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            Last change
 on this file since f3811df was             44856ed, checked in by Michael Brooks <mlbrooks@…>, 4 years ago           | 
        
        
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Baseline "new" vector, with iterators. 
 
Implementation has not had thorough correctness testing, e.g. checking wraparound 
behaviours, and at least one such case is commented as unimplemented. 
 
Implementation has not been optimized at the instruction path level, though a basic 
iteration performance check has it within 5% of c++ std::vector. 
 
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            File size:
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| 1 | #include "vector2.hfa"
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| 2 | 
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| 3 | #include <time.h>
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| 4 | 
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| 5 | enum { NumElements = 10000, NumReps = 50000 };
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| 6 | 
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| 7 | // A layer of indirection to improve performance (naturally!)
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| 8 | // Works around trac #248.
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| 9 | // This test keeps a vector of notfloat, instead of a vector of float.  The optimizer removes this added indirection.
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| 10 | // Furthermore, by passing notfloat's static-inline constructors, defined in this compile unit, to vector, the vector's element's constructors become eligible for inlining.
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| 11 | // Skipping this optimization costs about a 25% slowdown.
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| 12 | struct notfloat{ inline float; };
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| 13 | 
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| 14 | int main() {
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| 15 |     clock_t start, end;
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| 16 |     vector(notfloat) x = { 4 };
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| 17 |     for (i; NumElements) {
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| 18 |         push_last(x, (notfloat){0.1f * i});
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| 19 |     }
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| 20 |     float total;
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| 21 |     start = clock();
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| 22 |     for (rep; NumReps) {
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| 23 |         total = 0;
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| 24 |         while( vector_exit(notfloat) it = x`origin; it`moveNext ) {
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| 25 |             total += it`val;
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| 26 |         }
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| 27 |     }
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| 28 |     end = clock();
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| 29 |     printf("last total was %f\n", total);
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| 30 |     double elapsed = ((double) (end - start)) / CLOCKS_PER_SEC; \
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| 31 |     printf("iterating duration was %f\n", elapsed);
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| 32 | }
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