[SR-2401] Macros with bitwise operations should be imported

[belkadan]

Previous ID	SR-2401
Radar	rdar://problem/18706771
Original Reporter	@belkadan
Type	Bug

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, ClangImporter, Macros
Assignee	None
Priority	Medium

md5: bf817a076ddc93edd071b2f1d749c10d

relates to:

• SR-2402 Clang importer should import nullary function-like macros
• SR-2530 Import macros containing string concatenation

Issue Description:

#define AVAILABLE_VALUE         0x10000
#define NOT_AVAILABLE_VALUE     (AVAILABLE_VALUE | 1)

Swift can see AVAILABLE_VALUE, but not NOT_AVAILABLE_VALUE because it has bitwise operations in it. Ideally the compiler should assume the identifier refers to a previous macro and constant-fold this.