imprecise-through-phis.ll
8.13 KB
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
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -loop-vectorize -mtriple=x86_64-apple-darwin %s | FileCheck %s --check-prefixes=CHECK,SSE
; RUN: opt -S -loop-vectorize -mtriple=x86_64-apple-darwin -mattr=+avx %s | FileCheck %s --check-prefixes=CHECK,AVX
; Two mostly identical functions. The only difference is the presence of
; fast-math flags on the second. The loop is a pretty simple reduction:
; for (int i = 0; i < 32; ++i)
; if (arr[i] != 42)
; tot += arr[i];
define double @sumIfScalar(double* nocapture readonly %arr) {
; CHECK-LABEL: @sumIfScalar(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[NEXT_ITER:%.*]] ]
; CHECK-NEXT: [[TOT:%.*]] = phi double [ 0.000000e+00, [[ENTRY]] ], [ [[TOT_NEXT:%.*]], [[NEXT_ITER]] ]
; CHECK-NEXT: [[ADDR:%.*]] = getelementptr double, double* [[ARR:%.*]], i32 [[I]]
; CHECK-NEXT: [[NEXTVAL:%.*]] = load double, double* [[ADDR]]
; CHECK-NEXT: [[TST:%.*]] = fcmp une double [[NEXTVAL]], 4.200000e+01
; CHECK-NEXT: br i1 [[TST]], label [[DO_ADD:%.*]], label [[NO_ADD:%.*]]
; CHECK: do.add:
; CHECK-NEXT: [[TOT_NEW:%.*]] = fadd double [[TOT]], [[NEXTVAL]]
; CHECK-NEXT: br label [[NEXT_ITER]]
; CHECK: no.add:
; CHECK-NEXT: br label [[NEXT_ITER]]
; CHECK: next.iter:
; CHECK-NEXT: [[TOT_NEXT]] = phi double [ [[TOT]], [[NO_ADD]] ], [ [[TOT_NEW]], [[DO_ADD]] ]
; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT: [[AGAIN:%.*]] = icmp ult i32 [[I_NEXT]], 32
; CHECK-NEXT: br i1 [[AGAIN]], label [[LOOP]], label [[DONE:%.*]]
; CHECK: done:
; CHECK-NEXT: [[TOT_NEXT_LCSSA:%.*]] = phi double [ [[TOT_NEXT]], [[NEXT_ITER]] ]
; CHECK-NEXT: ret double [[TOT_NEXT_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %next.iter]
%tot = phi double [0.0, %entry], [%tot.next, %next.iter]
%addr = getelementptr double, double* %arr, i32 %i
%nextval = load double, double* %addr
%tst = fcmp une double %nextval, 42.0
br i1 %tst, label %do.add, label %no.add
do.add:
%tot.new = fadd double %tot, %nextval
br label %next.iter
no.add:
br label %next.iter
next.iter:
%tot.next = phi double [%tot, %no.add], [%tot.new, %do.add]
%i.next = add i32 %i, 1
%again = icmp ult i32 %i.next, 32
br i1 %again, label %loop, label %done
done:
ret double %tot.next
}
define double @sumIfVector(double* nocapture readonly %arr) {
; SSE-LABEL: @sumIfVector(
; SSE-NEXT: entry:
; SSE-NEXT: br label [[LOOP:%.*]]
; SSE: loop:
; SSE-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[NEXT_ITER:%.*]] ]
; SSE-NEXT: [[TOT:%.*]] = phi double [ 0.000000e+00, [[ENTRY]] ], [ [[TOT_NEXT:%.*]], [[NEXT_ITER]] ]
; SSE-NEXT: [[ADDR:%.*]] = getelementptr double, double* [[ARR:%.*]], i32 [[I]]
; SSE-NEXT: [[NEXTVAL:%.*]] = load double, double* [[ADDR]]
; SSE-NEXT: [[TST:%.*]] = fcmp fast une double [[NEXTVAL]], 4.200000e+01
; SSE-NEXT: br i1 [[TST]], label [[DO_ADD:%.*]], label [[NO_ADD:%.*]]
; SSE: do.add:
; SSE-NEXT: [[TOT_NEW:%.*]] = fadd fast double [[TOT]], [[NEXTVAL]]
; SSE-NEXT: br label [[NEXT_ITER]]
; SSE: no.add:
; SSE-NEXT: br label [[NEXT_ITER]]
; SSE: next.iter:
; SSE-NEXT: [[TOT_NEXT]] = phi double [ [[TOT]], [[NO_ADD]] ], [ [[TOT_NEW]], [[DO_ADD]] ]
; SSE-NEXT: [[I_NEXT]] = add i32 [[I]], 1
; SSE-NEXT: [[AGAIN:%.*]] = icmp ult i32 [[I_NEXT]], 32
; SSE-NEXT: br i1 [[AGAIN]], label [[LOOP]], label [[DONE:%.*]]
; SSE: done:
; SSE-NEXT: [[TOT_NEXT_LCSSA:%.*]] = phi double [ [[TOT_NEXT]], [[NEXT_ITER]] ]
; SSE-NEXT: ret double [[TOT_NEXT_LCSSA]]
;
; AVX-LABEL: @sumIfVector(
; AVX-NEXT: entry:
; AVX-NEXT: br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
; AVX: vector.ph:
; AVX-NEXT: br label [[VECTOR_BODY:%.*]]
; AVX: vector.body:
; AVX-NEXT: [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
; AVX-NEXT: [[VEC_PHI:%.*]] = phi <4 x double> [ zeroinitializer, [[VECTOR_PH]] ], [ [[PREDPHI:%.*]], [[VECTOR_BODY]] ]
; AVX-NEXT: [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i32> undef, i32 [[INDEX]], i32 0
; AVX-NEXT: [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i32> [[BROADCAST_SPLATINSERT]], <4 x i32> undef, <4 x i32> zeroinitializer
; AVX-NEXT: [[INDUCTION:%.*]] = add <4 x i32> [[BROADCAST_SPLAT]], <i32 0, i32 1, i32 2, i32 3>
; AVX-NEXT: [[TMP0:%.*]] = add i32 [[INDEX]], 0
; AVX-NEXT: [[TMP1:%.*]] = getelementptr double, double* [[ARR:%.*]], i32 [[TMP0]]
; AVX-NEXT: [[TMP2:%.*]] = getelementptr double, double* [[TMP1]], i32 0
; AVX-NEXT: [[TMP3:%.*]] = bitcast double* [[TMP2]] to <4 x double>*
; AVX-NEXT: [[WIDE_LOAD:%.*]] = load <4 x double>, <4 x double>* [[TMP3]], align 8
; AVX-NEXT: [[TMP4:%.*]] = fcmp fast une <4 x double> [[WIDE_LOAD]], <double 4.200000e+01, double 4.200000e+01, double 4.200000e+01, double 4.200000e+01>
; AVX-NEXT: [[TMP5:%.*]] = fadd fast <4 x double> [[VEC_PHI]], [[WIDE_LOAD]]
; AVX-NEXT: [[TMP6:%.*]] = xor <4 x i1> [[TMP4]], <i1 true, i1 true, i1 true, i1 true>
; AVX-NEXT: [[PREDPHI]] = select <4 x i1> [[TMP4]], <4 x double> [[TMP5]], <4 x double> [[VEC_PHI]]
; AVX-NEXT: [[INDEX_NEXT]] = add i32 [[INDEX]], 4
; AVX-NEXT: [[TMP7:%.*]] = icmp eq i32 [[INDEX_NEXT]], 32
; AVX-NEXT: br i1 [[TMP7]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop !0
; AVX: middle.block:
; AVX-NEXT: [[RDX_SHUF:%.*]] = shufflevector <4 x double> [[PREDPHI]], <4 x double> undef, <4 x i32> <i32 2, i32 3, i32 undef, i32 undef>
; AVX-NEXT: [[BIN_RDX:%.*]] = fadd fast <4 x double> [[PREDPHI]], [[RDX_SHUF]]
; AVX-NEXT: [[RDX_SHUF1:%.*]] = shufflevector <4 x double> [[BIN_RDX]], <4 x double> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef>
; AVX-NEXT: [[BIN_RDX2:%.*]] = fadd fast <4 x double> [[BIN_RDX]], [[RDX_SHUF1]]
; AVX-NEXT: [[TMP8:%.*]] = extractelement <4 x double> [[BIN_RDX2]], i32 0
; AVX-NEXT: [[CMP_N:%.*]] = icmp eq i32 32, 32
; AVX-NEXT: br i1 [[CMP_N]], label [[DONE:%.*]], label [[SCALAR_PH]]
; AVX: scalar.ph:
; AVX-NEXT: [[BC_RESUME_VAL:%.*]] = phi i32 [ 32, [[MIDDLE_BLOCK]] ], [ 0, [[ENTRY:%.*]] ]
; AVX-NEXT: [[BC_MERGE_RDX:%.*]] = phi double [ 0.000000e+00, [[ENTRY]] ], [ [[TMP8]], [[MIDDLE_BLOCK]] ]
; AVX-NEXT: br label [[LOOP:%.*]]
; AVX: loop:
; AVX-NEXT: [[I:%.*]] = phi i32 [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ], [ [[I_NEXT:%.*]], [[NEXT_ITER:%.*]] ]
; AVX-NEXT: [[TOT:%.*]] = phi double [ [[BC_MERGE_RDX]], [[SCALAR_PH]] ], [ [[TOT_NEXT:%.*]], [[NEXT_ITER]] ]
; AVX-NEXT: [[ADDR:%.*]] = getelementptr double, double* [[ARR]], i32 [[I]]
; AVX-NEXT: [[NEXTVAL:%.*]] = load double, double* [[ADDR]]
; AVX-NEXT: [[TST:%.*]] = fcmp fast une double [[NEXTVAL]], 4.200000e+01
; AVX-NEXT: br i1 [[TST]], label [[DO_ADD:%.*]], label [[NO_ADD:%.*]]
; AVX: do.add:
; AVX-NEXT: [[TOT_NEW:%.*]] = fadd fast double [[TOT]], [[NEXTVAL]]
; AVX-NEXT: br label [[NEXT_ITER]]
; AVX: no.add:
; AVX-NEXT: br label [[NEXT_ITER]]
; AVX: next.iter:
; AVX-NEXT: [[TOT_NEXT]] = phi double [ [[TOT]], [[NO_ADD]] ], [ [[TOT_NEW]], [[DO_ADD]] ]
; AVX-NEXT: [[I_NEXT]] = add i32 [[I]], 1
; AVX-NEXT: [[AGAIN:%.*]] = icmp ult i32 [[I_NEXT]], 32
; AVX-NEXT: br i1 [[AGAIN]], label [[LOOP]], label [[DONE]], !llvm.loop !2
; AVX: done:
; AVX-NEXT: [[TOT_NEXT_LCSSA:%.*]] = phi double [ [[TOT_NEXT]], [[NEXT_ITER]] ], [ [[TMP8]], [[MIDDLE_BLOCK]] ]
; AVX-NEXT: ret double [[TOT_NEXT_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %next.iter]
%tot = phi double [0.0, %entry], [%tot.next, %next.iter]
%addr = getelementptr double, double* %arr, i32 %i
%nextval = load double, double* %addr
%tst = fcmp fast une double %nextval, 42.0
br i1 %tst, label %do.add, label %no.add
do.add:
%tot.new = fadd fast double %tot, %nextval
br label %next.iter
no.add:
br label %next.iter
next.iter:
%tot.next = phi double [%tot, %no.add], [%tot.new, %do.add]
%i.next = add i32 %i, 1
%again = icmp ult i32 %i.next, 32
br i1 %again, label %loop, label %done
done:
ret double %tot.next
}