1 ; RUN: opt < %s -licm -S | FileCheck %s 2 3 @X = global i32 0 ; <i32*> [#uses=1] 4 5 declare void @foo() 6 7 ; This testcase tests for a problem where LICM hoists 8 ; potentially trapping instructions when they are not guaranteed to execute. 9 define i32 @test1(i1 %c) { 10 ; CHECK-LABEL: @test1( 11 %A = load i32, i32* @X ; <i32> [#uses=2] 12 br label %Loop 13 Loop: ; preds = %LoopTail, %0 14 call void @foo( ) 15 br i1 %c, label %LoopTail, label %IfUnEqual 16 17 IfUnEqual: ; preds = %Loop 18 ; CHECK: IfUnEqual: 19 ; CHECK-NEXT: sdiv i32 4, %A 20 %B1 = sdiv i32 4, %A ; <i32> [#uses=1] 21 br label %LoopTail 22 23 LoopTail: ; preds = %IfUnEqual, %Loop 24 %B = phi i32 [ 0, %Loop ], [ %B1, %IfUnEqual ] ; <i32> [#uses=1] 25 br i1 %c, label %Loop, label %Out 26 Out: ; preds = %LoopTail 27 %C = sub i32 %A, %B ; <i32> [#uses=1] 28 ret i32 %C 29 } 30 31 32 declare void @foo2(i32) nounwind 33 34 35 ;; It is ok and desirable to hoist this potentially trapping instruction. 36 define i32 @test2(i1 %c) { 37 ; CHECK-LABEL: @test2( 38 ; CHECK-NEXT: load i32, i32* @X 39 ; CHECK-NEXT: %B = sdiv i32 4, %A 40 %A = load i32, i32* @X ; <i32> [#uses=2] 41 br label %Loop 42 Loop: 43 ;; Should have hoisted this div! 44 %B = sdiv i32 4, %A ; <i32> [#uses=2] 45 call void @foo2( i32 %B ) 46 br i1 %c, label %Loop, label %Out 47 Out: ; preds = %Loop 48 %C = sub i32 %A, %B ; <i32> [#uses=1] 49 ret i32 %C 50 } 51 52 53 ; This loop invariant instruction should be constant folded, not hoisted. 54 define i32 @test3(i1 %c) { 55 ; CHECK-LABEL: define i32 @test3( 56 ; CHECK: call void @foo2(i32 6) 57 %A = load i32, i32* @X ; <i32> [#uses=2] 58 br label %Loop 59 Loop: 60 %B = add i32 4, 2 ; <i32> [#uses=2] 61 call void @foo2( i32 %B ) 62 br i1 %c, label %Loop, label %Out 63 Out: ; preds = %Loop 64 %C = sub i32 %A, %B ; <i32> [#uses=1] 65 ret i32 %C 66 } 67 68 ; CHECK-LABEL: @test4( 69 ; CHECK: call 70 ; CHECK: sdiv 71 ; CHECK: ret 72 define i32 @test4(i32 %x, i32 %y) nounwind uwtable ssp { 73 entry: 74 br label %for.body 75 76 for.body: ; preds = %entry, %for.body 77 %i.02 = phi i32 [ 0, %entry ], [ %inc, %for.body ] 78 %n.01 = phi i32 [ 0, %entry ], [ %add, %for.body ] 79 call void @foo_may_call_exit(i32 0) 80 %div = sdiv i32 %x, %y 81 %add = add nsw i32 %n.01, %div 82 %inc = add nsw i32 %i.02, 1 83 %cmp = icmp slt i32 %inc, 10000 84 br i1 %cmp, label %for.body, label %for.end 85 86 for.end: ; preds = %for.body 87 %n.0.lcssa = phi i32 [ %add, %for.body ] 88 ret i32 %n.0.lcssa 89 } 90 91 declare void @foo_may_call_exit(i32) 92 93 ; PR14854 94 ; CHECK-LABEL: @test5( 95 ; CHECK: extractvalue 96 ; CHECK: br label %tailrecurse 97 ; CHECK: tailrecurse: 98 ; CHECK: ifend: 99 ; CHECK: insertvalue 100 define { i32*, i32 } @test5(i32 %i, { i32*, i32 } %e) { 101 entry: 102 br label %tailrecurse 103 104 tailrecurse: ; preds = %then, %entry 105 %i.tr = phi i32 [ %i, %entry ], [ %cmp2, %then ] 106 %out = extractvalue { i32*, i32 } %e, 1 107 %d = insertvalue { i32*, i32 } %e, i32* null, 0 108 %cmp1 = icmp sgt i32 %out, %i.tr 109 br i1 %cmp1, label %then, label %ifend 110 111 then: ; preds = %tailrecurse 112 call void @foo() 113 %cmp2 = add i32 %i.tr, 1 114 br label %tailrecurse 115 116 ifend: ; preds = %tailrecurse 117 ret { i32*, i32 } %d 118 } 119
