Boost Performance Optimizations. Rafael Taubinger Sr. FAE

Transcription

1 Boost Performance Optimizations Rafael Taubinger Sr. FAE

2 Agenda Company Overview Company The Compiler Overview The Reasons Compiler to Optimize Reasons Structure to your Optimize application to boost optimization Structure your application to boost Optimization settings optimization Demo Optimization settings Questions Demo Questions

3 Providing developers of embedded systems with world-leading software tools Global professional technical support in 9 languages Large ecosystem of partners 10 offices worldwide with HQ in Uppsala, Sweden Uppsala Munich Paris Tokyo Seoul Shanghai San Francisco Dallas Boston Los Angeles + Distributor representation in 43 countries Listed on NASDAQ/ Stockholm 33 years in the industry 32% of revenue invested in R&D

4 Complete offering for ARM Cortex-A15 Cortex-A9 Cortex-A8 Cortex-A7 Cortex-A5 Cortex-R7 Cortex-R5 Cortex-R4 Cortex-M7 Cortex-M4 Cortex-M3 Cortex-M1 Cortex-M0(+) ARM11 ARM9 ARM7 SecurCore Unique independence with support for all available ARM cores, from all major vendors including TI, Renesas, NXP, ST, Cypress, Toshiba etc. 4,500+ supported devices in total 8,400+ example projects to enable quick start Close cooperation with several SoC vendors Take full control of your development! C-STAT: Powerful static code analysis C-RUN: Runtime execution analysis I-jet and I-jet Trace: Debugging and trace probes

5 The Compiler

6 The Compiler System User Code C Source C Source C Source Compiler System Object File Compiler Object File Object File OS Other Lib Third-Party Code C Library Linker Executable Hardware

7 Optimizations x = x C Source 15 Parser Intermediate Code LDR R0,x LDR R1,[R0,#0] SUB R1,#15 STR R1,[R0,#0] x = x - 15; COMPILER Code Generator High-Level Optimizer Target Code Assembler Function inlining Object Code Dead code elimination Loop unrolling Low-Level Optimizer Crosscall Scheduling Peephole

8 Reasons to Optimize

9 Why optimize? Keep up with connected devices Use a device cheaper smaller with less device memory Room for more features Faster execution Enhance battery life Save power Better response time

10 Traditional Tradeoff Room for more features Use a cheaper device Use a device with less memory Size vs Speed Power Saving power Enhance battery time Better response time Faster execution

11 Size vs Speed Cross Call Elimination vs Function Inlining

12 The Golden Goal

13 The golden goal As fast as possible, but smaller than X

14 Bad idea because: 1. The compiler doesn t know your application

15 A Hypothetical Embedded Application Setup Sleep Data input Calculation Data output External event

16 Bad idea because: 1. The compiler doesn t know about your application 2. Adding or changing code will introduce performance changes in unrelated code

17 A Hypothetical Embedded Application Setup Sleep Data input Filter Calculation Data output External event

18 The Solution

19 Structuring the application To be efficient and portable Isolate device-dependent code Use tuned code where needed Optimize the rest for size Speed Optimization Size Optimization Generic code Speed sensitive code Device Driver Files Hardware

20 Four levels to apply optimizations 1. Project 2. File group 3. File 4. Function #pragma optimize=none void delay(int time) {... }

21 Demo

22 Tips to help the compiler Give more information Avoid global variables Use static to restrict visibility Use Multi file compile (--mfc) to increase code volume

23 Tips to help the compiler Use efficient data types double > float > signed int > unsigned int What about: char, long, short?

24 More types Just because an integer type is smaller, it is not necessarily more efficient ARM: int is more efficient than a char Solution: Use typedefs from <stdint.h> Fastest possible with at least X bits: fast_uint8_t fast_int32_t fast_uint16_t Exactly X bits: uint32_t int64_t uint8_t

25 Power debugging Tune the application to minimize power-consuming use of hardware resources Enabled by I-jet or other hardware with power debugging support Integrated measuring of power consumption correlated to the source code Power breakpoints Detailed power logs Function-level power profiling

26 Questions?

27 Thank you for your attention!