1; RUN: opt -early-cse -S < %s | FileCheck %s 2; Same as GVN/edge.ll, but updated to reflect EarlyCSE's less powerful 3; implementation. EarlyCSE currently doesn't exploit equality comparisons 4; against constants. 5 6define i32 @f1(i32 %x) { 7 ; CHECK-LABEL: define i32 @f1( 8bb0: 9 %cmp = icmp eq i32 %x, 0 10 br i1 %cmp, label %bb2, label %bb1 11bb1: 12 br label %bb2 13bb2: 14 %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 15 %foo = add i32 %cond, %x 16 ret i32 %foo 17 ; CHECK: bb2: 18 ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 19} 20 21define i32 @f2(i32 %x) { 22 ; CHECK-LABEL: define i32 @f2( 23bb0: 24 %cmp = icmp ne i32 %x, 0 25 br i1 %cmp, label %bb1, label %bb2 26bb1: 27 br label %bb2 28bb2: 29 %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 30 %foo = add i32 %cond, %x 31 ret i32 %foo 32 ; CHECK: bb2: 33 ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 34} 35 36define i32 @f3(i32 %x) { 37 ; CHECK-LABEL: define i32 @f3( 38bb0: 39 switch i32 %x, label %bb1 [ i32 0, label %bb2] 40bb1: 41 br label %bb2 42bb2: 43 %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 44 %foo = add i32 %cond, %x 45 ret i32 %foo 46 ; CHECK: bb2: 47 ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ] 48} 49 50declare void @g(i1) 51define void @f4(i8 * %x) { 52; CHECK-LABEL: define void @f4( 53bb0: 54 %y = icmp eq i8* null, %x 55 br i1 %y, label %bb2, label %bb1 56bb1: 57 br label %bb2 58bb2: 59 %zed = icmp eq i8* null, %x 60 call void @g(i1 %zed) 61; CHECK: call void @g(i1 %y) 62 ret void 63} 64 65define double @fcmp_oeq_not_zero(double %x, double %y) { 66entry: 67 %cmp = fcmp oeq double %y, 2.0 68 br i1 %cmp, label %if, label %return 69 70if: 71 %div = fdiv double %x, %y 72 br label %return 73 74return: 75 %retval = phi double [ %div, %if ], [ %x, %entry ] 76 ret double %retval 77 78; CHECK-LABEL: define double @fcmp_oeq_not_zero( 79; CHECK: %div = fdiv double %x, %y 80} 81 82define double @fcmp_une_not_zero(double %x, double %y) { 83entry: 84 %cmp = fcmp une double %y, 2.0 85 br i1 %cmp, label %return, label %else 86 87else: 88 %div = fdiv double %x, %y 89 br label %return 90 91return: 92 %retval = phi double [ %div, %else ], [ %x, %entry ] 93 ret double %retval 94 95; CHECK-LABEL: define double @fcmp_une_not_zero( 96; CHECK: %div = fdiv double %x, %y 97} 98 99; PR22376 - We can't propagate zero constants because -0.0 100; compares equal to 0.0. If %y is -0.0 in this test case, 101; we would produce the wrong sign on the infinity return value. 102define double @fcmp_oeq_zero(double %x, double %y) { 103entry: 104 %cmp = fcmp oeq double %y, 0.0 105 br i1 %cmp, label %if, label %return 106 107if: 108 %div = fdiv double %x, %y 109 br label %return 110 111return: 112 %retval = phi double [ %div, %if ], [ %x, %entry ] 113 ret double %retval 114 115; CHECK-LABEL: define double @fcmp_oeq_zero( 116; CHECK: %div = fdiv double %x, %y 117} 118 119define double @fcmp_une_zero(double %x, double %y) { 120entry: 121 %cmp = fcmp une double %y, -0.0 122 br i1 %cmp, label %return, label %else 123 124else: 125 %div = fdiv double %x, %y 126 br label %return 127 128return: 129 %retval = phi double [ %div, %else ], [ %x, %entry ] 130 ret double %retval 131 132; CHECK-LABEL: define double @fcmp_une_zero( 133; CHECK: %div = fdiv double %x, %y 134} 135 136; We also cannot propagate a value if it's not a constant. 137; This is because the value could be 0.0 or -0.0. 138 139define double @fcmp_oeq_maybe_zero(double %x, double %y, double %z1, double %z2) { 140entry: 141 %z = fadd double %z1, %z2 142 %cmp = fcmp oeq double %y, %z 143 br i1 %cmp, label %if, label %return 144 145if: 146 %div = fdiv double %x, %z 147 br label %return 148 149return: 150 %retval = phi double [ %div, %if ], [ %x, %entry ] 151 ret double %retval 152 153; CHECK-LABEL: define double @fcmp_oeq_maybe_zero( 154; CHECK: %div = fdiv double %x, %z 155} 156 157define double @fcmp_une_maybe_zero(double %x, double %y, double %z1, double %z2) { 158entry: 159 %z = fadd double %z1, %z2 160 %cmp = fcmp une double %y, %z 161 br i1 %cmp, label %return, label %else 162 163else: 164 %div = fdiv double %x, %z 165 br label %return 166 167return: 168 %retval = phi double [ %div, %else ], [ %x, %entry ] 169 ret double %retval 170 171; CHECK-LABEL: define double @fcmp_une_maybe_zero( 172; CHECK: %div = fdiv double %x, %z 173} 174