1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt -codegenprepare -S < %s | FileCheck %s 3 4target triple = "x86_64-unknown-unknown" 5 6; Nothing to sink and convert here. 7 8define i32 @no_sink(double %a, double* %b, i32 %x, i32 %y) { 9; CHECK-LABEL: @no_sink( 10; CHECK-NEXT: entry: 11; CHECK-NEXT: [[LOAD:%.*]] = load double, double* [[B:%.*]], align 8 12; CHECK-NEXT: [[CMP:%.*]] = fcmp olt double [[LOAD]], [[A:%.*]] 13; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 [[X:%.*]], i32 [[Y:%.*]] 14; CHECK-NEXT: ret i32 [[SEL]] 15; 16entry: 17 %load = load double, double* %b, align 8 18 %cmp = fcmp olt double %load, %a 19 %sel = select i1 %cmp, i32 %x, i32 %y 20 ret i32 %sel 21} 22 23 24; An 'fdiv' is expensive, so sink it rather than speculatively execute it. 25 26define float @fdiv_true_sink(float %a, float %b) { 27; CHECK-LABEL: @fdiv_true_sink( 28; CHECK-NEXT: entry: 29; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 1.000000e+00 30; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_TRUE_SINK:%.*]], label [[SELECT_END:%.*]] 31; CHECK: select.true.sink: 32; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 33; CHECK-NEXT: br label [[SELECT_END]] 34; CHECK: select.end: 35; CHECK-NEXT: [[SEL:%.*]] = phi float [ [[DIV]], [[SELECT_TRUE_SINK]] ], [ 2.000000e+00, [[ENTRY:%.*]] ] 36; CHECK-NEXT: ret float [[SEL]] 37; 38entry: 39 %div = fdiv float %a, %b 40 %cmp = fcmp ogt float %a, 1.0 41 %sel = select i1 %cmp, float %div, float 2.0 42 ret float %sel 43} 44 45define float @fdiv_false_sink(float %a, float %b) { 46; CHECK-LABEL: @fdiv_false_sink( 47; CHECK-NEXT: entry: 48; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 3.000000e+00 49; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_END:%.*]], label [[SELECT_FALSE_SINK:%.*]] 50; CHECK: select.false.sink: 51; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 52; CHECK-NEXT: br label [[SELECT_END]] 53; CHECK: select.end: 54; CHECK-NEXT: [[SEL:%.*]] = phi float [ 4.000000e+00, [[ENTRY:%.*]] ], [ [[DIV]], [[SELECT_FALSE_SINK]] ] 55; CHECK-NEXT: ret float [[SEL]] 56; 57entry: 58 %div = fdiv float %a, %b 59 %cmp = fcmp ogt float %a, 3.0 60 %sel = select i1 %cmp, float 4.0, float %div 61 ret float %sel 62} 63 64define float @fdiv_both_sink(float %a, float %b) { 65; CHECK-LABEL: @fdiv_both_sink( 66; CHECK-NEXT: entry: 67; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 5.000000e+00 68; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_TRUE_SINK:%.*]], label [[SELECT_FALSE_SINK:%.*]] 69; CHECK: select.true.sink: 70; CHECK-NEXT: [[DIV1:%.*]] = fdiv float [[A]], [[B:%.*]] 71; CHECK-NEXT: br label [[SELECT_END:%.*]] 72; CHECK: select.false.sink: 73; CHECK-NEXT: [[DIV2:%.*]] = fdiv float [[B]], [[A]] 74; CHECK-NEXT: br label [[SELECT_END]] 75; CHECK: select.end: 76; CHECK-NEXT: [[SEL:%.*]] = phi float [ [[DIV1]], [[SELECT_TRUE_SINK]] ], [ [[DIV2]], [[SELECT_FALSE_SINK]] ] 77; CHECK-NEXT: ret float [[SEL]] 78; 79entry: 80 %div1 = fdiv float %a, %b 81 %div2 = fdiv float %b, %a 82 %cmp = fcmp ogt float %a, 5.0 83 %sel = select i1 %cmp, float %div1, float %div2 84 ret float %sel 85} 86 87; But if the select is marked unpredictable, then don't turn it into a branch. 88 89define float @unpredictable_select(float %a, float %b) { 90; CHECK-LABEL: @unpredictable_select( 91; CHECK-NEXT: entry: 92; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A:%.*]], [[B:%.*]] 93; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A]], 1.000000e+00 94; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[DIV]], float 2.000000e+00, !unpredictable !0 95; CHECK-NEXT: ret float [[SEL]] 96; 97entry: 98 %div = fdiv float %a, %b 99 %cmp = fcmp ogt float %a, 1.0 100 %sel = select i1 %cmp, float %div, float 2.0, !unpredictable !0 101 ret float %sel 102} 103 104!0 = !{} 105 106; An 'fadd' is not too expensive, so it's ok to speculate. 107 108define float @fadd_no_sink(float %a, float %b) { 109; CHECK-LABEL: @fadd_no_sink( 110; CHECK-NEXT: [[ADD:%.*]] = fadd float [[A:%.*]], [[B:%.*]] 111; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float 6.000000e+00, [[A]] 112; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[ADD]], float 7.000000e+00 113; CHECK-NEXT: ret float [[SEL]] 114; 115 %add = fadd float %a, %b 116 %cmp = fcmp ogt float 6.0, %a 117 %sel = select i1 %cmp, float %add, float 7.0 118 ret float %sel 119} 120 121; Possible enhancement: sinkability is only calculated with the direct 122; operand of the select, so we don't try to sink this. The fdiv cost is not 123; taken into account. 124 125define float @fdiv_no_sink(float %a, float %b) { 126; CHECK-LABEL: @fdiv_no_sink( 127; CHECK-NEXT: entry: 128; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A:%.*]], [[B:%.*]] 129; CHECK-NEXT: [[ADD:%.*]] = fadd float [[DIV]], [[B]] 130; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A]], 1.000000e+00 131; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[ADD]], float 8.000000e+00 132; CHECK-NEXT: ret float [[SEL]] 133; 134entry: 135 %div = fdiv float %a, %b 136 %add = fadd float %div, %b 137 %cmp = fcmp ogt float %a, 1.0 138 %sel = select i1 %cmp, float %add, float 8.0 139 ret float %sel 140} 141 142; Do not transform the CFG if the select operands may have side effects. 143 144declare i64* @bar(i32, i32, i32) 145declare i64* @baz(i32, i32, i32) 146 147define i64* @calls_no_sink(i32 %in) { 148; CHECK-LABEL: @calls_no_sink( 149; CHECK-NEXT: [[CALL1:%.*]] = call i64* @bar(i32 1, i32 2, i32 3) 150; CHECK-NEXT: [[CALL2:%.*]] = call i64* @baz(i32 1, i32 2, i32 3) 151; CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i32 [[IN:%.*]], 0 152; CHECK-NEXT: [[SEL:%.*]] = select i1 [[TOBOOL]], i64* [[CALL1]], i64* [[CALL2]] 153; CHECK-NEXT: ret i64* [[SEL]] 154; 155 %call1 = call i64* @bar(i32 1, i32 2, i32 3) 156 %call2 = call i64* @baz(i32 1, i32 2, i32 3) 157 %tobool = icmp ne i32 %in, 0 158 %sel = select i1 %tobool, i64* %call1, i64* %call2 159 ret i64* %sel 160} 161 162define i32 @sdiv_no_sink(i32 %a, i32 %b) { 163; CHECK-LABEL: @sdiv_no_sink( 164; CHECK-NEXT: [[DIV1:%.*]] = sdiv i32 [[A:%.*]], [[B:%.*]] 165; CHECK-NEXT: [[DIV2:%.*]] = sdiv i32 [[B]], [[A]] 166; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[A]], 5 167; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 [[DIV1]], i32 [[DIV2]] 168; CHECK-NEXT: ret i32 [[SEL]] 169; 170 %div1 = sdiv i32 %a, %b 171 %div2 = sdiv i32 %b, %a 172 %cmp = icmp sgt i32 %a, 5 173 %sel = select i1 %cmp, i32 %div1, i32 %div2 174 ret i32 %sel 175} 176 177