Enter your search terms Submit search form
	Web pdp-10.trailing-edge.com

* -*- TRANSFORT FORTRAN -*-
*  TRANSFORT v1.5 1-Mar-86

*	FORTRAN program to illustrate each transformation performed
*	by TRANSFORT.
* 
*	10/21/85	jke
* 
	PROGRAM TTEST

*	TRANSFORM 1
* 
*	DEC-20 FORTRAN allows comment lines to begin with several characters
*	the VAX does not allow.  The translated program has all comment lines
*	beginning with an asterisk.

*	This comment line begins with C
*	This comment line begins with c
*	This comment line begins with $
!	This comment line begins with !
*	This comment line begins with /

*	TRANSFORM 2
* 
*	Statements on multi-statement lines are separated so that each
*	is contained on its own individual line.  A statement label is
*	associated with the first statement on the line, and a "!"
*	comment is associated with the last.

10	A=B
	CONTINUE
	IF (A.EQ.3) 20, 30, 40	! If statement is last

*	TRANSFORM 3
* 
*	Identifiers longer than 6 characters are truncated to 6 characters.
*	The DEC-20 and VAX both allow longer identifiers, but they are only
*	significant to 6 characters whereas they are significant to 31 on
*	the VAX.
* 
*	In the example given, the identifiers A VERYLONGIDENTIFIER and
*	AVERYLITTLEID are considered to be the same identifier on the DEC20.
*	This transform insures that the VAX will do the same.
* 
*	This transformation generates an IDTRNC6 warning.

	LONGID=AMUCHL+AVERYL+AVERYL

*	TRANSFORM 4
* 
*	Hollerith constants used as actual arguments to subprograms are
*	detected because the bit patterns actually passed to the subprogram
*	may be different.
* 
*	This transformation generates a HOLCNSARG warning.
*	This transformation does not alter the target code.

	CALL SAMPLE(3HABC)

*	TRANSFORM 5
* 
*	Octal constants, when found, are converted to use the VAX syntax.
* 
*	This transformation generates a BITHACKAS warning.

	A='777'O

*	TRANSFORM 6
* 
*	Alternate syntax for relational operators: The symbolic forms of
*	the relational operators are converted to the standard form.

	IF (A.EQ.B) THEN	! equal
	IF (A.NE.B) THEN	! not equal
	IF (A.LT.B) THEN	! less than
	IF (A.GT.B) THEN	! greater than
	IF (A.LE.B) THEN	! less than or equal
	IF (A.GE.B) THEN	! greater than or equal

	END

*	TRANSFORM 7
* 
*	The symbolic form of the exponentiation operator "^" is converted to
*	"**".

	SUBROUTINE A
	LOGICAL LV

	SQRT(A)=A**0.5	! ^

*	TRANSFORM 8
* 
*	The precedences of unary + and - differ on the VAX and DEC.
*	Expressions involving these operators may be altered so that
*	the expressions are evaluated in the same manner.  Parentheses
*	are placed around the unary term.

	A=A*(-B)*C+D	! B * C is negated
	END

*	TRANSFORM 9
* 
*	Mixing logical and numeric values in an expression - this is
*	detected because logical values have different representations
*	on the two machines.  This also occurs during equivalence.
* 
*	This transform produces a BITHACKAS warning, a BITHACKEQ warning,
*	or a BADLOGOP warning.

	FUNCTION FN
	LOGICAL LV
	EQUIVALENCE (LV, I)

	I=.TRUE.
	LV=(.TRUE..AND.3)
	END

*	TRANSFORM 10
* 
*	The additional return label indicator "$" available on the DEC
*	is converted to "*" so it will compile on the VAX.

	SUBROUTINE TEST(A, *, B, *, C, &)	! List is (A,*,B,$,C,&)
	CALL TEST(*10, *20, &30)	! List is (*10,$20,&30)

*	TRANSFORM 11
* 
*	Two-branch IF statement converted to an equivalent 3-branch IF.

	IF (A.LE.B) 10, 20, 20

*	TRANSFORM 12
* 
*	Obsolete or untranslatable statements are flagged.  These statements
*	include DECODE, ENCODE, PUNCH,

	DECODE (A, B, C)
	ENCODE (A, B, C)
	PUNCH 3
	UNLOAD 3
	BACKFILE 3
	REREAD (FMT=100) A, B, C

*	TRANSFORM 13
* 
*	Default write unit - this form of statement is illegal on the VAX.
*	TRANSFORT can, via the control file, create write statement to
*	UNIT 6 (or a user-specified unit), or ignore them.
* 
*	This transformation produces a WRTUNTMOD warning.
	WRITE (UNIT=6, FMT=10) A, B, C
	WRITE (UNIT=6, FMT=*) A, B, C

	END

*	TRANSFORM 14
* 
*	FMT specification of a namelist - FMT is converted to NML.

	FUNCTION WRTTST

	NAMELIST /AAA/B,C,D
	DIMENSION BBB (10)
	CHARACTER BBB
	COMMON A, B, C, D, E

	WRITE (3, NML=AAA)	! FMT should be changed to NML
	WRITE (3, FMT=BBB)	! This one should not be

*	TRANSFORM 15
* 
*	Default field widths for edit descriptors I,F,E,D,G,O,Z,L, and A
* 
*	This transform produces a BDDFLTFMT warning.

100	FORMAT (X, I, F, E, D, G, O, Z, L, A)

*	TRANSFORM 16
* 
*	R-Hollerith Edit Descriptor is converted to A edit descriptor.
* 
*	This transformation produces a warning.

110	FORMAT (X, 3A5)

*	TRANSFORM 17
* 
*	Argument passing: because of the different methods used, certain
*	situations can cause different results to occur from the same
*	code ont he two machines.  TRANSFORT attempts to warn about
*	these situations.
* 
*	This transform produces a COMPARM warning or a VARUSED2 warning.

	CALL SUB(A, E, E)
	X=1+FN(E,A,E)

*	TRANSFORM 18
* 
*	Assigned GOTO statement.  Since the VAX ignores the list of labels
*	in the statement, these statements are detected.
* 
*	This transform produces an ASGOTOLST warning.

	GO TO LV (10, 20, 30)

*	TRANSFORM 19
* 
*	Unit 5 for output.  Like the default output unit, unit 5 WRITES can
*	be altered to unit 6, a user-defined unit, or ignored.  This is
*	provided because the DEC allows input and output both using unit 5,
*	but the VAX does input from unit 5 and output from unit 6.
*	(Terminal I/O)
* 
*	This transform produces a WRTUNTMOD warning.

	WRITE (6, *) A, B, C
	WRITE (UNIT=6, FMT=*) A, B, C

*	TRANSFORM 20
* 
*	OPEN STATEMENT QUALIFIERS

	OPEN (5, STATUS='NEW')

*	TRANSFORM 21
* 
*	CLOSE STATEMENT QUALIFIERS

	CLOSE (5, DISPOSE='DELETE')

*	TRANSFORM 22
* 
*	The final X edit descriptor of a format statement is replaced with
*	a blank character.
* 
*	This transform produces a BADFRMTNX warning.

120	FORMAT (X, 3I5, 10(' '))
130	FORMAT (X, 3I5, ' ')
140	FORMAT (' ')

*	TRANSFORM 23
* 
*	Floating point descriptors with empty decimal field widths are
*	converted to explicitly indicate an empty decimal field.
* 
*	This transform produces a warning.

150	FORMAT (X, F5.0, E5.0, G5.0, D5.0)

*	TRANSFORM 24
* 
*	Quoted strings as actual arguments are detected because the bit
*	patterns actually passed to the subroutines may differ.
* 
*	This transform produces a CHRCNSARG warning.

	CALL SUB('A')
	X=VAL('123')

*	TRANSFORM 25
* 
*	Mixing numbers and quoted strings: Again, due to differing bit
*	patterns, these are detected and warned about.
* 
*	This transform produces a BITHACKAS warning or a BADRELOP warning.
	A='ABC'
	IF (A.LE.'3') 10, 20, 20

*	TRANSFORM 26
* 
*	A edit descriptor - detected due to number of A items which appear
*	per word - 5 on DEC but only 4 on VAX.
* 
*	This transform produces a SZMSMTCHF warning.

160	FORMAT (X, A5)

*	TRANSFORM 27
* 
*	DO Loops may be converted to execute once if the ONE-TRIP flag is
*	set (ONE-TRIP appears in the control file).  Order of expression
*	evaluation is insured.
* 
*	This transform produces a ONETRIP warning.

	DO 10 I = 1,2,3
	DO 10 J = A,B
	DO 10 K = A,FN(3)
	DO 10 L = A,FN(3),B

*	TRANSFORM 28
* 
*	Program format: Look above!