llvm_bolt --instrument can not exe __bolt_instr_start #163339
Description
for libc.so.6 I want to instrument it to collect prof,fdata,Howerver it failed
llvm-bolt libc.so.6 -instrument --instrumentation-sleep-time=30 -o libc.so.6.new
- BOLT-INFO: shared object or position-independent executable detected
- BOLT-INFO: Target architecture: aarch64
- BOLT-INFO: BOLT version: 6abb626
- BOLT-INFO: first alloc address is 0x0
- BOLT-INFO: creating new program header table at address 0x200000, offset 0x200000
- BOLT-WARNING: debug info will be stripped from the binary. Use -update-debug-sections to keep it.
- BOLT-INFO: enabling relocation mode
- BOLT-INFO: forcing -jump-tables=move for instrumentation
- BOLT-INFO: number of removed linker-inserted veneers: 0
- BOLT-INFO: 0 out of 3238 functions in the binary (0.0%) have non-empty execution profile
- BOLT-INSTRUMENTER: Number of indirect call site descriptors: 601
- BOLT-INSTRUMENTER: Number of indirect call target descriptors: 3212
- BOLT-INSTRUMENTER: Number of function descriptors: 3202
- BOLT-INSTRUMENTER: Number of branch counters: 25770
- BOLT-INSTRUMENTER: Number of ST leaf node counters: 16269
- BOLT-INSTRUMENTER: Number of direct call counters: 378
- BOLT-INSTRUMENTER: Total number of counters: 42417
- BOLT-INSTRUMENTER: Total size of counters: 339336 bytes (static alloc memory)
- BOLT-INSTRUMENTER: Total size of string table emitted: 60391 bytes in file
- BOLT-INSTRUMENTER: Total size of descriptors: 2752512 bytes in file
- BOLT-INSTRUMENTER: Profile will be saved to file /tmp/prof.fdata
- BOLT-INFO: removed 310 empty blocks
- BOLT-INFO: UCE removed 43 blocks and 4040 bytes of code
- BOLT-INFO: Starting stub-insertion pass
- BOLT-INFO: Inserted 0 stubs in the hot area and 0 stubs in the cold area. Shared 0 times, iterated 1 times.
- BOLT-INFO: padding code to 0x800000 to accommodate hot text
- BOLT-INFO: output linked against instrumentation runtime library, lib entry point is 0x8d99b8
- BOLT-INFO: clear procedure is 0x8d81c0
- BOLT-INFO: patched build-id (flipped last bit)
- BOLT-INFO: setting __bolt_runtime_start to 0x8d99b8
- BOLT-INFO: setting __bolt_runtime_fini to 0x8d9ae8
- BOLT-INFO: setting __hot_start to 0x400000
- BOLT-INFO: setting __hot_end to 0x6c9244
`
i found that it does not exe function __bolt_instr_start so cannot generata prof.fdata
readelf -h libc.so.6
Entry point address: 0x8d99b8
8d99b8: b0000000 adrp x0, 8da000 <__bolt_runtime_fini+0x518>