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Dealer Instruction Processing Unit Governor - Weaving Threads from Loop Unrolling

IP.com Disclosure Number: IPCOM000104979D
Original Publication Date: 1993-Jun-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 4 page(s) / 166K

Publishing Venue

IBM

Related People

Ekanadham, K: AUTHOR [+3]

Abstract

MSIS is a uniprocessor organization in which a set of processing elements (PEs) working in concert execute Segments of the instruction stream. The Segments are either P-Segments,normal uniprocessor instruction stream portions, that are processed in the E-MODE of MSIS and produce Z-Segments,or the Z-Segments that are processed in Z-MODE by MSIS. he main difference between E-MODE and Z-MODE is that during E-Mode each PE sees all instructions in the Segment an executes the ones that are assigned to it, but during Z-MODE a PE only sees the instructions assigned to it.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 34% of the total text.

Dealer Instruction Processing Unit Governor - Weaving Threads from Loop Unrolling

      MSIS  is  a uniprocessor  organization  in  which  a set of
processing elements (PEs) working in concert execute Segments of  the
instruction  stream.  The   Segments   are   either P-Segments,normal
uniprocessor instruction stream portions, that  are  processed  in
the  E-MODE  of  MSIS  and produce Z-Segments,or the Z-Segments that
are processed  in  Z-MODE by  MSIS.  he  main difference between
E-MODE and Z-MODE is that during E-Mode each PE  sees  all
instructions  in  the Segment  an  executes the ones that are
assigned to it, but during Z-MODE a PE only sees the  instructions
assigned  to it.

      As  all  PEs see  all  instructions  in E-MODE, each PE can
create the -CODE it will require to re-execute the  Segment as  a
Z-Segment, the Z-CODE being stored in the Z-CACHE, and associated
with instructions in the Z-CODE are  S-LISTS  and D-LISTS, as
appropriate.  An S-LIST instructs the PE, in the Z-MODE, that one or
more  of  the  source  registers  in  an instruction assigned  to  it
is set by another instruction that is executed on another PE; an
S-LIST  is  a  receiving obligation.  The D-LIST instructs the PE in
the Z-MODE as to the names o PEs that require the values of the
register(s) that are being set by an instruction that is assigned to
it.  A D-LIST entry is a sending obligation.

      The  set  of instructions  assigned  to a single PE can be
further delineated as THREADS.  A THREAD  is  a  sequence  of
instructions in the original conceptual order, and a Thread is
associated with  a  register  file  which is either real or virtual.
There  are  no  sending  or  receiving  obligations between
instructions  within a THREAD and the THREAD is the smallest unit of
aggregation of instructions from a SEGMENT.  Individual instructions
while executing carry an  indication as  to  which  SEGMENT,
DECODER,  and  THREAD they belong.  The information concerning the
DECODER  and  THREAD is  derived from  the  Z-CODE  itself.  The
SEGMENT index is assigned  sequentially  at  each  SEGMENT  SWITCH.
Segment switches  occur  at  points  in the code where the Z-SEGMENT
terminates or where a Branch Wrong Guess has been  detected.

      MSIS  HEM is  a  High End Machine design that uses multiple
decoders within a single processor in the place of  separate
processor  elements  (PEs).  A single Instruction Processing Unit
(IPU) executes all  instructions  in  MSIS  HEM  albeit through   a
multiplicity   of  register  files  that  are associated with the
THREADS.  MSIS META HEM  is  a  Multiple Execution  Thread
Architecture  that  separates the THREADS from the net higher
aggregate of instructions, the  DECODER.  Thus  the  action of S-LIST
and/or D-LIST entries within the Z-CODE activates and deactivates the
T...