[llvm-readobj] - Teach readobj to print PT_OPENBSD_BOOTDATA header

[grimar]

Summary

These are OpenBSD specific program headers.

OpenBSD commit:
https://github.com/openbsd/src/commit/d39116912b9536bd77326260dc5c6e593fd4ee24

It is required for fixing PR31288.

[davide]

test/tools/llvm-readobj/program-headers.test

16–19

why did you have to change the linker script?

tools/llvm-readobj/ELFDumper.cpp

1161–1164

unsorted.

[grimar]

test/tools/llvm-readobj/program-headers.test

16–19

To add new program header 0x65a41be6 (PT_OPENBSD_BOOTDATA).

tools/llvm-readobj/ELFDumper.cpp

1161–1164

Sorted by value, linke in ELF.h and above.

[davide]

test/tools/llvm-readobj/program-headers.test

16–19

They look too magic (same for foo and bar). Please explain the mapping PT_OPENBSD_* -> number in a comment

[grimar]

• Addressed review comments.

[davide]

LGTM modulo nit.

test/tools/llvm-readobj/program-headers.test

17–19

Nit:
is *the* value of

[grimar]

test/tools/llvm-readobj/program-headers.test

17–19

Thanks !

test/tools/llvm-readobj/program-headers.test

 RUN: llvm-readobj -program-headers %p/../../Object/Inputs/program-headers.elf-i386 \
 RUN:     | FileCheck %s -check-prefix ELF-I386
 RUN: llvm-readobj -program-headers %p/../../Object/Inputs/program-headers.elf-x86-64 \
 RUN:     | FileCheck %s -check-prefix ELF-X86-64
 RUN: llvm-readobj -program-headers %p/../../Object/Inputs/program-headers.mips \
 RUN:     | FileCheck %s -check-prefix ELF-MIPS
 RUN: llvm-readobj -program-headers %p/../../Object/Inputs/program-headers.mips64 \
 RUN:     | FileCheck %s -check-prefix ELF-MIPS64
 
 ## openbsd-phdrs.elf-x86-64 was generated using GNU ld (GNU Binutils for Ubuntu) 2.26.1.
 ## llvm-mc -filetype=obj -triple=x86_64-pc-linux test.s -o main.o
 ## ld -script linker.script main.o -o openbsd-phdrs.elf-x86-64
 ##
 ## test.s is an empty file.
 ## linker.script:
-## PHDRS { text PT_LOAD FILEHDR PHDRS; foo 0x65a3dbe6; bar 0x65a3dbe7; }
+## PHDRS { text PT_LOAD FILEHDR PHDRS; foo 0x65a3dbe6; bar 0x65a3dbe7; zed 0x65a41be6; }
+##   Where 0x65a3dbe6 is a value of PT_OPENBSD_RANDOMIZE,
+##         0x65a3dbe7 is a value of PT_OPENBSD_WXNEEDED,
+##         0x65a41be6 is a value of PT_OPENBSD_BOOTDATA
 ## SECTIONS { . = SIZEOF_HEADERS; .all : { *(.*) } : text }
 RUN: llvm-readobj -program-headers %p/../../Object/Inputs/openbsd-phdrs.elf-x86-64 \
 RUN:     | FileCheck %s -check-prefix OPENBSD-X86-64
 
 ELF-I386:      ProgramHeaders [
 ELF-I386-NEXT:   ProgramHeader {
 ELF-I386-NEXT:     Type: PT_LOAD (0x1)
 ELF-I386-NEXT:     Offset: 0x0

 OPENBSD-X86-64-NEXT:     VirtualAddress:
 OPENBSD-X86-64-NEXT:     PhysicalAddress:
 OPENBSD-X86-64-NEXT:     FileSize:
 OPENBSD-X86-64-NEXT:     MemSize:
 OPENBSD-X86-64-NEXT:     Flags [
 OPENBSD-X86-64-NEXT:     ]
 OPENBSD-X86-64-NEXT:     Alignment:
 OPENBSD-X86-64-NEXT:   }
+OPENBSD-X86-64-NEXT:   ProgramHeader {
+OPENBSD-X86-64-NEXT:     Type:  PT_OPENBSD_BOOTDATA
+OPENBSD-X86-64-NEXT:     Offset:
+OPENBSD-X86-64-NEXT:     VirtualAddress:
+OPENBSD-X86-64-NEXT:     PhysicalAddress:
+OPENBSD-X86-64-NEXT:     FileSize:
+OPENBSD-X86-64-NEXT:     MemSize:
+OPENBSD-X86-64-NEXT:     Flags [
+OPENBSD-X86-64-NEXT:     ]
+OPENBSD-X86-64-NEXT:     Alignment:
+OPENBSD-X86-64-NEXT:   }

tools/llvm-readobj/ELFDumper.cpp

static const char *getElfSegmentType(unsigned Arch, unsigned Type) {
   LLVM_READOBJ_ENUM_CASE(ELF, PT_TLS    );
 
   LLVM_READOBJ_ENUM_CASE(ELF, PT_GNU_EH_FRAME);
   LLVM_READOBJ_ENUM_CASE(ELF, PT_SUNW_UNWIND);
 
   LLVM_READOBJ_ENUM_CASE(ELF, PT_GNU_STACK);
   LLVM_READOBJ_ENUM_CASE(ELF, PT_GNU_RELRO);
 
   LLVM_READOBJ_ENUM_CASE(ELF, PT_OPENBSD_RANDOMIZE);
   LLVM_READOBJ_ENUM_CASE(ELF, PT_OPENBSD_WXNEEDED);
+  LLVM_READOBJ_ENUM_CASE(ELF, PT_OPENBSD_BOOTDATA);
 
   default: return "";
   }
 }
 
 static std::string getElfPtType(unsigned Arch, unsigned Type) {
   switch (Type) {
     LLVM_READOBJ_PHDR_ENUM(ELF, PT_NULL)
     LLVM_READOBJ_PHDR_ENUM(ELF, PT_LOAD)