Abstract: A computer-implemented method estimates a memory reuse-distance profile for a program executing on a processing computer that includes a data memory, a hardware performance monitoring unit (PMU), and a debug register. During program execution, the PMU periodically samples accesses of the data memory. For each periodic access, a watchpoint in the debug register is armed for an address of the data memory associated with the corresponding periodic access wherein the debug register traps on a next access of the address. A total number of accesses to the data memory occurring between the periodic access and the next access of the address is determined. A stack reuse-distance histogram is generated using each of the total number of accesses determined as the program executes.

Abstract: Verification of low-level rewriters such as binary rewriters involves “vanilla” rewriting a file to generate a rewritten low-level file without performing any optimization, compaction, or other substantive low-level code transformation during the rewrite. Then the metadata of the original low-level file is automatically compared with matching metadata of the rewritten low-level file for semantic equivalence. A properly functioning rewriter produces semantically equivalent files, whereas a defective rewriter may produce files whose metadata semantics differ. Comparison may distinguish composite metadata entities from self-contained metadata entities, and transitive closures of metadata may be compared. Comparison may also test for bitwise equality of self-contained metadata entities, and test for equality between respective flags, strings, fields, and/or methods of the original and rewritten files.

Abstract: Verification of low-level rewriters such as binary rewriters involves “vanilla” rewriting a file to generate a rewritten low-level file without performing any optimization, compaction, or other substantive low-level code transformation during the rewrite. Then the metadata of the original low-level file is automatically compared with matching metadata of the rewritten low-level file for semantic equivalence. A properly functioning rewriter produces semantically equivalent files, whereas a defective rewriter may produce files whose metadata semantics differ. Comparison may distinguish composite metadata entities from self-contained metadata entities, and transitive closures of metadata may be compared. Comparison may also test for bitwise equality of self-contained metadata entities, and test for equality between respective flags, strings, fields, and/or methods of the original and rewritten files.