4 files changed, 26 insertions, 7 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 4e90c10e3e9..e40541e57d5 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -964,8 +964,8 @@ DIE &DwarfCompileUnit::constructCallSiteEntryDIE(
     addAddress(CallSiteDIE, getDwarf5OrGNUAttr(dwarf::DW_AT_call_target),
                MachineLocation(CallReg));
   } else {
-    DIE *CalleeDIE = getOrCreateSubprogramDIE(CalleeSP);
-    assert(CalleeDIE && "Could not create DIE for call site entry origin");
+    DIE *CalleeDIE = getDIE(CalleeSP);
+    assert(CalleeDIE && "Could not find DIE for call site entry origin");
     addDIEEntry(CallSiteDIE, getDwarf5OrGNUAttr(dwarf::DW_AT_call_origin),
                 *CalleeDIE);
   }
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 708cef896b5..4def44cd776 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -535,6 +535,14 @@ void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &SrcCU,
   }
 }
 
+DIE &DwarfDebug::constructSubprogramDefinitionDIE(const DISubprogram *SP) {
+  DICompileUnit *Unit = SP->getUnit();
+  assert(SP->isDefinition() && "Subprogram not a definition");
+  assert(Unit && "Subprogram definition without parent unit");
+  auto &CU = getOrCreateDwarfCompileUnit(Unit);
+  return *CU.getOrCreateSubprogramDIE(SP);
+}
+
 /// Try to interpret values loaded into registers that forward parameters
 /// for \p CallMI. Store parameters with interpreted value into \p Params.
 static void collectCallSiteParameters(const MachineInstr *CallMI,
@@ -745,6 +753,15 @@ void DwarfDebug::constructCallSiteEntryDIEs(const DISubprogram &SP,
         if (!CalleeDecl || !CalleeDecl->getSubprogram())
           continue;
         CalleeSP = CalleeDecl->getSubprogram();
+
+        if (CalleeSP->isDefinition()) {
+          // Ensure that a subprogram DIE for the callee is available in the
+          // appropriate CU.
+          constructSubprogramDefinitionDIE(CalleeSP);
+        } else {
+          assert(CU.getDIE(CalleeSP) &&
+                 "Expected declaration subprogram DIE for callee");
+        }
       }
 
       // TODO: Omit call site entries for runtime calls (objc_msgSend, etc).
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 6f54c528a50..2e547f12412 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -437,6 +437,9 @@ class DwarfDebug : public DebugHandlerBase {
   /// Construct a DIE for this abstract scope.
   void constructAbstractSubprogramScopeDIE(DwarfCompileUnit &SrcCU, LexicalScope *Scope);
 
+  /// Construct a DIE for the subprogram definition \p SP and return it.
+  DIE &constructSubprogramDefinitionDIE(const DISubprogram *SP);
+
   /// Construct DIEs for call site entries describing the calls in \p MF.
   void constructCallSiteEntryDIEs(const DISubprogram &SP, DwarfCompileUnit &CU,
                                   DIE &ScopeDIE, const MachineFunction &MF);
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 86522a85427..58d7a4eaa7e 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -188,8 +188,9 @@ int64_t DwarfUnit::getDefaultLowerBound() const {
 
 /// Check whether the DIE for this MDNode can be shared across CUs.
 bool DwarfUnit::isShareableAcrossCUs(const DINode *D) const {
-  // When the MDNode can be part of the type system, the DIE can be shared
-  // across CUs.
+  // When the MDNode can be part of the type system (this includes subprogram
+  // declarations *and* subprogram definitions, even local definitions), the
+  // DIE must be shared across CUs.
   // Combining type units and cross-CU DIE sharing is lower value (since
   // cross-CU DIE sharing is used in LTO and removes type redundancy at that
   // level already) but may be implementable for some value in projects
@@ -197,9 +198,7 @@ bool DwarfUnit::isShareableAcrossCUs(const DINode *D) const {
   // together.
   if (isDwoUnit() && !DD->shareAcrossDWOCUs())
     return false;
-  return (isa<DIType>(D) ||
-          (isa<DISubprogram>(D) && !cast<DISubprogram>(D)->isDefinition())) &&
-         !DD->generateTypeUnits();
+  return (isa<DIType>(D) || isa<DISubprogram>(D)) && !DD->generateTypeUnits();
 }
 
 DIE *DwarfUnit::getDIE(const DINode *D) const {