1 | ; Project name : Assembly Library |
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2 | ; Description : Math related macros. |
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3 | %ifndef MATH_INC |
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4 | %define MATH_INC |
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5 | |
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6 | FALSE EQU 0 |
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7 | TRUE EQU 1 |
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8 | |
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9 | |
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10 | ;-------------------------------------------------------------------- |
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11 | ; MIN_U Unsigned comparison |
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12 | ; MIN_S Signed comparison |
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13 | ; Parameters: |
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14 | ; %1: Operand 1 |
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15 | ; %2: Operand 2 |
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16 | ; Returns: |
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17 | ; %1: Lesser operand |
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18 | ; Corrupts registers: |
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19 | ; Nothing |
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20 | ;-------------------------------------------------------------------- |
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21 | %macro MIN_U 2 |
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22 | cmp %1, %2 ; Is %1 smaller? |
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23 | jb %%Return ; If so, return |
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24 | mov %1, %2 ; Copy %2 to %1 |
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25 | ALIGN JUMP_ALIGN |
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26 | %%Return: |
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27 | %endmacro |
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28 | |
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29 | %macro MIN_S 2 |
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30 | cmp %1, %2 ; Is %1 smaller? |
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31 | jl %%Return ; If so, return |
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32 | mov %1, %2 ; Copy %2 to %1 |
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33 | ALIGN JUMP_ALIGN |
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34 | %%Return: |
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35 | %endmacro |
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36 | |
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37 | |
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38 | ;-------------------------------------------------------------------- |
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39 | ; MAX_U Unsigned comparison |
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40 | ; MAX_S Signed comparison |
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41 | ; Parameters: |
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42 | ; %1: Operand 1 |
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43 | ; %2: Operand 2 |
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44 | ; Returns: |
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45 | ; %1: Greater operand |
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46 | ; Corrupts registers: |
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47 | ; Nothing |
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48 | ;-------------------------------------------------------------------- |
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49 | %macro MAX_U 2 |
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50 | cmp %1, %2 ; Is %1 greater? |
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51 | ja %%Return ; If so, return |
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52 | mov %1, %2 ; Copy %2 to %1 |
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53 | ALIGN JUMP_ALIGN |
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54 | %%Return: |
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55 | %endmacro |
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56 | |
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57 | %macro MAX_S 2 |
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58 | cmp %1, %2 ; Is %1 greater? |
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59 | jg %%Return ; If so, return |
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60 | mov %1, %2 ; Copy %2 to %1 |
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61 | ALIGN JUMP_ALIGN |
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62 | %%Return: |
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63 | %endmacro |
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64 | |
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65 | |
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66 | ;-------------------------------------------------------------------- |
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67 | ; SHR_DXAX |
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68 | ; Parameters: |
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69 | ; %1: Number of bits to shift |
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70 | ; Returns: |
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71 | ; DX:AX Shifted value |
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72 | ; Corrupts registers: |
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73 | ; CX |
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74 | ;-------------------------------------------------------------------- |
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75 | %macro SHR_DXAX 1 |
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76 | %ifnidni %1, cx |
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77 | mov cx, %1 |
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78 | %endif |
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79 | ALIGN JUMP_ALIGN |
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80 | .ShiftNextBit: |
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81 | shr dx, 1 |
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82 | rcr ax, 1 |
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83 | loop .ShiftNextBit |
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84 | %endmacro |
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85 | |
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86 | |
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87 | %endif ; MATH_INC |
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