
© G.N. Khan ARM Processors/Cores – EE8205: Embedded Computer Systems Page: 13
ARM7 Features
Combined Shift and ALU Execution Stage
• A single instruction can specify one of its two source operands for
shifting or rotation before it is passed to the ALU
• Allows very efficient bit manipulation and scaling code
• Eliminates virtually single shift instructions from ARM code.
ARM7 CPU does not have explicit shift instructions.
• A move instruction can apply a shift to its operand
ARM7 uses von-Neumann memory architecture where instructions
and data occupy single address space that can limit the performance
• Instruction fetching (and execution) must stop for instructions that
access memory
• The reduced cost of a single memory outweighs performance in
many embedded applications.
• The pipeline stalls during load and store operations, ARM7 can
continue useful work.
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