Re-commit r223330: Rewrite InputGraph's Group
llvm-svn: 223867
diff --git a/lld/lib/ReaderWriter/MachO/MachOLinkingContext.cpp b/lld/lib/ReaderWriter/MachO/MachOLinkingContext.cpp
index 3e91e4a..b129c03 100644
--- a/lld/lib/ReaderWriter/MachO/MachOLinkingContext.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachOLinkingContext.cpp
@@ -22,6 +22,7 @@
#include "llvm/ADT/Triple.h"
#include "llvm/Config/config.h"
#include "llvm/Support/Errc.h"
+#include "llvm/Support/Debug.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/MachO.h"
#include "llvm/Support/Path.h"
@@ -923,4 +924,35 @@
return true;
}
+static File *getFirstFile(const std::unique_ptr<InputElement> &elem) {
+ FileNode *e = dyn_cast<FileNode>(const_cast<InputElement *>(elem.get()));
+ if (!e || e->files().empty())
+ return nullptr;
+ return e->files()[0].get();
+}
+
+static bool isLibrary(const std::unique_ptr<InputElement> &elem) {
+ File *f = getFirstFile(elem);
+ return f && (isa<SharedLibraryFile>(f) || isa<ArchiveLibraryFile>(f));
+}
+
+// The darwin linker processes input files in two phases. The first phase
+// links in all object (.o) files in command line order. The second phase
+// links in libraries in command line order.
+// In this function we reorder the input files so that all the object files
+// comes before any library file. We also make a group for the library files
+// so that the Resolver will reiterate over the libraries as long as we find
+// new undefines from libraries.
+void MachOLinkingContext::maybeSortInputFiles() {
+ std::vector<std::unique_ptr<InputElement>> &elements
+ = getInputGraph().inputElements();
+ std::stable_sort(elements.begin(), elements.end(),
+ [](const std::unique_ptr<InputElement> &a,
+ const std::unique_ptr<InputElement> &b) {
+ return !isLibrary(a) && isLibrary(b);
+ });
+ size_t numLibs = std::count_if(elements.begin(), elements.end(), isLibrary);
+ elements.push_back(llvm::make_unique<GroupEnd>(numLibs));
+}
+
} // end namespace lld