hoy marked an inline comment as done. hoy added a comment. In D86502#2245460 <https://reviews.llvm.org/D86502#2245460>, @wmi wrote:
>> The early instrumentation also allows the inliner to duplicate probes for >> inlined instances. When a probe along with the other instructions of a >> callee function are inlined into its caller function, the GUID of the callee >> function goes with the probe. This allows samples collected on inlined >> probes to be reported for the original callee function. > > Just get a question from reading the above. Suppose `A` only has one BB and > the BB has one PseudoProbe in it. If function `A` is inlined into `B1` and > `B2` and both `B1` and `B2` inlined into `C`, the PseudoProbe from `A` will > have two copies in `C` both carrying GUID of `A`. How the samples collected > from `A` inlined into `B1` inlined into `C` are categorized differently from > `A` inlined into `B2` inlined into `C`, especially when debug information is > not enabled (so no inline stack information in the binary)? This is a very good question. Inlined functions are differentiated by their original callsites. A pseudo probe is allocated for each callsite in the `SampleProfileProbe` pass. Nested inlining will produce a stack of pseudo probes, similar with the Dwarf inline stack. The work is not included in the first set of patches. ================ Comment at: llvm/include/llvm/Passes/PassBuilder.h:67-69 + // Pseudo probe instrumentation should only work with autoFDO or no FDO. + assert(!this->PseudoProbeForProfiling || this->Action == NoAction || + this->Action == SampleUse); ---------------- wmi wrote: > Need it to work with more types of action for example instrumentation FDO or > cs instrumentation FDO. For instrumentation FDO optimized binary, we may want > to collect AutoFDO profile for it for performance comparison, enhance the > intrumentation profile with AutoFDO profile to make the profile more > production representative, ... > > Currently debug information based AutoFDO supports it. I see. I just removed this assert and the let assert above handle both `DebugInfoForProfiling` and `PseudoProbeForProfiling`. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D86502/new/ https://reviews.llvm.org/D86502 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
