Abstract: Methods to improve optimization of compilation are presented. In one embodiment, a method includes identifying one or more optimization speculations with respect to a code region and speculatively performing transformation on an intermediate representation of the code region in accordance with an optimization speculation. The method includes generating an advice message corresponding to the optimization speculation and displaying the advice message if the optimization speculation results in an improved compilation result.

Abstract: Methods and apparatus to provide loop parallelization based on loop splitting and/or index array are described. In one embodiment, one or more split loops, corresponding to an original loop, are generated based on the mis-speculation information. In another embodiment, a plurality of subloops are generated from an original loop based on an index array. Other embodiments are also described.

Abstract: Methods and apparatus to data dependence testing for loop fusion, e.g., with code replication, array contraction, and/or loop interchange, are described. In one embodiment, a compiler may optimize code for efficient execution during run-time by testing for dependencies associated with improving memory locality through code replication in loops that enable various loop transformations. Other embodiments are also described.

Abstract: A system and method are configured to apply region level optimizations to a selected region of source code rather than loop level optimizations to a loop or loop nest. The region may include an outer loop, a plurality of inner loops and at least one control code. If the region includes an exceptional control flow statement and/or a procedure call, speculative region-level multi-versioning may be applied.

Abstract: In one embodiment of the invention, a method for fusing a first loop nested in a first IF statement with a second loop nested in a second IF statement without the use of modified and referenced (mod-ref) information to determine if certain conditional statements in the IF statements retain variable values.

Abstract: Provided are a method, system, and article of manufacture improving data locality and parallelism by code replication and array contraction. Source code including an array of elements referenced using at least two indices is processed. The array is nested within multiple loops, wherein at least two of the loops perform iterations with respect to the indices of the array, wherein the index incremented in at least one innermost loop of the loops does not comprise a leftmost index in the array. The source code is transformed to object code by performing operations including fusing at least two innermost loops of the loops in object code generated by compiling the source code by replicating statements from at least one of the innermost loops into a fused innermost loop and performing loop interchange in the object code to have the fused innermost loop provide iterations with respect to the leftmost index in the array.

Abstract: Methods and apparatus to provide loop parallelization based on loop splitting and/or index array are described. In one embodiment, one or more split loops, corresponding to an original loop, are generated based on the mis-speculation information. In another embodiment, a plurality of subloops are generated from an original loop based on an index array. Other embodiments are also described.

Abstract: A system and method are configured to apply region level optimizations to a selected region of source code rather than loop level optimizations to a loop or loop nest. The region may include an outer loop, a plurality of inner loops and at least one control code. If the region includes an exceptional control flow statement and/or a procedure call, speculative region-level multi-versioning may be applied.

Abstract: Methods to improve optimization of compilation are presented. In one embodiment, a method includes identifying one or more optimization speculations with respect to a code region and speculatively performing transformation on an intermediate representation of the code region in accordance with an optimization speculation. The method includes generating an advice message corresponding to the optimization speculation and displaying the advice message if the optimization speculation results in an improved compilation result.

Abstract: In one embodiment of the invention, a method for fusing a first loop nested in a first IF statement with a second loop nested in a second IF statement without the use of modified and referenced (mod-ref) information to determine if certain conditional statements in the IF statements retain variable values.

Abstract: Methods and apparatus to data dependence testing for loop fusion, e.g., with code replication, array contraction, and/or loop interchange, are described. In one embodiment, a compiler may optimize code for efficient execution during run-time by testing for dependencies associated with improving memory locality through code replication in loops that enable various loop transformations. Other embodiments are also described.

Abstract: Provided are a method, system, and article of manufacture improving data locality and parallelism by code replication and array contraction. Source code including an array of elements referenced using at least two indices is processed. The array is nested within multiple loops, wherein at least two of the loops perform iterations with respect to the indices of the array, wherein the index incremented in at least one innermost loop of the loops does not comprise a leftmost index in the array. The source code is transformed to object code by performing operations including fusing at least two innermost loops of the loops in object code generated by compiling the source code by replicating statements from at least one of the innermost loops into a fused innermost loop and performing loop interchange in the object code to have the fused innermost loop provide iterations with respect to the leftmost index in the array.

Abstract: An apparatus, method, and program product for optimizing code that contains dynamically-allocated memory. The aliasing behavior of internal pointers of dynamically-allocated memory is used to disambiguate memory accesses and to eliminate false data dependencies. It is determined whether a dynamically-allocated array will behave like a statically-allocated array throughout the entire program execution once it has been allocated. This determination is used to improve the instruction scheduling efficiency, which yields better performance.

Abstract: An apparatus, method, and program product for optimizing code that contains dynamically-allocated memory. The aliasing behavior of internal pointers of dynamically-allocated memory is used to disambiguate memory accesses and to eliminate false data dependencies. It is determined whether a dynamically-allocated array will behave like a statically-allocated array throughout the entire program execution once it has been allocated. This determination is used to improve the instruction scheduling efficiency, which yields better performance.

Abstract: A subscript table mapping system for optimizing the compilation of certain Fortran 90 array construction and array manipulation transformation functions. The subscript table data object of this invention is used to perform the three compiler optimizations, including subscript dependency analysis, subscript table transformation and optimized code generation. Application of a simple subscript mapping function tailored to the particular intrinsic Fortran 90 array variable transformation function permits compilation of executable binary code that saves substantial processing steps and data storage space by avoiding during execution the usual requirement for temporary storage of abstract transformational array variables.