Add Undefined Behavior sanitizer to Swift Driver (swiftlang#18553)

This change allows the swift driver to link the ubsan runtime if
`-sanitize=undefined` is specified.
This is useful for sanitizing linked Objective-C code.

Author: rahul-malik

include/swift/Basic/Sanitizers.h

@@ -19,7 +19,8 @@ namespace swift {
 enum class SanitizerKind : unsigned {
   Address = 1 << 1,
   Thread = 1 << 2,
-  Fuzzer = 1 << 3
+  Fuzzer = 1 << 3,
+  Undefined = 1 << 4
 };
 
 } // end namespace swift

lib/Driver/DarwinToolChains.cpp

@@ -360,6 +360,9 @@ toolchains::Darwin::constructInvocation(const LinkJobAction &job,
   if (context.OI.SelectedSanitizers & SanitizerKind::Thread)
     addLinkSanitizerLibArgsForDarwin(context.Args, Arguments, "tsan", *this);
 
+  if (context.OI.SelectedSanitizers & SanitizerKind::Undefined)
+    addLinkSanitizerLibArgsForDarwin(context.Args, Arguments, "ubsan", *this);
+
   // Only link in libFuzzer for executables.
   if (job.getKind() == LinkKind::Executable &&
       (context.OI.SelectedSanitizers & SanitizerKind::Fuzzer))

lib/Driver/UnixToolChains.cpp

@@ -301,9 +301,13 @@ toolchains::GenericUnix::constructInvocation(const LinkJobAction &job,
       if (context.OI.SelectedSanitizers & SanitizerKind::Thread)
         addLinkSanitizerLibArgsForLinux(context.Args, Arguments, "tsan", *this);
 
+      if (context.OI.SelectedSanitizers & SanitizerKind::Undefined)
+        addLinkSanitizerLibArgsForLinux(context.Args, Arguments, "ubsan", *this);
+
       if (context.OI.SelectedSanitizers & SanitizerKind::Fuzzer)
         addLinkRuntimeLib(context.Args, Arguments,
                           sanitizerRuntimeLibName("fuzzer"));
+
     }
   }
 

lib/Driver/WindowsToolChains.cpp

@@ -147,6 +147,10 @@ toolchains::Windows::constructInvocation(const LinkJobAction &job,
     if (context.OI.SelectedSanitizers & SanitizerKind::Address)
       addLinkRuntimeLib(context.Args, Arguments,
                         sanitizerRuntimeLibName("asan"));
+
+    if (context.OI.SelectedSanitizers & SanitizerKind::Undefined)
+      addLinkRuntimeLib(context.Args, Arguments,
+                        sanitizerRuntimeLibName("ubsan"));
   }
 
   if (context.Args.hasArg(options::OPT_profile_generate)) {

lib/Option/SanitizerOptions.cpp

@@ -37,6 +37,8 @@ static StringRef toStringRef(const SanitizerKind kind) {
     return "thread";
   case SanitizerKind::Fuzzer:
     return "fuzzer";
+  case SanitizerKind::Undefined:
+    return "undefined";
   }
   llvm_unreachable("Unsupported sanitizer");
 }
@@ -49,6 +51,8 @@ static const char* toFileName(const SanitizerKind kind) {
     return "tsan";
   case SanitizerKind::Fuzzer:
     return "fuzzer";
+  case SanitizerKind::Undefined:
+    return "ubsan";
   }
   llvm_unreachable("Unsupported sanitizer");
 }
@@ -134,6 +138,7 @@ OptionSet<SanitizerKind> swift::parseSanitizerArgValues(
         .Case("address", SanitizerKind::Address)
         .Case("thread", SanitizerKind::Thread)
         .Case("fuzzer", SanitizerKind::Fuzzer)
+        .Case("undefined", SanitizerKind::Undefined)
         .Default(None);
     bool isShared = kind && *kind != SanitizerKind::Fuzzer;
     if (!kind) {