[enigmo]

this was a common practice at Microsoft in the mid 90s, maybe 95-97ish. the set of apps involved were called BBT: "Basic Block Tools". Windows, SQL Server, among others, were post processed with profiling data. it also deduped basic blocks, reducing binary bloat from inlining even without profiling data. just needed some additional info in the debug symbols to work.

[jeffbee]

Identical code folding still breaks debugging with modern llvm. It can make it seem like the call came from an impossible place in a stack sample. Is it something that Microsoft solved long ago?