International Business Machines Corporation

Ali S El-Zein

Wolfgang Roesner

Viresh Paruthi

Gabor Drasny

Gabor Bobok

Fadi A Zaraket

Robert J Shadowen

Stephen Gerard Shuma

Alvan Wing Ng

Stephen J Barnfield

Derek E Williams

Jason Raymond Baumgartner

Benedikt Geukes

Klaus-Dieter Schubert

Chung-Lung K Shum

Luis Alfonso Lastras-Montano

Robert Lowell Kanzelman

Robert Alan Cargnoni

Michael H Wood

Barry Marshall Trager

Alexey Y Lvov

Shmuel Winograd

Mark A Williams

Clay Chip Smith

Birgit Schubert

Richard L H Carbone

Hussein Sharafeddin

Daniel Scott Heller

Gradus (Geert) Janssen

Edward Armayor McQuade

A first plurality of hardware description language (HDL) files describe a hierarchical integrated circuit design utilizing a simplified HDL syntax that omits specification of logical clock connections for at least some entities in the hierarchical integrated circuit design. The hierarchical integrated circuit design as described by the first plurality of HDL files is processed to automatically add logical clock connections for entities in the hierarchical integrated circuit design for which specification of logical clock connections are omitted in the first plurality of HDL files. Based on the processing, a second plurality of HDL files defining the hierarchical integrated circuit design is generated.

Logical clock connection in an integrated circuit design

Based on a directive in a control file, a processor pre-routes, within a hierarchical integrated circuit design, a signal through one or more levels of design hierarchy between a signal source at a higher level of the design hierarchy and an entity instance at a lower level of the design hierarchy. The processor processes entity instances in the design hierarchy in a bottom-up manner to insert technology-specific structures into the hierarchical integrated circuit design. During the processing, the processor inserts into a particular entity instance of the design hierarchy a technology-specific structure and connects the technology-specific structure to the signal pre-routed to the particular entity instance by the pre-routing.

Signal pre-routing in an integrated circuit design

A processor receives, as input, a first hardware description language (HDL) file defining an entity of a modular circuit design. The first HDL file instantiates, by a storage element declaration in a hardware description language, a storage element within the entity. The first HDL file omits a port map for the storage element. Based on the first HDL file, the processor automatically fully elaborates a port map for the storage element. The processor stores, in data storage, a derived second HDL file defining the entity and including the port map.

Clock mapping in an integrated circuit design

Method and apparatus for managing connections within a netlist include using a clone module to the connections between different components within the netlist. A buffer may be inserted between components of a netlist to split a connection into multiple segments and then moved into an associated first instance. The inclusion of the buffer allows for one or more of pin cloning and subway utilization to occur when mapping between a functional hierarchy to a physical hierarchy is performed.

Pin cloning and subway creation on automatically generated design physical hierarchy

Embodiments of the present invention provides methods, computer program products, and a system for processing hierarchical references for a formal equivalence check. In certain embodiments, hierarchical references of a first design are identified as functionally equivalent to hierarchical references of a second design. Value outputs of the first design can be compared to the value outputs of the second design to determine whether the value outputs of the respective designs match.

Equivalency verification for hierarchical references

A method of non-invasive insertion of logic functions into a register-transfer level (RTL) design, including: selecting a logic function to insert into a RTL design; identifying each hierarchical level executing at least a portion of the logic function; identifying a highest hierarchical level amongst hierarchical levels having each hierarchical level executing at least a portion of the logic function; and inserting all connections necessary to execute the logic function into a hardware description representation of the highest hierarchical level, without modifying a hardware description representation of any other hierarchical levels.

Non-invasive insertion of logic functions into a register-transfer level ('RTL') design

Preprocessing parallel sequences of 'wait' statements and synthesizing these multiple 'wait' statements to construct support for RTL tools. This is accomplished by preprocessing a VHDL process with multiple wait statements (referred to as BehFSM) into an equivalent register transfer.

Synthesizing VHDL multiple wait FSMS into RT level FSMS by preprocessing

In one exemplary embodiment of the invention, a method includes: receiving a first description for a circuit whose operation over a plurality of inputs is to be verified; receiving a second description for expected behavior of the circuit, where the expected behavior in the second description is expressed as a set of algebraic systems of multivariable polynomials over at least one Galois field; applying at least one computational algebraic geometry technique to a combination of the first description and the second description to determine whether the circuit is verified, where verification of the circuit confirms that at least one output obtained based on the first description corresponds to at least one expected value based on the expected behavior expressed in the second description; and outputting an indication as to whether the circuit is verified.

Circuit verification using computational algebraic geometry

Synthesizing VHDL multiple wait behavioral FSMs into RT level FSMs by preprocessing

A logic design and synthesis program, method and system provides intelligibility and independence of separate blocks in digital logic designs at the synthesis level. The sequential and combinational logic are separated and the sequential logic is then mapped to flip-flop library components. State-retaining elements, i.e., flip-flops detected in the input hardware description language (HDL) are represented in the sequential logic HDL output. The combinational logic HDL and the sequential logic HDL are connected only by signals, so signals are introduced to represent the flip-flop signals and variables detected in the input HDL. The sequential and combinational logic HDL are then synthesized to produce the design.

Abstraction level-preserving conversion of flip-flop-inferred hardware description language (HDL) to instantiated HDL

Co-Optimization utilizing Symbolic Execution (COSE) works across components of an embedded design to optimize structures therein. COSE utilizes symbolic execution (SE) to analyze software components and defines a limited set of values that software feeds hardware as constraints. SE explores substantially all possible paths of execution of the code specifying a component. It accomplishes this by accumulating path conditions (PCs) and annotating them to the corresponding segments of the component. A PC is associated with a branch of code and consists of the conjunction of conditions over input and state variables necessary and sufficient for the branch to execute. These PCs define constraints that limit the set of values that software feeds hardware. These constraints are then propagated across the networks of the design and employ static analysis techniques such as constant propagation, redundancy removal, and don't care optimizations to reduce the hardware components.

Co-optimization of embedded systems utilizing symbolic execution

Method, system, and program product for processing hardware design language code to facilitate reuse of compiled code units including options and option values in compiled code units. The method includes the steps of grouping options and option values to determine if code controlled by them will be reused; and determining options and option values that would permit and prevent reuse of compiled code units.

Compiler option consistency checking during incremental hardware design language compilation

A method of verifying a software system includes receiving a description of a software system described utilizing a high-level modeling language, and responsive thereto, parsing the description and constructing an abstract syntax graph. The abstract syntax graph is transformed into a sequential logic representation of the software system. The sequential logic representation is formed by reference to a Hardware Description Language (HDL) library. Then, the sequential logic representation is transformed into a gate-level sequential logic representation. Following the transforming, the software system is verified based upon the gate-level sequential logic representation. Following verification, results of verification of the software system are output.

Sequential encoding for relational analysis (SERA) of a software model

A method, system and computer program product for modeling variables in subprograms of a HDL program. A subprogram is provided with an initial value of a variable of an element being modeled and the subprogram is stored in memory of a data processing system. In response to a subprogram call, a copy of the stored subprogram is provided to the requesting HDL program. During execution, the initial value of the variable in the provided copy of the subprogram may be modified by the HDL program, but the value retains unchanged in the stored subprogram.

Techniques for modeling variables in subprograms of hardware description language programs

Unrolling the 'generate' statement of a hardware description language ('HDL') and displaying the unrolled HDL. For a conditional generate the condition is evaluated. If the statement is true the enclosed HDL code will be displayed. For an iterative generate, the enclosing HDL will be displayed as many times as specified by the bounds of the iteration scheme. This allows, for example, simulation value annotations for signals declared inside the generate statement, semantic navigation inside the generate statements, and allows the user to visualize what is included in the target design.

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Austin, TX, United States of America

Ali S El-Zein