#error Temporarily omitting, as it only times out in any case

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#define __1D_WORK_GROUP
#define __1D_GRID
#include <opencl.h>


//__axiom(get_global_size(0) == 64);
__axiom(get_local_size(0) == 64);
__axiom(get_num_groups(0) == 1);

// This is 2 PI / 1024
#define ANGLE 0x1.921fb6p-8F

// Return sin and cos of -2*pi*i/1024
static __attribute__((always_inline)) float
k_sincos(int i, float *cretp)
{
    if (i > 512)
	i -= 1024;

    float x = i * -ANGLE;
    *cretp = native_cos(x);
    return native_sin(x);
}

static __attribute__((always_inline)) float4
k_sincos4(int4 i, float4 *cretp)
{
    i -= (i > 512) & 1024;
    float4 x = convert_float4(i) * -ANGLE;
    *cretp = native_cos(x);
    return native_sin(x);
}

// Twiddle factor stuff
#define TWGEN(I,C,S) \
    float C; \
    float S = k_sincos(tbase * I, &C)

#define TW4GEN(I,C,S) \
    float4 C; \
    float4 S = k_sincos4(tbase * I, &C)

#define TWAPPLY(ZR, ZI, C, S) \
    do { \
	float4 __r = C * ZR - S * ZI; \
	ZI = C * ZI + S * ZR; \
	ZR = __r; \
    } while (0)

# define TW4IDDLE4() \
    do { \
        TW4GEN(1, c1, s1); \
        TWAPPLY(zr1, zi1, c1, s1); \
        TW4GEN(2, c2, s2); \
        TWAPPLY(zr2, zi2, c2, s2); \
        TW4GEN(3, c3, s3); \
        TWAPPLY(zr3, zi3, c3, s3); \
    } while (0)
    
# define TWIDDLE4() \
    do { \
        TWGEN(1, c1, s1); \
        TWAPPLY(zr1, zi1, c1, s1); \
        TWGEN(2, c2, s2); \
        TWAPPLY(zr2, zi2, c2, s2); \
        TWGEN(3, c3, s3); \
        TWAPPLY(zr3, zi3, c3, s3); \
    } while (0)

// 4 point FFT
#define FFT4() \
    do { \
        float4 ar0 = zr0 + zr2; \
        float4 ar2 = zr1 + zr3; \
        float4 br0 = ar0 + ar2; \
        float4 br1 = zr0 - zr2; \
        float4 br2 = ar0 - ar2; \
        float4 br3 = zr1 - zr3; \
        float4 ai0 = zi0 + zi2; \
        float4 ai2 = zi1 + zi3; \
        float4 bi0 = ai0 + ai2; \
        float4 bi1 = zi0 - zi2; \
        float4 bi2 = ai0 - ai2; \
        float4 bi3 = zi1 - zi3; \
        zr0 = br0; \
        zi0 = bi0; \
        zr1 = br1 + bi3; \
        zi1 = bi1 - br3; \
        zr3 = br1 - bi3; \
        zi3 = br3 + bi1; \
        zr2 = br2; \
        zi2 = bi2; \
    } while (0)

// First pass of 1K FFT
static __attribute__((always_inline)) void
kfft_pass1(uint me,
	    const __global float *greal, const __global float *gimag,
	    __local float *lds)
{
    const __global float4 *gp;
    __local float *lp;

    // Pull in transform data
    gp = (const __global float4 *)(greal + (me << 2));
    float4 zr0 = gp[0*64];
    float4 zr1 = gp[1*64];
    float4 zr2 = gp[2*64];
    float4 zr3 = gp[3*64];

    gp = (const __global float4 *)(gimag + (me << 2));
    float4 zi0 = gp[0*64];
    float4 zi1 = gp[1*64];
    float4 zi2 = gp[2*64];
    float4 zi3 = gp[3*64];
    FFT4();

    int4 tbase = (int)(me << 2) + (int4)(0, 1, 2, 3);
    TW4IDDLE4();

    // Save registers
    // Note that this pointer is not aligned enough to be cast to a float4*
    lp = lds + ((me << 2) + (me >> 3));

    lp[0] = zr0.x;
    lp[1] = zr0.y;
    lp[2] = zr0.z;
    lp[3] = zr0.w;
    lp = lp + 66*4;

    lp[0] = zr1.x;
    lp[1] = zr1.y;
    lp[2] = zr1.z;
    lp[3] = zr1.w;
    lp = lp + 66*4;

    lp[0] = zr2.x;
    lp[1] = zr2.y;
    lp[2] = zr2.z;
    lp[3] = zr2.w;
    lp = lp + 66*4;

    lp[0] = zr3.x;
    lp[1] = zr3.y;
    lp[2] = zr3.z;
    lp[3] = zr3.w;
    lp = lp + 66*4;

    // Imaginary part
    lp[0] = zi0.x;
    lp[1] = zi0.y;
    lp[2] = zi0.z;
    lp[3] = zi0.w;
    lp = lp + 66*4;

    lp[0] = zi1.x;
    lp[1] = zi1.y;
    lp[2] = zi1.z;
    lp[3] = zi1.w;
    lp = lp + 66*4;

    lp[0] = zi2.x;
    lp[1] = zi2.y;
    lp[2] = zi2.z;
    lp[3] = zi2.w;
    lp = lp + 66*4;

    lp[0] = zi3.x;
    lp[1] = zi3.y;
    lp[2] = zi3.z;
    lp[3] = zi3.w;

    barrier(CLK_LOCAL_MEM_FENCE);
}

// Second pass of 1K FFT
static __attribute__((always_inline)) void
kfft_pass2(uint me, __local float *lds)
{
    __local float *lp;

    // Load registers
    lp = lds + (me + (me >> 5));

    float4 zr0, zr1, zr2, zr3;

    zr0.x = lp[0*66];
    zr1.x = lp[1*66];
    zr2.x = lp[2*66];
    zr3.x = lp[3*66];
    lp = lp + 66*4;

    zr0.y = lp[0*66];
    zr1.y = lp[1*66];
    zr2.y = lp[2*66];
    zr3.y = lp[3*66];
    lp = lp + 66*4;

    zr0.z = lp[0*66];
    zr1.z = lp[1*66];
    zr2.z = lp[2*66];
    zr3.z = lp[3*66];
    lp = lp + 66*4;

    zr0.w = lp[0*66];
    zr1.w = lp[1*66];
    zr2.w = lp[2*66];
    zr3.w = lp[3*66];
    lp = lp + 66*4;

    float4 zi0, zi1, zi2, zi3;

    zi0.x = lp[0*66];
    zi1.x = lp[1*66];
    zi2.x = lp[2*66];
    zi3.x = lp[3*66];
    lp = lp + 66*4;

    zi0.y = lp[0*66];
    zi1.y = lp[1*66];
    zi2.y = lp[2*66];
    zi3.y = lp[3*66];
    lp = lp + 66*4;

    zi0.z = lp[0*66];
    zi1.z = lp[1*66];
    zi2.z = lp[2*66];
    zi3.z = lp[3*66];
    lp = lp + 66*4;

    zi0.w = lp[0*66];
    zi1.w = lp[1*66];
    zi2.w = lp[2*66];
    zi3.w = lp[3*66];

    // Transform and twiddle
    FFT4();

    int tbase = (int)(me << 2);
    TWIDDLE4();

    barrier(CLK_LOCAL_MEM_FENCE);

    // Store registers
    lp = lds + ((me << 2) + (me >> 3));

    lp[0] = zr0.x;
    lp[1] = zr1.x;
    lp[2] = zr2.x;
    lp[3] = zr3.x;
    lp = lp + 66*4;

    lp[0] = zr0.y;
    lp[1] = zr1.y;
    lp[2] = zr2.y;
    lp[3] = zr3.y;
    lp = lp + 66*4;

    lp[0] = zr0.z;
    lp[1] = zr1.z;
    lp[2] = zr2.z;
    lp[3] = zr3.z;
    lp = lp + 66*4;

    lp[0] = zr0.w;
    lp[1] = zr1.w;
    lp[2] = zr2.w;
    lp[3] = zr3.w;
    lp = lp + 66*4;

    // Imaginary part
    lp[0] = zi0.x;
    lp[1] = zi1.x;
    lp[2] = zi2.x;
    lp[3] = zi3.x;
    lp = lp + 66*4;

    lp[0] = zi0.y;
    lp[1] = zi1.y;
    lp[2] = zi2.y;
    lp[3] = zi3.y;
    lp = lp + 66*4;

    lp[0] = zi0.z;
    lp[1] = zi1.z;
    lp[2] = zi2.z;
    lp[3] = zi3.z;
    lp = lp + 66*4;

    lp[0] = zi0.w;
    lp[1] = zi1.w;
    lp[2] = zi2.w;
    lp[3] = zi3.w;

    barrier(CLK_LOCAL_MEM_FENCE);
}

// Third pass of 1K FFT
static __attribute__((always_inline)) void
kfft_pass3(uint me, __local float *lds)
{
    __local float *lp;

    // Load registers
    lp = lds + (me + (me >> 5));

    float4 zr0, zr1, zr2, zr3;

    zr0.x = lp[0*66];
    zr1.x = lp[1*66];
    zr2.x = lp[2*66];
    zr3.x = lp[3*66];
    lp = lp + 66*4;

    zr0.y = lp[0*66];
    zr1.y = lp[1*66];
    zr2.y = lp[2*66];
    zr3.y = lp[3*66];
    lp = lp + 66*4;

    zr0.z = lp[0*66];
    zr1.z = lp[1*66];
    zr2.z = lp[2*66];
    zr3.z = lp[3*66];
    lp = lp + 66*4;

    zr0.w = lp[0*66];
    zr1.w = lp[1*66];
    zr2.w = lp[2*66];
    zr3.w = lp[3*66];
    lp = lp + 66*4;

    float4 zi0, zi1, zi2, zi3;

    zi0.x = lp[0*66];
    zi1.x = lp[1*66];
    zi2.x = lp[2*66];
    zi3.x = lp[3*66];
    lp = lp + 66*4;

    zi0.y = lp[0*66];
    zi1.y = lp[1*66];
    zi2.y = lp[2*66];
    zi3.y = lp[3*66];
    lp = lp + 66*4;

    zi0.z = lp[0*66];
    zi1.z = lp[1*66];
    zi2.z = lp[2*66];
    zi3.z = lp[3*66];
    lp = lp + 66*4;

    zi0.w = lp[0*66];
    zi1.w = lp[1*66];
    zi2.w = lp[2*66];
    zi3.w = lp[3*66];

    // Transform and twiddle
    FFT4();

    int tbase = (int)((me >> 2) << 4);
    TWIDDLE4();

    barrier(CLK_LOCAL_MEM_FENCE);

    // Save registers
    lp = lds + me;

    lp[0*66] = zr0.x;
    lp[1*66] = zr0.y;
    lp[2*66] = zr0.z;
    lp[3*66] = zr0.w;
    lp = lp + 66*4;

    lp[0*66] = zr1.x;
    lp[1*66] = zr1.y;
    lp[2*66] = zr1.z;
    lp[3*66] = zr1.w;
    lp = lp + 66*4;

    lp[0*66] = zr2.x;
    lp[1*66] = zr2.y;
    lp[2*66] = zr2.z;
    lp[3*66] = zr2.w;
    lp = lp + 66*4;

    lp[0*66] = zr3.x;
    lp[1*66] = zr3.y;
    lp[2*66] = zr3.z;
    lp[3*66] = zr3.w;
    lp = lp + 66*4;

    // Imaginary part
    lp[0*66] = zi0.x;
    lp[1*66] = zi0.y;
    lp[2*66] = zi0.z;
    lp[3*66] = zi0.w;
    lp = lp + 66*4;

    lp[0*66] = zi1.x;
    lp[1*66] = zi1.y;
    lp[2*66] = zi1.z;
    lp[3*66] = zi1.w;
    lp = lp + 66*4;

    lp[0*66] = zi2.x;
    lp[1*66] = zi2.y;
    lp[2*66] = zi2.z;
    lp[3*66] = zi2.w;
    lp = lp + 66*4;

    lp[0*66] = zi3.x;
    lp[1*66] = zi3.y;
    lp[2*66] = zi3.z;
    lp[3*66] = zi3.w;

    barrier(CLK_LOCAL_MEM_FENCE);
}

// Fourth pass of 1K FFT
static __attribute__((always_inline)) void
kfft_pass4(uint me, __local float *lds)
{
    __local float *lp;

    // Load registers
    lp = lds + ((me & 0x3) + ((me >> 2) & 0x3)*(66*4) + ((me >> 4) << 2));

    float4 zr0, zr1, zr2, zr3;

    zr0.x = lp[0*66];
    zr0.y = lp[1*66];
    zr0.z = lp[2*66];
    zr0.w = lp[3*66];
    lp = lp + 16;

    zr1.x = lp[0*66];
    zr1.y = lp[1*66];
    zr1.z = lp[2*66];
    zr1.w = lp[3*66];
    lp = lp + 16;

    zr2.x = lp[0*66];
    zr2.y = lp[1*66];
    zr2.z = lp[2*66];
    zr2.w = lp[3*66];
    lp = lp + 16;

    zr3.x = lp[0*66];
    zr3.y = lp[1*66];
    zr3.z = lp[2*66];
    zr3.w = lp[3*66];
    lp = lp + 66*4*4 - 3*16;

    float4 zi0, zi1, zi2, zi3;

    zi0.x = lp[0*66];
    zi0.y = lp[1*66];
    zi0.z = lp[2*66];
    zi0.w = lp[3*66];
    lp = lp + 16;

    zi1.x = lp[0*66];
    zi1.y = lp[1*66];
    zi1.z = lp[2*66];
    zi1.w = lp[3*66];
    lp = lp + 16;

    zi2.x = lp[0*66];
    zi2.y = lp[1*66];
    zi2.z = lp[2*66];
    zi2.w = lp[3*66];
    lp = lp + 16;

    zi3.x = lp[0*66];
    zi3.y = lp[1*66];
    zi3.z = lp[2*66];
    zi3.w = lp[3*66];

    // Transform and twiddle
    FFT4();

    int tbase = (int)((me >> 4) << 6);
    TWIDDLE4();

    barrier(CLK_LOCAL_MEM_FENCE);

    // Save registers in conflict free manner
    lp = lds + me;

    lp[0*68] = zr0.x;
    lp[1*68] = zr0.y;
    lp[2*68] = zr0.z;
    lp[3*68] = zr0.w;
    lp = lp + 68*4;

    lp[0*68] = zr1.x;
    lp[1*68] = zr1.y;
    lp[2*68] = zr1.z;
    lp[3*68] = zr1.w;
    lp = lp + 68*4;

    lp[0*68] = zr2.x;
    lp[1*68] = zr2.y;
    lp[2*68] = zr2.z;
    lp[3*68] = zr2.w;
    lp = lp + 68*4;

    lp[0*68] = zr3.x;
    lp[1*68] = zr3.y;
    lp[2*68] = zr3.z;
    lp[3*68] = zr3.w;
    lp = lp + 68*4;

    // Imaginary part
    lp[0*68] = zi0.x;
    lp[1*68] = zi0.y;
    lp[2*68] = zi0.z;
    lp[3*68] = zi0.w;
    lp = lp + 68*4;

    lp[0*68] = zi1.x;
    lp[1*68] = zi1.y;
    lp[2*68] = zi1.z;
    lp[3*68] = zi1.w;
    lp = lp + 68*4;

    lp[0*68] = zi2.x;
    lp[1*68] = zi2.y;
    lp[2*68] = zi2.z;
    lp[3*68] = zi2.w;
    lp = lp + 68*4;

    lp[0*68] = zi3.x;
    lp[1*68] = zi3.y;
    lp[2*68] = zi3.z;
    lp[3*68] = zi3.w;

    barrier(CLK_LOCAL_MEM_FENCE);
}

// Fifth and last pass of 1K FFT
static __attribute__((always_inline)) void
kfft_pass5(uint me,
	   const __local float *lds,
	   __global float *greal, __global float *gimag)
{
    const __local float *lp;

    // Load registers
    lp = lds + ((me & 0xf) + (me >> 4)*(68*4));

    float4 zr0, zr1, zr2, zr3;

    zr0.x = lp[0*68];
    zr0.y = lp[1*68];
    zr0.z = lp[2*68];
    zr0.w = lp[3*68];
    lp = lp + 16;

    zr1.x = lp[0*68];
    zr1.y = lp[1*68];
    zr1.z = lp[2*68];
    zr1.w = lp[3*68];
    lp = lp + 16;

    zr2.x = lp[0*68];
    zr2.y = lp[1*68];
    zr2.z = lp[2*68];
    zr2.w = lp[3*68];
    lp = lp + 16;

    zr3.x = lp[0*68];
    zr3.y = lp[1*68];
    zr3.z = lp[2*68];
    zr3.w = lp[3*68];

    lp = lp + 68*4*4 - 3*16;

    float4 zi0, zi1, zi2, zi3;

    zi0.x = lp[0*68];
    zi0.y = lp[1*68];
    zi0.z = lp[2*68];
    zi0.w = lp[3*68];
    lp = lp + 16;

    zi1.x = lp[0*68];
    zi1.y = lp[1*68];
    zi1.z = lp[2*68];
    zi1.w = lp[3*68];
    lp = lp + 16;

    zi2.x = lp[0*68];
    zi2.y = lp[1*68];
    zi2.z = lp[2*68];
    zi2.w = lp[3*68];
    lp = lp + 16;

    zi3.x = lp[0*68];
    zi3.y = lp[1*68];
    zi3.z = lp[2*68];
    zi3.w = lp[3*68];

    // Transform
    FFT4();
    // Save result
    __global float4 *gp = (__global float4 *)(greal + (me << 2));
    gp[0*64] = zr0;
    gp[1*64] = zr1;
    gp[2*64] = zr2;
    gp[3*64] = zr3;

    gp = (__global float4 *)(gimag + (me << 2));
    gp[0*64] = zi0;
    gp[1*64] = zi1;
    gp[2*64] = zi2;
    gp[3*64] = zi3;
}

// Distance between first real element of successive 1K vectors
// It must be >= 1024, and a multiple of 4
#define VSTRIDE (1024+0)

// Performs a 1K complex FFT with every 64 global ids.
// Each vector is a multiple of VSTRIDE from the first
// Number of global ids must be a multiple of 64, e.g. 1024*64
//
//   greal - pointer to input and output real part of data
//   gimag - pointer to input and output imaginary part of data
__kernel void
kfft(__global float *greal, __global float *gimag)
{
    // This is 8704 bytes
    __local float lds[68*4*4*2];

    //__global float *gr;
    //__global float *gi;
    uint gid = get_global_id(0);
    uint me = gid & 0x3fU;
    uint dg = (gid >> 6) * VSTRIDE;

    greal = greal + dg;
    gimag = gimag + dg;

    kfft_pass1(me, greal, gimag, lds);
    kfft_pass2(me, lds);
    kfft_pass3(me, lds);
    kfft_pass4(me, lds);
    kfft_pass5(me, lds, greal, gimag);
}

