llvm / llvm/llvm-project

Out-of-bounds tracking in unknown regions during user library optimization reached 98.4%. Is this related to Address Space Layout Randomization (ASLR)?

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Description

When processing profile data from user libraries using the perf2bolt tool, a warning _"PERF2BOLT: out of range traces involving unknown regions: 15765671 (98.4%) "_ occurred, causing the profile data to fail to take effect. When ASLR is disabled in the data collection scenario, this metric decreases. Is this coincidental? Has anyone else encountered a similar issue?

The specific process is as follows:
```
perf2bolt --pa -p=libxx.profdata" -o libxx.fdata libxx.symbol"
BOLT-INFO: shared object or position-independent executable detected
BOLT-INFO: shared object or position-independent executable detected
PERF2BOLT: Starting data aggregation job for libxx.profdata
BOLT-INFO: Target architecture: aarch64
BOLT-INFO: BOLT version: e03a7c124d50fa9449a81fe21cc958a18919a4ea
BOLT-INFO: first alloc address is 0x0
BOLT-INFO: creating new program header table at address 0x200000, offset 0x200000
BOLT-INFO: enabling relocation mode
BOLT-INFO: enabling strict relocation mode for aggregation purposes
BOLT-INFO: pre-processing profile using perf data aggregator
PERF2BOLT: parsing pre-aggregated profile...
PERF2BOLT: read 2116 aggregated LBR entries
PERF2BOLT: processing branch events...
PERF2BOLT: traces mismatching disassembled function contents: 0 (0.0%)
PERF2BOLT: **out of range traces involving unknown regions: 15765671 (98.4%)**
PERF2BOLT: wrote 70 objects and 0 memory objects to libxx.fdata
BOLT-INFO: 0 out of 381 functions in the binary (0.0%) have non-empty execution profile
BOLT-WARNING: the output profile is empty or the --profile-density-cutoff-hot option is set too low. Please check your command.
BOLT-INFO: Functions with density >= 0.0 account for 99.00% total sample counts.
```
- Result: SUCCESS (took 0 seconds)
- Output size: 4.0K

Out-of-bounds tracking in unknown regions during user library optimization reached 98.4%. Is this related to Address Space Layout Randomization (ASLR)?

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