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.# Addendum --- vcg now puts out binary directly
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.CH ADDENDUM
.sp
.ce
Arnold D. Robbins
.sp
.ce
August, 1984
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.MH Introduction
With the second release of the
Georgia Tech C Compiler, 'vcg' has been changed in two ways.
This addendum describes those changes.
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.MH "Object Code Produced Directly"
'Vcg' has been changed to directly
generate 64V-mode relocatable object code, instead of
symbolic assembly language.
This [ul enormously] speeds up code generation time, since
the Prime Macros Assembler, PMA, is no longer needed to turn
the assembly code into binary.
.pp
As an option, 'vcg' will still produce PMA, which can be
assembled normally.  This is occasionally useful, since
the object code routines still have some bugs buried deep
within them.
.# we just don't have the expertise, the time, or the desire to
.# try and dig them out.
See the help on 'vcg' for details on producing assembly code.
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.MH "Shift Instructions"
Whenever a shift instruction is needed, 'vcg' used to generate code
to build an instruction and then XEC it.
Now, 'vcg' will generate a shortcall into a table of shift instructions.
This table is included in the "vcglib" library, and in the "ciolib"
library for C programs.
This change saves code space for programs with a lot of shift
instructions.