1 /*
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23
24 /**
25 * @test
26 * @bug JDK-8310130
27 * @summary Special test cases for PhaseIdealLoop::move_unordered_reduction_out_of_loop
28 * Here a case with partial vectorization of the reduction.
29 * @library /test/lib /
30 * @run driver compiler.loopopts.superword.TestUnorderedReductionPartialVectorization
31 */
32
33 package compiler.loopopts.superword;
34
35 import compiler.lib.ir_framework.*;
36
37 public class TestUnorderedReductionPartialVectorization {
38 static final int RANGE = 1024;
39 static final int ITER = 10;
40
41 public static void main(String[] args) {
42 TestFramework.runWithFlags("-XX:+UnlockExperimentalVMOptions", "-XX:-UseCompactObjectHeaders", "-XX:-AlignVector");
43 TestFramework.runWithFlags("-XX:+UnlockExperimentalVMOptions", "-XX:-UseCompactObjectHeaders", "-XX:+AlignVector");
44 TestFramework.runWithFlags("-XX:+UnlockExperimentalVMOptions", "-XX:+UseCompactObjectHeaders", "-XX:-AlignVector");
45 TestFramework.runWithFlags("-XX:+UnlockExperimentalVMOptions", "-XX:+UseCompactObjectHeaders", "-XX:+AlignVector");
46 }
47
48 @Run(test = {"test1"})
49 @Warmup(0)
50 public void runTests() throws Exception {
51 int[] data = new int[RANGE];
52
53 init(data);
54 for (int i = 0; i < ITER; i++) {
55 long r1 = test1(data, i);
56 long r2 = ref1(data, i);
57 if (r1 != r2) {
58 throw new RuntimeException("Wrong result test1: " + r1 + " != " + r2);
59 }
60 }
61 }
62
63 @Test
64 @IR(counts = {IRNode.LOAD_VECTOR_I, IRNode.VECTOR_SIZE + "min(max_int, max_long)", "> 0",
65 IRNode.VECTOR_CAST_I2L, IRNode.VECTOR_SIZE + "min(max_int, max_long)", "> 0",
66 IRNode.OR_REDUCTION_V, "> 0",},
67 applyIfOr = {"AlignVector", "false", "UseCompactObjectHeaders", "false"},
68 applyIfPlatform = {"64-bit", "true"},
69 applyIfCPUFeatureOr = {"avx2", "true"})
70 static long test1(int[] data, long sum) {
71 for (int i = 0; i < data.length; i+=2) {
72 // Mixing int and long ops means we only end up allowing half of the int
73 // loads in one pack, and we have two int packs. The first pack has one
74 // of the pairs missing because of the store, which creates a dependency.
75 // The first pack is rejected and left as scalar, the second pack succeeds
76 // with vectorization. That means we have a mixed scalar/vector reduction
77 // chain. This way it is possible that a vector-reduction has a scalar
78 // reduction as input, which is neigher a phi nor a vector reduction.
79 // In such a case, we must bail out of the optimization in
80 // PhaseIdealLoop::move_unordered_reduction_out_of_loop
81 int v = data[i]; // int read
82 data[0] = 0; // ruin the first pack
83 sum |= v; // long reduction (and implicit cast from int to long)
84
85 // This example used to rely on that reductions were ignored in SuperWord::unrolling_analysis,
86 // and hence the largest data type in the loop was the ints. This would then unroll the doubles
87 // for twice the vector length, and this resulted in us having twice as many packs. Because of
88 // the store "data[0] = 0", the first packs were destroyed, since they do not have power of 2
89 // size.
90 // Now, we no longer ignore reductions, and now we unroll half as much before SuperWord. This
91 // means we would only get one pack per operation, and that one would get ruined, and we have
92 // no vectorization. We now ensure there are again 2 packs per operation with a 2x hand unroll.
93 int v2 = data[i + 1];
94 sum |= v2;
95
96 // With AlignVector, we need 8-byte alignment of vector loads/stores.
97 // UseCompactObjectHeaders=false UseCompactObjectHeaders=true
98 // adr = base + 16 + 8*i -> always adr = base + 12 + 8*i -> never
99 // -> vectorize -> no vectorization
100 }
101 return sum;
102 }
103
104 static long ref1(int[] data, long sum) {
105 for (int i = 0; i < data.length; i++) {
106 int v = data[i];
107 data[0] = 0;
108 sum |= v;
109 }
110 return sum;
111 }
112
113 static void init(int[] data) {
114 for (int i = 0; i < RANGE; i++) {
115 data[i] = i + 1;
116 }
117 }
118 }