This is the second of two parts of #8991, now possible as a new snapshot
has been made. (The first part implemented the unreachable!() macro; it
was #8992, 6b7b8f2682.)
``std::util::unreachable()`` is removed summarily; any code which used
it should now use the ``unreachable!()`` macro.
Closes#9312.
Closes#8991.
If a static is flagged as address_insignificant, then for LLVM to actually
perform the relevant optimization it must have an internal linkage type. What
this means, though, is that the static will not be available to other crates.
Hence, if you have a generic function with an inner static, it will fail to link
when built as a library because other crates will attempt to use the inner
static externally.
This gets around the issue by inlining the static into the metadata. The same
relevant optimization is then applied separately in the external crate. What
this ends up meaning is that all statics tagged with #[address_insignificant]
will appear at most once per crate (by value), but they could appear in multiple
crates.
This should be the last blocker for using format! ...
This doesn't close any bugs as the goal is to convert the parameter to by-value, but this is a step towards being able to make guarantees about `&T` pointers (where T is Freeze) to LLVM.
In #8185 cross-crate condition handlers were fixed by ensuring that globals
didn't start appearing in different crates with different addressed. An
unfortunate side effect of that pull request is that constants weren't inlined
across crates (uint::bits is unknown to everything but libstd).
This commit fixes this inlining by using the `available_eternally` linkage
provided by LLVM. It partially reverts #8185, and then adds support for this
linkage type. The main caveat is that not all statics could be inlined into
other crates. Before this patch, all statics were considered "inlineable items",
but an unfortunate side effect of how we deal with `&static` and `&[static]`
means that these two cases cannot be inlined across crates. The translation of
constants was modified to propogate this condition of whether a constant
should be considered inlineable into other crates.
Closes#9036
also removes the unused `FastInvoke` wrapper, as it's never actually
going to be used (we can't *partially* switch to `fastcc`, and this is
only used for Rust functions)
The `noalias` attributes were being set only on function definitions,
not on all declarations. This is harmless for `noalias`, but prevented
some optimization opportunities and is *not* harmless for other
attributes like `sret` with ABI implications.
Closes#9104
In #8185 cross-crate condition handlers were fixed by ensuring that globals
didn't start appearing in different crates with different addressed. An
unfortunate side effect of that pull request is that constants weren't inlined
across crates (uint::bits is unknown to everything but libstd).
This commit fixes this inlining by using the `available_eternally` linkage
provided by LLVM. It partially reverts #8185, and then adds support for this
linkage type. The main caveat is that not all statics could be inlined into
other crates. Before this patch, all statics were considered "inlineable items",
but an unfortunate side effect of how we deal with `&static` and `&[static]`
means that these two cases cannot be inlined across crates. The translation of
constants was modified to propogate this condition of whether a constant
should be considered inlineable into other crates.
Closes#9036
While they may have the same name within various scopes, this changes static
names to use path_pretty_name to append some hash information at the end of the
symbol. We're then guaranteed that each static has a unique NodeId, so this
NodeId is as the "hash" of the pretty name.
Closes#9188
Beforehand it was assumed that the standard cdecl abi was used for all extern
fns of extern crates, but this reads the abi of the extern fn type and declares
the function in the local crate with the appropriate type.
I was trying to think of how to write a test for this, but I was just drawing up blanks :(. Are there standard functions in libc which are not of the cdecl abi? If so we could try linking to them and make sure that the cal completes successfully.
Otherwise, I manually verified that the function was declared correctly by looking at the llvm assembly.
cc #9055 (I'm not sure if this will fix that issue)
Beforehand it was assumed that the standard cdecl abi was used for all extern
fns of extern crates, but this reads the abi of the extern fn type and declares
the function in the local crate with the appropriate type.
Also fixed nasty bug caused by calling LLVMDIBuilderCreateStructType() with a null pointer where an empty array was expected (which would trigger an unintelligable assertion somewhere down the line).
While they may have the same name within various scopes, this changes static
names to use path_pretty_name to append some hash information at the end of the
symbol. We're then guaranteed that each static has a unique NodeId, so this
NodeId is as the "hash" of the pretty name.
Closes#9188
This is a series of patches to modernize option and result. The highlights are:
* rename `.unwrap_or_default(value)` and etc to `.unwrap_or(value)`
* add `.unwrap_or_default()` that uses the `Default` trait
* add `Default` implementations for vecs, HashMap, Option
* add `Option.and(T) -> Option<T>`, `Option.and_then(&fn() -> Option<T>) -> Option<T>`, `Option.or(T) -> Option<T>`, and `Option.or_else(&fn() -> Option<T>) -> Option<T>`
* add `option::ToOption`, `option::IntoOption`, `option::AsOption`, `result::ToResult`, `result::IntoResult`, `result::AsResult`, `either::ToEither`, and `either::IntoEither`, `either::AsEither`
* renamed `Option::chain*` and `Result::chain*` to `and_then` and `or_else` to avoid the eventual collision with `Iterator.chain`.
* Added a bunch of impls of `Default`
* Added a `#[deriving(Default)]` syntax extension
* Removed impls of `Zero` for `Option<T>` and vecs.
Since function pointers do not carry along the function attributes with
them in the type, this needs to be set on the call instruction itself.
Closes#9152
Who would have thought that namespaces are such a can of worms `:P` This is mostly because of some GDB idiosyncrasies (does not use namespace information but linkage-name attributes for displaying items contained in namespaces, also cannot handle functions lexically nested within functions), monomorphization, and information about external items only available from metadata.
This pull request tries to tackle the problem anyway:
* The `DW_AT_linkage_name` for functions is generated just to make GDB display a proper namespace-enabled function name. To this end, a pseudo-mangled name is generated, not corresponding to the real linkage name. This approach shows some success and could be extended to make GDB also show proper parameter types.
* As GDB won't accept subprogram DIEs nested within other subprogram DIEs, the `debuginfo` module now generates a *companion namespace* for each functions (iff needed). A function `fn abc()` will get a companion namespace with name `abc()`, which contains all items (modules, types, functions) declared within the functions scope. The real, proper solution, in my opinion, would be to faithfully reflect the program's lexical structure within DWARF (which allows arbitrary nesting of DIEs, afaik), but I am not sure LLVM's source level debugging implementation would like that and I am pretty sure GDB won't support this in the foreseeable future.
* Monomorphization leads to functions and companion namespaces like `somelib::some_func<int, float>()::some_other_function<bool, bool, bool>()`, which I think is the desired behaviour. There is some design space here, however. Maybe you people prefer `somelib::some_func()::some_other_function<bool, bool, bool>()` or `somelib::some_func()::some_other_function::<int, float, bool, bool, bool>()`.
The solution will work for now but there are a few things on my 'far future wish list':
* A real specification somewhere, what language constructs are mapped to what DWARF structures.
* Proper tests that directly compare the generated DWARF information to the expected results (possibly using something like [pyelftools](https://github.com/eliben/pyelftools) or llvm-dwarfdump)
* A unified implementation for crate-local and crate-external items (which would possibly involve beefing up `ast_map::path` and metadata a bit)
Any comments are welcome!
Closes#1541Closes#1542 (there might be other issues with function name prettiness, but this specific issue should be fixed)
Closes#7715 (source locations for structs and enums are now read correctly from the AST)
