Icarus uses 'i' in the net expressions for a cast to integer. Replacing
it with 'v' would free the character 'i' that can be used for increment
operators. This changes cast operators to become 'v', '2', and 'r'.
Signed-off-by: Prasad Joshi <prasad@canopusconsultancy.com>
Suggested-by: Cary R. <cygcary@yahoo.com>
This patch adds code to the compiler so that a constant string
in a structural context can maintain the string property. This
is needed but not currently implemented in vvp (it's still
converted to a number). A pending patch for the vlog95 target
does use this new information.
This patch allows the compiler to perform early elaboration
of functions if they are encountered in expressions that are
elaborated before the function would normally be elaborated.
This makes the function available for constant evaluation.
Suitable error messages are generated if a function that is
used in a constant expression is not a valid constant function.
This patch adds code that allows the targets to determine if a logical
gate came from a continuous assignment. This helps some of the targets
generate code that more closely matches the input.
It also reworks/simplifies the synthesis of && and || since the
compiler has already converted the two operands to single bit form
and fixes a mismatched delete from a previous patch.
It was documented that ivl_scope_port(s)() could be used with tasks,
but the code did not support this. This patch adds that functionality
as documented. It also removes the documentation for ivl_lval_mem()
since that function no longer exists.
BOOL values have a specific cast from LOGIC, this node takes care
of it. Also arrange for the elaboration to insert them in the right
planes and for the code generator to generate them.
SystemVerilog allows variables to be either variables or unresolved
nets, depending on how they are used. If they are assigned by
procedural code, then they are variables. If they are assigned
by a continuous assignment, they are unresolved nets. Note that
they cannot be both, and when they are unresolved nets they can
only be assigned once.
This patch adds the ability to call a system function as a task for
the SystemVerilog generation (-g2009). The return value is really
calculated, but it is ignored.
Elaborate conditional assignments with BUFZ devices that do *NOT*
preserve strengths. Add a BUFT (transparent) device that can be
used in those cases where I really need a transparent buffer.
A real delay must be scaled and rounded using the local precision
before it is finally scaled to the simulation time units. This
patch fixes the compiler to do this correctly or generate the
correct code for run time calculated delays. Delays in a CA
already worked correctly. The run time was also fixed to scale
modpath (SDF back annotation) delays correctly.
Some new shadow issues have crept in. This patch fixes these new
issues and adds -Wshadow to the normal warning flags to keep any
new occurrences from happening.
This patch cleans up some style issues: no need to check that a value
is defined before freeing or deleting it, use C++ style casts, make
sure to NULL terminate strncpy(), empty() is faster than size() for
size == 0 or size >= 0 checks, re-scope some variables, etc.
The Cygwin compiler is a bit picky. This patch adds some casts
to remove compilation warnings. In the past I have had warnings
off because of problems with the STL, but for this directory we
mas as well remove the warnings we can. It also does not
recognize that an assert(0) or assert(false) ends a routine so
it complains about no return at end of function or variables
not being defined.
It turns out that although there was all kinds of code to manage
these members, there were no uses anywhere. It must have been a
legacy from a previous era. So remove the dead code so that it
doesn't confuse me again.
Remove some wasteful and excess scans of the Nexus of some links,
and remove dead code so we can see what we're doing. Also inline
some commonly used and trivial functions.
Once code generation starts, the Nexus structure no longer needs to
support fast insertion/connect operations. So have the code generator
lock down the Nexus structures and adjust the Link lists for optimal
access during readout.
If a signed signal is driving a part select in a CA and the width
is less than 32 bits. the value will be zero extended and will
not work for negative values. This patch adds a warning that this
could happen. This will be fixed in development.
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.
This patch adds -g2001-noconfig command line flag. The compiler
already supported this with `begin_keywords. Document this in
the manual page and fix a few other issues.
Fix endgenerate to be a 2001 keyword and add a few missing
keywords at the appropriate standard level e.g.(unsigned).
Add uwire and deprecate wone. wone used to just convert without
a warning to a wire. uwire will display a warning that it is
being converted to a wire without a check. wone is converted to
a uwire with a warning and then prints the uwire message. The
uwire message will be replaced with a real check fairly soon.
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.
When a pin array is virtual, dll_target::signal() doesn't need
to make a corresponding set of stub nexa.
This patch includes new detection of oversized arrays, configurable
with the ARRAY_SIZE_LIMIT flag. This limit only applies to devirtualized
arrays; virtual arrays are only limited by your architecture's
unsigned int type.
The concept and earlier versions of this patch have been successfully
stress-tested by multiple people. This one causes no testsuite
regressions on my machine.
Closes: pr2023076
Reduces resource usage when compiling large memories.
Normal usage patterns still create large nexus arrays
in t-dll.cc:dll_target::signal().
This patch is extensively tested; it shouldn't break anything.
The existing debug "optimizer" flag is (ab)used to control
message printing when large (>1000 element) arrays are
devirtualized or nexus-ized.
The new global variable disable_virtual_pins is available
to force allocation of Pin arrays when they are declared,
but no user interface is provided.
See extensive discussion on iverilog-devel, March 4-5 2009,
title "pr2023076: large memories".
Limit memory sizes to whatever fits in unsigned; crash if
the conversion from unsigned long to unsigned overflows,
instead of just wrapping. I don't know what happens on
a 32-bit machine if you ask for an 8 Gig memory, but with
a 64-bit machine and this patch, it crashes with an assert.
Set direction on PartSelect Links before connecting them.
May or may not be considered orthogonal to upcoming
memory virtualization patches.
Previously Icarus normalized the results so array [7:0] would
be the same as array [0:7]. This works just fine for
simulation, but the VPI calls can select the left or right
value and this was incorrect for the [7:0] case since it was
being normalized to [0:7]. This patch swaps the two values in
the a.out file and from this creates the previous first/last
values and a new flag that can be used to get the correct
left and right values for the VPI interface.
Seemingly does nothing, just refactors to create two new methods:
bool NetPins::is_linked(void)
void NetNet::initialize_value_and_dir(verinum::V init_value, Link::DIR dir)
and rearranges netlist.h.
This patch causes no regression in the testsuite.
It smooths the way for any attempt to address pr2023076.
Finish cleaning up shadowed variables, flagged by turning on -Wshadow.
No intended change in functionality. Patch looks right, and is tested
to compile and run on my machine. No regressions in the test suite.
This is the end of the simple, coordination-free patches.
The remaining shadows are special cases that will need extra attention.
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.
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.
Now that NetNet objects in NetScopes are kept in a map, remove the
linked list for scanning them. This improves the lookup process from
an O(e**N) process to more like O(log(N)). This matters for very
large designs.
Get at least basic elaboration of analog processes and contribution
statements. Bring the statements and analog statements together and
net future elaboration work sort out which statements are valid in
a given context. This makes sense because there really is a lot of
syntactic overlap, and analog behavioral code is processed somewhat
sequentially.
Put together the infrastructure for elaborating analog statements,
including create the NetAnalogTop objects that hold analog statements
and are in turn held by the design.
While doing this, clean up the various unique initial/always enumerations
to use the ivl_process_type_t type.
The signedness of comparison expressions is typically unsigned, even if
the comparison to be performed is signed. The comparison (and particularly
the expr_synth of the comparison) needs to account for this explicitly.
Start cleaning up shadowed variables, flagged by turning on -Wshadow.
No intended change in functionality. Patch looks right, and is tested
to compile and run on my machine. YMMV.
The arguments to bitwise operators are padded if *either* of the operands
is unsigned. This is according to the sign/unsigned expression rules
of Verilog, and also matches the behavior of the "Big-3."
The addition of UINT_MAX in netlist.cc requires #include <climits> when compiling with gcc-4.3.2.
I also noticed that commit 8704e3e used c style includes in c++ sources contrary to the style used in the rest of the c++ code and fixed those.
Remove redundant pointer to the containing NetPins object by keeping
the pointer only in the first Link (pin 0) of an array of links. In
this link, replace the pin number with the NetPins pointer, and set
a pins_zero_ flag to indicate that this has happened. This way, only
the first pin in a Link array will have the pointer to the NetPins
that contains the array, and the pointer takes up practically no space
at all.
This class was old, and its original design pulled literally from
the LPM reference. But of nine pins declared, only 4 were used.
Remove all the excess junk and clean up the designed dump handling
of the device.
This patch moves the always zero or possibly zero delay checks
to a point after the circuit is full elaborated. Before it
could try to check tasks that had not already been evaluated
resulting in a crash.
When looking for a delay_type() in a block stop when we have a
DEFINITE_DELAY. Doing this could reduce the number of statements
that need to be checked.
It is legal for a task to have no definition. In that case, the
delay_type calculations (used to detect infinite loops) can assume
that an empty definition is a no-op and return NO_DELAY.
The NetBranch object is connected, but not like an object, so the
NetPins object base class is factored out from NetObj to handle the
connectivity, and the NetBranch class uses the NetPins to connect a
branch.
Also, account for the fact that nets with a discipline are by default
real-valued.
This patch adds .cast/int and updates .cast/real to act as a local
(temporary) net and to support either a signed or unsigned input.
The vvp_vector4_t class not can convert an arbitrarily sized double
to a vector value. This removes the restriction of lround().
Also document the new statements.
This handles the general case of a non-real operand to a real-valued
division. This can turn up if only 1 operand of a divide is real. In
this case the division as a whole is real and the other operand must
be cast to real.
This method creates an extra node, but it should be a very compact
node and this node does no evaluation tricks so in the run time should
be no more expensive then folding the cast into the .arith/div.r itself.
The Verilog LRM specifies that it is legal to give constant part
selects that are beyond the bounds of the identifier being selected.
But elaboration was flagging that as an error. This patch changes it
to a warning, and handles the cases by generating 'bx bits as needed.
In continuous assign expressions, the abs() operator can't easily be
burried in generic unary handling, so add the IVL_LPM_ABS type and
generate it as needed.
Implement in behavioral the abs/min/max operators for real values.
The parser treats these builtin functions as operators, unary or
binary, and elaborates them appropriately.
Also add enough code generator support to handle real valued expressions
in thread context.
This patch adds ifnone functionality. It does not produce an
error when both an ifnone and an unconditional simple module
path are given. For this case the ifnone delays are ignored.
This patch adds check to determine if an always block has delay
in it or not. If there is no delay a runtime infinite loop will
occur. For the indeterminate case it will print a warning message
if the new -Winfloop flag is given. This flag is not part of the
-Wall check!
This patch fixes some allocation problems (mostly in the parser
and lexor relating to identifiers). It also fixes a couple places
where uninitialized variables were used. All found with valgrind.
There are still 100 tests that have problems. Many of these appear
to be related.
This patch reworks much of the ternary code to short circuit when
possible and supports real values better. It adds a blend operator
for real values that returns 0.0 when the values differ and the value
when they match. This deviates slightly from the standard which
specifies that the value for reals is always 0.0 when the conditional
is 'bx. There are also a couple bug fixes.
These fixes have not been ported to continuous assignments yet.
Ternary operators used at compile time and in procedural assignments
should be complete (short circuit and support real values).
Addresses pr1879226 on a couple of levels. Analysis:
NetNet* PEBinary::elaborate_net_shift_() didn't flag dist==lwidth
as a case where all bits of the input are shifted away, which made
it create a real concatenator for this case. It attempted to create
NetNet*tmp with zero width, which doesn't work; (lsb,msb) ends up
as (0,-1), which is later interpreted as a 2-bit wide net.
Added an assert to the NetNet constructor to catch any other lurking
attempts to create zero-width nets.
Added short-circuit code to handle the case where all bits of the input
are shifted away. This case used to be "handled" by an assert failure.
The nodangle functor tries to delete NetNet objects that are not used.
But NetNet objects that are addressed by a NetArrayDq should never be
dangling. So make sure the NetArrayDq marks the target NetNet correctly.
Rework the handling of file names to use a perm_string heap to hold
the file names, instead of the custom file name heap in the lexor.
Also rename the get_line to get_fileline to reflect its real duties.
This latter chage touched a lot of files.
When evaluating bitwise binary expressions at compile time, get the
signed/unsigned padding correct. Pay special attention to the case
of $signed/$unsigned changing the signedness of the operand.
Real value are vector width of 1, fix real literal to reflect this.
fix leaking real registers in code generation for function arguments.
Load of signal should handle conversion from real to vector. Function
arguments, type vector passed a real value, are an example where this
comes up.
Signed-off-by: Stephen Williams <steve@icarus.com>
Stephen Williams
Cary R
Prasad Joshi
Martin Whitaker
Larry Doolittle
Jared Casper
Martin Whitaker
steve