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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt -S -passes=instcombine < %s | FileCheck %s3 4; Check if a value can be deduced as a power of 2, allowing urem optimization.5; i.e. A urem B = A & (B - 1) if B is a power of 2.6 7define i64 @known_power_of_two_urem_phi(i64 %size, i1 %cmp, i1 %cmp1) {8; CHECK-LABEL: @known_power_of_two_urem_phi(9; CHECK-NEXT: entry:10; CHECK-NEXT: br i1 [[CMP:%.*]], label [[COND_TRUE:%.*]], label [[COND_END:%.*]]11; CHECK: cond.true:12; CHECK-NEXT: br i1 [[CMP1:%.*]], label [[COND_TRUE_TRUE:%.*]], label [[COND_TRUE_FALSE:%.*]]13; CHECK: cond.true.true:14; CHECK-NEXT: br label [[COND_TRUE_END:%.*]]15; CHECK: cond.true.false:16; CHECK-NEXT: br label [[COND_TRUE_END]]17; CHECK: cond.true.end:18; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ 1, [[COND_TRUE_TRUE]] ], [ 3, [[COND_TRUE_FALSE]] ]19; CHECK-NEXT: br label [[COND_END]]20; CHECK: cond.end:21; CHECK-NEXT: [[PHI1:%.*]] = phi i64 [ 4095, [[ENTRY:%.*]] ], [ [[PHI]], [[COND_TRUE_END]] ]22; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[PHI1]]23; CHECK-NEXT: ret i64 [[UREM]]24;25entry:26 br i1 %cmp, label %cond.true, label %cond.end27 28cond.true:29 br i1 %cmp1, label %cond.true.true, label %cond.true.false30 31cond.true.true:32 br label %cond.true.end33 34cond.true.false:35 br label %cond.true.end36 37cond.true.end:38 %phi = phi i64 [ 2, %cond.true.true ], [ 4, %cond.true.false ]39 br label %cond.end40 41cond.end:42 %phi1 = phi i64 [ 4096, %entry ], [ %phi, %cond.true.end ]43 %urem = urem i64 %size, %phi144 ret i64 %urem45}46 47define i64 @known_power_of_two_urem_nested_expr(i64 %size, i1 %cmp, i1 %cmp1, i64 %0) {48; CHECK-LABEL: @known_power_of_two_urem_nested_expr(49; CHECK-NEXT: entry:50; CHECK-NEXT: br i1 [[CMP:%.*]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]51; CHECK: cond.true:52; CHECK-NEXT: [[TMP1:%.*]] = shl nuw i64 1, [[TMP0:%.*]]53; CHECK-NEXT: br label [[COND_END:%.*]]54; CHECK: cond.false:55; CHECK-NEXT: [[SELECT:%.*]] = select i1 [[CMP1:%.*]], i64 2, i64 856; CHECK-NEXT: br label [[COND_END]]57; CHECK: cond.end:58; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[SELECT]], [[COND_FALSE]] ], [ [[TMP1]], [[COND_TRUE]] ], [ [[PHI]], [[COND_END]] ]59; CHECK-NEXT: [[TMP2:%.*]] = add i64 [[PHI]], -160; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[TMP2]]61; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i64 [[UREM]], 1062; CHECK-NEXT: br i1 [[CMP2]], label [[COND_END]], label [[END:%.*]]63; CHECK: end:64; CHECK-NEXT: ret i64 [[UREM]]65;66entry:67 br i1 %cmp, label %cond.true, label %cond.false68 69cond.true:70 %1 = shl nuw i64 1, %071 br label %cond.end72 73cond.false:74 %select = select i1 %cmp1, i64 2, i64 875 br label %cond.end76 77cond.end:78 %phi = phi i64 [ %select, %cond.false ], [ %1, %cond.true ], [ %phi, %cond.end ]79 %2 = phi i64 [ %size, %cond.false ], [ %size, %cond.true ], [ %0, %cond.end ]80 %urem = urem i64 %size, %phi81 %cmp2 = icmp ult i64 %urem, 1082 br i1 %cmp2, label %cond.end, label %end83 84end:85 ret i64 %urem86}87 88define i64 @known_power_of_two_urem_negative(i64 %size, i1 %cmp, i64 %0) {89; urem is not replaced if not all operands are power of 2.90;91; CHECK-LABEL: @known_power_of_two_urem_negative(92; CHECK-NEXT: entry:93; CHECK-NEXT: br i1 [[CMP:%.*]], label [[COND_TRUE:%.*]], label [[COND_END:%.*]]94; CHECK: cond.true:95; CHECK-NEXT: br label [[COND_END]]96; CHECK: cond.end:97; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ 4, [[ENTRY:%.*]] ], [ [[TMP0:%.*]], [[COND_TRUE]] ]98; CHECK-NEXT: [[UREM:%.*]] = urem i64 [[SIZE:%.*]], [[PHI]]99; CHECK-NEXT: ret i64 [[UREM]]100;101entry:102 br i1 %cmp, label %cond.true, label %cond.end103 104cond.true:105 br label %cond.end106 107cond.end:108 %phi = phi i64 [ 4, %entry ], [ %0, %cond.true ]109 %urem = urem i64 %size, %phi110 ret i64 %urem111}112 113define i64 @known_power_of_two_urem_loop_mul(i64 %size, i64 %a) {114; CHECK-LABEL: @known_power_of_two_urem_loop_mul(115; CHECK-NEXT: entry:116; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]117; CHECK-NEXT: br label [[FOR_BODY:%.*]]118; CHECK: for.body:119; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]120; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]121; CHECK-NEXT: [[TMP0:%.*]] = add i64 [[PHI]], -1122; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[TMP0]]123; CHECK-NEXT: [[ADD]] = add nuw i64 [[SUM]], [[UREM]]124; CHECK-NEXT: [[I]] = shl nuw i64 [[PHI]], 2125; CHECK-NEXT: [[ICMP:%.*]] = icmp ult i64 [[PHI]], 25000000126; CHECK-NEXT: br i1 [[ICMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]127; CHECK: for.end:128; CHECK-NEXT: ret i64 [[SUM]]129;130entry:131 %start = shl nuw i64 1, %a132 br label %for.body133 134for.body:135 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]136 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]137 %urem = urem i64 %size, %phi138 %add = add nuw i64 %sum, %urem139 %i = mul nuw i64 %phi, 4140 %icmp = icmp ult i64 %i, 100000000141 br i1 %icmp, label %for.body, label %for.end142 143for.end:144 %r = phi i64 [ %sum, %for.body ]145 ret i64 %r146}147 148define i64 @known_power_of_two_urem_loop_mul_negative(i64 %size, i64 %a) {149; Cannot deduce induction variable is a power of 2 if it is multiplied by 3.150;151; CHECK-LABEL: @known_power_of_two_urem_loop_mul_negative(152; CHECK-NEXT: entry:153; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]154; CHECK-NEXT: br label [[FOR_BODY:%.*]]155; CHECK: for.body:156; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]157; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]158; CHECK-NEXT: [[UREM:%.*]] = urem i64 [[SIZE:%.*]], [[PHI]]159; CHECK-NEXT: [[ADD]] = add nuw i64 [[SUM]], [[UREM]]160; CHECK-NEXT: [[I]] = mul nuw i64 [[PHI]], 3161; CHECK-NEXT: [[ICMP:%.*]] = icmp ult i64 [[PHI]], 33333334162; CHECK-NEXT: br i1 [[ICMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]163; CHECK: for.end:164; CHECK-NEXT: ret i64 [[SUM]]165;166entry:167 %start = shl nuw i64 1, %a168 br label %for.body169 170for.body:171 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]172 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]173 %urem = urem i64 %size, %phi174 %add = add nuw i64 %sum, %urem175 %i = mul nuw i64 %phi, 3176 %icmp = icmp ult i64 %i, 100000000177 br i1 %icmp, label %for.body, label %for.end178 179for.end:180 %r = phi i64 [ %sum, %for.body ]181 ret i64 %r182}183 184define i64 @known_power_of_two_urem_loop_shl(i64 %size, i64 %a) {185; CHECK-LABEL: @known_power_of_two_urem_loop_shl(186; CHECK-NEXT: entry:187; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]188; CHECK-NEXT: br label [[FOR_BODY:%.*]]189; CHECK: for.body:190; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]191; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]192; CHECK-NEXT: [[TMP0:%.*]] = add i64 [[PHI]], -1193; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[TMP0]]194; CHECK-NEXT: [[ADD]] = add nuw i64 [[SUM]], [[UREM]]195; CHECK-NEXT: [[I]] = shl nuw i64 [[PHI]], 1196; CHECK-NEXT: [[ICMP:%.*]] = icmp ult i64 [[PHI]], 50000000197; CHECK-NEXT: br i1 [[ICMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]198; CHECK: for.end:199; CHECK-NEXT: ret i64 [[SUM]]200;201entry:202 %start = shl nuw i64 1, %a203 br label %for.body204 205for.body:206 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]207 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]208 %urem = urem i64 %size, %phi209 %add = add nuw i64 %sum, %urem210 %i = shl nuw i64 %phi, 1211 %icmp = icmp ult i64 %i, 100000000212 br i1 %icmp, label %for.body, label %for.end213 214for.end:215 %r = phi i64 [ %sum, %for.body ]216 ret i64 %r217}218 219define i64 @known_power_of_two_urem_loop_lshr(i64 %size, i64 %a) {220; CHECK-LABEL: @known_power_of_two_urem_loop_lshr(221; CHECK-NEXT: entry:222; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]223; CHECK-NEXT: br label [[FOR_BODY:%.*]]224; CHECK: for.body:225; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]226; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]227; CHECK-NEXT: [[TMP0:%.*]] = add i64 [[PHI]], -1228; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[TMP0]]229; CHECK-NEXT: [[ADD]] = add nuw i64 [[SUM]], [[UREM]]230; CHECK-NEXT: [[I]] = lshr i64 [[PHI]], 1231; CHECK-NEXT: [[ICMP_NOT:%.*]] = icmp eq i64 [[I]], 0232; CHECK-NEXT: br i1 [[ICMP_NOT]], label [[FOR_END:%.*]], label [[FOR_BODY]]233; CHECK: for.end:234; CHECK-NEXT: ret i64 [[SUM]]235;236entry:237 %start = shl nuw i64 1, %a238 br label %for.body239 240for.body:241 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]242 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]243 %urem = urem i64 %size, %phi244 %add = add nuw i64 %sum, %urem245 %i = lshr i64 %phi, 1246 %icmp = icmp ugt i64 %i, 0247 br i1 %icmp, label %for.body, label %for.end248 249for.end:250 %r = phi i64 [ %sum, %for.body ]251 ret i64 %r252}253 254 255define i64 @known_power_of_two_urem_loop_ashr(i64 %size, i64 %a) {256; CHECK-LABEL: @known_power_of_two_urem_loop_ashr(257; CHECK-NEXT: entry:258; CHECK-NEXT: br label [[FOR_BODY:%.*]]259; CHECK: for.body:260; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ 4096, [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]261; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]262; CHECK-NEXT: [[TMP0:%.*]] = add nsw i64 [[PHI]], -1263; CHECK-NEXT: [[UREM:%.*]] = and i64 [[SIZE:%.*]], [[TMP0]]264; CHECK-NEXT: [[ADD]] = add nsw i64 [[SUM]], [[UREM]]265; CHECK-NEXT: [[I]] = lshr i64 [[PHI]], [[A:%.*]]266; CHECK-NEXT: [[ICMP_NOT:%.*]] = icmp eq i64 [[I]], 0267; CHECK-NEXT: br i1 [[ICMP_NOT]], label [[FOR_END:%.*]], label [[FOR_BODY]]268; CHECK: for.end:269; CHECK-NEXT: ret i64 [[SUM]]270;271entry:272 br label %for.body273 274for.body:275 %phi = phi i64 [ 4096, %entry ], [ %i, %for.body ]276 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]277 %urem = urem i64 %size, %phi278 %add = add nsw i64 %sum, %urem279 %i = ashr i64 %phi, %a280 %icmp = icmp ugt i64 %i, 0281 br i1 %icmp, label %for.body, label %for.end282 283for.end:284 %r = phi i64 [ %sum, %for.body ]285 ret i64 %r286}287 288define i64 @known_power_of_two_urem_loop_ashr_negative(i64 %size, i64 %a) {289; Cannot deduce induction variable is a power of 2 for ashr if its starting290; value is equal to sign bit291;292; CHECK-LABEL: @known_power_of_two_urem_loop_ashr_negative(293; CHECK-NEXT: entry:294; CHECK-NEXT: br label [[FOR_BODY:%.*]]295; CHECK: for.body:296; CHECK-NEXT: br i1 true, label [[FOR_BODY]], label [[FOR_END:%.*]]297; CHECK: for.end:298; CHECK-NEXT: ret i64 poison299;300entry:301 br label %for.body302 303for.body:304 %phi = phi i64 [ u0x8000000000000000, %entry ], [ %i, %for.body ]305 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]306 %urem = urem i64 %size, %phi307 %add = add nsw i64 %sum, %urem308 %i = ashr i64 %phi, %a309 %icmp = icmp ugt i64 %i, 1310 br i1 %icmp, label %for.body, label %for.end311 312for.end:313 %r = phi i64 [ %sum, %for.body ]314 ret i64 %r315}316 317define i64 @known_power_of_two_urem_loop_ashr_negative_2(i64 %size, i64 %a) {318; Cannot deduce induction variable is a power of 2 for ashr if its starting319; value may equal to sign bit.320;321; CHECK-LABEL: @known_power_of_two_urem_loop_ashr_negative_2(322; CHECK-NEXT: entry:323; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]324; CHECK-NEXT: br label [[FOR_BODY:%.*]]325; CHECK: for.body:326; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]327; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]328; CHECK-NEXT: [[UREM:%.*]] = urem i64 [[SIZE:%.*]], [[PHI]]329; CHECK-NEXT: [[ADD]] = add nsw i64 [[SUM]], [[UREM]]330; CHECK-NEXT: [[I]] = ashr i64 [[PHI]], 2331; CHECK-NEXT: [[ICMP_NOT:%.*]] = icmp eq i64 [[I]], 0332; CHECK-NEXT: br i1 [[ICMP_NOT]], label [[FOR_END:%.*]], label [[FOR_BODY]]333; CHECK: for.end:334; CHECK-NEXT: ret i64 [[SUM]]335;336entry:337 %start = shl nuw i64 1, %a338 br label %for.body339 340for.body:341 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]342 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]343 %urem = urem i64 %size, %phi344 %add = add nsw i64 %sum, %urem345 %i = ashr i64 %phi, 2346 %icmp = icmp ugt i64 %i, 0347 br i1 %icmp, label %for.body, label %for.end348 349for.end:350 %r = phi i64 [ %sum, %for.body ]351 ret i64 %r352}353 354define i64 @known_power_of_two_urem_loop_negative(i64 %size, i64 %a) {355; Cannot deduce induction variable is a power of 2 if the recurrence is not one356; of the valid arithmetic operations.357;358; CHECK-LABEL: @known_power_of_two_urem_loop_negative(359; CHECK-NEXT: entry:360; CHECK-NEXT: [[START:%.*]] = shl nuw i64 1, [[A:%.*]]361; CHECK-NEXT: br label [[FOR_BODY:%.*]]362; CHECK: for.body:363; CHECK-NEXT: [[PHI:%.*]] = phi i64 [ [[START]], [[ENTRY:%.*]] ], [ [[I:%.*]], [[FOR_BODY]] ]364; CHECK-NEXT: [[SUM:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[ADD:%.*]], [[FOR_BODY]] ]365; CHECK-NEXT: [[UREM:%.*]] = urem i64 [[SIZE:%.*]], [[PHI]]366; CHECK-NEXT: [[ADD]] = add nuw i64 [[SUM]], [[UREM]]367; CHECK-NEXT: [[I]] = add nuw i64 [[PHI]], 1368; CHECK-NEXT: [[ICMP:%.*]] = icmp ugt i64 [[PHI]], 1369; CHECK-NEXT: br i1 [[ICMP]], label [[FOR_BODY]], label [[FOR_END:%.*]]370; CHECK: for.end:371; CHECK-NEXT: ret i64 [[SUM]]372;373entry:374 %start = shl nuw i64 1, %a375 br label %for.body376 377for.body:378 %phi = phi i64 [ %start, %entry ], [ %i, %for.body ]379 %sum = phi i64 [ 0, %entry ], [ %add, %for.body ]380 %urem = urem i64 %size, %phi381 %add = add nuw i64 %sum, %urem382 %i = add nuw i64 %phi, 1383 %icmp = icmp ugt i64 %i, 2384 br i1 %icmp, label %for.body, label %for.end385 386for.end:387 %r = phi i64 [ %sum, %for.body ]388 ret i64 %r389}390 391; https://alive2.llvm.org/ce/z/3QfEHm392define i8 @known_power_of_two_rust_next_power_of_two(i8 %x, i8 %y) {393; CHECK-LABEL: @known_power_of_two_rust_next_power_of_two(394; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[X:%.*]], -1395; CHECK-NEXT: [[TMP2:%.*]] = tail call range(i8 0, 9) i8 @llvm.ctlz.i8(i8 [[TMP1]], i1 true)396; CHECK-NEXT: [[TMP3:%.*]] = lshr i8 -1, [[TMP2]]397; CHECK-NEXT: [[TMP4:%.*]] = icmp ugt i8 [[X]], 1398; CHECK-NEXT: [[TMP5:%.*]] = select i1 [[TMP4]], i8 [[TMP3]], i8 0399; CHECK-NEXT: [[R:%.*]] = and i8 [[Y:%.*]], [[TMP5]]400; CHECK-NEXT: ret i8 [[R]]401;402 %2 = add i8 %x, -1403 %3 = tail call i8 @llvm.ctlz.i8(i8 %2, i1 true)404 %4 = lshr i8 -1, %3405 %5 = add i8 %4, 1406 %6 = icmp ugt i8 %x, 1407 %p = select i1 %6, i8 %5, i8 1408 ; Rust's implementation of `%p = next_power_of_two(%x)`409 410 %r = urem i8 %y, %p411 ret i8 %r412}413 414define i8 @known_power_of_two_lshr_add_one_allow_zero(i8 %x, i8 %y) {415; CHECK-LABEL: @known_power_of_two_lshr_add_one_allow_zero(416; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -1, [[X:%.*]]417; CHECK-NEXT: [[R:%.*]] = and i8 [[Y:%.*]], [[TMP1]]418; CHECK-NEXT: ret i8 [[R]]419;420 %4 = lshr i8 -1, %x421 %p = add i8 %4, 1422 423 ; Note: y % p --> y & (p - 1) allows p == 0424 %r = urem i8 %y, %p425 ret i8 %r426}427 428define i1 @known_power_of_two_lshr_add_one_nuw_deny_zero(i8 %x, i8 %y) {429; CHECK-LABEL: @known_power_of_two_lshr_add_one_nuw_deny_zero(430; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -1, [[X:%.*]]431; CHECK-NEXT: [[TMP2:%.*]] = sub i8 -2, [[TMP1]]432; CHECK-NEXT: [[TMP3:%.*]] = or i8 [[Y:%.*]], [[TMP2]]433; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[TMP3]], -1434; CHECK-NEXT: ret i1 [[R]]435;436 %4 = lshr i8 -1, %x437 %p = add nuw i8 %4, 1438 439 ; Note: A & B_Pow2 != B_Pow2 --> A & B_Pow2 == 0 requires B_Pow2 != 0440 %and = and i8 %p, %y441 %r = icmp ne i8 %and, %p442 ret i1 %r443}444 445define i1 @negative_known_power_of_two_lshr_add_one_deny_zero(i8 %x, i8 %y) {446; CHECK-LABEL: @negative_known_power_of_two_lshr_add_one_deny_zero(447; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -1, [[X:%.*]]448; CHECK-NEXT: [[TMP2:%.*]] = sub i8 -2, [[TMP1]]449; CHECK-NEXT: [[TMP3:%.*]] = or i8 [[Y:%.*]], [[TMP2]]450; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[TMP3]], -1451; CHECK-NEXT: ret i1 [[R]]452;453 %4 = lshr i8 -1, %x454 %p = add i8 %4, 1455 456 ; Note: A & B_Pow2 != B_Pow2 --> A & B_Pow2 == 0 requires B_Pow2 != 0457 %and = and i8 %p, %y458 %r = icmp ne i8 %and, %p459 ret i1 %r460}461 462define i1 @negative_known_power_of_two_lshr_add_one_nsw_deny_zero(i8 %x, i8 %y) {463; CHECK-LABEL: @negative_known_power_of_two_lshr_add_one_nsw_deny_zero(464; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -1, [[X:%.*]]465; CHECK-NEXT: [[TMP2:%.*]] = sub i8 -2, [[TMP1]]466; CHECK-NEXT: [[TMP3:%.*]] = or i8 [[Y:%.*]], [[TMP2]]467; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[TMP3]], -1468; CHECK-NEXT: ret i1 [[R]]469;470 %4 = lshr i8 -1, %x471 %p = add nsw i8 %4, 1472 473 ; Note: A & B_Pow2 != B_Pow2 --> A & B_Pow2 == 0 requires B_Pow2 != 0474 %and = and i8 %p, %y475 %r = icmp ne i8 %and, %p476 ret i1 %r477}478 479define i8 @known_power_of_two_lshr_add_negative_1(i8 %x, i8 %y) {480; CHECK-LABEL: @known_power_of_two_lshr_add_negative_1(481; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -2, [[X:%.*]]482; CHECK-NEXT: [[P:%.*]] = add nuw i8 [[TMP1]], 1483; CHECK-NEXT: [[R:%.*]] = urem i8 [[Y:%.*]], [[P]]484; CHECK-NEXT: ret i8 [[R]]485;486 %4 = lshr i8 -2, %x487 %p = add i8 %4, 1488 489 %r = urem i8 %y, %p490 ret i8 %r491}492 493define i8 @known_power_of_two_lshr_add_negative_2(i8 %x, i8 %y) {494; CHECK-LABEL: @known_power_of_two_lshr_add_negative_2(495; CHECK-NEXT: [[TMP1:%.*]] = lshr i8 -1, [[X:%.*]]496; CHECK-NEXT: [[P:%.*]] = add nsw i8 [[TMP1]], -1497; CHECK-NEXT: [[R:%.*]] = urem i8 [[Y:%.*]], [[P]]498; CHECK-NEXT: ret i8 [[R]]499;500 %4 = lshr i8 -1, %x501 %p = add i8 %4, -1502 503 %r = urem i8 %y, %p504 ret i8 %r505}506