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#include "Halide.h"
#include "halide_benchmark.h"
using namespace Halide;
int main(int argc, char **argv) {
Target target = get_jit_target_from_environment();
if (target.arch == Target::WebAssembly) {
printf("[SKIP] Performance tests are meaningless and/or misleading under WebAssembly interpreter.\n");
return 0;
}
double times[3] = {0.f, 0.f, 0.f};
for (int sz = 1; sz < 32; sz = sz * 2 + 1) {
for (int c = 0; c < 3; c++) {
MemoryType mem_type;
bool use_bound;
// Check three cases:
if (c == 0) {
// Allocation on the stack where size is known.
mem_type = MemoryType::Stack;
use_bound = true;
} else if (c == 1) {
// Allocation on the stack where the size is dynamic
mem_type = MemoryType::Stack;
use_bound = false;
} else {
// Allocation on the heap where the size is dynamic
mem_type = MemoryType::Heap;
use_bound = false;
}
Var x, y;
std::vector<Func> fs;
Expr e = 0.0f;
for (int j = 0; j < 10; j++) {
Func f;
f(x, y) = x * j + y;
e += f(x, y);
fs.push_back(f);
}
Func g;
g(x, y) = e;
Var yo, yi;
// Place the y loop body in its own function with its own
// stack frame by making a parallel loop of some size
// which will be 1 in practice.
Param<int> task_size;
g.split(y, yo, yi, task_size).parallel(yi);
for (auto f : fs) {
f.compute_at(g, yi).store_in(mem_type);
if (use_bound) {
f.bound_extent(x, sz);
}
}
Buffer<float> out(sz, 1024);
task_size.set(1);
double t = 1e3 * Tools::benchmark(10, 1 + 100 / sz, [&]() {
g.realize(out);
});
times[c] += t;
}
}
printf("Constant-sized stack allocation: %f\n"
"Use alloca: %f\n"
"Use malloc: %f\n",
times[0], times[1], times[2]);
if (times[0] > times[2] || times[1] > times[2]) {
printf("Stack allocations should be cheaper than heap allocations\n");
return 1;
}
printf("Success!\n");
return 0;
}
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