macros but doesn't expand #includes, remove comments, remove #defines
etc.
For example:
----
#include <stdio.h>
#define bbaa
#define funclike(x) x "a" x "b" x
bbaa bbaa
#if 1
funclike("gar")
foo /*blah*/ bar
bar
#endif
#if 0
funclike()
#endif
----
rewrites to:
----
#include <stdio.h>
#define bbaa
#define funclike(x) x "a" x "b" x
/*bbaa bbaa*/
#if 1
"gar" "a" "gar" "b" "gar"/*funclike*//*("gar")*/
foo /*blah*/ bar
bar
#endif
#if 0
/*funclike()*/
#endif
----
llvm-svn: 50925