Add integral sum() and product() reductions, including expression
forms, for queues, dynamic arrays, and class properties.
Split from steveicarus/iverilog#1330 (part 05/6).
Extend locator methods to class queue and dynamic-array properties,
including min/max, unique/min/max with-predicates, and VVP array-pattern
object handling. Built on the #1419 locator helpers.
Split from steveicarus/iverilog#1330 (part 04/6).
Add find*, unique*, min/max, and with-predicate locator methods for
queues and dynamic arrays, with VVP runtime support and ivtest.
Split from steveicarus/iverilog#1330 (part 03/6).
Fold in Windows VPI routing for vpip_format_pretty, fix queue method
argument elaboration via elaborate_rval_expr, reject class tasks used as
expressions cleanly, and update br1005 now that class queues compile.
Review follow-up: move vpip_format_pretty to vpip_format.cc with
diagnostic return strings, restore NetNet-based queue method elaboration
with a separate property path, drop spurious /devel/ from .gitignore,
and bump copyright years on touched files.
Formatting pass per inline review: brace style for multi-line if bodies,
||/&& at end-of-line continuations, switch/case indentation, single-line
if returns, NetNet-based sys_task_method_ again, and aligned extern decls.
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>
The vvp reduction operators evaluate their input bit by bit. This is
expensive for wide vectors.
Add word wide reduction helpers to `vvp_vector4_t` and use them for both
reduction functors and vthread reduction opcodes.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The vthread binary logic opcodes update vectors bit by bit.
Use the in-place `vvp_vector4_t` operators instead. This reuses the word
wide implementation and avoids per-bit `value()` and `set_bit()` calls.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Partial out-of-bounds write to a function's return value will trigger an
assert, even though the operation is valid.
The assert checks that the truncated value has the expected width, but
instead it should check that the non-truncated value has the expected with.
Move the assert before the truncation to fix this.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
In the current implementation a `%fork` instruction in a final block will
get scheduled, but never executed.
And while SystemVerilog requires a `final` procedure to execute in 0 time
and so no SystemVerilog `fork` is allowed inside of it, there are some
other scenarios where iverilog generates `%fork` statements.
For example when declaring variables in a sub-block a sub-scope with its
own thread is is used to allocate the storage for those variables and
`%fork` is used to execute the child thread.
E.g. the following, while being valid SystemVerilog, will never execute the
loop because the generated code will implement the loop as a child thread
being executed by a `%fork` statement.
```
final for (int i = 0; i < 10; i++) $display(i);
```
To mitigate this treat final statements the same as functions and rather
than scheduling a child thread, execute it immediately when using the
`%fork` statement.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%pushi/str` and `%concati/str` instructions should remove null-bytes
from the string literal when converting it to a string. This is defined in
section 6.16 ("String data type") of the LRM (1800-2017).
This is already handled correctly when converting a vector from the stack
to a SV string, just not when converting a string literal to SV string.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
An empty dynamic array or queue is represented by a null object in vvp.
Currently when trying to copy such an object results in undefined behavior
in various places. Either hitting an assert or causing a nullptr
dereference.
Make sure that the empty object is handled correctly by treating it as a
special case.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%store/vec4a` instruction does not handle partial of full
out-of-bounds writes to a vector array element. Trying to do so will
trigger an assert. E.g.
```
integer a[3:0];
integer i = -10;
a[0][i+:8] = 8'h0; // Triggers assert
```
For fully out-of-bounds writes the write should be skipped, for partial
out-of-bounds writes the value needs to be resized to be within the bounds
of the vector. Use the `resize_rval_vec()` helper function to implement
this.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
There are a few functions that handle implement different kinds of vector
writes that have to handle that the assigned value partially or completely
out-of-bounds.
Each function has similar, but not identical, code for this, sometimes with
small bugs for corner cases.
Add a helper function that takes care of handling of updating the width and
offset of the assigned value if necessary.
This ensure consistent and correct behavior and allow to remove some
duplicated code.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%assign/vec4/a/{d,e}` instructions, when checking for a full
out-of-bounds write on the low side, uses the target signal width, while it
should use the assigned value width.
This can lead to a fully out-of-bounds write to be assumed to be a partial
out-of-bounds access, which will trigger an assert later on.
E.g.
```
integer a[1:0];
integer i = -4;
a[0][i+:4] <= 4'h0; // Triggers assert
```
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
A non-blocking event controlled assignment consists of 3 steps.
* Setup event
* Perform assignment
* Clear event
This works fine if the lvalue is a singular value. If the lvalue is a
concatenation multiple assignments are generated and the event is cleared
after each assignment. As a result only the first assignment is event
controlled. All other assignments will be regular non-blocking assignments.
E.g.
```
reg x, y;
event e;
{x,y} <= @e 2'b11;
$display(x, y); // x will be 1'b1, y will be 1'bx
```
To resolve this the event needs to be cleared after all assignments have
been done. This requires changes to both tgt-vvp and the vvp runtime.
tgt-vvp is updated to only insert a single `%evctl/c` instruction for each
event controlled non-blocking assignment.
The vvp runtime is not updated to implicitly clear the event in the
`%assign/vec4/e` instruction and instead rely on the explicit `%evctl/c`.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Both the `%concati/vec4` and `%pushi/vec4` instructions need to construct a
vector from the immediate value encoded in the instruction. Currently both
these instructions have a custom implementation for that.
Remove the custom implementations from those functions and use the
`get_immediate_rval()` helper function. This removes a bit of duplicated
code.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%cmp/ws` and `%cmp/wu` instructions compare two index registers. They
are currently unused. Since the index registers are not used for data there
is not really a need to compare them. Values can be compared before loading
them into an index register.
So remove these two instructions.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%mov/wu` instruction moves data from one index register to another.
The instruction is not used. It also does the same as `%ix/mov`. So remove
it.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `recv_vec{4,8}_pv()` functions are used to implement a partial write to
a vector. As parameters they take both the value and the width of the
value.
All callers of of these functions pass `val.size()` or a variation thereof
as the width of the value. And all implementations that do anything with
the data have an assert that `val.size() == wid`.
Remove the `wid` parameter from these functions and just use `val.size()`
directly where needed. This allows to simplify the interface and also
to remove the asserts.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The `%disable` instruction will stop the execution of all active
threads of a specific scope. This is what is required to implement
the semantics of the Verilog `disable` statement.
But it is not suited to implement the SystemVerilog flow control
statements such as `return`, `continue` and `break`. These only
affect the thread hierarchy from which it is called, but not other
concurrently running threads from the same scope.
Add a new `%disable/flow` instruction that will only disable the thread
closest to the current thread in the thread hierarchy. This can either be
the thread itself or one of its parents. This will leave other concurrent
threads of the same scope untouched and also allows function recursion
since only the closest parent thread is disabled.
Note that it is not possible to implement this using `%jmp` instructions
since a block in a function with variable declarations will be its own
sub-thread, but using flow control instructions it is possible to exit from
that thread to the parent scope, which is not possible with `%jmp`
instructions.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
String literals may have escaped special characters in them. Make sure
we are processing all the special characters that the standard supports,
and also fix the handling of the assignment to strings. Note that the
vvp input has string literals sanitized so that the parser can handle
the various binary values. desanitize the strings when pushing string
literals into the string stack. This fixes string assignments, and other
string operations.
IEEE Std 1800-2017 Section 7.6 Array assignments
Assignment of a dynamic array creates a duplicate of the source,
so that assignments to the copy don't impact the original. Handle
all sorts of dynamic array base types.
Since commit 15cda5fe, forked threads are never embedded in the parent
thread, so we no longer need the special case code that ensured that
task/function calls were reaped before a join.
This also fixes GitHub issue #368.
When -pfileline=1 is used the queue procedural warnings have file
and line information added to the messages. Also switch the trace
debugging to be off by default.
Also, Add some preliminary missing darray functionality.
mjoekhan
Cary R.
Lars-Peter Clausen
Stephen Williams
Martin Whitaker