Move alignment from MCSectionData to MCSection.

This starts merging MCSection and MCSectionData.

There are a few issues with the current split between MCSection and
MCSectionData.

* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.

* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.

* It makes it harder to remember where each item is.

The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.

Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.

llvm-svn: 237936

1 files changed, 3 insertions, 4 deletions

diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
index 2f5559a16b2..71cc516237f 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -275,7 +275,7 @@ private:
   unsigned EmittedArch;
   SmallVector<AttributeItem, 64> Contents;
 
-  const MCSection *AttributeSection;
+  MCSection *AttributeSection;
 
   AttributeItem *getAttributeItem(unsigned Attribute) {
     for (size_t i = 0; i < Contents.size(); ++i)
@@ -431,8 +431,7 @@ public:
   void emitRegSave(const SmallVectorImpl<unsigned> &RegList, bool isVector);
   void emitUnwindRaw(int64_t Offset, const SmallVectorImpl<uint8_t> &Opcodes);
 
-  void ChangeSection(const MCSection *Section,
-                     const MCExpr *Subsection) override {
+  void ChangeSection(MCSection *Section, const MCExpr *Subsection) override {
     // We have to keep track of the mapping symbol state of any sections we
     // use. Each one should start off as EMS_None, which is provided as the
     // default constructor by DenseMap::lookup.
@@ -1028,7 +1027,7 @@ inline void ARMELFStreamer::SwitchToEHSection(const char *Prefix,
   const MCSymbol *Group = FnSection.getGroup();
   if (Group)
     Flags |= ELF::SHF_GROUP;
-  const MCSectionELF *EHSection =
+  MCSectionELF *EHSection =
       getContext().getELFSection(EHSecName, Type, Flags, 0, Group,
                                  FnSection.getUniqueID(), nullptr, &FnSection);