[NFC][X86] Add MC tests for all untested VIA PadLock instructions

We currently only test the encoding of xstore but none of the other
instructions, which should all have their implicit REP prefix be
verified as working.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D112354

Author: jrtc27

llvm/test/MC/X86/padlock.s

@@ -3,3 +3,27 @@
 	xstore
 // CHECK: xstore
 // CHECK: encoding: [0xf3,0x0f,0xa7,0xc0]
+	xcryptecb
+// CHECK: xcryptecb
+// CHECK: encoding: [0xf3,0x0f,0xa7,0xc8]
+	xcryptcbc
+// CHECK: xcryptcbc
+// CHECK: encoding: [0xf3,0x0f,0xa7,0xd0]
+	xcryptctr
+// CHECK: xcryptctr
+// CHECK: encoding: [0xf3,0x0f,0xa7,0xd8]
+	xcryptcfb
+// CHECK: xcryptcfb
+// CHECK: encoding: [0xf3,0x0f,0xa7,0xe0]
+	xcryptofb
+// CHECK: xcryptofb
+// CHECK: encoding: [0xf3,0x0f,0xa7,0xe8]
+	xsha1
+// CHECK: xsha1
+// CHECK: encoding: [0xf3,0x0f,0xa6,0xc8]
+	xsha256
+// CHECK: xsha256
+// CHECK: encoding: [0xf3,0x0f,0xa6,0xd0]
+	montmul
+// CHECK: montmul
+// CHECK: encoding: [0xf3,0x0f,0xa6,0xc0]