1 ; RUN: opt -verify-loop-info -irce-print-changed-loops -irce -S < %s 2>&1 | FileCheck %s 2 ; RUN: opt -verify-loop-info -irce-print-changed-loops -passes='require<branch-prob>,loop(irce)' -S < %s 2>&1 | FileCheck %s 3 4 ; The test demonstrates that incorrect behavior of Clamp may lead to incorrect 5 ; calculation of post-loop exit condition. 6 7 ; CHECK-LABEL: irce: in function test_01: constrained Loop at depth 1 containing: %loop<header><exiting>,%in_bounds<exiting>,%not_zero<latch><exiting> 8 ; CHECK-NOT: irce: in function test_02: constrained Loop 9 10 define void @test_01() { 11 12 ; CHECK-LABEL: test_01 13 14 entry: 15 %indvars.iv.next467 = add nuw nsw i64 2, 1 16 %length.i167 = load i32, i32 addrspace(1)* undef, align 8 17 %tmp21 = zext i32 %length.i167 to i64 18 %tmp34 = load atomic i32, i32 addrspace(1)* undef unordered, align 4 19 %tmp35 = add i32 %tmp34, -9581 20 %tmp36 = icmp ugt i32 %length.i167, 1 21 br i1 %tmp36, label %preheader, label %exit 22 23 exit: ; preds = %in_bounds, %loop, %not_zero, %entry 24 ret void 25 26 preheader: ; preds = %entry 27 ; CHECK: preheader: 28 ; CHECK-NEXT: %length_gep.i146 = getelementptr inbounds i8, i8 addrspace(1)* undef, i64 8 29 ; CHECK-NEXT: %length_gep_typed.i147 = bitcast i8 addrspace(1)* undef to i32 addrspace(1)* 30 ; CHECK-NEXT: %tmp43 = icmp ult i64 %indvars.iv.next467, %tmp21 31 ; CHECK-NEXT: [[C0:%[^ ]+]] = icmp ugt i64 %tmp21, 1 32 ; CHECK-NEXT: %exit.mainloop.at = select i1 [[C0]], i64 %tmp21, i64 1 33 ; CHECK-NEXT: [[C1:%[^ ]+]] = icmp ult i64 1, %exit.mainloop.at 34 ; CHECK-NEXT: br i1 [[C1]], label %loop.preheader, label %main.pseudo.exit 35 36 %length_gep.i146 = getelementptr inbounds i8, i8 addrspace(1)* undef, i64 8 37 %length_gep_typed.i147 = bitcast i8 addrspace(1)* undef to i32 addrspace(1)* 38 %tmp43 = icmp ult i64 %indvars.iv.next467, %tmp21 39 br label %loop 40 41 not_zero: ; preds = %in_bounds 42 ; CHECK: not_zero: 43 ; CHECK: %tmp56 = icmp ult i64 %indvars.iv.next, %tmp21 44 ; CHECK-NEXT: [[COND:%[^ ]+]] = icmp ult i64 %indvars.iv.next, %exit.mainloop.at 45 ; CHECK-NEXT: br i1 [[COND]], label %loop, label %main.exit.selector 46 47 %tmp51 = trunc i64 %indvars.iv.next to i32 48 %tmp53 = mul i32 %tmp51, %tmp51 49 %tmp54 = add i32 %tmp53, -9582 50 %tmp55 = add i32 %tmp54, %tmp62 51 %tmp56 = icmp ult i64 %indvars.iv.next, %tmp21 52 br i1 %tmp56, label %loop, label %exit 53 54 loop: ; preds = %not_zero, %preheader 55 %tmp62 = phi i32 [ 1, %preheader ], [ %tmp55, %not_zero ] 56 %indvars.iv750 = phi i64 [ 1, %preheader ], [ %indvars.iv.next, %not_zero ] 57 %length.i148 = load i32, i32 addrspace(1)* %length_gep_typed.i147, align 8 58 %tmp68 = zext i32 %length.i148 to i64 59 %tmp97 = icmp ult i64 2, %tmp68 60 %or.cond = and i1 %tmp43, %tmp97 61 %tmp99 = icmp ult i64 %indvars.iv750, %tmp21 62 %or.cond1 = and i1 %or.cond, %tmp99 63 br i1 %or.cond1, label %in_bounds, label %exit 64 65 in_bounds: ; preds = %loop 66 %indvars.iv.next = add nuw nsw i64 %indvars.iv750, 3 67 %tmp107 = icmp ult i64 %indvars.iv.next, 2 68 br i1 %tmp107, label %not_zero, label %exit 69 } 70 71 define void @test_02() { 72 73 ; Now IRCE is smart enough to understand that the safe range here is empty. 74 ; Previously it executed the entire loop in safe preloop and never actually 75 ; entered the main loop. 76 77 entry: 78 br label %loop 79 80 loop: ; preds = %in_bounds, %entry 81 %iv1 = phi i64 [ 3, %entry ], [ %iv1.next, %in_bounds ] 82 %iv2 = phi i64 [ 4294967295, %entry ], [ %iv2.next, %in_bounds ] 83 %iv2.offset = add i64 %iv2, 1 84 %rc = icmp ult i64 %iv2.offset, 400 85 br i1 %rc, label %in_bounds, label %bci_321 86 87 bci_321: ; preds = %in_bounds, %loop 88 ret void 89 90 in_bounds: ; preds = %loop 91 %iv1.next = add nuw nsw i64 %iv1, 2 92 %iv2.next = add nuw nsw i64 %iv2, 2 93 %cond = icmp ugt i64 %iv1, 204 94 br i1 %cond, label %bci_321, label %loop 95 } 96
