Dynamic allocation of multidimensional array memory space

Claim 1

In a computer system having a digital processor and an addressable memory storing at least one first descriptor word having an address field pointing to an address location in the memory, a length field and a control field, apparatus comprising means responsive to a first condition of the control field of the first descriptor word for generating a second descriptor word having an address field, a length field and a control field, said descriptor generating means including means for modifying the contents of the address field of the said first descriptor word by a predetermined amount and loading the result in the address field of the second descriptor word, said descriptor generating means further including means for loading the contents of the location in memory addressed by the address field of the first descriptor word in the length field of the second descriptor word, and means for storing the generated second descriptor word in memory.

Claim 14

The method of allocating memory space in an addressable memory to a multidimensional array in a digital computer system during execution of an object program, comprising the steps of: initially storing as part of the program in memory a first descriptor word for the first dimension of the array and a table of words containing a word for each of the higher order dimensions of the array, the first descriptor word having an address field pointing to the first word in the table, a length field defining the size of the first dimension of the array, and a control field identifying various operational conditions, the words in the table each having a length field defining the size of a corresponding one of the higher order dimensions; sensing the contents of the first descriptor whenever an element in the array is needed during execution of the program, in response to a first sensed condition of the control field of the first descriptor; obtaining an available space in memory corresponding in length to the sensed condition of the length field of the first descriptor word; generating a second descriptor word having a length field corresponding to the length field of the word in said table pointed to by the sensed address field of the first descriptor word, having an address field corresponding to the address of the next word in the table, and having a control field indicating whether the word pointed to by the address field of the first descriptor is the last word in the table; storing the second descriptor word in each location of said space in memory; changing the address field of the first descriptor word to correspond to the address of the first location in said memory space; and changing the control field to indicate a second control condition.

Claim 15

The method of allocating memory space in an addressable memory to a multidimensional array in a digital computer system during execution of an object program, comprising the steps of: initially storing as part of the program in memory a first descriptor word for the first dimension of the array and a table of words containing a word for each of the higher order dimensions of the array, the first descriptor word having an address field pointing to the first word in the table, a length field defining the size of the first dimension of the array, and a control field identifying various operational conditions, the words in the table each having a length field defining the size of a corresponding one of the higher order dimensions; sensing the contents of the first descriptor whenever an element in the array is needed during execution of the program, in response to a first sensed condition of the control field of the first descriptor; obtaining an available space in memory corresponding in length to the sensed condition of the length field of the first descriptor word; generating a second descriptor word having a length field corresponding to the length field of the word in said table pointed to by the sensed address field of the first descriptor word, having an address field corresponding to the address of the next word in the table, and having a control field indicating whether the word pointed to by the address field of the first descriptor is the last word in the table; storing the second descriptor word in each location of said space in memory; changing the address field of the first descriptor word to correspond to the address of the first location in said memory space; and changing the control field to indicate a second control condition.

Claim 16

The method of allocating memory space to an array of data during execution of a program, the array having at least two dimensions, utilizing an initial descriptor word and a table of array information words stored in memory at the start of the program, the descriptor word having a length field indicating the size of the first dimension of the array, an address field indicating the address of the first word in the table, presence field indicating that the descriptor word does not point to an available space in memory, and a special field indicating that descriptors of an additional dimension to the array have not been allocated, each word in the table having a size field of one dimension of the array, and a last word field indicating whether or not the word containing the last word field is the final word in the table corresponding to the highest order dimension of the array, the method comprising the steps of: reading out the initial descriptor word from memory the first time data in the array is needed by the program, sensing the presence field of the descriptor word to determine if the descriptor word points to available space in memory, utilizing the length field of the descriptor word to locate and identify the base address of an available space in memory corresponding in size to the length field if the presence field indicates no space has been made available, sEnsing the special field in the descriptor word to determine if descriptors have been allocated to the first dimension, reading out the first word in the table from the location in memory identified by the address field of the initial descriptor if the special field indicates no descriptor has been allocated to the first dimension, generating a first dimension descriptor word having a length field corresponding to the size field in the word read out of the table, a presence field indicating that that descriptor word does not point to available space in memory, a special field corresponding to the last word field in the word read out of the table, and an address field corresponding to the address of the next word in the table if the last word field indicates that the word read out of the table is not the final word in the table, and storing the first dimension descriptor word in each of the locations in the memory space made available in response to the presence field of the initial descriptor word, starting with said base address.

Claim 17

The method of allocating memory space to an array of data during execution of a program, the array having at least two dimensions, utilizing an initial descriptor word and a table of array information words stored in memory at the start of the program, the descriptor word having a length field indicating the size of the first dimension of the array, an address field indicating the address of the first word in the table, presence field indicating that the descriptor word does not point to an available space in memory, and a special field indicating that descriptors of an additional dimension to the array have not been allocated, each word in the table having a size field of one dimension of the array, and a last word field indicating whether or not the word containing the last word field is the final word in the table corresponding to the highest order dimension of the array, the method comprising the steps of: reading out the initial descriptor word from memory the first time data in the array is needed by the program, sensing the presence field of the descriptor word to determine if the descriptor word points to available space in memory, utilizing the length field of the descriptor word to locate and identify the base address of an available space in memory corresponding in size to the length field if the presence field indicates no space has been made available, sEnsing the special field in the descriptor word to determine if descriptors have been allocated to the first dimension, reading out the first word in the table from the location in memory identified by the address field of the initial descriptor if the special field indicates no descriptor has been allocated to the first dimension, generating a first dimension descriptor word having a length field corresponding to the size field in the word read out of the table, a presence field indicating that that descriptor word does not point to available space in memory, a special field corresponding to the last word field in the word read out of the table, and an address field corresponding to the address of the next word in the table if the last word field indicates that the word read out of the table is not the final word in the table, and storing the first dimension descriptor word in each of the locations in the memory space made available in response to the presence field of the initial descriptor word, starting with said base address.

Claim 19

The method of allocating memory space in an addressable memory to a multidimensional array in a digital computer system during execution of an object program wherein, as part of the program, memory initially contains a first descriptor word for a first dimension of the array and a table of words containing a word for each of the other dimensions of the array, the first descriptor word pointing to the first word in the table and defining the size limit of the first dimension of the array, the words in the table defining the size limit of the other dimensions of the array, the method comprising the steps of: determining the size limit of the first dimension from the first descriptor word in memory, obtaining an available space in memory having a number of locations corresponding to the size limit of the first dimension of the array, generating a second descriptor word pointing to the second word in the table and setting the second descriptor word to define the size limit of the second dimension as defined by the first word in the table, and storing the second descriptor word in each location of said available space obtained in memory.

Claim 20

The method of allocating memory space in an addressable memory to a multidimensional array in a digital computer system during execution of an object program wherein, as part of the program, memory initially contains a first descriptor word for a first dimension of the array and a table of words containing a word for each of the other dimensions of the array, the first descriptor word pointing to the first word in the table and defining the size limit of the first dimension of the array, the words in the table defining the size limit of the other dimensions of the array, the method comprising the steps of: determining the size limit of the first dimension from the first descriptor word in memory, obtaining an available space in memory having a number of locations corresponding to the size limit of the first dimension of the array, generating a second descriptor word pointing to the second word in the table and setting the second descriptor word to define the size limit of the second dimension as defined by the first word in the table, and storing the second descriptor word in each location of said available space obtained in memory.