The compilation unit scope is now treated as a specialised form of
package (with an automatically generated name). All items declared
outside a design element are added to the current compilation unit
package. Apart from when searching for a symbol, once we get into
elaboration we can treat these just like any other package.
A compressed assignment statement should give exactly the same
result as the equivalent uncompressed statement. This means
that the type (signed/unsigned) of the LHS affects the type of
the RHS expression (unlike in normal assignments). We need to
take care that bit/part selects and concatenations are correctly
identified as unsigned values, even in the cases where they
reduce to a single whole signal.
Synthesis could only handle relatively simple conditional constructs.
This rework aims to make it handle anything the user can throw at it
(or output a sensible message as to why it can't).
Changes so "Microsoft Visual Studio Express 2015 RC Web" could build it without a bunch of runtime errors and crashes during regression testing. When declaring an bitfield variable of type enum in a struct, the enum has to have an underlying integer type for MSVC++ when compiling a C++ file, and for these cases, it had to be unsigned integer for everything to work okay during regression testing.
When unsized literals are used in case item expressions, it is likely
that the calculated expression width will be larger than necessary to
unambiguously select the correct case item (particularly when using
"strict" expression elaboration). This patch adds an optimisation
step that prunes the expressions to the minimum necessary width.
This patch fixes the following enumeration bugs:
When looking for an enumeration look in the current scope and then
recursively in any parent scope.
Add enumeration definitions to a package scope.
Internally, treat the "$" as a special expression type that takes
as an argument the signal that is being indexed. In the vvp target,
use the $last system function to implement this.
Like this:
... if (ce0) foo <= foo_in;
... if (ce1) bar <= bar_in;
Note that this is within a block, and represents multiple FF nodes
with different clock enables.
When for example assigning to foo[<x>] within a contitional, and
doing synthesis, we need to create a NetSubstitute device to manage
the l-value bit selects.
Cary R
Martin Whitaker
Henry Wong
Michele Castellana
Larry Doolittle
Stephen Williams
Johann Klammer
Christian Taedcke
Frederick C. Kurz
Martin Whitaker