How to Write Fast Code SIMD Vectorization, Part 1 18-645, Spring
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Review Memory Disambiguation Review Explicit Register Renaming
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The Instruction Set Architecture
Quiz 0 Lecture 2: The Instruction Set Architecture COS / ELE 375 Computer Architecture and Organization Princeton University Fall 2015 Prof. David August 1 2 Quiz 0 CD 3 Miles of Music 3 4 Pits and Lands Interpretation 0 1 1 1 0 1 0 1 As Music: 011101012 = 117/256 position of speaker As Number: Transition represents a bit state (1/on/red/female/heads) 01110101 = 1 + 4 + 16 + 32 + 64 = 117 = 75 No change represents other state (0/off/white/male/tails) 2 10 16 (Get comfortable with base 2, 8, 10, and 16.) As Text: th 011101012 = 117 character in the ASCII codes = “u” 5 6 Interpretation – ASCII Princeton Computer Science Building West Wall 7 8 Interpretation Binary Code and Data (Hello World!) • Programs consist of Code and Data • Code and Data are Encoded in Bits IA-64 Binary (objdump) As Music: 011101012 = 117/256 position of speaker As Number: 011101012 = 1 + 4 + 16 + 32 + 64 = 11710 = 7516 As Text: th 011101012 = 117 character in the ASCII codes = “u” CAN ALSO BE INTERPRETED AS MACHINE INSTRUCTION! 9 Interfaces in Computer Systems Instructions Sequential Circuit!! Software: Produce Bits Instructing Machine to Manipulate State or Produce I/O Computers process information State Applications • Input/Output (I/O) Operating System • State (memory) • Computation (processor) Compiler Firmware Instruction Set Architecture Input Output Instruction Set Processor I/O System Datapath & Control Computation Digital Design Circuit Design • Instructions instruct processor to manipulate state Layout • Instructions instruct processor to produce I/O in the same way Hardware: Read and Obey Instruction Bits 12 State State – Main Memory Typical modern machine has this architectural state: Main Memory (AKA: RAM – Random Access Memory) 1. -
Inside Intel® Core™ Microarchitecture Setting New Standards for Energy-Efficient Performance
White Paper Inside Intel® Core™ Microarchitecture Setting New Standards for Energy-Efficient Performance Ofri Wechsler Intel Fellow, Mobility Group Director, Mobility Microprocessor Architecture Intel Corporation White Paper Inside Intel®Core™ Microarchitecture Introduction Introduction 2 The Intel® Core™ microarchitecture is a new foundation for Intel®Core™ Microarchitecture Design Goals 3 Intel® architecture-based desktop, mobile, and mainstream server multi-core processors. This state-of-the-art multi-core optimized Delivering Energy-Efficient Performance 4 and power-efficient microarchitecture is designed to deliver Intel®Core™ Microarchitecture Innovations 5 increased performance and performance-per-watt—thus increasing Intel® Wide Dynamic Execution 6 overall energy efficiency. This new microarchitecture extends the energy efficient philosophy first delivered in Intel's mobile Intel® Intelligent Power Capability 8 microarchitecture found in the Intel® Pentium® M processor, and Intel® Advanced Smart Cache 8 greatly enhances it with many new and leading edge microar- Intel® Smart Memory Access 9 chitectural innovations as well as existing Intel NetBurst® microarchitecture features. What’s more, it incorporates many Intel® Advanced Digital Media Boost 10 new and significant innovations designed to optimize the Intel®Core™ Microarchitecture and Software 11 power, performance, and scalability of multi-core processors. Summary 12 The Intel Core microarchitecture shows Intel’s continued Learn More 12 innovation by delivering both greater energy efficiency Author Biographies 12 and compute capability required for the new workloads and usage models now making their way across computing. With its higher performance and low power, the new Intel Core microarchitecture will be the basis for many new solutions and form factors. In the home, these include higher performing, ultra-quiet, sleek and low-power computer designs, and new advances in more sophisticated, user-friendly entertainment systems. -
Simple Computer Example Register Structure
Simple Computer Example Register Structure Read pp. 27-85 Simple Computer • To illustrate how a computer operates, let us look at the design of a very simple computer • Specifications 1. Memory words are 16 bits in length 2. 2 12 = 4 K words of memory 3. Memory can be accessed in one clock cycle 4. Single Accumulator for ALU (AC) 5. Registers are fully connected Simple Computer Continued 4K x 16 Memory MAR 12 MDR 16 X PC 12 ALU IR 16 AC Simple Computer Specifications (continued) 6. Control signals • INCPC – causes PC to increment on clock edge - [PC] +1 PC •ACin - causes output of ALU to be stored in AC • GMDR2X – get memory data register to X - [MDR] X • Read (Write) – Read (Write) contents of memory location whose address is in MAR To implement instructions, control unit must break down the instruction into a series of register transfers (just like a complier must break down C program into a series of machine level instructions) Simple Computer (continued) • Typical microinstruction for reading memory State Register Transfer Control Line(s) Next State 1 [[MAR]] MDR Read 2 • Timing State 1 State 2 During State 1, Read set by control unit CLK - Data is read from memory - MDR changes at the Read beginning of State 2 - Read is completed in one clock cycle MDR Simple Computer (continued) • Study: how to write the microinstructions to implement 3 instructions • ADD address • ADD (address) • JMP address ADD address: add using direct addressing 0000 address [AC] + [address] AC ADD (address): add using indirect addressing 0001 address [AC] + [[address]] AC JMP address 0010 address address PC Instruction Format for Simple Computer IR OP 4 AD 12 AD = address - Two phases to implement instructions: 1. -
POWER-AWARE MICROARCHITECTURE: Design and Modeling Challenges for Next-Generation Microprocessors
POWER-AWARE MICROARCHITECTURE: Design and Modeling Challenges for Next-Generation Microprocessors THE ABILITY TO ESTIMATE POWER CONSUMPTION DURING EARLY-STAGE DEFINITION AND TRADE-OFF STUDIES IS A KEY NEW METHODOLOGY ENHANCEMENT. OPPORTUNITIES FOR SAVING POWER CAN BE EXPOSED VIA MICROARCHITECTURE-LEVEL MODELING, PARTICULARLY THROUGH CLOCK- GATING AND DYNAMIC ADAPTATION. Power dissipation limits have Thus far, most of the work done in the area David M. Brooks emerged as a major constraint in the design of high-level power estimation has been focused of microprocessors. At the low end of the per- at the register-transfer-level (RTL) description Pradip Bose formance spectrum, namely in the world of in the processor design flow. Only recently have handheld and portable devices or systems, we seen a surge of interest in estimating power Stanley E. Schuster power has always dominated over perfor- at the microarchitecture definition stage, and mance (execution time) as the primary design specific work on power-efficient microarchi- Hans Jacobson issue. Battery life and system cost constraints tecture design has been reported.2-8 drive the design team to consider power over Here, we describe the approach of using Prabhakar N. Kudva performance in such a scenario. energy-enabled performance simulators in Increasingly, however, power is also a key early design. We examine some of the emerg- Alper Buyuktosunoglu design issue in the workstation and server mar- ing paradigms in processor design and com- kets (see Gowan et al.)1 In this high-end arena ment on their inherent power-performance John-David Wellman the increasing microarchitectural complexities, characteristics. clock frequencies, and die sizes push the chip- Victor Zyuban level—and hence the system-level—power Power-performance efficiency consumption to such levels that traditionally See the “Power-performance fundamentals” Manish Gupta air-cooled multiprocessor server boxes may box. -
PIC Family Microcontroller Lesson 02
Chapter 13 PIC Family Microcontroller Lesson 02 Architecture of PIC 16F877 Internal hardware for the operations in a PIC family MCU direct Internal ID, control, sequencing and reset circuits address 7 14-bit Instruction register 8 MUX program File bus Select 8 Register 14 8 8 W Register (Accumulator) ADDR Status Register MUX Flash Z, C and DC 9 Memory Data Internal EEPROM RAM 13 Peripherals 256 Byte Program Registers counter Ports data 368 Byte 13 bus 2011 Microcontrollers-... 2nd Ed. Raj KamalA to E 3 8-level stack (13-bit) Pearson Education 8 ALU Features • Supports 8-bit operations • Internal data bus is of 8-bits 2011 Microcontrollers-... 2nd Ed. Raj Kamal 4 Pearson Education ALU Features • ALU operations between the Working (W) register (accumulator) and register (or internal RAM) from a register-file • ALU operations can also be between the W and 8-bits operand from instruction register (IR) • The operations also use three flags Z, C and DC/borrow. [Zero flag, Carry flag and digit (nibble) carry flag] 2011 Microcontrollers-... 2nd Ed. Raj Kamal 5 Pearson Education ALU features • The destination of result from ALU operations can be either W or register (f) in file • The flags save at status register (STATUS) • PIC CPU is a one-address machine (one operand specified in the instruction for ALU) 2011 Microcontrollers-... 2nd Ed. Raj Kamal 6 Pearson Education ALU features • Two operands are used in an arithmetic or logic operations • One is source operand from one a register file/RAM (or operand from instruction) and another is W-register • Advantage—ALU directly operates on a register or memory similar to 8086 CPU 2011 Microcontrollers-.. -
ARM Cortex-A* Brian Eccles, Riley Larkins, Kevin Mee, Fred Silberberg, Alex Solomon, Mitchell Wills
ARM Cortex-A* Brian Eccles, Riley Larkins, Kevin Mee, Fred Silberberg, Alex Solomon, Mitchell Wills The ARM CortexA product line has changed significantly since the introduction of the CortexA8 in 2005. ARM’s next major leap came with the CortexA9 which was the first design to incorporate multiple cores. The next advance was the development of the big.LITTLE architecture, which incorporates both high performance (A15) and high efficiency(A7) cores. Most recently the A57 and A53 have added 64bit support to the product line. The ARM Cortex series cores are all made up of the main processing unit, a L1 instruction cache, a L1 data cache, an advanced SIMD core and a floating point core. Each processor then has an additional L2 cache shared between all cores (if there are multiple), debug support and an interface bus for communicating with the rest of the system. Multicore processors (such as the A53 and A57) also include additional hardware to facilitate coherency between cores. The ARM CortexA57 is a 64bit processor that supports 1 to 4 cores. The instruction pipeline in each core supports fetching up to three instructions per cycle to send down the pipeline. The instruction pipeline is made up of a 12 stage in order pipeline and a collection of parallel pipelines that range in size from 3 to 15 stages as seen below. The ARM CortexA53 is similar to the A57, but is designed to be more power efficient at the cost of processing power. The A57 in order pipeline is made up of 5 stages of instruction fetch and 7 stages of instruction decode and register renaming. -
A Simple Processor
CS 240251 SpringFall 2019 2020 FoundationsPrinciples of Programming of Computer Languages Systems λ Ben Wood A Simple Processor 1. A simple Instruction Set Architecture 2. A simple microarchitecture (implementation): Data Path and Control Logic https://cs.wellesley.edu/~cs240/s20/ A Simple Processor 1 Program, Application Programming Language Compiler/Interpreter Software Operating System Instruction Set Architecture Microarchitecture Digital Logic Devices (transistors, etc.) Hardware Solid-State Physics A Simple Processor 2 Instruction Set Architecture (HW/SW Interface) processor memory Instructions • Names, Encodings Instruction Encoded • Effects Logic Instructions • Arguments, Results Registers Data Local storage • Names, Size • How many Large storage • Addresses, Locations Computer A Simple Processor 3 Computer Microarchitecture (Implementation of ISA) Instruction Fetch and Registers ALU Memory Decode A Simple Processor 4 (HW = Hardware or Hogwarts?) HW ISA An example made-up instruction set architecture Word size = 16 bits • Register size = 16 bits. • ALU computes on 16-bit values. Memory is byte-addressable, accesses full words (byte pairs). 16 registers: R0 - R15 • R0 always holds hardcoded 0 Address Contents • R1 always holds hardcoded 1 0 First instruction, low-order byte • R2 – R15: general purpose 1 First instruction, Instructions are 1 word in size. high-order byte 2 Second instruction, Separate instruction memory. low-order byte Program Counter (PC) register ... ... • holds address of next instruction to execute. A Simple Processor 5 R: Register File M: Data Memory Reg Contents Reg Contents Address Contents R0 0x0000 R8 0x0 – 0x1 R1 0x0001 R9 0x2 – 0x3 R2 R10 0x4 – 0x5 R3 R11 0x6 – 0x7 R4 R12 0x8 – 0x9 R5 R13 0xA – 0xB R6 R14 0xC – 0xD R7 R15 … Program Counter IM: Instruction Memory PC Address Contents 0x0 – 0x1 ß Processor 1. -
The Microarchitecture of the Pentium 4 Processor
The Microarchitecture of the Pentium 4 Processor Glenn Hinton, Desktop Platforms Group, Intel Corp. Dave Sager, Desktop Platforms Group, Intel Corp. Mike Upton, Desktop Platforms Group, Intel Corp. Darrell Boggs, Desktop Platforms Group, Intel Corp. Doug Carmean, Desktop Platforms Group, Intel Corp. Alan Kyker, Desktop Platforms Group, Intel Corp. Patrice Roussel, Desktop Platforms Group, Intel Corp. Index words: Pentium® 4 processor, NetBurst™ microarchitecture, Trace Cache, double-pumped ALU, deep pipelining provides an in-depth examination of the features and ABSTRACT functions of the Intel NetBurst microarchitecture. This paper describes the Intel® NetBurst™ ® The Pentium 4 processor is designed to deliver microarchitecture of Intel’s new flagship Pentium 4 performance across applications where end users can truly processor. This microarchitecture is the basis of a new appreciate and experience its performance. For example, family of processors from Intel starting with the Pentium it allows a much better user experience in areas such as 4 processor. The Pentium 4 processor provides a Internet audio and streaming video, image processing, substantial performance gain for many key application video content creation, speech recognition, 3D areas where the end user can truly appreciate the applications and games, multi-media, and multi-tasking difference. user environments. The Pentium 4 processor enables real- In this paper we describe the main features and functions time MPEG2 video encoding and near real-time MPEG4 of the NetBurst microarchitecture. We present the front- encoding, allowing efficient video editing and video end of the machine, including its new form of instruction conferencing. It delivers world-class performance on 3D cache called the Execution Trace Cache. -
Out-Of-Order Execution & Register Renaming
Asanovic/Devadas Spring 2002 6.823 Out-of-Order Execution & Register Renaming Krste Asanovic Laboratory for Computer Science Massachusetts Institute of Technology Asanovic/Devadas Spring 2002 6.823 Scoreboard for In-order Issue Busy[unit#] : a bit-vector to indicate unit’s availability. (unit = Int, Add, Mult, Div) These bits are hardwired to FU's. WP[reg#] : a bit-vector to record the registers for which writes are pending Issue checks the instruction (opcode dest src1 src2) against the scoreboard (Busy & WP) to dispatch FU available? not Busy[FU#] RAW? WP[src1] or WP[src2] WAR? cannot arise WAW? WP[dest] Asanovic/Devadas Spring 2002 Out-of-Order Dispatch 6.823 ALU Mem IF ID Issue WB Fadd Fmul • Issue stage buffer holds multiple instructions waiting to issue. • Decode adds next instruction to buffer if there is space and the instruction does not cause a WAR or WAW hazard. • Any instruction in buffer whose RAW hazards are satisfied can be dispatched (for now, at most one dispatch per cycle). On a write back (WB), new instructions may get enabled. Asanovic/Devadas Spring 2002 6.823 Out-of-Order Issue: an example latency 1 LD F2, 34(R2) 1 1 2 2 LD F4, 45(R3) long 3 MULTD F6, F4, F2 3 4 3 4 SUBD F8, F2, F2 1 5 5 DIVD F4, F2, F8 4 6 ADDD F10, F6, F4 1 6 In-order: 1 (2,1) . 2 3 4 4 3 5 . 5 6 6 Out-of-order: 1 (2,1) 4 4 . 2 3 . 3 5 . -
Hardware Architecture
Hardware Architecture Components Computing Infrastructure Components Servers Clients LAN & WLAN Internet Connectivity Computation Software Storage Backup Integration is the Key ! Security Data Network Management Computer Today’s Computer Computer Model: Von Neumann Architecture Computer Model Input: keyboard, mouse, scanner, punch cards Processing: CPU executes the computer program Output: monitor, printer, fax machine Storage: hard drive, optical media, diskettes, magnetic tape Von Neumann architecture - Wiki Article (15 min YouTube Video) Components Computer Components Components Computer Components CPU Memory Hard Disk Mother Board CD/DVD Drives Adaptors Power Supply Display Keyboard Mouse Network Interface I/O ports CPU CPU CPU – Central Processing Unit (Microprocessor) consists of three parts: Control Unit • Execute programs/instructions: the machine language • Move data from one memory location to another • Communicate between other parts of a PC Arithmetic Logic Unit • Arithmetic operations: add, subtract, multiply, divide • Logic operations: and, or, xor • Floating point operations: real number manipulation Registers CPU Processor Architecture See How the CPU Works In One Lesson (20 min YouTube Video) CPU CPU CPU speed is influenced by several factors: Chip Manufacturing Technology: nm (2002: 130 nm, 2004: 90nm, 2006: 65 nm, 2008: 45nm, 2010:32nm, Latest is 22nm) Clock speed: Gigahertz (Typical : 2 – 3 GHz, Maximum 5.5 GHz) Front Side Bus: MHz (Typical: 1333MHz , 1666MHz) Word size : 32-bit or 64-bit word sizes Cache: Level 1 (64 KB per core), Level 2 (256 KB per core) caches on die. Now Level 3 (2 MB to 8 MB shared) cache also on die Instruction set size: X86 (CISC), RISC Microarchitecture: CPU Internal Architecture (Ivy Bridge, Haswell) Single Core/Multi Core Multi Threading Hyper Threading vs. -
Dynamic Register Renaming Through Virtual-Physical Registers
Dynamic Register Renaming Through Virtual-Physical Registers † Teresa Monreal [email protected] Antonio González* [email protected] Mateo Valero* [email protected] †† José González [email protected] † Víctor Viñals [email protected] †Departamento de Informática e Ing. de Sistemas. Centro Politécnico Superior - Univ. de Zaragoza, Zaragoza, Spain. *Departament d’ Arquitectura de Computadors. Universitat Politècnica de Catalunya, Barcelona, Spain. ††Departamento de Ingeniería y Tecnología de Computadores. Universidad de Murcia, Murcia, Spain. Abstract Register file access time represents one of the critical delays of current microprocessors, and it is expected to become more critical as future processors increase the instruction window size and the issue width. This paper present a novel dynamic register renaming scheme that delays the allocation of physical registers until a late stage in the pipeline. We show that it can provide important savings in number of physical registers so it can significantly shorter the register file access time. Delaying the allocation of physical registers requires some artifact to keep track of dependences. This is achieved by introducing the concept of virtual-physical registers, which are tags that do not require any storage location. The proposed renaming scheme shortens the average number of cycles that each physical register is allocated, and allows for an early execution of instructions since they can obtain a physical register for its destination earlier than with the conventional scheme. Early execution is especially beneficial for branches and memory operations, since the former can be resolved earlier and the latter can prefetch their data in advance. 1. Introduction Dynamically-scheduled superscalar processors exploit instruction-level parallelism (ILP) by overlapping the execution of instructions in an instruction window.