| ; RUN: opt -S -loop-unswitch -instcombine -indvars < %s | FileCheck %s |
| |
| ; This used to crash in SCEVExpander when there were congruent phis with and |
| ; undef incoming value from the loop header. The -loop-unswitch -instcombine is |
| ; necessary to create just this pattern, which is essentially a nop and gets |
| ; folded away aggressively if spelled out in IR directly. |
| ; PR 20093 |
| |
| @c = external global i32**, align 8 |
| |
| define void @test1() { |
| entry: |
| br i1 undef, label %for.end12, label %for.cond.preheader |
| |
| for.cond.preheader: ; preds = %entry |
| %0 = load i32**, i32*** @c, align 8 |
| %1 = load i32*, i32** %0, align 8 |
| %2 = load i32, i32* %1, align 4 |
| br label %for.body |
| |
| for.body: ; preds = %for.cond.backedge, %for.body9.us, %for.cond.preheader |
| %3 = phi i32* [ %1, %for.cond.preheader ], [ %3, %for.cond.backedge ], [ %6, %for.body9.us ] |
| %4 = phi i32 [ %2, %for.cond.preheader ], [ undef, %for.cond.backedge ], [ %7, %for.body9.us ] |
| %i.024 = phi i32 [ 0, %for.cond.preheader ], [ %inc, %for.cond.backedge ], [ 0, %for.body9.us ] |
| %tobool1 = icmp eq i32 %4, 0 |
| br i1 %tobool1, label %if.end, label %for.cond.backedge |
| |
| if.end: ; preds = %for.body |
| %5 = load i32, i32* %3, align 4 |
| %tobool4 = icmp eq i32 %5, 0 |
| br i1 %tobool4, label %for.cond3, label %for.body9.preheader |
| |
| for.body9.preheader: ; preds = %if.end |
| %tobool8 = icmp eq i32 %i.024, 1 |
| br i1 %tobool8, label %for.body9.us, label %for.body9 |
| |
| for.body9.us: ; preds = %for.body9.preheader |
| %6 = load i32*, i32** undef, align 8 |
| %7 = load i32, i32* %6, align 4 |
| br label %for.body |
| |
| for.cond3: ; preds = %for.cond3, %if.end |
| br label %for.cond3 |
| |
| for.body9: ; preds = %for.body9, %for.body9.preheader |
| br label %for.body9 |
| |
| for.cond.backedge: ; preds = %for.body |
| %inc = add nsw i32 %i.024, 1 |
| br i1 false, label %for.body, label %for.end12 |
| |
| for.end12: ; preds = %for.cond.backedge, %entry |
| ret void |
| |
| ; CHECK-LABEL: @test1 |
| ; CHECK-NOT: phi |
| } |