[lld] [lld] Merge equivalent symbols found during ICF (PR #134342)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,68 @@
+// REQUIRES: aarch64
+
+# RUN: llvm-mc -filetype=obj -triple=aarch64 %s -o %t
+# RUN: ld.lld %t -o %t2 --icf=all
+# RUN: llvm-objdump --section-headers %t2 | FileCheck %s --check-prefix=EXE
+
+# RUN: ld.lld -shared %t -o %t3 --icf=all
+# RUN: llvm-objdump --section-headers %t3 | FileCheck %s --check-prefix=DSO
+
+## All .rodata.* sections should merge into a single GOT entry
+# EXE: {{.*}}.got 00000008{{.*}}
+
+## When symbols are preemptible in DSO mode, GOT entries wouldn't be merged
+# DSO: {{.*}}.got 00000020{{.*}}
+
+.addrsig
+
+callee:
+ret
+
+.section .rodata.dummy1,"a", at progbits
+sym1:
+.long 111
+.long 122
+.byte 123
+
+.section .rodata.dummy2,"a", at progbits
+sym2:
+.long 111
+.long 122
+sym3:
+.byte 123
+
+.macro f, index
+
+.section .text.f1_\index,"ax", at progbits
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MaskRay wrote:

Retain my code comment in https://github.com/llvm/llvm-project/issues/129122#issuecomment-2739009435

https://github.com/llvm/llvm-project/pull/134342