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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt -S -passes=licm < %s | FileCheck %s --check-prefixes=CHECK,MT3; RUN: opt -S -passes=licm -licm-force-thread-model-single < %s | FileCheck %s --check-prefixes=CHECK,ST4 5@g = external global i326@c = external constant i327 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. See12; 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 417; 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]], 123; CHECK-NEXT: store i32 [[V_INC]], ptr @g, align 424; 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 void30;31entry:32 br label %loop33 34loop:35 br i1 %c, label %if, label %latch36 37if:38 %v = load i32, ptr @g39 %v.inc = add i32 %v, 140 store i32 %v.inc, ptr @g41 br label %latch42 43latch:44 br i1 %c2, label %exit, label %loop45 46exit:47 ret void48}49 50; The store can never be promoted here, because the global is constant, and51; 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 456; CHECK-NEXT: [[V_INC:%.*]] = add i32 [[V]], 157; 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 462; 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 void67;68entry:69 br label %loop70 71loop:72 br i1 %c, label %if, label %latch73 74if:75 %v = load i32, ptr @c76 %v.inc = add i32 %v, 177 store i32 %v.inc, ptr @c78 br label %latch79 80latch:81 br i1 %c2, label %exit, label %loop82 83exit:84 ret void85}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 the89; 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 494; 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]], 1100; CHECK-NEXT: store i32 [[V_INC]], ptr @g, align 4101; CHECK-NEXT: br label [[LATCH]]102; CHECK: else:103; CHECK-NEXT: store i32 42, ptr [[PTR:%.*]], align 4104; 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 void110;111entry:112 br label %loop113 114loop:115 br i1 %c, label %if, label %else116 117if:118 %v = load i32, ptr @g119 %v.inc = add i32 %v, 1120 store i32 %v.inc, ptr @g121 br label %latch122 123else:124 store i32 42, ptr %ptr125 br label %latch126 127latch:128 br i1 %c2, label %exit, label %loop129 130exit:131 ret void132}133 134; In single-thread mode both loads and stores can be promoted. In multi-thread135; mode only loads can be promoted, as a different thread might write to the136; 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 4141; MT-NEXT: call void @capture(ptr [[A]])142; MT-NEXT: [[A_PROMOTED:%.*]] = load i32, ptr [[A]], align 4143; 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]], 1149; MT-NEXT: store i32 [[V_INC]], ptr [[A]], align 4150; 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 void156;157; ST-LABEL: @promote_captured_alloca(158; ST-NEXT: entry:159; ST-NEXT: [[A:%.*]] = alloca i32, align 4160; ST-NEXT: call void @capture(ptr [[A]])161; ST-NEXT: [[A_PROMOTED:%.*]] = load i32, ptr [[A]], align 4162; 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]], 1168; 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 4175; ST-NEXT: ret void176;177entry:178 %a = alloca i32179 call void @capture(ptr %a)180 br label %loop181 182loop:183 br i1 %c, label %if, label %latch184 185if:186 %v = load i32, ptr %a187 %v.inc = add i32 %v, 1188 store i32 %v.inc, ptr %a189 br label %latch190 191latch:192 br i1 %c2, label %exit, label %loop193 194exit:195 ret void196}197 198; The store cannot be promoted here, because we do not know whether the199; 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 4204; 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]], 1210; CHECK-NEXT: store i32 [[V_INC]], ptr [[ARG]], align 4211; 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 void217;218entry:219 br label %loop220 221loop:222 br i1 %c, label %if, label %latch223 224if:225 %v = load i32, ptr %arg226 %v.inc = add i32 %v, 1227 store i32 %v.inc, ptr %arg228 br label %latch229 230latch:231 br i1 %c2, label %exit, label %loop232 233exit:234 ret void235}236