[RemoveDIs][DebugInfo] Create overloads of debug intrinsic utilities for DPValues (#78313)

In preparation for the major chunk of the assignment tracking
implementation, this patch adds a new set of overloaded versions of
existing functions that take DbgVariableIntrinsics, with the overloads
taking DPValues. This is used specifically to allow us to use generic code
to handle both DbgVariableIntrinsics and DPValues, reducing code
duplication. This patch doesn't actually add the uses of these functions.

1 files changed, 38 insertions, 1 deletions

diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 312d670..c95b40a 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -163,6 +163,18 @@ DebugLoc llvm::getDebugValueLoc(DbgVariableIntrinsic *DII) {
   return DILocation::get(DII->getContext(), 0, 0, Scope, InlinedAt);
 }
 
+DebugLoc llvm::getDebugValueLoc(DPValue *DPV) {
+  // Original dbg.declare must have a location.
+  const DebugLoc &DeclareLoc = DPV->getDebugLoc();
+  MDNode *Scope = DeclareLoc.getScope();
+  DILocation *InlinedAt = DeclareLoc.getInlinedAt();
+  // Because no machine insts can come from debug intrinsics, only the scope
+  // and inlinedAt is significant. Zero line numbers are used in case this
+  // DebugLoc leaks into any adjacent instructions. Produce an unknown location
+  // with the correct scope / inlinedAt fields.
+  return DILocation::get(DPV->getContext(), 0, 0, Scope, InlinedAt);
+}
+
 //===----------------------------------------------------------------------===//
 // DebugInfoFinder implementations.
 //===----------------------------------------------------------------------===//
@@ -1813,6 +1825,31 @@ void at::deleteAll(Function *F) {
     DAI->eraseFromParent();
 }
 
+/// Get the FragmentInfo for the variable if it exists, otherwise return a
+/// FragmentInfo that covers the entire variable if the variable size is
+/// known, otherwise return a zero-sized fragment.
+static DIExpression::FragmentInfo
+getFragmentOrEntireVariable(const DPValue *DPV) {
+  DIExpression::FragmentInfo VariableSlice(0, 0);
+  // Get the fragment or variable size, or zero.
+  if (auto Sz = DPV->getFragmentSizeInBits())
+    VariableSlice.SizeInBits = *Sz;
+  if (auto Frag = DPV->getExpression()->getFragmentInfo())
+    VariableSlice.OffsetInBits = Frag->OffsetInBits;
+  return VariableSlice;
+}
+
+static DIExpression::FragmentInfo
+getFragmentOrEntireVariable(const DbgVariableIntrinsic *DVI) {
+  DIExpression::FragmentInfo VariableSlice(0, 0);
+  // Get the fragment or variable size, or zero.
+  if (auto Sz = DVI->getFragmentSizeInBits())
+    VariableSlice.SizeInBits = *Sz;
+  if (auto Frag = DVI->getExpression()->getFragmentInfo())
+    VariableSlice.OffsetInBits = Frag->OffsetInBits;
+  return VariableSlice;
+}
+
 bool at::calculateFragmentIntersect(
     const DataLayout &DL, const Value *Dest, uint64_t SliceOffsetInBits,
     uint64_t SliceSizeInBits, const DbgAssignIntrinsic *DAI,
@@ -1910,7 +1947,7 @@ bool at::calculateFragmentIntersect(
   if (DAI->isKillAddress())
     return false;
 
-  DIExpression::FragmentInfo VarFrag = DAI->getFragmentOrEntireVariable();
+  DIExpression::FragmentInfo VarFrag = getFragmentOrEntireVariable(DAI);
   if (VarFrag.SizeInBits == 0)
     return false; // Variable size is unknown.