TGP:Index

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Revision as of 16:57, 11 February 2007 by Galibert (talk | contribs)

ALU operations

ALU operations seem to be encoded in 6 bits. There are some discrepancies compared to the datasheet:

  • the datasheet talks of op-a and op-b operations. These look like op-a operations, and we have no clue what the op-b looks like.
  • the shift operations are not supposed to be there but should be opcodes by themselves
Value Type Operation Value Type Operation Value Type Operation Value Type Operation
00 000000 nop 10 010000 f32 p = a * b 20 100000 ? ? 30 110000 int a = a >> c
01 000001 nop 11 010001 f32 p = a * b 21 100001 ? ? 31 110001 int a = a >> d
02 000010 int c = c & a 12 010010 f32 c = c + p, p = a * b 22 100010 ? ? 32 110010 ? ?
03 000011 int d = d & a 13 010011 f32 d = d + p, p = a * b 23 100011 ? ? 33 110011 ? ?
04 000100 ? ? 14 010100 f32 c = c - p, p = a * b 24 100100 ? ? 34 110100 i24 c = c + a
05 000101 ? ? 15 010101 f32 d = d - p, p = a * b 25 100101 ? ? 35 110101 i24 d = d + a
06 000110 ? ? 16 010110 ? ? 26 100110 ? ? 36 110110 i24 c = c - a
07 000111 ? ? 17 010111 ? ? 27 100111 ? ? 37 110111 i24 d = d - a
08 001000 ? ? 18 011000 f32 c = a + b 28 101000 f32 c = a - b 38 111000 ? ?
09 001001 ? ? 19 011001 f32 d = a + b 29 101001 f32 d = a - b 39 111001 ? ?
0a 001010 ? ? 1a 011010 f32 c = p, p = a * b 2a 101010 ? ? 3a 111010 ? ?
0b 001011 ? ? 1b 011011 f32 d = p, p = a * b 2b 101011 ? ? 3b 111011 ? ?
0c 001100 f32 c = c + a 1c 011100 ? ? 2c 101100 ? ? 3c 111100 ? ?
0d 001101 f32 d = d + a 1d 011101 ? ? 2d 101101 ? ? 3d 111101 ? ?
0e 001110 f32 c = c - a 1e 011110 ? ? 2e 101110 int a = a << c 3e 111110 ? ?
0f 001111 f32 d = d - a 1f 011111 ? ? 2f 101111 int a = a << d 3f 111111 ? ?

Known missing: xor, not, neg, abs, comparisons (sub)