diff options
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/traits/builder.rs | 23 | ||||
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/traits/intrinsic.rs | 8 | ||||
| -rw-r--r-- | compiler/rustc_middle/src/ty/instance.rs | 14 |
3 files changed, 35 insertions, 10 deletions
diff --git a/compiler/rustc_codegen_ssa/src/traits/builder.rs b/compiler/rustc_codegen_ssa/src/traits/builder.rs index 1f266514f34..bb53a8b5d28 100644 --- a/compiler/rustc_codegen_ssa/src/traits/builder.rs +++ b/compiler/rustc_codegen_ssa/src/traits/builder.rs @@ -554,12 +554,33 @@ pub trait BuilderMethods<'a, 'tcx>: /// Called for `StorageDead` fn lifetime_end(&mut self, ptr: Self::Value, size: Size); + /// "Finally codegen the call" + /// + /// ## Arguments + /// + /// The `fn_attrs`, `fn_abi`, and `instance` arguments are Options because they are advisory. + /// They relate to optional codegen enhancements like LLVM CFI, and do not affect ABI per se. + /// Any ABI-related transformations should be handled by different, earlier stages of codegen. + /// For instance, in the caller of `BuilderMethods::call`. + /// + /// This means that a codegen backend which disregards `fn_attrs`, `fn_abi`, and `instance` + /// should still do correct codegen, and code should not be miscompiled if they are omitted. + /// It is not a miscompilation in this sense if it fails to run under CFI, other sanitizers, or + /// in the context of other compiler-enhanced security features. + /// + /// The typical case that they are None is during the codegen of intrinsics and lang-items, + /// as those are "fake functions" with only a trivial ABI if any, et cetera. + /// + /// ## Return + /// + /// Must return the value the function will return so it can be written to the destination, + /// assuming the function does not explicitly pass the destination as a pointer in `args`. fn call( &mut self, llty: Self::Type, fn_attrs: Option<&CodegenFnAttrs>, fn_abi: Option<&FnAbi<'tcx, Ty<'tcx>>>, - llfn: Self::Value, + fn_val: Self::Value, args: &[Self::Value], funclet: Option<&Self::Funclet>, instance: Option<Instance<'tcx>>, diff --git a/compiler/rustc_codegen_ssa/src/traits/intrinsic.rs b/compiler/rustc_codegen_ssa/src/traits/intrinsic.rs index 7d0c6be4c65..c5ecf43046c 100644 --- a/compiler/rustc_codegen_ssa/src/traits/intrinsic.rs +++ b/compiler/rustc_codegen_ssa/src/traits/intrinsic.rs @@ -6,16 +6,22 @@ use crate::mir::operand::OperandRef; use crate::mir::place::PlaceRef; pub trait IntrinsicCallBuilderMethods<'tcx>: BackendTypes { + /// Higher-level interface to emitting calls to intrinsics + /// /// Remember to add all intrinsics here, in `compiler/rustc_hir_analysis/src/check/mod.rs`, /// and in `library/core/src/intrinsics.rs`; if you need access to any LLVM intrinsics, /// add them to `compiler/rustc_codegen_llvm/src/context.rs`. /// Returns `Err` if another instance should be called instead. This is used to invoke /// intrinsic default bodies in case an intrinsic is not implemented by the backend. + /// + /// NOTE: allowed to call [`BuilderMethods::call`] + /// + /// [`BuilderMethods::call`]: super::builder::BuilderMethods::call fn codegen_intrinsic_call( &mut self, instance: ty::Instance<'tcx>, args: &[OperandRef<'tcx, Self::Value>], - result: PlaceRef<'tcx, Self::Value>, + result_dest: PlaceRef<'tcx, Self::Value>, span: Span, ) -> Result<(), ty::Instance<'tcx>>; diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs index 21b7500e46f..d5767ca3786 100644 --- a/compiler/rustc_middle/src/ty/instance.rs +++ b/compiler/rustc_middle/src/ty/instance.rs @@ -991,18 +991,16 @@ fn needs_fn_once_adapter_shim( Ok(false) } (ty::ClosureKind::Fn, ty::ClosureKind::FnMut) => { - // The closure fn `llfn` is a `fn(&self, ...)`. We want a - // `fn(&mut self, ...)`. In fact, at codegen time, these are - // basically the same thing, so we can just return llfn. + // The closure fn is a `fn(&self, ...)`, but we want a `fn(&mut self, ...)`. + // At codegen time, these are basically the same, so we can just return the closure. Ok(false) } (ty::ClosureKind::Fn | ty::ClosureKind::FnMut, ty::ClosureKind::FnOnce) => { - // The closure fn `llfn` is a `fn(&self, ...)` or `fn(&mut - // self, ...)`. We want a `fn(self, ...)`. We can produce - // this by doing something like: + // The closure fn is a `fn(&self, ...)` or `fn(&mut self, ...)`, but + // we want a `fn(self, ...)`. We can produce this by doing something like: // - // fn call_once(self, ...) { call_mut(&self, ...) } - // fn call_once(mut self, ...) { call_mut(&mut self, ...) } + // fn call_once(self, ...) { Fn::call(&self, ...) } + // fn call_once(mut self, ...) { FnMut::call_mut(&mut self, ...) } // // These are both the same at codegen time. Ok(true) |