1 ; RUN: opt < %s -S -indvars -loop-unroll | FileCheck %s 2 ; 3 ; PR15570: SEGV: SCEV back-edge info invalid after dead code removal. 4 ; 5 ; Indvars creates a SCEV expression for the loop's back edge taken 6 ; count, then determines that the comparison is always true and 7 ; removes it. 8 ; 9 ; When loop-unroll asks for the expression, it contains a NULL 10 ; SCEVUnknkown (as a CallbackVH). 11 ; 12 ; forgetMemoizedResults should invalidate the backedge taken count expression. 13 14 ; CHECK: @test 15 ; CHECK-NOT: phi 16 ; CHECK-NOT: icmp 17 ; CHECK: ret void 18 define void @test() { 19 entry: 20 %xor1 = xor i32 0, 1 21 br label %b17 22 23 b17: 24 br i1 undef, label %b22, label %b18 25 26 b18: 27 %phi1 = phi i32 [ %add1, %b18 ], [ %xor1, %b17 ] 28 %add1 = add nsw i32 %phi1, -1 29 %cmp1 = icmp sgt i32 %add1, 0 30 br i1 %cmp1, label %b18, label %b22 31 32 b22: 33 ret void 34 } 35
