[lld-macho] Put DATA_IN_CODE immediately after FUNCTION_STARTS

[int3]

Summary

codesign checks for this.

[thakis]

FYI, strip needs this too. Without this change, the data-in-code change regressed stripping again, with this error:

% strip out/gn/bin/lld
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/strip: fatal error: file not in an order that can be processed (data in code info out of place): /Users/thakis/src/llvm-project/out/gn/bin/lld

lld/MachO/OutputSegment.cpp

default:
       return StringSwitch<int>(osec->name)
           .Case(section_names::got, -3)
           .Case(section_names::lazySymbolPtr, -2)
           .Case(section_names::const_, -1)
           .Default(osec->inputOrder);
     }
   } else if (segname == segment_names::linkEdit) {
     return StringSwitch<int>(osec->name)
-        .Case(section_names::rebase, -9)
-        .Case(section_names::binding, -8)
-        .Case(section_names::weakBinding, -7)
-        .Case(section_names::lazyBinding, -6)
-        .Case(section_names::export_, -5)
-        .Case(section_names::functionStarts, -4)
+        .Case(section_names::rebase, -10)
+        .Case(section_names::binding, -9)
+        .Case(section_names::weakBinding, -8)
+        .Case(section_names::lazyBinding, -7)
+        .Case(section_names::export_, -6)
+        .Case(section_names::functionStarts, -5)
+        .Case(section_names::dataInCode, -4)
         .Case(section_names::symbolTable, -3)
         .Case(section_names::indirectSymbolTable, -2)
         .Case(section_names::stringTable, -1)
         .Case(section_names::codeSignature, std::numeric_limits<int>::max())
         .Default(osec->inputOrder);
   }
   // ZeroFill sections must always be the at the end of their segments,
   // otherwise subsequent sections may get overwritten with zeroes at runtime.

lld/test/MachO/linkedit-contiguity.s

 # REQUIRES: x86
 # RUN: rm -rf %t; split-file %s %t
 
 ## codesign requires that each setion in __LINKEDIT ends where the next one
 ## starts. This test enforces that invariant.
 ## It also checks that the last section in __LINKEDIT covers the last byte of
 ## the segment.
 
-## FIXME: Include LC_DATA_IN_CODE in this test when we add support for it.
-
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/foo.s -o %t/foo.o
 # RUN: %lld %t/foo.o -dylib -o %t/libfoo.dylib
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/test.s -o %t/test.o
 # RUN: %lld -lSystem -pie -adhoc_codesign -o %t/test %t/libfoo.dylib %t/test.o
 
 # RUN: llvm-objdump --macho --all-headers %t/test | FileCheck %s
 

 # CHECK-NEXT: lazy_bind_off [[#LAZY_OFF: WEAK_OFF + WEAK_SIZE]]
 # CHECK-NEXT: lazy_bind_size [[#LAZY_SIZE:]]
 # CHECK-NEXT: export_off [[#EXPORT_OFF: LAZY_OFF + LAZY_SIZE]]
 # CHECK-NEXT: export_size [[#EXPORT_SIZE:]]
 
 # CHECK:      cmd LC_FUNCTION_STARTS
 # CHECK-NEXT: cmdsize
 # CHECK-NEXT: dataoff [[#FUNCSTARTS_OFF: EXPORT_OFF + EXPORT_SIZE]]
+# CHECK-NEXT: datasize [[#FUNCSTARTS_SIZE:]]
+
+# CHECK:      cmd LC_DATA_IN_CODE
+# CHECK-NEXT: cmdsize
+# CHECK-NEXT: dataoff [[#DIC_OFF: FUNCSTARTS_OFF + FUNCSTARTS_SIZE]]
 
 # CHECK:      cmd LC_CODE_SIGNATURE
 # CHECK-NEXT: cmdsize 16
 # CHECK-NEXT: dataoff [[#SIG_OFF:]]
 # CHECK-NEXT: datasize [[#SIG_SIZE: LINKEDIT_OFF + LINKEDIT_SIZE - SIG_OFF]]
 
 #--- foo.s
 .globl _foo, _weak_foo
 .weak_definition _weak_foo
 _foo:
 _weak_foo:
 
 #--- test.s
 .globl _main
 _main:
   callq _foo
   callq _weak_foo
   ret
+
+.p2align 2, 0x90
+.data_region jt32
+.long 0
+.end_data_region