; RUN: opt < %s -indvars -S | FileCheck %s ; This is regression test for the bug in ScalarEvolution::isKnownPredicate. ; It does not check whether SCEV is available at loop entry before invoking ; and utility function isLoopEntryGuardedByCond and that leads to miscompile. target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1" target triple = "x86_64-unknown-linux-gnu" declare void @foo(i64) declare void @bar(i32) define void @test(i8* %arr) { entry: br label %outer_header outer_header: %i = phi i32 [40, %entry], [%i.next, %outer_latch] %i.64 = sext i32 %i to i64 br label %inner_header inner_header: %j = phi i32 [27, %outer_header], [%j.next, %inner_backedge] %j1 = zext i32 %j to i64 ; The next 4 lines are required for avoid widening of %j and ; SCEV at %cmp would not be AddRec. %gep = getelementptr inbounds i8, i8* %arr, i64 %j1 %ld = load i8, i8* %gep %ec = icmp eq i8 %ld, 0 br i1 %ec, label %return, label %inner_backedge inner_backedge: %cmp = icmp ult i32 %j, %i %s = select i1 %cmp, i32 %i, i32 %j ; Select should not be simplified because if ; %i == 26 and %j == 27, %s should be equal to %j. ; In case of a bug the instruction is simplified to ; %s = select i1 true, i32 %0, i32 %j ; CHECK-NOT: %s = select i1 true call void @bar(i32 %s) %j.next = add nsw i32 %j, -2 %cond = icmp ult i32 %j, 3 br i1 %cond, label %outer_latch, label %inner_header outer_latch: %i.next = add i32 %i, -1 %cond2 = icmp sgt i32 %i.next, 13 ; This line is just for forcing widening of %i call void @foo(i64 %i.64) br i1 %cond2, label %outer_header, label %return return: ret void }