[llvm-strip] Support -s alias for --strip-all. Make both strip and objcopy case sensitive to support both -s (--strip-all) and -S (--strip-debug).

[rupprecht]

Summary

GNU strip supports both -s and -S as aliases for --strip-all and --strip-debug, respectfully.

As part of this, it turns out that strip/objcopy were accepting case insensitive command line args. I'm not sure if there was an explicit reason for this. The only others uses of this are llvm-cvtres/llvm-mt/llvm-lib, which are all tools specific for windows support. Forcing case sensitivity allows both aliases to exist, but seems like a good idea anyway.

And as a surprise test case adjustment, the llvm-strip unit test was running with -keep=unavailable_symbol, despite keep not be a valid flag for strip. This is because there is a flag -K which, when case insensitivity is permitted, allows it to be interpreted as -K = eep=unavailable_symbol (e.g. to allow -Kfoo == --keep-symbol=foo).

[rupprecht]

Rebase past rL344307

[jhenderson]

LGTM with the inline comment fixed.

I agree that command-line flags shouldn't be case-sensitive in general. I would expect e.g. -k and -K to be two different switches, and if one did not exist, then I'd expect an error.

test/tools/llvm-objcopy/strip-all.test

42–44

Nit: To reduce unnecessary changes in the diffs could you keep this as %t9, and move the llvm-strip -s case to below it, please.

[rupprecht]

• Reorder test cases for smaller diffs

[rupprecht]

test/tools/llvm-objcopy/strip-all.test

42–44

Done -- I kept it here and bumped up the next case (--keep-symbol) since that seems to be a different enough test case.

[jakehehrlich]

Looks like a strict improvement to me and a nice test case fix. Thanks!

LGTM.

test/tools/llvm-objcopy/strip-all.test

 # RUN: cp %t %t8
 # RUN: llvm-strip --strip-all %t8
 # RUN: cmp %t2 %t8
 
 # RUN: cp %t %t9
 # RUN: llvm-objcopy -S %t9 %t9
 # RUN: cmp %t2 %t9
 
+# RUN: cp %t %t10
+# RUN: llvm-strip -s %t10
+# RUN: cmp %t2 %t10
+
 # Verify that a non-existent symbol table (after first call to llvm-strip)
 # can be handled correctly.
-# RUN: cp %t %t9
-# RUN: llvm-strip --strip-all -keep=unavailable_symbol %t9
-# RUN: llvm-strip --strip-all -keep=unavailable_symbol %t9
-# RUN: cmp %t2 %t9
+# RUN: cp %t %t11
+# RUN: llvm-strip --strip-all --keep-symbol=unavailable_symbol %t11
+# RUN: llvm-strip --strip-all --keep-symbol=unavailable_symbol %t11
+# RUN: cmp %t2 %t11
 
 !ELF
 FileHeader:
   Class:           ELFCLASS64
   Data:            ELFDATA2LSB
   Type:            ET_REL
   Machine:         EM_X86_64
 Sections:

tools/llvm-objcopy/CopyConfig.cpp

#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
    ALIASARGS,                                                                  \
    VALUES},
 #include "ObjcopyOpts.inc"
 #undef OPTION
 };
 
 class ObjcopyOptTable : public opt::OptTable {
 public:
-  ObjcopyOptTable() : OptTable(ObjcopyInfoTable, true) {}
+  ObjcopyOptTable() : OptTable(ObjcopyInfoTable) {}
 };
 
 enum StripID {
   STRIP_INVALID = 0, // This is not an option ID.
 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
                HELPTEXT, METAVAR, VALUES)                                      \
   STRIP_##ID,
 #include "StripOpts.inc"
#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
    PARAM,          FLAGS,      STRIP_##GROUP,                                  \
    STRIP_##ALIAS,  ALIASARGS,  VALUES},
 #include "StripOpts.inc"
 #undef OPTION
 };
 
 class StripOptTable : public opt::OptTable {
 public:
-  StripOptTable() : OptTable(StripInfoTable, true) {}
+  StripOptTable() : OptTable(StripInfoTable) {}
 };
 
 enum SectionFlag {
   SecNone = 0,
   SecAlloc = 1 << 0,
   SecLoad = 1 << 1,
   SecNoload = 1 << 2,
   SecReadonly = 1 << 3,

tools/llvm-objcopy/StripOpts.td

 def preserve_dates : Flag<[ "-", "--" ], "preserve-dates">,
                      HelpText<"Preserve access and modification timestamps">;
 
 def p : Flag<[ "-" ], "p">, Alias<preserve_dates>;
 
 def strip_all : Flag<["-", "--"], "strip-all">,
                 HelpText<"Remove non-allocated sections other than .gnu.warning* sections">;
 
+def s : Flag<["-"], "s">,
+        Alias<strip_all>;
+
 def strip_debug : Flag<["-", "--"], "strip-debug">,
                   HelpText<"Remove debugging symbols only">;
 
 def d : Flag<["-"], "d">,
         Alias<strip_debug>;
 
 def g : Flag<["-"], "g">,
         Alias<strip_debug>;