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1; RUN: opt < %s -passes=lcssa,loop-simplify,indvars -S | FileCheck %s2target triple = "x86_64-unknown-linux-gnu"3 4; PR28272, PR288255; When LoopSimplify separates nested loops, it might break LCSSA form: values6; from the original loop might be used in the outer loop. This test invokes7; loop-unroll, which calls loop-simplify before itself. If LCSSA is broken8; after loop-simplify, we crash on assertion.9 10; CHECK-LABEL: @foo11define void @foo(i1 %arg) {12entry:13 br label %header14 15header:16 br label %loop117 18loop1:19 br i1 true, label %loop1, label %bb4320 21bb43:22 %a = phi i32 [ undef, %loop1 ], [ 0, %bb45 ], [ %a, %bb54 ]23 %b = phi i32 [ 0, %loop1 ], [ 1, %bb54 ], [ %c, %bb45 ]24 br i1 true, label %bb114, label %header25 26bb114:27 %c = add i32 0, 128 %d = add i32 0, 129 br i1 true, label %bb45, label %bb5430 31bb45:32 %x = add i32 %d, 033 br label %bb4334 35bb54:36 br label %bb4337}38 39; CHECK-LABEL: @foo240define void @foo2(i1 %arg) {41entry:42 br label %outer43 44outer.loopexit:45 br label %outer46 47outer:48 br label %loop149 50loop1:51 br i1 true, label %loop1, label %loop2.preheader52 53loop2.preheader:54 %a.ph = phi i32 [ undef, %loop1 ]55 %b.ph = phi i32 [ 0, %loop1 ]56 br label %loop257 58loop2:59 %a = phi i32 [ 0, %loop2.if.true ], [ %a, %loop2.if.false ], [ %a.ph, %loop2.preheader ], [0, %bb]60 %b = phi i32 [ 1, %loop2.if.false ], [ %c, %loop2.if.true ], [ %b.ph, %loop2.preheader ], [%c, %bb]61 br i1 true, label %loop2.if, label %outer.loopexit62 63loop2.if:64 %c = add i32 0, 165 switch i32 undef, label %loop2.if.false [i32 0, label %loop2.if.true66 i32 1, label %bb]67 68loop2.if.true:69 br i1 %arg, label %loop2, label %bb70 71loop2.if.false:72 br label %loop273 74bb:75 br label %loop276}77 78; When LoopSimplify separates nested loops, it might break LCSSA form: values79; from the original loop might be used in exit blocks of the outer loop.80; CHECK-LABEL: @foo381define void @foo3(i1 %arg) {82entry:83 br label %bb184 85bb1:86 br i1 %arg, label %bb2, label %bb187 88bb2:89 %a = phi i32 [ undef, %bb1 ], [ %a, %bb3 ], [ undef, %bb5 ]90 br i1 %arg, label %bb3, label %bb191 92bb3:93 %b = load ptr, ptr undef94 br i1 %arg, label %bb2, label %bb495 96bb4:97 br i1 %arg, label %bb5, label %bb698 99bb5:100 br i1 %arg, label %bb2, label %bb4101 102bb6:103 br i1 %arg, label %bb_end, label %bb1104 105bb_end:106 %x = getelementptr i32, ptr %b107 br label %bb_end108}109 110; When LoopSimplify separates nested loops, it might break LCSSA form: values111; from the original loop might occur in a loop, which is now a sibling of the112; original loop (before separating it was a subloop of the original loop, and113; thus didn't require an lcssa phi nodes).114; CHECK-LABEL: @foo4115define void @foo4(i1 %arg) {116bb1:117 br label %bb2118 119; CHECK: bb2.loopexit:120bb2.loopexit: ; preds = %bb3121 %i.ph = phi i32 [ 0, %bb3 ]122 br label %bb2123 124; CHECK: bb2.outer:125; CHECK: bb2:126bb2: ; preds = %bb2.loopexit, %bb2, %bb1127 %i = phi i32 [ 0, %bb1 ], [ %i, %bb2 ], [ %i.ph, %bb2.loopexit ]128 %x = load i32, ptr undef, align 8129 br i1 %arg, label %bb2, label %bb3.preheader130 131; CHECK: bb3.preheader:132bb3.preheader: ; preds = %bb2133; CHECK: %x.lcssa = phi i32 [ %x, %bb2 ]134 br label %bb3135 136bb3: ; preds = %bb3.preheader, %bb3137 %y = add i32 2, %x138 br i1 true, label %bb2.loopexit, label %bb3139}140