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Unrolled build for rust-lang#121598
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Rollup merge of rust-lang#121598 - RalfJung:catch_unwind, r=oli-obk

rename 'try' intrinsic to 'catch_unwind'

The intrinsic has nothing to do with `try` blocks, and corresponds to the stable `catch_unwind` function, so this makes a lot more sense IMO.

Also rename Miri's special function while we are at it, to reflect the level of abstraction it works on: it's an unwinding mechanism, on which Rust implements panics.
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rust-timer authored Feb 27, 2024
2 parents 5c786a7 + a3c0f3a commit c034dd6
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Showing 24 changed files with 67 additions and 55 deletions.
4 changes: 2 additions & 2 deletions compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -23,7 +23,7 @@ use rustc_middle::ty::layout::{HasParamEnv, ValidityRequirement};
use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
use rustc_middle::ty::GenericArgsRef;
use rustc_span::source_map::Spanned;
use rustc_span::symbol::{kw, sym, Symbol};
use rustc_span::symbol::{sym, Symbol};

pub(crate) use self::llvm::codegen_llvm_intrinsic_call;
use crate::prelude::*;
Expand Down Expand Up @@ -1132,7 +1132,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
ret.write_cvalue(fx, val);
}

kw::Try => {
sym::catch_unwind => {
intrinsic_args!(fx, args => (f, data, catch_fn); intrinsic);
let f = f.load_scalar(fx);
let data = data.load_scalar(fx);
Expand Down
4 changes: 2 additions & 2 deletions compiler/rustc_codegen_gcc/src/intrinsic/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ use rustc_middle::ty::{self, Instance, Ty};
use rustc_middle::ty::layout::LayoutOf;
#[cfg(feature="master")]
use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
use rustc_span::{Span, Symbol, symbol::kw, sym};
use rustc_span::{Span, Symbol, sym};
use rustc_target::abi::HasDataLayout;
use rustc_target::abi::call::{ArgAbi, FnAbi, PassMode};
use rustc_target::spec::PanicStrategy;
Expand Down Expand Up @@ -129,7 +129,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
let res = self.context.new_call(None, builtin, &[a]);
self.icmp(IntPredicate::IntEQ, res, self.const_i32(0))
}
kw::Try => {
sym::catch_unwind => {
try_intrinsic(
self,
args[0].immediate(),
Expand Down
8 changes: 4 additions & 4 deletions compiler/rustc_codegen_llvm/src/intrinsic.rs
Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,7 @@ use rustc_hir as hir;
use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf};
use rustc_middle::ty::{self, GenericArgsRef, Ty};
use rustc_middle::{bug, span_bug};
use rustc_span::{sym, symbol::kw, Span, Symbol};
use rustc_span::{sym, Span, Symbol};
use rustc_target::abi::{self, Align, HasDataLayout, Primitive};
use rustc_target::spec::{HasTargetSpec, PanicStrategy};

Expand Down Expand Up @@ -133,8 +133,8 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> {
}
sym::unlikely => self
.call_intrinsic("llvm.expect.i1", &[args[0].immediate(), self.const_bool(false)]),
kw::Try => {
try_intrinsic(
sym::catch_unwind => {
catch_unwind_intrinsic(
self,
args[0].immediate(),
args[1].immediate(),
Expand Down Expand Up @@ -457,7 +457,7 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> {
}
}

fn try_intrinsic<'ll>(
fn catch_unwind_intrinsic<'ll>(
bx: &mut Builder<'_, 'll, '_>,
try_func: &'ll Value,
data: &'ll Value,
Expand Down
4 changes: 2 additions & 2 deletions compiler/rustc_hir_analysis/src/check/intrinsic.rs
Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@ use rustc_hir as hir;
use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
use rustc_middle::ty::{self, Ty, TyCtxt};
use rustc_span::def_id::LocalDefId;
use rustc_span::symbol::{kw, sym};
use rustc_span::symbol::sym;
use rustc_span::{Span, Symbol};
use rustc_target::spec::abi::Abi;

Expand Down Expand Up @@ -445,7 +445,7 @@ pub fn check_intrinsic_type(
)
}

kw::Try => {
sym::catch_unwind => {
let mut_u8 = Ty::new_mut_ptr(tcx, tcx.types.u8);
let try_fn_ty = ty::Binder::dummy(tcx.mk_fn_sig(
[mut_u8],
Expand Down
1 change: 1 addition & 0 deletions compiler/rustc_span/src/symbol.rs
Original file line number Diff line number Diff line change
Expand Up @@ -487,6 +487,7 @@ symbols! {
call_once,
caller_location,
capture_disjoint_fields,
catch_unwind,
cause,
cdylib,
ceilf32,
Expand Down
25 changes: 18 additions & 7 deletions library/core/src/intrinsics.rs
Original file line number Diff line number Diff line change
Expand Up @@ -75,6 +75,9 @@ pub unsafe fn drop_in_place<T: ?Sized>(to_drop: *mut T) {
unsafe { crate::ptr::drop_in_place(to_drop) }
}

#[cfg(bootstrap)]
pub use self::r#try as catch_unwind;

extern "rust-intrinsic" {
// N.B., these intrinsics take raw pointers because they mutate aliased
// memory, which is not valid for either `&` or `&mut`.
Expand Down Expand Up @@ -2382,16 +2385,24 @@ extern "rust-intrinsic" {
#[rustc_nounwind]
pub fn variant_count<T>() -> usize;

/// Rust's "try catch" construct which invokes the function pointer `try_fn`
/// with the data pointer `data`.
///
/// The third argument is a function called if a panic occurs. This function
/// takes the data pointer and a pointer to the target-specific exception
/// object that was caught. For more information see the compiler's
/// source as well as std's catch implementation.
/// Rust's "try catch" construct for unwinding. Invokes the function pointer `try_fn` with the
/// data pointer `data`, and calls `catch_fn` if unwinding occurs while `try_fn` runs.
///
/// `catch_fn` must not unwind.
///
/// The third argument is a function called if an unwind occurs (both Rust unwinds and foreign
/// unwinds). This function takes the data pointer and a pointer to the target-specific
/// exception object that was caught. For more information, see the compiler's source as well as
/// std's `catch_unwind` implementation.
///
/// The stable version of this intrinsic is `std::panic::catch_unwind`.
#[rustc_nounwind]
#[cfg(not(bootstrap))]
pub fn catch_unwind(try_fn: fn(*mut u8), data: *mut u8, catch_fn: fn(*mut u8, *mut u8)) -> i32;

/// For bootstrap only, see `catch_unwind`.
#[rustc_nounwind]
#[cfg(bootstrap)]
pub fn r#try(try_fn: fn(*mut u8), data: *mut u8, catch_fn: fn(*mut u8, *mut u8)) -> i32;

/// Emits a `!nontemporal` store according to LLVM (see their docs).
Expand Down
6 changes: 3 additions & 3 deletions library/panic_unwind/src/miri.rs
Original file line number Diff line number Diff line change
Expand Up @@ -8,14 +8,14 @@ type Payload = Box<Box<dyn Any + Send>>;

extern "Rust" {
/// Miri-provided extern function to begin unwinding.
fn miri_start_panic(payload: *mut u8) -> !;
fn miri_start_unwind(payload: *mut u8) -> !;
}

pub unsafe fn panic(payload: Box<dyn Any + Send>) -> u32 {
// The payload we pass to `miri_start_panic` will be exactly the argument we get
// The payload we pass to `miri_start_unwind` will be exactly the argument we get
// in `cleanup` below. So we just box it up once, to get something pointer-sized.
let payload_box: Payload = Box::new(payload);
miri_start_panic(Box::into_raw(payload_box) as *mut u8)
miri_start_unwind(Box::into_raw(payload_box) as *mut u8)
}

pub unsafe fn cleanup(payload_box: *mut u8) -> Box<dyn Any + Send> {
Expand Down
8 changes: 4 additions & 4 deletions library/std/src/panicking.rs
Original file line number Diff line number Diff line change
Expand Up @@ -508,12 +508,12 @@ pub unsafe fn r#try<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>>
// Access to the union's fields: this is `std` and we know that the `r#try`
// intrinsic fills in the `r` or `p` union field based on its return value.
//
// The call to `intrinsics::r#try` is made safe by:
// The call to `intrinsics::catch_unwind` is made safe by:
// - `do_call`, the first argument, can be called with the initial `data_ptr`.
// - `do_catch`, the second argument, can be called with the `data_ptr` as well.
// See their safety preconditions for more information
unsafe {
return if intrinsics::r#try(do_call::<F, R>, data_ptr, do_catch::<F, R>) == 0 {
return if intrinsics::catch_unwind(do_call::<F, R>, data_ptr, do_catch::<F, R>) == 0 {
Ok(ManuallyDrop::into_inner(data.r))
} else {
Err(ManuallyDrop::into_inner(data.p))
Expand All @@ -540,7 +540,7 @@ pub unsafe fn r#try<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>>
// Its must contains a valid `f` (type: F) value that can be use to fill
// `data.r`.
//
// This function cannot be marked as `unsafe` because `intrinsics::r#try`
// This function cannot be marked as `unsafe` because `intrinsics::catch_unwind`
// expects normal function pointers.
#[inline]
fn do_call<F: FnOnce() -> R, R>(data: *mut u8) {
Expand All @@ -562,7 +562,7 @@ pub unsafe fn r#try<R, F: FnOnce() -> R>(f: F) -> Result<R, Box<dyn Any + Send>>
// Since this uses `cleanup` it also hinges on a correct implementation of
// `__rustc_panic_cleanup`.
//
// This function cannot be marked as `unsafe` because `intrinsics::r#try`
// This function cannot be marked as `unsafe` because `intrinsics::catch_unwind`
// expects normal function pointers.
#[inline]
#[rustc_nounwind] // `intrinsic::r#try` requires catch fn to be nounwind
Expand Down
2 changes: 1 addition & 1 deletion src/tools/miri/src/concurrency/thread.rs
Original file line number Diff line number Diff line change
Expand Up @@ -143,7 +143,7 @@ pub struct Thread<'mir, 'tcx> {
join_status: ThreadJoinStatus,

/// Stack of active panic payloads for the current thread. Used for storing
/// the argument of the call to `miri_start_panic` (the panic payload) when unwinding.
/// the argument of the call to `miri_start_unwind` (the panic payload) when unwinding.
/// This is pointer-sized, and matches the `Payload` type in `src/libpanic_unwind/miri.rs`.
///
/// In real unwinding, the payload gets passed as an argument to the landing pad,
Expand Down
6 changes: 3 additions & 3 deletions src/tools/miri/src/shims/foreign_items.rs
Original file line number Diff line number Diff line change
Expand Up @@ -68,9 +68,9 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
let ret = match ret {
None =>
match link_name.as_str() {
"miri_start_panic" => {
// `check_shim` happens inside `handle_miri_start_panic`.
this.handle_miri_start_panic(abi, link_name, args, unwind)?;
"miri_start_unwind" => {
// `check_shim` happens inside `handle_miri_start_unwind`.
this.handle_miri_start_unwind(abi, link_name, args, unwind)?;
return Ok(None);
}
// This matches calls to the foreign item `panic_impl`.
Expand Down
2 changes: 1 addition & 1 deletion src/tools/miri/src/shims/intrinsics/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -54,7 +54,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {

// Some intrinsics are special and need the "ret".
match intrinsic_name {
"try" => return this.handle_try(args, dest, ret),
"catch_unwind" => return this.handle_catch_unwind(args, dest, ret),
_ => {}
}

Expand Down
16 changes: 8 additions & 8 deletions src/tools/miri/src/shims/panic.rs
Original file line number Diff line number Diff line change
Expand Up @@ -3,9 +3,9 @@
//! The core pieces of the runtime are:
//! - An implementation of `__rust_maybe_catch_panic` that pushes the invoked stack frame with
//! some extra metadata derived from the panic-catching arguments of `__rust_maybe_catch_panic`.
//! - A hack in `libpanic_unwind` that calls the `miri_start_panic` intrinsic instead of the
//! - A hack in `libpanic_unwind` that calls the `miri_start_unwind` intrinsic instead of the
//! target-native panic runtime. (This lives in the rustc repo.)
//! - An implementation of `miri_start_panic` that stores its argument (the panic payload), and then
//! - An implementation of `miri_start_unwind` that stores its argument (the panic payload), and then
//! immediately returns, but on the *unwind* edge (not the normal return edge), thus initiating unwinding.
//! - A hook executed each time a frame is popped, such that if the frame pushed by `__rust_maybe_catch_panic`
//! gets popped *during unwinding*, we take the panic payload and store it according to the extra
Expand Down Expand Up @@ -44,9 +44,9 @@ impl VisitProvenance for CatchUnwindData<'_> {

impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
/// Handles the special `miri_start_panic` intrinsic, which is called
/// Handles the special `miri_start_unwind` intrinsic, which is called
/// by libpanic_unwind to delegate the actual unwinding process to Miri.
fn handle_miri_start_panic(
fn handle_miri_start_unwind(
&mut self,
abi: Abi,
link_name: Symbol,
Expand All @@ -55,7 +55,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
) -> InterpResult<'tcx> {
let this = self.eval_context_mut();

trace!("miri_start_panic: {:?}", this.frame().instance);
trace!("miri_start_unwind: {:?}", this.frame().instance);

// Get the raw pointer stored in arg[0] (the panic payload).
let [payload] = this.check_shim(abi, Abi::Rust, link_name, args)?;
Expand All @@ -69,7 +69,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
}

/// Handles the `try` intrinsic, the underlying implementation of `std::panicking::try`.
fn handle_try(
fn handle_catch_unwind(
&mut self,
args: &[OpTy<'tcx, Provenance>],
dest: &PlaceTy<'tcx, Provenance>,
Expand All @@ -85,7 +85,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
// what that is), and returns 1.
// The `payload` is passed (by libstd) to `__rust_panic_cleanup`, which is then expected to
// return a `Box<dyn Any + Send + 'static>`.
// In Miri, `miri_start_panic` is passed exactly that type, so we make the `payload` simply
// In Miri, `miri_start_unwind` is passed exactly that type, so we make the `payload` simply
// a pointer to `Box<dyn Any + Send + 'static>`.

// Get all the arguments.
Expand Down Expand Up @@ -141,7 +141,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
// We set the return value of `try` to 1, since there was a panic.
this.write_scalar(Scalar::from_i32(1), &catch_unwind.dest)?;

// The Thread's `panic_payload` holds what was passed to `miri_start_panic`.
// The Thread's `panic_payload` holds what was passed to `miri_start_unwind`.
// This is exactly the second argument we need to pass to `catch_fn`.
let payload = this.active_thread_mut().panic_payloads.pop().unwrap();

Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@ fn main() {
unsafe {
// Make sure we check the ABI when Miri itself invokes a function
// as part of a shim implementation.
std::intrinsics::r#try(
std::intrinsics::catch_unwind(
//~^ ERROR: calling a function with ABI C using caller ABI Rust
std::mem::transmute::<extern "C" fn(*mut u8), _>(try_fn),
std::ptr::null_mut(),
Expand Down
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
error: Undefined Behavior: calling a function with ABI C using caller ABI Rust
--> $DIR/check_callback_abi.rs:LL:CC
|
LL | / std::intrinsics::r#try(
LL | / std::intrinsics::catch_unwind(
LL | |
LL | | std::mem::transmute::<extern "C" fn(*mut u8), _>(try_fn),
LL | | std::ptr::null_mut(),
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -3,10 +3,10 @@
#![feature(c_unwind)]

extern "C" {
fn miri_start_panic(payload: *mut u8) -> !;
fn miri_start_unwind(payload: *mut u8) -> !;
}

fn main() {
unsafe { miri_start_panic(&mut 0) }
unsafe { miri_start_unwind(&mut 0) }
//~^ ERROR: unwinding past a stack frame that does not allow unwinding
}
Original file line number Diff line number Diff line change
@@ -1,15 +1,15 @@
WARNING: the flag `-Zmiri-disable-abi-check` is deprecated and planned to be removed.
If you have a use-case for it, please file an issue.
error: Undefined Behavior: unwinding past a stack frame that does not allow unwinding
--> $DIR/bad_miri_start_panic.rs:LL:CC
--> $DIR/bad_miri_start_unwind.rs:LL:CC
|
LL | unsafe { miri_start_panic(&mut 0) }
| ^^^^^^^^^^^^^^^^^^^^^^^^ unwinding past a stack frame that does not allow unwinding
LL | unsafe { miri_start_unwind(&mut 0) }
| ^^^^^^^^^^^^^^^^^^^^^^^^^ unwinding past a stack frame that does not allow unwinding
|
= help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
= help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
= note: BACKTRACE:
= note: inside `main` at $DIR/bad_miri_start_panic.rs:LL:CC
= note: inside `main` at $DIR/bad_miri_start_unwind.rs:LL:CC

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

Expand Down
4 changes: 2 additions & 2 deletions src/tools/miri/tests/fail/panic/unwind_panic_abort.rs
Original file line number Diff line number Diff line change
Expand Up @@ -3,11 +3,11 @@
//! Unwinding despite `-C panic=abort` is an error.

extern "Rust" {
fn miri_start_panic(payload: *mut u8) -> !;
fn miri_start_unwind(payload: *mut u8) -> !;
}

fn main() {
unsafe {
miri_start_panic(&mut 0); //~ ERROR: unwinding past a stack frame that does not allow unwinding
miri_start_unwind(&mut 0); //~ ERROR: unwinding past a stack frame that does not allow unwinding
}
}
4 changes: 2 additions & 2 deletions src/tools/miri/tests/fail/panic/unwind_panic_abort.stderr
Original file line number Diff line number Diff line change
@@ -1,8 +1,8 @@
error: Undefined Behavior: unwinding past a stack frame that does not allow unwinding
--> $DIR/unwind_panic_abort.rs:LL:CC
|
LL | miri_start_panic(&mut 0);
| ^^^^^^^^^^^^^^^^^^^^^^^^ unwinding past a stack frame that does not allow unwinding
LL | miri_start_unwind(&mut 0);
| ^^^^^^^^^^^^^^^^^^^^^^^^^ unwinding past a stack frame that does not allow unwinding
|
= help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
= help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -15,7 +15,7 @@ fn main() {
unsafe {
let _ = malloc(0);
std::mem::transmute::<fn(), extern "C" fn()>(foo)();
std::intrinsics::r#try(
std::intrinsics::catch_unwind(
std::mem::transmute::<extern "C" fn(*mut u8), _>(try_fn),
std::ptr::null_mut(),
|_, _| unreachable!(),
Expand Down
2 changes: 1 addition & 1 deletion src/tools/miri/tests/utils/miri_extern.rs
Original file line number Diff line number Diff line change
Expand Up @@ -56,7 +56,7 @@ extern "Rust" {
///
/// This is internal and unstable and should not be used; we give it here
/// just to be complete.
pub fn miri_start_panic(payload: *mut u8) -> !;
pub fn miri_start_unwind(payload: *mut u8) -> !;

/// Miri-provided extern function to get the internal unique identifier for the allocation that a pointer
/// points to. If this pointer is invalid (not pointing to an allocation), interpretation will abort.
Expand Down
2 changes: 1 addition & 1 deletion tests/assembly/wasm_exceptions.rs
Original file line number Diff line number Diff line change
Expand Up @@ -41,7 +41,7 @@ pub fn test_cleanup() {
#[no_mangle]
pub fn test_rtry() {
unsafe {
core::intrinsics::r#try(|_| {
core::intrinsics::catch_unwind(|_| {
may_panic();
}, core::ptr::null_mut(), |data, exception| {
log_number(data as usize);
Expand Down
2 changes: 1 addition & 1 deletion tests/codegen/wasm_exceptions.rs
Original file line number Diff line number Diff line change
Expand Up @@ -35,7 +35,7 @@ pub fn test_cleanup() {
#[no_mangle]
pub fn test_rtry() {
unsafe {
core::intrinsics::r#try(|_| {
core::intrinsics::catch_unwind(|_| {
may_panic();
}, core::ptr::null_mut(), |data, exception| {
log_number(data as usize);
Expand Down
2 changes: 1 addition & 1 deletion tests/run-make/wasm-exceptions-nostd/src/lib.rs
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,7 @@ pub extern "C" fn start() -> usize {
let data = 0x1234usize as *mut u8; // Something to recognize

unsafe {
core::intrinsics::r#try(|data: *mut u8| {
core::intrinsics::catch_unwind(|data: *mut u8| {
let _log_on_drop = LogOnDrop;

logging::log_str(&alloc::format!("`r#try` called with ptr {:?}", data));
Expand Down
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