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Unformatted text preview: e-addressable memory
Some material is adapted from D. Culler & D. Patterson (UCB) S. Ziavras Addressing Modes
Specify how address of data object is to be derived Addressing modes affect
• Instruction counts
• Computer complexity
• Average CPI (clock cycles per instr.) Effective address (EA): address actually used to
Some material is adapted from D. Culler & D. Patterson (UCB) S. Ziavras Most Common Addressing Modes
Register Value in register Immediate Constant (part of instr.)
(part of instr.) Displacement Add displacement value to base address for EA Register indirect
indirect Reg. value is EA
value is EA Indexed Add index reg. to base reg. for EA Direct or absolute
or absolute Exact memory address in instr. is EA
memory address in instr is EA Memory indirect Memory location contains EA Autoincrement For stepping through arrays within a loop
stepping through arrays within loop Autodecrement
Scaled >> & R (R) - (decrement) Used to index arrays
to index arrays Some material is adap...
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This document was uploaded on 02/09/2014.
- Fall '09