mac doesn't fail yet

Author: arsenm

llvm/test/MC/AMDGPU/unknown-target-cpu.s

@@ -1,12 +1,14 @@
-// RUN: not llvm-mc -triple=amdgcn -show-encoding %s | FileCheck %s
-// RUN: not llvm-mc -triple=amdgcn -show-encoding -filetype=null %s 2>&1 | FileCheck --implicit-check-not=error -check-prefix=ERR %s
+// RUN: llvm-mc -triple=amdgcn -show-encoding < %s | FileCheck %s
+// RUN: llvm-mc -triple=amdgcn -mcpu=tahiti -show-encoding < %s | FileCheck %s
 
 // CHECK: v_cmp_lt_f32_e32 vcc, s2, v4            ; encoding: [0x02,0x08,0x02,0x7c]
 v_cmp_lt_f32 vcc, s2, v4
 
 // CHECK: v_cndmask_b32_e32 v1, v2, v3, vcc       ; encoding: [0x02,0x07,0x02,0x00]
 v_cndmask_b32 v1, v2, v3, vcc
 
-// ERR: [[@LINE+1]]:1: error: instruction not supported on this GPU
+// CHECK: v_mac_legacy_f32_e64 v1, v3, s5         ; encoding: [0x01,0x00,0x0c,0xd2,0x03,0x0b,0x00,0x00]
 v_mac_legacy_f32 v1, v3, s5
 
+// CHECK: v_lshr_b32_e32 v0, v1, v2               ; encoding: [0x01,0x05,0x00,0x2a]
+v_lshr_b32 v0, v1, v2