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XNF synthesis now uses the synth functor.

This commit is contained in:
steve 1999-11-03 05:18:18 +00:00
parent b66e7b1713
commit b3afc108cf
1 changed files with 12 additions and 9 deletions
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21
xnf.txt
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@ -101,15 +101,15 @@ line. The code generator needs to know the type of part to generate
code for, so the ``-fpart=<type>'' flag is also needed. For example, code for, so the ``-fpart=<type>'' flag is also needed. For example,
to generate code for the 4010E the command line might start out as: to generate code for the 4010E the command line might start out as:
ivl -txnf -fpart=4010e -Fxnfsyn -Fsigfold -Fxnfio [...] ivl -txnf -fpart=4010e -Fsynth -Fsigfold -Fxnfio [...]
Icarus Verilog includes the functions ``xnfsyn'' and ``xnfio'' to Icarus Verilog includes the functions ``synth'' and ``xnfio'' to
perform transformations and optimizations on the design before code is perform transformations and optimizations on the design before code is
generated. The xnfsyn function matches certain behavioral constructs generated. The ``synth'' function matches certain behavioral constructs
to XNF components, and the xnfio function generates pads and fills the to structural components, and the xnfio function generates pads and
IOBs. fills the IOBs.
XNFSYN FUNCTION THE SYNTH FUNCTION
This function does synthesis transformations on the entered design, This function does synthesis transformations on the entered design,
making it possible to generate XNF netlist components from certain making it possible to generate XNF netlist components from certain
@ -117,13 +117,13 @@ behavioral constructs. This is needed in Verilog for example to model
some of the synchronous components of the XNF library. some of the synchronous components of the XNF library.
It is a bit much to expect a Verilog compiler in general to generate It is a bit much to expect a Verilog compiler in general to generate
components from arbitrary behavioral descriptions, so the xnfsyn components from arbitrary behavioral descriptions, so the synth
function works by matching statements that have some documented function works by matching statements that have some documented
structure, and substituting them for the equivalent XNF component. A structure, and substituting them for the equivalent XNF component. A
fully synthesize-able design, then, is one where the behavioral fully synthesize-able design, then, is one where the behavioral
statements can all be matched and substituted by the xnfsyn function. statements can all be matched and substituted by the synth function.
XNFIO FUNCTION THE XNFIO FUNCTION
The "xnfio" function transforms the netlist where the IOBs are The "xnfio" function transforms the netlist where the IOBs are
concerned. The signals with PAD attributes are checked, and concerned. The signals with PAD attributes are checked, and
@ -162,6 +162,9 @@ IBUF, NOT gates cannot be absorbed as in the OPAD case.
$Log: xnf.txt,v $ $Log: xnf.txt,v $
Revision 1.7 1999/11/03 05:18:18 steve
XNF synthesis now uses the synth functor.
Revision 1.6 1999/11/02 01:43:55 steve Revision 1.6 1999/11/02 01:43:55 steve
Fix iobuf and iobufif handling. Fix iobuf and iobufif handling.