When handling the $signed/$unsigned system functions, the compiler
was applying the new signed/unsigned property to the NetExpr object
representing the input argument. This caused the input argument to
be evaluated incorrectly. This patch fixes this by applying the new
property to the NetExpr object created to pad the result to the
required size.
In testing this fix, it was also discovered that the width of the
input argument expression was not being calculated correctly. This
patch also fixes this issue.
Creation of implicit nets requires knowledge of whether an identifier
has been declared before it is used. Currently implicit nets are
created during elaboration, but by this stage the order of declaration
and use is not known. This patch moves the creation of implicit nets
into the parser stage.
Under some situation the optimized repeat expression can get out
of sync while it is being processed this causes the code to
reference freed memory. This happens when the repeat expression
is converted to an unsigned integer, but the repeat expression
is used in a different path. It was easier to just remove the
optimization then track down the convoluted call sequence that
was causing this and then figure out what needed to be fixed.
The repeat expression must be constant, so is likely not too
complicated so this optimization is very minor and should not
be missed.
This patch is a major rewrite of the indexed part selects (+: and -:).
It made the following enhancements:
1. Make indexed part selects work correctly with both big and little
endian vectors.
2. Add a warning flag that warns about constant out of bounds/or 'bx
indexed selects.
3. Moved the -: parameter code to its own routine.
4. Added support for straddling before part selects in a CA.
5. Added more assert(! number_is_unknown) statements.
6. Add warning for &PV<> select with a signed index signal that is
less than the width of an int. This will be fixed later.
7. Add support for loading a 'bx/'bz constant into a numeric register.
8. Add a number of signed value fixes to the compiler/code generator.
9. Major fix of draw_select_expr() in the code generator.
In 1364-2005 it is an explicit error to take the select of a scalar
or real value. We added the checks for real a while ago. This patch
adds the functionality for scalar values. In the future we may want
to push the scalar property to the run time.
Only sign extend the operands for division or modulus if
both of them are signed. Previously only the individual
operand signedness was being considered.
This patch fixes the following problems in the right shift code.
The >>> result is only signed if the l-arg is also signed.
The r-arg is always unsigned.
Only sign extend the l-arg when the >>> operator is used.
This relates to an optimization for certain constant shifts.
Removed some obsoleted/outdated code.
This patch adds messages in various places to warn that constant
user functions are not supported. It uses a global variable to
indicate when we are in a constant context. This is a bit of a
kludge, but works well without needing to change a bunch of code.
It is interesting to note that ports are elaborated late enough
that if we had the constant function evaluation code they would
evaluate correctly. This also applies to the function return
range, the concatenation repeat, specparams and initial values.
Signal definitions are early enough that elaboration is what is
failing because the function body is not available (has not been
elaborated). The same thing applies to both parameters and
localparms.
It is possible for an identifier to have multiple index expressions.
(For example, a part select of a memory word.) Make sure all the
index expressions are probed for width and type.
And also, note that the unary ! returns BOOL or LOGIC, not just
the type of its operand. It is slightly different from the other
unary operators in that way.
The test_width for repeat-concatenations is tricky because it
requires the evaluated value for the repeat expression. It should
be OK to call elab_and_eval on that expression even during the
test_width for the containing expression. We'll see.
This patch adds logical support for real values (!, && and ||). It
also prints an appropriate error message when a real value is
incorrectly given to an operator that does not allow real arguments
(bit-wise, reduction, shift and repeat/concatenation).
For most cases just using the value of a parameter is fine, but
a vpi call can access more than the value so we want to use a
parameter reference instead of the value for vpi calls.
Strings were working correctly, integer values need some minor
code generator changes and real values needed to be pushed from
elaboration to the code generators. I also changed the default
real value comment from %g to %#g so that it is more obvious
that the value is a real value.
When doing right shift of unsized expressions, pad the left operand
so that the right shift does not lose. This better accounts for the
lossless expectations of unsized arguments.
Part selects need to be fully defined. If not, then the resulting
expression is 'bx no matter what. The same for bit selects, when
the bit select expression is constant.
When the parameter up index was being reworked someone mistakenly
used the pointer value instead of the actual value in the MSB/LSB
comparison. This obviously could give incorrect results.
This fixes up the elaboration of binary expressions found in
parameter expressions. Parameter expressions are special because
they elaborate early, before all the other parameters are necessarily
completed.
This patch fixes fully out of range constant indexed part selects
to just return 'bx. It also adds support for constant undefined
base values which also just return 'bx.
A bug in the bit width calculation when building an unsized, signed
negative integer value was also fixed (-3 needs 3 bits not 2, etc.)
The power (**) and shift operators are different from other binary
operators because their expression width calculations rely only on
their left operand, with their right operand self-determined. Get
the handling of these operators out of the PEBinary base class to
prevent confusion.
unary expressions that have problems should not assert in the
test_width method. Instead, let the error propagate back and be
handled during expression elaboration. This found a few places
where expression widths/types weren't probed before elaboration.
When padding a signal or when creating a local signal the file and
line information should be related to where the new object was
created not the signal value it is being created from.
This patch modifies the NetE* pad_to_width() routines to take a
LineInfo object to set the location to the correct value.
It fixes some set_line() calls to use the correct location.
It fixes ports to not set the file/line information if it is
already defined. Doing this was causing the definition of
signals to become the instantiation instead of the real
module declaration.
If one of the arguments of a comparison expression has a real value, then
the expression with is 1 no matter the width of the other argument. This
means that the arguments may have different widths in this special case.
Patch is from pr2251119, suggested by Martin Whitaker.
Even though we cannot immediately give a width for a concatenation
that has a repeat expression (the expression must be evaluated first)
we still must scan the test_width of the arguments so that they can
resolve their types.
This includes enough API to get the branch nexus bits and signals
and show them in the dump. This also includes creating the reference
ground for branch access functions that use the implicit ground.
The natures of disciplines were already available, this just brings
the information forward to the ivl_target.h API and exposes them via
access functions.
Signals may have VMA disciplines attached. Make the attached discipline
visible through the ivl_target.h API. Also, re-arrange the internal
handling of the discipline structure so that we can expose disciplines
through the ivl_target C API without creating new structures. The
t-dll-api implementations of the discipline access functions can look
at the elaborated discipline structure directly. This is possible since
the discipline parse and elaboration are very simple.
Martin Whitaker
Cary R
Larry Doolittle
Stephen Williams