; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 3 ; RUN: llc -global-isel -amdgpu-global-isel-risky-select -mtriple=amdgcn-amd-amdpal -mcpu=gfx1010 < %s | FileCheck -check-prefix=GFX10 %s ; Divergent phis that don't require lowering using lane mask merging ; - divergent phi that has divergent incoming value (this makes it divergent) ; but is reachable through only one path - branch instruction that chooses ; path is uniform ; - divergent phi that is used only inside the loop and has incoming from ; previous iteration. After phi-elimination (rewrite lane mask in phi def with ; lane mask value from previous iteration), phi will hold lane mask valid for ; current iteration which is fine since it is not used outside of the loop. ; And one more that is tricky (is branch divergent or not ?) ; "amdgpu-flat-work-group-size"="1,1" aka single lane execution does not stop ; shader from activating multiple lanes by using some intrinsic (entering wwm ; and using dpp instructions) ; - there are cases with single lane execution where branch instructions are not ; lowered to si_if (or other intrinsic branches) - with intention to use ; uniform branch after instruction selection? ; PhiIncomingAnalysis does not recognize G_BRCOND as divergent branch and does ; not perform lane mask merging define amdgpu_ps void @divergent_i1_phi_uniform_branch(ptr addrspace(1) %out, i32 %tid, i32 inreg %cond, ptr addrspace(1) %dummyaddr) { ; GFX10-LABEL: divergent_i1_phi_uniform_branch: ; GFX10: ; %bb.0: ; %A ; GFX10-NEXT: s_cmp_lg_u32 s0, 0 ; GFX10-NEXT: s_cbranch_scc0 .LBB0_2 ; GFX10-NEXT: ; %bb.1: ; GFX10-NEXT: v_cmp_le_u32_e64 s0, 6, v2 ; GFX10-NEXT: s_branch .LBB0_3 ; GFX10-NEXT: .LBB0_2: ; %dummy ; GFX10-NEXT: v_mov_b32_e32 v5, 0x7b ; GFX10-NEXT: v_cmp_gt_u32_e64 s0, 1, v2 ; GFX10-NEXT: global_store_dword v[3:4], v5, off ; GFX10-NEXT: .LBB0_3: ; %exit ; GFX10-NEXT: v_cndmask_b32_e64 v2, 0, -1, s0 ; GFX10-NEXT: v_add_nc_u32_e32 v2, 2, v2 ; GFX10-NEXT: global_store_dword v[0:1], v2, off ; GFX10-NEXT: s_endpgm A: %val_A = icmp uge i32 %tid, 6 %cmp = icmp eq i32 %cond, 0 br i1 %cmp, label %dummy, label %exit dummy: store i32 123, ptr addrspace(1) %dummyaddr br label %B B: %val_B = icmp ult i32 %tid, 1 br label %exit exit: %phi = phi i1 [ %val_A, %A ], [ %val_B, %B ] %sel = select i1 %phi, i32 1, i32 2 store i32 %sel, ptr addrspace(1) %out ret void } ; Fix me - there is no need to merge lane masks here define amdgpu_ps void @divergent_i1_phi_uniform_branch_simple(ptr addrspace(1) %out, i32 %tid, i32 inreg %cond) { ; GFX10-LABEL: divergent_i1_phi_uniform_branch_simple: ; GFX10: ; %bb.0: ; %A ; GFX10-NEXT: s_cmp_lg_u32 s0, 0 ; GFX10-NEXT: s_cbranch_scc0 .LBB1_2 ; GFX10-NEXT: ; %bb.1: ; GFX10-NEXT: v_cmp_le_u32_e64 s0, 6, v2 ; GFX10-NEXT: s_branch .LBB1_3 ; GFX10-NEXT: .LBB1_2: ; %B ; GFX10-NEXT: v_cmp_gt_u32_e64 s0, 1, v2 ; GFX10-NEXT: .LBB1_3: ; %exit ; GFX10-NEXT: v_cndmask_b32_e64 v2, 0, -1, s0 ; GFX10-NEXT: v_add_nc_u32_e32 v2, 2, v2 ; GFX10-NEXT: global_store_dword v[0:1], v2, off ; GFX10-NEXT: s_endpgm A: %val_A = icmp uge i32 %tid, 6 %cmp = icmp eq i32 %cond, 0 br i1 %cmp, label %B, label %exit B: %val_B = icmp ult i32 %tid, 1 br label %exit exit: %phi = phi i1 [ %val_A, %A ], [ %val_B, %B ] %sel = select i1 %phi, i32 1, i32 2 store i32 %sel, ptr addrspace(1) %out ret void } ; Divergent i1 phi that uses value from previous iteration. ; Used only inside the loop (variable name is bool_counter) define void @divergent_i1_phi_used_inside_loop(float %val, ptr %addr) { ; GFX10-LABEL: divergent_i1_phi_used_inside_loop: ; GFX10: ; %bb.0: ; %entry ; GFX10-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) ; GFX10-NEXT: s_mov_b32 s4, 0 ; GFX10-NEXT: v_mov_b32_e32 v3, 1 ; GFX10-NEXT: v_mov_b32_e32 v4, s4 ; GFX10-NEXT: .LBB2_1: ; %loop ; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1 ; GFX10-NEXT: v_cvt_f32_u32_e32 v5, v4 ; GFX10-NEXT: v_xor_b32_e32 v3, 1, v3 ; GFX10-NEXT: v_add_nc_u32_e32 v4, 1, v4 ; GFX10-NEXT: v_cmp_gt_f32_e32 vcc_lo, v5, v0 ; GFX10-NEXT: s_or_b32 s4, vcc_lo, s4 ; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s4 ; GFX10-NEXT: s_cbranch_execnz .LBB2_1 ; GFX10-NEXT: ; %bb.2: ; %exit ; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s4 ; GFX10-NEXT: v_and_b32_e32 v0, 1, v3 ; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v0 ; GFX10-NEXT: v_cndmask_b32_e64 v0, 0, 1.0, vcc_lo ; GFX10-NEXT: flat_store_dword v[1:2], v0 ; GFX10-NEXT: s_waitcnt lgkmcnt(0) ; GFX10-NEXT: s_setpc_b64 s[30:31] entry: br label %loop loop: %counter = phi i32 [ 0, %entry ], [ %counterPlus1, %loop ] %bool_counter = phi i1 [ true, %entry ], [ %neg_bool_counter, %loop ] %neg_bool_counter = xor i1 %bool_counter, true %fcounter = uitofp i32 %counter to float %cond = fcmp ogt float %fcounter, %val %counterPlus1 = add i32 %counter, 1 br i1 %cond, label %exit, label %loop exit: %select = select i1 %neg_bool_counter, float 1.000000e+00, float 0.000000e+00 store float %select, ptr %addr ret void } define void @divergent_i1_phi_used_inside_loop_bigger_loop_body(float %val, float %pre_cond_val, ptr %addr, ptr %addr_if, ptr %addr_else) { ; GFX10-LABEL: divergent_i1_phi_used_inside_loop_bigger_loop_body: ; GFX10: ; %bb.0: ; %entry ; GFX10-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) ; GFX10-NEXT: v_cmp_lt_f32_e32 vcc_lo, 1.0, v1 ; GFX10-NEXT: s_mov_b32 s4, 0 ; GFX10-NEXT: v_mov_b32_e32 v8, 0x3e8 ; GFX10-NEXT: v_mov_b32_e32 v9, s4 ; GFX10-NEXT: v_cndmask_b32_e64 v1, 0, 1, vcc_lo ; GFX10-NEXT: s_branch .LBB3_2 ; GFX10-NEXT: .LBB3_1: ; %loop_body ; GFX10-NEXT: ; in Loop: Header=BB3_2 Depth=1 ; GFX10-NEXT: v_cvt_f32_u32_e32 v10, v9 ; GFX10-NEXT: v_xor_b32_e32 v1, 1, v1 ; GFX10-NEXT: v_add_nc_u32_e32 v9, 1, v9 ; GFX10-NEXT: v_cmp_gt_f32_e32 vcc_lo, v10, v0 ; GFX10-NEXT: s_or_b32 s4, vcc_lo, s4 ; GFX10-NEXT: s_andn2_b32 exec_lo, exec_lo, s4 ; GFX10-NEXT: s_cbranch_execz .LBB3_6 ; GFX10-NEXT: .LBB3_2: ; %loop_start ; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1 ; GFX10-NEXT: v_cmp_ge_i32_e32 vcc_lo, 0x3e8, v9 ; GFX10-NEXT: s_mov_b32 s5, 1 ; GFX10-NEXT: s_cbranch_vccz .LBB3_4 ; GFX10-NEXT: ; %bb.3: ; %else ; GFX10-NEXT: ; in Loop: Header=BB3_2 Depth=1 ; GFX10-NEXT: s_mov_b32 s5, 0 ; GFX10-NEXT: flat_store_dword v[6:7], v8 ; GFX10-NEXT: .LBB3_4: ; %Flow ; GFX10-NEXT: ; in Loop: Header=BB3_2 Depth=1 ; GFX10-NEXT: s_xor_b32 s5, s5, 1 ; GFX10-NEXT: s_and_b32 s5, s5, 1 ; GFX10-NEXT: s_cmp_lg_u32 s5, 0 ; GFX10-NEXT: s_cbranch_scc1 .LBB3_1 ; GFX10-NEXT: ; %bb.5: ; %if ; GFX10-NEXT: ; in Loop: Header=BB3_2 Depth=1 ; GFX10-NEXT: flat_store_dword v[4:5], v8 ; GFX10-NEXT: s_branch .LBB3_1 ; GFX10-NEXT: .LBB3_6: ; %exit ; GFX10-NEXT: s_or_b32 exec_lo, exec_lo, s4 ; GFX10-NEXT: v_and_b32_e32 v0, 1, v1 ; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v0 ; GFX10-NEXT: v_cndmask_b32_e64 v0, 0, 1.0, vcc_lo ; GFX10-NEXT: flat_store_dword v[2:3], v0 ; GFX10-NEXT: s_waitcnt lgkmcnt(0) ; GFX10-NEXT: s_setpc_b64 s[30:31] entry: %pre_cond = fcmp ogt float %pre_cond_val, 1.0 br label %loop_start loop_start: %counter = phi i32 [ 0, %entry ], [ %counterPlus1, %loop_body ] %bool_counter = phi i1 [ %pre_cond, %entry ], [ %neg_bool_counter, %loop_body ] %cond_break = icmp sgt i32 %counter, 1000 br i1 %cond_break, label %if, label %else if: store i32 1000, ptr %addr_if br label %loop_body else: store i32 1000, ptr %addr_else br label %loop_body loop_body: %neg_bool_counter = xor i1 %bool_counter, true %fcounter = uitofp i32 %counter to float %cond = fcmp ogt float %fcounter, %val %counterPlus1 = add i32 %counter, 1 br i1 %cond, label %exit, label %loop_start exit: %select = select i1 %neg_bool_counter, float 1.000000e+00, float 0.000000e+00 store float %select, ptr %addr ret void } ; There is a divergent, according to machine uniformity info, g_brcond branch ; here, not lowered to si_if because of "amdgpu-flat-work-group-size"="1,1". define amdgpu_cs void @single_lane_execution_attribute(i32 inreg %.userdata0, <3 x i32> inreg %.WorkgroupId, <3 x i32> %.LocalInvocationId) #0 { ; GFX10-LABEL: single_lane_execution_attribute: ; GFX10: ; %bb.0: ; %.entry ; GFX10-NEXT: s_mov_b32 s12, 0 ; GFX10-NEXT: s_getpc_b64 s[4:5] ; GFX10-NEXT: s_mov_b32 s13, -1 ; GFX10-NEXT: s_mov_b32 s2, s0 ; GFX10-NEXT: s_and_b64 s[4:5], s[4:5], s[12:13] ; GFX10-NEXT: s_mov_b32 s3, s12 ; GFX10-NEXT: v_mbcnt_lo_u32_b32 v1, -1, 0 ; GFX10-NEXT: s_or_b64 s[2:3], s[4:5], s[2:3] ; GFX10-NEXT: s_load_dwordx8 s[4:11], s[2:3], 0x0 ; GFX10-NEXT: s_mov_b32 s2, 1 ; GFX10-NEXT: v_mbcnt_hi_u32_b32 v1, -1, v1 ; GFX10-NEXT: v_lshlrev_b32_e32 v2, 2, v1 ; GFX10-NEXT: v_and_b32_e32 v3, 1, v1 ; GFX10-NEXT: v_xor_b32_e32 v3, 1, v3 ; GFX10-NEXT: v_and_b32_e32 v3, 1, v3 ; GFX10-NEXT: s_waitcnt lgkmcnt(0) ; GFX10-NEXT: buffer_load_dword v2, v2, s[4:7], 0 offen ; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v3 ; GFX10-NEXT: ; implicit-def: $vgpr3 ; GFX10-NEXT: s_waitcnt vmcnt(0) ; GFX10-NEXT: v_cmp_eq_u32_e64 s0, 0, v2 ; GFX10-NEXT: s_cbranch_vccnz .LBB4_4 ; GFX10-NEXT: ; %bb.1: ; %.preheader.preheader ; GFX10-NEXT: v_mov_b32_e32 v3, s12 ; GFX10-NEXT: v_mov_b32_e32 v4, s12 ; GFX10-NEXT: .LBB4_2: ; %.preheader ; GFX10-NEXT: ; =>This Inner Loop Header: Depth=1 ; GFX10-NEXT: buffer_load_dword v5, v3, s[4:7], 0 offen ; GFX10-NEXT: v_add_nc_u32_e32 v1, -1, v1 ; GFX10-NEXT: v_add_nc_u32_e32 v3, 4, v3 ; GFX10-NEXT: v_cmp_ne_u32_e32 vcc_lo, 0, v1 ; GFX10-NEXT: s_waitcnt vmcnt(0) ; GFX10-NEXT: v_add_nc_u32_e32 v4, v5, v4 ; GFX10-NEXT: s_cbranch_vccnz .LBB4_2 ; GFX10-NEXT: ; %bb.3: ; %.preheader._crit_edge ; GFX10-NEXT: v_cmp_eq_u32_e32 vcc_lo, v4, v2 ; GFX10-NEXT: s_or_b32 s2, s0, vcc_lo ; GFX10-NEXT: v_cndmask_b32_e64 v3, 0, 1, s2 ; GFX10-NEXT: s_mov_b32 s2, 0 ; GFX10-NEXT: .LBB4_4: ; %Flow ; GFX10-NEXT: s_and_b32 s2, s2, 1 ; GFX10-NEXT: s_cmp_lg_u32 s2, 0 ; GFX10-NEXT: s_cbranch_scc0 .LBB4_6 ; GFX10-NEXT: ; %bb.5: ; %.19 ; GFX10-NEXT: v_cndmask_b32_e64 v1, 0, 1, s0 ; GFX10-NEXT: v_or_b32_e32 v3, 2, v1 ; GFX10-NEXT: .LBB4_6: ; %.22 ; GFX10-NEXT: v_add_lshl_u32 v0, v0, s1, 2 ; GFX10-NEXT: buffer_store_dword v3, v0, s[8:11], 0 offen ; GFX10-NEXT: s_endpgm .entry: %.0 = call i64 @llvm.amdgcn.s.getpc() %.1 = and i64 %.0, -4294967296 %.2 = zext i32 %.userdata0 to i64 %.3 = or i64 %.1, %.2 %.4 = inttoptr i64 %.3 to ptr addrspace(4) %.5 = getelementptr i8, ptr addrspace(4) %.4, i64 16 %.6 = load <4 x i32>, ptr addrspace(4) %.5, align 16 %.7 = load <4 x i32>, ptr addrspace(4) %.4, align 16 %.8 = call i32 @llvm.amdgcn.mbcnt.lo(i32 -1, i32 0) %.9 = call i32 @llvm.amdgcn.mbcnt.hi(i32 -1, i32 %.8) %.fr11 = freeze i32 %.9 %.idx = shl i32 %.fr11, 2 %.10 = call i32 @llvm.amdgcn.raw.buffer.load.i32(<4 x i32> %.7, i32 %.idx, i32 0, i32 0) %.11 = icmp eq i32 %.10, 0 %.12 = and i32 %.fr11, 1 %.not = icmp eq i32 %.12, 0 br i1 %.not, label %.19, label %.preheader .preheader: ; preds = %.entry, %.preheader %._96.02 = phi i32 [ %.15, %.preheader ], [ 0, %.entry ] %._50.01 = phi i32 [ %.14, %.preheader ], [ 0, %.entry ] %.idx5 = shl i32 %._96.02, 2 %.13 = call i32 @llvm.amdgcn.raw.buffer.load.i32(<4 x i32> %.7, i32 %.idx5, i32 0, i32 0) %.14 = add i32 %.13, %._50.01 %.15 = add nuw i32 %._96.02, 1 %.exitcond.not = icmp eq i32 %.15, %.fr11 br i1 %.exitcond.not, label %.preheader._crit_edge, label %.preheader .preheader._crit_edge: ; preds = %.preheader %.16 = icmp eq i32 %.14, %.10 %.17 = or i1 %.11, %.16 %.18 = zext i1 %.17 to i32 br label %.22 .19: ; preds = %.entry %.20 = zext i1 %.11 to i32 %.21 = or i32 %.20, 2 br label %.22 .22: ; preds = %.19, %.preheader._crit_edge %._51.0 = phi i32 [ %.18, %.preheader._crit_edge ], [ %.21, %.19 ] %.WorkgroupId.i0 = extractelement <3 x i32> %.WorkgroupId, i64 0 %.LocalInvocationId.i0 = extractelement <3 x i32> %.LocalInvocationId, i64 0 %.i0 = add i32 %.LocalInvocationId.i0, %.WorkgroupId.i0 %.idx6 = shl i32 %.i0, 2 call void @llvm.amdgcn.raw.buffer.store.i32(i32 %._51.0, <4 x i32> %.6, i32 %.idx6, i32 0, i32 0) ret void } ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(none) declare i32 @llvm.amdgcn.mbcnt.lo(i32, i32) ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(none) declare i32 @llvm.amdgcn.mbcnt.hi(i32, i32) ; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none) declare i64 @llvm.amdgcn.s.getpc() ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(read) declare i32 @llvm.amdgcn.raw.buffer.load.i32(<4 x i32>, i32, i32, i32 immarg) ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(write) declare void @llvm.amdgcn.raw.buffer.store.i32(i32, <4 x i32>, i32, i32, i32 immarg) attributes #0 = { nounwind memory(readwrite) "amdgpu-flat-work-group-size"="1,1" }