opcodeppc.txt

来自「这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统」· 文本 代码 · 共 78 行

PowerPC 32bits

reg = R0-R31
#imm = a value you set 

Bit expain 
0 = mean bit is zero
1 = mean bit is set
2 = mean this bit can be 0 or 1

opcode                                     Name 	  Desciptions							
0010 0000 0000 0000 1000 0000 0100 1110    blr		  return from a functions

0222 2222 2222 2222 2222 2222 0011 1000    Li   reg,#imm  move a value to a register

2222 2222 2222 2222 2222 2222 1001 0022    stw  reg,mem   store a value into memory 

2222 2222 2222 2222 2222 2222 1001 0122    stwu reg,mem   store contain of reg to memory and 
                                                          move reg to that memory position



Here how the primary opcode work 
xxxx xxxx xxxx xxxx DDDS SSSS 3333 33DD	  
   

3 = it is the primary opcode
D = Destions register
S = Source reigters   
                                                                        opcode
                                                           -------------------------
                                                           |bit order: 5432 10   67 |
     -------   -------                                      -----------         ----                                                                        
34: | 0c 00 | | e1 93 | stw r31,12(r1) 0000 1100 0000 0000 1110 0001 | 1001 00 | 00
38: | 14 00 | | 01 90 | stw r0,20(r1)  0001 0100 0000 0000 0000 0001 | 1001 00 | 11
     -------   -------                                                ---------  
        |         |
        |         |--> Get source register R0-R31 (0xE1 & 0x1F) = 1
        |         |
        |         |--> Get Dest register R0-R31 ((0xE1 & 0xE0)>>5) | ((0x90 & 0x3)<<3)  = 31 or 0      
        |         |     (The adding the two last bit on the end is maybe wrong need examine it)
        |         |
        |          --> Get the opcpde (0x90 & 0xFC)
       \ /        
                   
 The address offset 12 or 20
    
opcode                                 
 ---------------------------------------------------------
|bit order: pos   1111 1111 1111 1111 0000 0000 0000 0000 |
|	                                        5432 10   |
|---------------------------------------------------------|
|           bits  0000 1100 0000 0000 1110 0001 1001 0000 |
 ---------------------------------------------------------
| math    (opcode>>2) & 0x3F                              |
 ---------------------------------------------------------

Dest Register
 ---------------------------------------------------------
|bit order: pos   1111 1111 1111 1111 0000 0000 0000 0000 |
|                                     210              43 |
|---------------------------------------------------------|
|           bits  0000 1100 0000 0000 1110 0001 1001 0000 |
 ---------------------------------------------------------
| math (((opcode & 0x3) << 3) | ((opcode & 0xE000) >> 13))|
 ---------------------------------------------------------

source Register
 ---------------------------------------------------------
|bit order: pos   1111 1111 1111 1111 0000 0000 0000 0000 |
|                                        x xxxx           |
|---------------------------------------------------------|
|           bits  0000 1100 0000 0000 1110 0001 1001 0000 |
 ---------------------------------------------------------
| math                                                    |
 ---------------------------------------------------------