mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-31 13:04:42 +00:00
624 lines
27 KiB
Rust
624 lines
27 KiB
Rust
//! Handling of `static`s, `const`s and promoted allocations
|
|
|
|
use std::cmp::Ordering;
|
|
|
|
use cranelift_module::*;
|
|
use rustc_data_structures::fx::FxHashSet;
|
|
use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
|
|
use rustc_middle::mir::interpret::{AllocId, GlobalAlloc, Scalar, read_target_uint};
|
|
use rustc_middle::ty::{ExistentialTraitRef, ScalarInt};
|
|
|
|
use crate::prelude::*;
|
|
|
|
pub(crate) struct ConstantCx {
|
|
todo: Vec<TodoItem>,
|
|
anon_allocs: FxHashMap<AllocId, DataId>,
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
|
|
enum TodoItem {
|
|
Alloc(AllocId),
|
|
Static(DefId),
|
|
}
|
|
|
|
impl ConstantCx {
|
|
pub(crate) fn new() -> Self {
|
|
ConstantCx { todo: vec![], anon_allocs: FxHashMap::default() }
|
|
}
|
|
|
|
pub(crate) fn finalize(mut self, tcx: TyCtxt<'_>, module: &mut dyn Module) {
|
|
define_all_allocs(tcx, module, &mut self);
|
|
}
|
|
}
|
|
|
|
pub(crate) fn codegen_static(tcx: TyCtxt<'_>, module: &mut dyn Module, def_id: DefId) -> DataId {
|
|
let mut constants_cx = ConstantCx::new();
|
|
constants_cx.todo.push(TodoItem::Static(def_id));
|
|
constants_cx.finalize(tcx, module);
|
|
|
|
data_id_for_static(
|
|
tcx, module, def_id, false,
|
|
// For a declaration the stated mutability doesn't matter.
|
|
false,
|
|
)
|
|
}
|
|
|
|
pub(crate) fn codegen_tls_ref<'tcx>(
|
|
fx: &mut FunctionCx<'_, '_, 'tcx>,
|
|
def_id: DefId,
|
|
layout: TyAndLayout<'tcx>,
|
|
) -> CValue<'tcx> {
|
|
let tls_ptr = if !def_id.is_local() && fx.tcx.needs_thread_local_shim(def_id) {
|
|
let instance = ty::Instance {
|
|
def: ty::InstanceKind::ThreadLocalShim(def_id),
|
|
args: ty::GenericArgs::empty(),
|
|
};
|
|
let func_ref = fx.get_function_ref(instance);
|
|
let call = fx.bcx.ins().call(func_ref, &[]);
|
|
fx.bcx.func.dfg.first_result(call)
|
|
} else {
|
|
let data_id = data_id_for_static(
|
|
fx.tcx, fx.module, def_id, false,
|
|
// For a declaration the stated mutability doesn't matter.
|
|
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));
|
|
}
|
|
fx.bcx.ins().tls_value(fx.pointer_type, local_data_id)
|
|
};
|
|
CValue::by_val(tls_ptr, layout)
|
|
}
|
|
|
|
pub(crate) fn eval_mir_constant<'tcx>(
|
|
fx: &FunctionCx<'_, '_, 'tcx>,
|
|
constant: &ConstOperand<'tcx>,
|
|
) -> (ConstValue<'tcx>, Ty<'tcx>) {
|
|
let cv = fx.monomorphize(constant.const_);
|
|
// This cannot fail because we checked all required_consts in advance.
|
|
let val = cv
|
|
.eval(fx.tcx, ty::TypingEnv::fully_monomorphized(), constant.span)
|
|
.expect("erroneous constant missed by mono item collection");
|
|
(val, cv.ty())
|
|
}
|
|
|
|
pub(crate) fn codegen_constant_operand<'tcx>(
|
|
fx: &mut FunctionCx<'_, '_, 'tcx>,
|
|
constant: &ConstOperand<'tcx>,
|
|
) -> CValue<'tcx> {
|
|
let (const_val, ty) = eval_mir_constant(fx, constant);
|
|
codegen_const_value(fx, const_val, ty)
|
|
}
|
|
|
|
pub(crate) fn codegen_const_value<'tcx>(
|
|
fx: &mut FunctionCx<'_, '_, 'tcx>,
|
|
const_val: ConstValue<'tcx>,
|
|
ty: Ty<'tcx>,
|
|
) -> CValue<'tcx> {
|
|
let layout = fx.layout_of(ty);
|
|
assert!(layout.is_sized(), "unsized const value");
|
|
|
|
if layout.is_zst() {
|
|
return CValue::zst(layout);
|
|
}
|
|
|
|
match const_val {
|
|
ConstValue::ZeroSized => unreachable!(), // we already handled ZST above
|
|
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.size().truncate(int.to_bits(int.size()));
|
|
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)
|
|
}
|
|
_ => unreachable!(),
|
|
};
|
|
|
|
// FIXME avoid this extra copy to the stack and directly write to the final
|
|
// destination
|
|
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 (prov, offset) = ptr.into_parts(); // we know the `offset` is relative
|
|
let alloc_id = prov.alloc_id();
|
|
let base_addr = match fx.tcx.global_alloc(alloc_id) {
|
|
GlobalAlloc::Memory(alloc) => {
|
|
if alloc.inner().len() == 0 {
|
|
assert_eq!(offset, Size::ZERO);
|
|
fx.bcx.ins().iconst(fx.pointer_type, alloc.inner().align.bytes() as i64)
|
|
} else {
|
|
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)
|
|
}
|
|
}
|
|
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)
|
|
}
|
|
GlobalAlloc::VTable(ty, dyn_ty) => {
|
|
let data_id = data_id_for_vtable(
|
|
fx.tcx,
|
|
&mut fx.constants_cx,
|
|
fx.module,
|
|
ty,
|
|
dyn_ty.principal().map(|principal| {
|
|
fx.tcx.instantiate_bound_regions_with_erased(principal)
|
|
}),
|
|
);
|
|
let local_data_id =
|
|
fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
|
|
fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
|
|
}
|
|
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,
|
|
// For a declaration the stated mutability doesn't matter.
|
|
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)
|
|
}
|
|
};
|
|
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::Indirect { alloc_id, offset } => CValue::by_ref(
|
|
pointer_for_allocation(fx, alloc_id)
|
|
.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);
|
|
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)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn pointer_for_allocation<'tcx>(
|
|
fx: &mut FunctionCx<'_, '_, 'tcx>,
|
|
alloc_id: AllocId,
|
|
) -> crate::pointer::Pointer {
|
|
let alloc = fx.tcx.global_alloc(alloc_id).unwrap_memory();
|
|
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));
|
|
}
|
|
let global_ptr = fx.bcx.ins().global_value(fx.pointer_type, local_data_id);
|
|
crate::pointer::Pointer::new(global_ptr)
|
|
}
|
|
|
|
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.is_mut(), false).unwrap())
|
|
}
|
|
|
|
pub(crate) fn data_id_for_vtable<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
cx: &mut ConstantCx,
|
|
module: &mut dyn Module,
|
|
ty: Ty<'tcx>,
|
|
trait_ref: Option<ExistentialTraitRef<'tcx>>,
|
|
) -> DataId {
|
|
let alloc_id = tcx.vtable_allocation((ty, trait_ref));
|
|
data_id_for_alloc_id(cx, module, alloc_id, Mutability::Not)
|
|
}
|
|
|
|
fn data_id_for_static(
|
|
tcx: TyCtxt<'_>,
|
|
module: &mut dyn Module,
|
|
def_id: DefId,
|
|
definition: bool,
|
|
definition_writable: bool,
|
|
) -> DataId {
|
|
let attrs = tcx.codegen_fn_attrs(def_id);
|
|
|
|
let instance = Instance::mono(tcx, def_id);
|
|
let symbol_name = tcx.symbol_name(instance).name;
|
|
|
|
if let Some(import_linkage) = attrs.import_linkage {
|
|
assert!(!definition);
|
|
assert!(!tcx.is_mutable_static(def_id));
|
|
|
|
let ty = instance.ty(tcx, ty::TypingEnv::fully_monomorphized());
|
|
let align = tcx
|
|
.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty))
|
|
.unwrap()
|
|
.align
|
|
.abi
|
|
.bytes();
|
|
|
|
let linkage = if import_linkage == rustc_middle::mir::mono::Linkage::ExternalWeak
|
|
|| import_linkage == rustc_middle::mir::mono::Linkage::WeakAny
|
|
{
|
|
Linkage::Preemptible
|
|
} else {
|
|
Linkage::Import
|
|
};
|
|
|
|
let data_id = match module.declare_data(
|
|
symbol_name,
|
|
linkage,
|
|
false,
|
|
attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL),
|
|
) {
|
|
Ok(data_id) => data_id,
|
|
Err(ModuleError::IncompatibleDeclaration(_)) => tcx.dcx().fatal(format!(
|
|
"attempt to declare `{symbol_name}` as static, but it was already declared as function"
|
|
)),
|
|
Err(err) => Err::<_, _>(err).unwrap(),
|
|
};
|
|
|
|
// Comment copied from https://github.com/rust-lang/rust/blob/45060c2a66dfd667f88bd8b94261b28a58d85bd5/src/librustc_codegen_llvm/consts.rs#L141
|
|
// Declare an internal global `extern_with_linkage_foo` which
|
|
// is initialized with the address of `foo`. If `foo` is
|
|
// discarded during linking (for example, if `foo` has weak
|
|
// linkage and there are no definitions), then
|
|
// `extern_with_linkage_foo` will instead be initialized to
|
|
// zero.
|
|
|
|
let ref_name = format!("_rust_extern_with_linkage_{}", symbol_name);
|
|
let ref_data_id = module.declare_data(&ref_name, Linkage::Local, false, false).unwrap();
|
|
let mut data = DataDescription::new();
|
|
data.set_align(align);
|
|
let data_gv = module.declare_data_in_data(data_id, &mut data);
|
|
data.define(std::iter::repeat(0).take(pointer_ty(tcx).bytes() as usize).collect());
|
|
data.write_data_addr(0, data_gv, 0);
|
|
match module.define_data(ref_data_id, &data) {
|
|
// Every time the static is referenced there will be another definition of this global,
|
|
// so duplicate definitions are expected and allowed.
|
|
Err(ModuleError::DuplicateDefinition(_)) => {}
|
|
res => res.unwrap(),
|
|
}
|
|
|
|
return ref_data_id;
|
|
}
|
|
|
|
let linkage = if definition {
|
|
crate::linkage::get_static_linkage(tcx, def_id)
|
|
} else if attrs.linkage == Some(rustc_middle::mir::mono::Linkage::ExternalWeak)
|
|
|| attrs.linkage == Some(rustc_middle::mir::mono::Linkage::WeakAny)
|
|
{
|
|
Linkage::Preemptible
|
|
} else {
|
|
Linkage::Import
|
|
};
|
|
|
|
let data_id = match module.declare_data(
|
|
symbol_name,
|
|
linkage,
|
|
definition_writable,
|
|
attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL),
|
|
) {
|
|
Ok(data_id) => data_id,
|
|
Err(ModuleError::IncompatibleDeclaration(_)) => tcx.dcx().fatal(format!(
|
|
"attempt to declare `{symbol_name}` as static, but it was already declared as function"
|
|
)),
|
|
Err(err) => Err::<_, _>(err).unwrap(),
|
|
};
|
|
|
|
data_id
|
|
}
|
|
|
|
fn define_all_allocs(tcx: TyCtxt<'_>, module: &mut dyn Module, cx: &mut ConstantCx) {
|
|
let mut done = FxHashSet::default();
|
|
while let Some(todo_item) = cx.todo.pop() {
|
|
if !done.insert(todo_item) {
|
|
continue;
|
|
}
|
|
|
|
let (data_id, alloc, section_name) = match todo_item {
|
|
TodoItem::Alloc(alloc_id) => {
|
|
let alloc = match tcx.global_alloc(alloc_id) {
|
|
GlobalAlloc::Memory(alloc) => alloc,
|
|
GlobalAlloc::Function { .. }
|
|
| GlobalAlloc::Static(_)
|
|
| GlobalAlloc::VTable(..) => {
|
|
unreachable!()
|
|
}
|
|
};
|
|
// FIXME: should we have a cache so we don't do this multiple times for the same `ConstAllocation`?
|
|
let data_id = *cx.anon_allocs.entry(alloc_id).or_insert_with(|| {
|
|
module.declare_anonymous_data(alloc.inner().mutability.is_mut(), false).unwrap()
|
|
});
|
|
(data_id, alloc, None)
|
|
}
|
|
TodoItem::Static(def_id) => {
|
|
let section_name = tcx.codegen_fn_attrs(def_id).link_section;
|
|
|
|
let alloc = tcx.eval_static_initializer(def_id).unwrap();
|
|
|
|
let data_id = data_id_for_static(
|
|
tcx,
|
|
module,
|
|
def_id,
|
|
true,
|
|
alloc.inner().mutability == Mutability::Mut,
|
|
);
|
|
(data_id, alloc, section_name)
|
|
}
|
|
};
|
|
|
|
let mut data = DataDescription::new();
|
|
let alloc = alloc.inner();
|
|
data.set_align(alloc.align.bytes());
|
|
|
|
if let Some(section_name) = section_name {
|
|
let (segment_name, section_name) = if tcx.sess.target.is_like_darwin {
|
|
// See https://github.com/llvm/llvm-project/blob/main/llvm/lib/MC/MCSectionMachO.cpp
|
|
let mut parts = section_name.as_str().split(',');
|
|
let Some(segment_name) = parts.next() else {
|
|
tcx.dcx().fatal(format!(
|
|
"#[link_section = \"{}\"] is not valid for macos target: must be segment and section separated by comma",
|
|
section_name
|
|
));
|
|
};
|
|
let Some(section_name) = parts.next() else {
|
|
tcx.dcx().fatal(format!(
|
|
"#[link_section = \"{}\"] is not valid for macos target: must be segment and section separated by comma",
|
|
section_name
|
|
));
|
|
};
|
|
if section_name.len() > 16 {
|
|
tcx.dcx().fatal(format!(
|
|
"#[link_section = \"{}\"] is not valid for macos target: section name bigger than 16 bytes",
|
|
section_name
|
|
));
|
|
}
|
|
let section_type = parts.next().unwrap_or("regular");
|
|
if section_type != "regular" && section_type != "cstring_literals" {
|
|
tcx.dcx().fatal(format!(
|
|
"#[link_section = \"{}\"] is not supported: unsupported section type {}",
|
|
section_name, section_type,
|
|
));
|
|
}
|
|
let _attrs = parts.next();
|
|
if parts.next().is_some() {
|
|
tcx.dcx().fatal(format!(
|
|
"#[link_section = \"{}\"] is not valid for macos target: too many components",
|
|
section_name
|
|
));
|
|
}
|
|
// FIXME(bytecodealliance/wasmtime#8901) set S_CSTRING_LITERALS section type when
|
|
// cstring_literals is specified
|
|
(segment_name, section_name)
|
|
} else {
|
|
("", section_name.as_str())
|
|
};
|
|
data.set_segment_section(segment_name, section_name);
|
|
}
|
|
|
|
let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len()).to_vec();
|
|
data.define(bytes.into_boxed_slice());
|
|
|
|
for &(offset, prov) in alloc.provenance().ptrs().iter() {
|
|
let alloc_id = prov.alloc_id();
|
|
let addend = {
|
|
let endianness = tcx.data_layout.endian;
|
|
let offset = offset.bytes() as usize;
|
|
let ptr_size = tcx.data_layout.pointer_size;
|
|
let bytes = &alloc.inspect_with_uninit_and_ptr_outside_interpreter(
|
|
offset..offset + ptr_size.bytes() as usize,
|
|
);
|
|
read_target_uint(endianness, bytes).unwrap()
|
|
};
|
|
|
|
let reloc_target_alloc = tcx.global_alloc(alloc_id);
|
|
let data_id = match reloc_target_alloc {
|
|
GlobalAlloc::Function { instance, .. } => {
|
|
assert_eq!(addend, 0);
|
|
let func_id = crate::abi::import_function(tcx, module, instance);
|
|
let local_func_id = module.declare_func_in_data(func_id, &mut data);
|
|
data.write_function_addr(offset.bytes() as u32, local_func_id);
|
|
continue;
|
|
}
|
|
GlobalAlloc::Memory(target_alloc) => {
|
|
data_id_for_alloc_id(cx, module, alloc_id, target_alloc.inner().mutability)
|
|
}
|
|
GlobalAlloc::VTable(ty, dyn_ty) => data_id_for_vtable(
|
|
tcx,
|
|
cx,
|
|
module,
|
|
ty,
|
|
dyn_ty
|
|
.principal()
|
|
.map(|principal| tcx.instantiate_bound_regions_with_erased(principal)),
|
|
),
|
|
GlobalAlloc::Static(def_id) => {
|
|
if tcx.codegen_fn_attrs(def_id).flags.contains(CodegenFnAttrFlags::THREAD_LOCAL)
|
|
{
|
|
tcx.dcx().fatal(format!(
|
|
"Allocation {:?} contains reference to TLS value {:?}",
|
|
alloc_id, def_id
|
|
));
|
|
}
|
|
|
|
// Don't push a `TodoItem::Static` here, as it will cause statics used by
|
|
// multiple crates to be duplicated between them. It isn't necessary anyway,
|
|
// as it will get pushed by `codegen_static` when necessary.
|
|
data_id_for_static(
|
|
tcx, module, def_id, false,
|
|
// For a declaration the stated mutability doesn't matter.
|
|
false,
|
|
)
|
|
}
|
|
};
|
|
|
|
let global_value = module.declare_data_in_data(data_id, &mut data);
|
|
data.write_data_addr(offset.bytes() as u32, global_value, addend as i64);
|
|
}
|
|
|
|
module.define_data(data_id, &data).unwrap();
|
|
}
|
|
|
|
assert!(cx.todo.is_empty(), "{:?}", cx.todo);
|
|
}
|
|
|
|
/// Used only for intrinsic implementations that need a compile-time constant
|
|
///
|
|
/// All uses of this function are a bug inside stdarch. [`eval_mir_constant`]
|
|
/// should be used everywhere, but for some vendor intrinsics stdarch forgets
|
|
/// to wrap the immediate argument in `const {}`, necesitating this hack to get
|
|
/// the correct value at compile time instead.
|
|
pub(crate) fn mir_operand_get_const_val<'tcx>(
|
|
fx: &FunctionCx<'_, '_, 'tcx>,
|
|
operand: &Operand<'tcx>,
|
|
) -> Option<ScalarInt> {
|
|
match operand {
|
|
Operand::Constant(const_) => eval_mir_constant(fx, const_).0.try_to_scalar_int(),
|
|
// 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_scalar_int = None;
|
|
for bb_data in fx.mir.basic_blocks.iter() {
|
|
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::IntToInt
|
|
| CastKind::FloatToFloat
|
|
| CastKind::FloatToInt
|
|
| CastKind::IntToFloat
|
|
| CastKind::FnPtrToPtr
|
|
| CastKind::PtrToPtr,
|
|
operand,
|
|
ty,
|
|
) => {
|
|
if computed_scalar_int.is_some() {
|
|
return None; // local assigned twice
|
|
}
|
|
if !matches!(ty.kind(), ty::Uint(_) | ty::Int(_)) {
|
|
return None;
|
|
}
|
|
let scalar_int = mir_operand_get_const_val(fx, operand)?;
|
|
let scalar_int =
|
|
match fx.layout_of(*ty).size.cmp(&scalar_int.size()) {
|
|
Ordering::Equal => scalar_int,
|
|
Ordering::Less => match ty.kind() {
|
|
ty::Uint(_) => ScalarInt::try_from_uint(
|
|
scalar_int.to_uint(scalar_int.size()),
|
|
fx.layout_of(*ty).size,
|
|
)
|
|
.unwrap(),
|
|
ty::Int(_) => ScalarInt::try_from_int(
|
|
scalar_int.to_int(scalar_int.size()),
|
|
fx.layout_of(*ty).size,
|
|
)
|
|
.unwrap(),
|
|
_ => unreachable!(),
|
|
},
|
|
Ordering::Greater => return None,
|
|
};
|
|
computed_scalar_int = Some(scalar_int);
|
|
}
|
|
Rvalue::Use(operand) => {
|
|
computed_scalar_int = mir_operand_get_const_val(fx, operand)
|
|
}
|
|
_ => return None,
|
|
}
|
|
}
|
|
StatementKind::SetDiscriminant { place: stmt_place, variant_index: _ }
|
|
if &**stmt_place == place =>
|
|
{
|
|
return None;
|
|
}
|
|
StatementKind::Intrinsic(ref intrinsic) => match **intrinsic {
|
|
NonDivergingIntrinsic::CopyNonOverlapping(..) => return None,
|
|
NonDivergingIntrinsic::Assume(..) => {}
|
|
},
|
|
// conservative handling
|
|
StatementKind::Assign(_)
|
|
| StatementKind::FakeRead(_)
|
|
| StatementKind::SetDiscriminant { .. }
|
|
| StatementKind::Deinit(_)
|
|
| StatementKind::StorageLive(_)
|
|
| StatementKind::StorageDead(_)
|
|
| StatementKind::Retag(_, _)
|
|
| StatementKind::AscribeUserType(_, _)
|
|
| StatementKind::PlaceMention(..)
|
|
| StatementKind::Coverage(_)
|
|
| StatementKind::ConstEvalCounter
|
|
| StatementKind::BackwardIncompatibleDropHint { .. }
|
|
| StatementKind::Nop => {}
|
|
}
|
|
}
|
|
match &bb_data.terminator().kind {
|
|
TerminatorKind::Goto { .. }
|
|
| TerminatorKind::SwitchInt { .. }
|
|
| TerminatorKind::UnwindResume
|
|
| TerminatorKind::UnwindTerminate(_)
|
|
| TerminatorKind::Return
|
|
| TerminatorKind::Unreachable
|
|
| TerminatorKind::Drop { .. }
|
|
| TerminatorKind::Assert { .. } => {}
|
|
TerminatorKind::Yield { .. }
|
|
| TerminatorKind::CoroutineDrop
|
|
| TerminatorKind::FalseEdge { .. }
|
|
| TerminatorKind::FalseUnwind { .. } => unreachable!(),
|
|
TerminatorKind::InlineAsm { .. } => return None,
|
|
TerminatorKind::Call { destination, target: Some(_), .. }
|
|
if destination == place =>
|
|
{
|
|
return None;
|
|
}
|
|
TerminatorKind::TailCall { .. } => return None,
|
|
TerminatorKind::Call { .. } => {}
|
|
}
|
|
}
|
|
computed_scalar_int
|
|
}
|
|
}
|
|
}
|