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

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,100 @@
+# RUN: llvm-mc -filetype=obj -crel -triple=x86_64 %s -o %t.o
+# RUN: llvm-readelf -Sr -x .crelrodata2 -x .crelrodata16 %t.o | FileCheck %s
+
+# RUN: %if aarch64-registered-target %{ llvm-mc -filetype=obj -crel -triple=aarch64_be %s -o %t.be.o %}
+# RUN: %if aarch64-registered-target %{ llvm-readelf -r %t.be.o | FileCheck %s --check-prefix=A64BE %}
+
+# CHECK:      [ 4] .data             PROGBITS      0000000000000000 {{.*}} 000008 00  WA  0   0  1
+# CHECK-NEXT: [ 5] .crel.data        CREL          0000000000000000 {{.*}} 00002a 01   I 14   4  1
+# CHECK-NEXT: [ 6] .rodata           PROGBITS      0000000000000000 {{.*}} 00002b 00   A  0   0  1
+# CHECK-NEXT: [ 7] .crel.rodata      CREL          0000000000000000 {{.*}} 000010 01   I 14   6  1
+# CHECK-NEXT: [ 8] rodata2           PROGBITS      0000000000000000 {{.*}} 000008 00   A  0   0  1
+# CHECK-NEXT: [ 9] .crelrodata2      CREL          0000000000000000 {{.*}} 000005 01   I 14   8  1
+# CHECK-NEXT: [10] rodata16          PROGBITS      0000000000000000 {{.*}} 000010 00   A  0   0  1
+# CHECK-NEXT: [11] .crelrodata16     CREL          0000000000000000 {{.*}} 000004 01   I 14  10  1
+# CHECK-NEXT: [12] noalloc           PROGBITS      0000000000000000 {{.*}} 000004 00      0   0  1
+# CHECK-NEXT: [13] .crelnoalloc      CREL          0000000000000000 {{.*}} 000005 01   I 14  12  1
+# CHECK-NEXT: [14] .symtab           SYMTAB
+
+# CHECK:      Relocation section '.crel.data' at offset {{.*}} contains 7 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 0000000000000000  {{.*}}           R_X86_64_NONE          0000000000000000 a0 + 0
+# CHECK-NEXT: 0000000000000001  {{.*}}           R_X86_64_NONE          0000000000000000 a1 - 1
+# CHECK-NEXT: 0000000000000002  {{.*}}           R_X86_64_NONE          0000000000000000 a2 - 1
+# CHECK-NEXT: 0000000000000003  {{.*}}           R_X86_64_32            0000000000000000 a3 + 4000
+# CHECK-NEXT: 0000000000000004  {{.*}}           R_X86_64_64            0000000000000000 a0 - 8000000000000000
+# CHECK-NEXT: 0000000000000005  {{.*}}           R_X86_64_64            0000000000000000 a1 + 7fffffffffffffff
+# CHECK-NEXT: 0000000000000005  {{.*}}           R_X86_64_32            0000000000000000 a1 - 1
+# CHECK-EMPTY:
+# CHECK-NEXT: Relocation section '.crel.rodata' at offset {{.*}} contains 4 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 0000000000000000  {{.*}}           R_X86_64_PC32          0000000000000000 foo + 0
+# CHECK-NEXT: 000000000000000f  {{.*}}           R_X86_64_PC32          0000000000000000 foo + 3f
+# CHECK-NEXT: 000000000000001f  {{.*}}           R_X86_64_PC64          0000000000000000 foo + 7f
+# CHECK-NEXT: 0000000000000027  {{.*}}           R_X86_64_PC32          0000000000000000 _start - 1f81
+# CHECK-EMPTY:
+# CHECK-NEXT: Relocation section '.crelrodata2' at offset {{.*}} contains 2 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 0000000000000002  {{.*}}           R_X86_64_32            0000000000000000 .data + 0
+# CHECK-NEXT: 0000000000000008  {{.*}}           R_X86_64_32            0000000000000000 .data + 0
+# CHECK-EMPTY:
+# CHECK-NEXT: Relocation section '.crelrodata16' at offset {{.*}} contains 1 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 0000000000000008  {{.*}}           R_X86_64_64            0000000000000000 rodata16 + 0
+# CHECK-EMPTY:
+# CHECK-NEXT: Relocation section '.crelnoalloc' at offset {{.*}} contains 1 entries:
+# CHECK-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 0000000000000000  {{.*}}           R_X86_64_32            0000000000000000 .text + 4
+
+## count * 8 + 4 + shift = 2*8+4+1 = 21
+# CHECK:      Hex dump of section '.crelrodata2':
+# CHECK-NEXT: 0x00000000 150b020a 18                         .
+## count * 8 + 4 + shift = 1*8+4+3 = 15
+# CHECK:      Hex dump of section '.crelrodata16':
+# CHECK-NEXT: 0x00000000 0f0b0301 .
+
+# A64BE:      0000000000000000  {{.*}}           R_AARCH64_NONE         0000000000000000 a0 + 0
+# A64BE-NEXT: 0000000000000001  {{.*}}           R_AARCH64_NONE         0000000000000000 a1 - 1
+# A64BE-NEXT: 0000000000000002  {{.*}}           R_AARCH64_NONE         0000000000000000 a2 - 1
+# A64BE-NEXT: 0000000000000003  {{.*}}           R_AARCH64_ABS32        0000000000000000 a3 + 4000
+# A64BE-NEXT: 0000000000000004  {{.*}}           R_AARCH64_ABS64        0000000000000000 a0 - 8000000000000000
+# A64BE-NEXT: 0000000000000005  {{.*}}           R_AARCH64_ABS64        0000000000000000 a1 + 7fffffffffffffff
+# A64BE-NEXT: 0000000000000005  {{.*}}           R_AARCH64_ABS32        0000000000000000 a1 - 1
+
+.globl _start
+_start:
+  ret
+
+.section .text.1,"ax"
+  ret
+
+.data
+.reloc .+0, BFD_RELOC_NONE, a0
----------------
MaskRay wrote:

Improved the test further and added some comments.

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