Named libraries are similar to the work library, but they are not
written to implicitly, or imported implicitly. They are only brought
in by a "library" clause, the the packages within the library are
brought in by a "use" clause.
Presumably, the user will want the ability to explicitly set the
working library location, so create a +vhdl-work+ plusarg setting
for exactly that purpose.
Port map aspects were held in std::maps. Because
of that, in case of multiple assignments to the same
port, some assignments were lost and in effect vhdlpp
produced correct verilog code from a buggy VHDL.
Std::map was replaced by std::multimap. Thanks to it
we can gather this multiple assignments and detect them
in the elaboration phase.
This patch introduces in ScopeBase separate containers
for declarations coming from the current scope and from
the previous scopes.
Until now, in one scope, all objects were kept in an stl map.
When a scope was created inside other scopes, a shallow
copy of the map was made. This solution was nice for
name shadowing (in new scopes, when a name was
encountered, the old objects were overridden by a new
one), but didn't allow for distinguishing where the objects
were allocated. As a result, it is impossible to know who
the owner is and who should delete them.
In this commit ScopeBase gets two containers: for old
and new objects. If a ScopeBase is made from another
ScopeBase object, all objects from the copied object
go to an old_XXX container, where XXX depends on the
type of the copied objects. When a ScopeBase object
is deleted, the objects from new_XXX are deleted and
the ones from old_XXX are not touched.
This patch adds some complexity to the internals
of ScopeBase, but leaves its interface unchanged.
This is rather a cosmetic change. The patch changes
the container used for stack of scopes from std::list
to std::stack. It suits this particular application
a bit better.
Thanks to valgrind analysis it turned out that
there were objects in the parser that were not being
deleted in a proper way. This patch fixes them all.
Instead of using automatic variables for global
types, I allocate them dynamically. Thanks to it,
all type objects can be treated in the same way,
as all of them are pointers allocated with `new'.
Now we will be able to remove all scopes in the same
manner, no matter if it is a global or local scope,
by deleting all carried pointers.
When writing arrays to the work library, handle the special
case that it is an array of std_logic and write a std_logic_vector
declaration instead. This makes for a more compact description.
When a "use" clause tries to pull a package from the work library,
put together a file name and try to find that package in the
work library directory. If found, parse the package file and
try again to find the package.
Bison and Flex generate different interfaces for reentrant
parsers, so handle that different API. We need this change
because library support is going to reuse the parser to
read in library packages.
This function is for the time being used in the
component instatiation. It is checked, whether
an expression is a correct r-value.
To be a correct r-value, it must be either
port name or signal name.
Build up a work library by writing a VHDL representation of the
package header into a source file. This representation needs to
be accurate enough that later invocations of vhdlpp can read them
with the VHDL parser.
The $ivlh_attribute_event system function helps the Verilog runtime
support <name>'event expressions in VHDL. The vhdlpp generates a
call to $ivlh_attribute_event, which in turn uses callbacks to handle
the support.
This is also the start of the vhdl_sys vpi module. This module should
by included whenever VHDL code is parsed.
When a signal (or port) is assigned by a sequential assignment,
the signal or port becomes a reg, instead of a wire(net). Detect
this distinction during elaboration and generate the correct
signal/port declaration.
Keep the entity/component/module port declarations in the module port
list of the generated code. This clarifies the generated code and
fixes a couple bugs for more complicated types.
R-value expressions are more general then L-value expressions, in that
the expression type may be a bit more complex. If the R-value expression
is part of an assignment, then elaborate with the constrained type from
the L-value. In other cases, where the expression type is not as obvious,
use expression type probes to figure out the type of the expression and
elaborate using that calculated type.
VHDL doesn't have a direct way to express "always @(posedge...)"
statements, but we do want to detect common paradigms that naturally
translate. This makes for a better translation.
Entity output ports may be used as l-values in a process within
the bound architecture. Detect that case during elaboration and
adjust the signal declaration so that it works in the Verilog pass.
Infrastructure for debug and emit of sequential statements in processes.
This does not properly handle the actual semantics of the behavioral
code, but it provides an infrastructure where we can handle all the
tricky elaboration to come.
Stephen Williams
Cary R
Pawel Szostek