STMNT -
FOR THE CALCULATION OF ARGS THAT ARE EXPRESSIONS (EG ARRAYREFS
WITH EXPRESSIONS IN THE SUBSCRIPTS)
***************************************************************************)%
BEGIN
EXTERNAL ALCTARY;
REGISTER OPENLIST ARVALLST;
ARVALLST_.CSTMNT[OPLST]; !LIST OF ARGS UNDER THE OPEN
%(**WALK THRU THE LIST OF ARGS, PERFORM REGISTER ALLOC FOR THE CALC OF ANY ARG
THAT IS NOT A VAR OR CONST***)%
INCR I FROM 0 TO (.CSTMNT[OPSIZ]-1)
DO
BEGIN
TREEPTR_.ARVALLST[.I,OPENLPTR]; !EXPRESSION NODE FOR THE VAL OF THE ITH ARG
IF .TREEPTR EQL 0 !IF HAVE A NULL VAL FOR "DIALOG", DO NOTHING
THEN BEGIN END
ELSE
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
BEGIN
!BE SURE TO HANDLE ARRAY FOR ASSOCIATE VARIABLE CORRECTLY HERE
! SO THAT THE ADDRESS IS SET UP RATHER THAN THE VALUE IN THE ARRAY ELEMENT
IF .TREEPTR[OPRCLS] EQL ARRAYREF !FOR ARRAY ELEMENT
THEN ARVALLST[.I,OPENLPTR]_ !LINK IN PTR TO STORECLS NODE
(IF .ARVALLST[.I,OPENLCODE] EQL OPNCASSOCIATE
THEN ALCTARY(.STBSYR,.STRGCT) !HERE IS THE CHANGE
ELSE ALCTVARR(.STBSYR,.STRGCT))
ELSE ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
END;
END;
END; !END OF "ALCOPEN"
GLOBAL ROUTINE ALCCMNSB=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR ALL COMMON SUBEXPRS UNDER
THE STATEMENT "CSTMNT".
DEPENDING ON THE NUMBER OF REGS NECESSARY TO COMPUTE THE STATEMENT
AND THE NUMBER OF REGS AVAILABLE (WHICH IS INDICATED BY THE GLOBAL "STRGCT",
LEAVES AS MANY COMMON SUBEXPRS AS POSSIBLE IN REGISTERS.
***************************************************************************)%
BEGIN
EXTERNAL PAIRMODE; !THIS GLOBAL IS SET TO TRUE IFF THIS STMNT USES ANY REG PAIRS
EXTERNAL FREEPAIRS; !ROUTINE TO COUNT THE NUMBER OF EVEN-ODD REG PAIRS INDICATED
! TO BE FREE BY A BIT PATTERN IN
! WHICH 0'S REPRESENT BUSY REGS, 1'S REPRESENT FREE REGS
OWN RA,RB;
OWN PEXPRNODE CCMNSUB:ARGNODE;
OWN BASE CCSTMNT; ! SAVE CSTMNT
OWN BSYRG1,REGCT1;
OWN REGSNEEDED; !NUMBER OF REGISTERS NEEDED (EXCEPT FOR COMMON SUBEXPRS)
! FOR COMPUTATION OF THIS STMNT
OWN PAIRSNEEDED; !FOR STMNTS THAT REQUIRE REG PAIRS, MAX NUMBER OF PAIRS NEEDED
OWN FREERGPAIRS; !NUMBER OF REG PAIRS FREE
CCMNSUB_.CSTMNT[SRCCOMNSUB];
CCSTMNT_.CSTMNT; ! SAVE CSTMNT FOR ALC TO 0 CHECK
REGSNEEDED_.CSTMNT[SRCCMPLX]; !NUMBER OF REGS NEEDED FOR THIS STMNT
PAIRSNEEDED_(.CSTMNT[SRCCMPLX]+1)/2; !MAX NUMBER OF PAIRS NEEDED
%(**WALK THRU ALL COMMON SUBS ON THIS STMNT***)%
UNTIL .CCMNSUB EQL 0
DO
BEGIN
ARGNODE_.CCMNSUB[ARG2PTR];
TREEPTR_.ARGNODE;
%(***IF THIS COMMON SUBEXPR IS DOUBLE-PREC AND THE STATEMENT IS NOT,
THEN MUST ADJUST THE SET OF AVAILABLE REGS TO INCLUDE ONLY EVEN REGS***)%
IF .ARGNODE[DBLFLG] AND NOT .DBLMODE
THEN
BEGIN
BSYRG1_DPBSYREGS(.STBSYR);
REGCT1_ONESCOUNT(.BSYRG1);
END
ELSE
BEGIN
BSYRG1_.STBSYR;
REGCT1_.STRGCT;
END;
%(***IF THIS COMMON SUB WILL BE USED AS A SS, DONT USE REG 0 FOR IT**)%
IF .CCMNSUB[CSSSFLG]
THEN
BEGIN
IF BITSET(.BSYRG1,0) THEN
(REGCT1_.REGCT1-1; BSYRG1_CLRBIT(.BSYRG1,0))
END;
%(***DETERMINE HOW MANY REG PAIRS ARE NOW AVAILABLE**)%
FREERGPAIRS_
IF .DBLMODE OR .ARGNODE[DBLFLG] !IF BSYRG1 IS ALREADY IN TERMS OF PAIRS
THEN .REGCT1
ELSE FREEPAIRS(.STBSYR);
%(***IF THERE ARE ENOUGH REGISTERS FREE SO THAT THIS THIS EXPRESSION
CAN BE LEFT IN A REG WHILE CALCULATING THE WHOLE STATEMENT,
LEAVE THIS EXPR IN A REG.
OTHERWISE LEAVE IT IN A TEMPORARY.
********)%
IF (NOT .PAIRMODE !WHEN THIS STMNT NEEDS NO ADJACENT PAIRS
AND .STRGCT GTR .REGSNEEDED+1) !NUMBER OF REGS LEFT SHOULD BE
! GREATER THAN 1 MORE THAN NUMBER NEEDED
OR
(.FREERGPAIRS GTR .PAIRSNEEDED+1) !IF STMNT WILL NEED PAIRS, SHOULD
! HAVE AT LEAST 1 EXTRA PAIR BEFORE RISK
! USING UP A PAIR
OR
(.CCMNSUB[CSSSFLG] !IF THIS CSB IS USED AS A SUBSCRIPT
AND .FREERGPAIRS GTR 2) !THEN PUT IT IN A REG AS LONG AS
! 2 PAIRS CAN BE LEFT
THEN
BEGIN
RA_AFREEREG(.BSYRG1,.CCMNSUB[SAVREGFLG],.CCMNSUB[DBLFLG]);
IF NOT .CCMNSUB[A2VALFLG]
THEN
ALCINREG(.RA,.BSYRG1,.REGCT1);
%(***IF THE COMMON SUB WAS COMPUTED INTO A REG WHERE IT CAN
BE LEFT - LEAVE IT THERE***)%
IF .ARGNODE[INREGFLG] AND NOT .ARGNODE[ALCRETREGFLG]
!IF THE COMMON SUB IS THE RIGHT HALF OF AN AOBJN WD
! AND IS USED IN A CONTEXT THAT REQUIRES A FULL WD,
! CANNOT USE THE AOBJN REG
AND NOT (.CCMNSUB[A2IMMEDFLG] AND .CCMNSUB[CSFULLWDFLG])
THEN
BEGIN
CCMNSUB[TARGTAC]_.ARGNODE[TARGTAC];
CCMNSUB[TARGADDR]_.CCMNSUB[TARGTAC];
CCMNSUB[A2SAMEFLG]_1;
END
ELSE
IF (RB_REGCONTAINING(.ARGNODE)) GEQ 0 !IF ARG IS A VAR WHOSE VAL WAS LEFT IN A REG
AND ! IF IT'S AN ASSIGNMENT STATEMENT
(IF .CCSTMNT[SRCID] EQL ASGNID AND .CCSTMNT[OPRCLS] EQL STATEMENT
THEN ! IF THE LEFT HALF IS A REGCONTENTS
BEGIN ! NODE TO 0
LOCAL PEXPRNODE T1;
T1_.CCSTMNT[LHEXP];
IF .T1[OPRCLS] EQL REGCONTENTS AND .RB EQL 0
THEN FALSE ! WE CAN'T USE ZERO
ELSE TRUE ! ANYTHING BUT 0
END
ELSE TRUE)
AND NOT ((.RB EQL RETREG ! THIS IS NOT 0
OR .RB EQL (RETREG+1)) ! OR 1
AND .CSTMNT[FNCALLSFLG]) ! WHEN THERE IS A FUNCTION CALL
! UNDER THIS NODE
AND .CCMNSUB[A2NGNTFLGS] EQL 0 ! AND ARG NEED NOT BE NEGATED
AND NOT(.RB EQL 0 AND .CCMNSUB[CSSSFLG]) !AND DO NOT HAVE A VAR WHICH WILL
! BE USED AS A SS IN REG 0
THEN
BEGIN
CCMNSUB[TARGTAC]_.RB; !THEN USE THAT REG
CCMNSUB[TARGADDR]_.RB;
CCMNSUB[A2SAMEFLG]_1; !DONT RELOAD THE REG
END
ELSE
BEGIN
RA_RGTOU1(.CCMNSUB,.ARGNODE,.RA,.BSYRG1);
SETTARGINREG(.CCMNSUB,.RA)
END;
CCMNSUB[INREGFLG]_1;
RA_.CCMNSUB[TARGTAC];
%(***REMOVE THE REG HOLDING THIS COMMON SUB FROM THE REG POOL***)%
STBSYR_CLRBIT(.STBSYR,.RA);
STRGCT_.STRGCT-1;
%(***IF THE COMMON SUB IS DOUBLE-WD, REMOVE THE REG HOLDING THE RIGHT HALF
FROM THE REG POOL***)%
IF .ARGNODE[DBLFLG]
THEN
BEGIN
STBSYR_CLRBIT(.STBSYR,.RA+1);
STRGCT_.STRGCT-1;
END;
IF .ARGNODE[OPRCLS] EQL DATAOPR !IF THE COMMON SUB IS A VAR
AND .CCMNSUB[SAVREGFLG] ! WHICH WILL BE USEFUL IN A REG IN A LATER STMNT
AND .CCMNSUB[A2NGNTFLGS] EQL 0 ! AND WAS NOT PICKED UP WITH "MOVN"
THEN SAVEREG(.CCMNSUB[TARGTAC], !REMEMBER THAT THIS REG
.ARGNODE, ! CONTAINS THE VAL OF THAT VAR
0,.CCMNSUB[SONNXTUSE]);
END
ELSE
%(***IF CANNOT SPARE A REG TO LEAVE THIS COMMON SUBEXPR IN****)%
BEGIN
IF .CCMNSUB[A2VALFLG]
THEN
BEGIN
%(***IF THIS ARG IS THE RIGHT HALF OF AN AONJN WD
AND WE WILL NEED THE WHOLE THING, MUST LOAD AND STORE IT***)%
IF .CCMNSUB[A2IMMEDFLG] AND .CCMNSUB[CSFULLWDFLG]
THEN
BEGIN
RA_AFREEREG(.BSYRG1,.CCMNSUB[SAVREGFLG],FALSE);
CCMNSUB[TARGTAC]_.RA;
REGCLOBB(.CCMNSUB[TARGTAC]); !MUST ASSUME THAT THE PREVIOUS
! CONTENTS OF THE REG USED ARE CLOBBERED
CCMNSUB[TARGADDR]_NXTTMP(FALSE);
END
ELSE
%(***IF THE COMMON SUB IS A REGCONTENTS THAT CAN BE USED, USE IT**)%
IF .ARGNODE[OPRCLS] EQL REGCONTENTS
THEN
BEGIN
CCMNSUB[TARGET]_.ARGNODE[TARGET];
CCMNSUB[A2SAMEFLG]_1;
END
ELSE
BEGIN
CCMNSUB[TARGET]_.ARGNODE;
CCMNSUB[A2SAMEFLG]_1;
END
END
ELSE
BEGIN
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYRG1,.REGCT1);
CCMNSUB[TARGET]_.ARGNODE[TARGET];
CCMNSUB[A2SAMEFLG]_1;
END;
END;
CCMNSUB_.CCMNSUB[CLINK];
END;
END;
GLOBAL ROUTINE ALCIOLST=
%(***************************************************************************
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN IOLIST.
CALLED WITH THE GLOBAL CSTMNT POINTING TO THE STATEMENT FOR
WHICH AN IOLIST IS TO BE PROCESSED.
CALLED WITH THE GLOBALS STBSYR AND STRGCT INDICATING WHICH REGS
ARE AVAILABLE FOR USE.
***************************************************************************)%
BEGIN
EXTERNAL ALCINREG,ALCINTMP,ALCTARY;
LOCAL BASE IOLELEM;
LOCAL SAVSTMNT,SAVBSYR,SAVRGCT;
%(***GET PTR TO 1ST ELEM ON IOLIST TO BE PROCESSED***)%
IOLELEM_.CSTMNT[IOLIST];
%(****SAVE PTR TO CURRENT STATEMENT (IF THERE ARE DO-STMNTS ON THE IOLIST
WILL CLOBBER CSTMNT,STBSYR,STRGCT)*****)%
SAVSTMNT_.CSTMNT;
SAVBSYR_.STBSYR;
SAVRGCT_.STRGCT;
%(*****WALK THRU THE ELEMENTS ON THE IOLIST******)%
UNTIL .IOLELEM EQL 0
DO
BEGIN
IF .IOLELEM[OPRCLS] EQL STATEMENT
THEN
BEGIN
CSTMNT_.IOLELEM;
ALCSTMN();
%(**IF THIS STMNT IS A DO STMNT, MUST TERMINATE THE PREVIOUS BASIC BLOCK
(SINCE SOME VAR MIGHT BE CLOBBERED LATER IN THE LIST AND ON
LOOPING BACK MIGHT MAKE A FALSE ASSUMPTION ABOUT ITS VAL
BEING IN A REG)
***)%
IF .IOLELEM[SRCID] EQL DOID
THEN
BEGIN
CLRRGSTATE(); !MUST DELETE ALL ASSUMPTIONS ABOUT
! THE CONTENTS OF REGISTERS
IF .IOLELEM[SAVREGFLG] !IF THE DO INDEX WILL BE USEFUL
! LATER, REMEMBER WHAT REG ITS IN
THEN SAVEREG(.IOLELEM[DOIREG],
.IOLELEM[DOSYM],0,.IOLELEM[SRCSONNXTUSE],
FALSE);
END;
END
ELSE
IF .IOLELEM[OPRCLS] EQL IOLSCLS
THEN
BEGIN
CASE .IOLELEM[OPERSP] OF SET
%(***FOR A DATACALL NODE - PERFORM REG ALLOC FOR THE
EXPRESSION UNDER THIS NODE*****)%
BEGIN
TREEPTR_.IOLELEM[DCALLELEM];
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
BEGIN
LOCAL STBSY1,STRG1;
IF .TREEPTR[DBLFLG] THEN
BEGIN
STBSY1_DPBSYREGS(.STBSYR);
STRG1_ONESCOUNT(.STBSY1);
END ELSE
BEGIN
STBSY1_.STBSYR;
STRG1_.STRGCT;
END;
ALCINREG(AFREEREG(.STBSY1,FALSE,.TREEPTR[DBLFLG]),.STBSY1,.STRG1);
END;
IF .INPFLAG !IF INPUT IS BEING PERFORMED
THEN VARCLOBB(.IOLELEM[DCALLELEM]) !THE VAL OF THE VAR WILL BE
! CLOBBERED, HENCE MUST FORGET ASSUMPTIONS
! ABOUT THAT VAR BEING IN SOME REG
END;
%(***FOR AN SLISTCALL NODE - PERFORM REG ALLOC FOR THE OPERATION
TO CALCULATE THE NUMBER OF ELEMS IN THE ARRAY (IF ARRAY
HAS VARIABLE BOUNDS)****)%
BEGIN
TREEPTR_.IOLELEM[SCALLCT];
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
ALCINREG(AFREEREG(.STBSYR,FALSE,.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
IF .INPFLAG !IF INPUT IS BEING PERFORMED
THEN VARCLOBB(.IOLELEM[SCALLELEM]); !MUST ASSUME THAT ELEMENTS OF THE
! ARRAY AND ALL VARS EQUIVALENCED TO THEM
! ARE CLOBBERED
END;
%(***FOR AN IOLSTCALL NODE***************)%
ALCIOCALL(.IOLELEM);
%(****FOR AN E1LISTCALL NODE - OPTIMIZED CODE ONLY***)%
BEGIN
LOCAL BASE SAVCSTMNT;
SAVCSTMNT_.CSTMNT;
CSTMNT_.IOLELEM;
ALCCMNSB();
CSTMNT_.SAVCSTMNT;
ALCE1LIST(.IOLELEM,.STBSYR,.STRGCT)
END;
%(***FOR AN E2LISTCALL NODE - OPTIMIZED CODE ONLY***)%
BEGIN
LOCAL BASE SAVCSTMNT;
SAVCSTMNT_.CSTMNT;
CSTMNT_.IOLELEM;
ALCCMNSB();
CSTMNT_.SAVCSTMNT;
ALCE2LIST(.IOLELEM,.STBSYR,.STRGCT)
END
TES;
END;
%(***RESTORE STBSYR,STRGCT FOR THE NEXT ELEM ON IOLIST***)%
STBSYR_.SAVBSYR;
STRGCT_.SAVRGCT;
%(***GO ON TO NEXT ELEMENT****)%
IOLELEM_.IOLELEM[CLINK];
END;
CSTMNT_.SAVSTMNT;
END;
GLOBAL ROUTINE ALCIOCALL(IOLSNODE)=
%(***************************************************************************
TO PERFORM REGISTER ALLOCATION FOR AN IOLSTCALL NODE.
THE ARG IOLSNODE PTS TO AN IOLSTCALL NODE.
FOR IOLIST ELEMENTS THAT REQUIRE COMPUTATION, LEAVE AS MANY
AS POSSIBLE IN THE REGS IN WHICH THEY WERE COMPUTED (RATHER THAN
STORING THEM IN TEMPORARIES). ALSO LEAVE AS MANY ARRAY OFFSETS
AS POSSIBLE IN REGISTERS.
***************************************************************************)%
BEGIN
EXTERNAL RGTOSAVE;
EXTERNAL ALCTARY;
MAP BASE IOLSNODE;
EXTERNAL TREEPTR;
MAP PEXPRNODE TREEPTR;
OWN BASE IOLELEM;
OWN REGSREQ;
OWN FREGCT,BSYREGS; !REGISTERS AVAILABLE FOR USE AT THE CURRENT PT IN
! THE IOLIST (AS EARLY ELEMS GET LEFT IN REGS,
! THESE VARIABLES ARE ADJUSTED SO THAT LATER ELEMS
! WONT CLOBBER THOSE REGS)
OWN FRGCT1,BSYRG1; !FOR A DATACALL NODE - THESE ARE ADJUSTED TO ACCOUNT
! FOR A DOUBLE PRECISION EXPRESSION
OWN RA;
OWN PEXPRNODE ARGNODE;
OWN SAVSTMNT;
%(***SAVE VAL OF THE GLOBAL CSTMNT***)%
SAVSTMNT_.CSTMNT;
%(***PERFORM REGISTER ALLOCATION FOR ANY COMMON SUBEXPRS ON THIS IOLST***)%
CSTMNT_.IOLSNODE;
ALCCMNSB();
%(***GET NUMBER OF REGS REQUIRED FOR REST OF THIS IOLSTCALL***)%
REGSREQ_.IOLSNODE[SRCCMPLX];
BSYREGS_.STBSYR;
FREGCT_.STRGCT;
%(***WALK THRU ELEMENTS ON THIS IOLSTCALL***)%
IOLELEM_.IOLSNODE[IOLSTPTR];
UNTIL .IOLELEM EQL 0
DO
BEGIN
CASE .IOLELEM[OPERSP] OF SET
%(***FOR A DATACALL NODE****)%
BEGIN
TREEPTR_.IOLELEM[DCALLELEM];
ARGNODE_.TREEPTR;
IF .INPFLAG ! IF INPUT IS BEING PERFORMED
THEN !MUST ASSUME THE VAL OF THE VAR IS CLOBBERED
VARCLOBB(.ARGNODE); ! AND HENCE THAT ASSUMPTIONS ABOUT REGS CONTAINING
! THE VAR ARE NOW FALSE
IF .ARGNODE[OPRCLS] NEQ DATAOPR ! IF NEED TO CALCULATE
! DO NOT NEED TO GET A NEW REGISTER IF THIS ELEMENT IS A REGCONTENTS NODE
THEN IF .ARGNODE[OPRCLS] NEQ REGCONTENTS
![764] NO REGISTER IS NEEDED FOR AN IMMEDIATE ARRAY REFERENCE
%[764]% THEN IF NOT (.ARGNODE[OPRCLS] EQL ARRAYREF AND
%[764]% .ARGNODE[ARG2PTR] EQL 0)
THEN ! THE VALUE OF THIS ITEM
BEGIN ! THEN ALLOCATE THE REGS
%(***IF THIS ELEMENT IS DOUBLE-PREC - MUST ADJUST SET OF FREE REGS***)%
IF .ARGNODE[DBLFLG]
THEN
(BSYRG1_DPBSYREGS(.BSYREGS); FRGCT1_ONESCOUNT(.BSYRG1) )
ELSE
(BSYRG1_.BSYREGS; FRGCT1_.FREGCT);
%(***IF THERE ARE ENOUGH REGS TO LEAVE ALL FURTHER ARGS IN REGS***)%
![1142] Since the complexity count is only 6 bits worth, the field may
![1142] overflow for a complicated IOLISTCALL node, and the number of
![1142] registers required may appear as 0, or the correct number modulo 64.
![1142] Check for these cases, and leave two free registers so that the temp
![1142] allocator can still succeed with array refs.
%[1142]% IF .REGSREQ LSS .FREGCT-1 AND .REGSREQ GTR 0
THEN
BEGIN
ALCINREG(AFREEREG(.BSYRG1,FALSE,.TREEPTR[DBLFLG]),.BSYRG1,.FRGCT1);
%(***IF THIS ARG WAS LEFT IN A REG, MUST TAKE THAT REG
OUT OF THE SET OF REGS AVAILABLE FOR USE FOR
LATER ELEMENTS****)%
RA_RGTOSAVE(.ARGNODE);
IF .RA NEQ -1
THEN
BEGIN
BSYREGS_CLRBIT(.BSYREGS,.RA);
%(***IF THIS ARG WAS DOUBLE-PREC MUST ALSO
REMOVE THE REG AFTER RA FROM THE SET***)%
IF .ARGNODE[DBLFLG]
THEN
BEGIN
BSYREGS_CLRBIT(.BSYREGS,.RA+1);
FREGCT_.FREGCT-2;
REGSREQ_.REGSREQ-2;
END
ELSE
BEGIN
FREGCT_.FREGCT-1;
REGSREQ_.REGSREQ-1;
END;
END;
END
%(***IF THERE ARE NOT ENOUGH REGS, THEN IF THIS ELEM IS COMPUTED,
LEAVE IT IN A TEMP***)%
ELSE
BEGIN
IF .TREEPTR[OPRCLS] EQL ARRAYREF
THEN
%(***FOR AN ARRAYREF - IF THE SS IS ALREADY IN A REG, CAN PASS
FOROTS ARG IN THE FORM "ADDR(R)"
OTHERWISE, MUST MATERIALIZE THE ADDRESS REFERENCED***)%
BEGIN
IF .TREEPTR[A2VALFLG] AND NOT .TREEPTR[A2NEGFLG]
THEN
BEGIN
OWN PEXPRNODE SSNODE;
SSNODE_.TREEPTR[ARG2PTR];
IF (.SSNODE[OPRCLS] EQL REGCONTENTS) OR
(.SSNODE[OPRCLS] EQL CMNSUB
AND .SSNODE[INREGFLG])
THEN
BEGIN
%(***SET THE "INDEX" FIELD TO
BE USED TO REFERENCE THE ELEMENT
TO THE REG THAT HOLDS THE SS***)%
TREEPTR[TARGXF]_.SSNODE[TARGTAC];
TREEPTR[A2SAMEFLG]_1
END
ELSE IOLELEM[DCALLELEM]_ALCTARY(.BSYRG1,.FRGCT1)
END
ELSE
IOLELEM[DCALLELEM]_ALCTARY(.BSYRG1,.FRGCT1)
END
ELSE
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYRG1,.FRGCT1);
%(***IF AN ARG THAT MIGHT HAVE BEEN LEFT IN A REG WAS
LEFT IN A TEMP, CAN REDUCE THE NUMBER OF FUTURE REGS
REQUIRED BY 1***)%
IF .TREEPTR[OPRCLS] NEQ DATAOPR AND .TREEPTR[OPRCLS] NEQ CMNSUB
THEN
BEGIN
IF .TREEPTR[COMPLEXITY] NEQ 0
THEN
BEGIN
%(***FOR DOUBLE-WD VAL HAVE 2 EXTRA REGS**)%
IF .TREEPTR[DBLFLG]
THEN REGSREQ_.REGSREQ-2
ELSE REGSREQ_.REGSREQ-1;
END
END;
END;
END; ! OF IF NEQ DATAOPR
END;
%(***FOR AN SLISTCALL NODE***)%
BEGIN
IF .INPFLAG !IF INPUT IS BEING PERFORMED
THEN VARCLOBB(.IOLELEM[SCALLELEM]); !MUST ASSUME THAT ELEMS OF THIS ARRAY
! (AND VARS POTENTIALLY EQUIVALENCED TO THEM)
! ARE CLOBBERED
TREEPTR_.IOLELEM[SCALLCT];
IF .TREEPTR[OPRCLS] NEQ DATAOPR
THEN
%(***DONT BOTHER TO TRY TO LEAVE THIS IN A REG***)%
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYREGS,.FREGCT);
END;
%(***AN IOLSTCALL WITHIN AN IOLSTCALL IS ILLEGAL***)%
BEGIN
END;
%(***FOR AN E1LISTCALL NODE - OPTIMIZED CODE ONLY***)%
ALCE1LIST(.IOLELEM,.BSYREGS,.FREGCT);
%(***FOR AN E2LISTCALL NODE - OPTIMIZED CODE ONLY***)%
ALCE2LIST(.IOLELEM,.BSYREGS,.FREGCT)
TES;
%(***GO ON TO NEXT ELEMENT***)%
IOLELEM_.IOLELEM[CLINK];
END;
%(***RETSORE CSTMNT***)%
CSTMNT_.SAVSTMNT;
END;
GLOBAL ROUTINE ALCE1LIST(IOLELEM,BSYREGS,FREGCT)=
%(**********************************************************************
PERFORM REGISTER ALLOCATION FOR AN E1LISTCALL NODE
STORE THE RESULTS OF ALL CALCULATIONS REQUIRED BY
ELEMENTS IN THE E1LISTCALL NODE IN TEMPORARIES
**********************************************************************)%
BEGIN
MAP BASE IOLELEM;
LOCAL BASE IOARRAY;
EXTERNAL ALCTVARR; !ALLOCATE THE VAL OF AN ARRAY ELEM TO
! A TEMP
EXTERNAL ALCTARY,ALCINTMP;
EXTERNAL TREEPTR;
MAP PEXPRNODE TREEPTR;
%(***ALLOCATE THE COUNT EXPRESSION***)%
TREEPTR_.IOLELEM[ECNTPTR];
IF .TREEPTR[OPRCLS] EQL ARRAYREF !REF TO AN ARRAY ELEM
THEN IOLELEM[ECNTPTR]_ALCTVARR(.BSYREGS,.FREGCT) !LINK A STORECLS NODE INTO THE TREE
ELSE
IF .TREEPTR[OPRCLS] NEQ DATAOPR THEN
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYREGS,.FREGCT);
%(***ALLOCATE THE INCREMENT EXPRESSION***)%
TREEPTR_.IOLELEM[E1INCR];
IF .TREEPTR[OPRCLS] EQL ARRAYREF
THEN IOLELEM[E1INCR]_ALCTVARR(.BSYREGS,.FREGCT)
ELSE
IF .TREEPTR[OPRCLS] NEQ DATAOPR THEN
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYREGS,.FREGCT);
%(***ALLOCATE THE ARRAY REFERENCES***)%
IOARRAY_.IOLELEM[ELSTPTR];
WHILE .IOARRAY NEQ 0 DO
BEGIN
LOCAL BASE VARNAME;
TREEPTR_.IOARRAY[E2ARREFPTR];
IF .TREEPTR[OPRCLS] EQL ARRAYREF THEN
IF .TREEPTR[ARG2PTR] NEQ 0 THEN
![744]WE MUST ADJUST THE REGISTER MASK BEFORE ALLOCATING FOR THE
![744] ARRAY REFERENCE, ESPECIALLY IF THE ARRAY IS DOUBLE WORD!
![744] OTHERWISE, IF AN ODD REGISTER IS IN USE WHILE ITS EVEN
![744] COUNTERPART IS NOT, THEN THE ODD REGISTER MAY GET OVER-USED.
%[744]% BEGIN
%[744]% LOCAL FRGCT1,BSYRG1;
%[744]% IF .TREEPTR[DBLFLG] THEN
%[744]% (BSYRG1_DPBSYREGS(.BSYREGS); FRGCT1_ONESCOUNT(.BSYRG1))
%[744]% ELSE
%[744]% (BSYRG1_.BSYREGS; FRGCT1_.FREGCT);
%[744]% IOARRAY[E2ARREFPTR]_ALCTARY(.BSYRG1,.FRGCT1)
%[744]% END;
VARNAME_.IOARRAY[E2ARREFPTR];
IF .INPFLAG THEN VARCLOBB(
IF .VARNAME[OPRCLS] NEQ ARRAYREF THEN .VARNAME ELSE
.VARNAME[ARG1PTR]);
IOARRAY_.IOARRAY[CLINK]
END
END;
GLOBAL ROUTINE ALCE2LIST(IOLELEM,BSYREGS,FREGCT)=
%(**********************************************************************
PERFORM REGISTER ALLOCATION FOR AN E2LISTCALL NODE
STORE THE RESULTS OF ALL CALCULATIONS REQUIRED BY
ELEMENTS IN THE E2LISTCALL NODE IN TEMPORARIES
**********************************************************************)%
BEGIN
EXTERNAL ALCTARY,ALCINTMP;
LOCAL BASE IOARRAY;
MAP BASE IOLELEM;
EXTERNAL TREEPTR;
MAP PEXPRNODE TREEPTR;
%(***ALLOCATE THE COUNT EXPRESSION***)%
TREEPTR_.IOLELEM[ECNTPTR]; !ALLOCATE EXPRESSION
IF .TREEPTR[OPRCLS] EQL ARRAYREF !REF TO AN ARRAY ELEM
THEN IOLELEM[ECNTPTR]_ALCTVARR(.BSYREGS,.FREGCT) !LINK A STORECLS NODE INTO THE TREE
ELSE
IF .TREEPTR[OPRCLS] NEQ DATAOPR THEN !IN A TEMPORARY
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYREGS,.FREGCT);
%(***ALLOCATE THE INCREMENT EXPRESSIONS***)%
IOARRAY_.IOLELEM[ELSTPTR]; !LOCATE LIST
WHILE .IOARRAY NEQ 0 DO
BEGIN
TREEPTR_.IOARRAY[E2INCR]; !ALLOCATE EXPRESSION
IF .TREEPTR[OPRCLS] EQL ARRAYREF
THEN IOARRAY[E2INCR]_ALCTVARR(.BSYREGS,.FREGCT)
ELSE
IF .TREEPTR[OPRCLS] NEQ DATAOPR THEN
ALCINTMP(NXTTMP(.TREEPTR[DBLFLG]),.BSYREGS,.FREGCT);
IOARRAY_.IOARRAY[CLINK]
END;
%(***ALLOCATE THE ARRAYREF COMPUTATIONS***)%
IOARRAY_.IOLELEM[ELSTPTR]; !LOCATE LIST
WHILE .IOARRAY NEQ 0 DO
BEGIN
LOCAL BASE VARNAME;
TREEPTR_.IOARRAY[E2ARREFPTR]; !ALLOCATE EXPRESSION
IF .TREEPTR[OPRCLS] EQL ARRAYREF THEN
IF .TREEPTR[ARG2PTR] NEQ 0 THEN
![744] WE MUST ADJUST THE REGISTER MASK BEFORE ALLOCATING FOR THE
![744] ARRAY REFERENCE, ESPECIALLY IF THE ARRAY IS DOUBLE WORD!
![744] OTHERWISE, IF AN ODD REGISTER IS IN USE WHILE ITS EVEN
![744] COUNTERPART IS NOT, THEN THE ODD REGISTER MAY GET OVER-USED.
%[744]% BEGIN
%[744]% LOCAL FRGCT1,BSYRG1;
%[744]% IF .TREEPTR[DBLFLG] THEN
%[744]% (BSYRG1_DPBSYREGS(.BSYREGS); FRGCT1_ONESCOUNT(.BSYRG1))
%[744]% ELSE
%[744]% (BSYRG1_.BSYREGS; FRGCT1_.FREGCT);
%[744]% IOARRAY[E2ARREFPTR]_ALCTARY(.BSYRG1,.FRGCT1)
%[744]% END;
VARNAME_.IOARRAY[E2ARREFPTR];
IF .INPFLAG THEN VARCLOBB(
IF .VARNAME[OPRCLS] NEQ ARRAYREF THEN .VARNAME ELSE
.VARNAME[ARG1PTR]);
IOARRAY_.IOARRAY[CLINK]
END
END;
GLOBAL ROUTINE LHINREGALC=
%(*****
ROUTINE TO PERFORM REGISTER ALLOCATION FOR AN ASSIGNMENT STATEMENT
WHEN THE LEFT-HAND-SIDE IS ALLOCATED TO A REGISTER.
THIS ROUTINE ATTEMPTS TO COMPUTE THE VALUE OF THE RIGHT-HAND-SIDE
INTO THAT REGISTER. IT IS ABLE TO DO SO IF EITHER:
1. THERE IS NO REFERENCE TO THE LHS VARIABLE IN THE
RHS EXPRESSION
2. THERE IS A REFERENCE TO THE LHS VARIABLE AT A DEPTH OF
1 OR 2 WITHIN THE RHS EXPRESSION.
RETURNS TRUE IF SUCCEEDED, FALSE IF FAILED (IN WHICH CASE REGISTER
ALLOCATION FOR THIS EXPRESSION MUST STILL BE PERFORMED)
*****)%
BEGIN
EXTERNAL CLOBBNX; !NEED THIS FOR TEST
REGISTER PEXPRNODE RHNODE;
OWN PEXPRNODE LHNODE;
OWN RA;
OWN PEXPRNODE ARG1NODE;
REGISTER PEXPRNODE ARG2NODE;
%(***LOCAL ROUTINE TO SET REG FOR COMPUTATION OF RIGHT HAND EXPR EQUAL TO
REG TO WHICH LHS VARIABLE WAS ALLOCATED*****)%
ROUTINE SETRHRGTOLH=
BEGIN
RHNODE[TARGTAC]_.LHNODE[TARGTAC];
%[625]% RHNODE[INREGFLG]_1;
CSTMNT[ASMNTREG]_.LHNODE[TARGTAC];
![721] SINCE WE ARE USING THE REGISTER, INVALIDATE ANY PREVIOUS USE
%[721]% REGCLOBB(.CSTMNT[ASMNTREG]);
CSTMNT[A1SAMEFLG]_1;
CSTMNT[A2SAMEFLG]_1;
END;
%(***LOCAL ROUTINE TO SPECIFY THAT THE COMPUTATION OF THE VALUE OF THE NODE
"PNODE" BE PERFORMED IN THE REGISTER USED FOR LHS WHEN ARG1
UNDER "PNODE" IS EQUAL TO LHS
CAN BE CALLED FOR PNODE OF OPRCLS:
ARITHMETIC,BOOLEAN,SPECOP
****)%
ROUTINE CMPNODINLH(PNODE)=
BEGIN
MAP PEXPRNODE PNODE;
PNODE[A1SAMEFLG]_1;
PNODE[TARGTAC]_.LHNODE[TARGTAC];
%[625]% PNODE[INREGFLG]_1;
%(****PERFORM REG ALLOC FOR ARG2 UNDER PNODE***)%
IF NOT .PNODE[A2VALFLG] AND .PNODE[OPRCLS] NEQ SPECOP
THEN
BEGIN
TREEPTR_.PNODE[ARG2PTR];
ALCINREG(AFREEREG(.STBSYR,FALSE,.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
END;
END;
ROUTINE CMPRHINLH=
%(***LOCAL ROUTINE TO ALLOCATE THE COMPUTATION OF RHNODE TO BE
PERFORMED IN THE REGISTER ALLOCATED TO LHS, WHEN THE FIRST
ARG UNDER THE FIRST ARG OF RHNODE IS KNOWN TO BE EQUAL TO
THE VARIABLE ON THE LHS
****)%
BEGIN
%(***IF THE COMPUTATION OF ARG2 UNDER RHS INCLUDES A REFERENCE
TO THE VARIABLE FROM THE LHS, MUST COMPUTE ARG2 BEFORE
COMPUTE ARG1 (SINCE THE COMPUTATION OF ARG1 WILL
CLOBBER THE REG THAT HOLDS THAT VAR)
***)%
IF .ARG2NODE[RESRFFLG] AND NOT .RHNODE[RVRSFLG]
THEN
BEGIN
RHNODE[RVRSFLG]_1;
%(**IF ON COMPLEXITY PASS WE ALLOCATED ARG2 TO BE COMPUTED
INTO FN-RETURN REG, AND THE COMPUTATION OF ARG1 WILL
CLOBBER FN-RETURN REG, THEN WE MUST UNDO THAT ALLOCATION***)%
IF .ARG2NODE[ALCRETREGFLG] AND .ARG1NODE[FNCALLSFLG]
THEN
BEGIN
ARG2NODE[ALCRETREGFLG]_0;
ARG2NODE[INREGFLG]_0;
ARG2NODE[A1SAMEFLG]_0;
ARG2NODE[A2SAMEFLG]_0;
END
END;
%(***PERFORM REGISTER ALLOCATION FOR THE COMPUTATION OF ARG2 UNDER RHNODE
(WE KNOW THAT THE VAL OF ARG1 WILL BE LEFT IN THE REG IN WHICH LHS
IS ALLOCATED)
****)%
IF NOT .RHNODE[A2VALFLG] AND .RHNODE[OPRCLS] NEQ SPECOP
THEN
BEGIN
TREEPTR_.ARG2NODE;
ALCINREG(AFREEREG(.STBSYR,FALSE,.TREEPTR[DBLFLG]),.STBSYR,.STRGCT);
%(***IF ARG2 IS COMPUTED BEFORE ARG1, THEN MUST NOT USE
THE REG IN WHICH VAL OF ARG2 WAS LEFT IN COMPUTING ARG1**)%
IF .RHNODE[RVRSFLG]
THEN
BEGIN
OWN RB;
IF (RB_RGTOSAVE(.ARG2NODE)) NEQ -1 !IF SOME REG MUST BE PRESERVED
! TO PRESERVE VAL OF ARG2
THEN
BEGIN
STBSYR_CLRBIT(.STBSYR,.RB); !TAKE THAT REG OUT OF SET AVAILABL
%(***IF THAT REG IS THE REG TO WHICH LHS WAS
ALLOCATED, ARE IN AN IMPOSSIBLE SITUATION.
THIS SHOULD NEVER OCCUR***)%
IF .RB EQL .LHNODE[TARGTAC] THEN CGERR();
END;
END;
END;
%(***PERFORM ALLOCATION OF ARG1 UNDER RHNODE, COMPUTING ITS VAL INTO
THE REG USED FOR LHS***)%
CMPNODINLH(.ARG1NODE);
RHNODE[TARGTAC]_.ARG1NODE[TARGTAC];
RHNODE[A1SAMEFLG]_1;
SETRHRGTOLH(); !SET FIELDS OF CSTMNT TO INDICATE THAT RHNODE WAS
! COMPUTED INTO THE REG FOR LHNODE
END;
ROUTINE ALCTORETREG=
%(*********************
ROUTINE TO ALLOCATE THE RIGHT HAND SIDE WHEN IT HAS BEEN DETERMINED
THAT IT CAN BE COMPUTED INTO THE FN RETURN REG, AND THE LHS
IS ALSO A REGCONTENTS FOR THE FN RETURN REG
***********************)%
BEGIN
TREEPTR_.RHNODE;
ALCINREG(AFREEREG(.STBSYR,FALSE,.RHNODE[DBLFLG]),.STBSYR,.STRGCT);
CSTMNT[ASMNTREG]_RETREG; !USE RETREG FOR THE ASSIGNMNET
CSTMNT[A1SAMEFLG]_1;
CSTMNT[A2SAMEFLG]_1;
RETURN TRUE
END;
ROUTINE MUSTSAVLHREG(ANODE)=
%(***************
TESTS WHETHER THE VALUE OF ANODE WILL BE INACCESSIBLE IF THE
REGISTER THAT HOLDS THE VARIABLE ON THE LHS HAS BEEN CLOBBERED.
THIS IS TRUE ONLY IF ANODE IS AN ARRAYREF THAT WILL HAVE THE
LHS VAR AS ITS SUBSCRIPT OR FOR DUMMY TYPE CONVERSION NODES
THAT HAVE THE LHS VAR UNDER THEM
******************)%
BEGIN
MAP PEXPRNODE ANODE;
IF .ANODE EQL .LHNODE THEN RETURN TRUE !TO REF THE LHS VAR ITSELF,
! THE VAL MUST BE PRESERVED
ELSE
IF .ANODE[OPRCLS] EQL ARRAYREF !FOR AN ARRAYREF, IF THE INDEX
THEN RETURN MUSTSAVLHREG(.ANODE[ARG2PTR]) ! IS A NODE THAT REQUIRES THE LHS TO
! BE PRESERVED
ELSE
IF .ANODE[OPRCLS] EQL TYPECNV
THEN
BEGIN
%(***IF THE ARG UNDER A DUMMY TYPE-CNV NODE REQUIRES THE REG TO
BE PRESERVED, THEN THE TYPE-CNVNODE DOES ALSO***)%
IF NOCNV(ANODE) THEN RETURN MUSTSAVLHREG(.ANODE[ARG2PTR])
ELSE RETURN FALSE
END
ELSE RETURN FALSE
END;
%[1067]% ROUTINE NOCMSBINR1=
![1067] %(***********************
![1067] ROUTINE TO TEST IF A COMMON SUBEXPRESSION HAS BEEN ALLOCATED
![1067] IN REGISTER 1. RETURN TRUE IF NONE IN REG 1
![1067] ************************)%
%[1067]% BEGIN
%[1067]% REGISTER T1;
%[1067]% MAP PEXPRNODE T1;
%[1067]% T1_.CSTMNT[SRCCOMNSUB];
%[1067]% IF .T1 NEQ 0 THEN
%[1067]% DO IF .T1[TARGADDR] EQL RETREG+1 THEN RETURN FALSE
%[1067]% ELSE T1_.T1[CLINK]
%[1067]% WHILE .T1 NEQ 0;
%[1067]% RETURN TRUE
%[1067]% END;
LHNODE_.CSTMNT[LHEXP];
%(***IF RHS IS A SCALAR, SIMPLY SET TARGET TO REG ALLOCATED FOR LHS***)%
IF .CSTMNT[A2VALFLG]
THEN
BEGIN
CSTMNT[ASMNTREG]_.LHNODE[TARGTAC];
CSTMNT[A1SAMEFLG]_1;
IF .CSTMNT[RHEXP] EQL .LHNODE
OR REGCONTAINING(.CSTMNT[RHEXP]) EQL .LHNODE[TARGTAC] !IF THE VAR ON RHS WAS ALREADY IN THE DESIRED REG
THEN
CSTMNT[A2SAMEFLG]_1
ELSE REGCLOBB(.CSTMNT[ASMNTREG]); !IF LEFT SOME VAR IN LHS REG WHILE
! COMPUTING RHS, THAT VAR IS NOW NO LONGER THERE
RETURN TRUE;
END;
RA_.LHNODE[TARGTAC];
RHNODE_.CSTMNT[RHEXP];
%(***IF THE LHS IS THE FN-RETURN REG AND THE RHS HAS ALREADY BEEN DETERMINED
TO BE EVALUATED TO IT, THEN JUST DO
REST OF ALLOCATION FOR RHS EXPRESSION***)%
IF .RA EQL RETREG AND .RHNODE[ALCRETREGFLG] AND .RHNODE[TARGTAC] EQL RETREG AND .RHNODE[INREGFLG]
THEN RETURN ALCTORETREG();
%(***IF RHS IS AN ARRAY-REF - LOAD THE VAL INTO THE DESIRED REG***)%
IF .RHNODE[OPRCLS] EQL ARRAYREF
THEN
BEGIN
TREEPTR_.RHNODE;
ALCARRAY(.STBSYR,.STRGCT);
CSTMNT[ASMNTREG]_.LHNODE[TARGTAC];
CSTMNT[A1SAMEFLG]_1;
REGCLOBB(.CSTMNT[ASMNTREG]);
RETURN TRUE;
END;
%(***IF THERE IS NO REFERENCE TO THE VARIABLE ON THE LHS IN THE
EXPRESSION ON THE RHS, SIMPLY ALLOCATE THE EXPRESSION TO BE
COMPUTED INTO THE REG USED FOR THE VARIABLE IF POSSIBLE
****)%
IF NOT .RHNODE[RESRFFLG]
AND NOT (.RA EQL RETREG AND .RHNODE[FNCALLSFLG]) !IF LHS IS FN RETURN REG
! AND HAVE FNCALLS ON RHS
THEN
BEGIN
OWN STBSYR1; !SET OF REGS AVAILABLE FOR USE IN COMPUTING THE
! THE VAL OF THE RHS
%(***FOR COMPUTING THE RHS OF THIS STMNT, CAN USE THE REG TO WHICH
THE LHS WAS ALLOCATED (SINCE THE LHS VARIABLE DOES NOT OCCUR
IN THE RHS EXPRESSION)***)%
STBSYR1_SETBIT(.STBSYR,.RA);
![1067] %(**WHEN TARGETTING TO REG 0 (FN RET REG) ALLOW REG 1 TO BE
![1067] USED IF THERE ARE NO COMMON SUBEXPRS ON STMNT WHICH USE IT**)%
%[1067]% IF .RA EQL RETREG AND NOCMSBINR1()
THEN STBSYR1_SETBIT(.STBSYR1,RETREG+1);
TREEPTR_.RHNODE;
ALCINREG(.RA,.STBSYR1,ONESCOUNT(.STBSYR1));
CSTMNT[ASMNTREG]_.LHNODE[TARGTAC];
CSTMNT[A1SAMEFLG]_1;
IF .RHNODE[TARGTAC] EQL .CSTMNT[ASMNTREG] AND .RHNODE [INREGFLG]
THEN
CSTMNT[A2SAMEFLG]_1
ELSE REGCLOBB(.CSTMNT[ASMNTREG]); !IF LEFT SOME VAR IN LHS REG WHILE
! COMPUTING RHS, THAT VAR IS NOW NO LONGER THERE
RETURN TRUE;
END;
%(***IF RHS CONTAINS A REFERENCE TO LHS VAR AND IS A SPECIAL OPERATOR
(P2MUL OR P2DIV), CHECK FOR ARG1 OF THAT OPERATOR EQUAL
TO THE LHS - IF IT IS, PERFORM THE OPERATION IN THE REG
ALLOCATED TO LHS - OTHERWISE GIVE UP
****)%
IF .RHNODE[OPRCLS] EQL SPECOP
THEN
BEGIN
! MUST NOT CLOBBER LHS REG IF P2PL1OP OR EXPCIOP NOT A POWER OF 2
IF .RHNODE [OPERSP] EQL P2PL1OP OR
(.RHNODE [OPERSP] EQL EXPCIOP AND
NOT POWOF2 (.RHNODE [ARG2PTR]))
THEN RETURN FALSE;
IF .RHNODE[ARG1PTR] EQL .LHNODE
THEN
BEGIN
SETRHRGTOLH();
RHNODE[A1SAMEFLG]_1;
RETURN TRUE;
END
ELSE
RETURN FALSE;
END;
%(***IF RHS CONTAINS A REFERENCE TO LHS VAR AND IS A RELATIONAL,
FUNCTION CALL, TYPE-CONVERSION, OR NEG/NOT - DON'T BOTHER
****)%
IF .RHNODE[OPRCLS] NEQ ARITHMETIC AND .RHNODE[OPRCLS] NEQ BOOLEAN
THEN
RETURN FALSE;
%(********WHEN THE LHS IS THE FN RETURN REG AND THE RHS IS AN ARITH OR BOOLEAN
EXPRESSION THAT CONTAINS FUNCTION CALLS BUT WAS NOT ALLOCATED TO THE FN RETURN
REG ALREADY, CHECK FOR RHS OF THE FORM:
<EXPR> OP <FN-CALL>
OR <EXPR> OP <EXPR ALLOCATED TO FN RETURN REG>
AND REVERSE THE 2 OPERATORS IF CAN DO SO
*********)%
IF .RA EQL RETREG
THEN
BEGIN
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
IF .ARG2NODE[ALCRETREGFLG] !IF ARG2 WAS ALLOCATED TO FN RETURN REG
AND .ARG2NODE[INREGFLG] AND .ARG2NODE[TARGTAC] EQL RETREG
AND COMMUTATIVE(RHNODE) !AND THE RHS EXPRESSION IS COMMUTATIVE
AND NOT .ARG1NODE[FNCALLSFLG] !AND ARG1 DOES NOT INCLUDE FN CALLS
THEN
BEGIN
EXCHARGS(.RHNODE); !LET ARG1 BE THE ARG COMPUTED INTO FN RETURN REG
RHNODE[RVRSFLG]_0; !ALWAYS COMPUTE THAT ARG FIRST
RHNODE[ALCRETREGFLG]_1; !COMPUTE THE RHS IN THE FN RET REG
RHNODE[TARGTAC]_RETREG;
RHNODE[INREGFLG]_1;
RHNODE[A1SAMEFLG]_1; !ARG1 OF RHS WONT HAVE TO BE LOADED INTO THE REG
RETURN ALCTORETREG()
END
ELSE RETURN FALSE; !IF LHS IS FN RETURN REG, RHS CONTAINS FN CALLS
! AND NEITHER RHS, NOR ARG2 UNDER RHS WAS ALLOCATED TO FN
! RET REG, GIVE UP ON OPTIMALITY
END;
%(*******WHEN RHS EXPRESSION IS ARITHMETIC OR BOOLEAN AND CONTAINS
A REFERENCE TO LHS VAR***)%
! CONSIDER CASES LIKE:
! I=I/J
! I=(I+K)/J
! I=J+(I/K)
! AND OTHER ASSOCIATED PROBLEMS!
! THESE ALL DEPEND UPON THE REG AFTER THE ONE
! IN WHICH THE LHS IS LIVING GETTING OVERWRITTEN BY
! SOME OPERATION PERFORMED DIRECTLY IN THE REG FOR LHS.
IF CLOBBNX(.RHNODE) THEN RETURN FALSE;
%(***IF ARG1 IS EQUAL TO LHS VAR, SIMPLY PERFORM OP IN LHS REG***)%
IF .RHNODE[ARG1PTR] EQL .LHNODE
THEN
BEGIN
SETRHRGTOLH();
CMPNODINLH(.RHNODE);
RETURN TRUE;
END;
%(***IF ARG2 IS EQUAL TO LHS VAR. ATTEMPT TO SWAP THE ARGS.
IF CAN DO SO, THE PERFORM OP IN LHS REG***)%
IF .RHNODE[ARG2PTR] EQL .LHNODE
THEN
BEGIN
IF COMMUTATIVE(RHNODE)
THEN
BEGIN
SWAPARGS(RHNODE);
SETRHRGTOLH();
CMPNODINLH(.RHNODE);
RETURN TRUE;
END
ELSE
RETURN FALSE
END;
%(***SEARCH DOWN ONE LEVEL ONLY FOR REFERENCES TO LHS.
THUS CAN HANDLE:
A=A+C
A=A+B+C
A=A*B+C*D
BUT NOT:
A=A*B+C*D+E*F
A=A+B+C+D
****)%
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
%(***IF EITHER OF THE ARGS WILL BE IMPOSSIBLE TO REFERENCE IF THE
OTHER ARG IS COMPUTED INTO THE REG HOLDING THE LHS VAR,
THEN GIVE UP. (EG I=I*J+K(I) CANNOT BE COMPUTED BY COMPUTING
I*J IN THE REG FOR I)
*****)%
IF .ARG1NODE[RESRFFLG] AND .ARG2NODE[RESRFFLG] AND .RHNODE[OPRCLS] NEQ SPECOP
THEN
BEGIN
IF MUSTSAVLHREG(.ARG1NODE) OR MUSTSAVLHREG(.ARG2NODE)
THEN RETURN FALSE
END;
IF .ARG1NODE[OPRCLS] EQL ARITHMETIC OR .ARG1NODE[OPRCLS] EQL BOOLEAN OR .ARG1NODE[OPRCLS] EQL SPECOP
THEN
BEGIN
IF .ARG1NODE[ARG1PTR] EQL .LHNODE
THEN
BEGIN
IF CLOBBNX(.ARG1NODE) THEN RETURN FALSE;
CMPRHINLH();
RETURN TRUE;
END
ELSE
IF .ARG1NODE[ARG2PTR] EQL .LHNODE
THEN
BEGIN
IF COMMUTATIVE(ARG1NODE)
THEN
BEGIN
SWAPARGS(ARG1NODE);
CMPRHINLH();
RETURN TRUE;
END;
END;
END;
IF NOT .RHNODE[A2VALFLG] AND COMMUTATIVE(RHNODE)
THEN
BEGIN
IF .ARG2NODE[ARG1PTR] EQL .LHNODE
THEN
BEGIN
IF CLOBBNX(.ARG2NODE) THEN RETURN FALSE;
SWAPARGS(RHNODE);
RHNODE[RVRSFLG]_NOT .RHNODE[RVRSFLG]; !WHEN EXCHANGE ARG1 AND ARG2
! COMPUTE THEM IN THE ORDER
! ORIGINALLY DETERMINED
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
CMPRHINLH();
RETURN TRUE;
END
ELSE
IF .ARG2NODE[ARG2PTR] EQL .LHNODE
THEN
BEGIN
IF COMMUTATIVE(ARG2NODE)
THEN
BEGIN
SWAPARGS(ARG2NODE);
SWAPARGS(RHNODE);
RHNODE[RVRSFLG]_NOT .RHNODE[RVRSFLG]; !WHEN EXCHANGE ARG1 AND ARG2
! COMPUTE THEM IN THE ORDER
! ORIGINALLY DETERMINED
ARG1NODE_.RHNODE[ARG1PTR];
ARG2NODE_.RHNODE[ARG2PTR];
CMPRHINLH();
RETURN TRUE;
END
END
END;
RETURN FALSE;
END;
END
ELUDOM