Simplify MCFillFragment.

The value size was always 1 or 0, so we don't need to store it.

In a no asserts build this takes the testcase of pr26208 from 11 to 10
seconds.

llvm-svn: 258141

llvm/include/llvm/MC/MCFragment.h

@@ -321,36 +321,19 @@ public:
 
 class MCFillFragment : public MCFragment {
 
-  /// Value - Value to use for filling bytes.
-  int64_t Value;
+  /// Value to use for filling bytes.
+  uint8_t Value;
 
-  /// ValueSize - The size (in bytes) of \p Value to use when filling, or 0 if
-  /// this is a virtual fill fragment.
-  unsigned ValueSize;
-
-  /// Size - The number of bytes to insert.
+  /// The number of bytes to insert.
   uint64_t Size;
 
 public:
-  MCFillFragment(int64_t Value, unsigned ValueSize, uint64_t Size,
-                 MCSection *Sec = nullptr)
-      : MCFragment(FT_Fill, false, 0, Sec), Value(Value), ValueSize(ValueSize),
-        Size(Size) {
-    assert((!ValueSize || (Size % ValueSize) == 0) &&
-           "Fill size must be a multiple of the value size!");
-  }
-
-  /// \name Accessors
-  /// @{
-
-  int64_t getValue() const { return Value; }
-
-  unsigned getValueSize() const { return ValueSize; }
+  MCFillFragment(uint8_t Value, uint64_t Size, MCSection *Sec = nullptr)
+      : MCFragment(FT_Fill, false, 0, Sec), Value(Value), Size(Size) {}
 
+  uint8_t getValue() const { return Value; }
   uint64_t getSize() const { return Size; }
 
-  /// @}
-
   static bool classof(const MCFragment *F) {
     return F->getKind() == MCFragment::FT_Fill;
   }

llvm/lib/MC/MCAssembler.cpp

@@ -489,17 +489,8 @@ static void writeFragment(const MCAssembler &Asm, const MCAsmLayout &Layout,
     ++stats::EmittedFillFragments;
     const MCFillFragment &FF = cast<MCFillFragment>(F);
 
-    assert(FF.getValueSize() && "Invalid virtual align in concrete fragment!");
-
-    for (uint64_t i = 0, e = FF.getSize() / FF.getValueSize(); i != e; ++i) {
-      switch (FF.getValueSize()) {
-      default: llvm_unreachable("Invalid size!");
-      case 1: OW->write8 (uint8_t (FF.getValue())); break;
-      case 2: OW->write16(uint16_t(FF.getValue())); break;
-      case 4: OW->write32(uint32_t(FF.getValue())); break;
-      case 8: OW->write64(uint64_t(FF.getValue())); break;
-      }
-    }
+    for (uint64_t I = 0, E = FF.getSize(); I != E; ++I)
+      OW->write8(FF.getValue());
     break;
   }
 
@@ -578,8 +569,7 @@ void MCAssembler::writeSectionData(const MCSection *Sec,
                "Invalid align in virtual section!");
         break;
       case MCFragment::FT_Fill:
-        assert((cast<MCFillFragment>(F).getValueSize() == 0 ||
-                cast<MCFillFragment>(F).getValue() == 0) &&
+        assert((cast<MCFillFragment>(F).getValue() == 0) &&
                "Invalid fill in virtual section!");
         break;
       }

llvm/lib/MC/MCFragment.cpp

@@ -386,8 +386,7 @@ void MCFragment::dump() {
   }
   case MCFragment::FT_Fill:  {
     const MCFillFragment *FF = cast<MCFillFragment>(this);
-    OS << " Value:" << FF->getValue() << " ValueSize:" << FF->getValueSize()
-       << " Size:" << FF->getSize();
+    OS << " Value:" << FF->getValue() << " Size:" << FF->getSize();
     break;
   }
   case MCFragment::FT_Relaxable:  {

llvm/lib/MC/MCMachOStreamer.cpp

@@ -414,7 +414,7 @@ void MCMachOStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
   if (ByteAlignment != 1)
     new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, Section);
 
-  MCFragment *F = new MCFillFragment(0, 0, Size, Section);
+  MCFragment *F = new MCFillFragment(0, Size, Section);
   Symbol->setFragment(F);
 
   // Update the maximum alignment on the zero fill section if necessary.

llvm/lib/MC/MCObjectStreamer.cpp

@@ -436,9 +436,9 @@ bool MCObjectStreamer::EmitRelocDirective(const MCExpr &Offset, StringRef Name,
 
 void MCObjectStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
   const MCSection *Sec = getCurrentSection().first;
+  (void)Sec;
   assert(Sec && "need a section");
-  unsigned ItemSize = Sec->isVirtualSection() ? 0 : 1;
-  insert(new MCFillFragment(FillValue, ItemSize, NumBytes));
+  insert(new MCFillFragment(FillValue, NumBytes));
 }
 
 void MCObjectStreamer::FinishImpl() {

llvm/lib/MC/WinCOFFStreamer.cpp

@@ -258,7 +258,7 @@ void MCWinCOFFStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                         ByteAlignment, Section);
 
   MCFillFragment *Fragment = new MCFillFragment(
-      /*Value=*/0, /*ValueSize=*/0, Size, Section);
+      /*Value=*/0, Size, Section);
   Symbol->setFragment(Fragment);
 }