[lld-macho] Use namespace qualifiers (macho::) instead of `namespace lld { namespace macho {`

[MaskRay]

Summary

See https://llvm.org/docs/CodingStandards.html#use-namespace-qualifiers-to-implement-previously-declared-functions
Similar to D79982.

[int3]

@MaskRay this seems to have broken the build on Windows: http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/16604/steps/stage%201%20build/logs/stdio

[MaskRay]

In D82432#2112587, @int3 wrote:

@MaskRay this seems to have broken the build on Windows: http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/16604/steps/stage%201%20build/logs/stdio

Should have been fixed by 40bc99538c85904e3f4de04c795bbebd4013bbe7 (hope reducing using namespace can be accepted)

Sorry for the breakage!

[MaskRay]

Bonus is that we can use Symbol instead of lld::macho::Symbol now.

[int3]

Hmm that's quite a bit of MachO:: sprinkled about but I guess it's fine. Thanks!

lld/MachO/ExportTrie.cpp

 
 struct ExportInfo {
   uint64_t address;
   // TODO: Add proper support for re-exports & stub-and-resolver flags.
 };
 
 } // namespace
 
-namespace lld {
-namespace macho {
-
-struct TrieNode {
+struct macho::TrieNode {
   std::vector<Edge> edges;
   Optional<ExportInfo> info;
   // Estimated offset from the start of the serialized trie to the current node.
   // This will converge to the true offset when updateOffset() is run to a
   // fixpoint.
   size_t offset = 0;
 
   // Returns whether the new estimated offset differs from the old one.
for (uint8_t i = 0; i < numEdges; ++i) {
     StringRef substring = StringRef(cbuf, strnlen(cbuf, end - buf));
     buf += substring.size() + 1;
     offset = decodeULEB128(buf, &ulebSize);
     buf += ulebSize;
     parse(start + offset, cumulativeString + substring);
   }
 }
 
-void parseTrie(const uint8_t *buf, size_t size,
+void macho::parseTrie(const uint8_t *buf, size_t size,
                       const TrieEntryCallback &callback) {
   if (size == 0)
     return;
 
   TrieParser(buf, size, callback).parse();
 }
-
-} // namespace macho
-} // namespace lld

lld/MachO/SyntheticSections.cpp

 #include "lld/Common/Memory.h"
 #include "llvm/Support/EndianStream.h"
 #include "llvm/Support/LEB128.h"
 
 using namespace llvm;
 using namespace llvm::MachO;
 using namespace llvm::support;
 using namespace llvm::support::endian;
+using namespace lld;
+using namespace lld::macho;
 
-namespace lld {
-namespace macho {
+InStruct macho::in;
+std::vector<SyntheticSection *> macho::syntheticSections;
 
 SyntheticSection::SyntheticSection(const char *segname, const char *name)
     : OutputSection(SyntheticKind, name), segname(segname) {
   syntheticSections.push_back(this);
 }
 
 // dyld3's MachOLoaded::getSlide() assumes that the __TEXT segment starts
 // from the beginning of the file (i.e. the header).

 
 void StringTableSection::writeTo(uint8_t *buf) const {
   uint32_t off = 0;
   for (StringRef str : strings) {
     memcpy(buf + off, str.data(), str.size());
     off += str.size() + 1; // account for null terminator
   }
 }
-
-InStruct in;
-std::vector<SyntheticSection *> syntheticSections;
-
-} // namespace macho
-} // namespace lld