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1 // PR c++/53792 - [C++11] improving compiler-time constexpr evaluation
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2 // { dg-do compile { target c++11 } }
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3 // { dg-additional-options "-O1 -fdump-tree-optimized" }
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4
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5 struct entry
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6 {
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7 char const* label;
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8 int value;
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9 };
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10
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11 constexpr bool same (char const *x, char const *y)
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12 {
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13 return !*x && !*y ? true : /* default */ (*x == *y && same (x + 1, y + 1));
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14 }
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15
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16 constexpr int
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17 keyToValue (char const *label, entry const *entries)
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18 {
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19 return !entries->label ? entries->value
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20 : same (entries->label, label) ? entries->value
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21 : /* default */ keyToValue (label, entries + 1);
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22 }
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23
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24 constexpr entry foo[] = {{"Foo", 0}, {"Bar", 1}, {"FooBar", 2}, {0, -1}};
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25
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26 int bar ()
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27 {
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28 int result = keyToValue ("Foo", foo);
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29 return result;
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30 }
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31
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32 int baz ()
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33 {
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34 constexpr int result = keyToValue ("Foo", foo);
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35 return result;
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36 }
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37
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38 // Verify that the call to the keyToValue() constexpr function is inlined
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39 // regardless of whether or not it's invoked in a constexpr expression.
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40 // { dg-final { scan-tree-dump-not "keyToValue" "optimized" } }
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