A relational break signal generating device including two relational comparators which independently compare an address input from a microprocessor to reference addresses previously input thereto and generate output signals which are fed into a combinational logic circuit that produces false and break signals when a prespecified relationship between the input program address and the two reference addresses occurs. The device also includes a circuit for generating pulses each time a break point is detected.
A software debugging analyzer nonintrusively acquires data concerning the execution of software on a real-time basis. Low-level event recognition is accomplished with programmable comparators, whose outputs are fed to high-level recognition comparators to define complex events. Dynamic recognition is provided by recognition cmparators programmable on a real time basis as variables are actuated. Acquired data is stored in memory in either a sequential or random access mode. A microprocessor translates high level commands into event constructs and processes the acquired data into a format suitable for display to a user.
Disclosed is a method and an apparatus for range checking a value in a programmable system. An instruction prefix LDRNG enables the checking of a value against one or both limits of a range of values. The value is calculated as part of the execution of a primary instruction which is any suitable instruction, such as ADD, MOVE, STORE, etc., that directly follows the prefix. During the execution of the primary instruction the range check is performed, and an exception is taken without completing execution of the primary instruction if the value does not lie within the range.
A circuit by which an SWI instruction held in a memory circuit is switchedly input in response to a signal supplied externally is provided in a processor, whereby the substitution of a program word can be realized using such an internal circuit, so that a high-speed and reliable break in program execution can be effected. Moreover, an interrupt function separate from normal interrupts is established by setting a specified operation mode, whereby, when a data processor is used as an emulator, the break of a user program including the ordinary interrupt processes can be easily effected by utilizing the special interrupt function. Also, by additionally providing the function of delivering out a signal indicative of the break status, an external circuit can be simplified.
A software performance analyzer nonintrusively measures six different aspects of software execution. These include histograms or a table indicating the degree of memory activity within a collection of specified address ranges, or indicating the amount of memory of bus activity caused by the execution of programming fetched from within a collection of specified ranges, or indicating for a specified program the relative frequency with which it actually executes in specified lengths of time, or indicating for a specified program the relative frequency of a collection of specified available potential execution times (i.e., the complement of the previous measurement), or indicating for two specified programs the relative frequency of a specified collection time intervals between the end of one of the programs and the start of the other, or lastly, indicating the number of transitions between selected pairs of programs. All measurements may be either percentages relative to only the specified programs or ranges, or may be absolute percentages with respect to all activity occurring during the measurement. Acquired data may be in terms of time or of qualified occurrences of a specified event. Enable/disable and windowing for context recognition are available. The measurements are made by rendomly choosing and monitoring a first range for a selected period of time. An address range detector and bus status recognizer supply information to a state machine configured to control the particular type of measurement desired. Various counters are responsive to the state machine and accumulate data later reduced by software controlling the software performance analyzer. At the end of the monitoring period the next address range is monitored, and so on until the entire list has been used, whereupon a new random starting range is chosen and the measurement continues. The first two types of measurements listed above may also be performed in a real-time mode where two ranges are in fact monitored simultaneously and nearly continuously.
A breakpoint unit contains a memory circuit which monitors digital signals for the occurrence of any of a plurality of predetermined conditions. The memory circuit includes an array of memory cells (each cell storing data determining a value of a breakpoint condition of interest), and selected ones of the cells can be read in response to various combinations of the signal bits. In some embodiments, the array includes 2.sup.N cells and data stored in each cell is readable in response to N binary signal bits which are treated as an N-bit address signal. The memory circuit outputs the accessed data value from one memory cell, which would be used as a breakpoint signal that halts or initiates operation of the circuit originating the signals being monitored.
