[lld] [lld][ELF] Implement merged .debug_names section. (PR #86508)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,189 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64 %s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64 %p/Inputs/debug-names-2.s -o %t2.o
+# RUN: ld.lld --debug-names %t1.o %t2.o -o %t
+
+# RUN: llvm-dwarfdump -debug-names %t | FileCheck %s --check-prefix=DWARF
+
+# DWARF:      .debug_names contents:
+# DWARF:      Name Index @ 0x0 {
+# DWARF-NEXT:   Header {
+# DWARF-NEXT:     Length: 0xCC
+# DWARF-NEXT:     Format: DWARF32
+# DWARF-NEXT:     Version: 5
+# DWARF-NEXT:     CU count: 2
+# DWARF-NEXT:     Local TU count: 0
+# DWARF-NEXT:     Foreign TU count: 0
+# DWARF-NEXT:     Bucket count: 5
+# DWARF-NEXT:     Name count: 5
+# DWARF-NEXT:     Abbreviations table size: 0x1F
+# DWARF-NEXT:     Augmentation: '        '
+# DWARF:        Compilation Unit offsets [
+# DWARF-NEXT:     CU[0]: 0x00000000
+# DWARF-NEXT:     CU[1]: 0x00000041
+
+##
----------------
MaskRay wrote:

We typically place such file-level comments at the top. Don't add `^##$` lines.
Follow the convention of recent test files.

https://github.com/llvm/llvm-project/pull/86508