[DebugInfo][RemoveDIs] Add flag to use "new" debug-info in opt by jmorse · Pull Request #71937 · llvm/llvm-project (original) (raw)

@llvm/pr-subscribers-debuginfo

Author: Jeremy Morse (jmorse)

Changes

Our option to turn on the non-intrinsic form of debug-info (--experimental-debuginfo-iterators) currently requires that LLVM is built with the LLVM_EXPERIMENTAL_DEBUGINFO_ITERATORS cmake flag enabled, so that some (slight) performance regressions aren't on-by-default during the prototype/testing period. However, we still want to be able to optionally run tests, if support is built into LLVM.

To allow optionally exercising the non-intrinsic debug-info code, this patch adds --try-experimental-debuginfo-iterators to opt, which turns the --experimental-debuginfo-iterators flag on if support is built in, or leaves it off. This means we can run tests that:

• Use normal dbg.value intrinsics if there's no support, or
• Uses non-instruction DPValues if there is support.

Which means we can start getting test coverage of DPValues/RemoveDIs behaviour, from in-tree tests, on our RemoveDIs buildbot. All the code to do with automagically converting from one form to the other landed in 10a9e74.

Full diff: https://github.com/llvm/llvm-project/pull/71937.diff

1 Files Affected:

• (modified) llvm/tools/opt/opt.cpp (+19)

diff --git a/llvm/tools/opt/opt.cpp b/llvm/tools/opt/opt.cpp index bb6627364442ef7..129f754eedda71d 100644 --- a/llvm/tools/opt/opt.cpp +++ b/llvm/tools/opt/opt.cpp @@ -279,6 +279,12 @@ static cl::liststd::string PassPlugins("load-pass-plugin", cl::desc("Load passes from plugin library"));

+static cl::opt TryUseNewDbgInfoFormat("try-experimental-debuginfo-iterators",

• cl::desc("Enable debuginfo iterator positions, if they're built in"),

• cl::init(false));

• +extern cl::opt UseNewDbgInfoFormat;

• //===----------------------------------------------------------------------===// // CodeGen-related helper functions. // @@ -438,6 +444,19 @@ int main(int argc, char **argv) { initializeReplaceWithVeclibLegacyPass(Registry); initializeJMCInstrumenterPass(Registry);

• // RemoveDIs debug-info transition: tests may request that we /try/ to use the

• // new debug-info format, if it's built in.

• if (TryUseNewDbgInfoFormat) { +#ifdef EXPERIMENTAL_DEBUGINFO_ITERATORS

• // If LLVM was built with support for this, turn the new debug-info format

• // on.

• UseNewDbgInfoFormat = true;

+#else

• // It it wasn't, do nothing.
• ;

+#endif

• }
• SmallVector<PassPlugin, 1> PluginList; PassPlugins.setCallback([&](const std::string &PluginPath) { auto Plugin = PassPlugin::Load(PluginPath);