Assignment patterns contain child expressions, but currently inherit
`PExpr::has_aa_term()` which always returns false. This means automatic
variables inside a pattern are not caught by checks for procedural `force`
and procedural continuous assignment statements.
Implement `has_aa_term()` for `PEAssignPattern` and recurse into all pattern
elements.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that a blocking intra-assignment delay on a real value preserves the
assigned value after the delay.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The vvp parser did not accept the local flag on `.var/real`
declarations. This can happen when elaboration creates a compiler-generated
real temporary, for example when a blocking intra-assignment delay is
rewritten from:
r = #1 1.25;
to assign the right hand side to a temporary before the delay and assign
the temporary to the target after the delay.
Add support for the local flag. Keep a VPI symbol for the variable so
`%load/real` can still resolve the label, but do not attach local real
variables to the current scope.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that visible type identifiers can be shadowed by declarations in
other namespaces or nested scopes. Keep each grammar category in a
separate regression so failures identify the affected rule.
Also check that package import and export items can name a type
identifier.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
SystemVerilog allows an identifier that is visible as a typedef to be
shadowed by a declaration in a nested scope or reused as a declaration
name in another namespace. The lexer can return `TYPE_IDENTIFIER` before
the new name has been installed, so these grammar positions reject
otherwise valid code.
This is not a complete conversion of all identifier grammar sites. Only
handle the trivial conflict-free cases where `IDENTIFIER` can be replaced
by `identifier_name` without any surrounding grammar changes.
Also stop type lookup when the current scope already has a local symbol
with the same name. This makes later references to a shadowing
declaration use the local symbol instead of an outer typedef.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The string substr() method reports an error if it is called with the wrong
number of arguments, but the error was not counted and elaboration continued
with missing function arguments. A call such as `s.substr(0)` could therefore
crash after printing the diagnostic.
Count the arity error and fill missing internal arguments with dummy constants
so elaboration can recover without building an incomplete system function call.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that unary real minus preserves the sign or bit pattern for zero,
NaN, and infinity. Each test starts with the positive value, negates it,
and then negates the result back to the positive value.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently the vvp target emits unary real minus as `0.0 - value`.
This is not the same operation for all real values. It loses the
negative zero result for `-(+0.0)` and does not reliably flip the sign
bit for NaN values whose bits are visible through `$realtobits`.
Add `%neg/wr` and use it for unary real minus. This performs a direct
negation of the real stack value, so zero, NaN and infinity all use the
same operation as unary minus instead of a binary subtraction from zero.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that the vvp code generator emits a -0.0 real constant with its
sign bit set, so the compiled value matches the runtime real value. The
sign used to be detected with (value < 0), which is false for IEEE 754
-0.0, and a -0.0 constant was turned into +0.0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Check that bogus member access on a procedural l-value is rejected with a
normal compile error instead of aborting during elaboration.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that an invalid indexed part select base on a procedural l-value is
reported as a normal compile error instead of crashing after the bind error.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently the procedural l-value path asserts if symbol lookup leaves a
member tail for a variable that is not a struct or class. For example,
`r.bad = 1'b1;` where `r` is a scalar variable aborts during elaboration
instead of reporting a normal error.
Report an error for the leftover member path before the assertion. This
matches the r-value path behavior for the same kind of invalid member access.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The l-value indexed part select path elaborates the base expression with
`elab_and_eval()`. If the base expression can not be bound this returns a
nullptr, but the l-value path dereferenced it while checking the expression
type. For example, `a[does_not_exist -: 2] = 2'b00;` reported the bind error
and then crashed.
Return early when base elaboration fails. This matches the r-value indexed
part select path and leaves the existing bind error as the reported
elaboration error.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently vvp_reg.py uses `returncode >= 256` to distinguish execution
errors from ordinary compile or simulation failures. That matches the encoded
status returned by wait(), but subprocess.run() does not expose that value. Its
returncode is the decoded process exit status, or `-N` if the process was
terminated by signal N. Shell wrappers can also report signal termination as
`128 + N`.
As a result a compiler crash can be reported as `-11` or `139`. Both values
pass the old check and a CE test can be accepted as a normal compiler error.
Treat negative return codes and return codes greater than or equal to 128 as
execution errors before accepting CE and EF results. Also make sure that CE gold
mismatches are reported as failures.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The vlog95 backend currently emits `$unsigned()` when it needs to create a
self-determined unsigned expression context. `$unsigned()` is part of the
optional signed expression support in this backend and is only available when
the signed support flag is enabled.
Concatenation is part of the baseline Verilog-95 output and also creates a
self-determined unsigned expression context. Use `{expr}` for the unsigned case
and keep using `$signed()` when a signed context is needed.
Remove `-pallowsigned=1` from the existing vlog95 regression tests that now
pass without the optional signed support flag.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that synthesized case statement muxes can use array words as inputs.
This used to generate invalid VVP because .array/port statements were emitted
in the middle of .functor statements.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently draw_lpm_mux_nest() calls draw_net_input() while printing a
.functor statement. For array word inputs draw_net_input() emits an
.array/port statement as a side effect, which interleaves the .array/port
text into the middle of the .functor line and generates invalid VVP.
draw_lpm_substitute() has the same pattern. Collect the input labels before
starting to print the consuming statement so any side-effect output appears
as a separate statement first.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that a class declared in a conditional generate block can be used.
Also check that classes declared in a generate loop get separate class scopes
for each generated instance.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
SystemVerilog allows class declarations as module and generate items.
Currently a class declaration in a generate block triggers an assert because
`pform_push_class_scope()` only records classes in `PScopeExtra` scopes.
Add class storage to `PGenerate` and elaborate those classes like module and
package classes. When registering task, function or class declarations, only
use the current `PGenerate` object as the target if it is also the current
lexical scope. This distinction matters for generated classes because
`pform_cur_generate` remains set while the class body is parsed, but the
current lexical scope has changed to the `PClass`. This records the class
declaration in the generate block while leaving methods and constructors in
the class scope.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that using a class task through an object method call in expression
context reports a compile/elaboration error instead of triggering an assert.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Class object method calls in expression context call func_def() without first
checking that the resolved class method is a function. If the method is a task,
func_def() triggers an assert instead of reporting a normal elaboration error.
Check the method scope type before accessing the function definition and report
an error for tasks.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently NetAssignNB::dump() prints a malformed fallback marker when
there is no rval expression. The leading '<' is missing, making it
inconsistent with the blocking assignment dump output.
Print the complete error marker.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The methods for handling up and down part select are nearly identical
and only differ in a hand full of lines.
Consolidate them into a single method to remove the duplicated code.
This makes it easier to maintain the code and add future changes.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The methods for handling up and down part select are nearly identical
and only differ in a hand full of lines.
Consolidate them into a single method to remove the duplicated code.
This makes it easier to maintain the code and add future changes.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that enum literals declared by enum typedefs in generate blocks, named
blocks, tasks and functions can be referenced from the same scope.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Enum types declared inside nested scopes are stored separately from typedefs.
The enum sets need to be elaborated when the `NetScope` is created so enum
literals are available for declarations and statements in the same scope.
Module, package and class scopes already do this. Generate, task, function and
named block scopes can also declare enum typedefs, but did not elaborate their
enum sets. Elaborate them while setting up these scopes.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The VPI label resolver parses word and string labels into a 32 byte
temporary buffer. The scansets used by sscanf() did not specify a width,
so malformed labels could write past the end of the buffer.
Limit the scansets to the size of the buffer.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that an empty old-style UDP table reports the parser error and the
invalid primitive error instead of crashing.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
An empty old-style UDP table leaves the parsed table pointer unset after
the parser reports the table error. The old-style UDP creation path still
passed the null pointer to process_udp_table(), which crashes.
Report an invalid UDP table instead and do not register the primitive.
Also keep the new-style invalid-table diagnostic formatting consistent.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that variable selects of a packed array with negative bounds use the
correct index width and can read back assigned elements.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Variable select base normalization extends the base expression to cover
the packed array bounds. The current code compared min_wid against
num_bits() of each bound, but then assigned the bound value itself to
min_wid.
For positive bounds this can make the generated index expression much
wider than required. For negative bounds the effect is much worse since
min_wid is unsigned. Assigning a negative bound converts it to a huge
width, causing elaboration to try to pad the expression to that size and
abort or run out of memory for otherwise valid variable selects.
Use the bit width of the bound instead of the bound value.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that statements that are not allowed in functions or final procedures
are still rejected when they are placed in a named block scope.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Currently checks for statements that are not allowed in functions or final
procedures only inspect the immediate scope. If the statement is inside a
named block or a block with declarations, the current scope is the block and
the context is lost.
Make `NetScope::in_func()` and `NetScope::in_final()` preserve the context
through begin-end, fork-join and generate block scopes. Other scope types are
treated as context boundaries so function and final state does not leak across
subroutine or definition scopes.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Check that queue push_back(), push_front() and insert() report errors when
called with too few or too many arguments.
These tests are expected to fail as compile/elaboration errors. They also make
sure the invalid calls do not crash during elaboration while reporting the
argument count error.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>