ARM 指令 关于DCD和SPACE的一个问题

Golden_Chen 2009-04-16 01:18:21
语句如下:
FiqStackSpace SPACE FIQ_Stack_Legth
FiqStack DCD FiqStackSpace + FIQ_Stack_Legth

最后一条语句,DCD的后面跟FiqStackSpace + FIQ_Stack_Legth,
DCD后面的FiqStackSpace,表示一串空字符,这好理解
但是再上FIQ_Stack_Legth,就不明白了,WHY?
...全文
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gzp20 2009-11-17
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很有用啊
OneOnce 2009-11-13
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FiqStackSpace SPACE FIQ_Stack_Legth
FiqStack DCD FiqStackSpace + FIQ_Stack_Legth

分配一直空间,起始地址是:FIQ_Stack_Legth ,空间大小FiqStackSpace + FIQ_Stack_Legth(其实地址加偏移量或者说长度)。

就跟C中申请内存一样:
PBYTE p;
p = (PBYTE)malloc(100);
lzycome 2009-11-12
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ldr r0,=XX 此时的 XX 是地址(伪指令)
ldr r0,XX 此时的 XX 是值
Golden_Chen 2009-04-20
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{Label} DCD expr 表示分配一段字内存,并用expr初始化
上楼说FiqStackSpace+ FIQ_Stack_Legth 是一个地址值,那编译时如何区分地址值和初始化值的?
这一点比较迷糊。
liaifeilove 2009-04-16
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FiqStackSpace是标号,相当与地址,实际上就是在FiqStackSpace SPACE FIQ_Stack_Legth 这个语句给分配的空间的首地址,FiqStackSpace+ FIQ_Stack_Legth 是这个地址空间的结束地址,将FiqStack指向这个地址,当做栈的顶部,该栈向下生长,长度FIQ_Stack_Legth
前言...............................................................................................................................................................i 目录...............................................................................................................................................................I ARM7TDMI(-S)指令集及汇编....................................................................................................................1 ARM 处理器寻址方式..........................................................................................................................2 寄存器寻址...................................................................................................................................2 立即寻址.......................................................................................................................................2 寄存器偏移寻址............................................................................................................................2 寄存器间接寻址............................................................................................................................3 基址寻址.......................................................................................................................................3 多寄存器寻址...............................................................................................................................4 堆栈寻址.......................................................................................................................................4 块拷贝寻址...................................................................................................................................5 相对寻址.......................................................................................................................................5 指令集介绍...........................................................................................................................................7 ARM 指令集.................................................................................................................................7 指令格式...............................................................................................................................7 第2 个操作数................................................................................................................7 #immed_8r ...........................................................................................................7 Rm..........................................................................................................................8 Rm,shift..................................................................................................................8 条件码............................................................................................................................9 ARM 存储器访问指令........................................................................................................ 11   LDR 和STR ........................................................................................................ 11   LDM 和STM.......................................................................................................14   SWP .....................................................................................................................17 ARM 数据处理指令............................................................................................................19 数据传送指令..............................................................................................................20   MOV ............................................................................................................20   MVN ............................................................................................................20 算术逻辑运算指令......................................................................................................20   ADD.............................................................................................................20   SUB..............................................................................................................21   RSB..............................................................................................................21   ADC .............................................................................................................21   SBC..............................................................................................................21   RSC..............................................................................................................22   AND.............................................................................................................22   ORR..............................................................................................................22   EOR..............................................................................................................22 比较指令......................................................................................................................23   CMP.............................................................................................................23   CMN.............................................................................................................23   TST...............................................................................................................24   TEQ..............................................................................................................24 乘法指令......................................................................................................................25   MUL.............................................................................................................25   MLA.............................................................................................................25   UMULL........................................................................................................25   UMLAL........................................................................................................26   SMULL........................................................................................................26   SMLAL........................................................................................................26 ARM 跳转指令....................................................................................................................27   B...........................................................................................................................27   BL.........................................................................................................................27   BX........................................................................................................................27 ARM 协处理器指令............................................................................................................28   CDP......................................................................................................................28   LDC......................................................................................................................29   STC ......................................................................................................................29   MCR.....................................................................................................................30   MRC.....................................................................................................................30 ARM 杂项指令....................................................................................................................31   SWI ......................................................................................................................31   MRS.....................................................................................................................32   MSR.....................................................................................................................33 ARM指令........................................................................................................................34   ADR.....................................................................................................................35   ADRL...................................................................................................................35   LDR......................................................................................................................36   NOP......................................................................................................................37 Thumb 指令集.............................................................................................................................39 Thumb 指令集与ARM 指令集的区别..............................................................................39 Thumb 存储器访问指令.....................................................................................................40   LDR 和STR ........................................................................................................41   PUSH 和POP ......................................................................................................43   LDMIA 和STMIA ..............................................................................................43 Thumb 数据处理指令.........................................................................................................45 数据传送指令..............................................................................................................46   MOV ............................................................................................................46   MVN ............................................................................................................46   NEG..............................................................................................................47 算术逻辑运算指令......................................................................................................47   ADD.............................................................................................................47   SUB..............................................................................................................48   ADC .............................................................................................................49   SBC..............................................................................................................49   MUL.............................................................................................................50   AND.............................................................................................................50   ORR..............................................................................................................50   EOR..............................................................................................................51   BIC...............................................................................................................51   ASR..............................................................................................................51   LSL...............................................................................................................52   LSR ..............................................................................................................52   ROR..............................................................................................................53 比较指令......................................................................................................................53   CMP.............................................................................................................53   CMN.............................................................................................................54   TST...............................................................................................................54 Thumb 跳转指令.........................................................................................................55   B...................................................................................................................55   BL.................................................................................................................55   BX................................................................................................................55 Thumb 杂项指令.........................................................................................................56   SWI ..............................................................................................................56 Thumb 伪指令.............................................................................................................57   ADR .............................................................................................................57   LDR..............................................................................................................57   NOP..............................................................................................................58 伪指令.................................................................................................................................................59 符号定义伪指令..........................................................................................................................59   GBLA、GBLL、GBLS ..............................................................................................59   LCLA、LCLL、LCLS................................................................................................60   SETA、SETL、SETS .................................................................................................61   RLIST..........................................................................................................................61   CN...............................................................................................................................62   CP................................................................................................................................62   DN、SN.......................................................................................................................62   FN................................................................................................................................63 数据定义伪指令..........................................................................................................................63   LTORG.........................................................................................................................64   MAP............................................................................................................................64   FIELD ..........................................................................................................................65   SPACE..........................................................................................................................66   DCB .............................................................................................................................66   DCDDCDU............................................................................................................67   DCDO ..........................................................................................................................67 DCFD 和DCFDU........................................................................................................68   DCFS 和DCFSU.........................................................................................................68   DCI..............................................................................................................................69   DCQ 和DCQU............................................................................................................69   DCW 和DCWU..........................................................................................................70 报告伪指令.................................................................................................................................70   ASSERT.......................................................................................................................70   INFO ............................................................................................................................71   OPT.............................................................................................................................71   TTL 和SUBT ..............................................................................................................72 汇编控制伪指令..........................................................................................................................73   IF、ELSE 和ENDIF...................................................................................................73   MACRO 和MEND .....................................................................................................74   WHIL 和WEND .........................................................................................................75 杂项伪指令.................................................................................................................................76   ALIGN .........................................................................................................................77   AREA...........................................................................................................................78   CODE16 和CODE32..................................................................................................79   END .............................................................................................................................80   ENTRY.........................................................................................................................80   EQU .............................................................................................................................81   EXPORT 和GLOBAL ................................................................................................81   IMPORT 和EXTERN.................................................................................................82   GET 和INCLUDE ......................................................................................................83   INCBIN........................................................................................................................83   KEEP...........................................................................................................................83   NOFP ...........................................................................................................................84   REQUIRE ....................................................................................................................84   PEQUIRE8 和PRESERVE8 .......................................................................................84   RN...............................................................................................................................84   ROUT...........................................................................................................................85 ARM指令...............................................................................................................................86   ADR............................................................................................................................86   ADRL...........................................................................................................................86   LDR.............................................................................................................................86   NOP.............................................................................................................................86   LDFD...........................................................................................................................86   LDFS...........................................................................................................................87 Thumb 伪指令.............................................................................................................................87   ADR............................................................................................................................87   LDR.............................................................................................................................87   NOP.............................................................................................................................88 ARM 汇编程序设计............................................................................................................................88 文件格式.....................................................................................................................................88 ARM 汇编的一些规范................................................................................................................88 汇编语句格式......................................................................................................................88 标号.....................................................................................................................................89   基于PC 的标号...................................................................................................89   基于寄存器的标号..............................................................................................90   绝对地址..............................................................................................................90 局部标号..............................................................................................................................90 符号.....................................................................................................................................91 常量.....................................................................................................................................91   数字常数..............................................................................................................91   字符常量..............................................................................................................92   布尔常量..............................................................................................................92 段定义.................................................................................................................................92 宏定义及其作用..................................................................................................................93 子程序的调用..............................................................................................................................94 数据比较跳转..............................................................................................................................95 循环.............................................................................................................................................95 数据块复制.................................................................................................................................95 栈操作.........................................................................................................................................96 特殊寄存器定义及应用..............................................................................................................96 散转功能.....................................................................................................................................97 查表操作.....................................................................................................................................97 长跳转.........................................................................................................................................97 对信号量的支持..........................................................................................................................98 伪指令使用.................................................................................................................................98 一个完整的例子..........................................................................................................................98 外围部件控制..............................................................................................................................99 三级流水线介绍..........................................................................................................................99 C 与汇编混合编程............................................................................................................................100 内嵌汇编...................................................................................................................................100 内嵌汇编的指令用法........................................................................................................103 内嵌汇编器与armasm 汇编器的差异.............................................................................104 内嵌汇编注意事项............................................................................................................104 访问全局变量............................................................................................................................106 C 与汇编相互调用....................................................................................................................107 寄存器的使用规则............................................................................................................108 堆栈使用规则....................................................................................................................108 参数传递规则....................................................................................................................109 C 程序调用汇编程序........................................................................................................ 110 汇编程序调用C 程序....................................................................................................... 111 ARM 指令集列表.............................................................................................................................. 113 ARM 存储器访问指令表列表.................................................................................................. 113 ARM 数据处理指令列表.......................................................................................................... 114 ARM 乘法指令列表.................................................................................................................. 115 ARM 跳转指令列表.................................................................................................................. 116 ARM 协处理器指令列表.......................................................................................................... 117 ARM 杂项指令列表.................................................................................................................. 118 ARM指令列表...................................................................................................................... 119 Thumb 指令集列表...........................................................................................................................120 Thumb 存储器访问指令列表...................................................................................................120 Thumb 数据处理指令列表.......................................................................................................121 Thumb 跳转指令及软中断指令列表.......................................................................................122 Thumb 伪指令列表...................................................................................................................123 汇编预定义变量及伪指令................................................................................................................124 预定义的寄存器和协处理器名................................................................................................124 通用寄存器........................................................................................................................124 程序状态寄存器................................................................................................................124 浮点数寄存器....................................................................................................................124 协处理器及协处理器寄存器............................................................................................125 内置变量列表............................................................................................................................125 伪指令列表...............................................................................................................................126 指令条件码列表........................................................................................................................128 CPSR 和SPSR 分配图.............................................................................................................................129

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