[MC] Export llvm::WinCOFFObjectWriter and access it from MCWinCOFFStr…

…eamer Similar to commit 28fcafb (2011) for MachObjectWriter. MCWinCOFFStreamer can now access WinCOFFObjectWriter directly without holding object file format specific inforamtion in MCAssembler (e.g. IncrementalLinkerCompatible).
gbaraldi · Jul 21, 2024 · 9539a77 · 9539a77
1 parent 6db2465
commit 9539a77
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Showing 7 changed files with 57 additions and 51 deletions.
diff --git a/llvm/include/llvm/MC/MCAssembler.h b/llvm/include/llvm/MC/MCAssembler.h
@@ -84,7 +84,6 @@ class MCAssembler {
   bool HasLayout = false;
   bool RelaxAll = false;
   bool SubsectionsViaSymbols = false;
-  bool IncrementalLinkerCompatible = false;
 
   SectionListType Sections;
 
@@ -298,13 +297,6 @@ class MCAssembler {
   bool getSubsectionsViaSymbols() const { return SubsectionsViaSymbols; }
   void setSubsectionsViaSymbols(bool Value) { SubsectionsViaSymbols = Value; }
 
-  bool isIncrementalLinkerCompatible() const {
-    return IncrementalLinkerCompatible;
-  }
-  void setIncrementalLinkerCompatible(bool Value) {
-    IncrementalLinkerCompatible = Value;
-  }
-
   bool hasLayout() const { return HasLayout; }
   bool getRelaxAll() const { return RelaxAll; }
   void setRelaxAll(bool Value) { RelaxAll = Value; }

diff --git a/llvm/include/llvm/MC/MCWinCOFFObjectWriter.h b/llvm/include/llvm/MC/MCWinCOFFObjectWriter.h
@@ -43,6 +43,37 @@ class MCWinCOFFObjectTargetWriter : public MCObjectTargetWriter {
   virtual bool recordRelocation(const MCFixup &) const { return true; }
 };
 
+class WinCOFFWriter;
+
+class WinCOFFObjectWriter : public MCObjectWriter {
+  friend class WinCOFFWriter;
+
+  std::unique_ptr<MCWinCOFFObjectTargetWriter> TargetObjectWriter;
+  std::unique_ptr<WinCOFFWriter> ObjWriter, DwoWriter;
+  bool IncrementalLinkerCompatible = false;
+
+public:
+  WinCOFFObjectWriter(std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW,
+                      raw_pwrite_stream &OS);
+  WinCOFFObjectWriter(std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW,
+                      raw_pwrite_stream &OS, raw_pwrite_stream &DwoOS);
+
+  // MCObjectWriter interface implementation.
+  void reset() override;
+  void setIncrementalLinkerCompatible(bool Value) {
+    IncrementalLinkerCompatible = Value;
+  }
+  void executePostLayoutBinding(MCAssembler &Asm) override;
+  bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
+                                              const MCSymbol &SymA,
+                                              const MCFragment &FB, bool InSet,
+                                              bool IsPCRel) const override;
+  void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment,
+                        const MCFixup &Fixup, MCValue Target,
+                        uint64_t &FixedValue) override;
+  uint64_t writeObject(MCAssembler &Asm) override;
+};
+
 /// Construct a new Win COFF writer instance.
 ///
 /// \param MOTW - The target specific WinCOFF writer subclass.

diff --git a/llvm/include/llvm/MC/MCWinCOFFStreamer.h b/llvm/include/llvm/MC/MCWinCOFFStreamer.h
@@ -22,6 +22,7 @@ class MCSection;
 class MCSubtargetInfo;
 class MCSymbol;
 class StringRef;
+class WinCOFFObjectWriter;
 class raw_pwrite_stream;
 
 class MCWinCOFFStreamer : public MCObjectStreamer {
@@ -36,6 +37,8 @@ class MCWinCOFFStreamer : public MCObjectStreamer {
     MCObjectStreamer::reset();
   }
 
+  WinCOFFObjectWriter &getWriter();
+
   /// \name MCStreamer interface
   /// \{
 

diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
@@ -94,7 +94,6 @@ MCAssembler::~MCAssembler() = default;
 void MCAssembler::reset() {
   RelaxAll = false;
   SubsectionsViaSymbols = false;
-  IncrementalLinkerCompatible = false;
   Sections.clear();
   Symbols.clear();
   LinkerOptions.clear();

diff --git a/llvm/lib/MC/MCWinCOFFStreamer.cpp b/llvm/lib/MC/MCWinCOFFStreamer.cpp
@@ -28,6 +28,7 @@
 #include "llvm/MC/MCSectionCOFF.h"
 #include "llvm/MC/MCSymbolCOFF.h"
 #include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/MCWinCOFFObjectWriter.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MathExtras.h"
@@ -49,7 +50,11 @@ MCWinCOFFStreamer::MCWinCOFFStreamer(MCContext &Context,
       CurSymbol(nullptr) {
   auto *TO = Context.getTargetOptions();
   if (TO && TO->MCIncrementalLinkerCompatible)
-    getAssembler().setIncrementalLinkerCompatible(true);
+    getWriter().setIncrementalLinkerCompatible(true);
+}
+
+WinCOFFObjectWriter &MCWinCOFFStreamer::getWriter() {
+  return static_cast<WinCOFFObjectWriter &>(getAssembler().getWriter());
 }
 
 void MCWinCOFFStreamer::emitInstToData(const MCInst &Inst,

diff --git a/llvm/lib/MC/WinCOFFObjectWriter.cpp b/llvm/lib/MC/WinCOFFObjectWriter.cpp
@@ -119,10 +119,9 @@ class COFFSection {
 
   SmallVector<COFFSymbol *, 1> OffsetSymbols;
 };
+} // namespace
 
-class WinCOFFObjectWriter;
-
-class WinCOFFWriter {
+class llvm::WinCOFFWriter {
   WinCOFFObjectWriter &OWriter;
   support::endian::Writer W;
 
@@ -196,41 +195,19 @@ class WinCOFFWriter {
   void assignFileOffsets(MCAssembler &Asm);
 };
 
-class WinCOFFObjectWriter : public MCObjectWriter {
-  friend class WinCOFFWriter;
-
-  std::unique_ptr<MCWinCOFFObjectTargetWriter> TargetObjectWriter;
-  std::unique_ptr<WinCOFFWriter> ObjWriter, DwoWriter;
-
-public:
-  WinCOFFObjectWriter(std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW,
-                      raw_pwrite_stream &OS)
-      : TargetObjectWriter(std::move(MOTW)),
-        ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
-                                                  WinCOFFWriter::AllSections)) {
-  }
-  WinCOFFObjectWriter(std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW,
-                      raw_pwrite_stream &OS, raw_pwrite_stream &DwoOS)
-      : TargetObjectWriter(std::move(MOTW)),
-        ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
-                                                  WinCOFFWriter::NonDwoOnly)),
-        DwoWriter(std::make_unique<WinCOFFWriter>(*this, DwoOS,
-                                                  WinCOFFWriter::DwoOnly)) {}
-
-  // MCObjectWriter interface implementation.
-  void reset() override;
-  void executePostLayoutBinding(MCAssembler &Asm) override;
-  bool isSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
-                                              const MCSymbol &SymA,
-                                              const MCFragment &FB, bool InSet,
-                                              bool IsPCRel) const override;
-  void recordRelocation(MCAssembler &Asm, const MCFragment *Fragment,
-                        const MCFixup &Fixup, MCValue Target,
-                        uint64_t &FixedValue) override;
-  uint64_t writeObject(MCAssembler &Asm) override;
-};
-
-} // end anonymous namespace
+WinCOFFObjectWriter::WinCOFFObjectWriter(
+    std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS)
+    : TargetObjectWriter(std::move(MOTW)),
+      ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
+                                                WinCOFFWriter::AllSections)) {}
+WinCOFFObjectWriter::WinCOFFObjectWriter(
+    std::unique_ptr<MCWinCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS,
+    raw_pwrite_stream &DwoOS)
+    : TargetObjectWriter(std::move(MOTW)),
+      ObjWriter(std::make_unique<WinCOFFWriter>(*this, OS,
+                                                WinCOFFWriter::NonDwoOnly)),
+      DwoWriter(std::make_unique<WinCOFFWriter>(*this, DwoOS,
+                                                WinCOFFWriter::DwoOnly)) {}
 
 static bool isDwoSection(const MCSection &Sec) {
   return Sec.getName().ends_with(".dwo");
@@ -1125,7 +1102,7 @@ uint64_t WinCOFFWriter::writeObject(MCAssembler &Asm) {
 
   // MS LINK expects to be able to use this timestamp to implement their
   // /INCREMENTAL feature.
-  if (Asm.isIncrementalLinkerCompatible()) {
+  if (OWriter.IncrementalLinkerCompatible) {
     Header.TimeDateStamp = getTime();
   } else {
     // Have deterministic output if /INCREMENTAL isn't needed. Also matches GNU.
@@ -1174,6 +1151,7 @@ uint64_t WinCOFFWriter::writeObject(MCAssembler &Asm) {
 // MCObjectWriter interface implementations
 
 void WinCOFFObjectWriter::reset() {
+  IncrementalLinkerCompatible = false;
   ObjWriter->reset();
   if (DwoWriter)
     DwoWriter->reset();

diff --git a/llvm/lib/MC/XCOFFObjectWriter.cpp b/llvm/lib/MC/XCOFFObjectWriter.cpp
@@ -825,8 +825,6 @@ uint64_t XCOFFObjectWriter::writeObject(MCAssembler &Asm) {
   // We always emit a timestamp of 0 for reproducibility, so ensure incremental
   // linking is not enabled, in case, like with Windows COFF, such a timestamp
   // is incompatible with incremental linking of XCOFF.
-  if (Asm.isIncrementalLinkerCompatible())
-    report_fatal_error("Incremental linking not supported for XCOFF.");
 
   finalizeSectionInfo();
   uint64_t StartOffset = W.OS.tell();