[llvm] [llvm-objcopy] Fix file offsets when PT_INTERP/PT_LOAD offsets are equal (PR #80562)

[James Henderson via llvm-commits]

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@@ -0,0 +1,131 @@
+## When the offset of a non-PT_LOAD segment (e.g. PT_INTERP) equals the offset
+## of a PT_LOAD segment, set the parent of the PT_INTERP segment to the PT_LOAD
+## segment, ensuring that the offset is correctly aligned.
+
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy %t %t2
+# RUN: llvm-readelf -Sl %t2 | FileCheck %s
+
+# CHECK:       [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+# CHECK-NEXT:  [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
+# CHECK-NEXT:  [ 1] .text             PROGBITS        0000000000201000 001000 000001 00  AX  0   0  4
+# CHECK-NEXT:  [ 2] .interp           PROGBITS        0000000000202000 002000 00001c 00   A  0   0  1
+# CHECK-NEXT:  [ 3] .rodata           PROGBITS        0000000000202020 002020 000001 00   A  0   0  1
+# CHECK-NEXT:  [ 4] .tdata            PROGBITS        0000000000203000 003000 000001 00 WAT  0   0 4096
+# CHECK-NEXT:  [ 5] .relro_padding    NOBITS          0000000000203001 003001 000fff 00  WA  0   0  1
+# CHECK-NEXT:  [ 6] .strtab           STRTAB          0000000000000000 003001 000001 00      0   0  1
+# CHECK-NEXT:  [ 7] .shstrtab         STRTAB          0000000000000000 003002 00003f 00      0   0  1
+
+# CHECK:     Program Headers:
+# CHECK-NEXT:  Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
+# CHECK-NEXT:  PHDR           0x000040 0x0000000000200040 0x0000000000200040 0x0001c0 0x0001c0 R   0x8
+# CHECK-NEXT:  INTERP         0x002000 0x0000000000202000 0x0000000000202000 0x00001c 0x00001c R   0x1
+# CHECK-NEXT:      [Requesting program interpreter: /lib64/ld-linux-x86-64.so.2]
+# CHECK-NEXT:  LOAD           0x000000 0x0000000000200000 0x0000000000200000 0x000200 0x000200 R   0x1000
+# CHECK-NEXT:  LOAD           0x001000 0x0000000000201000 0x0000000000201000 0x000001 0x000001 R E 0x1000
+# CHECK-NEXT:  LOAD           0x002000 0x0000000000202000 0x0000000000202000 0x000021 0x000021 R   0x1000
+# CHECK-NEXT:  TLS            0x003000 0x0000000000203000 0x0000000000203000 0x000001 0x001000 R   0x1000
+# CHECK-NEXT:  GNU_RELRO      0x003000 0x0000000000203000 0x0000000000203000 0x000001 0x001000 R   0x1000
+# CHECK-NEXT:  LOAD           0x003000 0x0000000000203000 0x0000000000203000 0x000001 0x001000 RW  0x1000
+
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+  Entry:           0x201000
+ProgramHeaders:
+  - Type:            PT_PHDR
+    Flags:           [ PF_R ]
----------------
jh7370 wrote:

If I'm not mistaken, the section and program header flags are all irrelevant to the test, so can be scrapped.

https://github.com/llvm/llvm-project/pull/80562