[ELF] - Introduce StripPolicy instead of Config->StripAll/StripDebug flags.

This approach is not only consistent with UnresolvedPolicy, 
but also should help to solve a problem 
of options with opposing meanings, mentioned in PR28843

Differential revision: https://reviews.llvm.org/D23869

llvm-svn: 280206

4 files changed, 20 insertions, 13 deletions

diff --git a/lld/ELF/Config.h b/lld/ELF/Config.h
index 1144b2fa159..25ec18b64d2 100644
--- a/lld/ELF/Config.h
+++ b/lld/ELF/Config.h
@@ -30,8 +30,13 @@ enum ELFKind {
   ELF64BEKind
 };
 
+// For --build-id.
 enum class BuildIdKind { None, Fnv1, Md5, Sha1, Hexstring, Uuid };
 
+// For --strip-{all,debug}.
+enum class StripPolicy { None, All, Debug };
+
+// For --unresolved-symbols.
 enum class UnresolvedPolicy { NoUndef, Error, Warn, Ignore };
 
 struct SymbolVersion {
@@ -101,8 +106,6 @@ struct Configuration {
   bool SaveTemps;
   bool Shared;
   bool Static = false;
-  bool StripAll;
-  bool StripDebug;
   bool SysvHash = true;
   bool Target1Rel;
   bool Threads;
@@ -115,6 +118,7 @@ struct Configuration {
   bool ZNow;
   bool ZOrigin;
   bool ZRelro;
+  StripPolicy Strip = StripPolicy::None;
   UnresolvedPolicy UnresolvedSymbols;
   BuildIdKind BuildId = BuildIdKind::None;
   ELFKind EKind = ELFNoneKind;
diff --git a/lld/ELF/Driver.cpp b/lld/ELF/Driver.cpp
index 89d5bb51163..3f2071b1fdf 100644
--- a/lld/ELF/Driver.cpp
+++ b/lld/ELF/Driver.cpp
@@ -344,6 +344,15 @@ static bool isOutputFormatBinary(opt::InputArgList &Args) {
   return false;
 }
 
+static StripPolicy getStripOption(opt::InputArgList &Args) {
+  if (auto *Arg = Args.getLastArg(OPT_strip_all, OPT_strip_debug)) {
+    if (Arg->getOption().getID() == OPT_strip_all)
+      return StripPolicy::All;
+    return StripPolicy::Debug;
+  }
+  return StripPolicy::None;
+}
+
 // Initializes Config members by the command line options.
 void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   for (auto *Arg : Args.filtered(OPT_L))
@@ -383,8 +392,6 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->Relocatable = Args.hasArg(OPT_relocatable);
   Config->SaveTemps = Args.hasArg(OPT_save_temps);
   Config->Shared = Args.hasArg(OPT_shared);
-  Config->StripAll = Args.hasArg(OPT_strip_all);
-  Config->StripDebug = Args.hasArg(OPT_strip_debug);
   Config->Target1Rel = Args.hasArg(OPT_target1_rel);
   Config->Threads = Args.hasArg(OPT_threads);
   Config->Trace = Args.hasArg(OPT_trace);
@@ -416,17 +423,13 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->ZOrigin = hasZOption(Args, "origin");
   Config->ZRelro = !hasZOption(Args, "norelro");
 
+  if (!Config->Relocatable)
+    Config->Strip = getStripOption(Args);
+
   if (Optional<StringRef> Value = getZOptionValue(Args, "stack-size"))
     if (Value->getAsInteger(0, Config->ZStackSize))
       error("invalid stack size: " + *Value);
 
-  if (Config->Relocatable)
-    Config->StripAll = false;
-
-  // --strip-all implies --strip-debug.
-  if (Config->StripAll)
-    Config->StripDebug = true;
-
   // Config->Pic is true if we are generating position-independent code.
   Config->Pic = Config->Pie || Config->Shared;
 
diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
index e0fd5f475b6..71ca4a1934e 100644
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -323,7 +323,7 @@ elf::ObjectFile<ELFT>::createInputSection(const Elf_Shdr &Sec) {
     return &InputSection<ELFT>::Discarded;
   }
 
-  if (Config->StripDebug && Name.startswith(".debug"))
+  if (Config->Strip != StripPolicy::None && Name.startswith(".debug"))
     return &InputSection<ELFT>::Discarded;
 
   // The linker merges EH (exception handling) frames and creates a
diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 8543fbf83d9..1c1f02c22c0 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -176,7 +176,7 @@ template <class ELFT> void elf::writeResult() {
   StringRef S = Config->Rela ? ".rela.plt" : ".rel.plt";
   GotPlt.reset(new GotPltSection<ELFT>);
   RelaPlt.reset(new RelocationSection<ELFT>(S, false /*Sort*/));
-  if (!Config->StripAll) {
+  if (Config->Strip != StripPolicy::All) {
     StrTab.reset(new StringTableSection<ELFT>(".strtab", false));
     SymTabSec.reset(new SymbolTableSection<ELFT>(*StrTab));
   }