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

[Peter Smith via llvm-commits]

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@@ -0,0 +1,180 @@
+# RUN: yaml2obj --docnum=1 %s -o %t
+# RUN: llvm-readobj -r %t | FileCheck %s --check-prefix=LLVM --match-full-lines
+# RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=GNU --match-full-lines
+
+# LLVM:      Relocations [
+# LLVM-NEXT:   Section ([[#]]) .crel.text {
+# LLVM-NEXT:     0x1 R_X86_64_32 g1 0x1
+# LLVM-NEXT:     0x2 R_X86_64_64 l1 0x2
+# LLVM-NEXT:     0x0 R_X86_64_32S g1 0xFFFFFFFFFFFFFFFF
+# LLVM-NEXT:     0x4 R_X86_64_32S .text 0x8000000000000000
+# LLVM-NEXT:   }
+# LLVM-NEXT:   Section ([[#]]) .crelnonalloc {
+# LLVM-NEXT:     0x10 R_X86_64_64 g1 0x1
+# LLVM-NEXT:     0x20 R_X86_64_64 g2 0x2
+# LLVM-NEXT:   }
+# LLVM-NEXT: ]
+
+# GNU:      Relocation section '.crel.text' at offset 0x48 contains 4 entries:
+# GNU-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# GNU-NEXT: 0000000000000001  000000030000000a R_X86_64_32            0000000000000000 g1 + 1
+# GNU-NEXT: 0000000000000002  0000000200000001 R_X86_64_64            0000000000000000 l1 + 2
+# GNU-NEXT: 0000000000000000  000000030000000b R_X86_64_32S           0000000000000000 g1 - 1
+# GNU-NEXT: 0000000000000004  000000010000000b R_X86_64_32S           0000000000000000 .text - 8000000000000000
+# GNU-EMPTY:
+# GNU-NEXT: Relocation section '.crelnonalloc' at offset 0xa2 contains 2 entries:
+# GNU-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# GNU-NEXT: 0000000000000010  0000000300000001 R_X86_64_64            0000000000000000 g1 + 1
+# GNU-NEXT: 0000000000000020  0000000400000001 R_X86_64_64            0000000000000000 g2 + 2
+
+--- !ELF
+FileHeader: !FileHeader
+  Class: ELFCLASS64
+  Data: ELFDATA2LSB
+  Type: ET_REL
+  Machine: EM_X86_64
+
+Sections:
+- Name: .text
+  Type: SHT_PROGBITS
+  Content: "0000000000000000"
+  Flags: [SHF_ALLOC]
+- Name: .crel.text
+  Type: SHT_CREL
+  Info: .text
+  Link: .symtab
+  Relocations:
+    - Offset: 0x1
+      Symbol: g1
+      Type:   R_X86_64_32
+      Addend: 1
+    - Offset: 0x2
+      Symbol: l1
+      Type:   R_X86_64_64
+      Addend: 2
+    - Offset: 0x0
+      Symbol: g1
+      Type:   R_X86_64_32S
+      Addend: 0xffffffffffffffff
+    - Offset: 0x4
+      Symbol: .text
+      Type:   R_X86_64_32S
+      Addend: 0x8000000000000000
+- Name: nonalloc
+  Type: SHT_PROGBITS
+  Size: 0x30
+- Name: .crelnonalloc
+  Type: SHT_CREL
+  Info: nonalloc
+  Link: .symtab
+  Relocations:
+    - Offset: 0x10
+      Symbol: g1
+      Type:   R_X86_64_64
+      Addend: 1
+    - Offset: 0x20
+      Symbol: g2
+      Type:   R_X86_64_64
+      Addend: 2
+
+Symbols:
+  - Name: .text
+    Type: STT_SECTION
+    Section: .text
+  - Name:    l1
+  - Name:    g1
+    Section: .text
+    Value:   0x0
+    Size:    4
+    Binding: STB_GLOBAL
+  - Name:    g2
+    Binding: STB_GLOBAL
+
+## Check relocation formatting on ELFCLASS32 as well.
----------------
smithp35 wrote:

It would be good to have a test for a target that doesn't have addends here too. 

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