Files
rust/tests/codegen-llvm
bors db3e99bbab Auto merge of #150605 - RalfJung:fallback-intrinsic-skip, r=mati865
skip codegen for intrinsics with big fallback bodies if backend does not need them

This hopefully fixes the perf regression from https://github.com/rust-lang/rust/pull/148478. I only added the intrinsics with big fallback bodies to the list; it doesn't seem worth the effort of going through the entire list.

Fixes https://github.com/rust-lang/rust/issues/149945
Cc @scottmcm @bjorn3
2026-02-04 17:12:58 +00:00
..
2025-11-08 10:57:35 -07:00
2026-01-27 10:43:21 -08:00
2025-08-15 16:42:21 +00:00

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