demo data generator scratchpad

gendemodata.js

// =============================================================================
//  ENCODERS (CPU — for demo generation)
// =============================================================================

function fp16ToF32(u16){let s=(u16>>15)&1,e=(u16>>10)&0x1F,m=u16&0x3FF;if(e===0)return(s?-1:1)*Math.pow(2,-14)*(m/1024);if(e===31)return m?NaN:(s?-Infinity:Infinity);return(s?-1:1)*Math.pow(2,e-15)*(1+m/1024);}
function bf16ToF32(u16){let s=(u16>>15)&1,e=(u16>>7)&0xFF,m=u16&0x7F;if(e===0)return(s?-1:1)*Math.pow(2,-126)*(m/128);if(e===255)return m?NaN:(s?-Infinity:Infinity);return(s?-1:1)*Math.pow(2,e-127)*(1+m/128);}
function fp8E4M3ToF32(u8){let s=(u8>>7)&1,e=(u8>>3)&0xF,m=u8&0x7;if(e===0)return(s?-1:1)*Math.pow(2,-6)*(m/8);return(s?-1:1)*Math.pow(2,e-7)*(1+m/8);}
function fp8E5M2ToF32(u8){let s=(u8>>7)&1,e=(u8>>2)&0x1F,m=u8&0x3;if(e===0)return(s?-1:1)*Math.pow(2,-14)*(m/4);return(s?-1:1)*Math.pow(2,e-15)*(1+m/4);}
function fp4ToF32(u8){let s=(u8>>3)&1,e=(u8>>1)&0x3,m=u8&1;if(e===0)return(s?-1:1)*0.5*(m/2);return(s?-1:1)*Math.pow(2,e-1)*(1+m/2);}
function f32ToFp16(v){const b=new ArrayBuffer(4),f=new Float32Array(b),u=new Uint32Array(b);f[0]=v;const bits=u[0],s=(bits>>>31)&1,e=(bits>>>23)&0xFF,m=bits&0x7FFFFF;if(e===0xFF)return(s<<15)|0x7C00|(m?0x200:0);const ue=e-127;if(ue>15)return(s<<15)|0x7C00;if(ue<-14){const sh=-14-ue;if(sh>24)return s<<15;return(s<<15)|(((0x800000|m)>>(sh+13))&0x3FF);}return(s<<15)|((ue+15)<<10)|(m>>13);}
function f32ToBf16(v){const b=new ArrayBuffer(4),f=new Float32Array(b),u=new Uint32Array(b);f[0]=v;return u[0]>>>16;}
function f32ToFp8E4M3(v){let best=0,bd=Infinity;for(let b=0;b<256;b++){const d=fp8E4M3ToF32(b);if(!isFinite(d))continue;if(Math.abs(d-v)<bd){bd=Math.abs(d-v);best=b;}}return best;}
function f32ToFp8E5M2(v){let best=0,bd=Infinity;for(let b=0;b<256;b++){const d=fp8E5M2ToF32(b);if(!isFinite(d))continue;if(Math.abs(d-v)<bd){bd=Math.abs(d-v);best=b;}}return best;}
function f32ToFp4(v){let best=0,bd=Infinity;for(let b=0;b<16;b++){if(Math.abs(fp4ToF32(b)-v)<bd){bd=Math.abs(fp4ToF32(b)-v);best=b;}}return best;}
function normToFloat(n){return Math.atanh(2*Math.max(0.01,Math.min(0.99,n))-1);}

// =============================================================================
//  DEMO GENERATION (CPU)
// =============================================================================

function generateDemo(shape) {
    const f=state.format, isLE=state.isLE, num=100000;
    const is4Bit=f.endsWith('4'), isFloat=f.startsWith('fp')||f==='bf16';
    const byteStep=getByteStep(f);
    const buf=new ArrayBuffer(num*byteStep), v=new DataView(buf);
    let x=0.1,y=0,z=0; state.fileName="DEMO: "+shape.toUpperCase();

    for(let i=0;i<num;i++){
        let nx,ny,nz;
        if(shape==='lorenz'){let dx=10*(y-x),dy=x*(28-z)-y,dz=x*y-(8/3)*z;x+=dx*0.005;y+=dy*0.005;z+=dz*0.005;nx=(x+25)/50;ny=(y+30)/60;nz=z/50;}
        else{nx=Math.random();ny=Math.random();nz=Math.random();}
        nx=Math.max(0,Math.min(1,nx));ny=Math.max(0,Math.min(1,ny));nz=Math.max(0,Math.min(1,nz));
        const norms=[nx,ny,nz],off=i*byteStep;

        if(is4Bit){
            if(f==='uint4'){const nibs=norms.map(n=>Math.round(n*15));v.setUint8(off,(nibs[0]<<4)|nibs[1]);v.setUint8(off+1,nibs[2]<<4);}
            else if(f==='int4'){const nibs=norms.map(n=>{let s=Math.round(n*15)-8;return s<0?s+16:s;});v.setUint8(off,(nibs[0]<<4)|nibs[1]);v.setUint8(off+1,nibs[2]<<4);}
            else if(f==='fp4'){const nibs=norms.map(n=>f32ToFp4(normToFloat(n)));v.setUint8(off,(nibs[0]<<4)|nibs[1]);v.setUint8(off+1,nibs[2]<<4);}
        }else if(isFloat){
            const fv=norms.map(n=>normToFloat(n));
            if(f==='fp32'){for(let j=0;j<3;j++)v.setFloat32(off+j*4,fv[j],isLE);}
            else if(f==='fp64'){for(let j=0;j<3;j++)v.setFloat64(off+j*8,fv[j],isLE);}
            else if(f==='fp16'){for(let j=0;j<3;j++)v.setUint16(off+j*2,f32ToFp16(fv[j]),isLE);}
            else if(f==='bf16'){for(let j=0;j<3;j++)v.setUint16(off+j*2,f32ToBf16(fv[j]),isLE);}
            else if(f==='fp8_e4m3'){for(let j=0;j<3;j++)v.setUint8(off+j,f32ToFp8E4M3(fv[j]));}
            else if(f==='fp8_e5m2'){for(let j=0;j<3;j++)v.setUint8(off+j,f32ToFp8E5M2(fv[j]));}
        }else{
            if(f==='uint32'){for(let j=0;j<3;j++)v.setUint32(off+j*4,norms[j]*4294967295,isLE);}
            else if(f==='int32'){for(let j=0;j<3;j++)v.setInt32(off+j*4,norms[j]*4294967295-2147483648,isLE);}
            else if(f==='uint16'){for(let j=0;j<3;j++)v.setUint16(off+j*2,norms[j]*65535,isLE);}
            else if(f==='int16'){for(let j=0;j<3;j++)v.setInt16(off+j*2,norms[j]*65535-32768,isLE);}
            else if(f==='uint8'){for(let j=0;j<3;j++)v.setUint8(off+j,norms[j]*255);}
            else if(f==='int8'){for(let j=0;j<3;j++)v.setInt8(off+j,norms[j]*255-128);}
        }
    }
    state.file = null;
    state.fileSize = buf.byteLength;
    state.buffer = buf;
    runCompute();
}