Fixed-point load and store instructions

The fixed point load instructions move information from a location addressed by the effective address (EA) into one of the GPRs.

The fixed-point load instructions move information from a location addressed by the effective address (EA) into one of the GPRs. The load instructions compute the EA when moving data. If the storage access does not cause an alignment interrupt or a data storage interrupt, the byte, halfword, or word addressed by the EA is loaded into a target GPR.

The fixed-point store instructions perform the reverse function. If the storage access does not cause an alignment interrupt or a data storage interrupt, the contents of a source GPR are stored in the byte, halfword, or word in storage addressed by the EA.

In user programs, load and store instructions which access unaligned data locations (for example, an attempt to load a word which is not on a word boundary) will be executed, but may incur a performance penalty. Either the hardware performs the unaligned operation, or an alignment interrupt occurs and an operating system alignment interrupt handler is invoked to perform the unaligned operation.