[MachineOutliner] Don't outline ADRP pair to avoid incorrect ICF (#160232) On AArch64, ADRP and its user instructions (LDR, ADD, etc.), that are referencing a GOT symbol, when separated into different functions by machine outliner exposes a correctness issue in the linker ICF. In such cases, user instructions can end up pointing to a folded section (with its canonical folded symbol), while ADRP instruction point to a GOT entry corresponding to the original symbol. This leads to loading from incorrect memory address after ICF. #129122 explains how this can happen in detail. This addresses #131660 which should fix two things: 1. Hide the correctness issue described above in the LLVM linker. 2. Allows optimizations that could relax GOT addressing to PC-relative addressing.
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