Add option to limit Debugify to locations (omitting variables)

Summary:
It can be helpful to test behaviour w.r.t locations without having DEBUG_VALUE
around. In particular, because DEBUG_VALUE has the potential to change CodeGen
behaviour (e.g. hasOneUse() vs hasOneNonDbgUse()) while locations generally
don't.

Reviewers: aprantl, bogner

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77438

1 files changed, 14 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/Debugify.cpp b/llvm/lib/Transforms/Utils/Debugify.cpp
index b1274d9..a9cdf65 100644
--- a/llvm/lib/Transforms/Utils/Debugify.cpp
+++ b/llvm/lib/Transforms/Utils/Debugify.cpp
@@ -30,6 +30,17 @@ namespace {
 cl::opt<bool> Quiet("debugify-quiet",
                     cl::desc("Suppress verbose debugify output"));
 
+enum class Level {
+  Locations,
+  LocationsAndVariables
+};
+cl::opt<Level> DebugifyLevel(
+    "debugify-level", cl::desc("Kind of debug info to add"),
+    cl::values(clEnumValN(Level::Locations, "locations", "Locations only"),
+               clEnumValN(Level::LocationsAndVariables, "location+variables",
+                          "Locations and Variables")),
+    cl::init(Level::LocationsAndVariables));
+
 raw_ostream &dbg() { return Quiet ? nulls() : errs(); }
 
 uint64_t getAllocSizeInBits(Module &M, Type *Ty) {
@@ -100,6 +111,9 @@ bool applyDebugifyMetadata(Module &M,
       for (Instruction &I : BB)
         I.setDebugLoc(DILocation::get(Ctx, NextLine++, 1, SP));
 
+      if (DebugifyLevel < Level::LocationsAndVariables)
+        continue;
+
       // Inserting debug values into EH pads can break IR invariants.
       if (BB.isEHPad())
         continue;