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Merge finalize_function and perform_relocations

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This commit is contained in:
bjorn3
2020-11-09 09:39:36 +01:00
parent 9ced345aed
commit d0706e6f71
1 changed files with 11 additions and 51 deletions
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62
cranelift/simplejit/src/backend.rs
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@@ -291,13 +291,9 @@ impl SimpleJITModule {
}
}
fn finalize_function(&mut self, id: FuncId) {
fn perform_relocations(&self, blob: &CompiledBlob) {
use std::ptr::write_unaligned;
let func = self.functions[id]
.as_ref()
.expect("function must be compiled before it can be finalized");
for &RelocRecord {
reloc,
offset,
@@ -305,8 +301,8 @@ impl SimpleJITModule {
addend,
} in &func.relocs
{
debug_assert!((offset as usize) < func.size);
let at = unsafe { func.ptr.offset(offset as isize) };
debug_assert!((offset as usize) < blob.size);
let at = unsafe { blob.ptr.offset(offset as isize) };
let base = self.get_definition(name);
// TODO: Handle overflow.
let what = unsafe { base.offset(addend as isize) };
@@ -338,48 +334,6 @@ impl SimpleJITModule {
}
}
fn finalize_data(&mut self, id: DataId) {
use std::ptr::write_unaligned;
let data = self.data_objects[id]
.as_ref()
.expect("data object must be compiled before it can be finalized");
for &RelocRecord {
reloc,
offset,
ref name,
addend,
} in &data.relocs
{
debug_assert!((offset as usize) < data.size);
let at = unsafe { data.ptr.offset(offset as isize) };
let base = self.get_definition(name);
// TODO: Handle overflow.
let what = unsafe { base.offset(addend as isize) };
match reloc {
Reloc::Abs4 => {
// TODO: Handle overflow.
#[cfg_attr(feature = "cargo-clippy", allow(clippy::cast_ptr_alignment))]
unsafe {
write_unaligned(at as *mut u32, what as u32)
};
}
Reloc::Abs8 => {
#[cfg_attr(feature = "cargo-clippy", allow(clippy::cast_ptr_alignment))]
unsafe {
write_unaligned(at as *mut u64, what as u64)
};
}
Reloc::X86PCRel4
| Reloc::X86CallPCRel4
| Reloc::X86GOTPCRel4
| Reloc::X86CallPLTRel4 => panic!("unexpected text relocation in data"),
_ => unimplemented!(),
}
}
}
/// Finalize all functions and data objects that are defined but not yet finalized.
/// All symbols referenced in their bodies that are declared as needing a definition
/// must be defined by this point.
@@ -390,12 +344,18 @@ impl SimpleJITModule {
for func in std::mem::take(&mut self.functions_to_finalize) {
let decl = self.declarations.get_function_decl(func);
debug_assert!(decl.linkage.is_definable());
self.finalize_function(func);
let func = self.functions[func]
.as_ref()
.expect("function must be compiled before it can be finalized");
self.perform_relocations(func);
}
for data in std::mem::take(&mut self.data_objects_to_finalize) {
let decl = self.declarations.get_data_decl(data);
debug_assert!(decl.linkage.is_definable());
self.finalize_data(data);
let data = self.data_objects[data]
.as_ref()
.expect("data object must be compiled before it can be finalized");
self.perform_relocations(data);
}
// Now that we're done patching, prepare the memory for execution!