Put back the emitDwarfAdvanceFrameAddr () method into MCStreamer which was moved into MCObjectStreamer so it can be used whhen emitting assembly as well.

3 files changed, 36 insertions, 1 deletions

diff --git a/llvm/include/llvm/MC/MCObjectStreamer.h b/llvm/include/llvm/MC/MCObjectStreamer.h
index c3f3ae5de921..ebcb744708de 100644
--- a/llvm/include/llvm/MC/MCObjectStreamer.h
+++ b/llvm/include/llvm/MC/MCObjectStreamer.h
@@ -148,7 +148,7 @@ public:
   void emitDwarfAdvanceLineAddr(int64_t LineDelta, const MCSymbol *LastLabel,
                                 const MCSymbol *Label, unsigned PointerSize);
   void emitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
-                                 const MCSymbol *Label);
+                                 const MCSymbol *Label) override;
   void emitCVLocDirective(unsigned FunctionId, unsigned FileNo, unsigned Line,
                           unsigned Column, bool PrologueEnd, bool IsStmt,
                           StringRef FileName, SMLoc Loc) override;
diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index 484c62538366..f4d3e993745a 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -930,6 +930,9 @@ public:
       ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
       codeview::DefRangeFramePointerRelHeader DRHdr);
 
+  virtual void emitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
+                                         const MCSymbol *Label) {}
+
   /// This implements the CodeView '.cv_stringtable' assembler directive.
   virtual void emitCVStringTableDirective() {}
 
diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index 6a8572e57922..5485fe6349e3 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -158,6 +158,8 @@ public:
   void emitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
   void emitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override;
   bool emitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
+  void emitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
+                                 const MCSymbol *Label) override;
 
   void emitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override;
   void BeginCOFFSymbolDef(const MCSymbol *Symbol) override;
@@ -633,6 +635,36 @@ void MCAsmStreamer::emitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
   EmitEOL();
 }
 
+static const MCExpr *buildSymbolDiff(MCContext &Context,
+                                     const MCSymbol *A,
+                                     const MCSymbol *B) {
+  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+  const MCExpr *ARef = MCSymbolRefExpr::create(A, Variant, Context);
+  const MCExpr *BRef = MCSymbolRefExpr::create(B, Variant, Context);
+  const MCExpr *AddrDelta =
+      MCBinaryExpr::create(MCBinaryExpr::Sub, ARef, BRef, Context);
+  return AddrDelta;
+}
+
+static const MCExpr *forceExpAbs(MCStreamer &Streamer, const MCExpr* Expr) {
+  MCContext &Context = Streamer.getContext();
+  assert(!isa<MCSymbolRefExpr>(Expr));
+  if (Context.getAsmInfo()->hasAggressiveSymbolFolding())
+    return Expr;
+
+   MCSymbol *ABS = Context.createTempSymbol();
+   Streamer.emitAssignment(ABS, Expr);
+   return MCSymbolRefExpr::create(ABS, Context);
+ }
+
+void MCAsmStreamer::emitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
+                                              const MCSymbol *Label) {
+  emitIntValue(dwarf::DW_CFA_advance_loc4, 1);
+  const MCExpr *AddrDelta = buildSymbolDiff(getContext(), Label, LastLabel);
+  AddrDelta = forceExpAbs(*this, AddrDelta);
+  emitValue(AddrDelta, 4);
+}
+
 bool MCAsmStreamer::emitSymbolAttribute(MCSymbol *Symbol,
                                         MCSymbolAttr Attribute) {
   switch (Attribute) {