Index: include/llvm/MC/MCContext.h
===================================================================
--- include/llvm/MC/MCContext.h
+++ include/llvm/MC/MCContext.h
@@ -385,8 +385,6 @@
const MCSymbolELF *Group,
const MCSectionELF *Associated);
- void renameELFSection(MCSectionELF *Section, StringRef Name);
-
MCSectionELF *createELFGroupSection(const MCSymbolELF *Group);
MCSectionCOFF *getCOFFSection(StringRef Section, unsigned Characteristics,
Index: include/llvm/MC/MCSectionELF.h
===================================================================
--- include/llvm/MC/MCSectionELF.h
+++ include/llvm/MC/MCSectionELF.h
@@ -35,9 +35,6 @@
/// This is the sh_type field of a section, drawn from the enums below.
unsigned Type;
- /// This is the sh_flags field of a section, drawn from the enums below.
- unsigned Flags;
-
unsigned UniqueID;
/// The size of each entry in this section. This size only makes sense for
@@ -62,8 +59,6 @@
Group->setIsSignature();
}
- void setSectionName(StringRef Name) { SectionName = Name; }
-
public:
~MCSectionELF();
@@ -73,7 +68,6 @@
StringRef getSectionName() const { return SectionName; }
unsigned getType() const { return Type; }
- unsigned getFlags() const { return Flags; }
unsigned getEntrySize() const { return EntrySize; }
const MCSymbolELF *getGroup() const { return Group; }
@@ -90,6 +84,9 @@
static bool classof(const MCSection *S) {
return S->getVariant() == SV_ELF;
}
+
+ /// This is the sh_flags field of a section, drawn from the enums below.
+ unsigned Flags;
};
} // end namespace llvm
Index: lib/MC/ELFObjectWriter.cpp
===================================================================
--- lib/MC/ELFObjectWriter.cpp
+++ lib/MC/ELFObjectWriter.cpp
@@ -573,8 +573,7 @@
// that it pointed to another string and subtracting 42 at runtime will
// produce the wrong value.
auto &Sec = cast<MCSectionELF>(Sym->getSection());
- unsigned Flags = Sec.getFlags();
- if (Flags & ELF::SHF_MERGE) {
+ if (Sec.Flags & ELF::SHF_MERGE) {
if (C != 0)
return true;
@@ -588,7 +587,7 @@
// are just an offset (@tpoff), require a symbol in gold versions before
// 5efeedf61e4fe720fd3e9a08e6c91c10abb66d42 (2014-09-26) which fixed
// http://sourceware.org/PR16773.
- if (Flags & ELF::SHF_TLS)
+ if (Sec.Flags & ELF::SHF_TLS)
return true;
// If the symbol is a thumb function the final relocation must set the lowest
@@ -969,7 +968,7 @@
EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rel) : sizeof(ELF::Elf32_Rel);
unsigned Flags = 0;
- if (Sec.getFlags() & ELF::SHF_GROUP)
+ if (Sec.Flags & ELF::SHF_GROUP)
Flags = ELF::SHF_GROUP;
MCSectionELF *RelaSection = Ctx.createELFRelSection(
@@ -979,26 +978,6 @@
return RelaSection;
}
-// Include the debug info compression header:
-// "ZLIB" followed by 8 bytes representing the uncompressed size of the section,
-// useful for consumers to preallocate a buffer to decompress into.
-static bool
-prependCompressionHeader(uint64_t Size,
- SmallVectorImpl<char> &CompressedContents) {
- const StringRef Magic = "ZLIB";
- if (Size <= Magic.size() + sizeof(Size) + CompressedContents.size())
- return false;
- if (sys::IsLittleEndianHost)
- sys::swapByteOrder(Size);
- CompressedContents.insert(CompressedContents.begin(),
- Magic.size() + sizeof(Size), 0);
- std::copy(Magic.begin(), Magic.end(), CompressedContents.begin());
- std::copy(reinterpret_cast<char *>(&Size),
- reinterpret_cast<char *>(&Size + 1),
- CompressedContents.begin() + Magic.size());
- return true;
-}
-
void ELFObjectWriter::writeSectionData(const MCAssembler &Asm, MCSection &Sec,
const MCAsmLayout &Layout) {
MCSectionELF &Section = static_cast<MCSectionELF &>(Sec);
@@ -1029,12 +1008,32 @@
return;
}
- if (!prependCompressionHeader(UncompressedData.size(), CompressedContents)) {
+ uint64_t HdrSize =
+ is64Bit() ? sizeof(ELF::Elf32_Chdr) : sizeof(ELF::Elf64_Chdr);
+ if (UncompressedData.size() <= HdrSize + CompressedContents.size()) {
getStream() << UncompressedData;
return;
}
- Asm.getContext().renameELFSection(&Section,
- (".z" + SectionName.drop_front(1)).str());
+
+ // Set the compressed flag. That is zlib style.
+ Section.Flags |= ELF::SHF_COMPRESSED;
+
+ // Platform specific header is followed by compressed data.
+ uint32_t Type = ELF::ELFCOMPRESS_ZLIB;
+ if (sys::IsLittleEndianHost)
+ sys::swapByteOrder(Type);
+
+ if (is64Bit()) {
+ // Write Elf64_Chdr header.
+ write((uint32_t)0); // ch_reserved field.
+ write((uint64_t)UncompressedData.size());
+ write((uint64_t)Sec.getAlignment());
+ } else {
+ // Write Elf32_Chdr header otherwise.
+ write((uint32_t)UncompressedData.size());
+ write((uint32_t)Sec.getAlignment());
+ }
+
getStream() << CompressedContents;
}
@@ -1152,9 +1151,8 @@
sh_link = SectionIndexMap.lookup(Section.getAssociatedSection());
WriteSecHdrEntry(StrTabBuilder.getOffset(Section.getSectionName()),
- Section.getType(), Section.getFlags(), 0, Offset, Size,
- sh_link, sh_info, Section.getAlignment(),
- Section.getEntrySize());
+ Section.getType(), Section.Flags, 0, Offset, Size, sh_link,
+ sh_info, Section.getAlignment(), Section.getEntrySize());
}
void ELFObjectWriter::writeSectionHeader(
Index: lib/MC/MCContext.cpp
===================================================================
--- lib/MC/MCContext.cpp
+++ lib/MC/MCContext.cpp
@@ -285,22 +285,6 @@
Segment, Section, TypeAndAttributes, Reserved2, Kind, Begin);
}
-void MCContext::renameELFSection(MCSectionELF *Section, StringRef Name) {
- StringRef GroupName;
- if (const MCSymbol *Group = Section->getGroup())
- GroupName = Group->getName();
-
- unsigned UniqueID = Section->getUniqueID();
- ELFUniquingMap.erase(
- ELFSectionKey{Section->getSectionName(), GroupName, UniqueID});
- auto I = ELFUniquingMap.insert(std::make_pair(
- ELFSectionKey{Name, GroupName, UniqueID},
- Section))
- .first;
- StringRef CachedName = I->first.SectionName;
- const_cast<MCSectionELF *>(Section)->setSectionName(CachedName);
-}
-
MCSectionELF *MCContext::createELFRelSection(StringRef Name, unsigned Type,
unsigned Flags, unsigned EntrySize,
const MCSymbolELF *Group,
Index: lib/MC/MCELFStreamer.cpp
===================================================================
--- lib/MC/MCELFStreamer.cpp
+++ lib/MC/MCELFStreamer.cpp
@@ -102,7 +102,7 @@
const MCSectionELF &Section =
static_cast<const MCSectionELF &>(*getCurrentSectionOnly());
- if (Section.getFlags() & ELF::SHF_TLS)
+ if (Section.Flags & ELF::SHF_TLS)
Symbol->setType(ELF::STT_TLS);
}
Index: lib/MC/MCSectionELF.cpp
===================================================================
--- lib/MC/MCSectionELF.cpp
+++ lib/MC/MCSectionELF.cpp
@@ -159,9 +159,7 @@
}
}
-bool MCSectionELF::UseCodeAlign() const {
- return getFlags() & ELF::SHF_EXECINSTR;
-}
+bool MCSectionELF::UseCodeAlign() const { return Flags & ELF::SHF_EXECINSTR; }
bool MCSectionELF::isVirtualSection() const {
return getType() == ELF::SHT_NOBITS;
Index: test/MC/ELF/compression.s
===================================================================
--- test/MC/ELF/compression.s
+++ test/MC/ELF/compression.s
@@ -3,13 +3,19 @@
// RUN: llvm-dwarfdump -debug-dump=info %t | FileCheck --check-prefix=INFO %s
// RUN: llvm-mc -filetype=obj -compress-debug-sections -triple i386-pc-linux-gnu < %s \
// RUN: | llvm-readobj -symbols - | FileCheck --check-prefix=386-SYMBOLS %s
+// RUN: llvm-readobj -sections %t | FileCheck --check-prefix=ZLIB %s
// REQUIRES: zlib
-// CHECK: Contents of section .zdebug_line:
-// Check for the 'ZLIB' file magic at the start of the section only
-// CHECK-NEXT: ZLIB
-// CHECK-NOT: ZLIB
+// Check that debug_line section was not renamed, so it is
+// zlib-style, not zlib-gnu one. Check that SHF_COMPRESSED was set.
+// ZLIB: Section {
+// ZLIB: Index:
+// ZLIB: Name: .debug_line
+// ZLIB-NEXT: Type: SHT_PROGBITS
+// ZLIB-NEXT: Flags [
+// ZLIB-NEXT: SHF_COMPRESSED
+// ZLIB-NEXT: ]
// Don't compress small sections, such as this simple debug_abbrev example
// CHECK: Contents of section .debug_abbrev:
@@ -30,7 +36,7 @@
// sections, so make sure we handle symbols inside compressed sections
// 386-SYMBOLS: Name: .Linfo_string0
// 386-SYMBOLS-NOT: }
-// 386-SYMBOLS: Section: .zdebug_str
+// 386-SYMBOLS: Section: .debug_str
.section .debug_line,"",@progbits