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Page 457
Table 7.4 Some superscalar processors (based on a study by N. Ghazal).
(a) Chip Features of Processors
CharacteristicRS/6000SuperSparcDEC AlphaIntel PentiumMotorola/IBM Power PCH-P PA RISC 7100
Chip configuration3 (processing chips), 1 (mem control), and I (I/O control)Single chipSingle chipSingle chipSingle chipSingle chip
TechnologyCMOS, 1mmBiCMOS, .8mmCMOS, .75mm0.6mm BiCMOS0.6mm CMOS0.8mm CMOS
Die size161mm2, largest chip-233.5mm2163 mm2120 mm2202 mm2
No. of Transistors3.5M3.1M1.7M3.3M2.8M850K
Cycle Time3340 ns20 ns5 ns10 ns15 ns10 ns

(b) Processor Organization Features
FeatureRS/6000SuperSPARCDEC AlphaIntelMotorolaH-P
Prefetch I Buffer Size12-entry12-entry8-entry8-entry
Issue Rate (max per cycle)up to 4up to 32232
Instruction Window config.CentralCentralCentral (scoreboard)CentralCentralCentral
Data Dependency Resol.Interlocks (renaming for FP ops)InterlocksInterlocksInterlockingInterlocking (some renaming)Interlocking
Branch PolicyStaticDynamicStatic/dyn.DynamicStaticStatic
Branch TechniquePredict in-line (early CC set)default: Predict in-linedefault: Predict in-lineBTB with history bitsBackward branch predicted takenBackward branch predicted taken
Exception HandlingPrecisePreciseImprecise on arithmetic exc.

 
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