This saves about 5% memory. V3AstUserAllocator is appropriate for most use
cases, performance is marginally up as we are mostly D-cache bound on
large designs.
This makes the implementation of the detection and propagation of the
suspendable property simpler and easier to read. More importantly, there are no
more jumps around the AST with the `visit` functions, which in some cases could
result in incorrect visitor context while in the `visit` function. See the added
test, which would cause Verilator to segfault before this patch.
In testing, verilation performance was not shown to be affected by this change.
Though there is a slight performance improvement from this patch, due to adding
one more check before refreshing class member cache.
Signed-off-by: Krzysztof Bieganski <kbieganski@antmicro.com>
`VlNow{}` is completely unnecessary, as coroutines are always on the
heap (unless optimized out). Also fix access of var ref passed to forked processes.
Apart from the representational changes below, this patch renames
AstNodeMath to AstNodeExpr, and AstCMath to AstCExpr.
Now every expression (i.e.: those AstNodes that represent a [possibly
void] value, with value being interpreted in a very general sense) has
AstNodeExpr as a super class. This necessitates the introduction of an
AstStmtExpr, which represents an expression in statement position, e.g :
'foo();' would be represented as AstStmtExpr(AstCCall(foo)). In exchange
we can get rid of isStatement() in AstNodeStmt, which now really always
represent a statement
Peak memory consumption and verilation speed are not measurably changed.
Partial step towards #3420
In non-static contexts like class objects or stack frames, the use of
global trigger evaluation is not feasible. The concept of dynamic
triggers allows for trigger evaluation in such cases. These triggers are
simply local variables, and coroutines are themselves responsible for
evaluating them. They await the global dynamic trigger scheduler object,
which is responsible for resuming them during the trigger evaluation
step in the 'act' eval region. Once the trigger is set, they await the
dynamic trigger scheduler once again, and then get resumed during the
resumption step in the 'act' eval region.
Signed-off-by: Krzysztof Bieganski <kbieganski@antmicro.com>
Use the same style, and reuse the bulk of astgen to generate DfgVertex
related code. In particular allow for easier definition of custom
DfgVertex sub-types that do not directly correspond to an AstNode
sub-type. Also introduces specific names for the fixed arity vertices.
No functional change intended.