diff options
| -rw-r--r-- | compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs | 13 | ||||
| -rw-r--r-- | compiler/rustc_codegen_gcc/src/intrinsic/mod.rs | 14 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/context.rs | 3 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/intrinsic.rs | 9 | ||||
| -rw-r--r-- | compiler/rustc_const_eval/src/interpret/intrinsics.rs | 22 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/check/intrinsic.rs | 4 | ||||
| -rw-r--r-- | compiler/rustc_span/src/symbol.rs | 1 | ||||
| -rw-r--r-- | library/core/src/intrinsics.rs | 34 | ||||
| -rw-r--r-- | library/core/src/slice/cmp.rs | 21 | ||||
| -rw-r--r-- | src/tools/miri/tests/fail/uninit_buffer.stderr | 4 | ||||
| -rw-r--r-- | src/tools/miri/tests/fail/uninit_buffer_with_provenance.stderr | 4 | ||||
| -rw-r--r-- | tests/codegen/intrinsics/compare_bytes.rs | 34 | ||||
| -rw-r--r-- | tests/ui/consts/const-compare-bytes-ub.rs | 41 | ||||
| -rw-r--r-- | tests/ui/consts/const-compare-bytes-ub.stderr | 54 | ||||
| -rw-r--r-- | tests/ui/consts/const-compare-bytes.rs | 27 | ||||
| -rw-r--r-- | tests/ui/proc-macro/meta-macro-hygiene.stdout | 2 | ||||
| -rw-r--r-- | tests/ui/proc-macro/nonterminal-token-hygiene.stdout | 2 |
17 files changed, 267 insertions, 22 deletions
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs index e3006b253b7..dcb080b9ec1 100644 --- a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs +++ b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs @@ -1155,6 +1155,19 @@ fn codegen_regular_intrinsic_call<'tcx>( ret.write_cvalue(fx, CValue::by_val(is_eq_value, ret.layout())); } + sym::compare_bytes => { + intrinsic_args!(fx, args => (lhs_ptr, rhs_ptr, bytes_val); intrinsic); + let lhs_ptr = lhs_ptr.load_scalar(fx); + let rhs_ptr = rhs_ptr.load_scalar(fx); + let bytes_val = bytes_val.load_scalar(fx); + + let params = vec![AbiParam::new(fx.pointer_type); 3]; + let returns = vec![AbiParam::new(types::I32)]; + let args = &[lhs_ptr, rhs_ptr, bytes_val]; + let cmp = fx.lib_call("memcmp", params, returns, args)[0]; + ret.write_cvalue(fx, CValue::by_val(cmp, ret.layout())); + } + sym::const_allocate => { intrinsic_args!(fx, args => (_size, _align); intrinsic); diff --git a/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs b/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs index 68edde13829..eca2abf2775 100644 --- a/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs +++ b/compiler/rustc_codegen_gcc/src/intrinsic/mod.rs @@ -302,6 +302,20 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> { } } + sym::compare_bytes => { + let a = args[0].immediate(); + let b = args[1].immediate(); + let n = args[2].immediate(); + + let void_ptr_type = self.context.new_type::<*const ()>(); + let a_ptr = self.bitcast(a, void_ptr_type); + let b_ptr = self.bitcast(b, void_ptr_type); + + let builtin = self.context.get_builtin_function("memcmp"); + let cmp = self.context.new_call(None, builtin, &[a_ptr, b_ptr, n]); + self.sext(cmp, self.type_ix(32)) + } + sym::black_box => { args[0].val.store(self, result); diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs index 3577fb2d951..2d23be6cd52 100644 --- a/compiler/rustc_codegen_llvm/src/context.rs +++ b/compiler/rustc_codegen_llvm/src/context.rs @@ -891,7 +891,8 @@ impl<'ll> CodegenCx<'ll, '_> { ifn!("llvm.prefetch", fn(ptr, t_i32, t_i32, t_i32) -> void); // This isn't an "LLVM intrinsic", but LLVM's optimization passes - // recognize it like one and we assume it exists in `core::slice::cmp` + // recognize it like one (including turning it into `bcmp` sometimes) + // and we use it to implement intrinsics like `raw_eq` and `compare_bytes` match self.sess().target.arch.as_ref() { "avr" | "msp430" => ifn!("memcmp", fn(ptr, ptr, t_isize) -> t_i16), _ => ifn!("memcmp", fn(ptr, ptr, t_isize) -> t_i32), diff --git a/compiler/rustc_codegen_llvm/src/intrinsic.rs b/compiler/rustc_codegen_llvm/src/intrinsic.rs index 6f1e4c5178a..4e86094ce3b 100644 --- a/compiler/rustc_codegen_llvm/src/intrinsic.rs +++ b/compiler/rustc_codegen_llvm/src/intrinsic.rs @@ -329,6 +329,15 @@ impl<'ll, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'_, 'll, 'tcx> { } } + sym::compare_bytes => { + let cmp = self.call_intrinsic( + "memcmp", + &[args[0].immediate(), args[1].immediate(), args[2].immediate()], + ); + // Some targets have `memcmp` returning `i16`, but the intrinsic is always `i32`. + self.sext(cmp, self.type_ix(32)) + } + sym::black_box => { args[0].val.store(self, result); let result_val_span = [result.llval]; diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs index 123eb3125f0..f22cd919c36 100644 --- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs +++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs @@ -261,6 +261,10 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { sym::write_bytes => { self.write_bytes_intrinsic(&args[0], &args[1], &args[2])?; } + sym::compare_bytes => { + let result = self.compare_bytes_intrinsic(&args[0], &args[1], &args[2])?; + self.write_scalar(result, dest)?; + } sym::arith_offset => { let ptr = self.read_pointer(&args[0])?; let offset_count = self.read_target_isize(&args[1])?; @@ -643,6 +647,24 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { self.write_bytes_ptr(dst, bytes) } + pub(crate) fn compare_bytes_intrinsic( + &mut self, + left: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>, + right: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>, + byte_count: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>, + ) -> InterpResult<'tcx, Scalar<M::Provenance>> { + let left = self.read_pointer(left)?; + let right = self.read_pointer(right)?; + let n = Size::from_bytes(self.read_target_usize(byte_count)?); + + let left_bytes = self.read_bytes_ptr_strip_provenance(left, n)?; + let right_bytes = self.read_bytes_ptr_strip_provenance(right, n)?; + + // `Ordering`'s discriminants are -1/0/+1, so casting does the right thing. + let result = Ord::cmp(left_bytes, right_bytes) as i32; + Ok(Scalar::from_i32(result)) + } + pub(crate) fn raw_eq_intrinsic( &mut self, lhs: &OpTy<'tcx, <M as Machine<'mir, 'tcx>>::Provenance>, diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs index 970efaf312c..f89e2e5c25b 100644 --- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs +++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs @@ -273,6 +273,10 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) { ], Ty::new_unit(tcx), ), + sym::compare_bytes => { + let byte_ptr = Ty::new_imm_ptr(tcx, tcx.types.u8); + (0, vec![byte_ptr, byte_ptr, tcx.types.usize], tcx.types.i32) + } sym::write_bytes | sym::volatile_set_memory => ( 1, vec![ diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 44820ae6f72..9ea9efb047c 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -498,6 +498,7 @@ symbols! { cold, collapse_debuginfo, column, + compare_bytes, compare_exchange, compare_exchange_weak, compile_error, diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs index d042aaf3084..9ef2c7cde02 100644 --- a/library/core/src/intrinsics.rs +++ b/library/core/src/intrinsics.rs @@ -2385,6 +2385,25 @@ extern "rust-intrinsic" { #[rustc_nounwind] pub fn raw_eq<T>(a: &T, b: &T) -> bool; + /// Lexicographically compare `[left, left + bytes)` and `[right, right + bytes)` + /// as unsigned bytes, returning negative if `left` is less, zero if all the + /// bytes match, or positive if `right` is greater. + /// + /// This underlies things like `<[u8]>::cmp`, and will usually lower to `memcmp`. + /// + /// # Safety + /// + /// `left` and `right` must each be [valid] for reads of `bytes` bytes. + /// + /// Note that this applies to the whole range, not just until the first byte + /// that differs. That allows optimizations that can read in large chunks. + /// + /// [valid]: crate::ptr#safety + #[cfg(not(bootstrap))] + #[rustc_const_unstable(feature = "const_intrinsic_compare_bytes", issue = "none")] + #[rustc_nounwind] + pub fn compare_bytes(left: *const u8, right: *const u8, bytes: usize) -> i32; + /// See documentation of [`std::hint::black_box`] for details. /// /// [`std::hint::black_box`]: crate::hint::black_box @@ -2825,3 +2844,18 @@ pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) { write_bytes(dst, val, count) } } + +/// Backfill for bootstrap +#[cfg(bootstrap)] +pub unsafe fn compare_bytes(left: *const u8, right: *const u8, bytes: usize) -> i32 { + extern "C" { + fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> crate::ffi::c_int; + } + + if bytes != 0 { + // SAFETY: Since bytes is non-zero, the caller has met `memcmp`'s requirements. + unsafe { memcmp(left, right, bytes).into() } + } else { + 0 + } +} diff --git a/library/core/src/slice/cmp.rs b/library/core/src/slice/cmp.rs index 7601dd3c756..075347b80d0 100644 --- a/library/core/src/slice/cmp.rs +++ b/library/core/src/slice/cmp.rs @@ -1,22 +1,12 @@ //! Comparison traits for `[T]`. use crate::cmp::{self, BytewiseEq, Ordering}; -use crate::ffi; +use crate::intrinsics::compare_bytes; use crate::mem; use super::from_raw_parts; use super::memchr; -extern "C" { - /// Calls implementation provided memcmp. - /// - /// Interprets the data as u8. - /// - /// Returns 0 for equal, < 0 for less than and > 0 for greater - /// than. - fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> ffi::c_int; -} - #[stable(feature = "rust1", since = "1.0.0")] impl<A, B> PartialEq<[B]> for [A] where @@ -74,7 +64,8 @@ where } } -// Use memcmp for bytewise equality when the types allow +// When each element can be compared byte-wise, we can compare all the bytes +// from the whole size in one call to the intrinsics. impl<A, B> SlicePartialEq<B> for [A] where A: BytewiseEq<B>, @@ -88,7 +79,7 @@ where // The two slices have been checked to have the same size above. unsafe { let size = mem::size_of_val(self); - memcmp(self.as_ptr() as *const u8, other.as_ptr() as *const u8, size) == 0 + compare_bytes(self.as_ptr() as *const u8, other.as_ptr() as *const u8, size) == 0 } } } @@ -183,7 +174,7 @@ impl<A: Ord> SliceOrd for A { } } -// memcmp compares a sequence of unsigned bytes lexicographically. +// `compare_bytes` compares a sequence of unsigned bytes lexicographically. // this matches the order we want for [u8], but no others (not even [i8]). impl SliceOrd for u8 { #[inline] @@ -195,7 +186,7 @@ impl SliceOrd for u8 { // SAFETY: `left` and `right` are references and are thus guaranteed to be valid. // We use the minimum of both lengths which guarantees that both regions are // valid for reads in that interval. - let mut order = unsafe { memcmp(left.as_ptr(), right.as_ptr(), len) as isize }; + let mut order = unsafe { compare_bytes(left.as_ptr(), right.as_ptr(), len) as isize }; if order == 0 { order = diff; } diff --git a/src/tools/miri/tests/fail/uninit_buffer.stderr b/src/tools/miri/tests/fail/uninit_buffer.stderr index 8da532cfff0..90210bf7f11 100644 --- a/src/tools/miri/tests/fail/uninit_buffer.stderr +++ b/src/tools/miri/tests/fail/uninit_buffer.stderr @@ -1,8 +1,8 @@ error: Undefined Behavior: reading memory at ALLOC[0x0..0x10], but memory is uninitialized at [0x4..0x10], and this operation requires initialized memory --> RUSTLIB/core/src/slice/cmp.rs:LL:CC | -LL | let mut order = unsafe { memcmp(left.as_ptr(), right.as_ptr(), len) as isize }; - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x10], but memory is uninitialized at [0x4..0x10], and this operation requires initialized memory +LL | let mut order = unsafe { compare_bytes(left.as_ptr(), right.as_ptr(), len) as isize }; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x10], but memory is uninitialized at [0x4..0x10], and this operation requires initialized memory | = 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 diff --git a/src/tools/miri/tests/fail/uninit_buffer_with_provenance.stderr b/src/tools/miri/tests/fail/uninit_buffer_with_provenance.stderr index 210fc8e109a..701ec601369 100644 --- a/src/tools/miri/tests/fail/uninit_buffer_with_provenance.stderr +++ b/src/tools/miri/tests/fail/uninit_buffer_with_provenance.stderr @@ -1,8 +1,8 @@ error: Undefined Behavior: reading memory at ALLOC[0x0..0x8], but memory is uninitialized at [0x4..0x8], and this operation requires initialized memory --> RUSTLIB/core/src/slice/cmp.rs:LL:CC | -LL | let mut order = unsafe { memcmp(left.as_ptr(), right.as_ptr(), len) as isize }; - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x8], but memory is uninitialized at [0x4..0x8], and this operation requires initialized memory +LL | let mut order = unsafe { compare_bytes(left.as_ptr(), right.as_ptr(), len) as isize }; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x8], but memory is uninitialized at [0x4..0x8], and this operation requires initialized memory | = 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 diff --git a/tests/codegen/intrinsics/compare_bytes.rs b/tests/codegen/intrinsics/compare_bytes.rs new file mode 100644 index 00000000000..e69224d818c --- /dev/null +++ b/tests/codegen/intrinsics/compare_bytes.rs @@ -0,0 +1,34 @@ +// revisions: INT32 INT16 +// compile-flags: -O +// [INT32] ignore-16bit +// [INT16] only-16bit + +#![crate_type = "lib"] +#![feature(core_intrinsics)] + +use std::intrinsics::compare_bytes; + +#[no_mangle] +// CHECK-LABEL: @bytes_cmp( +pub unsafe fn bytes_cmp(a: *const u8, b: *const u8, n: usize) -> i32 { + // INT32: %[[TEMP:.+]] = tail call i32 @memcmp(ptr %a, ptr %b, {{i32|i64}} %n) + // INT32-NOT: sext + // INT32: ret i32 %[[TEMP]] + + // INT16: %[[TEMP1:.+]] = tail call i16 @memcmp(ptr %a, ptr %b, i16 %n) + // INT16: %[[TEMP2:.+]] = sext i16 %[[TEMP1]] to i32 + // INT16: ret i32 %[[TEMP2]] + compare_bytes(a, b, n) +} + +// Ensure that, even though there's an `sext` emitted by the intrinsic, +// that doesn't end up pessiming checks against zero. +#[no_mangle] +// CHECK-LABEL: @bytes_eq( +pub unsafe fn bytes_eq(a: *const u8, b: *const u8, n: usize) -> bool { + // CHECK: call {{.+}} @{{bcmp|memcmp}}(ptr %a, ptr %b, {{i16|i32|i64}} %n) + // CHECK-NOT: sext + // INT32: icmp eq i32 + // INT16: icmp eq i16 + compare_bytes(a, b, n) == 0_i32 +} diff --git a/tests/ui/consts/const-compare-bytes-ub.rs b/tests/ui/consts/const-compare-bytes-ub.rs new file mode 100644 index 00000000000..2b4062fd22b --- /dev/null +++ b/tests/ui/consts/const-compare-bytes-ub.rs @@ -0,0 +1,41 @@ +// check-fail + +#![feature(core_intrinsics)] +#![feature(const_intrinsic_compare_bytes)] +use std::intrinsics::compare_bytes; +use std::mem::MaybeUninit; + +fn main() { + const LHS_NULL: i32 = unsafe { + compare_bytes(0 as *const u8, 2 as *const u8, 0) + //~^ ERROR evaluation of constant value failed + }; + const RHS_NULL: i32 = unsafe { + compare_bytes(1 as *const u8, 0 as *const u8, 0) + //~^ ERROR evaluation of constant value failed + }; + const DANGLING_PTR_NON_ZERO_LENGTH: i32 = unsafe { + compare_bytes(1 as *const u8, 2 as *const u8, 1) + //~^ ERROR evaluation of constant value failed + }; + const LHS_OUT_OF_BOUNDS: i32 = unsafe { + compare_bytes([1, 2, 3].as_ptr(), [1, 2, 3, 4].as_ptr(), 4) + //~^ ERROR evaluation of constant value failed + }; + const RHS_OUT_OF_BOUNDS: i32 = unsafe { + compare_bytes([1, 2, 3, 4].as_ptr(), [1, 2, 3].as_ptr(), 4) + //~^ ERROR evaluation of constant value failed + }; + const LHS_UNINIT: i32 = unsafe { + compare_bytes(MaybeUninit::uninit().as_ptr(), [1].as_ptr(), 1) + //~^ ERROR evaluation of constant value failed + }; + const RHS_UNINIT: i32 = unsafe { + compare_bytes([1].as_ptr(), MaybeUninit::uninit().as_ptr(), 1) + //~^ ERROR evaluation of constant value failed + }; + const WITH_PROVENANCE: i32 = unsafe { + compare_bytes([&1].as_ptr().cast(), [&2].as_ptr().cast(), std::mem::size_of::<usize>()) + //~^ ERROR evaluation of constant value failed + }; +} diff --git a/tests/ui/consts/const-compare-bytes-ub.stderr b/tests/ui/consts/const-compare-bytes-ub.stderr new file mode 100644 index 00000000000..54fafded07b --- /dev/null +++ b/tests/ui/consts/const-compare-bytes-ub.stderr @@ -0,0 +1,54 @@ +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:10:9 + | +LL | compare_bytes(0 as *const u8, 2 as *const u8, 0) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is a dangling pointer (it has no provenance) + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:14:9 + | +LL | compare_bytes(1 as *const u8, 0 as *const u8, 0) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is a dangling pointer (it has no provenance) + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:18:9 + | +LL | compare_bytes(1 as *const u8, 2 as *const u8, 1) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: 0x1[noalloc] is a dangling pointer (it has no provenance) + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:22:9 + | +LL | compare_bytes([1, 2, 3].as_ptr(), [1, 2, 3, 4].as_ptr(), 4) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: alloc6 has size 3, so pointer to 4 bytes starting at offset 0 is out-of-bounds + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:26:9 + | +LL | compare_bytes([1, 2, 3, 4].as_ptr(), [1, 2, 3].as_ptr(), 4) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: alloc13 has size 3, so pointer to 4 bytes starting at offset 0 is out-of-bounds + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:30:9 + | +LL | compare_bytes(MaybeUninit::uninit().as_ptr(), [1].as_ptr(), 1) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at alloc17[0x0..0x1], but memory is uninitialized at [0x0..0x1], and this operation requires initialized memory + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:34:9 + | +LL | compare_bytes([1].as_ptr(), MaybeUninit::uninit().as_ptr(), 1) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at alloc25[0x0..0x1], but memory is uninitialized at [0x0..0x1], and this operation requires initialized memory + +error[E0080]: evaluation of constant value failed + --> $DIR/const-compare-bytes-ub.rs:38:9 + | +LL | compare_bytes([&1].as_ptr().cast(), [&2].as_ptr().cast(), std::mem::size_of::<usize>()) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unable to turn pointer into integer + | + = help: this code performed an operation that depends on the underlying bytes representing a pointer + = help: the absolute address of a pointer is not known at compile-time, so such operations are not supported + +error: aborting due to 8 previous errors + +For more information about this error, try `rustc --explain E0080`. diff --git a/tests/ui/consts/const-compare-bytes.rs b/tests/ui/consts/const-compare-bytes.rs new file mode 100644 index 00000000000..74e29f81386 --- /dev/null +++ b/tests/ui/consts/const-compare-bytes.rs @@ -0,0 +1,27 @@ +// run-pass + +#![feature(core_intrinsics)] +#![feature(const_intrinsic_compare_bytes)] +use std::intrinsics::compare_bytes; + +fn main() { + const A: i32 = unsafe { + compare_bytes(1 as *const u8, 2 as *const u8, 0) + }; + assert_eq!(A, 0); + + const B: i32 = unsafe { + compare_bytes([1, 2].as_ptr(), [1, 3].as_ptr(), 1) + }; + assert_eq!(B, 0); + + const C: i32 = unsafe { + compare_bytes([1, 2, 9].as_ptr(), [1, 3, 8].as_ptr(), 2) + }; + assert!(C < 0); + + const D: i32 = unsafe { + compare_bytes([1, 3, 8].as_ptr(), [1, 2, 9].as_ptr(), 2) + }; + assert!(D > 0); +} diff --git a/tests/ui/proc-macro/meta-macro-hygiene.stdout b/tests/ui/proc-macro/meta-macro-hygiene.stdout index e476a8024fd..ac65ba07512 100644 --- a/tests/ui/proc-macro/meta-macro-hygiene.stdout +++ b/tests/ui/proc-macro/meta-macro-hygiene.stdout @@ -18,7 +18,7 @@ Respanned: TokenStream [Ident { ident: "$crate", span: $DIR/auxiliary/make-macro use core /* 0#1 */::prelude /* 0#1 */::rust_2018 /* 0#1 */::*; #[macro_use /* 0#1 */] extern crate core /* 0#1 */; -extern crate compiler_builtins /* 444 */ as _ /* 0#1 */; +extern crate compiler_builtins /* 445 */ as _ /* 0#1 */; // Don't load unnecessary hygiene information from std extern crate std /* 0#0 */; diff --git a/tests/ui/proc-macro/nonterminal-token-hygiene.stdout b/tests/ui/proc-macro/nonterminal-token-hygiene.stdout index 23a21004238..4031eb98a38 100644 --- a/tests/ui/proc-macro/nonterminal-token-hygiene.stdout +++ b/tests/ui/proc-macro/nonterminal-token-hygiene.stdout @@ -39,7 +39,7 @@ PRINT-BANG INPUT (DEBUG): TokenStream [ use ::core /* 0#1 */::prelude /* 0#1 */::rust_2015 /* 0#1 */::*; #[macro_use /* 0#1 */] extern crate core /* 0#2 */; -extern crate compiler_builtins /* 444 */ as _ /* 0#2 */; +extern crate compiler_builtins /* 445 */ as _ /* 0#2 */; // Don't load unnecessary hygiene information from std extern crate std /* 0#0 */; |