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/*
* Test R5900-specific three-operand MADD and MADD1.
*/
#include <stdio.h>
#include <inttypes.h>
#include <assert.h>
int64_t madd(int64_t a, int32_t rs, int32_t rt)
{
int32_t lo = a;
int32_t hi = a >> 32;
int32_t rd;
int64_t r;
__asm__ __volatile__ (
" mtlo %5\n"
" mthi %6\n"
" madd %0, %3, %4\n"
" mflo %1\n"
" mfhi %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt), "r" (lo), "r" (hi));
r = ((int64_t)hi << 32) | (uint32_t)lo;
assert(a + (int64_t)rs * rt == r);
assert(rd == lo);
return r;
}
int64_t madd1(int64_t a, int32_t rs, int32_t rt)
{
int32_t lo = a;
int32_t hi = a >> 32;
int32_t rd;
int64_t r;
__asm__ __volatile__ (
" mtlo1 %5\n"
" mthi1 %6\n"
" madd1 %0, %3, %4\n"
" mflo1 %1\n"
" mfhi1 %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt), "r" (lo), "r" (hi));
r = ((int64_t)hi << 32) | (uint32_t)lo;
assert(a + (int64_t)rs * rt == r);
assert(rd == lo);
return r;
}
static int64_t madd_variants(int64_t a, int32_t rs, int32_t rt)
{
int64_t rd = madd(a, rs, rt);
int64_t rd1 = madd1(a, rs, rt);
assert(rd == rd1);
return rd;
}
static void verify_madd(int64_t a, int32_t rs, int32_t rt, int64_t expected)
{
assert(madd_variants(a, rs, rt) == expected);
assert(madd_variants(a, -rs, rt) == a + a - expected);
assert(madd_variants(a, rs, -rt) == a + a - expected);
assert(madd_variants(a, -rs, -rt) == expected);
}
int main()
{
verify_madd(13, 17, 19, 336);
return 0;
}
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