b30cf11b96
Currently, when declaring an extern weak function in Rust, we use the
following syntax:
```rust
unsafe extern "C" {
#[linkage = "extern_weak"]
static FOO: Option<unsafe extern "C" fn() -> ()>;
}
```
This allows runtime-checking the extern weak symbol through the Option.
When emitting LLVM-IR, the Rust compiler currently emits this static
as an i8, and a pointer that is initialized with the value of the global
i8 and represents the nullabilty e.g.
```
@FOO = extern_weak global i8
@_rust_extern_with_linkage_FOO = internal global ptr @FOO
```
This approach does not work well with CFI, where we need to attach CFI
metadata to a concrete function declaration, which was pointed out in
https://github.com/rust-lang/rust/issues/115199.
This change switches to emitting a proper function declaration instead
of a global i8. This allows CFI to work for extern_weak functions.
We keep initializing the Rust internal symbol with the function
declaration, which preserves the correct behavior for runtime checking
the Option.
Co-authored-by: Jakob Koschel <jakobkoschel@google.com>
583 lines
25 KiB
Rust
583 lines
25 KiB
Rust
use std::ops::Range;
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use rustc_abi::{
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Align, AlignFromBytesError, HasDataLayout, Primitive, Scalar, Size, WrappingRange,
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};
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use rustc_codegen_ssa::common;
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use rustc_codegen_ssa::traits::*;
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use rustc_hir::LangItem;
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use rustc_hir::def::DefKind;
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use rustc_hir::def_id::DefId;
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use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
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use rustc_middle::mir::interpret::{
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Allocation, ConstAllocation, ErrorHandled, InitChunk, Pointer, Scalar as InterpScalar,
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read_target_uint,
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};
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use rustc_middle::mir::mono::{Linkage, MonoItem};
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use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
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use rustc_middle::ty::{self, Instance};
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use rustc_middle::{bug, span_bug};
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use tracing::{debug, instrument, trace};
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use crate::common::{AsCCharPtr, CodegenCx};
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use crate::errors::{
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InvalidMinimumAlignmentNotPowerOfTwo, InvalidMinimumAlignmentTooLarge, SymbolAlreadyDefined,
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};
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use crate::llvm::{self, True};
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use crate::type_::Type;
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use crate::type_of::LayoutLlvmExt;
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use crate::value::Value;
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use crate::{base, debuginfo};
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pub(crate) fn const_alloc_to_llvm<'ll>(
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cx: &CodegenCx<'ll, '_>,
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alloc: ConstAllocation<'_>,
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is_static: bool,
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) -> &'ll Value {
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let alloc = alloc.inner();
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// We expect that callers of const_alloc_to_llvm will instead directly codegen a pointer or
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// integer for any &ZST where the ZST is a constant (i.e. not a static). We should never be
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// producing empty LLVM allocations as they're just adding noise to binaries and forcing less
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// optimal codegen.
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//
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// Statics have a guaranteed meaningful address so it's less clear that we want to do
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// something like this; it's also harder.
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if !is_static {
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assert!(alloc.len() != 0);
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}
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let mut llvals = Vec::with_capacity(alloc.provenance().ptrs().len() + 1);
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let dl = cx.data_layout();
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let pointer_size = dl.pointer_size.bytes() as usize;
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// Note: this function may call `inspect_with_uninit_and_ptr_outside_interpreter`, so `range`
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// must be within the bounds of `alloc` and not contain or overlap a pointer provenance.
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fn append_chunks_of_init_and_uninit_bytes<'ll, 'a, 'b>(
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llvals: &mut Vec<&'ll Value>,
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cx: &'a CodegenCx<'ll, 'b>,
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alloc: &'a Allocation,
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range: Range<usize>,
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) {
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let chunks = alloc.init_mask().range_as_init_chunks(range.clone().into());
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let chunk_to_llval = move |chunk| match chunk {
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InitChunk::Init(range) => {
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let range = (range.start.bytes() as usize)..(range.end.bytes() as usize);
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let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(range);
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cx.const_bytes(bytes)
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}
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InitChunk::Uninit(range) => {
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let len = range.end.bytes() - range.start.bytes();
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cx.const_undef(cx.type_array(cx.type_i8(), len))
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}
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};
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// Generating partially-uninit consts is limited to small numbers of chunks,
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// to avoid the cost of generating large complex const expressions.
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// For example, `[(u32, u8); 1024 * 1024]` contains uninit padding in each element, and
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// would result in `{ [5 x i8] zeroinitializer, [3 x i8] undef, ...repeat 1M times... }`.
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let max = cx.sess().opts.unstable_opts.uninit_const_chunk_threshold;
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let allow_uninit_chunks = chunks.clone().take(max.saturating_add(1)).count() <= max;
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if allow_uninit_chunks {
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llvals.extend(chunks.map(chunk_to_llval));
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} else {
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// If this allocation contains any uninit bytes, codegen as if it was initialized
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// (using some arbitrary value for uninit bytes).
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let bytes = alloc.inspect_with_uninit_and_ptr_outside_interpreter(range);
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llvals.push(cx.const_bytes(bytes));
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}
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}
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let mut next_offset = 0;
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for &(offset, prov) in alloc.provenance().ptrs().iter() {
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let offset = offset.bytes();
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assert_eq!(offset as usize as u64, offset);
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let offset = offset as usize;
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if offset > next_offset {
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// This `inspect` is okay since we have checked that there is no provenance, it
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// is within the bounds of the allocation, and it doesn't affect interpreter execution
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// (we inspect the result after interpreter execution).
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append_chunks_of_init_and_uninit_bytes(&mut llvals, cx, alloc, next_offset..offset);
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}
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let ptr_offset = read_target_uint(
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dl.endian,
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// This `inspect` is okay since it is within the bounds of the allocation, it doesn't
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// affect interpreter execution (we inspect the result after interpreter execution),
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// and we properly interpret the provenance as a relocation pointer offset.
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alloc.inspect_with_uninit_and_ptr_outside_interpreter(offset..(offset + pointer_size)),
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)
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.expect("const_alloc_to_llvm: could not read relocation pointer")
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as u64;
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let address_space = cx.tcx.global_alloc(prov.alloc_id()).address_space(cx);
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llvals.push(cx.scalar_to_backend(
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InterpScalar::from_pointer(Pointer::new(prov, Size::from_bytes(ptr_offset)), &cx.tcx),
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Scalar::Initialized {
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value: Primitive::Pointer(address_space),
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valid_range: WrappingRange::full(dl.pointer_size),
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},
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cx.type_ptr_ext(address_space),
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));
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next_offset = offset + pointer_size;
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}
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if alloc.len() >= next_offset {
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let range = next_offset..alloc.len();
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// This `inspect` is okay since we have check that it is after all provenance, it is
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// within the bounds of the allocation, and it doesn't affect interpreter execution (we
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// inspect the result after interpreter execution).
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append_chunks_of_init_and_uninit_bytes(&mut llvals, cx, alloc, range);
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}
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cx.const_struct(&llvals, true)
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}
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fn codegen_static_initializer<'ll, 'tcx>(
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cx: &CodegenCx<'ll, 'tcx>,
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def_id: DefId,
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) -> Result<(&'ll Value, ConstAllocation<'tcx>), ErrorHandled> {
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let alloc = cx.tcx.eval_static_initializer(def_id)?;
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Ok((const_alloc_to_llvm(cx, alloc, /*static*/ true), alloc))
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}
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fn set_global_alignment<'ll>(cx: &CodegenCx<'ll, '_>, gv: &'ll Value, mut align: Align) {
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// The target may require greater alignment for globals than the type does.
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// Note: GCC and Clang also allow `__attribute__((aligned))` on variables,
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// which can force it to be smaller. Rust doesn't support this yet.
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if let Some(min) = cx.sess().target.min_global_align {
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match Align::from_bits(min) {
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Ok(min) => align = align.max(min),
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Err(err) => match err {
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AlignFromBytesError::NotPowerOfTwo(align) => {
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cx.sess().dcx().emit_err(InvalidMinimumAlignmentNotPowerOfTwo { align });
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}
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AlignFromBytesError::TooLarge(align) => {
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cx.sess().dcx().emit_err(InvalidMinimumAlignmentTooLarge { align });
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}
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},
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}
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}
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unsafe {
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llvm::LLVMSetAlignment(gv, align.bytes() as u32);
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}
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}
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fn check_and_apply_linkage<'ll, 'tcx>(
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cx: &CodegenCx<'ll, 'tcx>,
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attrs: &CodegenFnAttrs,
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llty: &'ll Type,
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sym: &str,
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def_id: DefId,
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) -> &'ll Value {
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if let Some(linkage) = attrs.import_linkage {
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debug!("get_static: sym={} linkage={:?}", sym, linkage);
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// Declare a symbol `foo`. If `foo` is an extern_weak symbol, we declare
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// an extern_weak function, otherwise a global with the desired linkage.
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let g1 = if matches!(attrs.import_linkage, Some(Linkage::ExternalWeak)) {
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// An `extern_weak` function is represented as an `Option<unsafe extern ...>`,
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// we extract the function signature and declare it as an extern_weak function
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// instead of an extern_weak i8.
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let instance = Instance::mono(cx.tcx, def_id);
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if let ty::Adt(struct_def, args) = instance.ty(cx.tcx, cx.typing_env()).kind()
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&& cx.tcx.is_lang_item(struct_def.did(), LangItem::Option)
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&& let ty::FnPtr(sig, header) = args.type_at(0).kind()
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{
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let fn_sig = sig.with(*header);
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let fn_abi = cx.fn_abi_of_fn_ptr(fn_sig, ty::List::empty());
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cx.declare_fn(sym, &fn_abi, None)
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} else {
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cx.declare_global(sym, cx.type_i8())
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}
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} else {
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cx.declare_global(sym, cx.type_i8())
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};
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llvm::set_linkage(g1, base::linkage_to_llvm(linkage));
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// Declare an internal global `extern_with_linkage_foo` which
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// is initialized with the address of `foo`. If `foo` is
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// discarded during linking (for example, if `foo` has weak
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// linkage and there are no definitions), then
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// `extern_with_linkage_foo` will instead be initialized to
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// zero.
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let mut real_name = "_rust_extern_with_linkage_".to_string();
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real_name.push_str(sym);
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let g2 = cx.define_global(&real_name, llty).unwrap_or_else(|| {
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cx.sess().dcx().emit_fatal(SymbolAlreadyDefined {
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span: cx.tcx.def_span(def_id),
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symbol_name: sym,
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})
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});
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llvm::set_linkage(g2, llvm::Linkage::InternalLinkage);
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llvm::set_initializer(g2, g1);
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g2
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} else if cx.tcx.sess.target.arch == "x86"
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&& common::is_mingw_gnu_toolchain(&cx.tcx.sess.target)
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&& let Some(dllimport) = crate::common::get_dllimport(cx.tcx, def_id, sym)
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{
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cx.declare_global(&common::i686_decorated_name(dllimport, true, true, false), llty)
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} else {
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// Generate an external declaration.
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// FIXME(nagisa): investigate whether it can be changed into define_global
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cx.declare_global(sym, llty)
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}
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}
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impl<'ll> CodegenCx<'ll, '_> {
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pub(crate) fn const_bitcast(&self, val: &'ll Value, ty: &'ll Type) -> &'ll Value {
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unsafe { llvm::LLVMConstBitCast(val, ty) }
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}
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pub(crate) fn const_pointercast(&self, val: &'ll Value, ty: &'ll Type) -> &'ll Value {
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unsafe { llvm::LLVMConstPointerCast(val, ty) }
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}
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/// Create a global variable.
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///
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/// The returned global variable is a pointer in the default address space for globals.
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/// Fails if a symbol with the given name already exists.
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pub(crate) fn static_addr_of_mut(
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&self,
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cv: &'ll Value,
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align: Align,
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kind: Option<&str>,
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) -> &'ll Value {
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let gv = match kind {
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Some(kind) if !self.tcx.sess.fewer_names() => {
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let name = self.generate_local_symbol_name(kind);
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let gv = self.define_global(&name, self.val_ty(cv)).unwrap_or_else(|| {
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bug!("symbol `{}` is already defined", name);
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});
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llvm::set_linkage(gv, llvm::Linkage::PrivateLinkage);
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gv
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}
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_ => self.define_private_global(self.val_ty(cv)),
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};
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llvm::set_initializer(gv, cv);
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set_global_alignment(self, gv, align);
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llvm::SetUnnamedAddress(gv, llvm::UnnamedAddr::Global);
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gv
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}
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/// Create a global constant.
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///
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/// The returned global variable is a pointer in the default address space for globals.
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pub(crate) fn static_addr_of_impl(
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&self,
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cv: &'ll Value,
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align: Align,
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kind: Option<&str>,
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) -> &'ll Value {
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if let Some(&gv) = self.const_globals.borrow().get(&cv) {
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unsafe {
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// Upgrade the alignment in cases where the same constant is used with different
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// alignment requirements
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let llalign = align.bytes() as u32;
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if llalign > llvm::LLVMGetAlignment(gv) {
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llvm::LLVMSetAlignment(gv, llalign);
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}
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}
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return gv;
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}
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let gv = self.static_addr_of_mut(cv, align, kind);
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unsafe {
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llvm::LLVMSetGlobalConstant(gv, True);
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}
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self.const_globals.borrow_mut().insert(cv, gv);
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gv
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}
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#[instrument(level = "debug", skip(self))]
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pub(crate) fn get_static(&self, def_id: DefId) -> &'ll Value {
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let instance = Instance::mono(self.tcx, def_id);
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trace!(?instance);
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let DefKind::Static { nested, .. } = self.tcx.def_kind(def_id) else { bug!() };
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// Nested statics do not have a type, so pick a dummy type and let `codegen_static` figure
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// out the llvm type from the actual evaluated initializer.
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let llty = if nested {
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self.type_i8()
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} else {
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let ty = instance.ty(self.tcx, self.typing_env());
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trace!(?ty);
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self.layout_of(ty).llvm_type(self)
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};
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self.get_static_inner(def_id, llty)
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}
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#[instrument(level = "debug", skip(self, llty))]
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fn get_static_inner(&self, def_id: DefId, llty: &'ll Type) -> &'ll Value {
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let instance = Instance::mono(self.tcx, def_id);
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if let Some(&g) = self.instances.borrow().get(&instance) {
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trace!("used cached value");
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return g;
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}
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let defined_in_current_codegen_unit =
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self.codegen_unit.items().contains_key(&MonoItem::Static(def_id));
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assert!(
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!defined_in_current_codegen_unit,
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"consts::get_static() should always hit the cache for \
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statics defined in the same CGU, but did not for `{def_id:?}`"
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);
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let sym = self.tcx.symbol_name(instance).name;
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let fn_attrs = self.tcx.codegen_fn_attrs(def_id);
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debug!(?sym, ?fn_attrs);
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let g = if def_id.is_local() && !self.tcx.is_foreign_item(def_id) {
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if let Some(g) = self.get_declared_value(sym) {
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if self.val_ty(g) != self.type_ptr() {
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span_bug!(self.tcx.def_span(def_id), "Conflicting types for static");
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}
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}
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let g = self.declare_global(sym, llty);
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if !self.tcx.is_reachable_non_generic(def_id) {
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llvm::set_visibility(g, llvm::Visibility::Hidden);
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}
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g
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} else {
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check_and_apply_linkage(self, fn_attrs, llty, sym, def_id)
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};
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|
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// Thread-local statics in some other crate need to *always* be linked
|
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// against in a thread-local fashion, so we need to be sure to apply the
|
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// thread-local attribute locally if it was present remotely. If we
|
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// don't do this then linker errors can be generated where the linker
|
|
// complains that one object files has a thread local version of the
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// symbol and another one doesn't.
|
|
if fn_attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL) {
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llvm::set_thread_local_mode(g, self.tls_model);
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}
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let dso_local = self.assume_dso_local(g, true);
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|
|
|
if !def_id.is_local() {
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let needs_dll_storage_attr = self.use_dll_storage_attrs
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&& !self.tcx.is_foreign_item(def_id)
|
|
// Local definitions can never be imported, so we must not apply
|
|
// the DLLImport annotation.
|
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&& !dso_local
|
|
// Linker plugin ThinLTO doesn't create the self-dllimport Rust uses for rlibs
|
|
// as the code generation happens out of process. Instead we assume static linkage
|
|
// and disallow dynamic linking when linker plugin based LTO is enabled.
|
|
// Regular in-process ThinLTO doesn't need this workaround.
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&& !self.tcx.sess.opts.cg.linker_plugin_lto.enabled();
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|
|
|
// If this assertion triggers, there's something wrong with commandline
|
|
// argument validation.
|
|
assert!(
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!(self.tcx.sess.opts.cg.linker_plugin_lto.enabled()
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&& self.tcx.sess.target.is_like_windows
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&& self.tcx.sess.opts.cg.prefer_dynamic)
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);
|
|
|
|
if needs_dll_storage_attr {
|
|
// This item is external but not foreign, i.e., it originates from an external Rust
|
|
// crate. Since we don't know whether this crate will be linked dynamically or
|
|
// statically in the final application, we always mark such symbols as 'dllimport'.
|
|
// If final linkage happens to be static, we rely on compiler-emitted __imp_ stubs
|
|
// to make things work.
|
|
//
|
|
// However, in some scenarios we defer emission of statics to downstream
|
|
// crates, so there are cases where a static with an upstream DefId
|
|
// is actually present in the current crate. We can find out via the
|
|
// is_codegened_item query.
|
|
if !self.tcx.is_codegened_item(def_id) {
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llvm::set_dllimport_storage_class(g);
|
|
}
|
|
}
|
|
}
|
|
|
|
if self.use_dll_storage_attrs
|
|
&& let Some(library) = self.tcx.native_library(def_id)
|
|
&& library.kind.is_dllimport()
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{
|
|
// For foreign (native) libs we know the exact storage type to use.
|
|
llvm::set_dllimport_storage_class(g);
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}
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|
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self.instances.borrow_mut().insert(instance, g);
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g
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}
|
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|
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fn codegen_static_item(&self, def_id: DefId) {
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unsafe {
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assert!(
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llvm::LLVMGetInitializer(
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self.instances.borrow().get(&Instance::mono(self.tcx, def_id)).unwrap()
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|
)
|
|
.is_none()
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);
|
|
let attrs = self.tcx.codegen_fn_attrs(def_id);
|
|
|
|
let Ok((v, alloc)) = codegen_static_initializer(self, def_id) else {
|
|
// Error has already been reported
|
|
return;
|
|
};
|
|
let alloc = alloc.inner();
|
|
|
|
let val_llty = self.val_ty(v);
|
|
|
|
let g = self.get_static_inner(def_id, val_llty);
|
|
let llty = llvm::LLVMGlobalGetValueType(g);
|
|
|
|
let g = if val_llty == llty {
|
|
g
|
|
} else {
|
|
// codegen_static_initializer creates the global value just from the
|
|
// `Allocation` data by generating one big struct value that is just
|
|
// all the bytes and pointers after each other. This will almost never
|
|
// match the type that the static was declared with. Unfortunately
|
|
// we can't just LLVMConstBitCast our way out of it because that has very
|
|
// specific rules on what can be cast. So instead of adding a new way to
|
|
// generate static initializers that match the static's type, we picked
|
|
// the easier option and retroactively change the type of the static item itself.
|
|
let name = llvm::get_value_name(g).to_vec();
|
|
llvm::set_value_name(g, b"");
|
|
|
|
let linkage = llvm::get_linkage(g);
|
|
let visibility = llvm::get_visibility(g);
|
|
|
|
let new_g = llvm::LLVMRustGetOrInsertGlobal(
|
|
self.llmod,
|
|
name.as_c_char_ptr(),
|
|
name.len(),
|
|
val_llty,
|
|
);
|
|
|
|
llvm::set_linkage(new_g, linkage);
|
|
llvm::set_visibility(new_g, visibility);
|
|
|
|
// The old global has had its name removed but is returned by
|
|
// get_static since it is in the instance cache. Provide an
|
|
// alternative lookup that points to the new global so that
|
|
// global_asm! can compute the correct mangled symbol name
|
|
// for the global.
|
|
self.renamed_statics.borrow_mut().insert(def_id, new_g);
|
|
|
|
// To avoid breaking any invariants, we leave around the old
|
|
// global for the moment; we'll replace all references to it
|
|
// with the new global later. (See base::codegen_backend.)
|
|
self.statics_to_rauw.borrow_mut().push((g, new_g));
|
|
new_g
|
|
};
|
|
set_global_alignment(self, g, alloc.align);
|
|
llvm::set_initializer(g, v);
|
|
|
|
self.assume_dso_local(g, true);
|
|
|
|
// Forward the allocation's mutability (picked by the const interner) to LLVM.
|
|
if alloc.mutability.is_not() {
|
|
llvm::LLVMSetGlobalConstant(g, llvm::True);
|
|
}
|
|
|
|
debuginfo::build_global_var_di_node(self, def_id, g);
|
|
|
|
if attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL) {
|
|
llvm::set_thread_local_mode(g, self.tls_model);
|
|
}
|
|
|
|
// Wasm statics with custom link sections get special treatment as they
|
|
// go into custom sections of the wasm executable. The exception to this
|
|
// is the `.init_array` section which are treated specially by the wasm linker.
|
|
if self.tcx.sess.target.is_like_wasm
|
|
&& attrs
|
|
.link_section
|
|
.map(|link_section| !link_section.as_str().starts_with(".init_array"))
|
|
.unwrap_or(true)
|
|
{
|
|
if let Some(section) = attrs.link_section {
|
|
let section = llvm::LLVMMDStringInContext2(
|
|
self.llcx,
|
|
section.as_str().as_c_char_ptr(),
|
|
section.as_str().len(),
|
|
);
|
|
assert!(alloc.provenance().ptrs().is_empty());
|
|
|
|
// The `inspect` method is okay here because we checked for provenance, and
|
|
// because we are doing this access to inspect the final interpreter state (not
|
|
// as part of the interpreter execution).
|
|
let bytes =
|
|
alloc.inspect_with_uninit_and_ptr_outside_interpreter(0..alloc.len());
|
|
let alloc =
|
|
llvm::LLVMMDStringInContext2(self.llcx, bytes.as_c_char_ptr(), bytes.len());
|
|
let data = [section, alloc];
|
|
let meta = llvm::LLVMMDNodeInContext2(self.llcx, data.as_ptr(), data.len());
|
|
let val = self.get_metadata_value(meta);
|
|
llvm::LLVMAddNamedMetadataOperand(
|
|
self.llmod,
|
|
c"wasm.custom_sections".as_ptr(),
|
|
val,
|
|
);
|
|
}
|
|
} else {
|
|
base::set_link_section(g, attrs);
|
|
}
|
|
|
|
base::set_variable_sanitizer_attrs(g, attrs);
|
|
|
|
if attrs.flags.contains(CodegenFnAttrFlags::USED) {
|
|
// `USED` and `USED_LINKER` can't be used together.
|
|
assert!(!attrs.flags.contains(CodegenFnAttrFlags::USED_LINKER));
|
|
|
|
// The semantics of #[used] in Rust only require the symbol to make it into the
|
|
// object file. It is explicitly allowed for the linker to strip the symbol if it
|
|
// is dead, which means we are allowed to use `llvm.compiler.used` instead of
|
|
// `llvm.used` here.
|
|
//
|
|
// Additionally, https://reviews.llvm.org/D97448 in LLVM 13 started emitting unique
|
|
// sections with SHF_GNU_RETAIN flag for llvm.used symbols, which may trigger bugs
|
|
// in the handling of `.init_array` (the static constructor list) in versions of
|
|
// the gold linker (prior to the one released with binutils 2.36).
|
|
//
|
|
// That said, we only ever emit these when compiling for ELF targets, unless
|
|
// `#[used(compiler)]` is explicitly requested. This is to avoid similar breakage
|
|
// on other targets, in particular MachO targets have *their* static constructor
|
|
// lists broken if `llvm.compiler.used` is emitted rather than `llvm.used`. However,
|
|
// that check happens when assigning the `CodegenFnAttrFlags` in
|
|
// `rustc_hir_analysis`, so we don't need to take care of it here.
|
|
self.add_compiler_used_global(g);
|
|
}
|
|
if attrs.flags.contains(CodegenFnAttrFlags::USED_LINKER) {
|
|
// `USED` and `USED_LINKER` can't be used together.
|
|
assert!(!attrs.flags.contains(CodegenFnAttrFlags::USED));
|
|
|
|
self.add_used_global(g);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'ll> StaticCodegenMethods for CodegenCx<'ll, '_> {
|
|
/// Get a pointer to a global variable.
|
|
///
|
|
/// The pointer will always be in the default address space. If global variables default to a
|
|
/// different address space, an addrspacecast is inserted.
|
|
fn static_addr_of(&self, cv: &'ll Value, align: Align, kind: Option<&str>) -> &'ll Value {
|
|
let gv = self.static_addr_of_impl(cv, align, kind);
|
|
// static_addr_of_impl returns the bare global variable, which might not be in the default
|
|
// address space. Cast to the default address space if necessary.
|
|
self.const_pointercast(gv, self.type_ptr())
|
|
}
|
|
|
|
fn codegen_static(&self, def_id: DefId) {
|
|
self.codegen_static_item(def_id)
|
|
}
|
|
|
|
/// Add a global value to a list to be stored in the `llvm.used` variable, an array of ptr.
|
|
fn add_used_global(&self, global: &'ll Value) {
|
|
self.used_statics.borrow_mut().push(global);
|
|
}
|
|
|
|
/// Add a global value to a list to be stored in the `llvm.compiler.used` variable,
|
|
/// an array of ptr.
|
|
fn add_compiler_used_global(&self, global: &'ll Value) {
|
|
self.compiler_used_statics.borrow_mut().push(global);
|
|
}
|
|
}
|