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/*
* Test R5900-specific three-operand MULT and MULT1.
*/
#include <stdio.h>
#include <inttypes.h>
#include <assert.h>
static int64_t mult(int32_t rs, int32_t rt)
{
int32_t rd, lo, hi;
int64_t r;
__asm__ __volatile__ (
" mult %0, %3, %4\n"
" mflo %1\n"
" mfhi %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt));
r = ((int64_t)hi << 32) | (uint32_t)lo;
assert((int64_t)rs * rt == r);
assert(rd == lo);
return r;
}
static int64_t mult1(int32_t rs, int32_t rt)
{
int32_t rd, lo, hi;
int64_t r;
__asm__ __volatile__ (
" mult1 %0, %3, %4\n"
" mflo1 %1\n"
" mfhi1 %2\n"
: "=r" (rd), "=r" (lo), "=r" (hi)
: "r" (rs), "r" (rt));
r = ((int64_t)hi << 32) | (uint32_t)lo;
assert((int64_t)rs * rt == r);
assert(rd == lo);
return r;
}
static int64_t mult_variants(int32_t rs, int32_t rt)
{
int64_t rd = mult(rs, rt);
int64_t rd1 = mult1(rs, rt);
assert(rd == rd1);
return rd;
}
static void verify_mult_negations(int32_t rs, int32_t rt, int64_t expected)
{
assert(mult_variants(rs, rt) == expected);
assert(mult_variants(-rs, rt) == -expected);
assert(mult_variants(rs, -rt) == -expected);
assert(mult_variants(-rs, -rt) == expected);
}
int main()
{
verify_mult_negations(17, 19, 323);
verify_mult_negations(77773, 99991, 7776600043);
verify_mult_negations(12207031, 305175781, 3725290219116211);
assert(mult_variants(-0x80000000, 0x7FFFFFFF) == -0x3FFFFFFF80000000);
assert(mult_variants(-0x80000000, -0x7FFFFFFF) == 0x3FFFFFFF80000000);
assert(mult_variants(-0x80000000, -0x80000000) == 0x4000000000000000);
return 0;
}
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