MC: Have the object writers return the number of bytes written. NFCI.

This removes the last external use of the stream.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47042

llvm-svn: 332863

5 files changed, 27 insertions, 17 deletions

diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index e5014e64043..9826996c571 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -247,7 +247,7 @@ public:
                                               const MCFragment &FB, bool InSet,
                                               bool IsPCRel) const override;
 
-  void writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
+  uint64_t writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
   void writeSection(const SectionIndexMapTy &SectionIndexMap,
                     uint32_t GroupSymbolIndex, uint64_t Offset, uint64_t Size,
                     const MCSectionELF &Section);
@@ -1205,8 +1205,10 @@ void ELFObjectWriter::writeSectionHeader(
   }
 }
 
-void ELFObjectWriter::writeObject(MCAssembler &Asm,
-                                  const MCAsmLayout &Layout) {
+uint64_t ELFObjectWriter::writeObject(MCAssembler &Asm,
+                                      const MCAsmLayout &Layout) {
+  uint64_t StartOffset = W.OS.tell();
+
   MCContext &Ctx = Asm.getContext();
   MCSectionELF *StrtabSection =
       Ctx.getELFSection(".strtab", ELF::SHT_STRTAB, 0);
@@ -1334,6 +1336,8 @@ void ELFObjectWriter::writeObject(MCAssembler &Asm,
   }
   Stream.pwrite(reinterpret_cast<char *>(&NumSections), sizeof(NumSections),
                 NumSectionsOffset);
+
+  return W.OS.tell() - StartOffset;
 }
 
 bool ELFObjectWriter::isSymbolRefDifferenceFullyResolvedImpl(
diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
index f72c3fda8f0..f63df8b1002 100644
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -815,13 +815,8 @@ void MCAssembler::Finish() {
   MCAsmLayout Layout(*this);
   layout(Layout);
 
-  raw_ostream &OS = getWriter().getStream();
-  uint64_t StartOffset = OS.tell();
-
   // Write the object file.
-  getWriter().writeObject(*this, Layout);
-
-  stats::ObjectBytes += OS.tell() - StartOffset;
+  stats::ObjectBytes += getWriter().writeObject(*this, Layout);
 }
 
 bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup,
diff --git a/llvm/lib/MC/MachObjectWriter.cpp b/llvm/lib/MC/MachObjectWriter.cpp
index ba8922c8997..a464af1d42a 100644
--- a/llvm/lib/MC/MachObjectWriter.cpp
+++ b/llvm/lib/MC/MachObjectWriter.cpp
@@ -735,8 +735,10 @@ static MachO::LoadCommandType getLCFromMCVM(MCVersionMinType Type) {
   llvm_unreachable("Invalid mc version min type");
 }
 
-void MachObjectWriter::writeObject(MCAssembler &Asm,
-                                   const MCAsmLayout &Layout) {
+uint64_t MachObjectWriter::writeObject(MCAssembler &Asm,
+                                       const MCAsmLayout &Layout) {
+  uint64_t StartOffset = W.OS.tell();
+
   // Compute symbol table information and bind symbol indices.
   computeSymbolTable(Asm, LocalSymbolData, ExternalSymbolData,
                      UndefinedSymbolData);
@@ -1011,6 +1013,8 @@ void MachObjectWriter::writeObject(MCAssembler &Asm,
     // Write the string table.
     StringTable.write(W.OS);
   }
+
+  return W.OS.tell() - StartOffset;
 }
 
 std::unique_ptr<MCObjectWriter>
diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp
index cbb12cab71e..f3ff3b9c284 100644
--- a/llvm/lib/MC/WasmObjectWriter.cpp
+++ b/llvm/lib/MC/WasmObjectWriter.cpp
@@ -285,7 +285,7 @@ private:
   void executePostLayoutBinding(MCAssembler &Asm,
                                 const MCAsmLayout &Layout) override;
 
-  void writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
+  uint64_t writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
 
   void writeString(const StringRef Str) {
     encodeULEB128(Str.size(), W.OS);
@@ -1075,8 +1075,10 @@ static bool isInSymtab(const MCSymbolWasm &Sym) {
   return true;
 }
 
-void WasmObjectWriter::writeObject(MCAssembler &Asm,
-                                   const MCAsmLayout &Layout) {
+uint64_t WasmObjectWriter::writeObject(MCAssembler &Asm,
+                                       const MCAsmLayout &Layout) {
+  uint64_t StartOffset = W.OS.tell();
+
   LLVM_DEBUG(dbgs() << "WasmObjectWriter::writeObject\n");
   MCContext &Ctx = Asm.getContext();
 
@@ -1472,6 +1474,7 @@ void WasmObjectWriter::writeObject(MCAssembler &Asm,
   writeCustomRelocSections();
 
   // TODO: Translate the .comment section to the output.
+  return W.OS.tell() - StartOffset;
 }
 
 std::unique_ptr<MCObjectWriter>
diff --git a/llvm/lib/MC/WinCOFFObjectWriter.cpp b/llvm/lib/MC/WinCOFFObjectWriter.cpp
index c87bc02fe05..f78f04ca7d3 100644
--- a/llvm/lib/MC/WinCOFFObjectWriter.cpp
+++ b/llvm/lib/MC/WinCOFFObjectWriter.cpp
@@ -206,7 +206,7 @@ public:
   void assignSectionNumbers();
   void assignFileOffsets(MCAssembler &Asm, const MCAsmLayout &Layout);
 
-  void writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
+  uint64_t writeObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
 };
 
 } // end anonymous namespace
@@ -963,8 +963,10 @@ void WinCOFFObjectWriter::assignFileOffsets(MCAssembler &Asm,
   Header.PointerToSymbolTable = Offset;
 }
 
-void WinCOFFObjectWriter::writeObject(MCAssembler &Asm,
-                                      const MCAsmLayout &Layout) {
+uint64_t WinCOFFObjectWriter::writeObject(MCAssembler &Asm,
+                                          const MCAsmLayout &Layout) {
+  uint64_t StartOffset = W.OS.tell();
+
   if (Sections.size() > INT32_MAX)
     report_fatal_error(
         "PE COFF object files can't have more than 2147483647 sections");
@@ -1070,6 +1072,8 @@ void WinCOFFObjectWriter::writeObject(MCAssembler &Asm,
 
   // Write a string table, which completes the entire COFF file.
   Strings.write(W.OS);
+
+  return W.OS.tell() - StartOffset;
 }
 
 MCWinCOFFObjectTargetWriter::MCWinCOFFObjectTargetWriter(unsigned Machine_)