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

4 files changed, 19 insertions, 21 deletions

diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.h b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.h
index 1c840d998e0..ca72ccf0f76 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.h
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCExpr.h
@@ -82,7 +82,7 @@ public:
                                  const MCAsmLayout *Layout,
                                  const MCFixup *Fixup) const override;
   void visitUsedExpr(MCStreamer &Streamer) const override;
-  const MCSection *FindAssociatedSection() const override {
+  MCSection *FindAssociatedSection() const override {
     return getSubExpr()->FindAssociatedSection();
   }
 
diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
index 4fd96145fb2..4f1c3c73e71 100644
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1054,7 +1054,7 @@ void PPCLinuxAsmPrinter::EmitFunctionEntryLabel() {
 
   // Emit an official procedure descriptor.
   MCSectionSubPair Current = OutStreamer->getCurrentSection();
-  const MCSectionELF *Section = OutStreamer->getContext().getELFSection(
+  MCSectionELF *Section = OutStreamer->getContext().getELFSection(
       ".opd", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
   OutStreamer->SwitchSection(Section);
   OutStreamer->EmitLabel(CurrentFnSym);
@@ -1084,8 +1084,8 @@ bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
       static_cast<PPCTargetStreamer &>(*OutStreamer->getTargetStreamer());
 
   if (!TOC.empty()) {
-    const MCSectionELF *Section;
-    
+    MCSectionELF *Section;
+
     if (isPPC64)
       Section = OutStreamer->getContext().getELFSection(
           ".toc", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
@@ -1285,15 +1285,14 @@ EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs) {
     static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
 
   // .lazy_symbol_pointer
-  const MCSection *LSPSection = TLOFMacho.getLazySymbolPointerSection();
-  
+  MCSection *LSPSection = TLOFMacho.getLazySymbolPointerSection();
+
   // Output stubs for dynamically-linked functions
   if (TM.getRelocationModel() == Reloc::PIC_) {
-    const MCSection *StubSection = 
-    OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
-                               MachO::S_SYMBOL_STUBS |
-                               MachO::S_ATTR_PURE_INSTRUCTIONS,
-                               32, SectionKind::getText());
+    MCSection *StubSection = OutContext.getMachOSection(
+        "__TEXT", "__picsymbolstub1",
+        MachO::S_SYMBOL_STUBS | MachO::S_ATTR_PURE_INSTRUCTIONS, 32,
+        SectionKind::getText());
     for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
       OutStreamer->SwitchSection(StubSection);
       EmitAlignment(4);
@@ -1356,12 +1355,11 @@ EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs) {
     OutStreamer->AddBlankLine();
     return;
   }
-  
-  const MCSection *StubSection =
-    OutContext.getMachOSection("__TEXT","__symbol_stub1",
-                               MachO::S_SYMBOL_STUBS |
-                               MachO::S_ATTR_PURE_INSTRUCTIONS,
-                               16, SectionKind::getText());
+
+  MCSection *StubSection = OutContext.getMachOSection(
+      "__TEXT", "__symbol_stub1",
+      MachO::S_SYMBOL_STUBS | MachO::S_ATTR_PURE_INSTRUCTIONS, 16,
+      SectionKind::getText());
   for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
     MCSymbol *Stub = Stubs[i].first;
     MCSymbol *RawSym = Stubs[i].second.getPointer();
diff --git a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
index 2903cc192aa..9ad13407008 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
@@ -22,7 +22,7 @@ Initialize(MCContext &Ctx, const TargetMachine &TM) {
   InitializeELF(TM.Options.UseInitArray);
 }
 
-const MCSection *PPC64LinuxTargetObjectFile::SelectSectionForGlobal(
+MCSection *PPC64LinuxTargetObjectFile::SelectSectionForGlobal(
     const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
     const TargetMachine &TM) const {
   // Here override ReadOnlySection to DataRelROSection for PPC64 SVR4 ABI
diff --git a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
index cd84da22275..d248791f2ca 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
+++ b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
@@ -22,9 +22,9 @@ namespace llvm {
 
     void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
 
-    const MCSection *SelectSectionForGlobal(const GlobalValue *GV,
-                                        SectionKind Kind, Mangler &Mang,
-                                        const TargetMachine &TM) const override;
+    MCSection *SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                                      Mangler &Mang,
+                                      const TargetMachine &TM) const override;
 
     /// \brief Describe a TLS variable address within debug info.
     const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const override;