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@kaityo256
Created November 21, 2021 09:57
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Logical operation of predicate registers on SVE
#include <arm_sve.h>
#include <iostream>
#include <vector>
#include <random>
void show_pr(svbool_t tp) {
int n = svcntb();
std::vector<int8_t> a(n);
std::vector<int8_t> b(n);
std::fill(a.begin(), a.end(), 1);
std::fill(b.begin(), b.end(), 0);
svint8_t va = svld1_s8(tp, a.data());
svst1_s8(tp, b.data(), va);
for (int i = 0; i < n; i++) {
std::cout << (int)b[n - i - 1];
}
std::cout << std::endl;
}
int main() {
std::vector<int8_t> a1(64), a2(64);
std::mt19937 mt(1);
std::uniform_int_distribution<> ud(0,1);
for(int i=0;i<64;i++){
a1[i] = ud(mt);
a2[i] = ud(mt);
}
svbool_t tp = svptrue_b8();
svint8_t v1= svld1_s8(tp, a1.data());
svint8_t v2= svld1_s8(tp, a2.data());
svint8_t vzero= svdup_n_s8_x(tp, 1);
svbool_t p1 = svcmpeq(tp, v1, vzero);
svbool_t p2 = svcmpeq(tp, v2, vzero);
printf("p1 = ");
show_pr(p1);
printf("p2 = ");
show_pr(p2);
printf("p1 and p2 = ");
show_pr(svand_b_z(tp, p1, p2));
printf("\n");
printf("p1 = ");
show_pr(p1);
printf("p2 = ");
show_pr(p2);
printf("p1 or p2 = ");
show_pr(svorr_b_z(tp, p1, p2));
}
@kaityo256
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$ ./a.out
p1        = 0100110100001000010010111011011100100011101100101010101000000010
p2        = 1011001111011010100000011001000011100111101111001100101110001011
p1 and p2 = 0000000100001000000000011001000000100011101100001000101000000010

p1        = 0100110100001000010010111011011100100011101100101010101000000010
p2        = 1011001111011010100000011001000011100111101111001100101110001011
p1 or p2  = 1111111111011010110010111011011111100111101111101110101110001011

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