rust/tests/codegen-llvm
Jacob Pratt a7a4e17225
Rollup merge of #145064 - okaneco:saturating_sub_regression_tests, r=nikic
Add regression test for `saturating_sub` bounds check issue

Add codegen test for issue where `valid_index.saturating_sub(X)` produced an extra bounds check.
This was fixed by the LLVM upgrade.

Closes rust-lang/rust#139759
2025-08-10 15:43:53 -04:00
..

The files here use the LLVM FileCheck framework, documented at https://llvm.org/docs/CommandGuide/FileCheck.html.

One extension worth noting is the use of revisions as custom prefixes for FileCheck. If your codegen test has different behavior based on the chosen target or different compiler flags that you want to exercise, you can use a revisions annotation, like so:

// revisions: aaa bbb
// [bbb] compile-flags: --flags-for-bbb

After specifying those variations, you can write different expected, or explicitly unexpected output by using <prefix>-SAME: and <prefix>-NOT:, like so:

// CHECK: expected code
// aaa-SAME: emitted-only-for-aaa
// aaa-NOT:                        emitted-only-for-bbb
// bbb-NOT:  emitted-only-for-aaa
// bbb-SAME:                       emitted-only-for-bbb