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

[Chen Zheng via llvm-commits]

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@@ -387,7 +387,7 @@ entry:
 ; ASM64BIT:       bl .test_byval_mem4
 ; ASM64BIT:       addi 1, 1, 352
 
-define void @test_byval_mem4(i32, ptr byval(%struct_S31) align 1, ptr byval(%struct_S256) align 1 %s) {
+define void @test_byval_mem4(i32, ptr byval(%struct_S31) align 1, ptr byval(%struct_S256) align 1 %s) #0 {
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chenzheng1030 wrote:

Other case changes related to unwind attribute should also be unnecessary?

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