diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
@@ -333,6 +333,10 @@
   getLineTableForUnit(DWARFUnit *U,
                       function_ref<void(Error)> RecoverableErrorHandler);
 
+  // Clear the line table object corresponding to a compile unit for memory
+  // management purpose. When it's referred to again, it'll be re-populated.
+  void clearLineTableForUnit(DWARFUnit *U);
+
   DataExtractor getStringExtractor() const {
     return DataExtractor(DObj->getStrSection(), false, 0);
   }
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugLine.h
@@ -304,6 +304,7 @@
   getOrParseLineTable(DWARFDataExtractor &DebugLineData, uint64_t Offset,
                       const DWARFContext &Ctx, const DWARFUnit *U,
                       function_ref<void(Error)> RecoverableErrorHandler);
+  void clearLineTable(uint64_t Offset);
 
   /// Helper to allow for parsing of an entire .debug_line section in sequence.
   class SectionParser {
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -1003,6 +1003,22 @@
                                    RecoverableErrorHandler);
 }
 
+void DWARFContext::clearLineTableForUnit(DWARFUnit *U) {
+  if (!Line)
+    return;
+
+  auto UnitDIE = U->getUnitDIE();
+  if (!UnitDIE)
+    return;
+
+  auto Offset = toSectionOffset(UnitDIE.find(DW_AT_stmt_list));
+  if (!Offset)
+    return;
+
+  uint64_t stmtOffset = *Offset + U->getLineTableOffset();
+  Line->clearLineTable(stmtOffset);
+}
+
 void DWARFContext::parseNormalUnits() {
   if (!NormalUnits.empty())
     return;
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -601,6 +601,10 @@
   return LT;
 }
 
+void DWARFDebugLine::clearLineTable(uint64_t Offset) {
+  LineTableMap.erase(Offset);
+}
+
 static StringRef getOpcodeName(uint8_t Opcode, uint8_t OpcodeBase) {
   assert(Opcode != 0);
   if (Opcode < OpcodeBase)
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -377,6 +377,9 @@
   AddrOffsetSectionBase = None;
   SU = nullptr;
   clearDIEs(false);
+  AddrDieMap.clear();
+  if (DWO)
+    DWO->clear();
   DWO.reset();
 }
 
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugLineTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugLineTest.cpp
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugLineTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugLineTest.cpp
@@ -330,6 +330,82 @@
   // correctly.
 }
 
+#ifdef _AIX
+TEST_P(DebugLineParameterisedFixture, DISABLED_ClearLineValidTable) {
+#else
+TEST_P(DebugLineParameterisedFixture, ClearLineValidTable) {
+#endif
+  if (!setupGenerator(Version))
+    GTEST_SKIP();
+
+  SCOPED_TRACE("Checking Version " + std::to_string(Version) + ", Format " +
+               (Format == DWARF64 ? "DWARF64" : "DWARF32"));
+
+  LineTable &LT = Gen->addLineTable(Format);
+  LT.addExtendedOpcode(9, DW_LNE_set_address, {{0xadd4e55, LineTable::Quad}});
+  LT.addStandardOpcode(DW_LNS_copy, {});
+  LT.addByte(0xaa);
+  LT.addExtendedOpcode(1, DW_LNE_end_sequence, {});
+
+  LineTable &LT2 = Gen->addLineTable(Format);
+  LT2.addExtendedOpcode(9, DW_LNE_set_address, {{0x11223344, LineTable::Quad}});
+  LT2.addStandardOpcode(DW_LNS_copy, {});
+  LT2.addByte(0xbb);
+  LT2.addExtendedOpcode(1, DW_LNE_end_sequence, {});
+  LT2.addExtendedOpcode(9, DW_LNE_set_address, {{0x55667788, LineTable::Quad}});
+  LT2.addStandardOpcode(DW_LNS_copy, {});
+  LT2.addByte(0xcc);
+  LT2.addExtendedOpcode(1, DW_LNE_end_sequence, {});
+
+  generate();
+
+  // Check that we have what we expect before calling clearLineTable().
+  auto ExpectedLineTable = Line.getOrParseLineTable(LineData, 0, *Context,
+                                                    nullptr, RecordRecoverable);
+  ASSERT_TRUE((bool)ExpectedLineTable);
+  EXPECT_FALSE(Recoverable);
+  const DWARFDebugLine::LineTable *Expected = *ExpectedLineTable;
+  checkDefaultPrologue(Version, Format, Expected->Prologue, 16);
+  EXPECT_EQ(Expected->Sequences.size(), 1u);
+
+  uint64_t SecondOffset =
+      Expected->Prologue.sizeofTotalLength() + Expected->Prologue.TotalLength;
+  Recoverable = Error::success();
+  auto ExpectedLineTable2 = Line.getOrParseLineTable(
+      LineData, SecondOffset, *Context, nullptr, RecordRecoverable);
+  ASSERT_TRUE((bool)ExpectedLineTable2);
+  EXPECT_FALSE(Recoverable);
+  const DWARFDebugLine::LineTable *Expected2 = *ExpectedLineTable2;
+  checkDefaultPrologue(Version, Format, Expected2->Prologue, 32);
+  EXPECT_EQ(Expected2->Sequences.size(), 2u);
+
+  // Check that we no longer get the line tables after clearLineTable().
+  Line.clearLineTable(0);
+  Line.clearLineTable(SecondOffset);
+  EXPECT_EQ(Line.getLineTable(0), nullptr);
+  EXPECT_EQ(Line.getLineTable(SecondOffset), nullptr);
+
+  // Check that if the same offset is requested, the contents match what we
+  // had before.
+  Recoverable = Error::success();
+  auto ExpectedLineTable3 = Line.getOrParseLineTable(
+      LineData, 0, *Context, nullptr, RecordRecoverable);
+  ASSERT_TRUE((bool)ExpectedLineTable3);
+  EXPECT_FALSE(Recoverable);
+  const DWARFDebugLine::LineTable *Expected3 = *ExpectedLineTable3;
+  checkDefaultPrologue(Version, Format, Expected3->Prologue, 16);
+  EXPECT_EQ(Expected3->Sequences.size(), 1u);
+
+  Recoverable = Error::success();
+  auto ExpectedLineTable4 = Line.getOrParseLineTable(
+      LineData, SecondOffset, *Context, nullptr, RecordRecoverable);
+  ASSERT_TRUE((bool)ExpectedLineTable4);
+  EXPECT_FALSE(Recoverable);
+  const DWARFDebugLine::LineTable *Expected4 = *ExpectedLineTable4;
+  checkDefaultPrologue(Version, Format, Expected4->Prologue, 32);
+  EXPECT_EQ(Expected4->Sequences.size(), 2u);
+}
+
 #ifdef _AIX
 TEST_F(DebugLineBasicFixture, DISABLED_ErrorForReservedLength) {
 #else