llvm/llvm/test/MC/AMDGPU/gfx10_unsupported_e64.s

// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1010 -mattr=+wavefrontsize32 %s 2>&1 | FileCheck --implicit-check-not=error: %s
// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1010 -mattr=+wavefrontsize64 %s 2>&1 | FileCheck --implicit-check-not=error: %s
// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1013 -mattr=+wavefrontsize32 %s 2>&1 | FileCheck --implicit-check-not=error: %s

v_swap_b32_e64 v1, v2
// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: e64 variant of this instruction is not supported