1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt -S -passes=licm < %s | FileCheck %s --check-prefixes=CHECK,MT 3; RUN: opt -S -passes=licm -licm-force-thread-model-single < %s | FileCheck %s --check-prefixes=CHECK,ST 4 5@g = external global i32 6@c = external constant i32 7 8declare void @capture(ptr) 9 10; Even in single-thread mode, can only perform load-only promotion for globals, 11; because we might not have provenance to write to the global. See 12; promote_global_noalias for an example of the issue. 13define void @promote_global(i1 %c, i1 %c2) { 14; CHECK-LABEL: @promote_global( 15; CHECK-NEXT: entry: 16; CHECK-NEXT: [[G_PROMOTED:%.*]] = load i32, ptr @g, align 4 17; CHECK-NEXT: br label [[LOOP:%.*]] 18; CHECK: loop: 19; CHECK-NEXT: [[V_INC2:%.*]] = phi i32 [ [[V_INC1:%.*]], [[LATCH:%.*]] ], [ [[G_PROMOTED]], [[ENTRY:%.*]] ] 20; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[LATCH]] 21; CHECK: if: 22; CHECK-NEXT: [[V_INC:%.*]] = add i32 [[V_INC2]], 1 23; CHECK-NEXT: store i32 [[V_INC]], ptr @g, align 4 24; CHECK-NEXT: br label [[LATCH]] 25; CHECK: latch: 26; CHECK-NEXT: [[V_INC1]] = phi i32 [ [[V_INC]], [[IF]] ], [ [[V_INC2]], [[LOOP]] ] 27; CHECK-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 28; CHECK: exit: 29; CHECK-NEXT: ret void 30; 31entry: 32 br label %loop 33 34loop: 35 br i1 %c, label %if, label %latch 36 37if: 38 %v = load i32, ptr @g 39 %v.inc = add i32 %v, 1 40 store i32 %v.inc, ptr @g 41 br label %latch 42 43latch: 44 br i1 %c2, label %exit, label %loop 45 46exit: 47 ret void 48} 49 50; The store can never be promoted here, because the global is constant, and 51; the store could trap. 52define void @promote_constant_global(i1 %c, i1 %c2) { 53; CHECK-LABEL: @promote_constant_global( 54; CHECK-NEXT: entry: 55; CHECK-NEXT: [[V:%.*]] = load i32, ptr @c, align 4 56; CHECK-NEXT: [[V_INC:%.*]] = add i32 [[V]], 1 57; CHECK-NEXT: br label [[LOOP:%.*]] 58; CHECK: loop: 59; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[LATCH:%.*]] 60; CHECK: if: 61; CHECK-NEXT: store i32 [[V_INC]], ptr @c, align 4 62; CHECK-NEXT: br label [[LATCH]] 63; CHECK: latch: 64; CHECK-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 65; CHECK: exit: 66; CHECK-NEXT: ret void 67; 68entry: 69 br label %loop 70 71loop: 72 br i1 %c, label %if, label %latch 73 74if: 75 %v = load i32, ptr @c 76 %v.inc = add i32 %v, 1 77 store i32 %v.inc, ptr @c 78 br label %latch 79 80latch: 81 br i1 %c2, label %exit, label %loop 82 83exit: 84 ret void 85} 86 87; if %c is false and %ptr == @g, then this should store 42 to the pointer. 88; However, if we perform load+store promotion, then we would instead store the 89; original value of the global. 90define void @promote_global_noalias(i1 %c, i1 %c2, ptr noalias %ptr) { 91; CHECK-LABEL: @promote_global_noalias( 92; CHECK-NEXT: entry: 93; CHECK-NEXT: [[G_PROMOTED:%.*]] = load i32, ptr @g, align 4 94; CHECK-NEXT: br label [[LOOP:%.*]] 95; CHECK: loop: 96; CHECK-NEXT: [[V_INC2:%.*]] = phi i32 [ [[V_INC1:%.*]], [[LATCH:%.*]] ], [ [[G_PROMOTED]], [[ENTRY:%.*]] ] 97; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]] 98; CHECK: if: 99; CHECK-NEXT: [[V_INC:%.*]] = add i32 [[V_INC2]], 1 100; CHECK-NEXT: store i32 [[V_INC]], ptr @g, align 4 101; CHECK-NEXT: br label [[LATCH]] 102; CHECK: else: 103; CHECK-NEXT: store i32 42, ptr [[PTR:%.*]], align 4 104; CHECK-NEXT: br label [[LATCH]] 105; CHECK: latch: 106; CHECK-NEXT: [[V_INC1]] = phi i32 [ [[V_INC2]], [[ELSE]] ], [ [[V_INC]], [[IF]] ] 107; CHECK-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 108; CHECK: exit: 109; CHECK-NEXT: ret void 110; 111entry: 112 br label %loop 113 114loop: 115 br i1 %c, label %if, label %else 116 117if: 118 %v = load i32, ptr @g 119 %v.inc = add i32 %v, 1 120 store i32 %v.inc, ptr @g 121 br label %latch 122 123else: 124 store i32 42, ptr %ptr 125 br label %latch 126 127latch: 128 br i1 %c2, label %exit, label %loop 129 130exit: 131 ret void 132} 133 134; In single-thread mode both loads and stores can be promoted. In multi-thread 135; mode only loads can be promoted, as a different thread might write to the 136; captured alloca. 137define void @promote_captured_alloca(i1 %c, i1 %c2) { 138; MT-LABEL: @promote_captured_alloca( 139; MT-NEXT: entry: 140; MT-NEXT: [[A:%.*]] = alloca i32, align 4 141; MT-NEXT: call void @capture(ptr [[A]]) 142; MT-NEXT: [[A_PROMOTED:%.*]] = load i32, ptr [[A]], align 4 143; MT-NEXT: br label [[LOOP:%.*]] 144; MT: loop: 145; MT-NEXT: [[V_INC2:%.*]] = phi i32 [ [[V_INC1:%.*]], [[LATCH:%.*]] ], [ [[A_PROMOTED]], [[ENTRY:%.*]] ] 146; MT-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[LATCH]] 147; MT: if: 148; MT-NEXT: [[V_INC:%.*]] = add i32 [[V_INC2]], 1 149; MT-NEXT: store i32 [[V_INC]], ptr [[A]], align 4 150; MT-NEXT: br label [[LATCH]] 151; MT: latch: 152; MT-NEXT: [[V_INC1]] = phi i32 [ [[V_INC]], [[IF]] ], [ [[V_INC2]], [[LOOP]] ] 153; MT-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 154; MT: exit: 155; MT-NEXT: ret void 156; 157; ST-LABEL: @promote_captured_alloca( 158; ST-NEXT: entry: 159; ST-NEXT: [[A:%.*]] = alloca i32, align 4 160; ST-NEXT: call void @capture(ptr [[A]]) 161; ST-NEXT: [[A_PROMOTED:%.*]] = load i32, ptr [[A]], align 4 162; ST-NEXT: br label [[LOOP:%.*]] 163; ST: loop: 164; ST-NEXT: [[V_INC2:%.*]] = phi i32 [ [[V_INC1:%.*]], [[LATCH:%.*]] ], [ [[A_PROMOTED]], [[ENTRY:%.*]] ] 165; ST-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[LATCH]] 166; ST: if: 167; ST-NEXT: [[V_INC:%.*]] = add i32 [[V_INC2]], 1 168; ST-NEXT: br label [[LATCH]] 169; ST: latch: 170; ST-NEXT: [[V_INC1]] = phi i32 [ [[V_INC]], [[IF]] ], [ [[V_INC2]], [[LOOP]] ] 171; ST-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 172; ST: exit: 173; ST-NEXT: [[V_INC1_LCSSA:%.*]] = phi i32 [ [[V_INC1]], [[LATCH]] ] 174; ST-NEXT: store i32 [[V_INC1_LCSSA]], ptr [[A]], align 4 175; ST-NEXT: ret void 176; 177entry: 178 %a = alloca i32 179 call void @capture(ptr %a) 180 br label %loop 181 182loop: 183 br i1 %c, label %if, label %latch 184 185if: 186 %v = load i32, ptr %a 187 %v.inc = add i32 %v, 1 188 store i32 %v.inc, ptr %a 189 br label %latch 190 191latch: 192 br i1 %c2, label %exit, label %loop 193 194exit: 195 ret void 196} 197 198; The store cannot be promoted here, because we do not know whether the 199; argument memory is writable. 200define void @promote_arg(ptr noalias dereferenceable(4) align 4 %arg, i1 %c, i1 %c2) { 201; CHECK-LABEL: @promote_arg( 202; CHECK-NEXT: entry: 203; CHECK-NEXT: [[ARG_PROMOTED:%.*]] = load i32, ptr [[ARG:%.*]], align 4 204; CHECK-NEXT: br label [[LOOP:%.*]] 205; CHECK: loop: 206; CHECK-NEXT: [[V_INC2:%.*]] = phi i32 [ [[V_INC1:%.*]], [[LATCH:%.*]] ], [ [[ARG_PROMOTED]], [[ENTRY:%.*]] ] 207; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[LATCH]] 208; CHECK: if: 209; CHECK-NEXT: [[V_INC:%.*]] = add i32 [[V_INC2]], 1 210; CHECK-NEXT: store i32 [[V_INC]], ptr [[ARG]], align 4 211; CHECK-NEXT: br label [[LATCH]] 212; CHECK: latch: 213; CHECK-NEXT: [[V_INC1]] = phi i32 [ [[V_INC]], [[IF]] ], [ [[V_INC2]], [[LOOP]] ] 214; CHECK-NEXT: br i1 [[C2:%.*]], label [[EXIT:%.*]], label [[LOOP]] 215; CHECK: exit: 216; CHECK-NEXT: ret void 217; 218entry: 219 br label %loop 220 221loop: 222 br i1 %c, label %if, label %latch 223 224if: 225 %v = load i32, ptr %arg 226 %v.inc = add i32 %v, 1 227 store i32 %v.inc, ptr %arg 228 br label %latch 229 230latch: 231 br i1 %c2, label %exit, label %loop 232 233exit: 234 ret void 235} 236