1 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2 ; RUN: opt -S %s -passes=loop-instsimplify | FileCheck %s 3 4 ; Test very basic folding and propagation occurs within a loop body. This should 5 ; collapse to the loop iteration structure and the LCSSA PHI node. 6 define i32 @test1(i32 %n, i32 %x) { 7 ; CHECK-LABEL: @test1( 8 ; CHECK-NEXT: entry: 9 ; CHECK-NEXT: br label [[LOOP:%.*]] 10 ; CHECK: loop: 11 ; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] 12 ; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1 13 ; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]] 14 ; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]] 15 ; CHECK: exit: 16 ; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP]] ] 17 ; CHECK-NEXT: ret i32 [[X_LCSSA]] 18 ; 19 entry: 20 br label %loop 21 22 loop: 23 %i = phi i32 [ 0, %entry ], [ %i.next, %loop ] 24 %x.add = add nsw i32 %x, 0 25 %x.sub = sub i32 %x.add, 0 26 %x.and = and i32 %x.sub, -1 27 %i.next = add nsw i32 %i, 1 28 %i.cmp = icmp slt i32 %i.next, %n 29 br i1 %i.cmp, label %loop, label %exit 30 31 exit: 32 %x.lcssa = phi i32 [ %x.and, %loop ] 33 ret i32 %x.lcssa 34 } 35 36 ; Test basic loop structure that still has a simplification feed a prior PHI. 37 define i32 @test2(i32 %n, i32 %x) { 38 ; CHECK-LABEL: @test2( 39 ; CHECK-NEXT: entry: 40 ; CHECK-NEXT: br label [[LOOP:%.*]] 41 ; CHECK: loop: 42 ; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] 43 ; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1 44 ; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]] 45 ; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]] 46 ; CHECK: exit: 47 ; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP]] ] 48 ; CHECK-NEXT: ret i32 [[X_LCSSA]] 49 ; 50 entry: 51 br label %loop 52 53 loop: 54 %i = phi i32 [ 0, %entry ], [ %i.next, %loop ] 55 %x.loop = phi i32 [ %x, %entry ], [ %x.next, %loop ] 56 %x.next = add nsw i32 %x.loop, 0 57 %i.next = add nsw i32 %i, 1 58 %i.cmp = icmp slt i32 %i.next, %n 59 br i1 %i.cmp, label %loop, label %exit 60 61 exit: 62 %x.lcssa = phi i32 [ %x.loop, %loop ] 63 ret i32 %x.lcssa 64 } 65 66 ; Test a diamond CFG with inner PHI nodes. 67 define i32 @test3(i32 %n, i32 %x) { 68 ; CHECK-LABEL: @test3( 69 ; CHECK-NEXT: entry: 70 ; CHECK-NEXT: br label [[LOOP:%.*]] 71 ; CHECK: loop: 72 ; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] 73 ; CHECK-NEXT: [[X_CMP:%.*]] = icmp slt i32 [[I]], 42 74 ; CHECK-NEXT: br i1 [[X_CMP]], label [[LOOP_LHS:%.*]], label [[LOOP_RHS:%.*]] 75 ; CHECK: loop.lhs: 76 ; CHECK-NEXT: br label [[LOOP_LATCH]] 77 ; CHECK: loop.rhs: 78 ; CHECK-NEXT: br label [[LOOP_LATCH]] 79 ; CHECK: loop.latch: 80 ; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1 81 ; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]] 82 ; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]] 83 ; CHECK: exit: 84 ; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP_LATCH]] ] 85 ; CHECK-NEXT: ret i32 [[X_LCSSA]] 86 ; 87 entry: 88 br label %loop 89 90 loop: 91 %i = phi i32 [ 0, %entry ], [ %i.next, %loop.latch ] 92 %x.loop = phi i32 [ %x, %entry ], [ %x.phi, %loop.latch ] 93 %x.add = add nsw i32 %x.loop, 0 94 %x.cmp = icmp slt i32 %i, 42 95 br i1 %x.cmp, label %loop.lhs, label %loop.rhs 96 97 loop.lhs: 98 %x.l.add = add nsw i32 %x.add, 0 99 br label %loop.latch 100 101 loop.rhs: 102 %x.r.sub = sub nsw i32 %x.add, 0 103 br label %loop.latch 104 105 loop.latch: 106 %x.phi = phi i32 [ %x.l.add, %loop.lhs ], [ %x.r.sub, %loop.rhs ] 107 %i.next = add nsw i32 %i, 1 108 %i.cmp = icmp slt i32 %i.next, %n 109 br i1 %i.cmp, label %loop, label %exit 110 111 exit: 112 %x.lcssa = phi i32 [ %x.loop, %loop.latch ] 113 ret i32 %x.lcssa 114 } 115 116 ; Test an inner loop that is only simplified when processing the outer loop, and 117 ; an outer loop only simplified when processing the inner loop. 118 define i32 @test4(i32 %n, i32 %m, i32 %x) { 119 ; CHECK-LABEL: @test4( 120 ; CHECK-NEXT: entry: 121 ; CHECK-NEXT: br label [[LOOP:%.*]] 122 ; CHECK: loop: 123 ; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP_LATCH:%.*]] ] 124 ; CHECK-NEXT: br label [[LOOP_INNER:%.*]] 125 ; CHECK: loop.inner: 126 ; CHECK-NEXT: [[J:%.*]] = phi i32 [ 0, [[LOOP]] ], [ [[J_NEXT:%.*]], [[LOOP_INNER]] ] 127 ; CHECK-NEXT: [[J_NEXT]] = add nsw i32 [[J]], 1 128 ; CHECK-NEXT: [[J_CMP:%.*]] = icmp slt i32 [[J_NEXT]], [[M:%.*]] 129 ; CHECK-NEXT: br i1 [[J_CMP]], label [[LOOP_INNER]], label [[LOOP_LATCH]] 130 ; CHECK: loop.latch: 131 ; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1 132 ; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]] 133 ; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]] 134 ; CHECK: exit: 135 ; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP_LATCH]] ] 136 ; CHECK-NEXT: ret i32 [[X_LCSSA]] 137 ; 138 entry: 139 br label %loop 140 141 loop: 142 %i = phi i32 [ 0, %entry ], [ %i.next, %loop.latch ] 143 %x.loop = phi i32 [ %x, %entry ], [ %x.inner.lcssa, %loop.latch ] 144 %x.add = add nsw i32 %x.loop, 0 145 br label %loop.inner 146 147 loop.inner: 148 %j = phi i32 [ 0, %loop ], [ %j.next, %loop.inner ] 149 %x.inner.loop = phi i32 [ %x.add, %loop ], [ %x.inner.add, %loop.inner ] 150 %x.inner.add = add nsw i32 %x.inner.loop, 0 151 %j.next = add nsw i32 %j, 1 152 %j.cmp = icmp slt i32 %j.next, %m 153 br i1 %j.cmp, label %loop.inner, label %loop.latch 154 155 loop.latch: 156 %x.inner.lcssa = phi i32 [ %x.inner.loop, %loop.inner ] 157 %i.next = add nsw i32 %i, 1 158 %i.cmp = icmp slt i32 %i.next, %n 159 br i1 %i.cmp, label %loop, label %exit 160 161 exit: 162 %x.lcssa = phi i32 [ %x.loop, %loop.latch ] 163 ret i32 %x.lcssa 164 } 165
