The "->" operator is rarely used, but exists. Unfortunately, the syntax
is tied up in a horrible mess with the System Verilog constraint list
syntax. Do some flex magic to make it all work.
Explicit imports should always conflict with local declarations using
the same name. Wildcard imports only conflict if they are referenced
before a local declaration with the same name.
This also unifies the detection of identifier conflicts.
This implements and enforces the full set of rules for determining
timescales in SystemVerilog. The previous relaxation of the rules
that allowed timescales to be redefined within the compilation unit
scope has been removed. Time unit and precision redeclarations are
now recognised after a nested module declaration.
This relies on using the automatically generated name for the unit scope.
This could collide with an escaped identifier, so it would be better to
identify the scope by a reference to the PPackage object, but for now,
do it the easy way.
This adds a -u option to the driver to allow the user to specify that
they want each source file to be treated as a separate compilation
unit, and modifies the compiler to accept a list of files (either on
the command line or via a file specified by a new -F option). This
list of files is then preprocessed and parsed separately, causing all
compiler directives (including macro definitions) to only apply to the
file containing them, as required by the SystemVerilog standard.
Replace explicit comparisons against generation_flag with calls to
the gn_system_verilog helper function, both for code clarity and
to fix a couple of bugs. Also simplify the implementation of the
function, as we already rely on the generation_flag enumeration
being an ordered list.
The bug report was for an assertion failure when a number contained only
a lowline (e.g. 'b_), but the standard says that a number can't start
with a lowline (e.g. 'b_1). The parser already rejected these cases for
decimal numbers, but allowed them through for binary/octal/hex numbers.
To be strictly compliant with the standard and compatible with other
EDA tools, unsized numbers should be treated as having a fixed size
(the same size as an integer). The -gstrict-expr-width option is
extended to allow the user to enable this behaviour.
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.
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 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 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.
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>
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>
Added an explicit option prefix="yy" to files that were generated
without an explicit -P.
This makes the lex-generated symbol names self contained without any
help from from build system.
Stephen Williams
Martin Whitaker
Cary R
Larry Doolittle
Arun Persaud
Martin Whitaker
Prasad Joshi
Greg Steuck
Jared Casper