What exactly is the difference between SIMD (Single Instruction Multiple Data) and VLIW (Very Long Instruction Word)? Is one a subset of the other? Or are they two completely difference things?
Are SIMD and VLIW instructions the same thing?
2.2k Views Asked by Izzo At
1
There are 1 best solutions below
Related Questions in X86
- Why do we need AX instead of MOV DS, data directly with a segment?
- Drawing circles of increasing radius
- Assembly print on screen using pop ecx
- How to add values from vector to each other
- Intel x64 instructions CMPSB/CMPSW/CMPSD/CMPSQ
- Compact implementation of logical AND in x86 assembly
- Can feenableexcept hurt a program performance?
- How do I display the result and remainder in ax and dx in Assembly (tasm)
- ASM : Trouble using int21h on real machine
- jmp instruction *%eax
- What steps are needed to load a second stage bootloader by name on a FAT32 file system in x86 Assembly?
- Assembly code to print a new line string
- Write System Call Argument Registers
- How to jump to an address saved in a register in intel assembly?
- Find middle value of a list
Related Questions in CPU-ARCHITECTURE
- Real-world analog to TIS-100
- What is faster: equal check or sign check
- Multicore clock counter consistency
- How do MemReq and MemResp exactly work in RoccIO - RISCV
- What is the simplest Turing complete CPU instruction set which can execute code from ROM?
- Had 16-bit DOS a memory access limitation of 1 MB? If yes, how?
- Are correct branch predictions free?
- Assembly: why some x86 opcodes are invalid in x64?
- Memory barriers force cache coherency?
- FreeRTOS : How to measure context switching time?
- HACK Machines and its assembler
- Peak FLOPs per cycle for ARM11 and Cortex-A7 cores in Raspberry Pi 1 and 2
- Computer Architecture/Assembly, Amdahl's Law
- How the heap and stack size is decided in process image
- How can I get the virtual address of a shared library by the use of computer architecture state?
Related Questions in SIMD
- OpenMP SIMD on Power8
- How to add values from vector to each other
- Effective way to extract from SSE vector on AMD processors
- Running Yeppp library with Mono on Raspbery Pi
- Store, modify and retrieve strings with GCC Vector Extensions?
- parallelizing matrix multiplication through threading and SIMD
- SSE - AVX conversion from double to char
- 32-bit Hamming String formation from 32 8-bit comparisons
- Optimizing SIMD histogram calculation
- Initializing int4 using Swift; bug or expected behaviour?
- Vectorize 2d-array access (GCC)
- Is it really efficient to use Karatsuba algorithm in 64-bit x 64-bit multiplication?
- (Vec4 x Mat4x4) product using SIMD and improvements
- What are some rules of thumb for when SIMD would be faster? (SSE2, AVX)
- How can I use simd in MIPS?
Related Questions in INSTRUCTION-SET
- Real-world analog to TIS-100
- What is the simplest Turing complete CPU instruction set which can execute code from ROM?
- How can I get the number of instructions executed by a program?
- Can't Compile for MIPS or ATOM with gcc
- Factors in designing Instruction set Arcitecture
- Transpiling to C vs C++ : range of CPU instructions
- Instruction execution latencies for A53
- Understanding FMA instructions performance
- Questions about adding jal instruction to mips single cycle datapath
- opcode of transfer from memory to register
- Instruction Encoding relating to MARIE Assembly language
- What instruction set does the Nvidia GeForce 6xx Series use?
- Clang vs gcc floating point performance on ARM
- MSP430 SWAP bytes explanation assembly
- Where is an ISA stored and how exactly is it taken into account?
Related Questions in VLIW
- Reorder Buffer in Speculative Execution always needed?
- How ALU execute instruction in AMD GPU (VLIW)?
- VLIW - Instructon width performance increase
- Power efficient and Speed efficient architecture for Multimedia Applications
- superscalar and VLIW
- Are SIMD and VLIW instructions the same thing?
- Why are name dependencies (WaR, WaW) in ILP architectures problematic?
- What's the advantage of compiler instruction scheduling compared to dynamic scheduling?
- very long instruction that consists of operations with different latencies
- Opencl and HD5850
- Instruction Level Parallelism (ILP) Methods
- LLVM compiler infrastructure for VLIW architectures
- GCC compiler infrastructure for VLIW architectures
Trending Questions
- UIImageView Frame Doesn't Reflect Constraints
- Is it possible to use adb commands to click on a view by finding its ID?
- How to create a new web character symbol recognizable by html/javascript?
- Why isn't my CSS3 animation smooth in Google Chrome (but very smooth on other browsers)?
- Heap Gives Page Fault
- Connect ffmpeg to Visual Studio 2008
- Both Object- and ValueAnimator jumps when Duration is set above API LvL 24
- How to avoid default initialization of objects in std::vector?
- second argument of the command line arguments in a format other than char** argv or char* argv[]
- How to improve efficiency of algorithm which generates next lexicographic permutation?
- Navigating to the another actvity app getting crash in android
- How to read the particular message format in android and store in sqlite database?
- Resetting inventory status after order is cancelled
- Efficiently compute powers of X in SSE/AVX
- Insert into an external database using ajax and php : POST 500 (Internal Server Error)
Popular Questions
- How do I undo the most recent local commits in Git?
- How can I remove a specific item from an array in JavaScript?
- How do I delete a Git branch locally and remotely?
- Find all files containing a specific text (string) on Linux?
- How do I revert a Git repository to a previous commit?
- How do I create an HTML button that acts like a link?
- How do I check out a remote Git branch?
- How do I force "git pull" to overwrite local files?
- How do I list all files of a directory?
- How to check whether a string contains a substring in JavaScript?
- How do I redirect to another webpage?
- How can I iterate over rows in a Pandas DataFrame?
- How do I convert a String to an int in Java?
- Does Python have a string 'contains' substring method?
- How do I check if a string contains a specific word?
Completely unrelated, and orthogonal. A machine can have one or both, or neither. SIMD instructions could be added to a VLIW ISA as an extension. (But VLIW is baked in to the machine-code format and ISA.)
VLIW is multiple instructions in one block to be decoded together, and executed without checking for hazards / dependencies between them: the compiler is required to do that, so the VLIW idea is to offload some of that work of finding instruction-level parallelism (ILP) to the compiler.
One of the most well-known examples is Intel/HP's Itanium ISA. https://www.realworldtech.com/mckinley/ covers some details about it, and the first-gen Merced microarchitecture (which wasn't very good). https://www.realworldtech.com/ev8-mckinley/5/ has more details about the 2nd-gen microarchitecture, McKinley.
VLIW is one way to provide some MIMD capability (multiple instructions on multiple data, doing different things to different data.)
SIMD is one instruction doing the same thing to multiple elements of data, so getting more work per clock through the CPU pipeline only involves widening the execution units, not the whole pipeline. (Single Instruction, Multiple Data.) A problem with lots of data parallelism can expose that to the CPU in the form of SIMD, ILP, and thread-level parallelism, all at the same time.
(e.g. a matrix multiply or dot product which uses multiple accumulators to create separate dependency chains (ILP), where each accumulator is a vector of 4, 8, or 16 floats (SIMD). And you can divide that work up across cores, so you can get e.g. 2x 8 FMAs per clock per core on Skylake or Zen2.)