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/*
* Test R5900-specific three-operand MULTU and MULTU1.
*/
#include <stdio.h>
#include <inttypes.h>
#include <assert.h>
static uint64_t multu(uint32_t rs, uint32_t rt)
{
uint32_t rd, lo, hi;
uint64_t r;
__asm__ __volatile__ (
" multu %0, %3, %4\n"
" mflo %1\n"
" mfhi %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt));
r = ((uint64_t)hi << 32) | (uint32_t)lo;
assert((uint64_t)rs * rt == r);
assert(rd == lo);
return r;
}
static uint64_t multu1(uint32_t rs, uint32_t rt)
{
uint32_t rd, lo, hi;
uint64_t r;
__asm__ __volatile__ (
" multu1 %0, %3, %4\n"
" mflo1 %1\n"
" mfhi1 %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt));
r = ((uint64_t)hi << 32) | (uint32_t)lo;
assert((uint64_t)rs * rt == r);
assert(rd == lo);
return r;
}
static uint64_t multu_variants(uint32_t rs, uint32_t rt)
{
uint64_t rd = multu(rs, rt);
uint64_t rd1 = multu1(rs, rt);
assert(rd == rd1);
return rd;
}
int main()
{
assert(multu_variants(17, 19) == 323);
assert(multu_variants(77773, 99991) == 7776600043);
assert(multu_variants(12207031, 305175781) == 3725290219116211);
assert(multu_variants(0x80000000U, 0x7FFFFFFF) == 0x3FFFFFFF80000000);
assert(multu_variants(0x80000000U, 0x80000000U) == 0x4000000000000000);
assert(multu_variants(0xFFFFFFFFU, 0xFFFFFFFFU) == 0xFFFFFFFE00000001U);
return 0;
}
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