[ELF] - Implemented --print-gc-sections command line argument.
List all sections removed by garbage collection. This option is only effective if garbage collection has been enabled via the `--gc-sections' option.
Differential revision: http://reviews.llvm.org/D15327
llvm-svn: 255235
diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 465dc68..1a86881 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -16,6 +16,7 @@
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Support/FileOutputBuffer.h"
+#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/StringSaver.h"
using namespace llvm;
@@ -532,6 +533,15 @@
}
template <class ELFT>
+void reportDiscarded(InputSectionBase<ELFT> *IS,
+ const std::unique_ptr<ObjectFile<ELFT>> &File) {
+ if (!Config->PrintGcSections || !IS || IS->isLive())
+ return;
+ llvm::errs() << "removing unused section from '" << IS->getSectionName()
+ << "' in file '" << File->getName() << "'\n";
+}
+
+template <class ELFT>
bool Writer<ELFT>::isDiscarded(InputSectionBase<ELFT> *IS) const {
if (!IS || !IS->isLive() || IS == &InputSection<ELFT>::Discarded)
return true;
@@ -564,8 +574,10 @@
for (const std::unique_ptr<ObjectFile<ELFT>> &F : Symtab.getObjectFiles()) {
for (InputSectionBase<ELFT> *C : F->getSections()) {
- if (isDiscarded(C))
+ if (isDiscarded(C)) {
+ reportDiscarded(C, F);
continue;
+ }
const Elf_Shdr *H = C->getSectionHdr();
uintX_t OutFlags = H->sh_flags & ~SHF_GROUP;
// For SHF_MERGE we create different output sections for each sh_entsize.