// SPDX-License-Identifier: GPL-2.0
#undef _GNU_SOURCE
#define _GNU_SOURCE 1
#undef __USE_GNU
#define __USE_GNU 1
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <fenv.h>

unsigned long long res64 = -1;
unsigned int res32 = -1;
unsigned short res16 = -1;

int test(void)
{
        int ex;

        feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        asm volatile ("\n"
        "       fld1""\n"
        "       fisttps res16""\n"
        "       fld1""\n"
        "       fisttpl res32""\n"
        "       fld1""\n"
        "       fisttpll res64""\n"
        : : : "memory"
        );
        if (res16 != 1 || res32 != 1 || res64 != 1) {
                printf("[BAD]\tfisttp 1\n");
                return 1;
        }
        ex = fetestexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        if (ex != 0) {
                printf("[BAD]\tfisttp 1: wrong exception state\n");
                return 1;
        }

        feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        asm volatile ("\n"
        "       fldpi""\n"
        "       fisttps res16""\n"
        "       fldpi""\n"
        "       fisttpl res32""\n"
        "       fldpi""\n"
        "       fisttpll res64""\n"
        : : : "memory"
        );
        if (res16 != 3 || res32 != 3 || res64 != 3) {
                printf("[BAD]\tfisttp pi\n");
                return 1;
        }
        ex = fetestexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        if (ex != FE_INEXACT) {
                printf("[BAD]\tfisttp pi: wrong exception state\n");
                return 1;
        }

        feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        asm volatile ("\n"
        "       fldpi""\n"
        "       fchs""\n"
        "       fisttps res16""\n"
        "       fldpi""\n"
        "       fchs""\n"
        "       fisttpl res32""\n"
        "       fldpi""\n"
        "       fchs""\n"
        "       fisttpll res64""\n"
        : : : "memory"
        );
        if (res16 != 0xfffd || res32 != 0xfffffffd || res64 != 0xfffffffffffffffdULL) {
                printf("[BAD]\tfisttp -pi\n");
                return 1;
        }
        ex = fetestexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        if (ex != FE_INEXACT) {
                printf("[BAD]\tfisttp -pi: wrong exception state\n");
                return 1;
        }

        feclearexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        asm volatile ("\n"
        "       fldln2""\n"
        "       fisttps res16""\n"
        "       fldln2""\n"
        "       fisttpl res32""\n"
        "       fldln2""\n"
        "       fisttpll res64""\n"
        : : : "memory"
        );
        /* Test truncation to zero (round-to-nearest would give 1 here) */
        if (res16 != 0 || res32 != 0 || res64 != 0) {
                printf("[BAD]\tfisttp ln2\n");
                return 1;
        }
        ex = fetestexcept(FE_DIVBYZERO|FE_INEXACT|FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW);
        if (ex != FE_INEXACT) {
                printf("[BAD]\tfisttp ln2: wrong exception state\n");
                return 1;
        }

        return 0;
}

void sighandler(int sig)
{
        printf("[FAIL]\tGot signal %d, exiting\n", sig);
        exit(1);
}

int main(int argc, char **argv, char **envp)
{
        int err = 0;

        /* SIGILL triggers on 32-bit kernels w/o fisttp emulation
         * when run with "no387 nofxsr". Other signals are caught
         * just in case.
         */
        signal(SIGILL, sighandler);
        signal(SIGFPE, sighandler);
        signal(SIGSEGV, sighandler);

        printf("[RUN]\tTesting fisttp instructions\n");
        err |= test();
        if (!err)
                printf("[OK]\tfisttp\n");
        else
                printf("[FAIL]\tfisttp errors: %d\n", err);

        return err;
}