diff --git a/NOTES.txt b/NOTES.txt index 6e6c57534ce..3b5ad16e3e1 100644 --- a/NOTES.txt +++ b/NOTES.txt @@ -48,55 +48,6 @@ TODO: File Manager Speedup: 3. Reading the dir uses the getdirentries syscall, creating an FileEntry for all files found. -//===---------------------------------------------------------------------===// - -TODO: Fast #Import: - - * Get frameworks that don't use #import to do so, e.g. - DirectoryService, AudioToolbox, CoreFoundation, etc. Why not using #import? - Because they work in C mode? C has #import. - * Have the lexer return a token for #import instead of handling it itself. - - Create a new preprocessor object with no external state (no -D/U options - from the command line, etc). Alternatively, keep track of exactly which - external state is used by a #import: declare it somehow. - * When having reading a #import file, keep track of whether we have (and/or - which) seen any "configuration" macros. Various cases: - - Uses of target args (__POWERPC__, __i386): Header has to be parsed - multiple times, per-target. What about #ifndef checks? How do we know? - - "Configuration" preprocessor macros not defined: POWERPC, etc. What about - things like __STDC__ etc? What is and what isn't allowed. - * Special handling for "umbrella" headers, which just contain #import stmts: - - Cocoa.h/AppKit.h - Contain pointers to digests instead of entire digests - themselves? Foundation.h isn't pure umbrella! - * Frameworks digests: - - Can put "digest" of a framework-worth of headers into the framework - itself. To open AppKit, just mmap - /System/Library/Frameworks/AppKit.framework/"digest", which provides a - symbol table in a well defined format. Lazily unstream stuff that is - needed. Contains declarations, macros, and debug information. - - System frameworks ship with digests. How do we handle configuration - information? How do we handle stuff like: - #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_2 - which guards a bunch of decls? Should there be a couple of default - configs, then have the UI fall back to building/caching its own? - - GUI automatically builds digests when UI is idle, both of system - frameworks if they aren't not available in the right config, and of app - frameworks. - - GUI builds dependence graph of frameworks/digests based on #imports. If a - digest is out date, dependent digests are automatically invalidated. - - * New constraints on #import for objc-v3: - - #imported file must not define non-inline function bodies. - - Alternatively, they can, and these bodies get compiled/linked *once* - per app into a dylib. What about building user dylibs? - - Restrictions on ObjC grammar: can't #import the body of a for stmt or fn. - - Compiler must detect and reject these cases. - - #defines defined within a #import have two behaviors: - - By default, they escape the header. These macros *cannot* be #undef'd - by other code: this is enforced by the front-end. - - Optionally, user can specify what macros escape (whitelist) or can use - #undef. - //===---------------------------------------------------------------------===// // Specifying targets: -triple and -arch ===---------------------------------------------------------------------===//