user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add 0..=isize::MAX range metadata to size loads from vtables

Browse source
This commit is contained in:
Erik Desjardins 2022-12-08 01:30:07 -05:00
parent 023b5136b5
commit a99e97af97
5 changed files with 79 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

12
compiler/rustc_abi/src/lib.rs
View file

@ -775,6 +775,18 @@ impl Integer {
}
}
/// Returns the largest signed value that can be represented by this Integer.
#[inline]
pub fn signed_max(self) -> i128 {
match self {
I8 => i8::MAX as i128,
I16 => i16::MAX as i128,
I32 => i32::MAX as i128,
I64 => i64::MAX as i128,
I128 => i128::MAX,
}
}
/// Finds the smallest Integer type which can represent the signed value.
#[inline]
pub fn fit_signed(x: i128) -> Integer {

3
compiler/rustc_codegen_ssa/src/glue.rs
View file

@ -29,6 +29,9 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
let align = meth::VirtualIndex::from_index(ty::COMMON_VTABLE_ENTRIES_ALIGN)
.get_usize(bx, vtable);
// Size is always <= isize::MAX.
let size_bound = bx.data_layout().ptr_sized_integer().signed_max() as u128;
bx.range_metadata(size, WrappingRange { start: 0, end: size_bound });
// Alignment is always nonzero.
bx.range_metadata(align, WrappingRange { start: 1, end: !0 });

12
compiler/rustc_codegen_ssa/src/mir/intrinsic.rs
View file

@ -110,10 +110,16 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
_ => bug!(),
};
let value = meth::VirtualIndex::from_index(idx).get_usize(bx, vtable);
if name == sym::vtable_align {
match name {
// Size is always <= isize::MAX.
sym::vtable_size => {
let size_bound = bx.data_layout().ptr_sized_integer().signed_max() as u128;
bx.range_metadata(value, WrappingRange { start: 0, end: size_bound });
},
// Alignment is always nonzero.
bx.range_metadata(value, WrappingRange { start: 1, end: !0 });
};
sym::vtable_align => bx.range_metadata(value, WrappingRange { start: 1, end: !0 }),
_ => {}
}
value
}
sym::pref_align_of