diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/abi.rs | 65 |
1 files changed, 47 insertions, 18 deletions
diff --git a/compiler/rustc_codegen_llvm/src/abi.rs b/compiler/rustc_codegen_llvm/src/abi.rs index d9393ffe534..854e3ccc21b 100644 --- a/compiler/rustc_codegen_llvm/src/abi.rs +++ b/compiler/rustc_codegen_llvm/src/abi.rs @@ -1,6 +1,7 @@ use crate::builder::Builder; use crate::context::CodegenCx; use crate::llvm::{self, AttributePlace}; +use crate::llvm_util; use crate::type_::Type; use crate::type_of::LayoutLlvmExt; use crate::value::Value; @@ -41,12 +42,29 @@ impl ArgAttributeExt for ArgAttribute { } pub trait ArgAttributesExt { - fn apply_attrs_to_llfn(&self, idx: AttributePlace, llfn: &Value); - fn apply_attrs_to_callsite(&self, idx: AttributePlace, callsite: &Value); + fn apply_attrs_to_llfn(&self, idx: AttributePlace, cx: &CodegenCx<'_, '_>, llfn: &Value); + fn apply_attrs_to_callsite( + &self, + idx: AttributePlace, + cx: &CodegenCx<'_, '_>, + callsite: &Value, + ); +} + +fn should_use_mutable_noalias(cx: &CodegenCx<'_, '_>) -> bool { + // LLVM prior to version 12 has known miscompiles in the presence of + // noalias attributes (see #54878). Only enable mutable noalias by + // default for versions we believe to be safe. + cx.tcx + .sess + .opts + .debugging_opts + .mutable_noalias + .unwrap_or_else(|| llvm_util::get_version() >= (12, 0, 0)) } impl ArgAttributesExt for ArgAttributes { - fn apply_attrs_to_llfn(&self, idx: AttributePlace, llfn: &Value) { + fn apply_attrs_to_llfn(&self, idx: AttributePlace, cx: &CodegenCx<'_, '_>, llfn: &Value) { let mut regular = self.regular; unsafe { let deref = self.pointee_size.bytes(); @@ -62,6 +80,9 @@ impl ArgAttributesExt for ArgAttributes { llvm::LLVMRustAddAlignmentAttr(llfn, idx.as_uint(), align.bytes() as u32); } regular.for_each_kind(|attr| attr.apply_llfn(idx, llfn)); + if regular.contains(ArgAttribute::NoAliasMutRef) && should_use_mutable_noalias(cx) { + llvm::Attribute::NoAlias.apply_llfn(idx, llfn); + } match self.arg_ext { ArgExtension::None => {} ArgExtension::Zext => { @@ -74,7 +95,12 @@ impl ArgAttributesExt for ArgAttributes { } } - fn apply_attrs_to_callsite(&self, idx: AttributePlace, callsite: &Value) { + fn apply_attrs_to_callsite( + &self, + idx: AttributePlace, + cx: &CodegenCx<'_, '_>, + callsite: &Value, + ) { let mut regular = self.regular; unsafe { let deref = self.pointee_size.bytes(); @@ -98,6 +124,9 @@ impl ArgAttributesExt for ArgAttributes { ); } regular.for_each_kind(|attr| attr.apply_callsite(idx, callsite)); + if regular.contains(ArgAttribute::NoAliasMutRef) && should_use_mutable_noalias(cx) { + llvm::Attribute::NoAlias.apply_callsite(idx, callsite); + } match self.arg_ext { ArgExtension::None => {} ArgExtension::Zext => { @@ -419,13 +448,13 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> { let mut i = 0; let mut apply = |attrs: &ArgAttributes| { - attrs.apply_attrs_to_llfn(llvm::AttributePlace::Argument(i), llfn); + attrs.apply_attrs_to_llfn(llvm::AttributePlace::Argument(i), cx, llfn); i += 1; i - 1 }; match self.ret.mode { PassMode::Direct(ref attrs) => { - attrs.apply_attrs_to_llfn(llvm::AttributePlace::ReturnValue, llfn); + attrs.apply_attrs_to_llfn(llvm::AttributePlace::ReturnValue, cx, llfn); } PassMode::Indirect { ref attrs, extra_attrs: _, on_stack } => { assert!(!on_stack); @@ -480,18 +509,18 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> { // FIXME(wesleywiser, eddyb): We should apply `nounwind` and `noreturn` as appropriate to this callsite. let mut i = 0; - let mut apply = |attrs: &ArgAttributes| { - attrs.apply_attrs_to_callsite(llvm::AttributePlace::Argument(i), callsite); + let mut apply = |cx: &CodegenCx<'_, '_>, attrs: &ArgAttributes| { + attrs.apply_attrs_to_callsite(llvm::AttributePlace::Argument(i), cx, callsite); i += 1; i - 1 }; match self.ret.mode { PassMode::Direct(ref attrs) => { - attrs.apply_attrs_to_callsite(llvm::AttributePlace::ReturnValue, callsite); + attrs.apply_attrs_to_callsite(llvm::AttributePlace::ReturnValue, &bx.cx, callsite); } PassMode::Indirect { ref attrs, extra_attrs: _, on_stack } => { assert!(!on_stack); - let i = apply(attrs); + let i = apply(bx.cx, attrs); unsafe { llvm::LLVMRustAddStructRetCallSiteAttr( callsite, @@ -517,12 +546,12 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> { } for arg in &self.args { if arg.pad.is_some() { - apply(&ArgAttributes::new()); + apply(bx.cx, &ArgAttributes::new()); } match arg.mode { PassMode::Ignore => {} PassMode::Indirect { ref attrs, extra_attrs: None, on_stack: true } => { - let i = apply(attrs); + let i = apply(bx.cx, attrs); unsafe { llvm::LLVMRustAddByValCallSiteAttr( callsite, @@ -533,22 +562,22 @@ impl<'tcx> FnAbiLlvmExt<'tcx> for FnAbi<'tcx, Ty<'tcx>> { } PassMode::Direct(ref attrs) | PassMode::Indirect { ref attrs, extra_attrs: None, on_stack: false } => { - apply(attrs); + apply(bx.cx, attrs); } PassMode::Indirect { ref attrs, extra_attrs: Some(ref extra_attrs), on_stack: _, } => { - apply(attrs); - apply(extra_attrs); + apply(bx.cx, attrs); + apply(bx.cx, extra_attrs); } PassMode::Pair(ref a, ref b) => { - apply(a); - apply(b); + apply(bx.cx, a); + apply(bx.cx, b); } PassMode::Cast(_) => { - apply(&ArgAttributes::new()); + apply(bx.cx, &ArgAttributes::new()); } } } |