[dsymutil] Emit real dSYM companion binaries.

The binaries containing the linked DWARF generated by dsymutil are not
standard relocatable object files like emitted did previsously. They should be
dSYM companion files, which means they have a different file type in the
header, but also a couple other peculiarities:
 - they contain the segments and sections from the original binary in their
load commands, but not the actual contents. This means they get an address
and a size, but their offset is always 0 (but these are not virtual sections)
 - they also conatin all the defined symbols from the original binary

This makes MC a really bad fit to emit these kind of binaries. The approach
that was used in this patch is to leverage MC's section layout for the
debug sections, but to use a replacement for MachObjectWriter that lives
in MachOUtils.cpp. Some of the low-level helpers from MachObjectWriter
were reused too.

llvm-svn: 246012

2 files changed, 339 insertions, 0 deletions

diff --git a/llvm/test/tools/dsymutil/Inputs/basic.macho.i386 b/llvm/test/tools/dsymutil/Inputs/basic.macho.i386
new file mode 100755
index 00000000000..ee6be096fe5
--- /dev/null
+++ b/llvm/test/tools/dsymutil/Inputs/basic.macho.i386
diff --git a/llvm/test/tools/dsymutil/X86/dsym-companion.test b/llvm/test/tools/dsymutil/X86/dsym-companion.test
new file mode 100644
index 00000000000..4327a2953d9
--- /dev/null
+++ b/llvm/test/tools/dsymutil/X86/dsym-companion.test
@@ -0,0 +1,339 @@
+RUN: llvm-dsymutil -o - %p/../Inputs/basic.macho.i386 -f | llvm-readobj -file-headers -program-headers -sections -symbols - | FileCheck %s -check-prefix=CHECK -check-prefix=CHECK32
+RUN: llvm-dsymutil -o - -oso-prepend-path=%p/.. %p/../Inputs/basic.macho.x86_64 -f | llvm-readobj -file-headers -program-headers -sections -symbols - | FileCheck %s -check-prefix=CHECK -check-prefix=CHECK64
+
+This test checks that the dSYM companion binaries generated in 32 and 64 bits
+are correct. The check are pretty strict (we check even the offsets and sizes
+of the sections) in order to test the VM address layout algorithm. As the
+debug sections are generated, this is a bit risky, but I don't expect
+llvm-dsymutil's output to change much for these tiny C programs so this should
+be OK.
+The 32bits version doesn't have object files, thus it has basically no debug
+sections.
+
+CHECK32: Format: Mach-O 32-bit i386
+CHECK32: Arch: i386
+CHECK32: AddressSize: 32bit
+CHECK64: Format: Mach-O 64-bit x86-64
+CHECK64: Arch: x86_64
+CHECK64: AddressSize: 64bit
+CHECK:   MachHeader {
+CHECK32:   Magic: Magic (0xFEEDFACE)
+CHECK32:   CpuType: X86 (0x7)
+CHECK32:   CpuSubType: CPU_SUBTYPE_I386_ALL (0x3)
+CHECK64:   Magic: Magic64 (0xFEEDFACF)
+CHECK64:   CpuType: X86-64 (0x1000007)
+CHECK64:   CpuSubType: CPU_SUBTYPE_X86_64_ALL (0x3)
+CHECK:     FileType: DWARFSymbol (0xA)
+CHECK:     NumOfLoadCommands: 7
+CHECK:     Flags [ (0x0)
+CHECK:   }
+CHECK:   Sections [
+CHECK:     Section {
+CHECK:       Name: __text
+CHECK:       Segment: __TEXT
+CHECK32:     Address: 0x1E90
+CHECK32:     Size: 0x11A
+CHECK64:     Address: 0x100000EA0
+CHECK64:     Size: 0x109
+CHECK:       Offset: 0
+CHECK:       Alignment: 4
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: 0x0
+CHECK:       Attributes [ (0x800004)
+CHECK:         PureInstructions (0x800000)
+CHECK:         SomeInstructions (0x4)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK:     Section {
+CHECK:       Name: __unwind_info
+CHECK:       Segment: __TEXT
+CHECK32:     Address: 0x1FAC
+CHECK64:     Address: 0x100000FAC
+CHECK:       Size: 0x48
+CHECK:       Offset: 0
+CHECK:       Alignment: 2
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: 0x0
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK32:  Section {
+CHECK32:    Name: __nl_symbol_ptr
+CHECK32:    Segment: __DATA
+CHECK32:    Address: 0x2000
+CHECK32:    Size: 0x4
+CHECK32:    Offset: 0
+CHECK32:    Alignment: 2
+CHECK32:    RelocationOffset: 0x0
+CHECK32:    RelocationCount: 0
+CHECK32:    Type: 0x6
+CHECK32:    Attributes [ (0x0)
+CHECK32:    ]
+CHECK32:    Reserved1: 0x0
+CHECK32:    Reserved2: 0x0
+CHECK32:  }
+CHECK:     Section {
+CHECK:       Name: __data
+CHECK:       Segment: __DATA
+CHECK32:     Address: 0x2004
+CHECK64:     Address: 0x100001000
+CHECK:       Size: 0x4
+CHECK:       Offset: 0
+CHECK:       Alignment: 2
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: 0x0
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK:     Section {
+CHECK:       Name: __common
+CHECK:       Segment: __DATA
+CHECK32:     Address: 0x2008
+CHECK64:     Address: 0x100001004
+CHECK:       Size: 0x4
+CHECK:       Offset: 0
+CHECK:       Alignment: 2
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: LocReloc (0x1)
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK:     Section {
+CHECK:       Name: __bss
+CHECK:       Segment: __DATA
+CHECK32:     Address: 0x200C
+CHECK64:     Address: 0x100001008
+CHECK:       Size: 0x4
+CHECK:       Offset: 0
+CHECK:       Alignment: 2
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: LocReloc (0x1)
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK64:   Section {
+CHECK64:     Name: __debug_line
+CHECK64:     Segment: __DWARF
+CHECK64:     Address: 0x100003000
+CHECK64:     Size: 0xEA
+CHECK64:     Offset: 8192
+CHECK64:     Alignment: 0
+CHECK64:     RelocationOffset: 0x0
+CHECK64:     RelocationCount: 0
+CHECK64:     Type: 0x0
+CHECK64:     Attributes [ (0x0)
+CHECK64:     ]
+CHECK64:     Reserved1: 0x0
+CHECK64:     Reserved2: 0x0
+CHECK64:   }
+CHECK64:   Section {
+CHECK64:     Name: __debug_pubnames
+CHECK64:     Segment: __DWARF
+CHECK64:     Address: 0x1000030EA
+CHECK64:     Size: 0x7F
+CHECK64:     Offset: 8426
+CHECK64:     Alignment: 0
+CHECK64:     RelocationOffset: 0x0
+CHECK64:     RelocationCount: 0
+CHECK64:     Type: 0x0
+CHECK64:     Attributes [ (0x0)
+CHECK64:     ]
+CHECK64:     Reserved1: 0x0
+CHECK64:     Reserved2: 0x0
+CHECK64:   }
+CHECK64:   Section {
+CHECK64:     Name: __debug_pubtypes
+CHECK64:     Segment: __DWARF
+CHECK64:     Address: 0x100003169
+CHECK64:     Size: 0x57
+CHECK64:     Offset: 8553
+CHECK64:     Alignment: 0
+CHECK64:     RelocationOffset: 0x0
+CHECK64:     RelocationCount: 0
+CHECK64:     Type: 0x0
+CHECK64:     Attributes [ (0x0)
+CHECK64:     ]
+CHECK64:     Reserved1: 0x0
+CHECK64:     Reserved2: 0x0
+CHECK64:   }
+CHECK64:   Section {
+CHECK64:     Name: __debug_aranges
+CHECK64:     Segment: __DWARF
+CHECK64:     Address: 0x1000031C0
+CHECK64:     Size: 0xB0
+CHECK64:     Offset: 8640
+CHECK64:     Alignment: 0
+CHECK64:     RelocationOffset: 0x0
+CHECK64:     RelocationCount: 0
+CHECK64:     Type: 0x0
+CHECK64:     Attributes [ (0x0)
+CHECK64:     ]
+CHECK64:     Reserved1: 0x0
+CHECK64:     Reserved2: 0x0
+CHECK64:   }
+CHECK64:   Section {
+CHECK64:     Name: __debug_info
+CHECK64:     Segment: __DWARF
+CHECK64:     Address: 0x100003270
+CHECK64:     Size: 0x1BC
+CHECK64:     Offset: 8816
+CHECK64:     Alignment: 0
+CHECK64:     RelocationOffset: 0x0
+CHECK64:     RelocationCount: 0
+CHECK64:     Type: 0x0
+CHECK64:     Attributes [ (0x0)
+CHECK64:     ]
+CHECK64:     Reserved1: 0x0
+CHECK64:     Reserved2: 0x0
+CHECK64:   }
+CHECK:     Section {
+CHECK:       Name: __debug_abbrev
+CHECK:       Segment: __DWARF
+CHECK32:     Address: 0x4000
+CHECK32:     Size: 0x1
+CHECK32:     Offset: 8192
+CHECK64:     Address: 0x10000342C
+CHECK64:     Size: 0x8F
+CHECK64:     Offset: 9260
+CHECK:       Alignment: 0
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: 0x0
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK:     Section {
+CHECK:       Name: __debug_str
+CHECK:       Segment: __DWARF
+CHECK32:     Address: 0x4001
+CHECK32:     Size: 0x1
+CHECK32:     Offset: 8193
+CHECK64:     Address: 0x1000034BB
+CHECK64:     Size: 0x9F
+CHECK64:     Offset: 9403
+CHECK:       Alignment: 0
+CHECK:       RelocationOffset: 0x0
+CHECK:       RelocationCount: 0
+CHECK:       Type: 0x0
+CHECK:       Attributes [ (0x0)
+CHECK:       ]
+CHECK:       Reserved1: 0x0
+CHECK:       Reserved2: 0x0
+CHECK:     }
+CHECK:   ]
+CHECK:   Symbols [
+CHECK:     Symbol {
+CHECK:       Name: _inc (2)
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x1F20
+CHECK64:     Value: 0x100000F20
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _inc (2)
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x1F90
+CHECK64:     Value: 0x100000F90
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _baz (7)
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __data
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x2004
+CHECK64:     Value: 0x100001000
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _private_int (12)
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __bss
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x200C
+CHECK64:     Value: 0x100001008
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: __mh_execute_header (25)
+CHECK:       Extern
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x10)
+CHECK:         ReferencedDynamically (0x10)
+CHECK:       ]
+CHECK32:     Value: 0x1000
+CHECK64:     Value: 0x100000000
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _bar (45)
+CHECK:       Extern
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x1F40
+CHECK64:     Value: 0x100000F40
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _foo (50)
+CHECK:       Extern
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x1EC0
+CHECK64:     Value: 0x100000ED0
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _main (55)
+CHECK:       Extern
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __text
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x1E90
+CHECK64:     Value: 0x100000EA0
+CHECK:     }
+CHECK:     Symbol {
+CHECK:       Name: _val (61)
+CHECK:       Extern
+CHECK:       Type: Section (0xE)
+CHECK:       Section: __common
+CHECK:       RefType: UndefinedNonLazy (0x0)
+CHECK:       Flags [ (0x0)
+CHECK:       ]
+CHECK32:     Value: 0x2008
+CHECK64:     Value: 0x100001004
+CHECK:     }
+CHECK:   ]
+