reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140
  141
  142
  143
  144
  145
  146
  147
  148
  149
  150
  151
  152
  153
  154
  155
  156
  157
  158
  159
  160
  161
  162
  163
  164
  165
  166
  167
  168
  169
  170
  171
  172
  173
  174
  175
  176
  177
  178
  179
  180
  181
  182
  183
  184
  185
  186
  187
  188
; RUN: opt -S -licm < %s | FileCheck %s
; RUN: opt -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' -S %s | FileCheck %s

; UDiv is safe to speculate if the denominator is known non-zero.

; CHECK-LABEL: @safe_udiv(
; CHECK:      %div = udiv i64 %x, 2
; CHECK-NEXT: br label %for.body

define void @safe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
entry:
  br label %for.body

for.body:                                         ; preds = %entry, %for.inc
  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
  %0 = load i32, i32* %arrayidx, align 4
  %tobool = icmp eq i32 %0, 0
  br i1 %tobool, label %for.inc, label %if.then

if.then:                                          ; preds = %for.body
  %div = udiv i64 %x, 2
  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
  store i64 %div, i64* %arrayidx1, align 8
  br label %for.inc

for.inc:                                          ; preds = %if.then, %for.body
  %inc = add i64 %i.02, 1
  %cmp = icmp slt i64 %inc, %n
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.inc, %entry
  ret void
}

; UDiv is unsafe to speculate if the denominator is not known non-zero.

; CHECK-LABEL: @unsafe_udiv(
; CHECK-NOT:  udiv
; CHECK: for.body:

define void @unsafe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
entry:
  br label %for.body

for.body:                                         ; preds = %entry, %for.inc
  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
  %0 = load i32, i32* %arrayidx, align 4
  %tobool = icmp eq i32 %0, 0
  br i1 %tobool, label %for.inc, label %if.then

if.then:                                          ; preds = %for.body
  %div = udiv i64 %x, %m
  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
  store i64 %div, i64* %arrayidx1, align 8
  br label %for.inc

for.inc:                                          ; preds = %if.then, %for.body
  %inc = add i64 %i.02, 1
  %cmp = icmp slt i64 %inc, %n
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.inc, %entry
  ret void
}

; SDiv is safe to speculate if the denominator is known non-zero and
; known to have at least one zero bit.

; CHECK-LABEL: @safe_sdiv(
; CHECK:      %div = sdiv i64 %x, 2
; CHECK-NEXT: br label %for.body

define void @safe_sdiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
entry:
  %and = and i64 %m, -3
  br label %for.body

for.body:                                         ; preds = %entry, %for.inc
  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
  %0 = load i32, i32* %arrayidx, align 4
  %tobool = icmp eq i32 %0, 0
  br i1 %tobool, label %for.inc, label %if.then

if.then:                                          ; preds = %for.body
  %div = sdiv i64 %x, 2
  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
  store i64 %div, i64* %arrayidx1, align 8
  br label %for.inc

for.inc:                                          ; preds = %if.then, %for.body
  %inc = add i64 %i.02, 1
  %cmp = icmp slt i64 %inc, %n
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.inc, %entry
  ret void
}

; SDiv is unsafe to speculate if the denominator is not known non-zero.

; CHECK-LABEL: @unsafe_sdiv_a(
; CHECK-NOT:  sdiv
; CHECK: for.body:

define void @unsafe_sdiv_a(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
entry:
  %or = or i64 %m, 1
  br label %for.body

for.body:                                         ; preds = %entry, %for.inc
  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
  %0 = load i32, i32* %arrayidx, align 4
  %tobool = icmp eq i32 %0, 0
  br i1 %tobool, label %for.inc, label %if.then

if.then:                                          ; preds = %for.body
  %div = sdiv i64 %x, %or
  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
  store i64 %div, i64* %arrayidx1, align 8
  br label %for.inc

for.inc:                                          ; preds = %if.then, %for.body
  %inc = add i64 %i.02, 1
  %cmp = icmp slt i64 %inc, %n
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.inc, %entry
  ret void
}

; SDiv is unsafe to speculate if the denominator is not known to have a zero bit.

; CHECK-LABEL: @unsafe_sdiv_b(
; CHECK-NOT:  sdiv
; CHECK: for.body:

define void @unsafe_sdiv_b(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
entry:
  %and = and i64 %m, -3
  br label %for.body

for.body:                                         ; preds = %entry, %for.inc
  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
  %0 = load i32, i32* %arrayidx, align 4
  %tobool = icmp eq i32 %0, 0
  br i1 %tobool, label %for.inc, label %if.then

if.then:                                          ; preds = %for.body
  %div = sdiv i64 %x, %and
  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
  store i64 %div, i64* %arrayidx1, align 8
  br label %for.inc

for.inc:                                          ; preds = %if.then, %for.body
  %inc = add i64 %i.02, 1
  %cmp = icmp slt i64 %inc, %n
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.inc, %entry
  ret void
}

; SDiv is unsafe to speculate inside an infinite loop.

define void @unsafe_sdiv_c(i64 %a, i64 %b, i64* %p) {
entry:
; CHECK: entry:
; CHECK-NOT: sdiv
; CHECK: br label %for.body
  br label %for.body

for.body:
  %c = icmp eq i64 %b, 0
  br i1 %c, label %backedge, label %if.then

if.then:
  %d = sdiv i64 %a, %b
  store i64 %d, i64* %p
  br label %backedge

backedge:
  br label %for.body
}