[lld] [lld-macho] Implement support for ObjC relative method lists (PR #86231)

[Kyungwoo Lee via llvm-commits]

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@@ -0,0 +1,211 @@
+# REQUIRES: aarch64
+# RUN: rm -rf %t; split-file %s %t && cd %t
+
+## Compile a64_rel_dylib.o
+# RUN: llvm-mc -filetype=obj -triple=arm64-apple-macos -o a64_rel_dylib.o a64_simple_class.s
+
+## Test arm64 + relative method lists
+# RUN: ld64.lld a64_rel_dylib.o -o a64_rel_dylib.dylib -map a64_rel_dylib.map -dylib -arch arm64 -platform_version macos 11.0.0 11.0.0 -objc_relative_method_lists
+# RUN: llvm-objdump --macho --objc-meta-data a64_rel_dylib.dylib  | FileCheck %s --check-prefix=CHK_REL
+
+## Test arm64 + traditional method lists (no relative offsets)
+# RUN: ld64.lld a64_rel_dylib.o -o a64_rel_dylib.dylib -map a64_rel_dylib.map -dylib -arch arm64 -platform_version macos 11.0.0 11.0.0 -no_objc_relative_method_lists
+# RUN: llvm-objdump --macho --objc-meta-data a64_rel_dylib.dylib  | FileCheck %s --check-prefix=CHK_NO_REL
+
+CHK_NO_REL-NOT: (relative)
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kyulee-com wrote:

I don't see other checks with `CHK_NO_REL` other than this line. Can we check the original output of method lists?

https://github.com/llvm/llvm-project/pull/86231