Skip to content

Emit the enum range assumption if the range only contains one element #83020

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Mar 13, 2021
Merged

Emit the enum range assumption if the range only contains one element #83020

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion compiler/rustc_codegen_ssa/src/mir/rvalue.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -325,7 +325,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {

let er = scalar.valid_range_exclusive(bx.cx());
if er.end != er.start
&& scalar.valid_range.end() > scalar.valid_range.start()
&& scalar.valid_range.end() >= scalar.valid_range.start()
{
// We want `table[e as usize ± k]` to not
// have bound checks, and this is the most
Expand Down
16 changes: 16 additions & 0 deletions src/test/codegen/enum-bounds-check-issue-82871.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,16 @@
// compile-flags: -O
// min-llvm-version: 11.0

#![crate_type = "lib"]

#[repr(C)]
pub enum E {
A,
}

// CHECK-LABEL: @index
#[no_mangle]
pub fn index(x: &[u32; 3], ind: E) -> u32{
// CHECK-NOT: panic_bounds_check
x[ind as usize]
}