Auto merge of rust-lang#116707 - cjgillot:slice-id, r=<try>

Create an `AllocId` for `ConstValue::Slice`.

r? `@ghost`

Author: bors

compiler/rustc_codegen_cranelift/src/constant.rs

@@ -64,7 +64,7 @@ pub(crate) fn codegen_tls_ref<'tcx>(
 pub(crate) fn eval_mir_constant<'tcx>(
     fx: &FunctionCx<'_, '_, 'tcx>,
     constant: &ConstOperand<'tcx>,
-) -> (ConstValue<'tcx>, Ty<'tcx>) {
+) -> (ConstValue, Ty<'tcx>) {
     let cv = fx.monomorphize(constant.const_);
     // This cannot fail because we checked all required_consts in advance.
     let val = cv
@@ -83,7 +83,7 @@ pub(crate) fn codegen_constant_operand<'tcx>(
 
 pub(crate) fn codegen_const_value<'tcx>(
     fx: &mut FunctionCx<'_, '_, 'tcx>,
-    const_val: ConstValue<'tcx>,
+    const_val: ConstValue,
     ty: Ty<'tcx>,
 ) -> CValue<'tcx> {
     let layout = fx.layout_of(ty);
@@ -183,8 +183,7 @@ pub(crate) fn codegen_const_value<'tcx>(
                 .offset_i64(fx, i64::try_from(offset.bytes()).unwrap()),
             layout,
         ),
-        ConstValue::Slice { data, meta } => {
-            let alloc_id = fx.tcx.reserve_and_set_memory_alloc(data);
+        ConstValue::Slice { alloc_id, meta } => {
             let ptr = pointer_for_allocation(fx, alloc_id).get_addr(fx);
             let len = fx.bcx.ins().iconst(fx.pointer_type, meta as i64);
             CValue::by_val_pair(ptr, len, layout)
@@ -430,7 +429,7 @@ fn define_all_allocs(tcx: TyCtxt<'_>, module: &mut dyn Module, cx: &mut Constant
 pub(crate) fn mir_operand_get_const_val<'tcx>(
     fx: &FunctionCx<'_, '_, 'tcx>,
     operand: &Operand<'tcx>,
-) -> Option<ConstValue<'tcx>> {
+) -> Option<ConstValue> {
     match operand {
         Operand::Constant(const_) => Some(eval_mir_constant(fx, const_).0),
         // FIXME(rust-lang/rust#85105): Casts like `IMM8 as u32` result in the const being stored

compiler/rustc_codegen_llvm/src/common.rs

@@ -8,7 +8,6 @@ use crate::value::Value;
 
 use rustc_ast::Mutability;
 use rustc_codegen_ssa::traits::*;
-use rustc_data_structures::stable_hasher::{Hash128, HashStable, StableHasher};
 use rustc_hir::def_id::DefId;
 use rustc_middle::bug;
 use rustc_middle::mir::interpret::{ConstAllocation, GlobalAlloc, Scalar};
@@ -254,14 +253,6 @@ impl<'ll, 'tcx> ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                             Mutability::Mut => self.static_addr_of_mut(init, alloc.align, None),
                             _ => self.static_addr_of(init, alloc.align, None),
                         };
-                        if !self.sess().fewer_names() && llvm::get_value_name(value).is_empty() {
-                            let hash = self.tcx.with_stable_hashing_context(|mut hcx| {
-                                let mut hasher = StableHasher::new();
-                                alloc.hash_stable(&mut hcx, &mut hasher);
-                                hasher.finish::<Hash128>()
-                            });
-                            llvm::set_value_name(value, format!("alloc_{hash:032x}").as_bytes());
-                        }
                         (value, AddressSpace::DATA)
                     }
                     GlobalAlloc::Function(fn_instance) => (

compiler/rustc_codegen_ssa/src/common.rs

@@ -194,7 +194,7 @@ pub fn shift_mask_val<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 pub fn asm_const_to_str<'tcx>(
     tcx: TyCtxt<'tcx>,
     sp: Span,
-    const_value: mir::ConstValue<'tcx>,
+    const_value: mir::ConstValue,
     ty_and_layout: TyAndLayout<'tcx>,
 ) -> String {
     let mir::ConstValue::Scalar(scalar) = const_value else {

compiler/rustc_codegen_ssa/src/mir/constant.rs

@@ -20,7 +20,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         OperandRef::from_const(bx, val, ty)
     }
 
-    pub fn eval_mir_constant(&self, constant: &mir::ConstOperand<'tcx>) -> mir::ConstValue<'tcx> {
+    pub fn eval_mir_constant(&self, constant: &mir::ConstOperand<'tcx>) -> mir::ConstValue {
         // `MirUsedCollector` visited all constants before codegen began, so if we got here there
         // can be no more constants that fail to evaluate.
         self.monomorphize(constant.const_)

compiler/rustc_codegen_ssa/src/mir/operand.rs

@@ -86,7 +86,7 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
 
     pub fn from_const<Bx: BuilderMethods<'a, 'tcx, Value = V>>(
         bx: &mut Bx,
-        val: mir::ConstValue<'tcx>,
+        val: mir::ConstValue,
         ty: Ty<'tcx>,
     ) -> Self {
         let layout = bx.layout_of(ty);
@@ -100,14 +100,11 @@ impl<'a, 'tcx, V: CodegenObject> OperandRef<'tcx, V> {
                 OperandValue::Immediate(llval)
             }
             ConstValue::ZeroSized => return OperandRef::zero_sized(layout),
-            ConstValue::Slice { data, meta } => {
+            ConstValue::Slice { alloc_id, meta } => {
                 let Abi::ScalarPair(a_scalar, _) = layout.abi else {
                     bug!("from_const: invalid ScalarPair layout: {:#?}", layout);
                 };
-                let a = Scalar::from_pointer(
-                    Pointer::new(bx.tcx().reserve_and_set_memory_alloc(data), Size::ZERO),
-                    &bx.tcx(),
-                );
+                let a = Scalar::from_pointer(Pointer::new(alloc_id, Size::ZERO), &bx.tcx());
                 let a_llval = bx.scalar_to_backend(
                     a,
                     a_scalar,

compiler/rustc_const_eval/src/const_eval/eval_queries.rs

@@ -109,7 +109,7 @@ pub(super) fn mk_eval_cx<'mir, 'tcx>(
 pub(super) fn op_to_const<'tcx>(
     ecx: &CompileTimeEvalContext<'_, 'tcx>,
     op: &OpTy<'tcx>,
-) -> ConstValue<'tcx> {
+) -> ConstValue {
     // Handle ZST consistently and early.
     if op.layout.is_zst() {
         return ConstValue::ZeroSized;
@@ -167,10 +167,9 @@ pub(super) fn op_to_const<'tcx>(
                 // We know `offset` is relative to the allocation, so we can use `into_parts`.
                 let (alloc_id, offset) = a.to_pointer(ecx).expect(msg).into_parts();
                 let alloc_id = alloc_id.expect(msg);
-                let data = ecx.tcx.global_alloc(alloc_id).unwrap_memory();
                 assert!(offset == abi::Size::ZERO, "{}", msg);
                 let meta = b.to_target_usize(ecx).expect(msg);
-                ConstValue::Slice { data, meta }
+                ConstValue::Slice { alloc_id, meta }
             }
             Immediate::Uninit => bug!("`Uninit` is not a valid value for {}", op.layout.ty),
         },
@@ -182,7 +181,7 @@ pub(crate) fn turn_into_const_value<'tcx>(
     tcx: TyCtxt<'tcx>,
     constant: ConstAlloc<'tcx>,
     key: ty::ParamEnvAnd<'tcx, GlobalId<'tcx>>,
-) -> ConstValue<'tcx> {
+) -> ConstValue {
     let cid = key.value;
     let def_id = cid.instance.def.def_id();
     let is_static = tcx.is_static(def_id);
@@ -211,7 +210,7 @@ pub(crate) fn turn_into_const_value<'tcx>(
 pub fn eval_to_const_value_raw_provider<'tcx>(
     tcx: TyCtxt<'tcx>,
     key: ty::ParamEnvAnd<'tcx, GlobalId<'tcx>>,
-) -> ::rustc_middle::mir::interpret::EvalToConstValueResult<'tcx> {
+) -> ::rustc_middle::mir::interpret::EvalToConstValueResult {
     // see comment in eval_to_allocation_raw_provider for what we're doing here
     if key.param_env.reveal() == Reveal::All {
         let mut key = key;

compiler/rustc_const_eval/src/const_eval/mod.rs

@@ -23,7 +23,7 @@ pub(crate) use valtrees::{const_to_valtree_inner, valtree_to_const_value};
 pub(crate) fn const_caller_location(
     tcx: TyCtxt<'_>,
     (file, line, col): (Symbol, u32, u32),
-) -> mir::ConstValue<'_> {
+) -> mir::ConstValue {
     trace!("const_caller_location: {}:{}:{}", file, line, col);
     let mut ecx = mk_eval_cx(tcx, DUMMY_SP, ty::ParamEnv::reveal_all(), CanAccessStatics::No);
 
@@ -88,7 +88,7 @@ pub(crate) fn eval_to_valtree<'tcx>(
 #[instrument(skip(tcx), level = "debug")]
 pub(crate) fn try_destructure_mir_constant_for_diagnostics<'tcx>(
     tcx: TyCtxtAt<'tcx>,
-    val: mir::ConstValue<'tcx>,
+    val: mir::ConstValue,
     ty: Ty<'tcx>,
 ) -> Option<mir::DestructuredConstant<'tcx>> {
     let param_env = ty::ParamEnv::reveal_all();

compiler/rustc_const_eval/src/const_eval/valtrees.rs

@@ -207,7 +207,7 @@ pub fn valtree_to_const_value<'tcx>(
     tcx: TyCtxt<'tcx>,
     param_env_ty: ty::ParamEnvAnd<'tcx, Ty<'tcx>>,
     valtree: ty::ValTree<'tcx>,
-) -> mir::ConstValue<'tcx> {
+) -> mir::ConstValue {
     // Basic idea: We directly construct `Scalar` values from trivial `ValTree`s
     // (those for constants with type bool, int, uint, float or char).
     // For all other types we create an `MPlace` and fill that by walking

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -5,7 +5,7 @@
 use rustc_hir::def_id::DefId;
 use rustc_middle::mir::{
     self,
-    interpret::{Allocation, ConstAllocation, GlobalId, InterpResult, PointerArithmetic, Scalar},
+    interpret::{AllocId, GlobalId, InterpResult, PointerArithmetic, Scalar},
     BinOp, ConstValue, NonDivergingIntrinsic,
 };
 use rustc_middle::ty;
@@ -42,10 +42,11 @@ fn numeric_intrinsic<Prov>(name: Symbol, bits: u128, kind: Primitive) -> Scalar<
 }
 
 /// Directly returns an `Allocation` containing an absolute path representation of the given type.
-pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ConstAllocation<'tcx> {
+pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> (AllocId, u64) {
     let path = crate::util::type_name(tcx, ty);
-    let alloc = Allocation::from_bytes_byte_aligned_immutable(path.into_bytes());
-    tcx.mk_const_alloc(alloc)
+    let bytes = path.into_bytes();
+    let len = bytes.len().try_into().unwrap();
+    (tcx.allocate_bytes(bytes), len)
 }
 
 /// The logic for all nullary intrinsics is implemented here. These intrinsics don't get evaluated
@@ -55,14 +56,14 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>(
     param_env: ty::ParamEnv<'tcx>,
     def_id: DefId,
     args: GenericArgsRef<'tcx>,
-) -> InterpResult<'tcx, ConstValue<'tcx>> {
+) -> InterpResult<'tcx, ConstValue> {
     let tp_ty = args.type_at(0);
     let name = tcx.item_name(def_id);
     Ok(match name {
         sym::type_name => {
             ensure_monomorphic_enough(tcx, tp_ty)?;
-            let alloc = alloc_type_name(tcx, tp_ty);
-            ConstValue::Slice { data: alloc, meta: alloc.inner().size().bytes() }
+            let (alloc_id, len) = alloc_type_name(tcx, tp_ty);
+            ConstValue::Slice { alloc_id, meta: len }
         }
         sym::needs_drop => {
             ensure_monomorphic_enough(tcx, tp_ty)?;

compiler/rustc_const_eval/src/interpret/operand.rs

@@ -722,7 +722,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
     pub(crate) fn const_val_to_op(
         &self,
-        val_val: mir::ConstValue<'tcx>,
+        val_val: mir::ConstValue,
         ty: Ty<'tcx>,
         layout: Option<TyAndLayout<'tcx>>,
     ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> {
@@ -743,10 +743,10 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             }
             mir::ConstValue::Scalar(x) => Operand::Immediate(adjust_scalar(x)?.into()),
             mir::ConstValue::ZeroSized => Operand::Immediate(Immediate::Uninit),
-            mir::ConstValue::Slice { data, meta } => {
+            mir::ConstValue::Slice { alloc_id, meta } => {
                 // We rely on mutability being set correctly in `data` to prevent writes
                 // where none should happen.
-                let ptr = Pointer::new(self.tcx.reserve_and_set_memory_alloc(data), Size::ZERO);
+                let ptr = Pointer::new(alloc_id, Size::ZERO);
                 Operand::Immediate(Immediate::new_slice(
                     self.global_base_pointer(ptr)?.into(),
                     meta,