Split out the stable part of smir into its own crate to prevent accidental usage of forever unstable things

Author: oli-obk

Cargo.lock

@@ -3257,6 +3257,7 @@ dependencies = [
  "rustc_driver",
  "rustc_driver_impl",
  "rustc_smir",
+ "stable_mir",
 ]
 
 [[package]]
@@ -4421,7 +4422,7 @@ dependencies = [
  "rustc_session",
  "rustc_span",
  "rustc_target",
- "scoped-tls",
+ "stable_mir",
  "tracing",
 ]
 
@@ -4958,6 +4959,14 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a8f112729512f8e442d81f95a8a7ddf2b7c6b8a1a6f509a95864142b30cab2d3"
 
+[[package]]
+name = "stable_mir"
+version = "0.1.0-preview"
+dependencies = [
+ "scoped-tls",
+ "tracing",
+]
+
 [[package]]
 name = "stacker"
 version = "0.1.15"

compiler/rustc/Cargo.toml

@@ -13,6 +13,7 @@ rustc_codegen_ssa = { path = "../rustc_codegen_ssa" }
 # Make sure rustc_smir ends up in the sysroot, because this
 # crate is intended to be used by stable MIR consumers, which are not in-tree
 rustc_smir = { path = "../rustc_smir" }
+stable_mir = { path = "../stable_mir" }
 
 [dependencies.jemalloc-sys]
 version = "0.5.0"

compiler/rustc_smir/Cargo.toml

@@ -4,24 +4,14 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
-# Use optional dependencies for rustc_* in order to support building this crate separately.
-rustc_hir = { path = "../rustc_hir", optional = true }
-rustc_middle = { path = "../rustc_middle", optional = true }
-rustc_span = { path = "../rustc_span", optional = true }
-rustc_target = { path = "../rustc_target", optional = true }
-rustc_driver = { path = "../rustc_driver", optional = true }
-rustc_interface = { path = "../rustc_interface", optional = true}
-rustc_session = {path = "../rustc_session", optional = true}
+rustc_hir = { path = "../rustc_hir" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_span = { path = "../rustc_span" }
+rustc_target = { path = "../rustc_target" }
+rustc_driver = { path = "../rustc_driver" }
+rustc_interface = { path = "../rustc_interface" }
+rustc_session = {path = "../rustc_session" }
 tracing = "0.1"
-scoped-tls = "1.0"
+stable_mir = {path = "../stable_mir" }
 
 [features]
-default = [
-    "rustc_hir",
-    "rustc_middle",
-    "rustc_span",
-    "rustc_target",
-    "rustc_driver",
-    "rustc_interface",
-    "rustc_session",
-]

compiler/rustc_smir/src/lib.rs

@@ -10,26 +10,12 @@
     html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/",
     test(attr(allow(unused_variables), deny(warnings)))
 )]
-#![cfg_attr(not(feature = "default"), feature(rustc_private))]
+#![feature(rustc_private)]
 #![feature(ptr_metadata)]
 #![feature(type_alias_impl_trait)] // Used to define opaque types.
 #![feature(intra_doc_pointers)]
 
-// Declare extern rustc_* crates to enable building this crate separately from the compiler.
-#[cfg(not(feature = "default"))]
-extern crate rustc_hir;
-#[cfg(not(feature = "default"))]
-extern crate rustc_middle;
-#[cfg(not(feature = "default"))]
-extern crate rustc_span;
-#[cfg(not(feature = "default"))]
-extern crate rustc_target;
-
 pub mod rustc_internal;
-pub mod stable_mir;
 
 // Make this module private for now since external users should not call these directly.
 mod rustc_smir;
-
-#[macro_use]
-extern crate scoped_tls;

compiler/rustc_smir/src/rustc_internal/mod.rs

@@ -6,14 +6,14 @@
 use std::ops::{ControlFlow, Index};
 
 use crate::rustc_internal;
-use crate::stable_mir::CompilerError;
-use crate::{rustc_smir::Tables, stable_mir};
+use crate::rustc_smir::Tables;
 use rustc_driver::{Callbacks, Compilation, RunCompiler};
 use rustc_interface::{interface, Queries};
 use rustc_middle::mir::interpret::AllocId;
 use rustc_middle::ty::TyCtxt;
 pub use rustc_span::def_id::{CrateNum, DefId};
 use rustc_span::Span;
+use stable_mir::CompilerError;
 
 impl<'tcx> Index<stable_mir::DefId> for Tables<'tcx> {
     type Output = DefId;
@@ -129,7 +129,7 @@ pub fn crate_num(item: &stable_mir::Crate) -> CrateNum {
 }
 
 pub fn run(tcx: TyCtxt<'_>, f: impl FnOnce()) {
-    crate::stable_mir::run(
+    stable_mir::run(
         Tables { tcx, def_ids: vec![], alloc_ids: vec![], spans: vec![], types: vec![] },
         f,
     );

compiler/rustc_smir/src/rustc_smir/alloc.rs

@@ -3,11 +3,9 @@ use rustc_middle::mir::{
     ConstValue,
 };
 
-use crate::{
-    rustc_smir::{Stable, Tables},
-    stable_mir::mir::Mutability,
-    stable_mir::ty::{Allocation, ProvenanceMap},
-};
+use crate::rustc_smir::{Stable, Tables};
+use stable_mir::mir::Mutability;
+use stable_mir::ty::{Allocation, ProvenanceMap};
 
 /// Creates new empty `Allocation` from given `Align`.
 fn new_empty_allocation(align: rustc_target::abi::Align) -> Allocation {

compiler/rustc_smir/src/rustc_smir/mod.rs

@@ -7,19 +7,16 @@
 //!
 //! For now, we are developing everything inside `rustc`, thus, we keep this module private.
 
-use crate::stable_mir::mir::{CopyNonOverlapping, UserTypeProjection, VariantIdx};
-use crate::stable_mir::ty::{
-    FloatTy, GenericParamDef, IntTy, Movability, RigidTy, Span, TyKind, UintTy,
-};
-use crate::stable_mir::{self, opaque, CompilerError, Context};
 use hir::def::DefKind;
 use rustc_hir as hir;
 use rustc_middle::mir;
 use rustc_middle::mir::interpret::{alloc_range, AllocId};
 use rustc_middle::ty::{self, Ty, TyCtxt, Variance};
 use rustc_span::def_id::{CrateNum, DefId, LOCAL_CRATE};
-use rustc_span::ErrorGuaranteed;
 use rustc_target::abi::FieldIdx;
+use stable_mir::mir::{CopyNonOverlapping, UserTypeProjection, VariantIdx};
+use stable_mir::ty::{FloatTy, GenericParamDef, IntTy, Movability, RigidTy, Span, TyKind, UintTy};
+use stable_mir::{self, opaque, Context};
 use tracing::debug;
 
 mod alloc;
@@ -112,7 +109,7 @@ impl<'tcx> Context for Tables<'tcx> {
         }
     }
 
-    fn ty_kind(&mut self, ty: crate::stable_mir::ty::Ty) -> TyKind {
+    fn ty_kind(&mut self, ty: stable_mir::ty::Ty) -> TyKind {
         self.types[ty.0].clone().stable(self)
     }
 
@@ -1517,12 +1514,6 @@ impl<'tcx> Stable<'tcx> for rustc_span::Span {
     }
 }
 
-impl<T> From<ErrorGuaranteed> for CompilerError<T> {
-    fn from(_error: ErrorGuaranteed) -> Self {
-        CompilerError::CompilationFailed
-    }
-}
-
 impl<'tcx> Stable<'tcx> for DefKind {
     type T = stable_mir::DefKind;
 

compiler/stable_mir/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "stable_mir"
+version = "0.1.0-preview"
+edition = "2021"
+
+[dependencies]
+tracing = "0.1"
+scoped-tls = "1.0"