class
#include <slang/ast/EvalContext.h>
EvalContext A container for all context required to evaluate a statement or expression. Mostly this involves tracking the callstack and maintaining storage for local variables.
Public types
- struct Frame
- Represents a single frame in the call stack.
Public functions
- void reset()
- Resets the evaluation context back to an initial constructed state.
- auto createLocal(const ValueSymbol* symbol, ConstantValue value = nullptr) -> ConstantValue*
- Creates storage for a local variable in the current frame.
- auto findLocal(const ValueSymbol* symbol) -> ConstantValue*
- void deleteLocal(const ValueSymbol* symbol)
- auto pushFrame(const SubroutineSymbol& subroutine, SourceLocation callLocation, LookupLocation lookupLocation) -> bool
- Push a new frame onto the call stack.
- void pushEmptyFrame()
- void popFrame()
- Pop the active frame from the call stack.
- void pushLValue(LValue& lval)
- void popLValue()
- Pops the top of the lvalue stack (requires that the stack be non-empty).
- auto getTopLValue() const -> LValue*
- Gets the top of the lvalue stack, or nullptr if the stack is empty.
- auto step(SourceLocation loc) -> bool
- auto inFunction() const -> bool
- auto cacheResults() const -> bool
- auto disableCaching() -> auto
- auto topFrame() const -> const Frame&
- Gets the top of the call stack.
- auto getDisableTarget() const -> const Symbol*
- auto getDisableRange() const -> SourceRange
- void setDisableTarget(const Symbol* symbol, SourceRange range)
- void setQueueTarget(const ConstantValue* cv)
- auto getQueueTarget() const -> const ConstantValue*
- auto dumpStack() const -> std::string
- Dumps the contents of the call stack to a string for debugging.
- auto getDiagnostics() const -> const Diagnostics&
- Gets the set of diagnostics that have been produced during constant evaluation.
- auto addDiag(DiagCode code, SourceLocation location) -> Diagnostic&
- Records a diagnostic under the current evaluation context.
- void reportDiags(const ASTContext& context)
- Issues all recorded diagnostics to the given AST context.
- void reportStack(Diagnostic& diag) const
- Reports the current function call stack as notes to the given diagnostic.
Function documentation
ConstantValue* slang:: ast:: EvalContext:: findLocal(const ValueSymbol* symbol)
Gets the current value for the given local variable symbol. Returns nullptr if the symbol cannot be found.
void slang:: ast:: EvalContext:: deleteLocal(const ValueSymbol* symbol)
Removes a previously created local. Pointers to the local's storage will be invalidated.
void slang:: ast:: EvalContext:: pushEmptyFrame()
Pushes an empty frame onto the call stack. Intended for use with on-the-fly evaluation in a scripting context.
void slang:: ast:: EvalContext:: pushLValue(LValue& lval)
Pushes an lvalue onto the stack for later reference during evaluation. NOTE: the lvalue storage must remain alive for as long as it remains on the eval context's lvalue stack.
bool slang:: ast:: EvalContext:: step(SourceLocation loc)
Records the fact that we are executing another statement. This is used to count the number of statements executed so far to detect if we've been evaluating a single constant function for too long.
bool slang:: ast:: EvalContext:: inFunction() const
Returns true if the context is currently within a function call, and false if this is a top-level expression.
bool slang:: ast:: EvalContext:: cacheResults() const
Indicates whether the results of evaluating expressions using this context can be cached in each expression's constant
pointer.
auto slang:: ast:: EvalContext:: disableCaching()
If result caching is enabled, this method disables it and returns an object that when destructed will restore the previous caching mode. Otherwise does nothing.
const Symbol* slang:: ast:: EvalContext:: getDisableTarget() const
If a disable statement has been evaluated, this returns a pointer to the block that should be disabled (presumed to be higher up in the stack). Otherwise returns nullptr.
SourceRange slang:: ast:: EvalContext:: getDisableRange() const
If a disable statement has been evaluated, this returns the source range denoting where that statement occurred. Otherwise returns an empty range.
void slang:: ast:: EvalContext:: setDisableTarget(const Symbol* symbol,
SourceRange range)
Sets the target block that should be disabled, based on evaluating a disable statement. This can be set to nullptr to clear out the target once it has been found the disable is completed.
void slang:: ast:: EvalContext:: setQueueTarget(const ConstantValue* cv)
Sets the target queue value for use with unbounded '$' expressions. If set to nullptr, the target is cleared.
const ConstantValue* slang:: ast:: EvalContext:: getQueueTarget() const
Gets the target queue value for use with unbounded '$' expressions. Returns nullptr if there is no queue target active.