Changeset 1975

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Timestamp:
03/25/12 11:23:24 (14 months ago)
Author:
cameron
Message:

Defining carry_t; allows different storage represenations for carries.

Files:
1 modified

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Removed

  • trunk/lib/bitblock128.hpp

    r1950 r1975  
    2323}; 
    2424 
    25 static IDISA_ALWAYS_INLINE void adc(bitblock128_t x, bitblock128_t y, bitblock128_t & carry, bitblock128_t & sum); 
    26 static IDISA_ALWAYS_INLINE void sbb(bitblock128_t x, bitblock128_t y, bitblock128_t & borrow, bitblock128_t & difference); 
    27 static IDISA_ALWAYS_INLINE void advance_with_carry(bitblock128_t cursor, bitblock128_t & carry, bitblock128_t & rslt); 
    28 static IDISA_ALWAYS_INLINE bool bitblock_has_bit(bitblock128_t arg1); 
    29 static IDISA_ALWAYS_INLINE void signbitmask(bitblock128_t & v); 
     25/* The type used to store a carry bit. */ 
     26typedef bitblock128_t carry_t; 
     27 
     28static IDISA_ALWAYS_INLINE bitblock128_t carry2bitblock(carry_t carry); 
     29static IDISA_ALWAYS_INLINE carry_t bitblock2carry(bitblock128_t carry); 
     30 
     31static IDISA_ALWAYS_INLINE void adc(bitblock128_t x, bitblock128_t y, carry_t & carry, bitblock128_t & sum); 
     32static IDISA_ALWAYS_INLINE void sbb(bitblock128_t x, bitblock128_t y, carry_t & borrow, bitblock128_t & difference); 
     33static IDISA_ALWAYS_INLINE void advance_with_carry(bitblock128_t cursor, carry_t & carry, bitblock128_t & rslt); 
     34 
    3035static IDISA_ALWAYS_INLINE bitblock128_t convert (uint64_t s); 
    3136static IDISA_ALWAYS_INLINE uint64_t convert (bitblock128_t v); 
    3237 
    33 IDISA_ALWAYS_INLINE void adc(bitblock128_t x, bitblock128_t y, bitblock128_t & carry, bitblock128_t & sum) 
     38static IDISA_ALWAYS_INLINE bitblock128_t carry2bitblock(carry_t carry) {  return carry;}  
     39static IDISA_ALWAYS_INLINE carry_t bitblock2carry(bitblock128_t carry) {  return carry;} 
     40 
     41IDISA_ALWAYS_INLINE void adc(bitblock128_t x, bitblock128_t y, carry_t & carry, bitblock128_t & sum) 
    3442{ 
    3543        bitblock128_t gen = simd_and(x, y); 
    3644        bitblock128_t prop = simd_or(x, y); 
    37         bitblock128_t partial = simd128<64>::add(simd128<64>::add(x, y), carry); 
     45        bitblock128_t partial = simd128<64>::add(simd128<64>::add(x, y), carry2bitblock(carry)); 
    3846        bitblock128_t c1 = simd128<128>::slli<64>(simd128<64>::srli<63>(simd_or(gen, simd_andc(prop, partial)))); 
    3947        sum = simd128<64>::add(c1, partial); 
    40         // carry = simd_and(hibitmask<bitblock128_t>(), simd_or(gen, simd_andc(prop, sum))); // TODO - set high bit carry via hibitmask 
    41         carry = simd128<128>::srli<127>(simd_or(gen, simd_andc(prop, sum))); // TODO - 
     48        carry = bitblock2carry(simd128<128>::srli<127>(simd_or(gen, simd_andc(prop, sum)))); 
    4249} 
    4350 
    44 IDISA_ALWAYS_INLINE void sbb(bitblock128_t x, bitblock128_t y, bitblock128_t & borrow, bitblock128_t & difference) 
     51IDISA_ALWAYS_INLINE void sbb(bitblock128_t x, bitblock128_t y, carry_t & borrow, bitblock128_t & difference) 
    4552{ 
    4653        bitblock128_t gen = simd_andc(y, x); 
    4754        bitblock128_t prop = simd_not(simd_xor(x, y)); 
    48         bitblock128_t partial = simd128<64>::sub(simd128<64>::sub(x, y), borrow); 
     55        bitblock128_t partial = simd128<64>::sub(simd128<64>::sub(x, y), carry2bitblock(borrow)); 
    4956        bitblock128_t b1 = simd128<128>::slli<64>(simd128<64>::srli<63>(simd_or(gen, simd_and(prop, partial)))); 
    5057        difference = simd128<64>::sub(partial, b1); 
    51         // borrow = simd_and(hibitmask<bitblock128_t>, simd_or(gen, simd_and(prop, difference))); // TODO - set high bit carry via hibitmask 
    52         borrow = simd128<128>::srli<127>(simd_or(gen, simd_and(prop, difference))); 
     58        borrow = bitblock2carry(simd128<128>::srli<127>(simd_or(gen, simd_and(prop, difference)))); 
    5359} 
    5460 
    55 IDISA_ALWAYS_INLINE void advance_with_carry(bitblock128_t cursor, bitblock128_t & carry, bitblock128_t & rslt) 
     61IDISA_ALWAYS_INLINE void advance_with_carry(bitblock128_t cursor, carry_t & carry, bitblock128_t & rslt) 
    5662{ 
    5763bitblock128_t shift_out = simd128<64>::srli<63>(cursor); 
    58 bitblock128_t low_bits = esimd128<64>::mergel(shift_out, carry); 
    59 // carry = simd_and(hibitmask<bitblock128_t>, cursor); 
    60 carry = simd128<128>::srli<64>(shift_out);                                              // carry - accumlated 127 shift right locical shift of cursor 
     64bitblock128_t low_bits = esimd128<64>::mergel(shift_out, carry2bitblock(carry)); 
     65carry = bitblock2carry(simd128<128>::srli<64>(shift_out)); 
    6166rslt = simd_or(simd128<64>::add(cursor, cursor), low_bits); 
    62 } 
    63  
    64 IDISA_ALWAYS_INLINE void signbitmask(bitblock128_t & v) 
    65 { 
    66         v =  simd128<128>::slli<127>(simd128<128>::constant<1>()); 
    6767} 
    6868