Add --strip-all option back to llvm-strip.

Summary:
This option appears to have been dropped as part of the refactoring in
r331663. Unfortunately, if we want to use llvm-strip as a drop-in
replacement for strip, this option should still be available.

Reviewers: alexshap

Reviewed By: alexshap

Subscribers: meikeb, kongyi, chh, jakehehrlich, llvm-commits, pirama

Differential Revision: https://reviews.llvm.org/D49226

llvm-svn: 336921
diff --git a/llvm/tools/llvm-objcopy/StripOpts.td b/llvm/tools/llvm-objcopy/StripOpts.td
index 5825f23..333b0d2 100644
--- a/llvm/tools/llvm-objcopy/StripOpts.td
+++ b/llvm/tools/llvm-objcopy/StripOpts.td
@@ -11,6 +11,9 @@
               MetaVarName<"output">,
               HelpText<"Write output to <file>">;
 
+def strip_all : Flag<["-", "--"], "strip-all">,
+                HelpText<"Remove non-allocated sections other than .gnu.warning* sections">;
+
 def strip_debug : Flag<["-", "--"], "strip-debug">,
                   HelpText<"Remove debugging symbols only">;
 
diff --git a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
index c28862f..a4936dd 100644
--- a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
+++ b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp
@@ -655,6 +655,7 @@
 
   Config.DiscardAll = InputArgs.hasArg(STRIP_discard_all);
   Config.StripUnneeded = InputArgs.hasArg(STRIP_strip_unneeded);
+  Config.StripAll = InputArgs.hasArg(STRIP_strip_all);
 
   if (!Config.StripDebug && !Config.StripUnneeded && !Config.DiscardAll)
     Config.StripAll = true;