auto merge of #13117 : alexcrichton/rust/no-crate-map, r=brson

This can be done now that logging has been moved out and libnative is the default (not libgreen)

Author: bors

src/compiletest/compiletest.rs

@@ -43,7 +43,9 @@ pub mod common;
 pub mod errors;
 
 #[start]
-fn start(argc: int, argv: **u8) -> int { green::start(argc, argv, main) }
+fn start(argc: int, argv: **u8) -> int {
+    green::start(argc, argv, rustuv::event_loop, main)
+}
 
 pub fn main() {
     let args = os::args();

src/doc/guide-runtime.md

@@ -223,27 +223,49 @@ Having a default decision made in the compiler is done out of necessity and
 convenience. The compiler's decision of runtime to link to is *not* an
 endorsement of one over the other. As always, this decision can be overridden.
 
-For example, this program will be linked to "the default runtime"
+For example, this program will be linked to "the default runtime". The current
+default runtime is to use libnative.
 
 ~~~{.rust}
 fn main() {}
 ~~~
 
-Whereas this program explicitly opts into using a particular runtime
+### Force booting with libgreen
+
+In this example, the `main` function will be booted with I/O support powered by
+libuv. This is done by linking to the `rustuv` crate and specifying the
+`rustuv::event_loop` function as the event loop factory.
+
+To create a pool of green tasks which have no I/O support, you may shed the
+`rustuv` dependency and use the `green::basic::event_loop` function instead of
+`rustuv::event_loop`. All tasks will have no I/O support, but they will still be
+able to deschedule/reschedule (use channels, locks, etc).
 
 ~~~{.rust}
 extern crate green;
+extern crate rustuv;
 
 #[start]
 fn start(argc: int, argv: **u8) -> int {
-    green::start(argc, argv, main)
+    green::start(argc, argv, rustuv::event_loop, main)
 }
 
 fn main() {}
 ~~~
 
-Both libgreen/libnative provide a top-level `start` function which is used to
-boot an initial Rust task in that specified runtime.
+### Force booting with libnative
+
+This program's `main` function will always be booted with libnative, running
+inside of an OS thread.
+
+~~~{.rust}
+extern crate native;
+
+#[start]
+fn start(argc: int, argv: **u8) -> int { native::start(argc, argv, main) }
+
+fn main() {}
+~~~
 
 # Finding the runtime
 

src/libgreen/basic.rs

@@ -237,7 +237,7 @@ mod test {
     fn pool() -> SchedPool {
         SchedPool::new(PoolConfig {
             threads: 1,
-            event_loop_factory: Some(basic::event_loop),
+            event_loop_factory: basic::event_loop,
         })
     }
 
@@ -267,7 +267,7 @@ mod test {
     fn multi_thread() {
         let mut pool = SchedPool::new(PoolConfig {
             threads: 2,
-            event_loop_factory: Some(basic::event_loop),
+            event_loop_factory: basic::event_loop,
         });
 
         for _ in range(0, 20) {

src/libgreen/lib.rs

@@ -116,13 +116,34 @@
 //! extern crate green;
 //!
 //! #[start]
-//! fn start(argc: int, argv: **u8) -> int { green::start(argc, argv, main) }
+//! fn start(argc: int, argv: **u8) -> int {
+//!     green::start(argc, argv, green::basic::event_loop, main)
+//! }
 //!
 //! fn main() {
 //!     // this code is running in a pool of schedulers
 //! }
 //! ```
 //!
+//! > **Note**: This `main` funciton in this example does *not* have I/O
+//! >           support. The basic event loop does not provide any support
+//!
+//! # Starting with I/O support in libgreen
+//!
+//! ```rust
+//! extern crate green;
+//! extern crate rustuv;
+//!
+//! #[start]
+//! fn start(argc: int, argv: **u8) -> int {
+//!     green::start(argc, argv, rustuv::event_loop, main)
+//! }
+//!
+//! fn main() {
+//!     // this code is running in a pool of schedulers all powered by libuv
+//! }
+//! ```
+//!
 //! # Using a scheduler pool
 //!
 //! ```rust
@@ -176,11 +197,11 @@
 #[allow(visible_private_types)];
 
 #[cfg(test)] #[phase(syntax, link)] extern crate log;
+#[cfg(test)] extern crate rustuv;
 extern crate rand;
 
 use std::mem::replace;
 use std::os;
-use std::rt::crate_map;
 use std::rt::rtio;
 use std::rt::thread::Thread;
 use std::rt;
@@ -225,12 +246,14 @@ pub mod task;
 ///
 /// The return value is used as the process return code. 0 on success, 101 on
 /// error.
-pub fn start(argc: int, argv: **u8, main: proc()) -> int {
+pub fn start(argc: int, argv: **u8,
+             event_loop_factory: fn() -> ~rtio::EventLoop,
+             main: proc()) -> int {
     rt::init(argc, argv);
     let mut main = Some(main);
     let mut ret = None;
     simple::task().run(|| {
-        ret = Some(run(main.take_unwrap()));
+        ret = Some(run(event_loop_factory, main.take_unwrap()));
     });
     // unsafe is ok b/c we're sure that the runtime is gone
     unsafe { rt::cleanup() }
@@ -245,10 +268,12 @@ pub fn start(argc: int, argv: **u8, main: proc()) -> int {
 ///
 /// This function will not return until all schedulers in the associated pool
 /// have returned.
-pub fn run(main: proc()) -> int {
+pub fn run(event_loop_factory: fn() -> ~rtio::EventLoop, main: proc()) -> int {
     // Create a scheduler pool and spawn the main task into this pool. We will
     // get notified over a channel when the main task exits.
-    let mut pool = SchedPool::new(PoolConfig::new());
+    let mut cfg = PoolConfig::new();
+    cfg.event_loop_factory = event_loop_factory;
+    let mut pool = SchedPool::new(cfg);
     let (tx, rx) = channel();
     let mut opts = TaskOpts::new();
     opts.notify_chan = Some(tx);
@@ -273,7 +298,7 @@ pub struct PoolConfig {
     threads: uint,
     /// A factory function used to create new event loops. If this is not
     /// specified then the default event loop factory is used.
-    event_loop_factory: Option<fn() -> ~rtio::EventLoop>,
+    event_loop_factory: fn() -> ~rtio::EventLoop,
 }
 
 impl PoolConfig {
@@ -282,7 +307,7 @@ impl PoolConfig {
     pub fn new() -> PoolConfig {
         PoolConfig {
             threads: rt::default_sched_threads(),
-            event_loop_factory: None,
+            event_loop_factory: basic::event_loop,
         }
     }
 }
@@ -324,7 +349,6 @@ impl SchedPool {
             threads: nscheds,
             event_loop_factory: factory
         } = config;
-        let factory = factory.unwrap_or(default_event_loop_factory());
         assert!(nscheds > 0);
 
         // The pool of schedulers that will be returned from this function
@@ -493,20 +517,3 @@ impl Drop for SchedPool {
         }
     }
 }
-
-fn default_event_loop_factory() -> fn() -> ~rtio::EventLoop {
-    match crate_map::get_crate_map() {
-        None => {}
-        Some(map) => {
-            match map.event_loop_factory {
-                None => {}
-                Some(factory) => return factory
-            }
-        }
-    }
-
-    // If the crate map didn't specify a factory to create an event loop, then
-    // instead just use a basic event loop missing all I/O services to at least
-    // get the scheduler running.
-    return basic::event_loop;
-}

src/libgreen/sched.rs

@@ -1003,6 +1003,8 @@ fn new_sched_rng() -> XorShiftRng {
 
 #[cfg(test)]
 mod test {
+    use rustuv;
+
     use std::comm;
     use std::task::TaskOpts;
     use std::rt::Runtime;
@@ -1017,7 +1019,7 @@ mod test {
     fn pool() -> SchedPool {
         SchedPool::new(PoolConfig {
             threads: 1,
-            event_loop_factory: Some(basic::event_loop),
+            event_loop_factory: basic::event_loop,
         })
     }
 
@@ -1262,7 +1264,7 @@ mod test {
 
         let mut pool = SchedPool::new(PoolConfig {
             threads: 2,
-            event_loop_factory: None,
+            event_loop_factory: rustuv::event_loop,
         });
 
         // This is a regression test that when there are no schedulable tasks in
@@ -1413,7 +1415,7 @@ mod test {
     fn dont_starve_1() {
         let mut pool = SchedPool::new(PoolConfig {
             threads: 2, // this must be > 1
-            event_loop_factory: Some(basic::event_loop),
+            event_loop_factory: basic::event_loop,
         });
         pool.spawn(TaskOpts::new(), proc() {
             let (tx, rx) = channel();

src/libgreen/task.rs

@@ -494,7 +494,7 @@ mod tests {
     fn spawn_opts(opts: TaskOpts, f: proc()) {
         let mut pool = SchedPool::new(PoolConfig {
             threads: 1,
-            event_loop_factory: None,
+            event_loop_factory: ::rustuv::event_loop,
         });
         pool.spawn(opts, f);
         pool.shutdown();

src/librustc/driver/session.rs

@@ -451,8 +451,6 @@ cgoptions!(
         "don't run LLVM's SLP vectorization pass"),
     soft_float: bool = (false, parse_bool,
         "generate software floating point library calls"),
-    gen_crate_map: bool = (false, parse_bool,
-        "force generation of a toplevel crate map"),
     prefer_dynamic: bool = (false, parse_bool,
         "prefer dynamic linking to static linking"),
     no_integrated_as: bool = (false, parse_bool,

src/librustc/middle/lang_items.rs

@@ -254,8 +254,6 @@ lets_do_this! {
     TyVisitorTraitLangItem,          "ty_visitor",              ty_visitor;
     OpaqueStructLangItem,            "opaque",                  opaque;
 
-    EventLoopFactoryLangItem,        "event_loop_factory",      event_loop_factory;
-
     TypeIdLangItem,                  "type_id",                 type_id;
 
     EhPersonalityLangItem,           "eh_personality",          eh_personality_fn;

src/librustc/middle/lint.rs

@@ -980,7 +980,7 @@ static other_attrs: &'static [&'static str] = &[
     "thread_local", // for statics
     "allow", "deny", "forbid", "warn", // lint options
     "deprecated", "experimental", "unstable", "stable", "locked", "frozen", //item stability
-    "crate_map", "cfg", "doc", "export_name", "link_section",
+    "cfg", "doc", "export_name", "link_section",
     "no_mangle", "static_assert", "unsafe_no_drop_flag", "packed",
     "simd", "repr", "deriving", "unsafe_destructor", "link", "phase",
     "macro_export", "must_use", "automatically_derived",

src/librustc/middle/trans/base.rs

@@ -76,7 +76,7 @@ use std::c_str::ToCStr;
 use std::cell::{Cell, RefCell};
 use std::libc::c_uint;
 use std::local_data;
-use syntax::abi::{X86, X86_64, Arm, Mips, Rust, RustIntrinsic, OsWin32};
+use syntax::abi::{X86, X86_64, Arm, Mips, Rust, RustIntrinsic};
 use syntax::ast_map::PathName;
 use syntax::ast_util::{local_def, is_local};
 use syntax::attr::AttrMetaMethods;
@@ -2316,65 +2316,6 @@ pub fn symname(name: &str, hash: &str, vers: &str) -> ~str {
     link::exported_name(ast_map::Values(path.iter()).chain(None), hash, vers)
 }
 
-pub fn decl_crate_map(ccx: &mut CrateContext) {
-    let mut n_subcrates = 1;
-    while ccx.sess().cstore.have_crate_data(n_subcrates) {
-        n_subcrates += 1;
-    }
-    let is_top = !ccx.sess().building_library.get() || ccx.sess().opts.cg.gen_crate_map;
-    let sym_name = if is_top {
-        ~"_rust_crate_map_toplevel"
-    } else {
-        symname("_rust_crate_map_" + ccx.link_meta.crateid.name,
-                ccx.link_meta.crate_hash.as_str(),
-                ccx.link_meta.crateid.version_or_default())
-    };
-
-    let maptype = Type::struct_(ccx, [
-        Type::i32(ccx),        // version
-        ccx.int_type.ptr_to(), // event loop factory
-    ], false);
-    let map = sym_name.with_c_str(|buf| {
-        unsafe {
-            llvm::LLVMAddGlobal(ccx.llmod, maptype.to_ref(), buf)
-        }
-    });
-    lib::llvm::SetLinkage(map, lib::llvm::ExternalLinkage);
-
-    // On windows we'd like to export the toplevel cratemap
-    // such that we can find it from libstd.
-    if ccx.sess().targ_cfg.os == OsWin32 && is_top {
-        unsafe { llvm::LLVMRustSetDLLExportStorageClass(map) }
-    }
-
-    ccx.crate_map_name = sym_name;
-    ccx.crate_map = map;
-}
-
-pub fn fill_crate_map(ccx: &CrateContext, map: ValueRef) {
-    let event_loop_factory = match ccx.tcx.lang_items.event_loop_factory() {
-        Some(did) => unsafe {
-            if is_local(did) {
-                llvm::LLVMConstPointerCast(get_item_val(ccx, did.node),
-                                           ccx.int_type.ptr_to().to_ref())
-            } else {
-                let name = csearch::get_symbol(&ccx.sess().cstore, did);
-                let global = name.with_c_str(|buf| {
-                    llvm::LLVMAddGlobal(ccx.llmod, ccx.int_type.to_ref(), buf)
-                });
-                global
-            }
-        },
-        None => C_null(ccx.int_type.ptr_to())
-    };
-    unsafe {
-        llvm::LLVMSetInitializer(map, C_struct(ccx,
-            [C_i32(ccx, 2),
-            event_loop_factory,
-        ], false));
-    }
-}
-
 pub fn crate_ctxt_to_encode_parms<'r>(cx: &'r CrateContext, ie: encoder::EncodeInlinedItem<'r>)
     -> encoder::EncodeParams<'r> {
 
@@ -2467,26 +2408,6 @@ pub fn trans_crate(krate: ast::Crate,
         trans_mod(&ccx, &krate.module);
     }
 
-    fill_crate_map(&ccx, ccx.crate_map);
-
-    // win32: wart with exporting crate_map symbol
-    // We set the crate map (_rust_crate_map_toplevel) to use dll_export
-    // linkage but that ends up causing the linker to look for a
-    // __rust_crate_map_toplevel symbol (extra underscore) which it will
-    // subsequently fail to find. So to mitigate that we just introduce
-    // an alias from the symbol it expects to the one that actually exists.
-    if ccx.sess().targ_cfg.os == OsWin32 && !ccx.sess().building_library.get() {
-
-        let maptype = val_ty(ccx.crate_map).to_ref();
-
-        "__rust_crate_map_toplevel".with_c_str(|buf| {
-            unsafe {
-                llvm::LLVMAddAlias(ccx.llmod, maptype,
-                                   ccx.crate_map, buf);
-            }
-        })
-    }
-
     glue::emit_tydescs(&ccx);
     if ccx.sess().opts.debuginfo != NoDebugInfo {
         debuginfo::finalize(&ccx);
@@ -2537,7 +2458,6 @@ pub fn trans_crate(krate: ast::Crate,
     // symbol. This symbol is required for use by the libmorestack library that
     // we link in, so we must ensure that this symbol is not internalized (if
     // defined in the crate).
-    reachable.push(ccx.crate_map_name.to_owned());
     reachable.push(~"main");
     reachable.push(~"rust_stack_exhausted");
     reachable.push(~"rust_eh_personality"); // referenced from .eh_frame section on some platforms