slang::analysis namespace

Post-elaboration analysis framework.

Classes

class FlowAnalysisBase
A base class for flow analysis passes that contains non-specialized helper functions.
template<typename TDerived, typename TState>
class AbstractFlowAnalysis
An abstract class for flow analysis passes over SystemVerilog code.
class AnalyzedScope
Represents an analyzed AST scope.
class AnalysisContext
Holds various bits of state needed to perform analysis.
class AnalysisManager
The analysis manager coordinates running various analyses on AST symbols.
struct AnalysisOptions
Contains various options that can control analysis behavior.
class AnalyzedAssertion
Represents an analyzed assertion (or procedural checker).
struct ReadRange
A bit range read from a symbol within a procedure.
struct SensitivityList
Describes the effective sensitivity list for a SystemVerilog procedure.
class AnalyzedProcedure
Represents an analyzed procedure.
class CaseDecisionDag
A helper class for building a decision DAG (directed acyclic graph) for case statement exhaustiveness analysis.
class ClockInference
Various helper methods for inferring clocks in assertions and checkers.
template<typename TDerived, typename TState>
class DataFlowAnalysis
The base class for data flow analysis implementations.
struct DataFlowState
Represents the state of a data flow analysis at a single point in a procedure.
class DefaultDFA
The default concrete implementation of data flow analysis.
class DFAResults
Contains the results of running data flow analysis on a procedure.
struct InstanceDriverState
State tracked per canonical instance.
class DriverTracker
A helper class that tracks drivers for all symbols in a thread-safe manner.
class TautologicalCompare
Lint checks for comparisons (and logical combinations of comparisons) whose result can be determined without knowing the runtime values involved, which almost always indicates a bug.
class ValueDriver
Represents an expression that drives a value by assigning to some range of its type.

Enums

enum class AnalysisFlags { None = 0, CheckUnused = 1 << 0, FullCaseUniquePriority = 1 << 1, FullCaseFourState = 1 << 2, AllowMultiDrivenLocals = 1 << 3, AllowDupInitialDrivers = 1 << 4, CheckShadow = 1 << 5, InlineContAssignFunctionReads = 1 << 6, AlwaysStarUsesLSPs = 1 << 7, ContAssignUsesLSPs = 1 << 8, AllowMultiDrivenDynamicallySizedArrays = 1 << 9 }
Defines flags that control analysis behavior.
enum class DriverSource: uint8_t { Initial, Final, Always, AlwaysComb, AlwaysLatch, AlwaysFF, Subroutine, Other }
Specifies possible containing symbol kinds for value drivers.
enum class DriverFlags: uint8_t { None = 0, InputPort = 1 << 0, OutputPort = 1 << 1, ClockVar = 1 << 2, Initializer = 1 << 3, FromSideEffect = 1 << 4, HasOverrideRange = 1 << 5, ViaIndirectPort = 1 << 6 }
A set of flags that control how assignments are checked.

Enum documentation

enum class slang::analysis::AnalysisFlags
#include <slang/analysis/AnalysisOptions.h>

Defines flags that control analysis behavior.

Enumerators
None

No flags specified.
CheckUnused

Analysis should check for and report on unused symbols.
FullCaseUniquePriority

'unique' and 'priority' keywords are used to assume full case coverage.
FullCaseFourState

Require X and Z bits be covered for full case coverage.

If not set, only 0 and 1 bits are required.
AllowMultiDrivenLocals

Allow multi-driven subroutine local variables.
AllowDupInitialDrivers

Signals driven by an always_comb are normally not allowed to be driven by any other process.

This flag allows initial blocks to also drive such signals.
CheckShadow

Analysis should check for and report on declarations that shadow declarations in outer scopes.
InlineContAssignFunctionReads

When set, reads within functions called from a continuous assignment (assign statement) are inlined into the assignment's implicit sensitivity read-set, matching the behaviour of always_comb.

The LRM does not specify whether function bodies should be inlined for continuous assignments; different simulators choose differently. The default (flag not set) is to include only the signals directly visible in the assignment expression, consistent with always * behaviour.
AlwaysStarUsesLSPs

When set, always * uses longest static prefix (LSP) ranges when building its implicit sensitivity list, matching the behaviour of always_comb.

This is a non-standard extension supported by some simulators.

Per LRM 9.4.2.2 the default (flag not set) is to treat the sensitivity as covering the entire variable for any partial select – i.e. the sensitivity is derived from identifiers only, not from LSPs.
ContAssignUsesLSPs

When set, assign (continuous assignment) uses longest static prefix (LSP) ranges when building its implicit sensitivity list, matching the behaviour of always_comb.

The LRM does not specify exactly how continuous assignment sensitivities should be determined; different simulators choose differently. The default (flag not set) is to treat the sensitivity as covering the entire variable for any partial select – i.e. the sensitivity is derived from identifiers only, not from LSPs.
AllowMultiDrivenDynamicallySizedArrays

Signals driven by an always_comb or always_ff are normally not allowed to be driven by any other process.

The elements of dynamic arrays, associative arrays, and queues have no fixed bit range to tell them apart, so a write to any one of them counts as a write to the whole array. This flag lifts the restriction for such arrays.

enum class slang::analysis::DriverSource: uint8_t
#include <slang/analysis/ValueDriver.h>

Specifies possible containing symbol kinds for value drivers.

enum class slang::analysis::DriverFlags: uint8_t
#include <slang/analysis/ValueDriver.h>

A set of flags that control how assignments are checked.

Enumerators
None

No special assignment behavior specified.
InputPort

The assignment is for an input port of a module / interface / program (the assignment to the internal symbol from the port itself).
OutputPort

The assignment is for an output port of a module / interface / program (the assignment from the port connection).
ClockVar

The assignment is from a clocking block signal.
Initializer

The driver is for a net or variable initializer.
FromSideEffect

The driver is from a side effect of applying a cached instance body.
HasOverrideRange

The ValueDriver object has an override range stored with it.
ViaIndirectPort

The driver connects through an indirect port, such as a modport or ref port.