//! Handling of `static`s, `const`s and promoted allocations
-use rustc_span::DUMMY_SP;
-
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_errors::ErrorReported;
use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
use rustc_middle::mir::interpret::{
- read_target_uint, AllocId, Allocation, ConstValue, ErrorHandled, GlobalAlloc, Pointer, Scalar,
+ read_target_uint, AllocId, ConstAllocation, ConstValue, ErrorHandled, GlobalAlloc, Scalar,
};
use rustc_middle::ty::ConstKind;
+use rustc_span::DUMMY_SP;
use cranelift_codegen::ir::GlobalValueData;
use cranelift_module::*;
-use crate::{prelude::*, CodegenCx};
+use crate::prelude::*;
pub(crate) struct ConstantCx {
todo: Vec<TodoItem>,
ConstantKind::Ty(ct) => ct,
ConstantKind::Val(..) => continue,
};
- match const_.val {
+ match const_.val() {
ConstKind::Value(_) => {}
ConstKind::Unevaluated(unevaluated) => {
if let Err(err) =
{
all_constants_ok = false;
match err {
- ErrorHandled::Reported(ErrorReported) | ErrorHandled::Linted => {
+ ErrorHandled::Reported(_) | ErrorHandled::Linted => {
fx.tcx.sess.span_err(constant.span, "erroneous constant encountered");
}
ErrorHandled::TooGeneric => {
all_constants_ok
}
-pub(crate) fn codegen_static(cx: &mut CodegenCx<'_, '_>, def_id: DefId) {
+pub(crate) fn codegen_static(tcx: TyCtxt<'_>, module: &mut dyn Module, def_id: DefId) {
let mut constants_cx = ConstantCx::new();
constants_cx.todo.push(TodoItem::Static(def_id));
- constants_cx.finalize(cx.tcx, &mut *cx.module);
+ constants_cx.finalize(tcx, module);
}
pub(crate) fn codegen_tls_ref<'tcx>(
def_id: DefId,
layout: TyAndLayout<'tcx>,
) -> CValue<'tcx> {
- let data_id = data_id_for_static(fx.tcx, fx.cx.module, def_id, false);
- let local_data_id = fx.cx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ let data_id = data_id_for_static(fx.tcx, fx.module, def_id, false);
+ let local_data_id = fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
if fx.clif_comments.enabled() {
fx.add_comment(local_data_id, format!("tls {:?}", def_id));
}
def_id: DefId,
layout: TyAndLayout<'tcx>,
) -> CPlace<'tcx> {
- let data_id = data_id_for_static(fx.tcx, fx.cx.module, def_id, false);
- let local_data_id = fx.cx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ let data_id = data_id_for_static(fx.tcx, fx.module, def_id, false);
+ let local_data_id = fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
if fx.clif_comments.enabled() {
fx.add_comment(local_data_id, format!("{:?}", def_id));
}
ConstantKind::Ty(ct) => ct,
ConstantKind::Val(val, ty) => return codegen_const_value(fx, val, ty),
};
- let const_val = match const_.val {
+ let const_val = match const_.val() {
ConstKind::Value(const_val) => const_val,
ConstKind::Unevaluated(ty::Unevaluated { def, substs, promoted })
if fx.tcx.is_static(def.did) =>
assert!(substs.is_empty());
assert!(promoted.is_none());
- return codegen_static_ref(fx, def.did, fx.layout_of(const_.ty)).to_cvalue(fx);
+ return codegen_static_ref(fx, def.did, fx.layout_of(const_.ty())).to_cvalue(fx);
}
ConstKind::Unevaluated(unevaluated) => {
match fx.tcx.const_eval_resolve(ParamEnv::reveal_all(), unevaluated, None) {
| ConstKind::Error(_) => unreachable!("{:?}", const_),
};
- codegen_const_value(fx, const_val, const_.ty)
+ codegen_const_value(fx, const_val, const_.ty())
}
pub(crate) fn codegen_const_value<'tcx>(
}
match const_val {
- ConstValue::Scalar(x) => {
- if fx.clif_type(layout.ty).is_none() {
- let (size, align) = (layout.size, layout.align.pref);
- let mut alloc = Allocation::from_bytes(
- std::iter::repeat(0).take(size.bytes_usize()).collect::<Vec<u8>>(),
- align,
- );
- let ptr = Pointer::new(AllocId(!0), Size::ZERO); // The alloc id is never used
- alloc.write_scalar(fx, ptr, x.into(), size).unwrap();
- let alloc = fx.tcx.intern_const_alloc(alloc);
- return CValue::by_ref(pointer_for_allocation(fx, alloc), layout);
- }
-
- match x {
- Scalar::Int(int) => CValue::const_val(fx, layout, int),
- Scalar::Ptr(ptr) => {
- let alloc_kind = fx.tcx.get_global_alloc(ptr.alloc_id);
- let base_addr = match alloc_kind {
- Some(GlobalAlloc::Memory(alloc)) => {
- fx.constants_cx.todo.push(TodoItem::Alloc(ptr.alloc_id));
- let data_id = data_id_for_alloc_id(
- &mut fx.constants_cx,
- fx.cx.module,
- ptr.alloc_id,
- alloc.mutability,
- );
- let local_data_id =
- fx.cx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
- if fx.clif_comments.enabled() {
- fx.add_comment(local_data_id, format!("{:?}", ptr.alloc_id));
- }
- fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ ConstValue::Scalar(x) => match x {
+ Scalar::Int(int) => {
+ if fx.clif_type(layout.ty).is_some() {
+ return CValue::const_val(fx, layout, int);
+ } else {
+ let raw_val = int.to_bits(int.size()).unwrap();
+ let val = match int.size().bytes() {
+ 1 => fx.bcx.ins().iconst(types::I8, raw_val as i64),
+ 2 => fx.bcx.ins().iconst(types::I16, raw_val as i64),
+ 4 => fx.bcx.ins().iconst(types::I32, raw_val as i64),
+ 8 => fx.bcx.ins().iconst(types::I64, raw_val as i64),
+ 16 => {
+ let lsb = fx.bcx.ins().iconst(types::I64, raw_val as u64 as i64);
+ let msb =
+ fx.bcx.ins().iconst(types::I64, (raw_val >> 64) as u64 as i64);
+ fx.bcx.ins().iconcat(lsb, msb)
}
- Some(GlobalAlloc::Function(instance)) => {
- let func_id =
- crate::abi::import_function(fx.tcx, fx.cx.module, instance);
- let local_func_id =
- fx.cx.module.declare_func_in_func(func_id, &mut fx.bcx.func);
- fx.bcx.ins().func_addr(fx.pointer_type, local_func_id)
- }
- Some(GlobalAlloc::Static(def_id)) => {
- assert!(fx.tcx.is_static(def_id));
- let data_id = data_id_for_static(fx.tcx, fx.cx.module, def_id, false);
- let local_data_id =
- fx.cx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
- if fx.clif_comments.enabled() {
- fx.add_comment(local_data_id, format!("{:?}", def_id));
- }
- fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
- }
- None => bug!("missing allocation {:?}", ptr.alloc_id),
- };
- let val = if ptr.offset.bytes() != 0 {
- fx.bcx.ins().iadd_imm(base_addr, i64::try_from(ptr.offset.bytes()).unwrap())
- } else {
- base_addr
+ _ => unreachable!(),
};
- CValue::by_val(val, layout)
+
+ let place = CPlace::new_stack_slot(fx, layout);
+ place.to_ptr().store(fx, val, MemFlags::trusted());
+ place.to_cvalue(fx)
}
}
- }
+ Scalar::Ptr(ptr, _size) => {
+ let (alloc_id, offset) = ptr.into_parts(); // we know the `offset` is relative
+ let alloc_kind = fx.tcx.get_global_alloc(alloc_id);
+ let base_addr = match alloc_kind {
+ Some(GlobalAlloc::Memory(alloc)) => {
+ let data_id = data_id_for_alloc_id(
+ &mut fx.constants_cx,
+ fx.module,
+ alloc_id,
+ alloc.inner().mutability,
+ );
+ let local_data_id =
+ fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ if fx.clif_comments.enabled() {
+ fx.add_comment(local_data_id, format!("{:?}", alloc_id));
+ }
+ fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ }
+ Some(GlobalAlloc::Function(instance)) => {
+ let func_id = crate::abi::import_function(fx.tcx, fx.module, instance);
+ let local_func_id =
+ fx.module.declare_func_in_func(func_id, &mut fx.bcx.func);
+ fx.bcx.ins().func_addr(fx.pointer_type, local_func_id)
+ }
+ Some(GlobalAlloc::Static(def_id)) => {
+ assert!(fx.tcx.is_static(def_id));
+ let data_id = data_id_for_static(fx.tcx, fx.module, def_id, false);
+ let local_data_id =
+ fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ if fx.clif_comments.enabled() {
+ fx.add_comment(local_data_id, format!("{:?}", def_id));
+ }
+ fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ }
+ None => bug!("missing allocation {:?}", alloc_id),
+ };
+ let val = if offset.bytes() != 0 {
+ fx.bcx.ins().iadd_imm(base_addr, i64::try_from(offset.bytes()).unwrap())
+ } else {
+ base_addr
+ };
+ CValue::by_val(val, layout)
+ }
+ },
ConstValue::ByRef { alloc, offset } => CValue::by_ref(
pointer_for_allocation(fx, alloc)
.offset_i64(fx, i64::try_from(offset.bytes()).unwrap()),
fn pointer_for_allocation<'tcx>(
fx: &mut FunctionCx<'_, '_, 'tcx>,
- alloc: &'tcx Allocation,
+ alloc: ConstAllocation<'tcx>,
) -> crate::pointer::Pointer {
let alloc_id = fx.tcx.create_memory_alloc(alloc);
- fx.constants_cx.todo.push(TodoItem::Alloc(alloc_id));
- let data_id =
- data_id_for_alloc_id(&mut fx.constants_cx, &mut *fx.cx.module, alloc_id, alloc.mutability);
+ let data_id = data_id_for_alloc_id(
+ &mut fx.constants_cx,
+ &mut *fx.module,
+ alloc_id,
+ alloc.inner().mutability,
+ );
- let local_data_id = fx.cx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ let local_data_id = fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
if fx.clif_comments.enabled() {
fx.add_comment(local_data_id, format!("{:?}", alloc_id));
}
crate::pointer::Pointer::new(global_ptr)
}
-fn data_id_for_alloc_id(
+pub(crate) fn data_id_for_alloc_id(
cx: &mut ConstantCx,
module: &mut dyn Module,
alloc_id: AllocId,
mutability: rustc_hir::Mutability,
) -> DataId {
+ cx.todo.push(TodoItem::Alloc(alloc_id));
*cx.anon_allocs.entry(alloc_id).or_insert_with(|| {
module.declare_anonymous_data(mutability == rustc_hir::Mutability::Mut, false).unwrap()
})
GlobalAlloc::Memory(alloc) => alloc,
GlobalAlloc::Function(_) | GlobalAlloc::Static(_) => unreachable!(),
};
- let data_id = data_id_for_alloc_id(cx, module, alloc_id, alloc.mutability);
+ let data_id = *cx.anon_allocs.entry(alloc_id).or_insert_with(|| {
+ module
+ .declare_anonymous_data(
+ alloc.inner().mutability == rustc_hir::Mutability::Mut,
+ false,
+ )
+ .unwrap()
+ });
(data_id, alloc, None)
}
TodoItem::Static(def_id) => {
//println!("static {:?}", def_id);
- let section_name = tcx.codegen_fn_attrs(def_id).link_section.map(|s| s.as_str());
+ let section_name = tcx.codegen_fn_attrs(def_id).link_section;
let alloc = tcx.eval_static_initializer(def_id).unwrap();
}
let mut data_ctx = DataContext::new();
+ let alloc = alloc.inner();
data_ctx.set_align(alloc.align.bytes());
if let Some(section_name) = section_name {
- // FIXME set correct segment for Mach-O files
- data_ctx.set_segment_section("", &*section_name);
+ let (segment_name, section_name) = if tcx.sess.target.is_like_osx {
+ let section_name = section_name.as_str();
+ if let Some(names) = section_name.split_once(',') {
+ names
+ } else {
+ tcx.sess.fatal(&format!(
+ "#[link_section = \"{}\"] is not valid for macos target: must be segment and section separated by comma",
+ section_name
+ ));
+ }
+ } else {
+ ("", section_name.as_str())
+ };
+ data_ctx.set_segment_section(segment_name, section_name);
}
let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len()).to_vec();
data_ctx.define(bytes.into_boxed_slice());
- for &(offset, (_tag, reloc)) in alloc.relocations().iter() {
+ for &(offset, alloc_id) in alloc.relocations().iter() {
let addend = {
let endianness = tcx.data_layout.endian;
let offset = offset.bytes() as usize;
read_target_uint(endianness, bytes).unwrap()
};
- let reloc_target_alloc = tcx.get_global_alloc(reloc).unwrap();
+ let reloc_target_alloc = tcx.get_global_alloc(alloc_id).unwrap();
let data_id = match reloc_target_alloc {
GlobalAlloc::Function(instance) => {
assert_eq!(addend, 0);
continue;
}
GlobalAlloc::Memory(target_alloc) => {
- cx.todo.push(TodoItem::Alloc(reloc));
- data_id_for_alloc_id(cx, module, reloc, target_alloc.mutability)
+ data_id_for_alloc_id(cx, module, alloc_id, target_alloc.inner().mutability)
}
GlobalAlloc::Static(def_id) => {
if tcx.codegen_fn_attrs(def_id).flags.contains(CodegenFnAttrFlags::THREAD_LOCAL)
operand: &Operand<'tcx>,
) -> Option<ConstValue<'tcx>> {
match operand {
- Operand::Copy(_) | Operand::Move(_) => None,
Operand::Constant(const_) => match const_.literal {
ConstantKind::Ty(const_) => {
- fx.monomorphize(const_).eval(fx.tcx, ParamEnv::reveal_all()).val.try_to_value()
+ fx.monomorphize(const_).eval(fx.tcx, ParamEnv::reveal_all()).val().try_to_value()
}
ConstantKind::Val(val, _) => Some(val),
},
+ // FIXME(rust-lang/rust#85105): Casts like `IMM8 as u32` result in the const being stored
+ // inside a temporary before being passed to the intrinsic requiring the const argument.
+ // This code tries to find a single constant defining definition of the referenced local.
+ Operand::Copy(place) | Operand::Move(place) => {
+ if !place.projection.is_empty() {
+ return None;
+ }
+ let mut computed_const_val = None;
+ for bb_data in fx.mir.basic_blocks() {
+ for stmt in &bb_data.statements {
+ match &stmt.kind {
+ StatementKind::Assign(local_and_rvalue) if &local_and_rvalue.0 == place => {
+ match &local_and_rvalue.1 {
+ Rvalue::Cast(CastKind::Misc, operand, ty) => {
+ if computed_const_val.is_some() {
+ return None; // local assigned twice
+ }
+ if !matches!(ty.kind(), ty::Uint(_) | ty::Int(_)) {
+ return None;
+ }
+ let const_val = mir_operand_get_const_val(fx, operand)?;
+ if fx.layout_of(*ty).size
+ != const_val.try_to_scalar_int()?.size()
+ {
+ return None;
+ }
+ computed_const_val = Some(const_val);
+ }
+ Rvalue::Use(operand) => {
+ computed_const_val = mir_operand_get_const_val(fx, operand)
+ }
+ _ => return None,
+ }
+ }
+ StatementKind::SetDiscriminant { place: stmt_place, variant_index: _ }
+ if &**stmt_place == place =>
+ {
+ return None;
+ }
+ StatementKind::CopyNonOverlapping(_) => {
+ return None;
+ } // conservative handling
+ StatementKind::Assign(_)
+ | StatementKind::FakeRead(_)
+ | StatementKind::SetDiscriminant { .. }
+ | StatementKind::Deinit(_)
+ | StatementKind::StorageLive(_)
+ | StatementKind::StorageDead(_)
+ | StatementKind::Retag(_, _)
+ | StatementKind::AscribeUserType(_, _)
+ | StatementKind::Coverage(_)
+ | StatementKind::Nop => {}
+ }
+ }
+ match &bb_data.terminator().kind {
+ TerminatorKind::Goto { .. }
+ | TerminatorKind::SwitchInt { .. }
+ | TerminatorKind::Resume
+ | TerminatorKind::Abort
+ | TerminatorKind::Return
+ | TerminatorKind::Unreachable
+ | TerminatorKind::Drop { .. }
+ | TerminatorKind::Assert { .. } => {}
+ TerminatorKind::DropAndReplace { .. }
+ | TerminatorKind::Yield { .. }
+ | TerminatorKind::GeneratorDrop
+ | TerminatorKind::FalseEdge { .. }
+ | TerminatorKind::FalseUnwind { .. } => unreachable!(),
+ TerminatorKind::InlineAsm { .. } => return None,
+ TerminatorKind::Call { destination: Some((call_place, _)), .. }
+ if call_place == place =>
+ {
+ return None;
+ }
+ TerminatorKind::Call { .. } => {}
+ }
+ }
+ computed_const_val
+ }
}
}