Use zlib to uncompress debug sections in DWARF parser.
This makes llvm-dwarfdump and llvm-symbolizer understand
debug info sections compressed by ld.gold linker.
llvm-svn: 180088
diff --git a/llvm/cmake/config-ix.cmake b/llvm/cmake/config-ix.cmake
index c426f41..7c4285a 100755
--- a/llvm/cmake/config-ix.cmake
+++ b/llvm/cmake/config-ix.cmake
@@ -105,7 +105,11 @@
endif()
check_library_exists(dl dlopen "" HAVE_LIBDL)
check_library_exists(rt clock_gettime "" HAVE_LIBRT)
- check_library_exists(z compress2 "" HAVE_LIBZ)
+ if (LLVM_ENABLE_ZLIB)
+ check_library_exists(z compress2 "" HAVE_LIBZ)
+ else()
+ set(HAVE_LIBZ 0)
+ endif()
endif()
# function checks
diff --git a/llvm/lib/DebugInfo/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARFContext.cpp
index 74a8c36..1e13731 100644
--- a/llvm/lib/DebugInfo/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARFContext.cpp
@@ -10,6 +10,8 @@
#include "DWARFContext.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/Compression.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/Path.h"
@@ -483,6 +485,22 @@
return InliningInfo;
}
+static bool consumeCompressedDebugSectionHeader(StringRef &data,
+ uint64_t &OriginalSize) {
+ // Consume "ZLIB" prefix.
+ if (!data.startswith("ZLIB"))
+ return false;
+ data = data.substr(4);
+ // Consume uncompressed section size (big-endian 8 bytes).
+ DataExtractor extractor(data, false, 8);
+ uint32_t Offset = 0;
+ OriginalSize = extractor.getU64(&Offset);
+ if (Offset == 0)
+ return false;
+ data = data.substr(Offset);
+ return true;
+}
+
DWARFContextInMemory::DWARFContextInMemory(object::ObjectFile *Obj) :
IsLittleEndian(Obj->isLittleEndian()),
AddressSize(Obj->getBytesInAddress()) {
@@ -497,6 +515,22 @@
name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
+ // Check if debug info section is compressed with zlib.
+ if (name.startswith("zdebug_")) {
+ uint64_t OriginalSize;
+ if (!zlib::isAvailable() ||
+ !consumeCompressedDebugSectionHeader(data, OriginalSize))
+ continue;
+ OwningPtr<MemoryBuffer> UncompressedSection;
+ if (zlib::uncompress(data, UncompressedSection, OriginalSize) !=
+ zlib::StatusOK)
+ continue;
+ // Make data point to uncompressed section contents and save its contents.
+ name = name.substr(1);
+ data = UncompressedSection->getBuffer();
+ UncompressedSections.push_back(UncompressedSection.take());
+ }
+
StringRef *Section = StringSwitch<StringRef*>(name)
.Case("debug_info", &InfoSection)
.Case("debug_abbrev", &AbbrevSection)
@@ -584,4 +618,8 @@
}
}
+DWARFContextInMemory::~DWARFContextInMemory() {
+ DeleteContainerPointers(UncompressedSections);
+}
+
void DWARFContextInMemory::anchor() { }
diff --git a/llvm/lib/DebugInfo/DWARFContext.h b/llvm/lib/DebugInfo/DWARFContext.h
index 37b2729..78c18e6 100644
--- a/llvm/lib/DebugInfo/DWARFContext.h
+++ b/llvm/lib/DebugInfo/DWARFContext.h
@@ -161,8 +161,11 @@
StringRef RangeDWOSection;
StringRef AddrSection;
+ SmallVector<MemoryBuffer*, 4> UncompressedSections;
+
public:
DWARFContextInMemory(object::ObjectFile *);
+ ~DWARFContextInMemory();
virtual bool isLittleEndian() const { return IsLittleEndian; }
virtual uint8_t getAddressSize() const { return AddressSize; }
virtual const RelocAddrMap &infoRelocMap() const { return InfoRelocMap; }
diff --git a/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.cc b/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.cc
new file mode 100644
index 0000000..260c3c4
--- /dev/null
+++ b/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.cc
@@ -0,0 +1,24 @@
+class DummyClass {
+ int a_;
+ public:
+ DummyClass(int a) : a_(a) {}
+ int add(int b) {
+ return a_ + b;
+ }
+};
+
+int f(int a, int b) {
+ DummyClass c(a);
+ return c.add(b);
+}
+
+int main() {
+ return f(2, 3);
+}
+
+// Built with Clang 3.2 and ld.gold linker:
+// $ mkdir -p /tmp/dbginfo
+// $ cp dwarfdump-test-zlib.cc /tmp/dbginfo
+// $ cd /tmp/dbginfo
+// $ clang++ -g dwarfdump-test-zlib.cc -Wl,--compress-debug-sections=zlib \
+// -o <output>
diff --git a/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.elf-x86-64 b/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.elf-x86-64
new file mode 100755
index 0000000..16b3153
--- /dev/null
+++ b/llvm/test/DebugInfo/Inputs/dwarfdump-test-zlib.elf-x86-64
Binary files differ
diff --git a/llvm/test/DebugInfo/dwarfdump-zlib.test b/llvm/test/DebugInfo/dwarfdump-zlib.test
new file mode 100644
index 0000000..8ce2cf7
--- /dev/null
+++ b/llvm/test/DebugInfo/dwarfdump-zlib.test
@@ -0,0 +1,12 @@
+REQUIRES: zlib
+
+RUN: llvm-dwarfdump %p/Inputs/dwarfdump-test-zlib.elf-x86-64 \
+RUN: | FileCheck %s -check-prefix FULLDUMP
+RUN: llvm-dwarfdump %p/Inputs/dwarfdump-test-zlib.elf-x86-64 \
+RUN: --address=0x400559 --functions | FileCheck %s -check-prefix MAIN
+
+FULLDUMP: .debug_abbrev contents
+FULLDUMP: .debug_info contents
+
+MAIN: main
+MAIN-NEXT: /tmp/dbginfo{{[/\\]}}dwarfdump-test-zlib.cc:16
diff --git a/llvm/test/Makefile b/llvm/test/Makefile
index 8d05c57..2213319 100644
--- a/llvm/test/Makefile
+++ b/llvm/test/Makefile
@@ -141,6 +141,7 @@
@$(ECHOPATH) s=@LLVM_BINDINGS@=$(BINDINGS_TO_BUILD)=g >> lit.tmp
@$(ECHOPATH) s=@HOST_OS@=$(HOST_OS)=g >> lit.tmp
@$(ECHOPATH) s=@HOST_ARCH@=$(HOST_ARCH)=g >> lit.tmp
+ @$(ECHOPATH) s=@HAVE_LIBZ@=$(HAVE_LIBZ)=g >> lit.tmp
@sed -f lit.tmp $(PROJ_SRC_DIR)/lit.site.cfg.in > $@
@-rm -f lit.tmp
diff --git a/llvm/test/lit.cfg b/llvm/test/lit.cfg
index ea91f45..b423c6e 100644
--- a/llvm/test/lit.cfg
+++ b/llvm/test/lit.cfg
@@ -268,6 +268,9 @@
if not 'hexagon' in config.target_triple:
config.available_features.add("object-emission")
+if config.have_zlib == "1":
+ config.available_features.add("zlib")
+
# llc knows whether he is compiled with -DNDEBUG.
import subprocess
try:
diff --git a/llvm/test/lit.site.cfg.in b/llvm/test/lit.site.cfg.in
index 8024b24..3a680b2 100644
--- a/llvm/test/lit.site.cfg.in
+++ b/llvm/test/lit.site.cfg.in
@@ -19,6 +19,7 @@
config.host_arch = "@HOST_ARCH@"
config.llvm_use_intel_jitevents = "@LLVM_USE_INTEL_JITEVENTS@"
config.llvm_use_sanitizer = "@LLVM_USE_SANITIZER@"
+config.have_zlib = "@HAVE_LIBZ@"
# Support substitution of the tools_dir with user parameters. This is
# used when we can't determine the tool dir at configuration time.