This implementation works by detecting assignments
to constant properties in elaboration. Allow initializer
assignments to assign to the constant, error all other
assignments, and otherwise treat the constant like any
other property.
Class constructors are the "new" method in a class description.
Elaborate the constructor as an ordinary method, but the only
way to access this method is to implicitly call it. The elaborator
will take the constructor call and generate a naked "new" expression
and implicit constructor method call with the object itself as the
return value.
Rework lexical support for PACKAGE_IDENTIFIER so that the lexor
can help with package scoped identifiers.
Pform package types and package functions up to elaboration.
This patch adds support for bool/bit vector types on the LHS of
a parameter declaration and ensures implicit casts in parameter
declarations are performed where necessary.
A package can have parameters, but it does not have specparams or
keep the order the parameters are defined. This patch skips these
items if the scope is not a Module.
This was temporarily implemented to just copy definitions to the
local scope, but the better method is to create a PEIdent that has
the package attached to it.
The parser does not distinguish between module and UDP instances, so
a UDP delay is handled by the rules used for parsing module parameter
overrides. Although these rules had been relaxed to accept the case of
a simple decimal value (e.g. #10), they did not allow a simple real
value (e.g. #0.1).
Implement through the ivl core to the ivl_target.h API.
Also draft implementation of creating and storing arrays
in the vvp runtime and code generator.
In vvp, create the .var/str variable for representing strings, and
handle strings in the $display system task.
Add to vvp threads the concept of a stack of strings. This is going to
be how complex objects are to me handled in the future: forth-like
operation stacks. Also add the first two instructions to minimally get
strings to work.
In the parser, handle the variable declaration and make it available
to the ivl_target.h code generator. The vvp code generator can use this
information to generate the code for new vvp support.
The parser had been changed to support null statements in sequential
and parallel blocks (a feature introduced in SystemVerilog), but was
not supported in elaboration, leading to a compiler crash. This patch
fixes this by discarding the null statements during parsing.
Making the scope type NESTED_MODULE was just plain wrong, because
it didn't really encapsulate the meaning of program blocks OR
nested modules. So instead create nested_module() and program_block()
flags and use those to test scope constraints.
An important advantage of program blocks is its ability to nest
within a module. This winds up also allowing modules to nest, which
is legal but presumably less used feature.
This patch extends the compiler to support all specparam declarations
allowed by the 1364-2005 standard. For compatibility with other
simulators, it allows specparam values to be used in any constant
expression, but outputs a warning message and disables run-time
annotation of a specparam if it is used in an expression that must
be evaluated at compile time.
This is a cleanup in preparation for better support of range lists.
(cherry picked from commit 8f7cf3255acad55841f8b3725e3786ef49daad68)
Conflicts:
PTask.h
elab_scope.cc
elab_sig.cc
parse.y
pform.cc
pform.h
pform_types.h
Signed-off-by: Stephen Williams <steve@icarus.com>
The SystemVerilog unbased literals (e.g. '0, '1, etc.) are expected to be
used standalone and cannot take a size. This patch modifies the parsing
code to give a good error message when this is done.
Class methods belong in a class scope, not the containing module.
So create a lexical scope that carries tasks and functions and
create a PClass to represent classes.
Tasks call arguments may be dropped in favor of default values.
Allow for that in the syntax. This requires a little handling
of the non-SystemVerilog case during elaboration.
Class names can be declared early, before definitions, so that the
name can be used as a type name. This thus allows class definitions
to be separate from the declaration. This creates some complexity in
the parser, since the lexor knows about the class names.
This adds the vector_type_t and real_type_t types to handle
vector and real types in tf_port items. This cleans up a lot
of the parsing for these items.
During parse/pform processing, convert increment statements to
the equivalent compressed assignment statement. This is less weird
for elaboration processing and better expresses what is going on.
This gets me to the point where the parser stashes a defined type,
and the lexical analyzer uses the type names to differentiate
IDENTIFIER and TYPE_IDENTIFIER.
Parse typedefs with structs and enums, but give a sorry message,
because they are not yet supported. Rearrange some of the parse
rules for variables in order to increase comonality with the
typedef rules.
The standard allows a parameter (or localparam) declaration of the
form "parameter signed my_param = ...". The parser currently rejects
this. A small adjustment is also required in the parameter evaluation
code to correctly apply the type.
This patch adds wreal support when in Verilog-AMS mode. It doesn't add
everything that is shown in the Verilog-A standard.
It adds the following:
Declaring a wreal net.
Declaring a wreal net with an initialization.
Declaring a wreal input/output using ANSI syntax.
Declaring a wreal input/output using the old style.
Declaring wreal inout ports are also allowed and parsed, but the
compiler does not know how to handle this. There are other deviations
from what is shown in the Verilog-A standard, but this should get most
of the syntax people actually use.
It is legal for a named block to contain variable definitions and
no statements. This patch fixes this for both style of blocks. It
also organizes the block parsing code to be a bit more clear, adds
an error case for fork/join and changes on check for size() > 0 for
the more efficient ! empty().
This patch fixes a few more bugs in the enumeration code.
It add support for saving the file and line information to make
diagnostic messages better.
It updates some of the compiler warning messages to use the file
and line information.
It passes if the enumeration type is signed all the way to the
code generators.
It fixes the parser to correctly have the range after the signed
designation for the vector types.
It adds a warning that vvp does not currently support a negative
two state enumeration value.
Add a new IVL_PR_FINAL process type.
Add a flag to NetScope in_final_ which is set when elaborating the
statement of a final procedure.
Add checks during statement elaboration for invalid statements in a
final procedure, similar to checks for statements in functions.
Do a final check to make sure no final blocks have delays.
In the vvp runtime, use "$final" as the flag for the thread created by
the final procedure. During compilation, instead of adding such a
thread to the sched_list, add it to a new schedule_final_list that
mirrors the schedule_init_list, but is run at the end of simulation.
This patch adds support for increment/decrement operators as an
expression. The operations on real and vector slices have been
disabled for now.
These operators can be used as in independent statements. However, the
corresponding support is not added in parser.
Changes since V2:
- Additional error checking in elaboration to deny operation on vector
slices and real (suggested by Martin)
Changes since V1:
- Use 'i' and 'I' for increment (suggested by Cary)
- Evaluate sub-expression once (suggested by Cary and Stev)
- Add necessary checks during elaboration to ensure that the
expression is valid (suggested Stev)
- Proper width handling with vectors (suggested by Martin)
Signed-off-by: Prasad Joshi <prasad@canopusconsultancy.com>
This patch adds code to check for a negative or undefined value used in
an enumeration sequence name, it verifies that the count in an enumeration
sequence name is not zero and allows more decimal constant values in the
enumeration sequence name..
SystemVerilog extended the assignments operator support to C-like
assignment operators and special bitwise assignment operators.
For example:
a += 1;
a -= 1;
The list of these operators can be found in SV LRM (1800-2009)
section 11.4.1.
NOTE: I fixed a few parts of this. In particular, the PEBShift
class is used for shift operators.
Acked-and-Tested-by: Oswaldo Cadenas <oswaldo.cadenas@gmail.com>
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
pow(int, int) is ambiguous since it could use the double version from
the math library or the verinum version. This patch makes it obvious that
we want to use the double version.
SystemVerilog has support for time literals. The time literal for
example #10ns, adds a delay of 10ns no matter the time unit currently
in effect. For more details please refer to
http://iverilog.wikia.com/wiki/Projects#SystemVerilog_Style_Time_Literals
Tested-by: Oswaldo Cadenas <oswaldo.cadenas@gmail.com>
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
A bit/logic output type in a module initially is defaulted to as a
variable. Depending on how they are used in the module, the type
changes accordingly.
For example
module test(output logic l);
assign l = '0;
endmodule
The variable 'l' would be promoted to a Net data type, when the
'assign' statement is encountered.
Acked-by: Oswaldo Cadenas <oswaldo.cadenas@gmail.com>
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
The module declaration should allow initialization of the bit and
logic data types.
For example:
$ cat clkgen.sv
module clkgen(output logic clk = 0, output bit p = 1);
initial begin
#200;
$display("p = %b", p);
$finish;
end
initial forever #10 clk = ~clk;
endmodule
$ iverilog -g 2009 clkgen.sv
$ ./a.out
p = 1
Suggested-by: Oswaldo Cadenas <oswaldo.cadenas@gmail.com>
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
SystemVerilog allows passing the 'bit' and 'logic' arguments to a
function. The patch adds support for parsing these function
definitions. The 'bit' data type is treated as boolean, whereas 'logic'
data type remains as logic.
Acked-by: Oswaldo Cadenas <oswaldo.cadenas@gmail.com>
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
The patch allows parsing of function definitions which do not have
explicit data type or range. The default return data type is assumed
to be reg unsigned and the default range is 0.
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
Verilog allows returning variables of 'reg' type. The icarus verilog
implicitly assumes the default returned type of the function as
'reg unsigned'. The patch allows to explicitly specify the 'reg' return
type.
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
Verilog allows user to define variables of primitive types. The patch
adds support for defining variables of type 'logic'. The data type
'logic' is the only primitive data type which supports defining ranges.
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
Verilog allows user to define variables of primitive types. The patch
adds support for defining variables of type 'bit'. The data type 'bit'
is the only primitive data type which supports defining ranges.
Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
If there are attributes attached to a module port declaration them
pform_bind_attribute() which is called from pform_module_define_port()
will delete the attribute list. They do not need to be deleted locally.
IEEE 1800-2005/9 says "each fixed-size dimension shall be represented by
an address range, such as [1:1024], or a single positive number to
specify the size of a fixed-size unpacked array, as in C. In other
words, [size] becomes the same as [0:size-1]."
This patch implements that translation in the parser. It issues a
warning when doing so when the generation flag is less than 2005-sv.
This patch adds/fixes the following:
Adds file/line information to a UDP definition.
Prints an error message if a UDP is passed signals wider than 1 bit.
A UDP should supports a range, but the compiler currently does not.
Add scope information for constants.
Fix the Icarus extension UDP table entry element 'h' to use h.
The ivl_udp_init() value is a char not unsigned.
Add FILE_NAME() for a bunch more of the ivl interface objects.
In the standard a pull device can be given both a 1 and 0 strength.
Only the appropriate one is actually used. This patch adds support
for giving both pull strength to a pull device.
This patch fixes the following problem in the compiler:
An integer task argument should be marked as an integer port.
An implicit register can be converted to either a reg or an integer.
An old style task port should default to <no type> unless reg or some
other type is provided. ANSI style is always defined. For example:
input ri;
output ro;
inout rio;
real ri, ro, rio;
should define all three task ports to be of type real.
It was a poor choice to only add -g2009 for 1800-2009 and ignore the
previous version of System Verilog 1800-2005. This patch adds a
generation for 1800-2005 and also adds `begin_keywords support for
1800-2005. The previous SystemVerilog keywords have been put under
the 1800-2005 generation and the new one from 1800-2009 have also
been added.
Cadence allows an ifnone with an edge-sensitive path. Until we understand
exactly what this is and how to implement it this patch adds a warning
that an ifnone with an edge-sensitive path is not supported.
This patch changes all the iterator code to use a prefix ++ instead
of postfix since it is more efficient (no need for a temporary). It
is likely that the compiler could optimize this away, but lets make
it efficient from the start.
I'm adding more uses of the make_range_from_width function, so
it seems like time to get rid of its use of the svector template.
This thread led to a lot of other uses of svector that had to
also be removed.
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.
The error routines for task and function definitions were incorrectly
popping the scope. This should not be done since no scope was pushed.
Also assert that the current_task/function is 0 to catch that kind of
error like the other definition rules.
Generate schemes may nest freely, but generate regions
(an anachronistic concept from 1364-2001) cannot nest,
not within schemes or other regions. Have the parser detect
the nesting and print an error message.
This is part of the 1800-2009 standard (Section 23.3.2.3) and allows
ports of module instances to be declared like:
modname instance(.foo, .bar);
instead of
modname instead(.foo(foo), .bar(bar));
The only tricky part about this is the implicit port connection shall
not create an implicit net declaration. To make this happen, the path
of least resistance was to add a bool to PEIdent indicating that it
should not implicitely create a net.
This does not rely on the generation flag to be 2009, following the
trend that new port naming convention (like ANSI style ports) work
regardless of the generation.
Added generation flag -g2009 which enables support for 1800-2009
constructs. Added related support such as "1800-2009" in the
`begin_keywords directive.
Keeps 2005 as the default generation for now.
Removed the -gsytem-verilog flag and folded the 1800-2005 stuff into
1800-2009. The rationale behind this is we have so little of
1800-2005 actually implemented that it does not make sense to
distinguish between 1800-2005 and 1800-2009 SystemVerilog extensions,
so we just count them all as the new 1800-2009 Verilog language.
Like I did for SystemVerilog the other day this patch adds all the
Verilog-AMS 2.3.1 keywords. This necessitated adding one my byte
to the gperf -k argument (byte 9) to make the laplace_?? tokens
have a unique hash.
This patch adds the SystemVerilog keywords to Icarus. This allows
use to easily verify that out plain Verilog does not contain any
SystemVerilog keywords. The keywords are not parsed in any way.
When parsing a Verilog file using -gsystem-verilog any identifier
that is a keyword will cause a parse error. It is the users
responsibility to figure out the problem since bison does not
give nice error message when it finds a keyword instead of an
identifier.
The $setuphold and $recrem timing checks can create delayed signals
that are needed to get a model to work correctly when negative timing
check values are used. Since we do not support timing checks and just
ignore them this can create simulation problems when a user tries to
use these delayed signals since they are not driven.
This patch adds a waring when the circuit is being compiled that these
delayed signals will not be driven. This will be needed until we get
time to add the real timing checks are mimic the delayed properties of
the timing check.
This patch modifies the original SystemVerilog timeunit/timeprecision
patch in the following way:
Removed trailing space.
Reworked some code to use standard spacing rules.
Added some comments.
Combined some code.
Major rework of local/global timeunit/timeprecision logic.
Major rework of timeunit/timeprecision declaration/check code.
This was needed to remove the shift/reduce warnings.
Add a number of checks for invalid combinations.
This patch adds code to parse and ignore the following timing checks:
$nochange 1364-1995
$skew 1364-1995
$fullskew 1364-2001
$removal 1364-2001
$timeskew 1364-2001
The other checks were already supported. These have not been tested,
but they use the same basic terms as the other checks. We can fully
test these when we actually implement them.
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.
Icarus has recognized this directive, but it did not do anything
with the information. This patch adds the functionality for most
common cases. It adds this by changing the input net type from
wire/tri to tri1 or tri0 depending on the pull. The issue is that
if the input net is not a wire or tri this is not safe and should
really be done as an external pull gate connected to the input.
We will need to handle this is it ever comes up. For now a sorry
message is printed.
This patch adds real functionality for `celldefine and pushes this
property to the run time which can access this with vpiCellInstance.
This is technically only available for a module, but all scopes
have the property and only modules should return true when the
'endmodule' is between a `celldefine and `endcelldefine directive.
The standard allows an output declared as "output reg" to be
given an initialization assignment in the output declaration.
this patch adds that functionality. Specifically:
output reg out = 1'b0;
works as expected.
The standard does not allow this, but it appears that other
simulators do. This patch adds the functionality, but prints
a warning message for the invalid task definition.
Allows iverilog to parse attribute like syntax that a common
simuator puts into automatically generated verilog code. This
syntax cannot be found in any of the IEEE standards.
The STRING lexical token was malloc based, but then was passed
to routines that are expecting a new based result. This patch
standardizes on a new/delete based approach.
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.
Verilog generate schemes support a special case where conditional
generate schemes that contain only a nested conditional generate
scheme do not create a new scope. Instead, it relies on the nested
generate scheme to generate the scope.
The goal is to completely remove the svector class because the standard
vector class works perfectly well. This removes the uses in the Module.h
header file.
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.
Support arrays of realtime variable arrays and net arrays. This
involved a simple fix to the ivl core parser, proper support in
the code generator, and rework the runtime support in vvp.
The arguments of logical and/or are self determined, and the width is
fixed as 1 bit. Account for this special behavior by creating the
PEBLogic class.
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.
This patch removes all the checks for constant expressions performed
during the parsing phase, as these checks are (mostly) repeated during
elaboration. It adds the missing check in the elaboration phase (the
RHS of a register initialisation), and improves the error reporting
and error recovery in other checks.
This patch fixes pr2132552, which was caused by a fault in the parser
constant expression checking.
Currently, parameters and localparams declared in tasks, functions,
generate blocks, and named blocks are placed in the parent module
scope. Event declarations in these scopes are not permitted (a
syntax error is reported). This patch corrects this behaviour, so
that all the above declarations are accepted and are placed in the
scope in which they are declared.
Note that the IEEE standard does not permit parameter declarations
in generate blocks. This patch causes the parser to reject such
declarations.
Nothing to do with tab width! Eliminates useless
trailing spaces and tabs, and nearly all <space><tab>
pairings. No change to derived files (e.g., .vvp),
non-master files (e.g., lxt2_write.c) or the new tgt-vhdl
directory.
Low priority, simple entropy reduction. Please apply
unless it deletes some steganographic content you want
to keep.
Statements can have attributes attached to them. Handle a few cases in
the parser where attributes may be attached to statements, and get them
as far as the pform.
This patch adds blocking repeat event controls and also makes the
base repeat statement sign aware. If the argument to repeat is
negative (it must be a signed variable) then this is treated just
like an argument of 0 (there is no looping). Doing this allows us
to model the repeat event control as follows.
lhs = repeat(count) @(event) rhs;
is translated to:
begin
temp = rhs;
repeat (count) @(event);
lhs = temp;
end
This patch also pushes the non-blocking event control
information to the elaboration phase where it will report they
are not currently supported.
This patch pushes the automatic property for both tasks and
functions to the code generators. The vvp back end does not
currently support this so it will error out during code
generation. The VHDL back end should be able to use this
property and tgt-stub prints the property. Having this will
also make it easier when we do adding this to the runtime.
This patch adds the time and realtime properties for user
task and function arguments. It also make a common rule
for real and realtime since they are the same.
This patch fixes a bug where a local parameter with only a range
was incorrectly setting the default parameter type to IVL_VT_NO_TYPE.
This would create a compile time assert for any untyped
parameter/localparam immediately following it.
Contribution statements have an l-value and r-value. Parse those
expressions into pform so that elaboration has something to work with.
In this process, this patch also changes the PECallFunction class to
use the vector template instead of the svector template. The latter
doesn't add anything over the STL vector template, so this is a start
of working the svector out.
Verilog-2001 only allows a single generate item within a generate-
endgenerate region, but allowed one to collect generate schemes with
begin/end blocks. Verilog-2005 cleaned up that mess, and it is the
2005 syntax that Icarus Verilog implements. This patch detects the
anachronistic use of begin/end within the generate region, ignores
the begin/end words, and prints a warning that the user is using an
obsolete syntax.
This patch adds the time and realtime types to parameters
and local parameters. It also makes the width (range) of
an integer parameter match the variable "integer_width"
(normally 32 bits). It also converts a real value to
an integer when a range is implicitly or explicitly
given. This all matches what the standard specifies.
Fixed an error in converting -1 to a unsized verinum.
Parameter value ranges support the exclude of a point as well as
range, so add the syntax to support that case. Internally it is
handled as a degenerate range, but the parse and initial elaboration
need to know about it.
Before this, the types of parameters were always logic, only the
width and signed-ness could be controlled. A parameter may take
on implicit real values if the expression were real.
With this patch, the type for the parameter can be explicitly set
to logic or real. This also means that the parameter real valued
expressions need to be more crefully treated, possibly with casting
integral expressions to real values, or real expressions to integral
values.
Handle parameter value ranges as far as the pform. The +-inf expressions
are not handled yet, nor is the single value exclude, but the other
cases are handled.
The VAMS-2.2 LRM syntax does not include a semicolon after the nature/
discipline name, but the 2.3 LRM does. Effectively, that means that
the simicolon is option from now on.
Pform parse enough of the natures that they can be mapped and the
disciplines can bind to them. Since Verilog-AMS expects natures to
be declared before use, we can do the binding early.
The VAMS-2.3 specification says that discipline and nature declarations
have a semi-colon after the identifier, but the disciplines.vams in
the appendix does not. Initial guess what that the disciplines.vams
is correct, but I've been told that the syntax is correct and the
disciplines.vams file is not.
Parse discipline declarations, net discipline declarations, and
analog contribution statements. Don't yet do anything useful with
these, just give a sorry message where they are encountered.
This is part of the standard disciplines header file, with enough
syntax to part the natures and disciplines included. Don't do anything
with the parse results yet.
This patch adds file and line information for parameters and
local parameters. It also adds file/line stubs for signals in
the tgt-* files. It adds the pform code needed to eventually
do genvar checks and passing of genvar file/line information.
It verifies that a genvar does not have the same name as a
parameter/local parameter.
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.
Verilog-2005 defines the base-10 log function to be $log10. This makes
sense because in C the log() function is the natural log. So add the
$log10 function.
Since there may be legacy code that uses the $log function, leave it
defined, but we should consider at least printing a warning when the
$log function is used.
Verilog-AMS recommends that users use the system-function style
math functions, but supports traditional style math functions for
portability. Add the keywords and parse the traditional Verilog-A
functions, and handle them as calls to the equivilent system
function.
Stephen Williams
Martin Whitaker
Cary R
Arun Persaud
Martin Whitaker
Larry Doolittle
Jared Casper
Prasad Joshi
Prasad Joshi
Sreeraj R