diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs index 6c1d4ce8f3c2b..c4eb593d2976a 100644 --- a/compiler/rustc_codegen_llvm/src/builder.rs +++ b/compiler/rustc_codegen_llvm/src/builder.rs @@ -477,6 +477,8 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { bx: &mut Builder<'a, 'll, 'tcx>, load: &'ll Value, scalar: abi::Scalar, + layout: TyAndLayout<'tcx>, + offset: Size, ) { if !scalar.is_always_valid(bx) { bx.noundef_metadata(load); @@ -488,10 +490,18 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { bx.range_metadata(load, scalar.valid_range); } } - abi::Pointer if !scalar.valid_range.contains(0) => { - bx.nonnull_metadata(load); + abi::Pointer => { + if !scalar.valid_range.contains(0) { + bx.nonnull_metadata(load); + } + + if let Some(pointee) = layout.pointee_info_at(bx, offset) { + if let Some(_) = pointee.safe { + bx.align_metadata(load, pointee.align); + } + } } - _ => {} + abi::F32 | abi::F64 => {} } } @@ -509,7 +519,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { let llval = const_llval.unwrap_or_else(|| { let load = self.load(place.layout.llvm_type(self), place.llval, place.align); if let abi::Abi::Scalar(scalar) = place.layout.abi { - scalar_load_metadata(self, load, scalar); + scalar_load_metadata(self, load, scalar, place.layout, Size::ZERO); } load }); @@ -518,17 +528,17 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> { let b_offset = a.value.size(self).align_to(b.value.align(self).abi); let pair_ty = place.layout.llvm_type(self); - let mut load = |i, scalar: abi::Scalar, align| { + let mut load = |i, scalar: abi::Scalar, layout, align, offset| { let llptr = self.struct_gep(pair_ty, place.llval, i as u64); let llty = place.layout.scalar_pair_element_llvm_type(self, i, false); let load = self.load(llty, llptr, align); - scalar_load_metadata(self, load, scalar); + scalar_load_metadata(self, load, scalar, layout, offset); self.to_immediate_scalar(load, scalar) }; OperandValue::Pair( - load(0, a, place.align), - load(1, b, place.align.restrict_for_offset(b_offset)), + load(0, a, place.layout, place.align, Size::ZERO), + load(1, b, place.layout, place.align.restrict_for_offset(b_offset), b_offset), ) } else { OperandValue::Ref(place.llval, None, place.align) @@ -1208,6 +1218,18 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> { } } + fn align_metadata(&mut self, load: &'ll Value, align: Align) { + unsafe { + let v = [self.cx.const_u64(align.bytes())]; + + llvm::LLVMSetMetadata( + load, + llvm::MD_align as c_uint, + llvm::LLVMMDNodeInContext(self.cx.llcx, v.as_ptr(), v.len() as c_uint), + ); + } + } + fn noundef_metadata(&mut self, load: &'ll Value) { unsafe { llvm::LLVMSetMetadata( diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index 6e9e0332faf60..0e1c2872ad01d 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -441,6 +441,7 @@ pub enum MetadataType { MD_nontemporal = 9, MD_mem_parallel_loop_access = 10, MD_nonnull = 11, + MD_align = 17, MD_type = 19, MD_noundef = 29, } diff --git a/src/test/codegen/loads.rs b/src/test/codegen/loads.rs index 977175a4a621d..c7444ce02fa25 100644 --- a/src/test/codegen/loads.rs +++ b/src/test/codegen/loads.rs @@ -18,21 +18,47 @@ pub enum MyBool { False, } +#[repr(align(16))] +pub struct Align16(u128); + +// CHECK: @ptr_alignment_helper({}** {{.*}}align [[PTR_ALIGNMENT:[0-9]+]] +#[no_mangle] +pub fn ptr_alignment_helper(x: &&()) {} + // CHECK-LABEL: @load_ref #[no_mangle] pub fn load_ref<'a>(x: &&'a i32) -> &'a i32 { -// Alignment of a reference itself is target dependent, so just match any alignment: -// the main thing we care about here is !nonnull and !noundef. -// CHECK: load i32*, i32** %x, align {{[0-9]+}}, !nonnull !{{[0-9]+}}, !noundef !{{[0-9]+}} +// CHECK: load i32*, i32** %x, align [[PTR_ALIGNMENT]], !nonnull !{{[0-9]+}}, !align ![[ALIGN_4_META:[0-9]+]], !noundef !{{[0-9]+}} + *x +} + +// CHECK-LABEL: @load_ref_higher_alignment +#[no_mangle] +pub fn load_ref_higher_alignment<'a>(x: &&'a Align16) -> &'a Align16 { +// CHECK: load {{%Align16|i128}}*, {{%Align16|i128}}** %x, align [[PTR_ALIGNMENT]], !nonnull !{{[0-9]+}}, !align ![[ALIGN_16_META:[0-9]+]], !noundef !{{[0-9]+}} + *x +} + +// CHECK-LABEL: @load_scalar_pair +#[no_mangle] +pub fn load_scalar_pair<'a>(x: &(&'a i32, &'a Align16)) -> (&'a i32, &'a Align16) { +// CHECK: load i32*, i32** %{{.+}}, align [[PTR_ALIGNMENT]], !nonnull !{{[0-9]+}}, !align ![[ALIGN_4_META]], !noundef !{{[0-9]+}} +// CHECK: load i64*, i64** %{{.+}}, align [[PTR_ALIGNMENT]], !nonnull !{{[0-9]+}}, !align ![[ALIGN_16_META]], !noundef !{{[0-9]+}} + *x +} + +// CHECK-LABEL: @load_raw_pointer +#[no_mangle] +pub fn load_raw_pointer<'a>(x: &*const i32) -> *const i32 { +// loaded raw pointer should not have !nonnull, !align, or !noundef metadata +// CHECK: load i32*, i32** %x, align [[PTR_ALIGNMENT]]{{$}} *x } // CHECK-LABEL: @load_box #[no_mangle] pub fn load_box<'a>(x: Box>) -> Box { -// Alignment of a box itself is target dependent, so just match any alignment: -// the main thing we care about here is !nonnull and !noundef. -// CHECK: load i32*, i32** %x, align {{[0-9]+}}, !nonnull !{{[0-9]+}}, !noundef !{{[0-9]+}} +// CHECK: load i32*, i32** %x, align [[PTR_ALIGNMENT]], !nonnull !{{[0-9]+}}, !align ![[ALIGN_4_META]], !noundef !{{[0-9]+}} *x } @@ -120,5 +146,7 @@ pub fn small_struct_alignment(x: Bytes) -> Bytes { x } -// CHECK: ![[BOOL_RANGE]] = !{i8 0, i8 2} -// CHECK: ![[NONZEROU16_RANGE]] = !{i16 1, i16 0} +// CHECK-DAG: ![[BOOL_RANGE]] = !{i8 0, i8 2} +// CHECK-DAG: ![[NONZEROU16_RANGE]] = !{i16 1, i16 0} +// CHECK-DAG: ![[ALIGN_4_META]] = !{i64 4} +// CHECK-DAG: ![[ALIGN_16_META]] = !{i64 16}