[lld-macho] Update -adhoc_codesign default

[keith]

Summary

With newer versions of ld64 it generates an adhoc signature by default
for all arm64 simulator targets. This default is especially important
for unit test targets that rarely have custom codesigning requirements
but otherwise won't run on arm64 macs.

[thakis]

LG

Does newer ld64 adhoc sign catalyst binaries too? Or not yet? (See https://github.com/nico/hack/blob/main/notes/catalyst.md for how to check)

[keith]

Yes it does, and it looks like we get that today with lld because of platform == PLATFORM_MACOS

lld/MachO/Driver.cpp

PlatformType macho::removeSimulator(PlatformType platform) {
   }
 }
 
 static bool supportsNoPie() {
   return !(config->arch() == AK_arm64 || config->arch() == AK_arm64e ||
            config->arch() == AK_arm64_32);
 }
 
+static bool shouldAdhocSignByDefault(Architecture arch, PlatformType platform) {
+  if (arch != AK_arm64 && arch != AK_arm64e)
+    return false;
+
+  return platform == PLATFORM_MACOS || platform == PLATFORM_IOSSIMULATOR ||
+         platform == PLATFORM_TVOSSIMULATOR ||
+         platform == PLATFORM_WATCHOSSIMULATOR;
+}
+
 static bool dataConstDefault(const InputArgList &args) {
   static const std::array<std::pair<PlatformType, VersionTuple>, 5> minVersion =
       {{{PLATFORM_MACOS, VersionTuple(10, 15)},
         {PLATFORM_IOS, VersionTuple(13, 0)},
         {PLATFORM_TVOS, VersionTuple(13, 0)},
         {PLATFORM_WATCHOS, VersionTuple(6, 0)},
         {PLATFORM_BRIDGEOS, VersionTuple(4, 0)}}};
   PlatformType platform = removeSimulator(config->platformInfo.target.Platform);
for (const Arg *arg : args.filtered(OPT_why_live))
     config->whyLive.insert(arg->getValue());
   if (!config->whyLive.empty() && !config->deadStrip)
     warn("-why_live has no effect without -dead_strip, ignoring");
 
   config->saveTemps = args.hasArg(OPT_save_temps);
 
   config->adhocCodesign = args.hasFlag(
       OPT_adhoc_codesign, OPT_no_adhoc_codesign,
-      (config->arch() == AK_arm64 || config->arch() == AK_arm64e) &&
-          config->platform() == PLATFORM_MACOS);
+      shouldAdhocSignByDefault(config->arch(), config->platform()));
 
   if (args.hasArg(OPT_v)) {
     message(getLLDVersion(), lld::errs());
     message(StringRef("Library search paths:") +
                 (config->librarySearchPaths.empty()
                      ? ""
                      : "\n\t" + join(config->librarySearchPaths, "\n\t")),
             lld::errs());

lld/test/MachO/adhoc-codesign.s

 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=NO-ADHOC %s
 # RUN: %lld          -arch arm64 -dylib   -no_adhoc_codesign -o %t/out %t/foo-arm64-macos.o
 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=NO-ADHOC %s
 # RUN: %lld          -arch arm64 -bundle  -no_adhoc_codesign -o %t/out %t/foo-arm64-macos.o
 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=NO-ADHOC %s
 
 
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -execute -o %t/out %t/main-arm64-sim.o -syslibroot %S/Inputs/iPhoneSimulator.sdk -lSystem
-# RUN: llvm-objdump --macho --all-headers %t/out | FileCheck --check-prefix=NO-ADHOC %s
+# RUN: llvm-objdump --macho --all-headers %t/out | FileCheck --check-prefix=ADHOC %s
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -dylib   -o %t/out %t/foo-arm64-sim.o
-# RUN: llvm-objdump --macho --all-headers  %t/out| FileCheck --check-prefix=NO-ADHOC %s
+# RUN: llvm-objdump --macho --all-headers  %t/out| FileCheck --check-prefix=ADHOC %s
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -bundle  -o %t/out %t/foo-arm64-sim.o
-# RUN: llvm-objdump --macho --all-headers  %t/out| FileCheck --check-prefix=NO-ADHOC %s
+# RUN: llvm-objdump --macho --all-headers  %t/out| FileCheck --check-prefix=ADHOC %s
 
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -execute -adhoc_codesign -o %t/out %t/main-arm64-sim.o -syslibroot %S/Inputs/iPhoneSimulator.sdk -lSystem
 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=ADHOC %s
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -dylib   -adhoc_codesign -o %t/out %t/foo-arm64-sim.o
 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=ADHOC %s
 # RUN: %no-arg-lld -arch arm64 -platform_version ios-simulator 14.0 15.0 -bundle  -adhoc_codesign -o %t/out %t/foo-arm64-sim.o
 # RUN: llvm-objdump --macho --all-headers %t/out| FileCheck --check-prefix=ADHOC %s