1; RUN: llc -march=amdgcn -mcpu=SI -o - %s | FileCheck %s 2; Don't crash when the use of an undefined value is only detected by the 3; register coalescer because it is hidden with subregister insert/extract. 4target triple="amdgcn--" 5 6; CHECK-LABEL: foobar: 7; CHECK: s_load_dword s2, s[0:1], 0x9 8; CHECK-NEXT: s_load_dwordx2 s[4:5], s[0:1], 0xb 9; CHECK-NEXT: s_waitcnt lgkmcnt(0) 10; CHECK: v_mbcnt_lo_u32_b32_e64 11; CHECK-NEXT: v_cmp_eq_i32_e32 vcc, 0, v0 12; CHECK-NEXT: s_and_saveexec_b64 s[2:3], vcc 13; CHECK-NEXT: s_xor_b64 s[2:3], exec, s[2:3] 14; BB0_1: 15; CHECK: s_load_dword s0, s[0:1], 0xa 16; CHECK-NEXT: s_waitcnt lgkmcnt(0) 17; BB0_2: 18; CHECK: s_or_b64 exec, exec, s[2:3] 19; CHECK-NEXT: s_mov_b32 s7, 0xf000 20; CHECK-NEXT: s_mov_b32 s6, -1 21; CHECK-NEXT: buffer_store_dword v1, off, s[4:7], 0 22; CHECK-NEXT: s_endpgm 23define void @foobar(float %a0, float %a1, float addrspace(1)* %out) nounwind { 24entry: 25 %v0 = insertelement <4 x float> undef, float %a0, i32 0 26 %tid = call i32 @llvm.amdgcn.mbcnt.lo(i32 -1, i32 0) #0 27 %cnd = icmp eq i32 %tid, 0 28 br i1 %cnd, label %ift, label %ife 29 30ift: 31 %v1 = insertelement <4 x float> undef, float %a1, i32 0 32 br label %ife 33 34ife: 35 %val = phi <4 x float> [ %v1, %ift ], [ %v0, %entry ] 36 %v2 = extractelement <4 x float> %val, i32 1 37 store float %v2, float addrspace(1)* %out, align 4 38 ret void 39} 40 41declare i32 @llvm.amdgcn.mbcnt.lo(i32, i32) #0 42 43attributes #0 = { nounwind readnone } 44