as: s390 Register
9.40.3.1 Register naming
........................
The 'as' recognizes a number of predefined symbols for the various
processor registers. A register specification in one of the instruction
formats is an unsigned integer between 0 and 15. The specific
instruction and the position of the register in the instruction format
denotes the type of the register. The register symbols are prefixed
with '%':
%rN the 16 general purpose registers, 0 <= N <= 15
%fN the 16 floating point registers, 0 <= N <= 15
%aN the 16 access registers, 0 <= N <= 15
%cN the 16 control registers, 0 <= N <= 15
%lit an alias for the general purpose register %r13
%sp an alias for the general purpose register %r15
Info Catalog
as: s390 Syntax
as: s390 Mnemonics