[lld/mac] Support -data_in_code_info, -function_starts flags

[thakis]

Summary

These are on by default, but there's also an explicit flag for them.

[thakis]

lld/test/MachO/data-in-code.s

7

(I'm adding this because ld needs it, and I often locally replace %lld with ld to verify that the test would pass with ld64 too.)

[gkm]

Bueno!

lld/MachO/Driver.cpp

config->ltoNewPassManager =
                    LLVM_ENABLE_NEW_PASS_MANAGER);
   config->runtimePaths = args::getStrings(args, OPT_rpath);
   config->allLoad = args.hasArg(OPT_all_load);
   config->forceLoadObjC = args.hasArg(OPT_ObjC);
   config->forceLoadSwift = args.hasArg(OPT_force_load_swift_libs);
   config->deadStripDylibs = args.hasArg(OPT_dead_strip_dylibs);
   config->demangle = args.hasArg(OPT_demangle);
   config->implicitDylibs = !args.hasArg(OPT_no_implicit_dylibs);
-  config->emitFunctionStarts = !args.hasArg(OPT_no_function_starts);
+  config->emitFunctionStarts =
+      args.hasFlag(OPT_function_starts, OPT_no_function_starts, true);
   config->emitBitcodeBundle = args.hasArg(OPT_bitcode_bundle);
-  config->emitDataInCodeInfo = !args.hasArg(OPT_no_data_in_code_info);
+  config->emitDataInCodeInfo =
+      args.hasFlag(OPT_data_in_code_info, OPT_no_data_in_code_info, true);
   config->dedupLiterals = args.hasArg(OPT_deduplicate_literals);
 
   // FIXME: Add a commandline flag for this too.
   config->zeroModTime = getenv("ZERO_AR_DATE");
 
   std::array<PlatformKind, 3> encryptablePlatforms{
       PlatformKind::iOS, PlatformKind::watchOS, PlatformKind::tvOS};
   config->emitEncryptionInfo =

lld/MachO/Options.td

def read_only_stubs : Flag<["-"], "read_only_stubs">,
     Flags<[HelpHidden]>,
     Group<grp_rare>;
 def interposable_list : Separate<["-"], "interposable_list">,
     MetaVarName<"<path>">,
     HelpText<"Access global symbols listed in <path> indirectly">,
     Flags<[HelpHidden]>,
     Group<grp_rare>;
 def no_function_starts : Flag<["-"], "no_function_starts">,
-    HelpText<"Do not create a table of function start addresses">,
+    HelpText<"Do not create table of function start addresses">,
     Group<grp_rare>;
 def no_objc_category_merging : Flag<["-"], "no_objc_category_merging">,
     HelpText<"Do not merge Objective-C categories into their classes">,
     Flags<[HelpHidden]>,
     Group<grp_rare>;
 def object_path_lto : Separate<["-"], "object_path_lto">,
     MetaVarName<"<path>">,
     HelpText<"Retain any temporary mach-o file in <path> that would otherwise be deleted during LTO">,
def bitcode_verify : Flag<["-"], "bitcode_verify">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
 def classic_linker : Flag<["-"], "classic_linker">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
 def data_in_code_info : Flag<["-"], "data_in_code_info">,
-    HelpText<"This option is undocumented in ld64">,
-    Flags<[HelpHidden]>,
+    HelpText<"Emit data-in-code information (default)">,
     Group<grp_undocumented>;
 def no_data_in_code_info : Flag<["-"], "no_data_in_code_info">,
     HelpText<"Do not emit data-in-code information">,
     Group<grp_undocumented>;
 def debug_snapshot : Flag<["-"], "debug_snapshot">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
def force_symbols_weak_list : Flag<["-"], "force_symbols_weak_list">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
 def force_symbol_weak : Flag<["-"], "force_symbol_weak">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
 def function_starts : Flag<["-"], "function_starts">,
-    HelpText<"This option is undocumented in ld64">,
-    Flags<[HelpHidden]>,
+    HelpText<"Create table of function start addresses (default)">,
     Group<grp_undocumented>;
 def i : Flag<["-"], "i">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,
     Group<grp_undocumented>;
 def ignore_auto_link : Flag<["-"], "ignore_auto_link">,
     HelpText<"This option is undocumented in ld64">,
     Flags<[HelpHidden]>,

lld/test/MachO/data-in-code.s

 # REQUIRES: x86
 
 # RUN: rm -rf %t; split-file %s %t
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/foo.s -o %t/foo.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/bar.s -o %t/bar.o
-# RUN: %lld %t/foo.o %t/bar.o -o %t/main.exe
+# RUN: %lld -lSystem %t/foo.o %t/bar.o -o %t/main.exe
 # RUN: llvm-otool -l %t/main.exe > %t/objdump
 # RUN: llvm-objdump --macho --data-in-code %t/main.exe >> %t/objdump
 # RUN: FileCheck %s < %t/objdump
 
 # CHECK-LABEL:  sectname __text
 # CHECK-NEXT:   segname __TEXT
 # CHECK-NEXT:   addr
 # CHECK-NEXT:   size
 # CHECK-NEXT:   offset [[#%,TEXT:]]
 
 # CHECK-LABEL:  cmd LC_DATA_IN_CODE
 # CHECK-NEXT:   cmdsize 16
 # CHECK-NEXT:   dataoff
 # CHECK-NEXT:   datasize 16
 
 # CHECK-LABEL:  Data in code table (2 entries)
 # CHECK-NEXT:   offset length kind
 # CHECK-NEXT:   [[#%x,TEXT + 28]] 24 JUMP_TABLE32
 # CHECK-NEXT:   [[#%x,TEXT + 68]] 12 JUMP_TABLE32
 
-# RUN: %lld %t/foo.o %t/bar.o -no_data_in_code_info -o %t/main.exe
+# RUN: %lld -lSystem %t/foo.o %t/bar.o -no_data_in_code_info -o %t/main.exe
 # RUN: llvm-otool -l %t/main.exe | FileCheck --check-prefix=OMIT %s
 
 # OMIT-NOT: LC_DATA_IN_CODE
 
+# RUN: %lld -lSystem %t/foo.o %t/bar.o -no_data_in_code_info -data_in_code_info -o %t/main.exe
+# RUN: llvm-otool -l %t/main.exe > %t/objdump
+# RUN: llvm-objdump --macho --data-in-code %t/main.exe >> %t/objdump
+# RUN: FileCheck %s < %t/objdump
+
 #--- foo.s
 .text
 .globl _main
 .p2align 4, 0x90
 _main:
 pushq %rbp
 movq  %rsp, %rbp
 subq  $16, %rsp

lld/test/MachO/function-starts.s

 # REQUIRES: x86
 
 # RUN: rm -rf %t; split-file %s %t
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/basic.s -o %t/basic.o
-# RUN: %lld %t/basic.o -o %t/basic
+# RUN: %lld -lSystem %t/basic.o -o %t/basic
 # RUN: llvm-objdump --syms %t/basic > %t/objdump
 # RUN: llvm-objdump --macho --function-starts %t/basic >> %t/objdump
 # RUN: FileCheck %s --check-prefix=BASIC < %t/objdump
 
 # BASIC-LABEL: SYMBOL TABLE:
 # BASIC-NEXT:  [[#%x,MAIN:]] g F __TEXT,__text _main
 # BASIC-NEXT:  [[#%x,F1:]] g F __TEXT,__text _f1
 # BASIC-NEXT:  [[#%x,F2:]] g F __TEXT,__text _f2
 # BASIC-LABEL: basic:
 # BASIC:       [[#F1]]
 # BASIC:       [[#F2]]
 # BASIC:       [[#MAIN]]
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/alias.s -o %t/alias.o
-# RUN: %lld %t/alias.o -o %t/alias
+# RUN: %lld -lSystem %t/alias.o -o %t/alias
 # RUN: llvm-objdump --syms  %t/alias > %t/objdump
 # RUN: llvm-objdump --macho --function-starts %t/alias >> %t/objdump
 # RUN: FileCheck %s --check-prefix=ALIAS < %t/objdump
 
 # ALIAS-LABEL: SYMBOL TABLE:
 # ALIAS-NEXT:  [[#%x,F2:]] l F __TEXT,__text _f2
 # ALIAS-NEXT:  [[#%x,MAIN:]] g F __TEXT,__text _main
 # ALIAS-NEXT:  [[#%x,F1:]] g F __TEXT,__text _f1
 # ALIAS-LABEL: alias:
 # ALIAS:       [[#F1]]
 # ALIAS:       [[#MAIN]]
 
 # RUN: %lld %t/basic.o -no_function_starts -o %t/basic-no-function-starts
 # RUN: llvm-objdump --macho --function-starts %t/basic-no-function-starts | FileCheck %s --check-prefix=NO-FUNCTION-STARTS
 # NO-FUNCTION-STARTS: basic-no-function-starts:
 # NO-FUNCTION-STARTS-EMPTY:
 
+# RUN: %lld -lSystem %t/basic.o -no_function_starts -function_starts -o %t/basic-explicit
+# RUN: llvm-objdump --syms %t/basic > %t/objdump
+# RUN: llvm-objdump --macho --function-starts %t/basic >> %t/objdump
+# RUN: FileCheck %s --check-prefix=BASIC < %t/objdump
+
 #--- basic.s
 .section  __TEXT,__text,regular,pure_instructions
 .globl  _f1
 .globl  _f2
 .globl  _main
 _f1:
   retq
 _f2: