On 8/14/19 3:52 PM, Ismail Bennani via lldb-dev wrote: > Hi everyone, > > I’m Ismail, a compiler engineer intern at Apple. As a part of my internship, > I'm adding Fast Conditional Breakpoints to LLDB, using code patching. > > ... > > Since all the registers are already mapped to a structure, I should > be able to support more __DWARF Operations__ in the future. > > After collecting some metrics on the __Clang__ binary, built at __-O0__, > the debug info shows that __99%__ of the most used DWARF Operations are : > > |DWARF Operation| Occurrences | > |---------------|---------------------------| > |DW\_OP_fbreg | 2 114 612 | > |DW\_OP_reg | 820 548 | > |DW\_OP_constu | 267 450 | > |DW\_OP_addr | 17 370 | > > | __Top 4__ | __3 219 980 Occurrences__ | > |---------------|---------------------------| > | __Total__ | __3 236 859 Occurrences__ | > > Those 4 operations are the one that I'll support for now. > To support more complex expressions, we would need to JIT-compile > a DWARF expression interpreter.
First, this all sounds really useful. Out of curiosity, how do these statistics change if you compile Clang with -O1? Many of my users need to debug slightly-optimized code. -Hal -- Hal Finkel Lead, Compiler Technology and Programming Languages Leadership Computing Facility Argonne National Laboratory _______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
