Use the ProfileStubber utility

This change ensures that the unityjit and unityaot profiles match the
.NET 4.7.1 API by using the profile stubber to modify the IL code in the
class library assemblies.

Author: joshpeterson

external/buildscripts/build.pl

@@ -180,6 +180,8 @@
 # abs_path ends up returning an empty string
 $externalBuildDeps = abs_path($externalBuildDeps) if (-d $externalBuildDeps);
 
+my $extraBuildTools = "$monoroot/../../mono-build-tools-extra/build";
+
 my $existingExternalMonoRoot = "$externalBuildDeps/MonoBleedingEdge";
 my $existingExternalMono = "";
 my $existingExternalMonoBinDir = "";
@@ -269,6 +271,23 @@
 		push @configureparams, "--with-monotouch=no";
 	}
 
+	if (!(-d "$extraBuildTools"))
+	{
+		# Check out on the fly
+		print(">>> Checking out mono build tools extra to : $extraBuildTools\n");
+		my $repo = '[email protected]:vm/mono-build-tools-extra.git';
+		print(">>> Cloning $repo at $extraBuildTools\n");
+		my $checkoutResult = system("git", "clone", "--recurse-submodules", $repo, "$extraBuildTools");
+
+		if ($checkoutResult ne 0)
+		{
+			die("Failed to checkout mono build tools extra\n");
+		}
+
+		# Only clean up if the dir exists.   Otherwise abs_path will return empty string
+		$extraBuildTools = abs_path($extraBuildTools) if (-d $extraBuildTools);
+	}
+
 	if ($existingMonoRootPath eq "")
 	{
 		print(">>> No existing mono supplied.  Checking for external...\n");
@@ -1415,6 +1434,13 @@
 		}
 
 		chdir("$monoroot");
+
+		my $stubResult = system("perl", "$buildscriptsdir/stub_classlibs.pl");
+
+		if ($stubResult ne 0)
+		{
+			die("Failed to run the profile stubber\n");
+		}
 	}
 }
 else

external/buildscripts/stub_classlibs.pl

@@ -0,0 +1,52 @@
+use Cwd;
+use Cwd 'abs_path';
+use File::Basename;
+use File::Path;
+
+if($^O ne "darwin")
+{
+	print ">>> The ProfileStubber is only built and run in the class library build on macOS\n";
+	exit
+}
+
+my $monoroot = File::Spec->rel2abs(dirname(__FILE__) . "/../..");
+my $monoroot = abs_path($monoroot);
+my $extraBuildTools = "$monoroot/../../mono-build-tools-extra/build";
+
+print ">>> Building the ProfileStubber utility\n";
+
+my $result = system("xbuild",
+					"$extraBuildTools/mono-build-tools-extra.sln",
+					"/p:Configuration=Release");
+
+if ($result ne 0)
+{
+	die("Failed to build ProfileStubber utility\n");
+}
+
+my $profileRoot = "tmp/lib/mono";
+my $referenceProfile = "$profileRoot/4.7.1-api";
+
+print ">>> Modifying the unityjit profile to match the .NET 4.7.1 API\n";
+
+$result = system("mono",
+					"$extraBuildTools/build/ProfileStubber.exe",
+					"--reference-profile=$referenceProfile",
+					"--stub-profile=$profileRoot/unityjit");
+
+if ($result ne 0)
+{
+	die("Failed to stub the unityjit profile\n");
+}
+
+print ">>> Modifying the unityaot profile to match the .NET 4.7.1 API\n";
+
+$result = system("mono",
+					"$extraBuildTools/build/ProfileStubber.exe",
+					"--reference-profile=$referenceProfile",
+					"--stub-profile=$profileRoot/unityaot");
+
+if ($result ne 0)
+{
+	die("Failed to stub the unityaot profile\n");
+}