Lhbrx - IBM PPC440X5 CPU Core User Manual

Preliminary

lhbrx

Load Halfword Byte-Reverse Indexed
lhbrx RT, RA, RB
31
0 6
EA (RA|0) + (RB)
16
(RT) 0 || BYTE_REVERSE(MS(EA,2))
An effective address (EA) is formed by adding an index to a base address. The index is the contents of
register RB. The base address is 0 if the RA field is 0 and is the contents of register RA otherwise.
The halfword at the EA is byte-reversed from the default byte ordering for the memory page referenced by the
EA. The resulting halfword is extended to 32 bits by concatenating 16 0-bits to its left. The result is placed into
register RT.
If instruction bit 31 contains 1, the contents of CR[CR0] are undefined.
Registers Altered
• RT
Invalid Instruction Forms
• Reserved fields
Programming Note
Byte ordering is generally controlled by the Endian (E) storage attribute (see Memory Management on
page 133). The load byte reverse instructions provide a mechanism for data to be loaded from a memory
page using the opposite byte ordering from that specified by the Endian storage attribute.
instrset.fm.
September 12, 2002
RT RA
11
Load Halfword Byte-Reverse Indexed
PPC440x5 CPU Core User's Manual
RB
16 21
lhbrx
790
31
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