nuudlman/llvm: llvm/test/CodeGen/AMDGPU/select-undef.ll

; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck -check-prefix=GCN %s

; GCN-LABEL: {{^}}select_undef_lhs:
; GCN: s_waitcnt
; GCN-NOT: v_cmp
; GCN-NOT: v_cndmask
; GCN-NEXT: s_setpc_b64
define float @select_undef_lhs(float %val, i1 %cond) {
  %undef = call float @llvm.amdgcn.rcp.f32(float undef)
  %sel = select i1 %cond, float %undef, float %val
  ret float %sel
}

; GCN-LABEL: {{^}}select_undef_rhs:
; GCN: s_waitcnt
; GCN-NOT: v_cmp
; GCN-NOT: v_cndmask
; GCN-NEXT: s_setpc_b64
define float @select_undef_rhs(float %val, i1 %cond) {
  %undef = call float @llvm.amdgcn.rcp.f32(float undef)
  %sel = select i1 %cond, float %val, float %undef
  ret float %sel
}

; GCN-LABEL: {{^}}select_undef_n1:
; GCN: v_mov_b32_e32 [[RES:v[0-9]+]], 1.0
; GCN: store_dword {{[^,]+}}, [[RES]]
define void @select_undef_n1(float addrspace(1)* %a, i32 %c) {
  %cc = icmp eq i32 %c, 0
  %sel = select i1 %cc, float 1.000000e+00, float undef
  store float %sel, float addrspace(1)* %a
  ret void
}

; GCN-LABEL: {{^}}select_undef_n2:
; GCN: v_mov_b32_e32 [[RES:v[0-9]+]], 1.0
; GCN: store_dword {{[^,]+}}, [[RES]]
define void @select_undef_n2(float addrspace(1)* %a, i32 %c) {
  %cc = icmp eq i32 %c, 0
  %sel = select i1 %cc, float undef, float 1.000000e+00
  store float %sel, float addrspace(1)* %a
  ret void
}

declare float @llvm.amdgcn.rcp.f32(float)


; Make sure the vector undef isn't lowered into 0s.
; GCN-LABEL: {{^}}undef_v6f32:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v6f32(<6 x float> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <6 x float> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <6 x float>, <6 x float> addrspace(3)* undef
  %add = fadd <6 x float> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <6 x float> %add, <6 x float> addrspace(3)* undef
  ret void
}

; GCN-LABEL: {{^}}undef_v6i32:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v6i32(<6 x i32> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <6 x i32> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <6 x i32>, <6 x i32> addrspace(3)* undef
  %add = add <6 x i32> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <6 x i32> %add, <6 x i32> addrspace(3)* undef
  ret void
}

; Make sure the vector undef isn't lowered into 0s.
; GCN-LABEL: {{^}}undef_v5f32:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v5f32(<5 x float> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <5 x float> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <5 x float>, <5 x float> addrspace(3)* undef
  %add = fadd <5 x float> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <5 x float> %add, <5 x float> addrspace(3)* undef
  ret void
}

; GCN-LABEL: {{^}}undef_v5i32:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v5i32(<5 x i32> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <5 x i32> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <5 x i32>, <5 x i32> addrspace(3)* undef
  %add = add <5 x i32> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <5 x i32> %add, <5 x i32> addrspace(3)* undef
  ret void
}

; Make sure the vector undef isn't lowered into 0s.
; GCN-LABEL: {{^}}undef_v3f64:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v3f64(<3 x double> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <3 x double> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <3 x double>, <3 x double> addrspace(3)* %ptr
  %add = fadd <3 x double> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <3 x double> %add, <3 x double> addrspace(3)* %ptr
  ret void
}

; GCN-LABEL: {{^}}undef_v3i64:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v3i64(<3 x i64> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <3 x i64> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <3 x i64>, <3 x i64> addrspace(3)* %ptr
  %add = add <3 x i64> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <3 x i64> %add, <3 x i64> addrspace(3)* %ptr
  ret void
}

; Make sure the vector undef isn't lowered into 0s.
; GCN-LABEL: {{^}}undef_v4f16:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v4f16(<4 x half> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <4 x half> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <4 x half>, <4 x half> addrspace(3)* %ptr
  %add = fadd <4 x half> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <4 x half> %add, <4 x half> addrspace(3)* %ptr
  ret void
}

; GCN-LABEL: {{^}}undef_v4i16:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v4i16(<4 x i16> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <4 x i16> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <4 x i16>, <4 x i16> addrspace(3)* %ptr
  %add = add <4 x i16> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <4 x i16> %add, <4 x i16> addrspace(3)* %ptr
  ret void
}

; Make sure the vector undef isn't lowered into 0s.
; GCN-LABEL: {{^}}undef_v2f16:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v2f16(<2 x half> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <2 x half> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <2 x half>, <2 x half> addrspace(3)* %ptr
  %add = fadd <2 x half> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <2 x half> %add, <2 x half> addrspace(3)* %ptr
  ret void
}

; GCN-LABEL: {{^}}undef_v2i16:
; GCN-NOT: v_mov_b32_e32 v{{[0-9]+}}, 0
; GCN-NOT: s_mov_b32 s{{[0-9]+}}, 0
; GCN: s_cbranch_vccnz
define amdgpu_kernel void @undef_v2i16(<2 x i16> addrspace(3)* %ptr, i1 %cond) {
entry:
  br label %loop

loop:
  %phi = phi <2 x i16> [ undef, %entry ], [ %add, %loop ]
  %load = load volatile <2 x i16>, <2 x i16> addrspace(3)* %ptr
  %add = add <2 x i16> %load, %phi
  br i1 %cond, label %loop, label %ret

ret:
  store volatile <2 x i16> %add, <2 x i16> addrspace(3)* %ptr
  ret void
}

; We were expanding undef vectors into zero vectors. Optimizations
; would then see we used no elements of the vector, and reform the
; undef vector resulting in a combiner loop.
; GCN-LABEL: {{^}}inf_loop_undef_vector:
; GCN: s_waitcnt
; GCN-NEXT: v_mad_u64_u32
; GCN-NEXT: v_mul_lo_u32
; GCN-NEXT: v_mul_lo_u32
; GCN-NEXT: v_add3_u32
; GCN-NEXT: global_store_dwordx2
define void @inf_loop_undef_vector(<6 x float> %arg, float %arg1, i64 %arg2) {
  %i = insertelement <6 x float> %arg, float %arg1, i64 2
  %i3 = bitcast <6 x float> %i to <3 x i64>
  %i4 = extractelement <3 x i64> %i3, i64 0
  %i5 = extractelement <3 x i64> %i3, i64 1
  %i6 = mul i64 %i5, %arg2
  %i7 = add i64 %i6, %i4
  store volatile i64 %i7, i64 addrspace(1)* undef, align 4
  ret void
}