[lld] [ELF, test] Add test for R_AARCH64_* implicit addends (PR #87733)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,86 @@
+## Test certain REL relocation types generated by legacy armasm.
+# RUN: yaml2obj %s -o %t.o
+# RUN: not ld.lld %t.o -o /dev/null 2>&1 | FileCheck %s
+
+# CHECK-COUNT-17: internal linker error: cannot read addend
+
+---
+!ELF
+FileHeader:
+  Class: ELFCLASS64
+  Data: ELFDATA2LSB
+  Type: ET_REL
+  Machine: EM_AARCH64
+Sections:
+  - Name:    .abs
+    Type:    SHT_PROGBITS
+    Flags:   [ SHF_ALLOC ]
+    Content: fffffefffffffdfffffffffffffffcffffffffffffff
+  - Name:    .rel.abs
+    Type:    SHT_REL
+    Link:    .symtab
+    Info:    .abs
+    Relocations:
+      - {Offset: 0, Symbol: abs, Type: R_AARCH64_ABS16}
+      - {Offset: 2, Symbol: abs, Type: R_AARCH64_ABS32}
+      - {Offset: 6, Symbol: abs, Type: R_AARCH64_ABS64}
+      - {Offset: 14, Symbol: abs, Type: R_AARCH64_ADD_ABS_LO12_NC}
+
+  - Name:    .uabs
+    Type:    SHT_PROGBITS
+    Flags:   [ SHF_ALLOC ]
+    AddressAlign: 4
+    Content: 00ffffff00ffffff00ffffff00ffffff00ffffff00ffffff
+  - Name:    .rel.uabs
+    Type:    SHT_REL
+    Link:    .symtab
+    Info:    .uabs
+    Relocations:
+      - {Offset:  0, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G0}
+      - {Offset:  4, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G0_NC}
+      - {Offset:  8, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G1}
+      - {Offset: 12, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G1_NC}
+      - {Offset: 16, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G2}
+      - {Offset: 20, Symbol: abs, Type: R_AARCH64_MOVW_UABS_G2_NC}
+
+  - Name:    .prel
+    Type:    SHT_PROGBITS
+    Flags:   [ SHF_ALLOC ]
+    AddressAlign: 4
+    Content: 00ffffff00ffffff00ffffff00ffffff00ffffff00ffffff
+  - Name:    .rel.prel
+    Type:    SHT_REL
+    Link:    .symtab
+    Info:    .prel
+    Relocations:
+      - {Offset:  0, Symbol: .prel, Type: R_AARCH64_PREL64}
+      - {Offset:  4, Symbol: .prel, Type: R_AARCH64_PREL32}
----------------
MaskRay wrote:

I think it is fine to keep `relocation-rel-format.test` unchanged. That file shows that we support REL for certain targets.

https://github.com/llvm/llvm-project/pull/87733