[clang] [llvm] [MC,llvm-readobj,yaml2obj] Support CREL relocation format (PR #91280)

[Fangrui Song via llvm-commits]

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@@ -32,12 +32,17 @@ FileHeader:
 # RUN:     --match-full-lines --check-prefixes=GNU-RELOCS,GNU-PLTRELA
 
 # LLVM-RELOCS:      Dynamic Relocations {
+# LLVM-RELOCS-NEXT:   0x8 R_X86_64_64 foo 0x0
 # LLVM-RELOCS-NEXT:   0x1 R_X86_64_NONE foo 0x0
 # LLVM-RELOCS-NEXT:   0x2 R_X86_64_NONE foo
-# LLVM-RELOCS-NEXT:   0x4 R_X86_64_RELATIVE
+# LLVM-RELOCS-NEXT:   0x4 R_X86_64_RELATIVE -
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MaskRay wrote:

llvm-readobj (LLVM style) displays `-` when the symbol index is 0.
This line in the absence of the patch contains a `-` as well.

https://github.com/llvm/llvm-project/pull/91280