XCore Architecture: Difference between revisions

Revision as of 09:46, 2 July 2014

Revision as of 09:59, 2 July 2014

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This scheme is designed in order to densely encode the common cases found in many programming patterns: access to small stack frames, a small set of globals and constants, structures, and arrays. Access to bit fields that have an odd length is facilitated by means of sign and zero extend instructions.

All common arithmetic instructions are provided - including a divide and remainder (which are the only instructions that are not single cycle). Comparison instructions compute a [[truth value]] (0 or 1) into a register, avoiding the use of flags. Many instructions have an immediate version that allowallows a single operand with a value of between 0 and 11 inclusive, encoding many common cases such as "i = i + 1". In the case of bit operations such as shift, the immediate value encodes common cases. Extra instructions are provided for reversing bits and bytes, count leading zeros, [[digital signal processing]], and long integer arithmetic.

The branch instructions include conditional and unconditional relative