304:
In many cases, however, a directly equivalent instruction does not exist. The workaround might be obvious or it might not. For example, if saturation behavior is required on the SPU, it can be coded by adding additional SPU instructions to accomplish this (with some loss of efficiency). At the other
257:
to expose useful SPU instructions in C and C++. Instructions that differ only in the type of operand (such as a, ai, ah, ahi, fa, and dfa for addition) are typically represented by a single C/C++ intrinsic which selects the proper instruction based on the type of the operand.
35:
An open source software-based strategy was adopted to accelerate the development of a Cell BE ecosystem and to provide an environment to develop Cell applications, including a GCC-based Cell compiler, binutils and a port of the Linux operating system.
288:
In some cases it is possible to port existing VMX code directly. If the VMX code is highly generic (makes few assumptions about the execution environment) the translation can be relatively straightforward. The two processors specify a different
285:. Depending on how many VMX specific features are involved, the adaptation involved can range anywhere from straightforward, to onerous, to completely impractical. The most important workloads for the SPU generally map quite well.
244:
The IBM PPE Vector/SIMD manual does not define operations for double-precision floating point, though IBM has published material implying certain double-precision performance numbers associated with the Cell PPE VMX technology.
305:
extreme, if Java floating-point semantics are required, this is almost impossible to achieve on the SPU processor. To achieve the same computation on the SPU might require that an entirely different
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515:
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Transferring data between the local stores of different SPUs can have a large performance cost. The local stores of individual SPUs can be exploited using a variety of strategies.
89:(Vector Multimedia Extensions) technology is conceptually similar to the vector model provided by the SPU processors, but there are many significant differences.
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Applications with high locality, such as dense matrix computations, represent an ideal workload class for the local stores in Cell BE.
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exist with the same behaviors, they do not have the same instruction names, so this must be mapped as well. IBM provides compiler
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535:
412:
IBM Systems
Journal - Using advanced compiler technology to exploit the performance of the Cell Broadband Engine architecture
294:
787:
398:
364:
27:-compatible PPU core, and novel software development challenges with regard to the functionally reduced SPU coprocessors.
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that could potentially be adapted and recompiled to run on the SPU. This code base includes VMX code that runs under the
316:. For this reason, most algorithms adapted to Altivec will usually adapt successfully to the SPU architecture as well.
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573:
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464:"Using advanced compiler technology to exploit the performance of the Cell Broadband Engine architecture"
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561:
524:
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360:
Using advanced compiler technology to exploit the performance of the Cell
Broadband Engine architecture
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The most important conceptual similarity between VMX and the SPU architecture is supporting the same
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compliance where the Java standard falls silent. In a typical implementation, non-Java mode converts
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20:
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values to zero but Java mode traps into an emulator when the processor encounters such a value.
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More sophisticated applications can use multiple strategies for different data types.
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481:"Cell GC: Using the Cell Synergistic Processor as a Garbage Collection Coprocessor"
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which take care of this mapping transparently as part of the development toolkit.
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383:"An Open Source Environment for Cell Broadband Engine System Software"
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IBM Research
Project - Compiler Technology for Scalable Architectures
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There is a great body of code which has been developed for other
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involves a mixture of conventional development practices for the
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48:
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Streaming computations can be efficiently accommodated using
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of memory block transfers using a multi-buffering strategy.
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The software cache offers a solution for random accesses.
447:"Synergistic Processing in Cell's Multicore Architecture"
293:, so recompilation is required at a minimum. Even where
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377:
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432:IBM's Octopiler, or, why the PS3 is running late
365:Compiler Technology for Scalable Architectures
509:
8:
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355:Optimizing Compiler for a CELL Processor
91:
371:
7:
14:
350:The Cell Project at IBM Research
233:, extended to include IEEE and
81:Differences between VMX and SPU
670:Initiative for a Common Engine
562:Synergistic Processing Element
281:, where it is better known as
199:single precision, IEEE double
1:
624:Toshiba Qosmio F50, G50, G55
415:, 2017-10-23, archived from
762:Simultaneous multithreading
586:Vector Multimedia Extension
253:Compilers for Cell provide
227:Java Language Specification
814:
531:
435:, ArsTechnica, 2006-02-26
309:be written from scratch.
268:IBM Power microprocessors
721:STI Center of Competence
574:Power Processing Element
320:Local store exploitation
262:Porting VMX code for SPU
229:1 subset of the default
742:Heterogeneous computing
182:big (default), little
94:VMX to SPU Comparison
788:Cell BE architecture
685:Software development
525:Cell BE architecture
76:Adapting VMX for SPU
71:Software portability
17:Software development
332:software pipelining
314:vectorization model
168:saturation support
100:
57:software developers
21:Cell microprocessor
629:IBM BladeCenter QS
607:Sony PlayStation 3
291:binary code format
92:
775:
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752:Scratchpad memory
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149:128-bit quadword
805:
767:Vector processor
639:Namco System 357
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225:conforms to the
205:Memory alignment
146:128-bit quadword
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595:Implementations
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469:. January 2006.
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143:register width
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65:Cell processors
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711:James A. Kahle
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634:IBM Roadrunner
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212:quadword only
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196:Java, non-Java
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191:floating point
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179:byte ordering
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163:8, 16, 32, 64
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706:Peter Hofstee
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486:. March 2008.
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452:. March 2006.
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419:on 2006-04-11
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231:IEEE Standard
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209:quadword only
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31:Linux on Cell
30:
28:
26:
22:
18:
716:Ken Kutaragi
684:
665:Folding@home
555:Architecture
475:
458:
441:
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417:the original
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388:. June 2007.
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295:instructions
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219:
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97:
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84:
44:
43:
34:
16:
15:
701:David Bader
680:PhyreEngine
602:Fabrication
567:SpursEngine
274:version of
185:big endian
782:Categories
344:References
299:intrinsics
255:intrinsics
249:Intrinsics
129:number of
98:unfinished
51:prototype
798:Vaporware
793:Compilers
747:Power ISA
737:Gameframe
307:algorithm
160:8, 16, 32
131:registers
59:to write
55:to allow
45:Octopiler
40:Octopiler
653:Software
617:clusters
279:Mac OS X
239:denormal
218:The VMX
157:formats
124:32 bits
53:compiler
19:for the
675:OtherOS
541:Toshiba
283:Altivec
276:Apple's
272:PowerPC
155:integer
121:32 bits
104:feature
25:PowerPC
694:People
660:Apulet
612:models
193:modes
579:Xenon
484:(PDF)
467:(PDF)
450:(PDF)
386:(PDF)
118:size
49:IBM's
757:SIMD
730:Misc
644:Zego
536:Sony
223:mode
221:Java
138:128
116:word
110:SPU
85:The
63:for
61:code
546:IBM
235:C9X
174:no
171:yes
107:VMX
87:VMX
47:is
784::
374:^
135:32
67:.
517:e
510:t
503:v
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