1 files changed, 25 insertions, 10 deletions
diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
index c4f4d4c2870..22a8e73e4af 100644
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -840,6 +840,10 @@ void MCAssembler::layout(MCAsmLayout &Layout) {
           getBackend().shouldInsertFixupForCodeAlign(*this, Layout, *AF);
         }
         continue;
+      } else if (auto *FragWithFixups =
+                     dyn_cast<MCDwarfCallFrameFragment>(&Frag)) {
+        Fixups = FragWithFixups->getFixups();
+        Contents = FragWithFixups->getContents();
       } else
         llvm_unreachable("Unknown fragment with fixups!");
       for (const MCFixup &Fixup : Fixups) {
@@ -969,13 +973,9 @@ bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout,
   MCContext &Context = Layout.getAssembler().getContext();
   uint64_t OldSize = DF.getContents().size();
   int64_t AddrDelta;
-  bool Abs;
-  if (getBackend().requiresDiffExpressionRelocations())
-    Abs = DF.getAddrDelta().evaluateAsAbsolute(AddrDelta, Layout);
-  else {
-    Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout);
-    assert(Abs && "We created a line delta with an invalid expression");
-  }
+  bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout);
+  assert(Abs && "We created a line delta with an invalid expression");
+  (void)Abs;
   int64_t LineDelta;
   LineDelta = DF.getLineDelta();
   SmallVectorImpl<char> &Data = DF.getContents();
@@ -983,7 +983,7 @@ bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout,
   raw_svector_ostream OSE(Data);
   DF.getFixups().clear();
 
-  if (Abs) {
+  if (!getBackend().requiresDiffExpressionRelocations()) {
     MCDwarfLineAddr::Encode(Context, getDWARFLinetableParams(), LineDelta,
                             AddrDelta, OSE);
   } else {
@@ -1017,10 +1017,25 @@ bool MCAssembler::relaxDwarfCallFrameFragment(MCAsmLayout &Layout,
   bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout);
   assert(Abs && "We created call frame with an invalid expression");
   (void) Abs;
-  SmallString<8> &Data = DF.getContents();
+  SmallVectorImpl<char> &Data = DF.getContents();
   Data.clear();
   raw_svector_ostream OSE(Data);
-  MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE);
+  DF.getFixups().clear();
+
+  if (getBackend().requiresDiffExpressionRelocations()) {
+    uint32_t Offset;
+    uint32_t Size;
+    MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE, &Offset,
+                                          &Size);
+    if (Size) {
+      DF.getFixups().push_back(MCFixup::create(
+          Offset, &DF.getAddrDelta(),
+          MCFixup::getKindForSizeInBits(Size /*In bits.*/, false /*isPCRel*/)));
+    }
+  } else {
+    MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE);
+  }
+
   return OldSize != Data.size();
 }