Add support for subsections to the ELF assembler. Fixes PR8717.
Differential Revision: http://llvm-reviews.chandlerc.com/D598
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179725 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index 8970e18..fb5ab28 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -214,7 +214,8 @@
MCFragment::MCFragment(FragmentType _Kind, MCSectionData *_Parent)
: Kind(_Kind), Parent(_Parent), Atom(0), Offset(~UINT64_C(0))
{
- Parent->getFragmentList().push_back(this);
+ if (Parent)
+ Parent->getFragmentList().push_back(this);
}
/* *** */
@@ -242,6 +243,36 @@
A->getSectionList().push_back(this);
}
+MCSectionData::iterator
+MCSectionData::getSubsectionInsertionPoint(unsigned Subsection) {
+ if (Subsection == 0 && SubsectionFragmentMap.empty())
+ return end();
+
+ SmallVectorImpl<std::pair<unsigned, MCFragment *> >::iterator MI =
+ std::lower_bound(SubsectionFragmentMap.begin(), SubsectionFragmentMap.end(),
+ std::make_pair(Subsection, (MCFragment *)0));
+ bool ExactMatch = false;
+ if (MI != SubsectionFragmentMap.end()) {
+ ExactMatch = MI->first == Subsection;
+ if (ExactMatch)
+ ++MI;
+ }
+ iterator IP;
+ if (MI == SubsectionFragmentMap.end())
+ IP = end();
+ else
+ IP = MI->second;
+ if (!ExactMatch && Subsection != 0) {
+ // The GNU as documentation claims that subsections have an alignment of 4,
+ // although this appears not to be the case.
+ MCFragment *F = new MCDataFragment();
+ SubsectionFragmentMap.insert(MI, std::make_pair(Subsection, F));
+ getFragmentList().insert(IP, F);
+ F->setParent(this);
+ }
+ return IP;
+}
+
/* *** */
MCSymbolData::MCSymbolData() : Symbol(0) {}