[llvm-bolt] Way to know whether the binary was converted by BOLT

[corona10]

For example, CPython failed to pass the test_gdb if the binary is converted by BOLT and it's intended.
But it would be great if there is a way to know if the binary was converted by BOLT.

[corona10]

cc @aaupov

[corona10]

llvm-project/bolt/lib/Rewrite/RewriteInstance.cpp

Lines 461 to 468 in 728d817

	if (!opts::HeatmapMode &&
	!(opts::AggregateOnly && BAT->enabledFor(InputFile)) &&
	(SectionName.startswith(getOrgSecPrefix()) ||
	SectionName == getBOLTTextSectionName()))
	return createStringError(
	errc::function_not_supported,
	"BOLT-ERROR: input file was processed by BOLT. Cannot re-optimize");
	}

It looks like there is a section that can be a hint for it.

[llvmbot]

@llvm/issue-subscribers-bolt

[aaupov]

readelf -p .note.bolt_info <executable> | grep BOLT

Example output:

  [    10]  BOLT revision: <unknown>, command line: /home/worker/bolt-worker2/bolt-x86_64-ubuntu-shared/build/bin/llvm-bolt /home/worker/bolt-worker2/bolt-x86_64-ubuntu-shared/build/tools/bolt/test/Output/re-optimize.test.tmp.exe -o /home/worker/bolt-worker2/bolt-x86_64-ubuntu-shared/build/tools/bolt/test/Output/re-optimize.test.tmp

[aaupov]

The section is added by default but can be omitted if -bolt-info=0 is passed

[corona10]

Okay Thanks looks like it should be solved by reading self-binary :)