1; RUN: opt < %s -passes=indvars -S -o - | FileCheck %s 2 3; When eliminating the overflow intrinsic the indvars pass would incorrectly 4; return a false Modified status. This was caught by the pass return 5; status check that is hidden under EXPENSIVE_CHECKS. 6 7; CHECK-LABEL: for.body: 8; CHECK-NEXT: %0 = phi i16 [ %1, %for.body ], [ undef, %for.body.preheader ] 9; CHECK-NEXT: %1 = add nsw i16 %0, -1 10; CHECK-NEXT: %cmp = icmp sgt i16 %1, 0 11; CHECK-NEXT: call void @llvm.assume(i1 %cmp) 12 13; Function Attrs: nounwind 14define void @foo() #0 { 15entry: 16 %cmp1 = icmp sgt i16 undef, 0 17 br i1 %cmp1, label %for.body.preheader, label %for.end 18 19for.body.preheader: ; preds = %entry 20 br label %for.body 21 22for.body: ; preds = %for.body.preheader, %for.body 23 %0 = phi i16 [ %2, %for.body ], [ undef, %for.body.preheader ] 24 %1 = call { i16, i1 } @llvm.sadd.with.overflow.i16(i16 %0, i16 -1) 25 %2 = extractvalue { i16, i1 } %1, 0 26 %cmp = icmp sgt i16 %2, 0 27 call void @llvm.assume(i1 %cmp) 28 br label %for.body 29 30for.end: ; preds = %entry 31 ret void 32} 33 34; Function Attrs: nounwind readnone speculatable willreturn 35declare { i16, i1 } @llvm.sadd.with.overflow.i16(i16, i16) #1 36 37; Function Attrs: nounwind willreturn 38declare void @llvm.assume(i1) #2 39 40attributes #0 = { nounwind } 41attributes #1 = { nounwind readnone speculatable willreturn } 42attributes #2 = { nounwind willreturn } 43 44!llvm.ident = !{!0} 45 46!0 = !{!"clang version 12.0.0"} 47