[macho] Minor install_name fixes

Summary:
Fix the binary file reader to properly read dyld version info.
Update the install_name test case to properly test the binary reader. We can't use '-print_atoms' as the output format is 'native' yaml and it does not contains the dyld current and compatibility versions. 

Also change the timestamp value of LD_ID_DYLD to match the one generated by ld64.
The dynamic linker (dyld) used to expects different values for timestamp in LD_ID_DYLD and LD_LOAD_DYLD for prebound images. While prebinding is deprecated, we should probably keep it safe and match ld64. 

Reviewers: kledzik

Subscribers: llvm-commits

Projects: #lld

Differential Revision: http://reviews.llvm.org/D6736

llvm-svn: 224681

3 files changed, 29 insertions, 14 deletions

diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
index ef8ad1d3325..84bf400558d 100644
--- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
@@ -437,6 +437,8 @@ readBinary(std::unique_ptr<MemoryBuffer> &mb,
     case LC_ID_DYLIB: {
       const dylib_command *dl = reinterpret_cast<const dylib_command*>(lc);
       f->installName = lc + read32(&dl->dylib.name, isBig);
+      f->currentVersion = read32(&dl->dylib.current_version, isBig);
+      f->compatVersion = read32(&dl->dylib.compatibility_version, isBig);
       }
       break;
     case LC_DATA_IN_CODE: {
diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp
index a3542c4fc50..be7acf9d4d6 100644
--- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp
@@ -741,7 +741,8 @@ std::error_code MachOFileLayout::writeLoadCommands() {
       dc->cmd                         = LC_ID_DYLIB;
       dc->cmdsize                     = size;
       dc->dylib.name                  = sizeof(dylib_command); // offset
-      dc->dylib.timestamp             = 2;
+      // needs to be some constant value different than the one in LC_LOAD_DYLIB
+      dc->dylib.timestamp             = 1;
       dc->dylib.current_version       = _file.currentVersion;
       dc->dylib.compatibility_version = _file.compatVersion;
       if (_swap)
@@ -841,6 +842,7 @@ std::error_code MachOFileLayout::writeLoadCommands() {
       dc->cmd                         = dep.kind;
       dc->cmdsize                     = size;
       dc->dylib.name                  = sizeof(dylib_command); // offset
+      // needs to be some constant value different than the one in LC_ID_DYLIB
       dc->dylib.timestamp             = 2;
       dc->dylib.current_version       = dep.currentVersion;
       dc->dylib.compatibility_version = dep.compatVersion;
diff --git a/lld/test/mach-o/dylib-install-names.yaml b/lld/test/mach-o/dylib-install-names.yaml
index a79581c0e26..845085be42a 100644
--- a/lld/test/mach-o/dylib-install-names.yaml
+++ b/lld/test/mach-o/dylib-install-names.yaml
@@ -2,24 +2,25 @@
 # RUN: lld -flavor darwin -arch x86_64 -install_name libwibble.dylib -dylib \
 # RUN:     -compatibility_version 2.0 -current_version 5.3 \
 # RUN:     %p/Inputs/libSystem.yaml %s -o %t.dylib
-# RUN: macho-dump %t.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
+# RUN: llvm-objdump -private-headers %t.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
 
 # Check we read LC_ID_DYLIB correctly:
 # RUN: lld -flavor darwin -arch x86_64 %p/Inputs/use-dylib-install-names.yaml \
-# RUN:      %t.dylib -r -print_atoms | FileCheck %s --check-prefix=CHECK-BINARY-READ
+# RUN:      %p/Inputs/libSystem.yaml %t.dylib -dylib -o %t2.dylib
+# RUN: llvm-objdump -private-headers %t2.dylib | FileCheck %s --check-prefix=CHECK-BINARY-READ
 
 # Check we default the install-name to the output file:
 # RUN: lld -flavor darwin -arch x86_64 -dylib %s -o libwibble.dylib \
 # RUN:     -compatibility_version 2.0 -current_version 5.3 \
 # RUN:     %p/Inputs/libSystem.yaml
-# RUN: macho-dump libwibble.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
+# RUN: llvm-objdump -private-headers libwibble.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
 # RUN: rm -f libwibble.dylib
 
 # Check -single_module does nothing
 # RUN: lld -flavor darwin -arch x86_64 -dylib %s -install_name libwibble.dylib \
 # RUN:     -compatibility_version 2.0 -current_version 5.3 \
 # RUN:     -single_module -o %t2.dylib %p/Inputs/libSystem.yaml
-# RUN: macho-dump %t2.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
+# RUN: llvm-objdump -private-headers %t2.dylib | FileCheck %s --check-prefix=CHECK-BINARY-WRITE
 
 --- !mach-o
 arch:            x86_64
@@ -51,13 +52,23 @@ global-symbols:
 ...
 
 
-# CHECK-BINARY-WRITE: (('command', 13)
-# CHECK-BINARY-WRITE-NEXT:  ('size', 40)
-# CHECK-BINARY-WRITE-NEXT:  ('install_name', 'libwibble.dylib')
-# CHECK-BINARY-WRITE-NEXT:    ('timestamp,
-# CHECK-BINARY-WRITE-NEXT:    ('cur_version, 328448)
-# CHECK-BINARY-WRITE-NEXT:    ('compat_version, 131072)
+# CHECK-BINARY-WRITE: cmd LC_ID_DYLIB
+# CHECK-BINARY-WRITE-NEXT: cmdsize 40
+# CHECK-BINARY-WRITE-NEXT:  name libwibble.dylib (offset 24)
+# CHECK-BINARY-WRITE-NEXT:  time stamp 1
+# CHECK-BINARY-WRITE-NEXT:  current version 5.3.0
+# CHECK-BINARY-WRITE-NEXT:  compatibility version 2.0.0
 
-# CHECK-BINARY-READ: shared-library-atoms:
-# CHECK-BINARY-READ:     - name:          _myGlobal
-# CHECK-BINARY-READ:       load-name:     libwibble.dylib
+# CHECK-BINARY-READ: cmd LC_LOAD_DYLIB
+# CHECK-BINARY-READ-NEXT: cmdsize 56
+# CHECK-BINARY-READ-NEXT:  name /usr/lib/libSystem.B.dylib (offset 24)
+# CHECK-BINARY-READ-NEXT:  time stamp 2
+# CHECK-BINARY-READ-NEXT:  current version 0.16.0
+# CHECK-BINARY-READ-NEXT:  compatibility version 0.16.0
+
+# CHECK-BINARY-READ: cmd LC_LOAD_DYLIB
+# CHECK-BINARY-READ-NEXT: cmdsize 40
+# CHECK-BINARY-READ-NEXT:  name libwibble.dylib (offset 24)
+# CHECK-BINARY-READ-NEXT:  time stamp 2
+# CHECK-BINARY-READ-NEXT:  current version 5.3.0
+# CHECK-BINARY-READ-NEXT:  compatibility version 2.0.0