1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3 2; RUN: opt -S -loop-predication-skip-profitability-checks=false -passes='require<scalar-evolution>,loop-mssa(loop-predication)' %s | FileCheck %s 3 4target triple = "x86_64-unknown-linux-gnu" 5 6; Function Attrs: nocallback nofree nosync willreturn 7declare void @llvm.experimental.guard(i1, ...) #0 8 9; Check that LoopPredication doesn't crash on all-zero branch weights 10define void @foo() { 11; CHECK-LABEL: define void @foo() { 12; CHECK-NEXT: entry: 13; CHECK-NEXT: br label [[HEADER:%.*]] 14; CHECK: Header: 15; CHECK-NEXT: [[J2:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[J_NEXT:%.*]], [[LATCH:%.*]] ] 16; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 false, i32 0) [ "deopt"() ] 17; CHECK-NEXT: [[J_NEXT]] = add i64 [[J2]], 1 18; CHECK-NEXT: br i1 false, label [[LATCH]], label [[EXIT:%.*]] 19; CHECK: Latch: 20; CHECK-NEXT: [[SPECULATE_TRIP_COUNT:%.*]] = icmp ult i64 [[J2]], 0 21; CHECK-NEXT: br i1 [[SPECULATE_TRIP_COUNT]], label [[HEADER]], label [[COMMON_RET_LOOPEXIT:%.*]], !prof [[PROF0:![0-9]+]] 22; CHECK: common.ret.loopexit: 23; CHECK-NEXT: br label [[COMMON_RET:%.*]] 24; CHECK: common.ret: 25; CHECK-NEXT: ret void 26; CHECK: exit: 27; CHECK-NEXT: br label [[COMMON_RET]] 28; 29entry: 30 br label %Header 31 32Header: ; preds = %Latch, %entry 33 %j2 = phi i64 [ 0, %entry ], [ %j.next, %Latch ] 34 call void (i1, ...) @llvm.experimental.guard(i1 false, i32 0) [ "deopt"() ] 35 %j.next = add i64 %j2, 1 36 br i1 false, label %Latch, label %exit 37 38Latch: ; preds = %Header 39 %speculate_trip_count = icmp ult i64 %j2, 0 40 br i1 %speculate_trip_count, label %Header, label %common.ret, !prof !0 41 42common.ret: ; preds = %exit, %Latch 43 ret void 44 45exit: ; preds = %Header 46 br label %common.ret 47} 48 49attributes #0 = { nocallback nofree nosync willreturn } 50 51!0 = !{!"branch_weights", i32 0, i32 0} 52