Option parsing: add support for alias arguments.

This makes option aliases more powerful by enabling them to
pass along arguments to the option they're aliasing.

For example, if we have a joined option "-foo=", we can now
specify a flag option "-bar" to be an alias of that, with the
argument "baz".

This is especially useful for the cl.exe compatible clang driver,
where many options are aliases. For example, this patch enables
us to alias "/Ox" to "-O3" (-O is a joined option), and "/WX" to
"-Werror" (again, -W is a joined option).

Differential Revision: http://llvm-reviews.chandlerc.com/D1245

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187537 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 19 insertions, 3 deletions

diff --git a/unittests/Option/OptionParsingTest.cpp b/unittests/Option/OptionParsingTest.cpp
index 2c4fdcfa2c7..101568a567e 100644
--- a/unittests/Option/OptionParsingTest.cpp
+++ b/unittests/Option/OptionParsingTest.cpp
@@ -17,9 +17,11 @@
 using namespace llvm;
 using namespace llvm::opt;
 
+#define SUPPORT_ALIASARGS // FIXME: Remove when no longer necessary.
+
 enum ID {
   OPT_INVALID = 0, // This is not an option ID.
-#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, FLAGS, PARAM, \
+#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM, \
               HELPTEXT, METAVAR) OPT_##ID,
 #include "Opts.inc"
   LastOption
@@ -37,10 +39,10 @@ enum OptionFlags {
 };
 
 static const OptTable::Info InfoTable[] = {
-#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, FLAGS, PARAM, \
+#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM, \
                HELPTEXT, METAVAR)   \
   { PREFIX, NAME, HELPTEXT, METAVAR, OPT_##ID, Option::KIND##Class, PARAM, \
-    FLAGS, OPT_##GROUP, OPT_##ALIAS },
+    FLAGS, OPT_##GROUP, OPT_##ALIAS, ALIASARGS },
 #include "Opts.inc"
 #undef OPTION
 };
@@ -145,3 +147,14 @@ TEST(Option, ParseAliasInGroup) {
   OwningPtr<InputArgList> AL(T.ParseArgs(MyArgs, array_endof(MyArgs), MAI, MAC));
   EXPECT_TRUE(AL->hasArg(OPT_H));
 }
+
+TEST(Option, AliasArgs) {
+  TestOptTable T;
+  unsigned MAI, MAC;
+
+  const char *MyArgs[] = { "-J", "-Joo" };
+  OwningPtr<InputArgList> AL(T.ParseArgs(MyArgs, array_endof(MyArgs), MAI, MAC));
+  EXPECT_TRUE(AL->hasArg(OPT_B));
+  EXPECT_EQ(AL->getAllArgValues(OPT_B)[0], "foo");
+  EXPECT_EQ(AL->getAllArgValues(OPT_B)[1], "bar");
+}
diff --git a/unittests/Option/Opts.td b/unittests/Option/Opts.td
index 8e33ba8580b..986b3122af7 100644
--- a/unittests/Option/Opts.td
+++ b/unittests/Option/Opts.td
@@ -19,3 +19,6 @@ def H : Flag<["-"], "H">, Flags<[HelpHidden]>;
 
 def my_group : OptionGroup<"my group">;
 def I : Flag<["-"], "I">, Alias<H>, Group<my_group>;
+
+def J : Flag<["-"], "J">, Alias<B>, AliasArgs<["foo"]>;
+def Joo : Flag<["-"], "Joo">, Alias<B>, AliasArgs<["bar"]>;