[llvm] [PowerPC] Spill non-volatile registers required for traceback table (PR #71115)

[Chen Zheng via llvm-commits]

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@@ -199,3 +293,4 @@ define dso_local void @all_fprs_and_vecregs() {
 ; MIR64-NOT:     $v29
 ; MIR64-NOT:     $v30
 ; MIR64-NOT:     $v31
+attributes #0 = { nounwind }
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chenzheng1030 wrote:

unnecessary? And also the functions that use this attribute.

https://github.com/llvm/llvm-project/pull/71115