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