This pull request adds the `rust-gdb` shell script which starts GDB with Rust pretty printers enabled. The PR also makes `rustc` add a special `.debug_gdb_scripts` ELF section on Linux which tells GDB that the produced binary should use the Rust pretty printers.
Note that at the moment this script will only work and be installed on Linux. On Mac OS X there's `rust-lldb` which works much better there. On Windows I had too many problems making this stable. I'll give it another try soonish.
You can use this script just like you would use GDB from the command line. It will use the pretty printers from the Rust "installation" found first in PATH. E.g. if you have `~/rust/x86_64-linux-gnu/stage1/bin` in your path, it will use the pretty printer scripts in `~/rust/x86_64-linux-gnu/stage1/lib/rustlib/etc`.
Rewrite associated types to use projection rather than dummy type parameters. This closes almost every (major) open issue, but I'm holding off on that until the code has landed and baked a bit. Probably it should have more tests, as well, but I wanted to get this landed as fast as possible so that we can collaborate on improving it.
The commit history is a little messy, particularly the merge commit at the end. If I get some time, I might just "reset" to the beginning and try to carve up the final state into logical pieces. Let me know if it seems hard to follow. By far the most crucial commit is "Implement associated type projection and normalization."
r? @nick29581
This commit adds support for the compiler to distinguish between different forms
of lookup paths in the compiler itself. Issue #19767 has some background on this
topic, as well as some sample bugs which can occur if these lookup paths are not
separated.
This commits extends the existing command line flag `-L` with the same trailing
syntax as the `-l` flag. Each argument to `-L` can now have a trailing `:all`,
`:native`, `:crate`, or `:dependency`. This suffix indicates what form of lookup
path the compiler should add the argument to. The `dependency` lookup path is
used when looking up crate dependencies, the `crate` lookup path is used when
looking for immediate dependencies (`extern crate` statements), and the `native`
lookup path is used for probing for native libraries to insert into rlibs. Paths
with `all` are used for all of these purposes (the default).
The default compiler lookup path (the rustlib libdir) is by default added to all
of these paths. Additionally, the `RUST_PATH` lookup path is added to all of
these paths.
Closes#19767
The first six commits are from an earlier PR (#19858) and have already been reviewed. This PR makes an awful hack in the compiler to accommodate slices both natively and in the index a range form. After a snapshot we can hopefully add the new Index impls and then we can remove these awful hacks.
r? @nikomatsakis (or anyone who knows the compiler, really)
This commit performs a second pass for stabilization over the `std::ptr` module.
The specific actions taken were:
* The `RawPtr` trait was renamed to `PtrExt`
* The `RawMutPtr` trait was renamed to `PtrMutExt`
* The module name `ptr` is now stable.
* These functions were all marked `#[stable]` with no modification:
* `null`
* `null_mut`
* `swap`
* `replace`
* `read`
* `write`
* `PtrExt::is_null`
* `PtrExt::is_not_null`
* `PtrExt::offset`
* These functions remain unstable:
* `as_ref`, `as_mut` - the return value of an `Option` is not fully expressive
as null isn't the only bad value, and it's unclear
whether we want to commit to these functions at this
time. The reference/lifetime semantics as written are
also problematic in how they encourage arbitrary
lifetimes.
* `zero_memory` - This function is currently not used at all in the
distribution, and in general it plays a broader role in the
"working with unsafe pointers" story. This story is not yet
fully developed, so at this time the function remains
unstable for now.
* `read_and_zero` - This function remains unstable for largely the same
reasons as `zero_memory`.
* These functions are now all deprecated:
* `PtrExt::null` - call `ptr::null` or `ptr::null_mut` instead.
* `PtrExt::to_uint` - use an `as` expression instead.
All of the current std::sync primitives have poisoning enable which means that
when a task fails inside of a write-access lock then all future attempts to
acquire the lock will fail. This strategy ensures that stale data whose
invariants are possibly not upheld are never viewed by other tasks to help
propagate unexpected panics (bugs in a program) among tasks.
Currently there is no way to test whether a mutex or rwlock is poisoned. One
method would be to duplicate all the methods with a sister foo_catch function,
for example. This pattern is, however, against our [error guidelines][errors].
As a result, this commit exposes the fact that a task has failed internally
through the return value of a `Result`.
[errors]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md#do-not-provide-both-result-and-fail-variants
All methods now return a `LockResult<T>` or a `TryLockResult<T>` which
communicates whether the lock was poisoned or not. In a `LockResult`, both the
`Ok` and `Err` variants contains the `MutexGuard<T>` that is being returned in
order to allow access to the data if poisoning is not desired. This also means
that the lock is *always* held upon returning from `.lock()`.
A new type, `PoisonError`, was added with one method `into_guard` which can
consume the assertion that a lock is poisoned to gain access to the underlying
data.
This is a breaking change because the signatures of these methods have changed,
often incompatible ways. One major difference is that the `wait` methods on a
condition variable now consume the guard and return it in as a `LockResult` to
indicate whether the lock was poisoned while waiting. Most code can be updated
by calling `.unwrap()` on the return value of `.lock()`.
[breaking-change]
[breaking-change]
The `mut` in slices is now redundant. Mutability is 'inferred' from position. This means that if mutability is only obvious from the type, you will need to use explicit calls to the slicing methods.
This commit performs a second pass for stabilization over the `std::ptr` module.
The specific actions taken were:
* The `RawPtr` trait was renamed to `PtrExt`
* The `RawMutPtr` trait was renamed to `MutPtrExt`
* The module name `ptr` is now stable.
* These functions were all marked `#[stable]` with no modification:
* `null`
* `null_mut`
* `swap`
* `replace`
* `read`
* `write`
* `PtrExt::is_null`
* `PtrExt::offset`
* These functions remain unstable:
* `as_ref`, `as_mut` - the return value of an `Option` is not fully expressive
as null isn't the only bad value, and it's unclear
whether we want to commit to these functions at this
time. The reference/lifetime semantics as written are
also problematic in how they encourage arbitrary
lifetimes.
* `zero_memory` - This function is currently not used at all in the
distribution, and in general it plays a broader role in the
"working with unsafe pointers" story. This story is not yet
fully developed, so at this time the function remains
unstable for now.
* `read_and_zero` - This function remains unstable for largely the same
reasons as `zero_memory`.
* These functions are now all deprecated:
* `PtrExt::null` - call `ptr::null` or `ptr::null_mut` instead.
* `PtrExt::to_uint` - use an `as` expression instead.
* `PtrExt::is_not_null` - use `!p.is_null()` instead.
This commit is a second pass stabilization for the `std::comm` module,
performing the following actions:
* The entire `std::comm` module was moved under `std::sync::mpsc`. This movement
reflects that channels are just yet another synchronization primitive, and
they don't necessarily deserve a special place outside of the other
concurrency primitives that the standard library offers.
* The `send` and `recv` methods have all been removed.
* The `send_opt` and `recv_opt` methods have been renamed to `send` and `recv`.
This means that all send/receive operations return a `Result` now indicating
whether the operation was successful or not.
* The error type of `send` is now a `SendError` to implement a custom error
message and allow for `unwrap()`. The error type contains an `into_inner`
method to extract the value.
* The error type of `recv` is now `RecvError` for the same reasons as `send`.
* The `TryRecvError` and `TrySendError` types have had public reexports removed
of their variants and the variant names have been tweaked with enum
namespacing rules.
* The `Messages` iterator is renamed to `Iter`
This functionality is now all `#[stable]`:
* `Sender`
* `SyncSender`
* `Receiver`
* `std::sync::mpsc`
* `channel`
* `sync_channel`
* `Iter`
* `Sender::send`
* `Sender::clone`
* `SyncSender::send`
* `SyncSender::try_send`
* `SyncSender::clone`
* `Receiver::recv`
* `Receiver::try_recv`
* `Receiver::iter`
* `SendError`
* `RecvError`
* `TrySendError::{mod, Full, Disconnected}`
* `TryRecvError::{mod, Empty, Disconnected}`
* `SendError::into_inner`
* `TrySendError::into_inner`
This is a breaking change due to the modification of where this module is
located, as well as the changing of the semantics of `send` and `recv`. Most
programs just need to rename imports of `std::comm` to `std::sync::mpsc` and
add calls to `unwrap` after a send or a receive operation.
[breaking-change]
All of the current std::sync primitives have poisoning enable which means that
when a task fails inside of a write-access lock then all future attempts to
acquire the lock will fail. This strategy ensures that stale data whose
invariants are possibly not upheld are never viewed by other tasks to help
propagate unexpected panics (bugs in a program) among tasks.
Currently there is no way to test whether a mutex or rwlock is poisoned. One
method would be to duplicate all the methods with a sister foo_catch function,
for example. This pattern is, however, against our [error guidelines][errors].
As a result, this commit exposes the fact that a task has failed internally
through the return value of a `Result`.
[errors]: https://github.com/rust-lang/rfcs/blob/master/text/0236-error-conventions.md#do-not-provide-both-result-and-fail-variants
All methods now return a `LockResult<T>` or a `TryLockResult<T>` which
communicates whether the lock was poisoned or not. In a `LockResult`, both the
`Ok` and `Err` variants contains the `MutexGuard<T>` that is being returned in
order to allow access to the data if poisoning is not desired. This also means
that the lock is *always* held upon returning from `.lock()`.
A new type, `PoisonError`, was added with one method `into_guard` which can
consume the assertion that a lock is poisoned to gain access to the underlying
data.
This is a breaking change because the signatures of these methods have changed,
often incompatible ways. One major difference is that the `wait` methods on a
condition variable now consume the guard and return it in as a `LockResult` to
indicate whether the lock was poisoned while waiting. Most code can be updated
by calling `.unwrap()` on the return value of `.lock()`.
[breaking-change]
This commit is an implementation of [RFC 503][rfc] which is a stabilization
story for the prelude. Most of the RFC was directly applied, removing reexports.
Some reexports are kept around, however:
* `range` remains until range syntax has landed to reduce churn.
* `Path` and `GenericPath` remain until path reform lands. This is done to
prevent many imports of `GenericPath` which will soon be removed.
* All `io` traits remain until I/O reform lands so imports can be rewritten all
at once to `std::io::prelude::*`.
This is a breaking change because many prelude reexports have been removed, and
the RFC can be consulted for the exact list of removed reexports, as well as to
find the locations of where to import them.
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0503-prelude-stabilization.md
[breaking-change]
Closes#20068
More work on opt-in built in traits. `Send` and `Sync` are not opt-in, `OwnedPtr` renamed to `UniquePtr` and the `Send` and `Sync` traits are now unsafe.
NOTE: This likely needs to be rebased on top of the yet-to-land snapshot.
r? @nikomatsakis
cc #13231
Various refactorings simplifying the mem-categorization and regionck interface. This is working towards an improvement for closure-and-upvar-mode inference.
r? @eddyb
There is also some work here to make resolve a bit more stable - it no longer overwrites a specific import with a glob import.
[breaking-change]
Import shadowing of single/list imports by globs is now forbidden. An interesting case is where a glob import imports a re-export (`pub use`) of a single import. This still counts as a single import for the purposes of shadowing .You can usually fix any bustage by re-ordering such imports. A single import may still shadow (override) a glob import or the prelude.
... really this time `:)`
I went for the simpler fix after all since it turned out to become a bit too complicated to extract the current iteration value from its containing `Option` with the different memory layouts it can have. It's also what we already do for match bindings.
I also extended the new test case to include the "simple identifier" case.
Fixes#20127, fixes#19732
The previous behaviour of using the smallest type possible caused LLVM
to treat padding too conservatively, causing poor codegen. This commit
changes the behaviour to use an alignment-sized integer as the
discriminant. This keeps types the same size, but helps LLVM understand
the data structure a little better, resulting in better codegen.
This commit adds support for the compiler to distinguish between different forms
of lookup paths in the compiler itself. Issue #19767 has some background on this
topic, as well as some sample bugs which can occur if these lookup paths are not
separated.
This commits extends the existing command line flag `-L` with the same trailing
syntax as the `-l` flag. Each argument to `-L` can now have a trailing `:all`,
`:native`, `:crate`, or `:dependency`. This suffix indicates what form of lookup
path the compiler should add the argument to. The `dependency` lookup path is
used when looking up crate dependencies, the `crate` lookup path is used when
looking for immediate dependencies (`extern crate` statements), and the `native`
lookup path is used for probing for native libraries to insert into rlibs. Paths
with `all` are used for all of these purposes (the default).
The default compiler lookup path (the rustlib libdir) is by default added to all
of these paths. Additionally, the `RUST_PATH` lookup path is added to all of
these paths.
Closes#19767
The previous behaviour of using the smallest type possible caused LLVM
to treat padding too conservatively, causing poor codegen. This commit
changes the behaviour to use an type-alignment-sized integer as the
discriminant. This keeps types the same size, but helps LLVM understand
the data structure a little better, resulting in better codegen.
post-unboxed-closure-conversion. This requires a fair amount of
annoying coercions because all the `map` etc types are defined
generically over the `F`, so the automatic coercions don't propagate;
this is compounded by the need to use `let` and not `as` due to
stage0. That said, this pattern is to a large extent temporary and
unusual.
Back when for-loop iteration variables were just de-sugared into `let` bindings, debuginfo for them was created like for any other `let` binding. When the implementation approach for for-loops changed, we ceased having debuginfo for the iteration variable. This PR fixes this omission and adds a more prominent test case for it.
Also contains some minor, general cleanup of the debuginfo module.
Fixes#19732
#16081 fixed an issue where a nested return statement would cause incorrect behaviour due to the inner return writing over the return stack slot that had already been written too. However, the check was very broad and picked many cases that wouldn't ever be affected by this issue.
As a result, the number of allocas increased dramatically and therefore stack-size increased. LLVM is not able to remove all of the extraneous allocas. Any code that had multiple return values in a compound expression at the end of a function (including loops) would be hit by the issue.
The check now uses a control-flow graph to only consider the case when the inner return is executed conditionally. By itself, this narrowed definition causes #15763 to return, so the control-flow graph is also used to avoid passing the return slot as a destination when the result won't be used.
This change allows the stack-size of the main rustc task to be reduced to 8MB from 32MB.
This commit shuffles around some CLI flags of the compiler to some more stable
locations with some renamings. The changes made were:
* The `-v` flag has been repurposes as the "verbose" flag. The version flag has
been renamed to `-V`.
* The `-h` screen has been split into two parts. Most top-level options (not
all) show with `-h`, and the remaining options (generally obscure) can be
shown with `--help -v` which is a "verbose help screen"
* The `-V` flag (version flag now) has lost its argument as it is now requested
with `rustc -vV` "verbose version".
* The `--emit` option has had its `ir` and `bc` variants renamed to `llvm-ir`
and `llvm-bc` to emphasize that they are LLVM's IR/bytecode.
* The `--emit` option has grown a new variant, `dep-info`, which subsumes the
`--dep-info` CLI argument. The `--dep-info` flag is now deprecated.
* The `--parse-only`, `--no-trans`, `--no-analysis`, and `--pretty` flags have
moved behind the `-Z` family of flags.
* The `--debuginfo` and `--opt-level` flags were moved behind the top-level `-C`
flag.
* The `--print-file-name` and `--print-crate-name` flags were moved behind one
global `--print` flag which now accepts one of `crate-name`, `file-names`, or
`sysroot`. This global `--print` flag is intended to serve as a mechanism for
learning various metadata about the compiler itself.
* The top-level `--pretty` flag was moved to a number of `-Z` options.
No warnings are currently enabled to allow tools like Cargo to have time to
migrate to the new flags before spraying warnings to all users.
cc https://github.com/rust-lang/rust/issues/19051
This commit shuffles around some CLI flags of the compiler to some more stable
locations with some renamings. The changes made were:
* The `-v` flag has been repurposes as the "verbose" flag. The version flag has
been renamed to `-V`.
* The `-h` screen has been split into two parts. Most top-level options (not
all) show with `-h`, and the remaining options (generally obscure) can be
shown with `--help -v` which is a "verbose help screen"
* The `-V` flag (version flag now) has lost its argument as it is now requested
with `rustc -vV` "verbose version".
* The `--emit` option has had its `ir` and `bc` variants renamed to `llvm-ir`
and `llvm-bc` to emphasize that they are LLVM's IR/bytecode.
* The `--emit` option has grown a new variant, `dep-info`, which subsumes the
`--dep-info` CLI argument. The `--dep-info` flag is now deprecated.
* The `--parse-only`, `--no-trans`, and `--no-analysis` flags have
moved behind the `-Z` family of flags.
* The `--debuginfo` and `--opt-level` flags were moved behind the top-level `-C`
flag.
* The `--print-file-name` and `--print-crate-name` flags were moved behind one
global `--print` flag which now accepts one of `crate-name`, `file-names`, or
`sysroot`. This global `--print` flag is intended to serve as a mechanism for
learning various metadata about the compiler itself.
No warnings are currently enabled to allow tools like Cargo to have time to
migrate to the new flags before spraying warnings to all users.
Rewrite how the HRTB algorithm matches impls against obligations. Instead of impls providing higher-ranked trait-references, impls now once again only have early-bound regions. The skolemization checks are thus moved out into trait matching itself. This allows to implement "perfect forwarding" impls like those described in #19730. This PR builds on a previous PR that was already reviewed by @pnkfelix.
r? @pnkfelix
Fixes#19730
This PR substantially narrows the notion of a "runtime" in Rust, and allows calling into Rust code directly without any setup or teardown.
After this PR, the basic "runtime support" in Rust will consist of:
* Unwinding and backtrace support
* Stack guards
Other support, such as helper threads for timers or the notion of a "current thread" are initialized automatically upon first use.
When using Rust in an embedded context, it should now be possible to call a Rust function directly as a C function with absolutely no setup, though in that case panics will cause the process to abort. In this regard, the C/Rust interface will look much like the C/C++ interface.
In more detail, this PR:
* Merges `librustrt` back into `std::rt`, undoing the facade. While doing so, it removes a substantial amount of redundant functionality (such as mutexes defined in the `rt` module). Code using `librustrt` can now call into `std::rt` to e.g. start executing Rust code with unwinding support.
* Allows all runtime data to be initialized lazily, including the "current thread", the "at_exit" infrastructure, and the "args" storage.
* Deprecates and largely removes `std::task` along with the widespread requirement that there be a "current task" for many APIs in `std`. The entire task infrastructure is replaced with `std::thread`, which provides a more standard API for manipulating and creating native OS threads. In particular, it's possible to join on a created thread, and to get a handle to the currently-running thread. In addition, threads are equipped with some basic blocking support in the form of `park`/`unpark` operations (following a tradition in some OSes as well as the JVM). See the `std::thread` documentation for more details.
* Channels are refactored to use a new internal blocking infrastructure that itself sits on top of `park`/`unpark`.
One important change here is that a Rust program ends when its main thread does, following most threading models. On the other hand, threads will often be created with an RAII-style join handle that will re-institute blocking semantics naturally (and with finer control).
This is very much a:
[breaking-change]
Closes#18000
r? @alexcrichton
This commit is part of a series that introduces a `std::thread` API to
replace `std::task`.
In the new API, `spawn` returns a `JoinGuard`, which by default will
join the spawned thread when dropped. It can also be used to join
explicitly at any time, returning the thread's result. Alternatively,
the spawned thread can be explicitly detached (so no join takes place).
As part of this change, Rust processes now terminate when the main
thread exits, even if other detached threads are still running, moving
Rust closer to standard threading models. This new behavior may break code
that was relying on the previously implicit join-all.
In addition to the above, the new thread API also offers some built-in
support for building blocking abstractions in user space; see the module
doc for details.
Closes#18000
[breaking-change]
followed by a semicolon.
This allows code like `vec![1i, 2, 3].len();` to work.
This breaks code that uses macros as statements without putting
semicolons after them, such as:
fn main() {
...
assert!(a == b)
assert!(c == d)
println(...);
}
It also breaks code that uses macros as items without semicolons:
local_data_key!(foo)
fn main() {
println("hello world")
}
Add semicolons to fix this code. Those two examples can be fixed as
follows:
fn main() {
...
assert!(a == b);
assert!(c == d);
println(...);
}
local_data_key!(foo);
fn main() {
println("hello world")
}
RFC #378.
Closes#18635.
[breaking-change]
This narrows the definition of nested returns such that only when the
outer return has a chance of being executed (due to the inner return
being conditional) do we mark the function as having nested returns.
Fixes#19684
per rfc 459
cc https://github.com/rust-lang/rust/issues/19390
One question is: should we start by warning, and only switch to hard error later? I think we discussed something like this in the meeting.
r? @alexcrichton
- The following operator traits now take their arguments by value: `Add`, `Sub`, `Mul`, `Div`, `Rem`, `BitAnd`, `BitOr`, `BitXor`, `Shl`, `Shr`. This breaks all existing implementations of these traits.
- The binary operation `a OP b` now "desugars" to `OpTrait::op_method(a, b)` and consumes both arguments.
- `String` and `Vec` addition have been changed to reuse the LHS owned value, and to avoid internal cloning. Only the following asymmetric operations are available: `String + &str` and `Vec<T> + &[T]`, which are now a short-hand for the "append" operation.
[breaking-change]
---
This passes `make check` locally. I haven't touch the unary operators in this PR, but converting them to by value should be very similar to this PR. I can work on them after this gets the thumbs up.
@nikomatsakis r? the compiler changes
@aturon r? the library changes. I think the only controversial bit is the semantic change of the `Vec`/`String` `Add` implementation.
cc #19148
On AArch64, libc::c_char is u8. There are some places in the code where i8 is assumed, which causes compilation errors.
(AArch64 is not officially supported yet, but this change does not hurt any other targets and makes the code future-proof.)
This patch does not itself enable generalized where clauses, but it lays the groundwork. Rather than storing a list of bounds per type parameter, the trait selection and other logic is now driven by a unified list of predicates. All predicate handling is now driven through a common interface. This also fixes a number of bugs where region predicates were being dropped on the floor. As a drive-by, this patch also fixes some bugs in the opt-out-copy feature flag.
That said, this patch does not change the parser or AST in any way, so we still *generate* the list of predicates by walking a list of bounds (and we still *store* the bounds on the `TypeParameterDef` and so on). Those will get patched in a follow-up.
The commits in this case are standalone; the first few are simple refactorings.
r? @nick29581
cc @aturon
in most cases, just the error message changed, but in some cases we
are reporting new errors that OUGHT to have been reported before but
we're overlooked (mostly involving the `'static` bound on `Send`).
These probably happened during the merge of the commit that made `Copy` opt-in.
Also, convert the last occurence of `/**` to `///` in `src/libstd/num/strconv.rs`
This detects (a subset of) the cases when `transmute::<T, U>(x)` can be
lowered to a direct `bitcast T x to U` in LLVM. This assists with
efficiently handling a SIMD vector as multiple different types,
e.g. swapping bytes/words/double words around inside some larger vector
type.
C compilers like GCC and Clang handle integer vector types as `__m128i`
for all widths, and implicitly insert bitcasts as required. This patch
allows Rust to express this, even if it takes a bit of `unsafe`, whereas
previously it was impossible to do at all without inline assembly.
Example:
pub fn reverse_u32s(u: u64x2) -> u64x2 {
unsafe {
let tmp = mem::transmute::<_, u32x4>(u);
let swapped = u32x4(tmp.3, tmp.2, tmp.1, tmp.0);
mem::transmute::<_, u64x2>(swapped)
}
}
Compiling with `--opt-level=3` gives:
Before
define <2 x i64> @_ZN12reverse_u32s20hbdb206aba18a03d8tbaE(<2 x i64>) unnamed_addr #0 {
entry-block:
%1 = bitcast <2 x i64> %0 to i128
%u.0.extract.trunc = trunc i128 %1 to i32
%u.4.extract.shift = lshr i128 %1, 32
%u.4.extract.trunc = trunc i128 %u.4.extract.shift to i32
%u.8.extract.shift = lshr i128 %1, 64
%u.8.extract.trunc = trunc i128 %u.8.extract.shift to i32
%u.12.extract.shift = lshr i128 %1, 96
%u.12.extract.trunc = trunc i128 %u.12.extract.shift to i32
%2 = insertelement <4 x i32> undef, i32 %u.12.extract.trunc, i64 0
%3 = insertelement <4 x i32> %2, i32 %u.8.extract.trunc, i64 1
%4 = insertelement <4 x i32> %3, i32 %u.4.extract.trunc, i64 2
%5 = insertelement <4 x i32> %4, i32 %u.0.extract.trunc, i64 3
%6 = bitcast <4 x i32> %5 to <2 x i64>
ret <2 x i64> %6
}
_ZN12reverse_u32s20hbdb206aba18a03d8tbaE:
.cfi_startproc
movd %xmm0, %rax
punpckhqdq %xmm0, %xmm0
movd %xmm0, %rcx
movq %rcx, %rdx
shrq $32, %rdx
movq %rax, %rsi
shrq $32, %rsi
movd %eax, %xmm0
movd %ecx, %xmm1
punpckldq %xmm0, %xmm1
movd %esi, %xmm2
movd %edx, %xmm0
punpckldq %xmm2, %xmm0
punpckldq %xmm1, %xmm0
retq
After
define <2 x i64> @_ZN12reverse_u32s20hbdb206aba18a03d8tbaE(<2 x i64>) unnamed_addr #0 {
entry-block:
%1 = bitcast <2 x i64> %0 to <4 x i32>
%2 = shufflevector <4 x i32> %1, <4 x i32> undef, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
%3 = bitcast <4 x i32> %2 to <2 x i64>
ret <2 x i64> %3
}
_ZN12reverse_u32s20hbdb206aba18a03d8tbaE:
.cfi_startproc
pshufd $27, %xmm0, %xmm0
retq
These probably happened during the merge of the commit that made `Copy` opt-in.
Also, convert the last occurence of `/**` to `///` in `src/libstd/num/strconv.rs`
This change makes the compiler no longer infer whether types (structures
and enumerations) implement the `Copy` trait (and thus are implicitly
copyable). Rather, you must implement `Copy` yourself via `impl Copy for
MyType {}`.
A new warning has been added, `missing_copy_implementations`, to warn
you if a non-generic public type has been added that could have
implemented `Copy` but didn't.
For convenience, you may *temporarily* opt out of this behavior by using
`#![feature(opt_out_copy)]`. Note though that this feature gate will never be
accepted and will be removed by the time that 1.0 is released, so you should
transition your code away from using it.
This breaks code like:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
Change this code to:
#[deriving(Show)]
struct Point2D {
x: int,
y: int,
}
impl Copy for Point2D {}
fn main() {
let mypoint = Point2D {
x: 1,
y: 1,
};
let otherpoint = mypoint;
println!("{}{}", mypoint, otherpoint);
}
This is the backwards-incompatible part of #13231.
Part of RFC #3.
[breaking-change]
Now that we have an overloaded comparison (`==`) operator, and that `Vec`/`String` deref to `[T]`/`str` on method calls, many `as_slice()`/`as_mut_slice()`/`to_string()` calls have become redundant. This patch removes them. These were the most common patterns:
- `assert_eq(test_output.as_slice(), "ground truth")` -> `assert_eq(test_output, "ground truth")`
- `assert_eq(test_output, "ground truth".to_string())` -> `assert_eq(test_output, "ground truth")`
- `vec.as_mut_slice().sort()` -> `vec.sort()`
- `vec.as_slice().slice(from, to)` -> `vec.slice(from_to)`
---
Note that e.g. `a_string.push_str(b_string.as_slice())` has been left untouched in this PR, since we first need to settle down whether we want to favor the `&*b_string` or the `b_string[]` notation.
This is rebased on top of #19167
cc @alexcrichton @aturon
In regards to:
https://github.com/rust-lang/rust/issues/19253#issuecomment-64836729
This commit:
* Changes the #deriving code so that it generates code that utilizes fewer
reexports (in particur Option::* and Result::*), which is necessary to
remove those reexports in the future
* Changes other areas of the codebase so that fewer reexports are utilized
Comparison traits have gained an `Rhs` input parameter that defaults to `Self`. And now the comparison operators can be overloaded to work between different types. In particular, this PR allows the following operations (and their commutative versions):
- `&str` == `String` == `CowString`
- `&[A]` == `&mut [B]` == `Vec<C>` == `CowVec<D>` == `[E, ..N]` (for `N` up to 32)
- `&mut A` == `&B` (for `Sized` `A` and `B`)
Where `A`, `B`, `C`, `D`, `E` may be different types that implement `PartialEq`. For example, these comparisons are now valid: `string == "foo"`, and `vec_of_strings == ["Hello", "world"]`.
[breaking-change]s
Since the `==` may now work on different types, operations that relied on the old "same type restriction" to drive type inference, will need to be type annotated. These are the most common fallout cases:
- `some_vec == some_iter.collect()`: `collect` needs to be type annotated: `collect::<Vec<_>>()`
- `slice == &[a, b, c]`: RHS doesn't get coerced to an slice, use an array instead `[a, b, c]`
- `lhs == []`: Change expression to `lhs.is_empty()`
- `lhs == some_generic_function()`: Type annotate the RHS as necessary
cc #19148
r? @aturon
This detects (a subset of) the cases when `transmute::<T, U>(x)` can be
lowered to a direct `bitcast T x to U` in LLVM. This assists with
efficiently handling a SIMD vector as multiple different types,
e.g. swapping bytes/words/double words around inside some larger vector
type.
C compilers like GCC and Clang handle integer vector types as `__m128i`
for all widths, and implicitly insert bitcasts as required. This patch
allows Rust to express this, even if it takes a bit of `unsafe`, whereas
previously it was impossible to do at all without inline assembly.
Example:
pub fn reverse_u32s(u: u64x2) -> u64x2 {
unsafe {
let tmp = mem::transmute::<_, u32x4>(u);
let swapped = u32x4(tmp.3, tmp.2, tmp.1, tmp.0);
mem::transmute::<_, u64x2>(swapped)
}
}
Compiling with `--opt-level=3` gives:
Before
define <2 x i64> @_ZN12reverse_u32s20hbdb206aba18a03d8tbaE(<2 x i64>) unnamed_addr #0 {
entry-block:
%1 = bitcast <2 x i64> %0 to i128
%u.0.extract.trunc = trunc i128 %1 to i32
%u.4.extract.shift = lshr i128 %1, 32
%u.4.extract.trunc = trunc i128 %u.4.extract.shift to i32
%u.8.extract.shift = lshr i128 %1, 64
%u.8.extract.trunc = trunc i128 %u.8.extract.shift to i32
%u.12.extract.shift = lshr i128 %1, 96
%u.12.extract.trunc = trunc i128 %u.12.extract.shift to i32
%2 = insertelement <4 x i32> undef, i32 %u.12.extract.trunc, i64 0
%3 = insertelement <4 x i32> %2, i32 %u.8.extract.trunc, i64 1
%4 = insertelement <4 x i32> %3, i32 %u.4.extract.trunc, i64 2
%5 = insertelement <4 x i32> %4, i32 %u.0.extract.trunc, i64 3
%6 = bitcast <4 x i32> %5 to <2 x i64>
ret <2 x i64> %6
}
_ZN12reverse_u32s20hbdb206aba18a03d8tbaE:
.cfi_startproc
movd %xmm0, %rax
punpckhqdq %xmm0, %xmm0
movd %xmm0, %rcx
movq %rcx, %rdx
shrq $32, %rdx
movq %rax, %rsi
shrq $32, %rsi
movd %eax, %xmm0
movd %ecx, %xmm1
punpckldq %xmm0, %xmm1
movd %esi, %xmm2
movd %edx, %xmm0
punpckldq %xmm2, %xmm0
punpckldq %xmm1, %xmm0
retq
After
define <2 x i64> @_ZN12reverse_u32s20hbdb206aba18a03d8tbaE(<2 x i64>) unnamed_addr #0 {
entry-block:
%1 = bitcast <2 x i64> %0 to <4 x i32>
%2 = shufflevector <4 x i32> %1, <4 x i32> undef, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
%3 = bitcast <4 x i32> %2 to <2 x i64>
ret <2 x i64> %3
}
_ZN12reverse_u32s20hbdb206aba18a03d8tbaE:
.cfi_startproc
pshufd $27, %xmm0, %xmm0
retq
One negative side-effect of this change is that there might be quite a bit of copying strings out of the codemap, i.e. one copy for every block that gets translated, just for taking a look at the last character of the block. If this turns out to cause a performance problem then `CodeMap::span_to_snippet()` could be changed return `Option<&str>` instead of `Option<String>`.
Fixes#18791
Implements RFC 438.
Fixes#19092.
This is a [breaking-change]: change types like `&Foo+Send` or `&'a mut Foo+'a` to `&(Foo+Send)` and `&'a mut (Foo+'a)`, respectively.
r? @brson
This PR adds the `rust-lldb` script (feel free to bikeshed about the name).
The script will start LLDB and, before doing anything else, load [LLDB type summaries](http://lldb.llvm.org/varformats.html) that will make LLDB print values with Rust syntax. Just use the script like you would normally use LLDB:
```
rust-lldb executable-to-debug --and-any-other-commandline --args
```
The script will just add one additional commandline argument to the LLDB invocation and pass along the rest of the arguments to LLDB after that.
Given the following program...
```rust
fn main() {
let x = Some(1u);
let y = [0, 1, 2i];
let z = (x, y);
println!("{} {} {}", x, y, z);
}
```
...*without* the 'LLDB type summaries', values will be printed something like this...
```
(lldb) p x
(core::option::Option<uint>) $3 = {
= (RUST$ENUM$DISR = Some)
= (RUST$ENUM$DISR = Some, 1)
}
(lldb) p y
(long [3]) $4 = ([0] = 0, [1] = 1, [2] = 2)
(lldb) p z
((core::option::Option<uint>, [int, ..3])) $5 = {
= {
= (RUST$ENUM$DISR = Some)
= (RUST$ENUM$DISR = Some, 1)
}
= ([0] = 0, [1] = 1, [2] = 2)
}
```
...*with* the 'LLDB type summaries', values will be printed like this:
```
(lldb) p x
(core::option::Option<uint>) $0 = Some(1)
(lldb) p y
(long [3]) $1 = [0, 1, 2]
(lldb) p z
((core::option::Option<uint>, [int, ..3])) $2 = (Some(1), [0, 1, 2])
```
The 'LLDB type summaries' used by the script have been in use for a while in the LLDB autotests but I still consider them to be of alpha-version quality. If you see anything weird when you use them, feel free to file an issue.
The script will use whatever Rust "installation" is in PATH, so whichever `rustc` will be called if you type `rustc` into the console, this is the one that the script will ask for the LLDB extension module location. The build system will take care of putting the script and LLDB python module in the right places, whether you want to use the stage1 or stage2 compiler or the one coming with `make install` / `rustup.sh`.
Since I don't have much experience with the build system, Makefiles and shell scripts, please look these changes over carefully.
Code to fragment paths into pieces based on subparts being moved around, e.g. moving `x.1` out of a tuple `(A,B,C)` leaves behind the fragments `x.0: A` and `x.2: C`. Further discussion in borrowck/doc.rs.
Includes differentiation between assigned_fragments and moved_fragments, support for all-but-one array fragments, and instrumentation to print out the moved/assigned/unmmoved/parents for each function, factored out into a separate submodule.
These fragments can then be used by `trans` to inject stack-local dynamic drop flags. (They also can be hooked up with dataflow to reduce the expected number of injected flags.)
This is accomplished by:
1. Add `MatchMode` enum to `expr_use_visitor`.
2. Computing the match mode for each pattern via a pre-pass, and then
passing the mode along when visiting the pattern in
expr_use_visitor.
3. Adding a `fn matched_pat` callback to expr_use_visitor, which is
called on interior struct and enum nodes of the pattern (as opposed
to `fn consume_pat`, which is only invoked for identifiers at the
leaves of the pattern), and invoking it accordingly.
Of particular interest are the `cat_downcast` instances established
when matching enum variants.
This change applies the conventions to unwrap listed in [RFC 430][rfc] to rename
non-failing `unwrap` methods to `into_inner`. This is a breaking change, but all
`unwrap` methods are retained as `#[deprecated]` for the near future. To update
code rename `unwrap` method calls to `into_inner`.
[rfc]: https://github.com/rust-lang/rfcs/pull/430
[breaking-change]
cc #19091
This commit removes the `std::local_data` module in favor of a new
`std::thread_local` module providing thread local storage. The module provides
two variants of TLS: one which owns its contents and one which is based on
scoped references. Each implementation has pros and cons listed in the
documentation.
Both flavors have accessors through a function called `with` which yield a
reference to a closure provided. Both flavors also panic if a reference cannot
be yielded and provide a function to test whether an access would panic or not.
This is an implementation of [RFC 461][rfc] and full details can be found in
that RFC.
This is a breaking change due to the removal of the `std::local_data` module.
All users can migrate to the new thread local system like so:
thread_local!(static FOO: Rc<RefCell<Option<T>>> = Rc::new(RefCell::new(None)))
The old `local_data` module inherently contained the `Rc<RefCell<Option<T>>>` as
an implementation detail which must now be explicitly stated by users.
[rfc]: https://github.com/rust-lang/rfcs/pull/461
[breaking-change]
This change applies the conventions to unwrap listed in [RFC 430][rfc] to rename
non-failing `unwrap` methods to `into_inner`. This is a breaking change, but all
`unwrap` methods are retained as `#[deprecated]` for the near future. To update
code rename `unwrap` method calls to `into_inner`.
[rfc]: https://github.com/rust-lang/rfcs/pull/430
[breaking-change]
Closes#13159
cc #19091
This breaks code like
```
let t = (42i, 42i);
... t.0::<int> ...;
```
Change this code to not contain an unused type parameter. For example:
```
let t = (42i, 42i);
... t.0 ...;
```
Closes https://github.com/rust-lang/rust/issues/19096
[breaking-change]
r? @aturon
The struct_variant is not gated anymore. This commit just removes it and the resulting warnings when compiling rust. Now compiles with the snapshot from 11/18 (as opposed to PR #19014)
(Previously, scopes were solely identified with NodeId's; this
refactoring prepares for a future where that does not hold.)
Ground work for a proper fix to #8861.
(Previously, statically identifiable scopes/regions were solely
identified with NodeId's; this refactoring prepares for a future
where that 1:1 correspondence does not hold.)
Use the expected type to infer the argument/return types of unboxed closures. Also, in `||` expressions, use the expected type to decide if the result should be a boxed or unboxed closure (and if an unboxed closure, what kind).
This supercedes PR #19089, which was already reviewed by @pcwalton.
This commit applies the stabilization of std::fmt as outlined in [RFC 380][rfc].
There are a number of breaking changes as a part of this commit which will need
to be handled to migrated old code:
* A number of formatting traits have been removed: String, Bool, Char, Unsigned,
Signed, and Float. It is recommended to instead use Show wherever possible or
to use adaptor structs to implement other methods of formatting.
* The format specifier for Boolean has changed from `t` to `b`.
* The enum `FormatError` has been renamed to `Error` as well as becoming a unit
struct instead of an enum. The `WriteError` variant no longer exists.
* The `format_args_method!` macro has been removed with no replacement. Alter
code to use the `format_args!` macro instead.
* The public fields of a `Formatter` have become read-only with no replacement.
Use a new formatting string to alter the formatting flags in combination with
the `write!` macro. The fields can be accessed through accessor methods on the
`Formatter` structure.
Other than these breaking changes, the contents of std::fmt should now also all
contain stability markers. Most of them are still #[unstable] or #[experimental]
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0380-stabilize-std-fmt.md
[breaking-change]
Closes#18904
This commit applies the stabilization of std::fmt as outlined in [RFC 380][rfc].
There are a number of breaking changes as a part of this commit which will need
to be handled to migrated old code:
* A number of formatting traits have been removed: String, Bool, Char, Unsigned,
Signed, and Float. It is recommended to instead use Show wherever possible or
to use adaptor structs to implement other methods of formatting.
* The format specifier for Boolean has changed from `t` to `b`.
* The enum `FormatError` has been renamed to `Error` as well as becoming a unit
struct instead of an enum. The `WriteError` variant no longer exists.
* The `format_args_method!` macro has been removed with no replacement. Alter
code to use the `format_args!` macro instead.
* The public fields of a `Formatter` have become read-only with no replacement.
Use a new formatting string to alter the formatting flags in combination with
the `write!` macro. The fields can be accessed through accessor methods on the
`Formatter` structure.
Other than these breaking changes, the contents of std::fmt should now also all
contain stability markers. Most of them are still #[unstable] or #[experimental]
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/0380-stabilize-std-fmt.md
[breaking-change]
Closes#18904
region binding at the impl site, so for method types that come from impls,
it is necessary to liberate/instantiate late-bound regions at multiple
depths.
