[llvm] PowerPC32:PIC: Update to bcl to fix branch prediction mis-predict issue (PR #134140)

[via llvm-commits]

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@@ -18,8 +18,8 @@ entry:
 ; SMALL-LABEL: foo:
 ; SMALL:         stwu 1, -32(1)
 ; SMALL:         stw 30, 24(1)
-; SMALL-BSS:     bl _GLOBAL_OFFSET_TABLE_ at local-4
-; SMALL-SECURE:  bl .L0$pb
+; SMALL-BSS:     bcl 20, 31, _GLOBAL_OFFSET_TABLE_ at local-4
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chleroy wrote:

I think this change is not valid. Allthough it will likely work, it is expected to use 'bl' for unconditionnal calls, as there will be a return instruction at the called address.

Only 'bl +.4' is to be replaced by 'bcl 20,31,+.4', nothing else. 

https://github.com/llvm/llvm-project/pull/134140