Profiled JIT dump lacks machine code

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Hi all,

I would like to profile Julia functions at instruction level using Linux perf. However, I cannot see disassembled machine code in the result. As you can see below, the disassembled code just after julia_partition!_53 is omitted with dots:

~/tmp $ env ENABLE_JITPROFILING=1 perf record -k mono julia-1.6 -e 'sort(randn(100_000_000))'
[ perf record: Woken up 5 times to write data ]
[ perf record: Captured and wrote 1.302 MB perf.data (33900 samples) ]
~/tmp $ perf inject --jit --input perf.data --output perf.jit.data
PERFILE2h⏎                                                                                                                     
~/tmp $ perf annotate -i perf.jit.data | head -20
 Percent |      Source code & Disassembly of jitted-304678-25.so for cycles:u (12117 samples, percent: local period)
--------------------------------------------------------------------------------------------------------------------
         :
         :
         :
         :       Disassembly of section .text:
         :
         :       0000000000000040 <julia_partition!_53>:
         :       ...
 Percent |      Source code & Disassembly of jitted-304678-31.so for cycles:u (11920 samples, percent: local period)
--------------------------------------------------------------------------------------------------------------------
         :
         :
         :
         :       Disassembly of section .text:
         :
         :       0000000000000040 <julia_partition!_45>:
         :       ...
 Percent |      Source code & Disassembly of jitted-304678-34.so for cycles:u (1587 samples, percent: local period)
-------------------------------------------------------------------------------------------------------------------
~/tmp $ julia-1.6 -q
julia> versioninfo()
Julia Version 1.6.0-beta1
Commit b84990e1ac (2021-01-08 12:42 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: AMD Ryzen 9 3950X 16-Core Processor
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-11.0.0 (ORCJIT, znver2)
Environment:
  JULIA_PROJECT = @.

julia>

The relevant part of the generated object file seems to be filled with zeros:

~/tmp $ hexdump -C ~/.debug/jit/llvm-IR-jit-20210131-4fc7cb/jitted-304678-25.so | head
00000000  7f 45 4c 46 02 01 01 00  00 00 00 00 00 00 00 00  |.ELF............|
00000010  03 00 3e 00 01 00 00 00  40 00 00 00 00 00 00 00  |..>.....@.......|
00000020  00 00 00 00 00 00 00 00  18 05 00 00 00 00 00 00  |................|
00000030  00 00 00 00 40 00 00 00  00 00 40 00 09 00 02 00  |....@.....@.....|
00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000170  00 00 2e 74 65 78 74 00  2e 73 68 73 74 72 74 61  |...text..shstrta|
00000180  62 00 2e 73 79 6d 74 61  62 00 2e 73 74 72 74 61  |b..symtab..strta|
00000190  62 00 2e 6e 6f 74 65 2e  67 6e 75 2e 62 75 69 6c  |b..note.gnu.buil|
000001a0  64 2d 69 64 00 2e 64 65  62 75 67 5f 6c 69 6e 65  |d-id..debug_line|

What I expected is disassembled code with profiling annotations like shown at the bottom of this page Profiling with Perf - Wasmtime.

Any hints are appreciated.

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