/*
    Copyright (c) 2005-2020 Intel Corporation

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

#include "tbb/tbb_config.h"
#include "harness.h"

// Skip the test if no interoperability with cilkrts
#define __TBB_CILK_INTEROP   (__TBB_SURVIVE_THREAD_SWITCH && __INTEL_COMPILER>=1200)
// The compiler does not add "-lcilkrts" linker option on some linux systems
#define CILK_LINKAGE_BROKEN  (__linux__ && __GNUC__<4 && __INTEL_COMPILER_BUILD_DATE <= 20110427)
// In U4, cilkrts incorrectly sends the interop notifications to TBB
#define CILK_NOTIFICATIONS_BROKEN ( __INTEL_COMPILER_BUILD_DATE == 20110427 )

#if __TBB_CILK_INTEROP && !CILK_LINKAGE_BROKEN && !CILK_NOTIFICATIONS_BROKEN

static const int N = 14;
static const int P_outer = 4;
static const int P_nested = 2;

#include <cilk/cilk.h>
#include <cilk/cilk_api.h>
#define private public
#include "tbb/task.h"
#undef private
#include "tbb/task_scheduler_init.h"
#include <cstdio>
#include <cassert>

enum tbb_sched_injection_mode_t {
    tbbsched_none = 0,
    tbbsched_explicit_only = 1,
    tbbsched_auto_only = 2,
    tbbsched_mixed = 3
};

tbb_sched_injection_mode_t g_sim = tbbsched_none;

bool g_sandwich = false; // have to be declare before #include "test_cilk_common.h"
#include "test_cilk_common.h"

// A time delay routine
void Delay( int n ) {
    static volatile int Global;
    for( int k=0; k<10000; ++k )
        for( int i=0; i<n; ++i )
            ++Global;
}

int SerialFib( int n ) {
    int a=0, b=1;
    for( int i=0; i<n; ++i ) {
        b += a;
        a = b-a;
    }
    return a;
}

int F = SerialFib(N);

int Fib ( int n ) {
    if( n < 2 ) {
        if ( g_sim ) {
            tbb::task_scheduler_init tsi(P_nested);
        }
        return n;
    } else {
        tbb::task_scheduler_init *tsi = NULL;
        tbb::task *cur = NULL;
        if ( g_sim ) {
            if ( n % 2 == 0 ) {
                if ( g_sim == tbbsched_auto_only || (g_sim == tbbsched_mixed && n % 4 == 0) ) {
                    // Trigger TBB scheduler auto-initialization
                    cur = &tbb::task::self();
                }
                else {
                    ASSERT ( g_sim == tbbsched_explicit_only || (g_sim == tbbsched_mixed && n % 4 != 0), NULL );
                    // Initialize TBB scheduler explicitly
                    tsi = new tbb::task_scheduler_init(P_nested);
                }
            }
        }
        int x, y;
        x = cilk_spawn Fib(n-2);
        y = cilk_spawn Fib(n-1);
        cilk_sync;
        if ( tsi )
            delete tsi;
        return x+y;
    }
}

void RunCilkOnly ( tbb_sched_injection_mode_t sim ) {
    g_sim = sim;
    int m = Fib(N);
    ASSERT( m == F, NULL );
}

struct FibBody : NoAssign, Harness::NoAfterlife {
    void operator() ( int ) const {
        int m = Fib(N);
        ASSERT( m == F, NULL );
    }
};

void RunCilkOnlyConcurrently ( tbb_sched_injection_mode_t sim ) {
    g_sim = sim;
    NativeParallelFor( P_outer, FibBody() );
}

void RunSandwich( bool sandwich ) {
    g_sandwich = sandwich;
    tbb::task_scheduler_init init(P_outer);
    int m = TBB_Fib(N);
    ASSERT( g_sandwich == sandwich, "Memory corruption detected" );
    ASSERT( m == F, NULL );
}

int TestMain () {
    for ( int i = 0; i < 100; ++i )
        RunCilkOnlyConcurrently( tbbsched_none );
    RunCilkOnly( tbbsched_none );
    RunCilkOnly( tbbsched_explicit_only );
    RunCilkOnly( tbbsched_auto_only );
    RunCilkOnly( tbbsched_mixed );
    RunSandwich( false );
    for ( int i = 0; i < 10; ++i )
        RunSandwich( true );
    __cilkrts_end_cilk();
    return Harness::Done;
}

#else /* !__TBB_CILK_INTEROP */

int TestMain () {
    return Harness::Skipped;
}

#endif /* !__TBB_CILK_INTEROP */
