Revert "[llvm-objcopy] Add support for nested and overlapping segments"
This reverts commit r313656. Appears to be broken on Windows.
llvm-svn: 313664
diff --git a/llvm/tools/llvm-objcopy/Object.cpp b/llvm/tools/llvm-objcopy/Object.cpp
index 28323f4..0d16e69 100644
--- a/llvm/tools/llvm-objcopy/Object.cpp
+++ b/llvm/tools/llvm-objcopy/Object.cpp
@@ -246,15 +246,6 @@
Segment.Offset + Segment.FileSize >= Section.OriginalOffset + SecSize;
}
-// Returns true IFF a segment's original offset is inside of another segment's
-// range.
-static bool segmentOverlapsSegment(const Segment &Child,
- const Segment &Parent) {
-
- return Parent.OriginalOffset <= Child.OriginalOffset &&
- Parent.OriginalOffset + Parent.FileSize > Child.OriginalOffset;
-}
-
template <class ELFT>
void Object<ELFT>::readProgramHeaders(const ELFFile<ELFT> &ElfFile) {
uint32_t Index = 0;
@@ -283,30 +274,6 @@
}
}
}
- // Now we do an O(n^2) loop through the segments in order to match up
- // segments.
- for (auto &Child : Segments) {
- for (auto &Parent : Segments) {
- // Every segment will overlap with itself but we don't want a segment to
- // be it's own parent so we avoid that situation.
- if (&Child != &Parent && segmentOverlapsSegment(*Child, *Parent)) {
- // We want a canonical "most parental" segment but this requires
- // inspecting the ParentSegment.
- if (Child->ParentSegment != nullptr) {
- if (Child->ParentSegment->OriginalOffset > Parent->OriginalOffset) {
- Child->ParentSegment = Parent.get();
- } else if (Child->ParentSegment->Index > Parent->Index) {
- // They must have equal OriginalOffsets so we need to disambiguate.
- // To decide which is the parent we'll choose the one with the
- // higher index.
- Child->ParentSegment = Parent.get();
- }
- } else {
- Child->ParentSegment = Parent.get();
- }
- }
- }
- }
}
template <class ELFT>
@@ -579,30 +546,13 @@
}
template <class ELFT> void ELFObject<ELFT>::assignOffsets() {
- // We need a temporary list of segments that has a special order to it
- // so that we know that anytime ->ParentSegment is set that segment has
- // already had it's offset properly set.
- std::vector<Segment *> OrderedSegments;
- for (auto &Segment : this->Segments)
- OrderedSegments.push_back(Segment.get());
- auto CompareSegments = [](const Segment *A, const Segment *B) {
- // Any segment without a parent segment should come before a segment
- // that has a parent segment.
- if (A->OriginalOffset < B->OriginalOffset)
- return true;
- if (A->OriginalOffset > B->OriginalOffset)
- return false;
- return A->Index < B->Index;
- };
- std::stable_sort(std::begin(OrderedSegments), std::end(OrderedSegments),
- CompareSegments);
// The size of ELF + program headers will not change so it is ok to assume
// that the first offset of the first segment is a good place to start
// outputting sections. This covers both the standard case and the PT_PHDR
// case.
uint64_t Offset;
- if (!OrderedSegments.empty()) {
- Offset = OrderedSegments[0]->Offset;
+ if (!this->Segments.empty()) {
+ Offset = this->Segments[0]->Offset;
} else {
Offset = sizeof(Elf_Ehdr);
}
@@ -611,20 +561,10 @@
// then it's acceptable, but not ideal, to simply move it to after the
// segments. So we can simply layout segments one after the other accounting
// for alignment.
- for (auto &Segment : OrderedSegments) {
- // We assume that segments have been ordered by OriginalOffset and Index
- // such that a parent segment will always come before a child segment in
- // OrderedSegments. This means that the Offset of the ParentSegment should
- // already be set and we can set our offset relative to it.
- if (Segment->ParentSegment != nullptr) {
- auto Parent = Segment->ParentSegment;
- Segment->Offset =
- Parent->Offset + Segment->OriginalOffset - Parent->OriginalOffset;
- } else {
- Offset = alignTo(Offset, Segment->Align == 0 ? 1 : Segment->Align);
- Segment->Offset = Offset;
- Offset += Segment->FileSize;
- }
+ for (auto &Segment : this->Segments) {
+ Offset = alignTo(Offset, Segment->Align);
+ Segment->Offset = Offset;
+ Offset += Segment->FileSize;
}
// Now the offset of every segment has been set we can assign the offsets
// of each section. For sections that are covered by a segment we should use