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1; RUN: llc < %s -mtriple=arm-apple-darwin -relocation-model=dynamic-no-pic -mcpu=cortex-a8 -asm-verbose=false | FileCheck %s2 3declare void @bar(i32)4declare void @car(i32)5declare void @dar(i32)6declare void @ear(i32)7declare void @far(i32)8declare i1 @qux()9 10@GHJK = global i32 011 12declare ptr @choose(ptr, ptr)13 14; BranchFolding should tail-duplicate the indirect jump to avoid15; redundant branching.16 17; CHECK-LABEL: tail_duplicate_me:18; CHECK: qux19; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK20; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK21; CHECK: str r22; CHECK-NEXT: bx r23; CHECK: qux24; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK25; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK26; CHECK: str r27; CHECK-NEXT: bx r28; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK29; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK30; CHECK: str r31; CHECK-NEXT: bx r32 33define void @tail_duplicate_me() nounwind {34entry:35 %a = call i1 @qux()36 %c = call ptr @choose(ptr blockaddress(@tail_duplicate_me, %return),37 ptr blockaddress(@tail_duplicate_me, %altret))38 br i1 %a, label %A, label %next39next:40 %b = call i1 @qux()41 br i1 %b, label %B, label %C42 43A:44 call void @bar(i32 0)45 store i32 0, ptr @GHJK46 br label %M47 48B:49 call void @car(i32 1)50 store i32 0, ptr @GHJK51 br label %M52 53C:54 call void @dar(i32 2)55 store i32 0, ptr @GHJK56 br label %M57 58M:59 indirectbr ptr %c, [label %return, label %altret]60 61return:62 call void @ear(i32 1000)63 ret void64altret:65 call void @far(i32 1001)66 ret void67}68 69; Use alternating abort functions so that the blocks we wish to merge are not70; layout successors during branch folding.71 72; CHECK-LABEL: merge_alternating_aborts:73; CHECK-NOT: _abort74; CHECK-NOT: _alt_abort75; CHECK: bxne lr76; CHECK-NOT: _abort77; CHECK-NOT: _alt_abort78; CHECK: LBB{{.*}}:79; CHECK: mov lr, pc80; CHECK: b _alt_abort81; CHECK-NOT: _abort82; CHECK-NOT: _alt_abort83; CHECK: LBB{{.*}}:84; CHECK: mov lr, pc85; CHECK: b _abort86; CHECK-NOT: _abort87; CHECK-NOT: _alt_abort88 89declare void @abort()90declare void @alt_abort()91 92define void @merge_alternating_aborts() {93entry:94 %c1 = call i1 @qux()95 br i1 %c1, label %cont1, label %abort196abort1:97 call void @abort()98 unreachable99cont1:100 %c2 = call i1 @qux()101 br i1 %c2, label %cont2, label %abort2102abort2:103 call void @alt_abort()104 unreachable105cont2:106 %c3 = call i1 @qux()107 br i1 %c3, label %cont3, label %abort3108abort3:109 call void @abort()110 unreachable111cont3:112 %c4 = call i1 @qux()113 br i1 %c4, label %cont4, label %abort4114abort4:115 call void @alt_abort()116 unreachable117cont4:118 ret void119}120