[ELF] Add CodeModel attribute to the DefinedAtom class

MIPS ELF symbols might contain some additional MIPS-specific flags
in the st_other field besides visibility ones. These flags indicate
code properties like microMIPS / MIPS16 encoding, position independent
code etc. We need to transfer the flags from input objects to the
output linked file to write them into the symbol table, adjust symbols
addresses etc.

I add new attribute CodeModel to the DefinedAtom class to hold target
specific flag and to get over YAML/Native format conversion barrier.
Other architectures/targets can extend CodeModel enumeration by their
own flags.

MIPS specific part of this patch adds support for STO_MIPS_MICROMIPS
flag. This flag marks microMIPS symbols. Such symbol should:
a) Has STO_MIPS_MICROMIPS in the corresponding .symtab record.
b) Has adjusted (odd) address in the corresponding .symtab
   and .dynsym records.

llvm-svn: 221864

1 files changed, 14 insertions, 0 deletions

diff --git a/lld/lib/ReaderWriter/YAML/ReaderWriterYAML.cpp b/lld/lib/ReaderWriter/YAML/ReaderWriterYAML.cpp
index 6993ee4a099..5b83f5868be 100644
--- a/lld/lib/ReaderWriter/YAML/ReaderWriterYAML.cpp
+++ b/lld/lib/ReaderWriter/YAML/ReaderWriterYAML.cpp
@@ -386,6 +386,16 @@ template <> struct ScalarEnumerationTraits<lld::DefinedAtom::DynamicExport> {
   }
 };
 
+template <> struct ScalarEnumerationTraits<lld::DefinedAtom::CodeModel> {
+  static void enumeration(IO &io, lld::DefinedAtom::CodeModel &value) {
+    io.enumCase(value, "none", lld::DefinedAtom::codeNA);
+    io.enumCase(value, "mips-pic", lld::DefinedAtom::codeMipsPIC);
+    io.enumCase(value, "mips-micro", lld::DefinedAtom::codeMipsMicro);
+    io.enumCase(value, "mips-micro-pic", lld::DefinedAtom::codeMipsMicroPIC);
+    io.enumCase(value, "mips-16", lld::DefinedAtom::codeMips16);
+  }
+};
+
 template <>
 struct ScalarEnumerationTraits<lld::DefinedAtom::ContentPermissions> {
   static void enumeration(IO &io, lld::DefinedAtom::ContentPermissions &value) {
@@ -809,6 +819,7 @@ template <> struct MappingTraits<const lld::DefinedAtom *> {
           _alignment(atom->alignment()), _sectionChoice(atom->sectionChoice()),
           _sectionPosition(atom->sectionPosition()),
           _deadStrip(atom->deadStrip()), _dynamicExport(atom->dynamicExport()),
+          _codeModel(atom->codeModel()),
           _permissions(atom->permissions()), _size(atom->size()),
           _sectionName(atom->customSectionName()) {
       for (const lld::Reference *r : *atom)
@@ -859,6 +870,7 @@ template <> struct MappingTraits<const lld::DefinedAtom *> {
     SectionPosition sectionPosition() const override { return _sectionPosition; }
     DeadStripKind deadStrip() const override { return _deadStrip; }
     DynamicExport dynamicExport() const override { return _dynamicExport; }
+    CodeModel codeModel() const override { return _codeModel; }
     ContentPermissions permissions() const override { return _permissions; }
     void setGroupChild(bool val) { _isGroupChild = val; }
     bool isGroupChild() const { return _isGroupChild; }
@@ -904,6 +916,7 @@ template <> struct MappingTraits<const lld::DefinedAtom *> {
     SectionPosition                     _sectionPosition;
     DeadStripKind                       _deadStrip;
     DynamicExport                       _dynamicExport;
+    CodeModel                           _codeModel;
     ContentPermissions                  _permissions;
     uint32_t                            _ordinal;
     std::vector<ImplicitHex8>           _content;
@@ -951,6 +964,7 @@ template <> struct MappingTraits<const lld::DefinedAtom *> {
                                          DefinedAtom::deadStripNormal);
     io.mapOptional("dynamic-export",   keys->_dynamicExport,
                                          DefinedAtom::dynamicExportNormal);
+    io.mapOptional("code-model",       keys->_codeModel, DefinedAtom::codeNA);
     // default permissions based on content type
     io.mapOptional("permissions",      keys->_permissions,
                                          DefinedAtom::permissions(