[RemoveDIs][NFC] Introduce DbgRecord base class [1/3] (#78252)

Patch 1 of 3 to add llvm.dbg.label support to the RemoveDIs project. The
patch stack adds a new base class

    -> 1. Add DbgRecord base class for DPValue and the not-yet-added
          DPLabel class.
       2. Add the DPLabel class.
       3. Enable dbg.label conversion and add support to passes.

Patches 1 and 2 are NFC.

In the near future we also will rename DPValue to DbgVariableRecord and
DPLabel to DbgLabelRecord, at which point we'll overhaul the function
names too. The name DPLabel keeps things consistent for now.

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 32a25b4..4036f18 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -8505,7 +8505,7 @@ bool CodeGenPrepare::fixupDbgValue(Instruction *I) {
 
 bool CodeGenPrepare::fixupDPValuesOnInst(Instruction &I) {
   bool AnyChange = false;
-  for (DPValue &DPV : I.getDbgValueRange())
+  for (DPValue &DPV : DPValue::filter(I.getDbgValueRange()))
     AnyChange |= fixupDPValue(DPV);
   return AnyChange;
 }
@@ -8618,7 +8618,8 @@ bool CodeGenPrepare::placeDbgValues(Function &F) {
 
       // If this isn't a dbg.value, process any attached DPValue records
       // attached to this instruction.
-      for (DPValue &DPV : llvm::make_early_inc_range(Insn.getDbgValueRange())) {
+      for (DPValue &DPV : llvm::make_early_inc_range(
+               DPValue::filter(Insn.getDbgValueRange()))) {
         if (DPV.Type != DPValue::LocationType::Value)
           continue;
         DbgProcessor(&DPV, &Insn);