Rollup of 10 pull requests

Cargo.lock

@@ -5460,9 +5460,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-tree"
-version = "0.1.8"
+version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a60657cfbf397c603257a8230b3f427e6a2a4e5911a59331b9bb4dffff5b608"
+checksum = "1712b40907f8d9bc2bc66763ab61dec914b7123d7149e59feb0d4e2a95fc4967"
 dependencies = [
  "ansi_term 0.12.1",
  "atty",

README.md

@@ -31,7 +31,7 @@ by running `./x.py --help` or reading the [rustc dev guide][rustcguidebuild].
    * `g++` 5.1 or later or `clang++` 3.5 or later
    * `python` 3 or 2.7
    * GNU `make` 3.81 or later
-   * `cmake` 3.4.3 or later
+   * `cmake` 3.13.4 or later
    * `ninja`
    * `curl`
    * `git`

compiler/rustc_codegen_cranelift/src/base.rs

@@ -832,6 +832,27 @@ fn codegen_stmt<'tcx>(
             }
         }
         StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"),
+        StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
+          src,
+          dst,
+          count,
+        }) => {
+            let dst = codegen_operand(fx, dst);
+            let pointee = dst
+              .layout()
+              .pointee_info_at(fx, rustc_target::abi::Size::ZERO)
+              .expect("Expected pointer");
+            let dst = dst.load_scalar(fx);
+            let src = codegen_operand(fx, src).load_scalar(fx);
+            let count = codegen_operand(fx, count).load_scalar(fx);
+            let elem_size: u64 = pointee.size.bytes();
+            let bytes = if elem_size != 1 {
+               fx.bcx.ins().imul_imm(count, elem_size as i64)
+            } else {
+               count
+            };
+            fx.bcx.call_memcpy(fx.cx.module.target_config(), dst, src, bytes);
+        }
     }
 }
 

compiler/rustc_codegen_ssa/src/lib.rs

@@ -9,6 +9,7 @@
 #![feature(or_patterns)]
 #![feature(associated_type_bounds)]
 #![recursion_limit = "256"]
+#![feature(box_syntax)]
 
 //! This crate contains codegen code that is used by all codegen backends (LLVM and others).
 //! The backend-agnostic functions of this crate use functions defined in various traits that

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -641,67 +641,73 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             return;
         }
 
-        if intrinsic.is_some() && intrinsic != Some(sym::drop_in_place) {
-            let intrinsic = intrinsic.unwrap();
-            let dest = match ret_dest {
-                _ if fn_abi.ret.is_indirect() => llargs[0],
-                ReturnDest::Nothing => {
-                    bx.const_undef(bx.type_ptr_to(bx.arg_memory_ty(&fn_abi.ret)))
-                }
-                ReturnDest::IndirectOperand(dst, _) | ReturnDest::Store(dst) => dst.llval,
-                ReturnDest::DirectOperand(_) => {
-                    bug!("Cannot use direct operand with an intrinsic call")
-                }
-            };
+        match intrinsic {
+            None | Some(sym::drop_in_place) => {}
+            Some(sym::copy_nonoverlapping) => unreachable!(),
+            Some(intrinsic) => {
+                let dest = match ret_dest {
+                    _ if fn_abi.ret.is_indirect() => llargs[0],
+                    ReturnDest::Nothing => {
+                        bx.const_undef(bx.type_ptr_to(bx.arg_memory_ty(&fn_abi.ret)))
+                    }
+                    ReturnDest::IndirectOperand(dst, _) | ReturnDest::Store(dst) => dst.llval,
+                    ReturnDest::DirectOperand(_) => {
+                        bug!("Cannot use direct operand with an intrinsic call")
+                    }
+                };
 
-            let args: Vec<_> = args
-                .iter()
-                .enumerate()
-                .map(|(i, arg)| {
-                    // The indices passed to simd_shuffle* in the
-                    // third argument must be constant. This is
-                    // checked by const-qualification, which also
-                    // promotes any complex rvalues to constants.
-                    if i == 2 && intrinsic.as_str().starts_with("simd_shuffle") {
-                        if let mir::Operand::Constant(constant) = arg {
-                            let c = self.eval_mir_constant(constant);
-                            let (llval, ty) = self.simd_shuffle_indices(
-                                &bx,
-                                constant.span,
-                                constant.literal.ty,
-                                c,
-                            );
-                            return OperandRef { val: Immediate(llval), layout: bx.layout_of(ty) };
-                        } else {
-                            span_bug!(span, "shuffle indices must be constant");
+                let args: Vec<_> = args
+                    .iter()
+                    .enumerate()
+                    .map(|(i, arg)| {
+                        // The indices passed to simd_shuffle* in the
+                        // third argument must be constant. This is
+                        // checked by const-qualification, which also
+                        // promotes any complex rvalues to constants.
+                        if i == 2 && intrinsic.as_str().starts_with("simd_shuffle") {
+                            if let mir::Operand::Constant(constant) = arg {
+                                let c = self.eval_mir_constant(constant);
+                                let (llval, ty) = self.simd_shuffle_indices(
+                                    &bx,
+                                    constant.span,
+                                    constant.literal.ty,
+                                    c,
+                                );
+                                return OperandRef {
+                                    val: Immediate(llval),
+                                    layout: bx.layout_of(ty),
+                                };
+                            } else {
+                                span_bug!(span, "shuffle indices must be constant");
+                            }
                         }
-                    }
 
-                    self.codegen_operand(&mut bx, arg)
-                })
-                .collect();
+                        self.codegen_operand(&mut bx, arg)
+                    })
+                    .collect();
+
+                Self::codegen_intrinsic_call(
+                    &mut bx,
+                    *instance.as_ref().unwrap(),
+                    &fn_abi,
+                    &args,
+                    dest,
+                    span,
+                );
 
-            Self::codegen_intrinsic_call(
-                &mut bx,
-                *instance.as_ref().unwrap(),
-                &fn_abi,
-                &args,
-                dest,
-                span,
-            );
+                if let ReturnDest::IndirectOperand(dst, _) = ret_dest {
+                    self.store_return(&mut bx, ret_dest, &fn_abi.ret, dst.llval);
+                }
 
-            if let ReturnDest::IndirectOperand(dst, _) = ret_dest {
-                self.store_return(&mut bx, ret_dest, &fn_abi.ret, dst.llval);
-            }
+                if let Some((_, target)) = *destination {
+                    helper.maybe_sideeffect(self.mir, &mut bx, &[target]);
+                    helper.funclet_br(self, &mut bx, target);
+                } else {
+                    bx.unreachable();
+                }
 
-            if let Some((_, target)) = *destination {
-                helper.maybe_sideeffect(self.mir, &mut bx, &[target]);
-                helper.funclet_br(self, &mut bx, target);
-            } else {
-                bx.unreachable();
+                return;
             }
-
-            return;
         }
 
         // Split the rust-call tupled arguments off.

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -125,19 +125,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 let offset = args[1].immediate();
                 bx.gep(ptr, &[offset])
             }
-
-            sym::copy_nonoverlapping => {
-                copy_intrinsic(
-                    bx,
-                    false,
-                    false,
-                    substs.type_at(0),
-                    args[1].immediate(),
-                    args[0].immediate(),
-                    args[2].immediate(),
-                );
-                return;
-            }
             sym::copy => {
                 copy_intrinsic(
                     bx,

compiler/rustc_codegen_ssa/src/mir/statement.rs

@@ -115,6 +115,26 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 self.codegen_coverage(&mut bx, coverage.clone());
                 bx
             }
+            mir::StatementKind::CopyNonOverlapping(box mir::CopyNonOverlapping {
+                ref src,
+                ref dst,
+                ref count,
+            }) => {
+                let dst_val = self.codegen_operand(&mut bx, dst);
+                let src_val = self.codegen_operand(&mut bx, src);
+                let count = self.codegen_operand(&mut bx, count).immediate();
+                let pointee_layout = dst_val
+                    .layout
+                    .pointee_info_at(&mut bx, rustc_target::abi::Size::ZERO)
+                    .expect("Expected pointer");
+                let bytes = bx.mul(count, bx.const_usize(pointee_layout.size.bytes()));
+
+                let align = pointee_layout.align;
+                let dst = dst_val.immediate();
+                let src = src_val.immediate();
+                bx.memcpy(dst, align, src, align, bytes, crate::MemFlags::empty());
+                bx
+            }
             mir::StatementKind::FakeRead(..)
             | mir::StatementKind::Retag { .. }
             | mir::StatementKind::AscribeUserType(..)

compiler/rustc_driver/Cargo.toml

@@ -12,7 +12,7 @@ libc = "0.2"
 atty = "0.2"
 tracing = { version = "0.1.25" }
 tracing-subscriber = { version = "0.2.16", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
-tracing-tree = "0.1.8"
+tracing-tree = "0.1.9"
 rustc_middle = { path = "../rustc_middle" }
 rustc_ast_pretty = { path = "../rustc_ast_pretty" }
 rustc_target = { path = "../rustc_target" }

compiler/rustc_feature/src/accepted.rs

@@ -275,6 +275,8 @@ declare_features! (
     (accepted, move_ref_pattern, "1.49.0", Some(68354), None),
     /// The smallest useful subset of `const_generics`.
     (accepted, min_const_generics, "1.51.0", Some(74878), None),
+    /// The `unsafe_op_in_unsafe_fn` lint (allowed by default): no longer treat an unsafe function as an unsafe block.
+    (accepted, unsafe_block_in_unsafe_fn, "1.51.0", Some(71668), None),
 
     // -------------------------------------------------------------------------
     // feature-group-end: accepted features

compiler/rustc_feature/src/active.rs

@@ -557,9 +557,6 @@ declare_features! (
     /// Allows the use of `#[ffi_const]` on foreign functions.
     (active, ffi_const, "1.45.0", Some(58328), None),
 
-    /// No longer treat an unsafe function as an unsafe block.
-    (active, unsafe_block_in_unsafe_fn, "1.45.0", Some(71668), None),
-
     /// Allows `extern "avr-interrupt" fn()` and `extern "avr-non-blocking-interrupt" fn()`.
     (active, abi_avr_interrupt, "1.45.0", Some(69664), None),
 

compiler/rustc_lint_defs/src/builtin.rs

@@ -8,7 +8,6 @@
 
 use crate::{declare_lint, declare_lint_pass};
 use rustc_span::edition::Edition;
-use rustc_span::symbol::sym;
 
 declare_lint! {
     /// The `forbidden_lint_groups` lint detects violations of
@@ -2489,16 +2488,11 @@ declare_lint! {
 
 declare_lint! {
     /// The `unsafe_op_in_unsafe_fn` lint detects unsafe operations in unsafe
-    /// functions without an explicit unsafe block. This lint only works on
-    /// the [**nightly channel**] with the
-    /// `#![feature(unsafe_block_in_unsafe_fn)]` feature.
-    ///
-    /// [**nightly channel**]: https://doc.rust-lang.org/book/appendix-07-nightly-rust.html
+    /// functions without an explicit unsafe block.
     ///
     /// ### Example
     ///
     /// ```rust,compile_fail
-    /// #![feature(unsafe_block_in_unsafe_fn)]
     /// #![deny(unsafe_op_in_unsafe_fn)]
     ///
     /// unsafe fn foo() {}
@@ -2536,7 +2530,6 @@ declare_lint! {
     pub UNSAFE_OP_IN_UNSAFE_FN,
     Allow,
     "unsafe operations in unsafe functions without an explicit unsafe block are deprecated",
-    @feature_gate = sym::unsafe_block_in_unsafe_fn;
 }
 
 declare_lint! {

compiler/rustc_middle/src/mir/mod.rs

@@ -1541,6 +1541,11 @@ pub enum StatementKind<'tcx> {
     /// counter varible at runtime, each time the code region is executed.
     Coverage(Box<Coverage>),
 
+    /// Denotes a call to the intrinsic function copy_overlapping, where `src_dst` denotes the
+    /// memory being read from and written to(one field to save memory), and size
+    /// indicates how many bytes are being copied over.
+    CopyNonOverlapping(Box<CopyNonOverlapping<'tcx>>),
+
     /// No-op. Useful for deleting instructions without affecting statement indices.
     Nop,
 }
@@ -1659,6 +1664,13 @@ impl Debug for Statement<'_> {
                     write!(fmt, "Coverage::{:?}", coverage.kind)
                 }
             }
+            CopyNonOverlapping(box crate::mir::CopyNonOverlapping {
+                ref src,
+                ref dst,
+                ref count,
+            }) => {
+                write!(fmt, "copy_nonoverlapping(src={:?}, dst={:?}, count={:?})", src, dst, count)
+            }
             Nop => write!(fmt, "nop"),
         }
     }
@@ -1670,6 +1682,14 @@ pub struct Coverage {
     pub code_region: Option<CodeRegion>,
 }
 
+#[derive(Clone, Debug, PartialEq, TyEncodable, TyDecodable, Hash, HashStable, TypeFoldable)]
+pub struct CopyNonOverlapping<'tcx> {
+    pub src: Operand<'tcx>,
+    pub dst: Operand<'tcx>,
+    /// Number of elements to copy from src to dest, not bytes.
+    pub count: Operand<'tcx>,
+}
+
 ///////////////////////////////////////////////////////////////////////////
 // Places
 

compiler/rustc_middle/src/mir/query.rs

@@ -28,11 +28,9 @@ pub enum UnsafetyViolationKind {
     BorrowPacked,
     /// Unsafe operation in an `unsafe fn` but outside an `unsafe` block.
     /// Has to be handled as a lint for backwards compatibility.
-    /// Should stay gated under `#![feature(unsafe_block_in_unsafe_fn)]`.
     UnsafeFn,
     /// Borrow of packed field in an `unsafe fn` but outside an `unsafe` block.
     /// Has to be handled as a lint for backwards compatibility.
-    /// Should stay gated under `#![feature(unsafe_block_in_unsafe_fn)]`.
     UnsafeFnBorrowPacked,
 }
 

compiler/rustc_middle/src/mir/visit.rs

@@ -436,6 +436,15 @@ macro_rules! make_mir_visitor {
                             location
                         )
                     }
+                    StatementKind::CopyNonOverlapping(box crate::mir::CopyNonOverlapping{
+                      ref $($mutability)? src,
+                      ref $($mutability)? dst,
+                      ref $($mutability)? count,
+                    }) => {
+                      self.visit_operand(src, location);
+                      self.visit_operand(dst, location);
+                      self.visit_operand(count, location)
+                    }
                     StatementKind::Nop => {}
                 }
             }

compiler/rustc_mir/src/borrow_check/invalidation.rs

@@ -92,6 +92,15 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
                     self.consume_operand(location, input);
                 }
             }
+            StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
+                ref src,
+                ref dst,
+                ref count,
+            }) => {
+                self.consume_operand(location, src);
+                self.consume_operand(location, dst);
+                self.consume_operand(location, count);
+            }
             StatementKind::Nop
             | StatementKind::Coverage(..)
             | StatementKind::AscribeUserType(..)

compiler/rustc_mir/src/borrow_check/mod.rs

@@ -626,6 +626,15 @@ impl<'cx, 'tcx> dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtxt<'cx, 'tc
                     self.consume_operand(location, (input, span), flow_state);
                 }
             }
+
+            StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping {
+                ..
+            }) => {
+                span_bug!(
+                    span,
+                    "Unexpected CopyNonOverlapping, should only appear after lower_intrinsics",
+                )
+            }
             StatementKind::Nop
             | StatementKind::Coverage(..)
             | StatementKind::AscribeUserType(..)