1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt -codegenprepare -S < %s | FileCheck %s 3; RUN: opt -debugify -codegenprepare -S < %s | FileCheck %s -check-prefix=DEBUG 4 5target triple = "x86_64-unknown-unknown" 6 7; Nothing to sink and convert here. 8 9define i32 @no_sink(double %a, double* %b, i32 %x, i32 %y) { 10; CHECK-LABEL: @no_sink( 11; CHECK-NEXT: entry: 12; CHECK-NEXT: [[LOAD:%.*]] = load double, double* [[B:%.*]], align 8 13; CHECK-NEXT: [[CMP:%.*]] = fcmp olt double [[LOAD]], [[A:%.*]] 14; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 [[X:%.*]], i32 [[Y:%.*]] 15; CHECK-NEXT: ret i32 [[SEL]] 16; 17entry: 18 %load = load double, double* %b, align 8 19 %cmp = fcmp olt double %load, %a 20 %sel = select i1 %cmp, i32 %x, i32 %y 21 ret i32 %sel 22} 23 24 25; An 'fdiv' is expensive, so sink it rather than speculatively execute it. 26 27define float @fdiv_true_sink(float %a, float %b) { 28; CHECK-LABEL: @fdiv_true_sink( 29; CHECK-NEXT: entry: 30; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 1.000000e+00 31; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_TRUE_SINK:%.*]], label [[SELECT_END:%.*]] 32; CHECK: select.true.sink: 33; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 34; CHECK-NEXT: br label [[SELECT_END]] 35; CHECK: select.end: 36; CHECK-NEXT: [[SEL:%.*]] = phi float [ [[DIV]], [[SELECT_TRUE_SINK]] ], [ 2.000000e+00, [[ENTRY:%.*]] ] 37; CHECK-NEXT: ret float [[SEL]] 38; 39; DEBUG-LABEL: @fdiv_true_sink( 40; DEBUG-NEXT: entry: 41; DEBUG-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 1.000000e+00 42; DEBUG-NEXT: call void @llvm.dbg.value(metadata i1 [[CMP]] 43; DEBUG-NEXT: br i1 [[CMP]], label [[SELECT_TRUE_SINK:%.*]], label [[SELECT_END:%.*]], !dbg 44; DEBUG: select.true.sink: 45; DEBUG-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 46; DEBUG-NEXT: call void @llvm.dbg.value(metadata float [[DIV]] 47; DEBUG-NEXT: br label [[SELECT_END]], !dbg 48; DEBUG: select.end: 49; DEBUG-NEXT: [[SEL:%.*]] = phi float [ [[DIV]], [[SELECT_TRUE_SINK]] ], [ 2.000000e+00, [[ENTRY:%.*]] ], !dbg 50; DEBUG-NEXT: call void @llvm.dbg.value(metadata float [[SEL]] 51; DEBUG-NEXT: ret float [[SEL]] 52; 53entry: 54 %div = fdiv float %a, %b 55 %cmp = fcmp ogt float %a, 1.0 56 %sel = select i1 %cmp, float %div, float 2.0 57 ret float %sel 58} 59 60define float @fdiv_false_sink(float %a, float %b) { 61; CHECK-LABEL: @fdiv_false_sink( 62; CHECK-NEXT: entry: 63; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 3.000000e+00 64; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_END:%.*]], label [[SELECT_FALSE_SINK:%.*]] 65; CHECK: select.false.sink: 66; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 67; CHECK-NEXT: br label [[SELECT_END]] 68; CHECK: select.end: 69; CHECK-NEXT: [[SEL:%.*]] = phi float [ 4.000000e+00, [[ENTRY:%.*]] ], [ [[DIV]], [[SELECT_FALSE_SINK]] ] 70; CHECK-NEXT: ret float [[SEL]] 71; 72; DEBUG-LABEL: @fdiv_false_sink( 73; DEBUG-NEXT: entry: 74; DEBUG-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 3.000000e+00 75; DEBUG-NEXT: call void @llvm.dbg.value(metadata i1 [[CMP]] 76; DEBUG-NEXT: br i1 [[CMP]], label [[SELECT_END:%.*]], label [[SELECT_FALSE_SINK:%.*]], !dbg 77; DEBUG: select.false.sink: 78; DEBUG-NEXT: [[DIV:%.*]] = fdiv float [[A]], [[B:%.*]] 79; DEBUG-NEXT: call void @llvm.dbg.value(metadata float [[DIV]] 80; DEBUG-NEXT: br label [[SELECT_END]], !dbg 81; DEBUG: select.end: 82; DEBUG-NEXT: [[SEL:%.*]] = phi float [ 4.000000e+00, [[ENTRY:%.*]] ], [ [[DIV]], [[SELECT_FALSE_SINK]] ], !dbg 83; DEBUG-NEXT: call void @llvm.dbg.value(metadata float [[SEL]] 84; DEBUG-NEXT: ret float [[SEL]], !dbg 85; 86entry: 87 %div = fdiv float %a, %b 88 %cmp = fcmp ogt float %a, 3.0 89 %sel = select i1 %cmp, float 4.0, float %div 90 ret float %sel 91} 92 93define float @fdiv_both_sink(float %a, float %b) { 94; CHECK-LABEL: @fdiv_both_sink( 95; CHECK-NEXT: entry: 96; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A:%.*]], 5.000000e+00 97; CHECK-NEXT: br i1 [[CMP]], label [[SELECT_TRUE_SINK:%.*]], label [[SELECT_FALSE_SINK:%.*]] 98; CHECK: select.true.sink: 99; CHECK-NEXT: [[DIV1:%.*]] = fdiv float [[A]], [[B:%.*]] 100; CHECK-NEXT: br label [[SELECT_END:%.*]] 101; CHECK: select.false.sink: 102; CHECK-NEXT: [[DIV2:%.*]] = fdiv float [[B]], [[A]] 103; CHECK-NEXT: br label [[SELECT_END]] 104; CHECK: select.end: 105; CHECK-NEXT: [[SEL:%.*]] = phi float [ [[DIV1]], [[SELECT_TRUE_SINK]] ], [ [[DIV2]], [[SELECT_FALSE_SINK]] ] 106; CHECK-NEXT: ret float [[SEL]] 107; 108entry: 109 %div1 = fdiv float %a, %b 110 %div2 = fdiv float %b, %a 111 %cmp = fcmp ogt float %a, 5.0 112 %sel = select i1 %cmp, float %div1, float %div2 113 ret float %sel 114} 115 116; But if the select is marked unpredictable, then don't turn it into a branch. 117 118define float @unpredictable_select(float %a, float %b) { 119; CHECK-LABEL: @unpredictable_select( 120; CHECK-NEXT: entry: 121; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A:%.*]], [[B:%.*]] 122; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A]], 1.000000e+00 123; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[DIV]], float 2.000000e+00, !unpredictable !0 124; CHECK-NEXT: ret float [[SEL]] 125; 126entry: 127 %div = fdiv float %a, %b 128 %cmp = fcmp ogt float %a, 1.0 129 %sel = select i1 %cmp, float %div, float 2.0, !unpredictable !0 130 ret float %sel 131} 132 133!0 = !{} 134 135; An 'fadd' is not too expensive, so it's ok to speculate. 136 137define float @fadd_no_sink(float %a, float %b) { 138; CHECK-LABEL: @fadd_no_sink( 139; CHECK-NEXT: [[ADD:%.*]] = fadd float [[A:%.*]], [[B:%.*]] 140; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float 6.000000e+00, [[A]] 141; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[ADD]], float 7.000000e+00 142; CHECK-NEXT: ret float [[SEL]] 143; 144 %add = fadd float %a, %b 145 %cmp = fcmp ogt float 6.0, %a 146 %sel = select i1 %cmp, float %add, float 7.0 147 ret float %sel 148} 149 150; Possible enhancement: sinkability is only calculated with the direct 151; operand of the select, so we don't try to sink this. The fdiv cost is not 152; taken into account. 153 154define float @fdiv_no_sink(float %a, float %b) { 155; CHECK-LABEL: @fdiv_no_sink( 156; CHECK-NEXT: entry: 157; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[A:%.*]], [[B:%.*]] 158; CHECK-NEXT: [[ADD:%.*]] = fadd float [[DIV]], [[B]] 159; CHECK-NEXT: [[CMP:%.*]] = fcmp ogt float [[A]], 1.000000e+00 160; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], float [[ADD]], float 8.000000e+00 161; CHECK-NEXT: ret float [[SEL]] 162; 163entry: 164 %div = fdiv float %a, %b 165 %add = fadd float %div, %b 166 %cmp = fcmp ogt float %a, 1.0 167 %sel = select i1 %cmp, float %add, float 8.0 168 ret float %sel 169} 170 171; Do not transform the CFG if the select operands may have side effects. 172 173declare i64* @bar(i32, i32, i32) 174declare i64* @baz(i32, i32, i32) 175 176define i64* @calls_no_sink(i32 %in) { 177; CHECK-LABEL: @calls_no_sink( 178; CHECK-NEXT: [[CALL1:%.*]] = call i64* @bar(i32 1, i32 2, i32 3) 179; CHECK-NEXT: [[CALL2:%.*]] = call i64* @baz(i32 1, i32 2, i32 3) 180; CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i32 [[IN:%.*]], 0 181; CHECK-NEXT: [[SEL:%.*]] = select i1 [[TOBOOL]], i64* [[CALL1]], i64* [[CALL2]] 182; CHECK-NEXT: ret i64* [[SEL]] 183; 184 %call1 = call i64* @bar(i32 1, i32 2, i32 3) 185 %call2 = call i64* @baz(i32 1, i32 2, i32 3) 186 %tobool = icmp ne i32 %in, 0 187 %sel = select i1 %tobool, i64* %call1, i64* %call2 188 ret i64* %sel 189} 190 191define i32 @sdiv_no_sink(i32 %a, i32 %b) { 192; CHECK-LABEL: @sdiv_no_sink( 193; CHECK-NEXT: [[DIV1:%.*]] = sdiv i32 [[A:%.*]], [[B:%.*]] 194; CHECK-NEXT: [[DIV2:%.*]] = sdiv i32 [[B]], [[A]] 195; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i32 [[A]], 5 196; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 [[DIV1]], i32 [[DIV2]] 197; CHECK-NEXT: ret i32 [[SEL]] 198; 199 %div1 = sdiv i32 %a, %b 200 %div2 = sdiv i32 %b, %a 201 %cmp = icmp sgt i32 %a, 5 202 %sel = select i1 %cmp, i32 %div1, i32 %div2 203 ret i32 %sel 204} 205 206