1; RUN: opt -mtriple=amdgcn-- -S -structurizecfg -si-annotate-control-flow %s | FileCheck -check-prefix=IR %s 2; RUN: llc -march=amdgcn -mcpu=hawaii -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s 3 4; After structurizing, there are 3 levels of loops. The i1 phi 5; conditions mutually depend on each other, so it isn't safe to delete 6; the condition that appears to have no uses until the loop is 7; completely processed. 8 9 10; IR-LABEL: @reduced_nested_loop_conditions( 11 12; IR: bb5: 13; IR-NEXT: %phi.broken = phi i64 [ %loop.phi, %bb10 ], [ 0, %bb ] 14; IR-NEXT: %tmp6 = phi i32 [ 0, %bb ], [ %tmp11, %bb10 ] 15; IR-NEXT: %tmp7 = icmp eq i32 %tmp6, 1 16; IR-NEXT: %0 = call { i1, i64 } @llvm.amdgcn.if(i1 %tmp7) 17; IR-NEXT: %1 = extractvalue { i1, i64 } %0, 0 18; IR-NEXT: %2 = extractvalue { i1, i64 } %0, 1 19; IR-NEXT: br i1 %1, label %bb8, label %Flow 20 21; IR: bb8: 22; IR-NEXT: %3 = call i64 @llvm.amdgcn.break(i64 %phi.broken) 23; IR-NEXT: br label %bb13 24 25; IR: bb10: 26; IR-NEXT: %loop.phi = phi i64 [ %6, %Flow ] 27; IR-NEXT: %tmp11 = phi i32 [ %5, %Flow ] 28; IR-NEXT: %4 = call i1 @llvm.amdgcn.loop(i64 %loop.phi) 29; IR-NEXT: br i1 %4, label %bb23, label %bb5 30 31; IR: Flow: 32; IR-NEXT: %loop.phi1 = phi i64 [ %loop.phi2, %bb4 ], [ %phi.broken, %bb5 ] 33; IR-NEXT: %5 = phi i32 [ %tmp21, %bb4 ], [ undef, %bb5 ] 34; IR-NEXT: %6 = call i64 @llvm.amdgcn.else.break(i64 %2, i64 %loop.phi1) 35; IR-NEXT: call void @llvm.amdgcn.end.cf(i64 %2) 36; IR-NEXT: br label %bb10 37 38; IR: bb13: 39; IR-NEXT: %loop.phi3 = phi i64 [ %loop.phi4, %bb3 ], [ %3, %bb8 ] 40; IR-NEXT: %tmp14 = phi i1 [ false, %bb3 ], [ true, %bb8 ] 41; IR-NEXT: %tmp15 = bitcast i64 %tmp2 to <2 x i32> 42; IR-NEXT: br i1 %tmp14, label %bb16, label %bb20 43 44; IR: bb16: 45; IR-NEXT: %tmp17 = extractelement <2 x i32> %tmp15, i64 1 46; IR-NEXT: %tmp18 = getelementptr inbounds i32, i32 addrspace(3)* undef, i32 %tmp17 47; IR-NEXT: %tmp19 = load volatile i32, i32 addrspace(3)* %tmp18 48; IR-NEXT: br label %bb20 49 50; IR: bb20: 51; IR-NEXT: %loop.phi4 = phi i64 [ %phi.broken, %bb16 ], [ %phi.broken, %bb13 ] 52; IR-NEXT: %loop.phi2 = phi i64 [ %phi.broken, %bb16 ], [ %loop.phi3, %bb13 ] 53; IR-NEXT: %tmp21 = phi i32 [ %tmp19, %bb16 ], [ 0, %bb13 ] 54; IR-NEXT: br label %bb9 55 56; IR: bb23: 57; IR-NEXT: call void @llvm.amdgcn.end.cf(i64 %loop.phi) 58; IR-NEXT: ret void 59 60; GCN-LABEL: {{^}}reduced_nested_loop_conditions: 61 62; GCN: s_cmp_eq_u32 s{{[0-9]+}}, 1 63; GCN-NEXT: s_cbranch_scc1 64 65; FIXME: Should fold to unconditional branch? 66; GCN: ; implicit-def 67; GCN: s_cbranch_vccz 68 69; GCN: ds_read_b32 70 71; GCN: [[BB9:BB[0-9]+_[0-9]+]]: ; %bb9 72; GCN-NEXT: ; =>This Inner Loop Header: Depth=1 73; GCN-NEXT: s_branch [[BB9]] 74define amdgpu_kernel void @reduced_nested_loop_conditions(i64 addrspace(3)* nocapture %arg) #0 { 75bb: 76 %tmp = tail call i32 @llvm.amdgcn.workitem.id.x() #1 77 %tmp1 = getelementptr inbounds i64, i64 addrspace(3)* %arg, i32 %tmp 78 %tmp2 = load volatile i64, i64 addrspace(3)* %tmp1 79 br label %bb5 80 81bb3: ; preds = %bb9 82 br i1 true, label %bb4, label %bb13 83 84bb4: ; preds = %bb3 85 br label %bb10 86 87bb5: ; preds = %bb10, %bb 88 %tmp6 = phi i32 [ 0, %bb ], [ %tmp11, %bb10 ] 89 %tmp7 = icmp eq i32 %tmp6, 1 90 br i1 %tmp7, label %bb8, label %bb10 91 92bb8: ; preds = %bb5 93 br label %bb13 94 95bb9: ; preds = %bb20, %bb9 96 br i1 false, label %bb3, label %bb9 97 98bb10: ; preds = %bb5, %bb4 99 %tmp11 = phi i32 [ %tmp21, %bb4 ], [ undef, %bb5 ] 100 %tmp12 = phi i1 [ %tmp22, %bb4 ], [ true, %bb5 ] 101 br i1 %tmp12, label %bb23, label %bb5 102 103bb13: ; preds = %bb8, %bb3 104 %tmp14 = phi i1 [ %tmp22, %bb3 ], [ true, %bb8 ] 105 %tmp15 = bitcast i64 %tmp2 to <2 x i32> 106 br i1 %tmp14, label %bb16, label %bb20 107 108bb16: ; preds = %bb13 109 %tmp17 = extractelement <2 x i32> %tmp15, i64 1 110 %tmp18 = getelementptr inbounds i32, i32 addrspace(3)* undef, i32 %tmp17 111 %tmp19 = load volatile i32, i32 addrspace(3)* %tmp18 112 br label %bb20 113 114bb20: ; preds = %bb16, %bb13 115 %tmp21 = phi i32 [ %tmp19, %bb16 ], [ 0, %bb13 ] 116 %tmp22 = phi i1 [ false, %bb16 ], [ %tmp14, %bb13 ] 117 br label %bb9 118 119bb23: ; preds = %bb10 120 ret void 121} 122 123; Earlier version of above, before a run of the structurizer. 124; IR-LABEL: @nested_loop_conditions( 125 126; IR: %tmp1235 = icmp slt i32 %tmp1134, 9 127; IR: br i1 %tmp1235, label %bb14.lr.ph, label %Flow 128 129; IR: bb14.lr.ph: 130; IR: br label %bb14 131 132; IR: Flow3: 133; IR: call void @llvm.amdgcn.end.cf(i64 %18) 134; IR: %0 = call { i1, i64 } @llvm.amdgcn.if(i1 %17) 135; IR: %1 = extractvalue { i1, i64 } %0, 0 136; IR: %2 = extractvalue { i1, i64 } %0, 1 137; IR: br i1 %1, label %bb4.bb13_crit_edge, label %Flow4 138 139; IR: bb4.bb13_crit_edge: 140; IR: br label %Flow4 141 142; IR: Flow4: 143; IR: %3 = phi i1 [ true, %bb4.bb13_crit_edge ], [ false, %Flow3 ] 144; IR: call void @llvm.amdgcn.end.cf(i64 %2) 145; IR: br label %Flow 146 147; IR: bb13: 148; IR: br label %bb31 149 150; IR: Flow: 151; IR: %4 = phi i1 [ %3, %Flow4 ], [ true, %bb ] 152; IR: %5 = call { i1, i64 } @llvm.amdgcn.if(i1 %4) 153; IR: %6 = extractvalue { i1, i64 } %5, 0 154; IR: %7 = extractvalue { i1, i64 } %5, 1 155; IR: br i1 %6, label %bb13, label %bb31 156 157; IR: bb14: 158; IR: %phi.broken = phi i64 [ %18, %Flow2 ], [ 0, %bb14.lr.ph ] 159; IR: %tmp1037 = phi i32 [ %tmp1033, %bb14.lr.ph ], [ %16, %Flow2 ] 160; IR: %tmp936 = phi <4 x i32> [ %tmp932, %bb14.lr.ph ], [ %15, %Flow2 ] 161; IR: %tmp15 = icmp eq i32 %tmp1037, 1 162; IR: %8 = xor i1 %tmp15, true 163; IR: %9 = call { i1, i64 } @llvm.amdgcn.if(i1 %8) 164; IR: %10 = extractvalue { i1, i64 } %9, 0 165; IR: %11 = extractvalue { i1, i64 } %9, 1 166; IR: br i1 %10, label %bb31.loopexit, label %Flow1 167 168; IR: Flow1: 169; IR: %12 = call { i1, i64 } @llvm.amdgcn.else(i64 %11) 170; IR: %13 = extractvalue { i1, i64 } %12, 0 171; IR: %14 = extractvalue { i1, i64 } %12, 1 172; IR: br i1 %13, label %bb16, label %Flow2 173 174; IR: bb16: 175; IR: %tmp17 = bitcast i64 %tmp3 to <2 x i32> 176; IR: br label %bb18 177 178; IR: Flow2: 179; IR: %loop.phi = phi i64 [ %21, %bb21 ], [ %phi.broken, %Flow1 ] 180; IR: %15 = phi <4 x i32> [ %tmp9, %bb21 ], [ undef, %Flow1 ] 181; IR: %16 = phi i32 [ %tmp10, %bb21 ], [ undef, %Flow1 ] 182; IR: %17 = phi i1 [ %20, %bb21 ], [ false, %Flow1 ] 183; IR: %18 = call i64 @llvm.amdgcn.else.break(i64 %14, i64 %loop.phi) 184; IR: call void @llvm.amdgcn.end.cf(i64 %14) 185; IR: %19 = call i1 @llvm.amdgcn.loop(i64 %18) 186; IR: br i1 %19, label %Flow3, label %bb14 187 188; IR: bb18: 189; IR: %tmp19 = load volatile i32, i32 addrspace(1)* undef 190; IR: %tmp20 = icmp slt i32 %tmp19, 9 191; IR: br i1 %tmp20, label %bb21, label %bb18 192 193; IR: bb21: 194; IR: %tmp22 = extractelement <2 x i32> %tmp17, i64 1 195; IR: %tmp23 = lshr i32 %tmp22, 16 196; IR: %tmp24 = select i1 undef, i32 undef, i32 %tmp23 197; IR: %tmp25 = uitofp i32 %tmp24 to float 198; IR: %tmp26 = fmul float %tmp25, 0x3EF0001000000000 199; IR: %tmp27 = fsub float %tmp26, undef 200; IR: %tmp28 = fcmp olt float %tmp27, 5.000000e-01 201; IR: %tmp29 = select i1 %tmp28, i64 1, i64 2 202; IR: %tmp30 = extractelement <4 x i32> %tmp936, i64 %tmp29 203; IR: %tmp7 = zext i32 %tmp30 to i64 204; IR: %tmp8 = getelementptr inbounds <4 x i32>, <4 x i32> addrspace(1)* undef, i64 %tmp7 205; IR: %tmp9 = load <4 x i32>, <4 x i32> addrspace(1)* %tmp8, align 16 206; IR: %tmp10 = extractelement <4 x i32> %tmp9, i64 0 207; IR: %tmp11 = load volatile i32, i32 addrspace(1)* undef 208; IR: %tmp12 = icmp slt i32 %tmp11, 9 209; IR: %20 = xor i1 %tmp12, true 210; IR: %21 = call i64 @llvm.amdgcn.if.break(i1 %20, i64 %phi.broken) 211; IR: br label %Flow2 212 213; IR: bb31.loopexit: 214; IR: br label %Flow1 215 216; IR: bb31: 217; IR: call void @llvm.amdgcn.end.cf(i64 %7) 218; IR: store volatile i32 0, i32 addrspace(1)* undef 219; IR: ret void 220 221 222; GCN-LABEL: {{^}}nested_loop_conditions: 223 224; GCN: v_cmp_lt_i32_e32 vcc, 8, v 225; GCN: s_and_b64 vcc, exec, vcc 226; GCN: s_cbranch_vccnz [[BB31:BB[0-9]+_[0-9]+]] 227 228; GCN: [[BB14:BB[0-9]+_[0-9]+]]: ; %bb14 229; GCN: v_cmp_ne_u32_e32 vcc, 1, v 230; GCN-NEXT: s_and_b64 vcc, exec, vcc 231; GCN-NEXT: s_cbranch_vccnz [[BB31]] 232 233; GCN: [[BB18:BB[0-9]+_[0-9]+]]: ; %bb18 234; GCN: buffer_load_dword 235; GCN: v_cmp_lt_i32_e32 vcc, 8, v 236; GCN-NEXT: s_and_b64 vcc, exec, vcc 237; GCN-NEXT: s_cbranch_vccnz [[BB18]] 238 239; GCN: buffer_load_dword 240; GCN: buffer_load_dword 241; GCN: v_cmp_gt_i32_e32 vcc, 9 242; GCN-NEXT: s_and_b64 vcc, exec, vcc 243; GCN-NEXT: s_cbranch_vccnz [[BB14]] 244 245; GCN: [[BB31]]: 246; GCN: buffer_store_dword 247; GCN: s_endpgm 248define amdgpu_kernel void @nested_loop_conditions(i64 addrspace(1)* nocapture %arg) #0 { 249bb: 250 %tmp = tail call i32 @llvm.amdgcn.workitem.id.x() #1 251 %tmp1 = zext i32 %tmp to i64 252 %tmp2 = getelementptr inbounds i64, i64 addrspace(1)* %arg, i64 %tmp1 253 %tmp3 = load i64, i64 addrspace(1)* %tmp2, align 16 254 %tmp932 = load <4 x i32>, <4 x i32> addrspace(1)* undef, align 16 255 %tmp1033 = extractelement <4 x i32> %tmp932, i64 0 256 %tmp1134 = load volatile i32, i32 addrspace(1)* undef 257 %tmp1235 = icmp slt i32 %tmp1134, 9 258 br i1 %tmp1235, label %bb14.lr.ph, label %bb13 259 260bb14.lr.ph: ; preds = %bb 261 br label %bb14 262 263bb4.bb13_crit_edge: ; preds = %bb21 264 br label %bb13 265 266bb13: ; preds = %bb4.bb13_crit_edge, %bb 267 br label %bb31 268 269bb14: ; preds = %bb21, %bb14.lr.ph 270 %tmp1037 = phi i32 [ %tmp1033, %bb14.lr.ph ], [ %tmp10, %bb21 ] 271 %tmp936 = phi <4 x i32> [ %tmp932, %bb14.lr.ph ], [ %tmp9, %bb21 ] 272 %tmp15 = icmp eq i32 %tmp1037, 1 273 br i1 %tmp15, label %bb16, label %bb31.loopexit 274 275bb16: ; preds = %bb14 276 %tmp17 = bitcast i64 %tmp3 to <2 x i32> 277 br label %bb18 278 279bb18: ; preds = %bb18, %bb16 280 %tmp19 = load volatile i32, i32 addrspace(1)* undef 281 %tmp20 = icmp slt i32 %tmp19, 9 282 br i1 %tmp20, label %bb21, label %bb18 283 284bb21: ; preds = %bb18 285 %tmp22 = extractelement <2 x i32> %tmp17, i64 1 286 %tmp23 = lshr i32 %tmp22, 16 287 %tmp24 = select i1 undef, i32 undef, i32 %tmp23 288 %tmp25 = uitofp i32 %tmp24 to float 289 %tmp26 = fmul float %tmp25, 0x3EF0001000000000 290 %tmp27 = fsub float %tmp26, undef 291 %tmp28 = fcmp olt float %tmp27, 5.000000e-01 292 %tmp29 = select i1 %tmp28, i64 1, i64 2 293 %tmp30 = extractelement <4 x i32> %tmp936, i64 %tmp29 294 %tmp7 = zext i32 %tmp30 to i64 295 %tmp8 = getelementptr inbounds <4 x i32>, <4 x i32> addrspace(1)* undef, i64 %tmp7 296 %tmp9 = load <4 x i32>, <4 x i32> addrspace(1)* %tmp8, align 16 297 %tmp10 = extractelement <4 x i32> %tmp9, i64 0 298 %tmp11 = load volatile i32, i32 addrspace(1)* undef 299 %tmp12 = icmp slt i32 %tmp11, 9 300 br i1 %tmp12, label %bb14, label %bb4.bb13_crit_edge 301 302bb31.loopexit: ; preds = %bb14 303 br label %bb31 304 305bb31: ; preds = %bb31.loopexit, %bb13 306 store volatile i32 0, i32 addrspace(1)* undef 307 ret void 308} 309 310declare i32 @llvm.amdgcn.workitem.id.x() #1 311 312attributes #0 = { nounwind } 313attributes #1 = { nounwind readnone } 314