diff --git a/scripts/checkstack.pl b/scripts/checkstack.pl
index c05d586..899b423 100755
--- a/scripts/checkstack.pl
+++ b/scripts/checkstack.pl
@@ -52,14 +52,12 @@
 		#8000008a:       20 1d           sub sp,4
 		#80000ca8:       fa cd 05 b0     sub sp,sp,1456
 		$re = qr/^.*sub.*sp.*,([0-9]{1,8})/o;
-	} elsif ($arch =~ /^i[3456]86$/) {
+	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
 		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
-		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%esp$/o;
-		$dre = qr/^.*[as][du][db]    (%.*),\%esp$/o;
-	} elsif ($arch eq 'x86_64') {
-		#    2f60:	48 81 ec e8 05 00 00 	sub    $0x5e8,%rsp
-		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%rsp$/o;
-		$dre = qr/^.*[as][du][db]    (\%.*),\%rsp$/o;
+		# or
+		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
+		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
+		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
 	} elsif ($arch eq 'ia64') {
 		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
 		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;