Home | History | Annotate | Download | only in EarlyCSE 
      1 ; RUN: opt -early-cse -S < %s | FileCheck %s
      2 ; RUN: opt -basicaa -early-cse-memssa -S < %s | FileCheck %s
      3 ; Same as GVN/edge.ll, but updated to reflect EarlyCSE's less powerful
      4 ; implementation.  EarlyCSE currently doesn't exploit equality comparisons
      5 ; against constants.
      6 
      7 define i32 @f1(i32 %x) {
      8   ; CHECK-LABEL: define i32 @f1(
      9 bb0:
     10   %cmp = icmp eq i32 %x, 0
     11   br i1 %cmp, label %bb2, label %bb1
     12 bb1:
     13   br label %bb2
     14 bb2:
     15   %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     16   %foo = add i32 %cond, %x
     17   ret i32 %foo
     18   ; CHECK: bb2:
     19   ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     20 }
     21 
     22 define i32 @f2(i32 %x) {
     23   ; CHECK-LABEL: define i32 @f2(
     24 bb0:
     25   %cmp = icmp ne i32 %x, 0
     26   br i1 %cmp, label %bb1, label %bb2
     27 bb1:
     28   br label %bb2
     29 bb2:
     30   %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     31   %foo = add i32 %cond, %x
     32   ret i32 %foo
     33   ; CHECK: bb2:
     34   ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     35 }
     36 
     37 define i32 @f3(i32 %x) {
     38   ; CHECK-LABEL: define i32 @f3(
     39 bb0:
     40   switch i32 %x, label %bb1 [ i32 0, label %bb2]
     41 bb1:
     42   br label %bb2
     43 bb2:
     44   %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     45   %foo = add i32 %cond, %x
     46   ret i32 %foo
     47   ; CHECK: bb2:
     48   ; CHECK: %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
     49 }
     50 
     51 declare void @g(i1)
     52 define void @f4(i8 * %x)  {
     53 ; CHECK-LABEL: define void @f4(
     54 bb0:
     55   %y = icmp eq i8* null, %x
     56   br i1 %y, label %bb2, label %bb1
     57 bb1:
     58   br label %bb2
     59 bb2:
     60   %zed = icmp eq i8* null, %x
     61   call void @g(i1 %zed)
     62 ; CHECK: call void @g(i1 %y)
     63   ret void
     64 }
     65 
     66 define double @fcmp_oeq_not_zero(double %x, double %y) {
     67 entry:
     68   %cmp = fcmp oeq double %y, 2.0
     69   br i1 %cmp, label %if, label %return
     70 
     71 if:
     72   %div = fdiv double %x, %y
     73   br label %return
     74 
     75 return:
     76   %retval = phi double [ %div, %if ], [ %x, %entry ]
     77   ret double %retval
     78 
     79 ; CHECK-LABEL: define double @fcmp_oeq_not_zero(
     80 ; CHECK: %div = fdiv double %x, %y
     81 }
     82 
     83 define double @fcmp_une_not_zero(double %x, double %y) {
     84 entry:
     85   %cmp = fcmp une double %y, 2.0
     86   br i1 %cmp, label %return, label %else
     87 
     88 else:
     89   %div = fdiv double %x, %y
     90   br label %return
     91 
     92 return:
     93   %retval = phi double [ %div, %else ], [ %x, %entry ]
     94   ret double %retval
     95 
     96 ; CHECK-LABEL: define double @fcmp_une_not_zero(
     97 ; CHECK: %div = fdiv double %x, %y
     98 }
     99 
    100 ; PR22376 - We can't propagate zero constants because -0.0 
    101 ; compares equal to 0.0. If %y is -0.0 in this test case,
    102 ; we would produce the wrong sign on the infinity return value.
    103 define double @fcmp_oeq_zero(double %x, double %y) {
    104 entry:
    105   %cmp = fcmp oeq double %y, 0.0
    106   br i1 %cmp, label %if, label %return
    107 
    108 if:
    109   %div = fdiv double %x, %y
    110   br label %return
    111 
    112 return:
    113   %retval = phi double [ %div, %if ], [ %x, %entry ]
    114   ret double %retval
    115 
    116 ; CHECK-LABEL: define double @fcmp_oeq_zero(
    117 ; CHECK: %div = fdiv double %x, %y
    118 }
    119 
    120 define double @fcmp_une_zero(double %x, double %y) {
    121 entry:
    122   %cmp = fcmp une double %y, -0.0
    123   br i1 %cmp, label %return, label %else
    124 
    125 else:
    126   %div = fdiv double %x, %y
    127   br label %return
    128 
    129 return:
    130   %retval = phi double [ %div, %else ], [ %x, %entry ]
    131   ret double %retval
    132 
    133 ; CHECK-LABEL: define double @fcmp_une_zero(
    134 ; CHECK: %div = fdiv double %x, %y
    135 }
    136 
    137 ; We also cannot propagate a value if it's not a constant.
    138 ; This is because the value could be 0.0 or -0.0.
    139 
    140 define double @fcmp_oeq_maybe_zero(double %x, double %y, double %z1, double %z2) {
    141 entry:
    142  %z = fadd double %z1, %z2
    143  %cmp = fcmp oeq double %y, %z
    144  br i1 %cmp, label %if, label %return
    145 
    146 if:
    147  %div = fdiv double %x, %z
    148  br label %return
    149 
    150 return:
    151  %retval = phi double [ %div, %if ], [ %x, %entry ]
    152  ret double %retval
    153 
    154 ; CHECK-LABEL: define double @fcmp_oeq_maybe_zero(
    155 ; CHECK: %div = fdiv double %x, %z
    156 }
    157 
    158 define double @fcmp_une_maybe_zero(double %x, double %y, double %z1, double %z2) {
    159 entry:
    160  %z = fadd double %z1, %z2
    161  %cmp = fcmp une double %y, %z
    162  br i1 %cmp, label %return, label %else
    163 
    164 else:
    165  %div = fdiv double %x, %z
    166  br label %return
    167 
    168 return:
    169  %retval = phi double [ %div, %else ], [ %x, %entry ]
    170  ret double %retval
    171 
    172 ; CHECK-LABEL: define double @fcmp_une_maybe_zero(
    173 ; CHECK: %div = fdiv double %x, %z
    174 }
    175