HyperLink   A Novel Breakpoint Implementation Scheme for Debugging Optimized Code
Publication Year:
  Le-Chun Wu, Wen-mei Hwu
  IMPACT Technical Report, IMPACT-98-01, University of Illinois, Urbana, IL 1998

Providing a clear and correct source-level debugger for programmers to debug highly optimized code has become a necessity with executable binaries increasingly generated by compilers which incorporate advanced optimization techniques. Implementing source breakpoints is essential for providing such a debugger. In this paper, a novel source breakpoint implementation scheme for debugging optimized code is proposed. The approach is aimed at solving the fundamental problem suffered by the traditional scheme. By taking over the control early and executing instructions under a new forward recovery model, the debugger can preserve and gather the required program states. With this information accumulated and the help of a data location tracking method, the expected values of user variables can be recovered at source breakpoints. In order to facilitate this new breakpoint implementation scheme, additional information needs to be generated and maintained during compilation. The compiler support for our approach is also described.