/*"Fixed point" means you use ints that are scaled by a value. A common example would be using number of pennies instead of dollars with a float. Fixed-point used to be much faster, but modern processors do well with floats. It also depends on the compiler and my compiler is poor with floats. I often use 64-bit ints with upper 32-bits as int and lower 32-bits as fraction. See ::/Demo/SubIntAccess.HC for how to access upper or lower 32-bits. For a complete lst of nonstandard compiler features, see ::/Doc/HolyC.DD. */ U0 Main() { F64 t0,f_sum=0,f_val; I64 i ,i_sum=0,i_val; i_val= 2.0000002 *0x100000000; t0=tS; for (i=1000000000;i;i--) i_sum+=i_val; "Int Sum\t\t:%.9f Time:%7.3fs\n",i_sum/ToF64(0x100000000),tS-t0; f_val= 2.0000002; t0=tS; for (i=1000000000;i;i--) f_sum+=f_val; "Float Sum\t:%.9f Time:%7.3fs\n",f_sum,tS-t0; '\n'; } U0 DoIt2() { I64 i=0x123456789ABCDEF0; "i\t\t=%X\n",i; "i&0xFFFFFFFF\t=%X\n",i&0xFFFFFFFF; "i>>32\t\t=%X\n",i>>32; /* Standard int types are declared with a special compiler feature which allows a structure to be accessed as a whole. That's why the i variable can be accessed normally in addition to structure member access I64. The actual intrinsic compiler type is U64i. public U64i union I64 { I8i i8[8]; U8i u8[8]; I16 i16[4]; U16 u16[4]; I32 i32[2]; U32 u32[2]; }; It's not quite as great as it seems because the compiler decides it cannot place i into a reg, so there is a penalty. For a complete lst of nonstandard compiler features, see ::/Doc/HolyC.DD. */ "i.u32[0]\t=%X\n",i.u32[0]; "i.u32[1]\t=%X\n",i.u32[1]; } CPURep; Main; DoIt2; //See ::/Demo/Lectures/FixedPointAdvanced.HC /*Program Output 16 Cores 3.500GHz Int Sum :2000000199.768690240 Time: 0.803s Float Sum :2000000225.656127040 Time: 3.615s i =123456789ABCDEF0 i&0xFFFFFFFF =9ABCDEF0 i>>32 =12345678 i.u32[0] =9ABCDEF0 i.u32[1] =12345678 */