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88-716: The InfiniteReality was introduced in early 1996 and was used in the Silicon Graphics Onyx . It succeeded the RealityEngine , although the RealityEngine coexisted with the InfiniteReality for some time for the Onyx as an entry-level option for deskside "workstation" configurations. The InfiniteReality architecture was a third-generation design and is categorized as a sort-middle architecture. It

176-431: A 0.7 μm process, which could be seen when looking at the chip from arm's length. Two popular approaches to dividing registers into multiple register files are the distributed register file configuration and the partitioned register file configuration. In principle, any operation that could be done with a 64-bit-wide register file with many read and write ports could be done with a single 8-bit-wide register file with

264-468: A 195-bit microinstruction, which is compressed in order to reduce size and bandwidth usage in return for slightly less performance. The Geometry Engine processor operates at 90 MHz, achieving a maximum theoretical performance of 540 MFLOPS. As there are four such processors on a GE12-4 or GE14-4 board, the maximum theoretical performance is 2.16 GFLOPS. A 16-pipeline system therefore achieves a maximum theoretical performance of 34.56 GFLOPS. The fourth stage

352-641: A 3.3 V power supply. An InfiniteReality pipeline in a maximal configuration contains 251 million transistors. The InfiniteReality was developed by 55 engineers. Given a system capable enough, such as certain models of the Onyx2 and Onyx 3000, up to 16 InfiniteReality pipelines can be hosted. The pipelines can be operated in three modes: multi-seat, multi-display and multi-pipe. In multi-seat mode, each pipeline can serve up to eight simultaneous users, each with their own separate displays, keyboards and mice. In multi-display mode, multiple outputs drive multiple displays, which

440-494: A 32-bit by 32-entry register file with two read and two write ports. These cores are provided with a 32-bit by 2,560-entry memory that holds elements of OpenGL state and provides scratchpad storage. Each core also has a float-to-fix converter to convert floating-point values into integer form. The Geometry Engine is capable of completing three instructions per cycle, and each Geometry board, with four such devices, can complete 12 instructions per cycle. The Geometry Engine uses

528-541: A DG2 (Display Generator) board. The rack model differs by supporting up to three RealityEngine2 pipes (display outputs) vs the single pipe of the deskside. The VTX graphics subsystem is a cost reduced version of the RealityEngine2, using the same hardware but in a feature reduced configuration that can not be upgraded. It consists of one GE10 board (6 Intel i860XP processors vs 12 in RE2), a single RM4 or RM5 board, and

616-520: A DG2 board. InfiniteReality succeeded RealityEngine2 as the high-end graphics subsystem for the Onyx when introduced in 1996. As with RealityEngine2, two versions correspond to the form factors of the Onyx. The deskside version consists of a GE12 board, one or two RM6 boards (limited due to the amount of cooling the deskside system provides), and a DG4 board. The rack model increases the number of RM6 boards supported to four per pipe and allows up to three pipes to be installed resulting in an Onyx rack with

704-446: A Vdd and Vss. Therefore, the wire pitch area increases as the square of the number of ports, and the transistor area increases linearly. At some point, it may be smaller and/or faster to have multiple redundant register files, with smaller numbers of read ports, rather than a single register file with all the read ports. The MIPS R8000 's integer unit, for example, had a 9 read 4 write port 32 entry 64-bit register file implemented in

792-531: A bandwidth of 15.36 GB/s, and the raster memory has a bandwidth of 72.8 GB/s. The DG4-2 Display Generator board contains hardware to drive up to two video outputs, which may be expanded to eight video outputs with an optional daughterboard, a configuration known as the DG4-8 . The outputs are independent and each output has hardware for generating video timing, video resizing, gamma correction , genlock and digital-to-analog conversion . Digital-to-analog conversion

880-435: A datapath. Area can sometimes be saved on machines with multiple units in a datapath by having two datapaths side-by-side, each of which has smaller bit pitch than a single datapath would have. This case usually forces multiple copies of a register file, one for each datapath. The Alpha 21264 (EV6), for instance, was the first large micro-architecture to implement a "Shadow Register File Architecture". It had two copies of

968-463: A large area. The register window slides by 16 registers when moved, so that each architectural register name can refer to only a small number of registers in the larger array, e.g. architectural register r20 can only refer to physical registers #20, #36, #52, #68, #84, #100, #116, if there are just seven windows in the physical file. To save area, some SPARC implementations implement a 32-entry register file, in which each cell has seven "bits". Only one

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1056-407: A maximum of three GE12 boards, three DG4 boards, and twelve RM6 boards. An Onyx system with RealityEngine2 graphics was used by CBS News for a broadcast of real-time election results. The broadcast had 3D graphics that were generated live that had updated news feeds in real time. This required the video to be composited live in 3D for the viewers, which was done using an Onyx system. This is one of

1144-520: A register file in their internal design, Geode GX and Vortex86 and many embedded processors that aren't Pentium -compatible or reverse-engineered early 80x86 processors. Therefore, most of them don't have a register file for their decoders, but their GPRs are used individually. Pentium 4 (based on the NetBurst microarchitecture), on the other hand, does not have a register file for its decoder, as its x86 GPRs didn't exist within its structure, due to

1232-433: A register file like Intel and do not support "Shadow Register File Architecture" as its lack of context switch and bypass inverter that are necessary require for a register file to function appropriately. Instead they use a separate GPRs that directly link to a rename register table for its OoOE CPU with a dedicated integer decoder and floating decoder. The mechanism is similar to Intel's pre-Pentium processor line. For example,

1320-577: A simple array is read out vertically. That is, a single word line, which runs horizontally, causes a row of bit cells to put their data on bit lines, which run vertically. Sense amps , which convert low-swing read bitlines into full-swing logic levels, are usually at the bottom (by convention). Larger register files are then sometimes constructed by tiling mirrored and rotated simple arrays. Register files have one word line per entry per port, one bit line per bit of width per read port, and two bit lines per bit of width per write port. Each bit cell also has

1408-472: A single read port and a single write port. However, the bit-level parallelism of wide register files with many ports allows them to run much faster and thus, they can do operations in a single cycle that would take many cycles with fewer ports or a narrower bit width or both. The width in bits of the register file is usually the number of bits in the processor word size . Occasionally it is slightly wider in order to attach "extra" bits to each register, such as

1496-411: A small number of ports are often dominated by transistor area, it is best not to push this technique to this limit, but it is useful all the same. The SPARC ISA defines register windows , in which the 5-bit architectural names of the registers actually point into a window on a much larger register file, with hundreds of entries. Implementing multiported register files with hundreds of entries requires

1584-439: A subset of the physical register file. This arrangement can eliminate the need for multiple write ports per bit cell, for large savings in area. The resulting register file, effectively a stack of register files with single write ports, then benefits from replication and subsetting the read ports. At the limit, this technique would place a stack of 1-write, 2-read regfiles at the inputs to each functional unit. Since regfiles with

1672-715: Is Bonnell do not have a unified register file and has no dedicated register file for its hyper threading. Instead, Bonnell uses a separate rename register for its thread despite it is not out of order. Similar to Bonnell, Larrabee and Xeon Phi also each have only one general-purpose integer register file, but the Larrabee has up to 16 XMM register files (8 entries per file), and the Xeon Phi has up to 128 AVX-512 register files, each containing 32 512-bit ZMM registers for vector instruction storage, which can be as big as L2 cache. There are some other of Intel's x86 lines that don't have

1760-510: Is actually a part of the Video Bus, which has a bandwidth of 1.2 GB/s. Four Image Engine "cores" are contained on an Image Engine ASIC, which contains nearly 488,000 logic gates, comprising 1.95 million transistors, on a 42 mm (6.5 by 6.5 mm) die that was fabricated in a 0.35 micrometre process by VLSI Technology . The InfiniteReality uses the RM6-16 or RM6-64 Raster Managers. Each pipeline

1848-420: Is available. The InfiniteReality was capable of several advanced capabilities: The InfiniteReality's performance was: InfiniteReality2 is how hinv (an IRIX utility that lists the hardware present in a system) refers to an InfiniteReality that is used in the Onyx2. The InfiniteReality2 however, was still marketed as the InfiniteReality. It was the second implementation of the InfiniteReality architecture, and

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1936-644: Is based on the SGI Challenge servers, but with graphics hardware. The Onyx was employed in early 1995 for development kits used to produce software for the Nintendo 64 and, because the technology was so new, the Onyx was noted as the major factor for the impressively high price of US$ 100,000 – US$ 250,000 for such kits. The Onyx was succeeded by the Onyx2 in 1996 and was discontinued on March 31, 1999. The deskside variant can accept one CPU board, and

2024-569: Is big and complex compared to ARM). Because most x86's front-ends have become much larger and much more power hungry than the ARM processor in order to be competitive (example: Pentium M & Core 2 Duo, Bay Trail). Some third-party x86 equivalent processors even became noncompetitive with ARM due to having no dedicated register-file architecture. Particularly for AMD, Cyrix and VIA that cannot bring any reasonable performance without register renaming and out of order execution, which leave only Intel Atom to be

2112-400: Is capable of display resolutions of 2.62, 5.24 or 10.48 million pixels, provided that one, two or four Raster Manager boards respectively are present. The raster memory can be configured to use 256, 512 or 1024 bits per pixel. 320 MB supports a resolution of 2560 by 2048 pixels with each pixel containing 512 bits of information. In a configuration with four Raster Managers, the texture memory has

2200-432: Is common to have bypass multiplexers that bypass written data to the read ports when a simultaneous read and write to the same entry is commanded. These bypass multiplexers are often part of a larger bypass network that forwards results which have not yet been committed between functional units. The register file is usually pitch-matched to the datapath that it serves. Pitch matching avoids having many busses passing over

2288-406: Is more than one, before the instruction is issued, but this only exists on processors that support superscalar execution. However, context switching is a totally different mechanism to ARM's register bank within the registers. The MODCOMP and the later 8051-compatible processors use bits in the program status word to select the currently active register bank. The usual layout convention is that

2376-673: Is not including floating point/SSE functions. In later x86 implementations, like Nehalem and later processors, both integer and floating point registers are now incorporated into a unified octa-ported (six read and two write) general-purpose register file (8 + 8 in 32-bit and 16 + 16 in x64 per file), while the register file extended to 2 with enhanced "Shadow Register File Architecture" in favorite of executing hyper threading and each thread uses independent register files for its decoder. Later Sandy bridge and onward replaced shadow register table and architectural registers with much large and yet more advance physical register file before decoding to

2464-739: Is part of the architecture and visible to the programmer, as opposed to the concept of transparent caches . In simpler CPUs, these architectural registers correspond one-for-one to the entries in a physical register file (PRF) within the CPU. More complicated CPUs use register renaming , so that the mapping of which physical entry stores a particular architectural register changes dynamically during execution. Modern integrated circuit -based register files are usually implemented by way of fast static RAMs with multiple ports. Such RAMs are distinguished by having dedicated read and write ports, whereas ordinary multiported SRAMs will usually read and write through

2552-410: Is performing geometry and image processing. The Geometry Engine is used for the purpose, with each Geometry board containing up to four working in a multiple instruction multiple data (MIMD) fashion. The Geometry Engine is a semi-custom ASIC with a single instruction multiple data (SIMD) pipeline containing three floating-point cores, each containing an arithmetic logic unit (ALU), a multiplier and

2640-457: Is plugged into the rear of a midplane, which can support two pipelines. The midplane has eleven slots. Slot six to slot eleven are for the first pipeline, which may contain one to four Raster Manager boards. Slot one to four is for the second pipeline, which may contain one or two Raster Manager boards due to the number of slots there are. Because of this, maximally configured Onyx systems use one midplane for each pipeline to avoid restricting half of

2728-409: Is provided by 8-bit digital-to-analog converters that support a pixel clock frequency up to 220 MHz. Data for the video outputs are provided by four ASICs that de-serialize and de-interleave the 160-bit streams into 10-bit component RGBA , 12-bit component RBGA, L16, Stereo Field Sequential (FS) or color indexes. The hardware also incorporates the cursor at this stage. A 32,768 entry color index map

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2816-482: Is read and writeable through the external ports, but the contents of the bits can be rotated. A rotation accomplishes in a single cycle a movement of the register window. Because most of the wires accomplishing the state movement are local, tremendous bandwidth is possible with little power. This same technique is used in the R10000 register renaming mapping file, which stores a 6-bit virtual register number for each of

2904-462: Is served as a scaled shadow register file, which without context switch the scaled file cannot store some instruction independently. Some instruction from SSE2/SSE3/SSSE3 require this feature for integer operation, for example instruction like PSHUFB, PMADDUBSW, PHSUBW, PHSUBD, PHSUBSW, PHADDW, PHADDD, PHADDSW would require loading EAX/EBX/ECX/EDX from both register files, though it was uncommon for an x86 processor to make use of another register file with

2992-400: Is small enough to be able to fit in one register and its architectural register act as a table and shared with all decoder/instructions with simple bank switching between decoders. The major difference between ARM and other designs is that ARM allows to run on the same general-purpose register with quick bank switching without requiring additional register file in superscalar. Despite x86 sharing

3080-538: Is the Geometry-Raster FIFO , a first in first out (FIFO) buffer that merges the outputs of the four Geometry Engines into one, reassembling the outputs in the order they were issued. The FIFO is built from SDRAM and has a capacity of 4 MB, large enough to store 65,536 vertexes . The transformed vertexes are moved from this FIFO to the Raster Manager boards for triangle reassembly and setup by

3168-714: Is used to connect the Host Interface Processor ASIC on the Geometry Board to the Ibus on the IO4 board, a part of the host system. The Geometry board is responsible for geometry and image processing and is divided into four stages, each stage being implemented by separate device(s). The first stage is the Host Interface . Due to the InfiniteReality being designed for two very different platforms,

3256-615: Is used to fetch display list objects using direct memory access (DMA). The Host Interface Processor is accompanied by 16 MB of synchronous dynamic random access memory (SDRAM), of which 15 MB is used to cache display leaf objects. The cache can deliver data to the next stage at over 300 MB/s. The next stage is the Geometry Distributor , which transfers data and instructions from the Host Interface Processor to individual Geometry Engines. The next stage

3344-429: Is useful for virtual reality . The multi-pipe mode has two methods of operation. The first method requires a digital multiplexer (DPLEX) daughterboard to be installed in every pipeline, which combines the output of multiple pipelines. The second method uses MonsterMode software to distribute the data used to render a frame to multiple pipelines. To interface the pipeline to the system, a Flat Cable Interface (FCI) cable

3432-619: The K6 processor has four int (one eight-entries temporary scratched register file + one eight-entries future register file + one eight-entries fetched register file + an eight-entries unnamed register file) and two FP rename register files (two eight-entries x87 ST file one goes fadd and one goes fmov) that directly link with its x86 EAX for integer renaming and XMM0 register for floating point renaming, but later Athlon included "shadow register" in its front end, it's scaled up to 40 entries unified register file for in order integer operation before decoded,

3520-681: The Raster Manager ) and Display Generator boards, with each board corresponding to each stage of the three major stages in the architecture's pipeline. The board set partitioning scheme is the same as the RealityEngine, as a result of Silicon Graphics wanting the RealityEngine to be easily upgradable to the InfiniteReality. Each pipeline consists of one Geometry Engine board, one, two or four Raster Manager boards and one Display Generator board. The implementation comprises twelve ASIC designs fabricated in 0.5 and 0.35 micrometre processes with three layers of metal interconnect. These ASICs require

3608-862: The Scan Converter (SC) ASIC, the Texel Address Calculator (TA) ASIC, the Texture Memory Controller (TM) ASIC and the Texture Fragment (TF) ASIC. The SC ASIC and the TA ASIC perform scan conversion, color and depth interpolation, perspective correct texture coordinate interpolation and level of detail computation on incoming data, and the results are passed to the eight TM ASICs, which are specialized memory controllers optimized for texel access. Each TM ASIC controls four SDRAMs that make up one-eighth of

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3696-483: The 16 pipelines to a maximum of two Raster Manager boards. Slot five contains a Ktown board if the midplane is used in an Origin 2000-based system (Onyx2) or a Ktown2 board if the midplane is used in an Origin 3000-based system (Onyx 3000). The purpose of these boards is to interface the host system's XIO link to the Host Interface Processor ASIC on the Geometry board. These boards have two XIO ports for this purpose, with

3784-519: The IP25 board with one, two, or four R10000 CPUs at 195 MHz. The Onyx was launched with the RealityEngine2 or VTX graphics subsystems, and InfiniteReality was introduced in 1995. The RealityEngine2 is the original high-end graphics subsystem for the Onyx and was found in two different versions: deskside and rack. The deskside model has one GE10 (Geometry Engine) board with 12 Intel i860XP processors, up to four RM4 or RM5 (Raster Manager) boards, and

3872-594: The Image Engines perform anti-aliasing and accumulation buffer operations. To deliver pixel data for display, each Image Engine has a 2-bit serial bus to the Display Generator board. If one Raster Manager board is present in the pipeline, the Image Engine uses the entire width of the bus, whereas if two or more Raster Manager boards are present, the Image Engine uses half the bus. Each serial bus

3960-1027: The InfiniteReality2, introduced in 1998. It succeeded the InfiniteReality board set and was itself succeeded by the InfiniteReality3 in 2000, but was not discontinued until 10 April 2001. It improves upon the InfiniteReality by replacing the GE14-4 Geometry Engine board with the GE16-4 Geometry Engine board and the RM7-16 or RM7-64 Raster Manager boards with the RM9-64 Raster Manager board. The new Geometry Engine board operated at 112 MHz, improving geometry and image processing performance. The new Raster Manager board operated at 72 MHz, improving anti-aliased pixel fill performance. InfiniteReality3

4048-516: The InfiniteReality3 pipeline provides 320 MB of raster memory. InfiniteReality4 was introduced in 2002 to succeed the InfiniteReality3. It was used in the Onyx2, Onyx 3000 and Onyx 350. It is the last member of the InfiniteReality family, itself succeeded by the ATI FireGL -based UltimateVision, which was used in the Onyx4. The only improvement over the previous implementation was the replacement of

4136-710: The RM10-256 Raster Manager by the RM11-1024 Raster Manager, which has improved performance, 1 GB of texture memory and 2.5 GB of raster memory, four and thirty-two times that of the previous raster manager, respectively. When maximally configured with four Raster Managers, the InfiniteReality4 pipeline has 10 GB of raster memory. In a maximum configuration with 16 pipelines, the InfiniteReality4 contained 16 GB of texture memory and 160 GB of raster memory. The figures presented in

4224-657: The Triangle Bus (also known as the Vertex Bus), which has a bandwidth of 400 MB/s. The function of the Raster Memory board is to perform rasterization . It also contains the texture memory and raster memory , which is more commonly known as the framebuffer . Rasterization is performed in the Fragment Generator and the eighty Image Engines . The Fragment Generator comprises four ASIC designs:

4312-475: The appropriate TF ASIC, where texture filtering, texture environment combination with interpolated color and fog application is performed. As each SDRAM holds part of the texture memory, all of the 32 SDRAMs must be connected to all of the 80 Image Engines. To achieve this, the TM and TF ASICs implement a two-rank omega network , which reduces the number of individual paths required for the 32 to 80 sort while maintaining

4400-460: The architectural register files are external and located in the processor's backend after the retired file, as opposed to the internal register file located in the inner core for register renaming/reorder buffer. However, in Core 2 it is now housed within a unit called the "register alias table" (RAT), located with instruction allocator but have same size of register size as retirement. Core 2 increased

4488-492: The data, register files like architectural and floating point are located between code buffer and decoders, called "retire buffer", Reorder buffer and OoOE and connected within the ring bus (16 bytes). The register file itself still remains one x86 register file and one x87 stack and both serve as retirement storing. Its x86 register file was enlarged to dual-ported to increase bandwidth for result storage. Registers like debug/condition code/control/unnamed/flag were stripped from

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4576-401: The datapath turn corners, which would use a lot of area. But since every unit must have the same bit pitch, every unit in the datapath ends up with the bit pitch forced by the widest unit, which can waste area in the other units. Register files, because they have two wires per bit per write port, and because all the bit lines must contact the silicon at every bit cell, can often set the pitch of

4664-402: The first examples of a real-time 3D video compositing system used in a television broadcast. Register file A register file is an array of processor registers in a central processing unit (CPU). The instruction set architecture of a CPU will almost always define a set of registers which are used to stage data between memory and the functional units on the chip. The register file

4752-405: The floating point register file. However, unlike Alpha and x86, they are located in the backend as a retire unit right after the out-of-order unit and the renaming of register files. The shadow registers do not load instructions during instruction fetching and decoding stages and a context switch is unnecessary in this design. IBM uses the same mechanism as many major microprocessors, deeply merging

4840-410: The impact of the limited number of general-purpose registers in superscalar architectures with speculative execution. This design was later adapted by SPARC , MIPS and some of the later x86 implementations. The MIPS uses multiple register files as well. The R8000 floating-point unit had two copies of the floating-point register file, each with four write and four read ports, and wrote both copies at

4928-830: The inner ring bus to 24 bytes (allow more than 3 instructions to be decoded) and extended its register file from dual-ported (one read/one write) to quad-ported (two read/two write), register still remain 8 entries in 32 bit and 32 bytes (not including 6 segment register and one instruction pointer as they are unable to be access in the file by any code/instruction) in total file size and expanded to 16 entries in x64 for total 128 bytes size per file. From Pentium M as its pipeline port and decoder increased, but they're located with allocator table instead of code buffer. Its FP XMM register file are also increase to quad-ported (2 read/2 write), register still remain 8 entries in 32 bit and extended to 16 entries in x64 mode and number still remain 1 as its shadow-register-file architecture

5016-407: The integer register file and two copies of the floating point register located in its front end (future and scaled file, each containing 2 read and 2 write ports), and took an extra cycle to propagate data between the two during a context switch. The issuing logic attempted to reduce the number of operations forwarding data between the two and greatly improved its integer performance, and helped reduce

5104-524: The introduction of a physical unified renaming register file (similar to Sandy Bridge, but slightly different due to the inability of Pentium 4 to use the register before naming) for attempting to replace the architectural register file and skip the x86 decoding scheme. Instead it uses SSE for integer execution and storage before the ALU and after result, SSE2/SSE3/SSSE3 use the same mechanism as well for its integer operation. AMD 's early design like K6 do not have

5192-757: The lack of a context switch. In the x86 processor line, a typical pre-486 CPU did not have an individual register file, as all general purpose registers worked directly with the decoder, and the x87 push stack was located within the floating-point unit itself. Starting with the Pentium , a typical Pentium-compatible x86 processor is integrated with one copy of a single-port architectural register file containing 6 general-purpose registers, 4 control registers, 8 debug registers (two reserved), 1 stack pointer register, 1 stack base register, 1 instruction pointer, 1 flags register, and 6 segment registers. Processors did not have dedicated registers for MMX , and so Intel instead used

5280-405: The main register file and placed into individual files between the micro-op ROM and instruction sequencer. Only inaccessible registers like the segment register are now separated from the general-purpose register file (except the instruction pointer); they are now located between the scheduler and instruction allocator, in order to facilitate register renaming and out-of-order execution. The x87 stack

5368-429: The only in-order x86 processor core in the mobile competition. This was until the x86 Nehalem processor merged both of its integer and floating point register into one single file, and the introduction of a large physical register table and enhanced allocator table in its front-end before renaming in its out-of-order internal core. Processors that perform register renaming can arrange for each functional unit to write to

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5456-540: The original P5 design and located after the execution unit, and the file of these registers is single-ported and not expose to instruction like scaled shadow register file found on Core/Core2 (shadow register file are made of architectural registers and Bonnell did not due to not have "Shadow Register File Architecture"), however the file can be use for renaming purpose due to lack of out of order execution found on Bonnell architecture. It also had one copy of XMM floating point register file per thread. The difference from Nehalem

5544-455: The other models. The RM8-16 and RM864 has 16 or 64 MB of texture memory respectively and 40 MB of raster memory. The Reality was also limited by the number of Raster Manager boards it could support, one or two. When maximally configured with two RM8-64 Raster Manager boards, the Reality pipeline has 80 MB of raster memory. The InfiniteReality2E was an upgrade of the InfiniteReality, marketed as

5632-443: The physical register which the banked registers, R8 to R14, point to depends on the operating mode the processor is in. Notably, Fast Interrupt Request (FIQ) mode has its own bank of registers for R8 to R12, with the architecture also providing a private stack pointer (R13) for every interrupt mode. x86 processors use context switching and fast interrupts for switching between instruction, decoder, GPRs and register files, if there

5720-406: The poison bit. If the width of the data word is different than the width of an address—or in some cases, such as the 68000 , even when they are the same width—the address registers are in a separate register file than the data registers. The basic scheme for a bit cell: Many optimizations are possible: Most register files make no special provisions to prevent multiple write ports from writing to

5808-531: The rackmount variant can take up to six CPU boards. Both models were launched with the IP19 CPU board with one, two, or four MIPS R4400 CPUs, initially with 100 and 150 MHz options and later increased to 200 and 250 MHz. Later, the IP21 CPU board was introduced, with one or two R8000 microprocessors at 75 or 90 MHz; machines with this board were referred to as POWER Onyx. Finally, SGI introduced

5896-504: The register file contain 8 entries scratch register + 16 future GPRs register file + 16 unnamed GPRs register file. In later AMD designs it abandons the shadow register design and favored to K6 architecture with individual GPRs direct link design. Like Phenom , it has three int register files and two SSE register files that are located in the physical register file directly linked with GPRs. However, it scales down to one integer + one floating-point on Bulldozer . Like early AMD designs, most of

5984-557: The register file with the decoder, but its register files work independently of the decoder side and do not involve context switching, which is different from Alpha and x86. Most of its register files do not only serve its dedicated decoder, but also serve up to the thread level. For example, POWER8 has up to 8 instruction decoders, but up to 32 register files of 32 general purpose registers each (4 read and 4 write ports) to facilitate simultaneous multithreading , as its parallel instructions cannot be used across any other register file due to

6072-652: The reorder buffer. Randered that Sandy Bridge and onward no longer carry an architectural register. On the Atom line was the modern simplified revision of P5. It includes single copies of register file share with thread and decoder. The register file is a dual-port design, 8/16 entries GPRS, 8/16 entries debug register and 8/16 entries condition code are integrated in the same file. However it has an eight-entries 64 bit shadow based register and an eight-entries 64 bit unnamed register that are now separated from main GPRs unlike

6160-433: The same entry simultaneously. Instead, the instruction scheduling hardware ensures that only one instruction in any particular cycle writes a particular entry. If multiple instructions targeting the same register are issued, all but one have their write enables turned off. The crossed inverters take some finite time to settle after a write operation, during which a read operation will either take longer or return garbage. It

6248-499: The same functionality. The eighty Image Engines have multiple functions. Firstly, each Image Engine controls a portion of the raster memory, which in the case of the InfiniteReality, is a 1 MB SGRAM organized as 262,144 by 32-bit words. Secondly, the following OpenGL per-fragment operations are performed by the Image Engines: pixel ownership test, stencil test, depth buffer test, blending, dithering and logical operation. Lastly,

6336-449: The same instruction. Most of time, the second file is served as a scale retired file. The Pentium M architecture still has one dual-ported floating-point register file (8 entries MM/XMM) shared with three decoders, and the FP register file does not have a shadow register file along with it, as its shadow-register-file architecture did not including floating-point functions. In processors after P6,

6424-424: The same mechanism with ARM that its GPRs can store any data individually, x86 will confront data dependency if more than three non-related instructions are stored, as its GPRs per file are too small (eight in 32 bit mode and 16 in 64 bit, compared to ARM's 13 in 32 bit and 31 in 64 bit) for data, and it is impossible to have superscalar without multiple register files to feed to its decoder (x86 code

6512-435: The same ports. Register banking is the method of using a single name to access multiple different physical registers depending on the operating mode. Register files may be clubbed together as register banks. A processor may have more than one register bank. ARM processors have both banked and unbanked registers. While all modes always share the same physical registers for the first eight general-purpose registers, R0 to R7,

6600-467: The same time with a context switch. However, it did not support integer operations, and the integer register file still remained as such. Later, shadow register files were abandoned in newer designs in favor of the embedded market. The SPARC uses a "Shadow Register File Architecture" as well for its high-end line. It has up to 4 copies of integer register files (future, retired, scaled, and scratched, each containing 7 read and 4 write ports) and 2 copies of

6688-444: The same trick used between integer and floating-point). This was done in order to solve the register bottleneck that existed in the x86 architecture after micro-operation fusion is introduced, but it is still have 8 entries 32 bit architectural registers for total 32 bytes in capacity per file (segment register and instruction pointer remain within the file, though they are inaccessible by program) as speculative file. The second file

6776-420: The tables are for a minimal 1-pipeline and a maximal 16-pipeline configuration, except for the Reality, which was restricted to single pipe operation. SGI Onyx SGI Onyx is a series of visualization systems designed and manufactured by SGI , introduced in 1993 and offered in two models, deskside and rackmount , codenamed Eveready and Terminator respectively. The Onyx's basic system architecture

6864-476: The texture memory. The SDRAMs used are 16 bits wide and have separate address and data buses. SDRAMs with a capacity of 4 Mb are used by Raster Manager boards with 16 MB of texture memory while 16 Mb SDRAMs are used by Raster Manager boards with 64 MB of texture memory. The TM ASICs perform texel lookups in their SDRAMs according to the texel addresses issued by the TA ASIC. Texels from the TM ASICs are forwarded to

6952-552: The time; it would require multiple register files to achieve superscale. The ARM processor on the other hand does not integrate multiple register files to load/fetch instructions. ARM GPRs have no special purpose to the instruction set (the ARM ISA does not require accumulator, index, and stack/base points. Registers do not have an accumulator and base/stack point can only be used in thumb mode). Any GPRs can propagate and store multiple instructions independently in smaller code size that

7040-605: The top XIO port connected to the right pipeline and the bottom XIO port connected to the left pipeline. The Reality is a cost-reduced version of the InfiniteReality2 intended to provide similar performance. Instead of using the GE14-4 Geometry Engine board and the RM7-16 or RM7-64 Raster Manager boards, the Reality used the GE14-2 Geometry Engine board and the RM8-16 or RM8-64 Raster Manager boards. The GE14-2 has two Geometry Engine Processors, instead of four like

7128-548: The traditional shared memory bus -based Onyx using the POWERpath-2 bus, and the distributed shared memory network-based Onyx2 using the NUMAlink2 interconnect, the InfiniteReality had to have an interface that could provide similar performance on both platforms, which had a large difference in incoming bandwidth (200 MB/s versus 400 MB/s respectively). To this end, a Host Interface Processor , an embedded RISC core,

7216-573: The value directly before the decode stage. Though theoretically it will only need a shorter pipeline than Intel's SSE implementation, but generally the cost of branch prediction are much greater and higher missing rate than Intel, and it would have to take at least two cycles for its SSE instruction to be executed regardless of instruction wide, as early AMDs implementations could not execute both FP and Int in an SSE instruction set like Intel's implementation did. Unlike Alpha , SPARC , and MIPS that only allows one register file to load/fetch one operand at

7304-406: The x86 manufacturers like Cyrix, VIA, DM&P, and SIS used the same mechanism as well, resulting in a lack of integer performance without register renaming for their in-order CPU. Companies like Cyrix and AMD had to increase cache size in hope to reduce the bottleneck. AMD's SSE integer operation work in a different way than Core 2 and Pentium 4; it uses its separate renaming integer register to load

7392-457: The x87's push stack. This, however, led to the FPU being unusable while using MMX , and the processor had to run the instructions by itself. On P6, the instruction independently can be stored and executed in parallel in early pipeline stages before decoding into micro-operations and renaming in out-of-order execution. Beginning with P6 , all register files do not require additional cycle to propagate

7480-539: Was designed to render complex scenes in high-quality at 60 frames per second, roughly two to four times the performance of the RealityEngine it replaced. It was designed explicitly for use in conjunction with the OpenGL graphics library and implements most of the OpenGL pipeline in hardware. The implementation is partitioned into Geometry (also known as the Geometry Engine ), Raster Memory (also known as

7568-618: Was introduced in 2000 along with the Onyx 3000 to supersede the InfiniteReality2. It was used in the Onyx2 and Onyx 3000 visualization systems. The only improvement over the previous implementation was replacement of the RM9-64 Raster Manager with the RM10-256 Raster Manager, which has 256 MB of texture memory, four times that of the previous raster manager. When maximally configured with four Raster Managers,

7656-399: Was introduced in late 1996. It is identical to the InfiniteReality architecturally, but differs mechanically as the Onyx2's Origin 2000 -based card cage is different from the Onyx's Challenge -based card cage. Introduced by the InfiniteReality2 is an interface scheme that is used in rackmount Onyx2 or later systems. Instead of being connected to the host system via a FCI cable, the board set

7744-563: Was later merged with the floating-point register file after a 128-bit XMM register debuted in Pentium III, but the XMM register file is still located separately from x86 integer register files. Later P6 implementations (Pentium M, Yonah) introduced a "Shadow Register File Architecture" that expanded to 2 copies of dual-ported integer architectural register files and consist with context switch (between future and retired file and scaled file using

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