44942ad10f
adapt tests/codegen/vec-shrink-panik for LLVM 17
After 0d4a709bb8
LLVM now doesn't generate references to panic_cannot_unwind:
https://buildkite.com/llvm-project/rust-llvm-integrate-prototype/builds/17978#0186ff55-ca6f-4bc5-b1ec-2622c77d0ed5/744-746
Adapted as suggested by ````@nikic```` on Zulip:
https://rust-lang.zulipchat.com/#narrow/stream/187780-t-compiler.2Fwg-llvm/topic/a.20couple.20codegen.20test.20failures.20after.20llvm.200d4a709bb876824a/near/342664944
>Okay, so LLVM now realizes that double panic is not possible, so that's fine.
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