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→Week 12 Deliverables
|2||Sep 12||[[#Week 2 - Class I|Introduction to 6502 Assembly]]||[[#Week 2 - Class II|6502 Math / Jumps, Branches, and Subroutines]]||[[#Week 2 Deliverables|Lab 2]]
|-
|3||Sep 19||[[#Week 3 - Class I|6502 Strings]]||[[#Week 3 - Class II|6502 String Input / Building Code / : Make and Makefiles / Autotools and Friends]]||[[#Week 3 Deliverables|Lab 3]]
|-
|4||Sep 26||[[#Week 4 - Class I|Compiler Optimizations]]||[[#Week 4 - Class II|ELF Files Building Code: Compiler Options, GNU Autotools/ Shared LibariesAutomake]]||[[#Week 4 Deliverables|Lab 3, September blog posts]]
|-
|5||Oct 3||[[#Week 5 - Class I|Introduction to 64-bit Architectures and Assembly Language (x86_64 and AArch64)]]||[[#Week 5 - Class II|Memory on 64-bit Systems]]||[[#Week 5 Deliverables|Lab 34]]
|-
|6||Oct 10||[[#Week 6 - Class I|Single Instruction, Multiple Data (SIMD) / Scalable Vector Extensions (SVE/SVE2)Mid-semester Sync Discussion]]||[[#Week 6 - Class II|Indirect Functions (GCC ifunc)Algorithm Selection / In-line Assembler / SIMD]]||[[#Week 6 Deliverables|Lab 45]]
|-
|7||Oct 17||[[#Week 7 - Class I|Project IntroductionExploring 64-bit Code]]||[[#Week 7 - Class II|Project SelectionSVE2]]||[[#Week 7 Deliverables|Lab Wrap up lab 5]]
|-
|Reading||Oct 24||style="background: #f0f0ff" colspan="3" align="center"|Reading Week
|-
|8||Oct 31||[[#Week 8 - Class I|Optimization Trade-Offs / Algorithm Selection/ Inline Assembler / SIMD]]||[[#Week 8 - Class II|Scalable Vector Extensions (SVE/SVE2) via Inline Assemblerand C Intrinsics]]||[[#Week 8 Deliverables|Lab 6, October blog posts]]
|-
|9||Nov 7||[[#Week 9 - Class I|GNU ifunc & Project DiscussionOverview]]||[[#Week 9 - Class II|Demo/discussion of SVE2 ExamplesProject Detail]]||[[#Week 9 Deliverables|Blog about ifunc and your project work]]
|-
|10||Nov 14||[[#Week 10 - Class I|Project DiscussionTips]]||[[#Week 10 - Class II|Advanced Memory Barriers]]||[[#Week 10 Deliverables|Blog about project work]]
|-
|11||Nov 21||[[#Week 11 - Class I|Project DiscussionTechniques]]||[[#Week 11 - Class II|Advanced Memory SystemsProject Demo]]||[[#Week 11 Deliverables|Blog about project work]]
|-
|12||Nov 28||[[#Week 12 - Class I|Project DiscussionBenchmarking]]||[[#Week 12 - Class II|Compiler TechnologyStep-by-Step Project Minimum Requirements]]||[[#Week 12 Deliverables|Blog about project work, November blog posts]]
|-
|13||Dec 5||[[#Week 13 - Class I|Enhancing Your Project Discussion]]||[[#Week 13 - Class II|Final project instructionsProject Discussion]]||[[#Week 13 Deliverables|Blog about project work; Project Stage 2 due Thursday December 8 at Noon]]
|-
|14||Dec 12||[[#Week 14 - Class I|Future Directions in Architecture]]||style="background: #f0f0ff"|(No class)||[[#Week 14 Deliverables|Project Stage 3, December blog posts]]
*** [[Endian|Endianness]]
** Code that takes advantage of platform-specific features
* Reasons for writing code in Assembly Langauge Language include:
** Performance
** [[Atomic Operation|Atomic Operations]]
===== Build Process =====
Building software is a complex task that many developers gloss over. The simple act of compiling a program invokes a process with five or more stages, including pre-proccessingprocessing, compiling, optimizing, assembling, and linking. However, a complex software system will have hundreds or even thousands of source files, as well as dozens or hundreds of build configuration options, auto configuration scripts (cmake, autotools), build scripts (such as Makefiles) to coordinate the process, test suites, and more.
The build process varies significantly between software packages. Most software distribution projects (including Linux distributions such as Ubuntu and Fedora) use a packaging system that further wraps the build process in a standardized script format, so that different software packages can be built using a consistent process.
*** Logically: false or true.
** Binary numbers are resistant to errors, especially when compared to other systems such as analog voltages.
*** To represent the numbers 0-10 as an analog electical electrical value, we could use a voltage from 0 - 10 volts. However, if we use a long cable, there will be signal loss and the voltage will drop: we could apply 10 volts on one end of the cable, but only observe (say) 9.1 volts on the other end of the cable. Alternately, electromagnetic interference from nearby devices could slightly increase the signal.
*** If we instead use the same voltages and cable length to carry a binary signal, where 0 volts == off == "0" and 10 volts == on == "1", a signal that had degraded from 10 volts to 9.1 volts would still be counted as a "1" and a 0 volt signal with some stray electromagnetic interference presenting as (say) 0.4 volts would still be counted as "0". However, we will need to use multiple bits to carry larger numbers -- either in parallel (multiple wires side-by-side), or sequentially (multiple bits presented over the same wire in sequence).
* Integers
*** Instead of fixed-length numbers, variable-length numbers are used, with the most common values encoded in the smallest number of bits. This is an effective strategy if the distribution of values in the data set is uneven.
** Repeated sequence encoding (1D, 2D, 3D)
*** Run length encoding is an encoding scheme that records the number of repeated values. For example, fax messages are encoded as a series of numbers representing the number of white pixels, then the number of black pixels, then white pixels, then black pixels, alternating to the end of each line. These numbers are then represented with adaptive artithmetic arithmetic encoding.
*** Text data can be compressed by building a dictionary of common sequences, which may represent words or complete phrases, where each entry in the dictionary is numbered. The compressed data contains the dictionary plus a sequence of numbers which represent the occurrence of the sequences in the original text. On standard text, this typically enables 10:1 compression.
** Decomposition
*** Compound audio wavforms waveforms can be decomposed into individual signals, which can then be modelled as repeated sequences. For example, a waveform consisting of two notes being played at different frequencies can be decomposed into those separate notes; since each note consists of a number of repetitions of a particular wave pattern, they can individually be represented in a more compact format by describing the frequency, waveform shape, and amplitude characteristics.
** Palletization
*** Images often contain repeated colours, and rarely use all of the available colours in the original encoding scheme. For example, a 1920x1080 "full HD" image contains about 2 million pixels, so if every pixel was a different colour, there would be a maximum of 2 million colours. But it's likely that many of the pixels in the image are the same colour, so there might only be (perhaps) 4000 colours in the image. If each pixel is encoded as a 24-bit value, there are potentially 16 million colours available, and there is no possibility that they are all used. Instead, a palette can be provided which specifies each of the 4000 colours used in the picture, and then each pixel can be encoded as a 12-bit number which selects one of the colours from the palette. The total storage requirement for the original 24-bit scheme is 1920*1080*3 bytes per pixel = 5.9 MB. Using a 12-bit pallette, the storage requirement is 3 * 4096 bytes for the palette plus 1920*1080*1.5 bytes for the image, for a total of 3 MB -- a reduction of almost 50%
# Follow the [[SPO600 Communication Tools]] set-up instructions.
# Optional (strongly recommended): [[SPO600 Host Setup|Set up a personal Linux system]].
# Optional: If you have an AArch64 development board (such as a Raspberry Pi 4, Raspberry Pi 400, or [http://96boards.org 96Boards] device), consider installing a 64-bit Linux operating system such as Fedora on it.
# Start work on [[SPO600 Code Review Lab|Lab 1]]. Blog your work.
== Week 2 ==
{{Admon/tip|Follow the Links!|To get the full benefit of the following material, please follow the links embedded within it. For additional detail, see the Category links at the bottom of those pages -- for example, the [[Category:Computer Architecture|Computer Architecture]] category linked from many of the following pages has over 30 pages of content.}}
* Although we program computers in a variety of languages, they can really only execute one langaugelanguage: [[Machine Language]], which is encoded in an architecture-specific binary code, sometimes called object code.
* Machine language is not easy to read. [[Assembly Language]] corresponds very closely to machine language, but is (sort of!) human-readable.
* Assembly language is converted into machine code by a particular type of compiler called an [[Assembler]] (sometimes the language itself is also referred to as "Assembler").
==== 6502 ====
Modern processors are complex - the reference manual for 64-bit ARM processors is over 11000 pages long! - so we're going to look at assembly lanaguage language on a much simpler processor to get started. This processor is the 6502, a processor used in many early home and personal computers as well as video game systems, including the Commodore PET, VIC-20, C64; the Apple II; the Atari 400 and 800 computers and 2600 video game systems; and many others.
* Introduction to the [[6502]] (note the Resources links on that page)
* Introduction to the [[6502 Addressing Modes]]
* Information about the [[6502 Emulator]] which we will use in this course, and some [[6502_Emulator_Example_Code|example code]]
* Link to the actual [http://6502.cdot.system systems 6502 emulator]
==== Lab 2 ====
# Study the [[6502 Instructions - Introduction|6502 Instructions]] and [[6502 Addressing Modes]] and make sure you understand what each one does.
# Complete [[6502 Assembly Language Lab|Lab 2]] and blog your results.
== Week 3 ==
==== Video ====
* No [https://web.microsoftstream.com/video/a4707dd6-b0df-409b-8168-58ec21a06c1b Summary video is available due to issues with the audio.from class on 6502 Strings] ==== Lab ====* The links below contain the same information.[[6502 Math and Strings Lab]] (Lab 3)
=== Week 3 - Class II ===
==== Videos Video ====* 6502 Assembly Language** [https://web.microsoftstream.com/video/9caa5e8d-0f15-4b8b-9293-0151c82f77b1 6502 String Input]** [https://web.microsoftstream.com/video/6a645edd-3537-4910-843c-6d32f6678e79 A 6502 Assembly Hack]** [https://web.microsoftstream.com/video/1775931c-b9eb-4b2a-a7bd-598d7d725853 6502 Assembly Sample Code]* 6502 - Additional Resources** [https://web.microsoftstream.com/video/792a16536a645edd-36a03537-4f154910-b3fc843c-36461dbbb969 6d32f6678e79 An old video on the basics of using the 6502 Jumps, Branches, and ProceduresEmulator]** [https://web.microsoftstream.com/video/a60f8b98f22220d6-60579c87-4c834d23-aecbaaf8-b40eb7f5bd8f 95f681756c41 6502 Characters & StringsAssembler Directives] - using "define" and "dcb"* Building code: make** [https://web.microsoftstream.com/video/6b83e243-2b82-4afe-848e-e8c26881199a make and Makefiles]
==== More 6502 Assembly Resources ====* [[Make and Makefiles]]* 6502 Example Code** [[6502 Jumps, Branches, and ProceduresEmulator Example Code]] page on this wiki** Chris Tyler's [https://github.com/ctyler/6502js-code/ 6502js-code] repository on GitHub (includes Wordle-like example)** [http://6502asm.com/ 6502asm.com] - a site with an early version of the 6502 Emulator - see the "Examples" pull-down menu (these examples will run in [[http://6502.cdot.systems|our emulator]]
==== Lab Week 3 =Deliverables ===* [[6502 Math and Strings Lab|Lab 3]] (Lab 3)* Note that September blog posts are due at the end of next week, so don't get behind in your blogging
== Week 4 ==
==== Video ====
* [https://web.microsoftstream.com/video/05311ea330fa002e-85369e3d-4b7841f6-ace395db-438902d78d67 36832a8a509c Edited summary videoClass Summary Video]* '''Reminder:''' the videos are a summary/recap only - they're no substitute for attending, taking notes, and asking questions in class!
==== Compiler Optimizations Reading Resources ====
* [[Compiler Optimizations]]
* Connecting to course servers
** [[SPO600 Servers]]
** [[SSH]]
** [[Screen Tutorial|Screen utility]] - allows disconnection/reconnection to remote host
=== Week 5 4 - Class II === ==== Video ====* Video content will be delayed due to a storage error[https://web.microsoftstream.com/video/48f2d7a8-67d3-4e49-b02e-a29e7d9b656c Building Code: Compiler Options]* Please continue work on [https://web.microsoftstream.com/video/38b050c6-6aad-4e64-b564-95ceb53adc7c Building Code: Automake/Autotools (configure scripts)] ==== Resouces ====* [6502 Math and Strings Lab|Lab 3https://www.gnu.org/software/automake/manual/html_node/index.html GNU Autotools/Automake]* [https://gcc.gnu.org/onlinedocs/ GCC Manual]
=== Week 4 Deliverables ===
* '''By the end of the day on Tuesday, February 1:''' Blogs for January September blogs are due this weekend (including any labs you're submitting for JanuarySunday, October 2 at 11:59 pm). Make sure you've submitted the [[SPO600 Communication Tools|web form]] with your blog URL so I can find it!* Finish [[6502 Math and Strings Lab|Lab 3]]* Continue to blog
== Week 5 ==
==== Video ====
* No recording of the live session is available (bad audio)* Pre-recorded lecture/demo: [https://web.microsoftstream.com/video/466bc3a1fe744d30-6729f947-434d433d-b51fb9f3-33d4fbb145c5 Make and Makefilesf5284e6fb2ad Class Summary Video]
==== Notes Resources ====* [[Make Assembly Language]]* [[ELF]] file format* [[X86_64 Register and MakefilesInstruction Quick Start]]* [[Aarch64 Register and Instruction Quick Start]]===== Compiler Options =====* ARM 64-bit CPU Instruction Set and Software Developer Manuals* (Modern compilers are similar in options, for the sake of this discussion I'm focusing on the GNU C Compiler (gcc), part of the GNU Compiler Collection)ARM Aarch64 documentation* There are hundreds of compiler features available, many of which are optimization options* [http://developer.arm.com/ ARM Developer Information Centre]* These features can be controlled from the compiler command line** [https://developer.arm.com/docs/den0024/latest ARM Cortex-A Series Programmer’s Guide for ARMv8-A]** To enable a feature, specify <code>-f</code> and the option name: <code>-f* The ''builtinshort''<guide to the ARMv8 instruction set: [https://code>www.element14.com/community/servlet/JiveServlet/previewBody/41836-102-1-229511/ARM.Reference_Manual.pdf ARMv8 Instruction Set Overview] ("ARM ISA Overview")** To disable a feature, specify <code>-f</code> and then <code>no-</code> and the option name: <code>-f* The ''no-builtinlong''<guide to the ARMv8 instruction set: [https:/code>* Example: gcc /developer.arm.com/docs/ddi0487/latest/arm-fbuiltin architecture-falignreference-functions manual-noarmv8-callerfor-saves ''foo''.c armv8-o foo* To see the available optimization features and what each does, view the gcc manpage and/or gcc manual* It's a pain to specify hundreds of <code>-f</code> options on the command linearchitecture-profile ARM Architecture Reference Manual ARMv8, so these are grouped into commonlyfor ARMv8-used sets. The sets can be specified with the <code>-O</code> compiler option A architecture profile] (note that that is a capital letter "O", not a lowercase "o" nor a zero "0ARM ARM"), followed by an optimization level:** -O0 [https: almost no optimization** //developer.arm.com/docs/ihi0055/latest/procedure-O1 : optimizations that can be quickly performed** call-O2 : all of the normal optimizations that can be safely applied to all programs (this is the usual default optimization level)** standard-O3 : all normal optimization, including some that may in rare cases cause changes to the operation of the program (for example, counting +0 and -0 as the same number -arm- which is fine in the vast majority of cases, but might interfere with 64-bit-architecture Procedure Call Standard for the correct operation of some scientific calculations)** ARM 64-Os : optimize for smallest size bit Architecture (of both the executable and the memory usage while executingAArch64)]** -Ofast : optimize for highest speed, even at the cost of more memory usagex86_64 Documentation** -Og [https: optimize for debugging //developer.amd.com/resources/developer-guides- avoid optimizations that will excessively convolute manuals/ AMD Developer Guide and Manuals](see the codeAMD64 Architecture section, making it harder to see particularly the correlation between the source code ''AMD64 Architecture Programmer’s Manual Volume 3: General Purpose and the object codeSystem Instructions'')* Note that the set of optimizations considered "safe" may vary over time - for example, vector optimization were previously considered unsafe (<code>-O3<* [http:/code>) in the gcc compiler, but with improvements and testing are not considered safe and are therefore included in the <code>-O2</code> level in newer versions of gccwww.intel.* You can specify a group of options with <code>-O<com/content/www/us/code> and override the use of individual options with <code>-f<en/code> by placing the <code>-O<processors/code> group first: gcc architectures-O2 software-fnodeveloper-builtin foomanuals.c -o foohtml Intel Software Developers Manuals]* To see the optimizations that will be applied by a given set of commandGAS Manual -line options Using as, use <code>-Q --help=optimizers<The GNU Assembler: https://sourceware.org/binutils/docs/as/code> to query the optimization list that the compiler will use: gcc -O1 -Q --help=optimizers | less
=== Week 5 - Class II ===
==== Video ====
* [https://web.microsoftstream.com/video/915547781bcab47b-ac0f514a-49284f23-8a8bbdd4-f4636b96a427 x86_64 & AArch64 Introduction - Registersf73662a0673f Paged Memory Systems]
* [https://web.microsoftstream.com/video/880fb0f8-1084-457a-92e0-80f04ad62463 Memory Alignment and Performance]
=== Resources = Lab 4 ====* [[X86 SPO600 64 Register and Instruction Quick Start]]* [[AArch64 Register and Instruction Quick Start]]* [[Computer Architecture-bit Assembly Language Lab]](Lab 4)
=== Week 5 Deliverables ===
* Finish [[6502 Math and Strings SPO600 64-bit Assembly Language Lab|Lab 34]]* Continue to blog
== Week 6 ==
=== Week 6 - Class I ===
=== Week 6 - Class II ===
==== Videos Video ====* [https://web.microsoftstream.com/video/8c3c1353d208a737-57297777-42174b5a-b1bab276-371410f14ad4 64-Bit 1b19dc78145c Inline Assembly Language ] - Inserting assembly language code into programs written in other languages (in this case, C)* [https://web.microsoftstream.com/video/f60b92c6-9db3-4f57-b0b9-7c35ea0c054f Single Instruction, Multiple Data (SIMD)]* [https://web.microsoftstream.com/video/2a82da88-bf5b-4112-953a- Part II7408fbab30c1 Algorithm Selection and Benchmarking]
==== Reading Lab 5 ====* [[Assembly Language]]* [[Assembler Basics]https://wiki.cdot.senecacollege.ca/wiki/SPO600_Algorithm_Selection_Lab Algorithm Selection Lab](Lab 5)
=== Week 6 Deliverables ===
* [[SPO600 64-bit Assembly Language https://wiki.cdot.senecacollege.ca/wiki/SPO600_Algorithm_Selection_Lab Lab|Lab 4]5]* Continue to Blog
== Week 7 ==
==== Video ====
* A Video summary video will be posted after editing
=== Week 7 - Class II ===
==== Reading ====
* [[Inline Assembly LanguageSVE2]]
==== Lab SVE2 Demonstration ====* Code available here: https://github.com/ctyler/sve2-test* This is an implementation of a very simple program which takes an image file, adjusts the red/green/blue channels of that file, and then writes an output file. Each channel is adjusted by a factor in the range 0.0 to 2.0 (with saturation).* The image adjustment is performed in the function <code>adjust_channels()</code> in the file <code>adjust_channels.c</code>. There are three implementations:*# A basic (naive) implementation in C. Although this is a very basic implementation, it is potentially subject to autovectorization.*# An implementation using inline assembler for SVE2 with strucure loads.*# An implementation using inline assembler for SVE2 with an interleaved factor table.*# An implementation using ACLE compile intrinsics.* The implementation built is dependent on the value of the ADJUST_CHANNEL_IMPLEMENTATION macro.* The provided Makefile will build four versions of the binary -- one using each of the four implementations -- and it will run through 3 tests with each binary. The tests use the input image file <code>tests/input/bree.jpg</code> (a picture of a cat) and place the output in the files <code>tests/output/bree[1234][SPO600 Algorithm Selection Lababc]] (Lab .jpg</code>. The output files are processed with adjustment factors of 0.5/0.5/0.5), 1.0/1.0/1.0, and 2.0/2.0/2.0.* '''Please examine, build, and test the code, compare the implementations, and note how it works - there are extensive comments in the code, especially for implementation 2.'''* Your observations about the code might make a good blog post!
=== Week 7 Deliverables ===
* Complete [[SPO600 Algorithm Selection 64-bit Assembly Language Lab|Lab 4]] and [https://wiki.cdot.senecacollege.ca/wiki/SPO600_Algorithm_Selection_Lab Lab 5]]* '''Note:''' Blog for February Remember that October blogs are due at 11:59 pm on February 28 (Tuesday). I'll be looking for an average of 1-2 blog posts per week, or 4-8 blog posts for February. Please review your posts for accuracy and completenesssoon.
== Week 8 ==
==== Video ====
* [https://web.microsoftstream.com/video/333ff7dff67c0185-7c82fc67-48c743fb-8051ac39-57cae26792a8 SIMD -39a04592c849 Edited summary video] ==== Reading ====* [[SVE2]] ==== Lab ====* [[SPO600 SVE2 Lab]Summary Video] (Lab 6)
=== Week 8 - Class II ===
==== Video ====
* [https://web.microsoftstream.com/video/ad72567ea6b892e4-047db408-4dda4bc7-9f249fc1-0c525429c7d1 Searching a Codebase] === Week 8 Deliverables ===* Blog about your [[SPO600 d78e4efb8e0e SVE & SVE2 Lab|Lab 6]] == Week 9 == === Week 9 - Class I === ==== Video ====* Edited Summary video: [https://web.microsoftstream.com/video/b9ccfc5f-f816-45af-828f-98f5fad5c8c8 Project Discussion 1] === Week 9 - Class II ===* No content posted. == Week 10 == === Week 10 - Class I === ==== Video ====* Summary video: [https://web.microsoftstream.com/video/058bf7e4-ba17-47a0-9db9-9221a24da548 Project Discussion 2] === Week 10 - Class II === ==== Videos ====* [https://web.microsoftstream.com/video/b62a6499-012b-4203-b320-126b978e6ae3 GCC and SVE2] - A discussion of compiler flags, macros, pre-processor directives, and disassembly analysis that may be useful in project stage 2.* [https://web.microsoftstream.com/video/52c0d800-9618-46ac-8a5e-1a5477b5e4f0 Bitwise Operations] - this video covers AND, OR, XOR/EOR, and NOT operations. It should be review, but I've seen these operations misused a few times lately so it may be useful to you, especially if you are not familiar with the use of masks with these operations. === Week 10 - Deliverables ===* Blog about your [[Winter 2022 SPO600 Project|project work]].* '''Note:''' Your [[Winter 2022 SPO600 Project|Project Stage 1]] is due on Monday, March 28 by midnight. == Week 11 == === Week 11 - Class I === ==== Videos ====* [https://web.microsoftstream.com/video/5f633a25-c478-4aab-af90-c447d581a631 Project Discussion 3] - An edited recording of the March 28, 2022 SPO600 class.* [https://web.microsoftstream.com/video/b197e528-3385-41ef-b648-7041d054c0d2 Benchmarking and Profiling] - An optional video that may be useful to some projects in Stage 2. This video discusses benchmarking (overall program performance analysis) and profiling (per-function/per-method performance analysis) principles and techniques. (This is an edited version of a previous-semester video. There are a couple of small audio and video glitches in the recording).
==== Reading ====
* [https://locklessinc.com/articles/vectorize/ Auto-vectorization with GCC 4.7] - Although based on an earlier version of GCC (and a number of new features have been added to the GCC autovectorizer since this article was written), it discusses some of the techniques and code adjustments that may be required to get the GCC compiler to vectorize code. Note that the <code>-fopt-info-vec-all</code> or <code>-fopt-info-vec-missed</code> options are useful in conjunction with this technique, as they will cause the compiler to emit information about the vectorization decisions that it is making.* [https://www.phoronix.com/scan.php?page=news_item&px=GCC-12-Auto-Vec-O2 GCC 12 Enables Auto-Vectorization for -O2 Optimization Level] - a short news article from October 2021 regarding the [https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=2b8453c401b699ed93c085d0413ab4b5030bcdb8 commitSVE2] that added autovectorization to the <code>-O2</code> optimization level, which is the default for many projects. GCC12 is expected to ship in April 2022, according to a recent [https://gcc.gnu.org/pipermail/gcc/2022-January/238136.html status update]. === Week 11 - Class II ===
==== SVE2 Demonstration ====
* Code available here: https://github.com/ctyler/sve2-test
** You can clone this to israel.cdot.systems with: <code>git clone https://github.com/ctyler/sve2-test.git</code>
* This is an implementation of a very simple program which takes an image file, adjusts the red/green/blue channels of that file, and then writes an output file. Each channel is adjusted by a factor in the range 0.0 to 2.0 (with saturation).
* The image adjustment is performed in the function <code>adjust_channels()</code> in the file <code>adjust_channels.c</code>. There are three implementations:
*# A basic (naive) implementation in C. Although this is a very basic implementation, it is potentially subject to autovectorization.
*# An implementation using inline assembler for SVE2with strucure loads.*# An implementation using inline assembler for SVE2 with an interleaved factor table.*# (Future) An implementation using ACLE compile intrinsics.
* The implementation built is dependent on the value of the ADJUST_CHANNEL_IMPLEMENTATION macro.
* The provided Makefile will build two four versions of the binary, -- one using implementation 1 (named <code>image_adjust1</code>) and one using implementation 2 (named <code>image_adjust2</code>), each of the four implementations -- and it will run through 3 tests with each binary. The tests use the input image file <code>tests/input/bree.jpg</code> (a picture of a cat) and place the output in the files <code>tests/output/bree[121234][abc].jpg</code>. The output files are processed with adjustment factors of 0.5/0.5/0.5, 1.0/1.0/1.0, and 2.0/2.0/2.0.
* '''Please examine, build, and test the code, compare the implementations, and note how it works - there are extensive comments in the code, especially for implementation 2.'''
* Your observations about the code might make a good blog post!
=== Week 11 - 8 Deliverables ===* Blog about Continue your project work.blogging* Include blogging on SVE/SVE* The second group of blog posts is due on or before this Sunday (November 6, 11:59 pm)
== Week 9 ==
==== Video ====
* [https://web.microsoftstream.com/video/00172f3b28a4f8e7-f0cbc96c-486f4662-bf159adc-42c73e8916b4 SVE2 Examples8d67aa409868 Edited summary] - Summary video of the SPO600 class on Tuesday, April 5.
==== SVE2 Demonstration iFunc ====* The SVE2 [https://github.com/ctyler/sve2-test example code] has been extended with an additional inline assembley implementation, plus an ACLE implementation.
=== Week 12 - Deliverables = Reading/Resources ====* Continue to blog about your project work* Project Stage 2 will be due on '''Wednesday, April 13''' (11:59 pm EDT).
=== Week 13 9 - Class I II ===
==== Video ====
* [https://web.microsoftstream.com/video/274ee2d2edc09b0a-a19c1a7f-4d1245d1-8c1ba27e-78141cfb4566 Memory Systems7f4901bba03d Edited summary video] - '''Important!''' This video contains a detailed discussion of the requirements for the course project.** Project discussion starts at beginning of video** Demo of what the project needs to do (manually performing the same steps) starts at 0:27:47** Recap/summary videoof the demo starts around 1:02:05
=== Week 13 - Class II = Project ====* Good Friday - no class[[Fall 2022 SPO600 Project]]
=== Week 13 9 Deliverables ===* Continue to post Investigate the iFunc example code* Blog about your investigation* Start blogging about your project.
== Week 14 10 ===== Week 10 - Class I ======= Video ====* [https://web.microsoftstream.com/video/76aae456-492d-4edd-a735-5009caf59bf6 Summary Video] - Tips and techniques for working productively in a remote aarch64 Linux system.=== Week 10 - Class II ===* A discussion of of Advanced Memory Systems* No video available at this time* Not directly related to the course project=== Week 10 Deliverables ===* Blog about your project work.
== Week 11 ===== Week 14 11 - Class I ======= Video ====* [https://web.microsoftstream.com/video/29183138-9105-4ca6-b085-7ac84f19f7a3 Summary Video] - Techniques you can use in your project.=== Week 11 - Class II ======= Video ====* [https://web.microsoftstream.com/video/4a29385e-e924-4ef1-a5eb-b526e3aa6390 Summary Video] - A demonstration of one solution to the course project.=== Week 11 Deliverables ===* Blog about your project work.
== Week 12 ==
=== Week 12 - Class I ===
* A discussion of benchmarking
* No video available at this time
* Not directly related to the course project
=== Week 12 - Class II ===
==== Video ====
* [https://web.microsoftstream.com/video/fcc73002-b59c-4bc7-b0e6-c73706b492e8 Summary Video] - Step-by-Step discussion of the minimum requirements for a successful project
==== Minimum Requirements for a Successful Project ====
* Remember: This project is about building a ''tool'' that processes C source code. The tool itself can be in any suitable computer language. It is recommended that you use a language that can manipulate text easily. The tool will receive an input file containing a C function. The tool will output a modified file(s) with ifunc capability for asimd/sve/sve2 computers.
* Requirements for a minimum implementation:
# Find the protype and function name by analyzing the C function.
#* Example name: <code>adjust_channels</code>
#* Example prototype: <code>void adjust_channels(unsigned char *image,int x_size,int y_size,float red_factor,float green_factor,float blue_factor);</code>
#* Hint/suggestion: compiling the function file with the <code>-S</code> option will produce an assembly-language output file. You can parse this file for lines like <code>.type adjust_channels, %function</code> to find the function name(s).
#* Hint/suggestion #2: the <code>makeheaders</code> utility can produce a header file from an C source code input file. It is easier to find the function prototypes in the header file than in the C source file.
# Place the prototype into the output file, adding the ifunc atttribute and resolver name. This produces the indirect function.
#* Example indirect function: <code>__attribute__ (( ifunc("''name_of_resolver_function''") )) void adjust_channels(unsigned char *image,int x_size,int y_size,float red_factor,float green_factor,float blue_factor);</code>
# Repeat these next two steps three times, once for each target (see the table below)
## Place a GCC pragma directive into the output file to select one of the three targets: <code>#pragma GCC target arch="''put the target architecture string here''"</code>
## Paste in the function, changing the function name so that the various versions don't conflict. For example, you could append a suffix identifying the architecture target, changing the function name <code>adjust_channels</code> to something like <code>adjust_channels_sve</code>.
##* Tip: After the last function, add a pragma to switch the compiler back to targeting basic <code>armv8-a</code>
# Add the resolver function, being sure to include the header file <code><nowiki><sys/auxv.h></nowiki></code> so that we can access the auxilliary vector (and therefore the description of available hardware capabilities).
static void (*''name_of_resolver_function''(void)) {
long hwcaps = getauxval(AT_HWCAP);
long hwcaps2 = getauxval(AT_HWCAP2);
printf("\n### Resolver function - selecting the implementation to use for foo()\n");
if (hwcaps2 & HWCAP2_SVE2) {
return adjust_channels_sve2;
} else if (hwcaps & HWCAP_SVE) {
return adjust_channels_sve;
} else {
return adjust_channels_asimd;
}
};
<ol><li value="5"> Build the software using the output file in place of the input file.
<li> Test it thoroughly! Use your tool and compile the output. Look at the final binary to check for asimd/sve/sve2 code, and make sure the program runs in both contexts (run the binary directly to test it in asimd mode, and use the qemu-aarch64 tool to run the binary in sve2 mode).
<li> Write it up in one or more blog posts.
* The mark assigned will depend on:
** The quality of the implementation - For example, does it accept various input files and process them correctly? Are the output files reliably usable? Is the tool user-friendly?
** The amount and quality of the testing - For example, have you demonstrated that the tool works correctly? Can you show the asimd, sve, and sve2 code in the compiled binary?
** The quality of the writing - For example, have you fully explained the code? Have you documented how to use your tool with clear, step-by-step instructions? Is the code provided in a form that makes it easy to test?
** If the basic operation of the program is good, bonus marks may be assigned for additional features and for overcoming the (permitted) limitations. See the project page for details.
</ol>
==== Build Targets ====
These are the build targets:
{|cellspacing="0" width="100%" cellpadding="5" border="1"
|-
!Name!!Abbreviation!!Typical GCC Target String!!Description
|-
|Advanced SIMD||asimd||armv8-a||Basic "Advanced SIMD" implementation present in all aarch64 systems. Fixed-length 128-bit SIMD implementation.
|-
|Scalable Vector Extensions||sve||armv8-a+sve||Original version of the Scalable Vector Extensions. Variable-length 128-to-2048 bit SIMD implementation with predicate registers and first-fault load/store operations.
|-
|Scalable Vector Extensions version 2||sve2||armv8-a+sve2 (also armv9-a)||New, expanded version of the Scalable Vector Extensions used in Arm architecture version 9 systems. Has the same implementation details as sve, but with many additional instructions, such as operations useful for digital signal processing (dsp).
|}
GCC target strings may be used:* On the GCC command line, using the <code>-march=...</code> option* In function attributes: <code>__attribute__(( target(Not available"...") ))</code>* In pragmas: <code>#pragma GCC target "..."</code>
=== Week 14 - Class II 12 Deliverables ===* Blog about your Project* November blog posts are due Sunday, December 4, at 11:59 pm.* Project Stage II is due next Thursday, December 8, at 12 noon.
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