Arm Community
Site
Search
User
Site
Search
User
Groups
Education Hub
Open Source Software and Platforms
Research Collaboration and Enablement
Forums
AI and ML forum
Architectures and Processors forum
Arm Development Platforms forum
Arm Development Studio forum
Arm Virtual Hardware forum
Automotive forum
Compilers and Libraries forum
Graphics, Gaming, and VR forum
High Performance Computing (HPC) forum
Infrastructure Solutions forum
Internet of Things (IoT) forum
Keil forum
Morello forum
Operating Systems forum
SoC Design and Simulation forum
SystemReady Forum
Blogs
AI and ML blog
Announcements
Architectures and Processors blog
Automotive blog
Graphics, Gaming, and VR blog
High Performance Computing (HPC) blog
Infrastructure Solutions blog
Internet of Things (IoT) blog
Operating Systems blog
SoC Design and Simulation blog
Tools, Software and IDEs blog
Support
Arm Support Services
Documentation
Downloads
Training
Arm Approved program
Arm Design Reviews
Community Help
More
Cancel
Support forums
Arm Development Studio forum
NEON vdiv.f32 syntax
Jump...
Cancel
Locked
Locked
Replies
8 replies
Subscribers
117 subscribers
Views
8792 views
Users
0 members are here
Options
Share
More actions
Cancel
Related
How was your experience today?
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion
NEON vdiv.f32 syntax
Carl van Heezik
over 10 years ago
Note: This was originally posted on 17th April 2012 at
http://forums.arm.com
I am (re)coding a 3D math library with inline NEON assembly for iOS using the Apple LLVM compiler 3.1.
I get an error message on the following instruction:
[color="#000000"] "vdiv.f32 q0, q1, q2 \n\t" [/color]
VFP single or double precision register expected -- `vdiv.f32 q0,q1,q2'
According to the 'Assembler Reference' page 4-76 you should specify a single precision register. The following code works:
[color="#000000"] "vdiv.f32 s0, s4, s8 \n\t" [/color]
"vdiv.f32 s1, s5, s9 \n\t"
"vdiv.f32 s2, s6, s10 \n\t"
I am confused because now the divide is not computed in parallel, which was the reason to use inline assembly.
Also the following instructions work as expected:
[color="#000000"] // component wise add[/color]
[color="#000000"] "vadd.f32 q0, q1, q2 \n\t" [/color]
[color="#008311"] // component wise subtract
[color="#000000"] "vsub.f32 q0, q1, q2 \n\t" [/color]
[color="#008311"] // component wise multiply
[color="#000000"] "vmul.f32 q0, q1, q2 \n\t" [/color][/color][/color]
[color="#000000"]
[color="#ce2f24"][color="#000000"]Why do I get an error message on the vdiv and not on the vadd, vsub and vmul? Is this a compiler error?[/color]
[/color][/color]
Parents
Carl van Heezik
over 10 years ago
Note: This was originally posted on 17th April 2012 at
http://forums.arm.com
Did you had a Acorn Archimedes ?
No I used to program microcontrollers in assembly to control all kinds of machines. Safety software for boilers etc. Those little guys with a minimal amount of ROM / RAM. To clean the program memory you had to give them a UV sunbath. I those days you had to program you own 16 bit multiply and divide etc. I did a good job because they still manufacture thousands of boilers with the majority of the code 15 years old.
Cancel
Up
0
Down
Cancel
Reply
Carl van Heezik
over 10 years ago
Note: This was originally posted on 17th April 2012 at
http://forums.arm.com
Did you had a Acorn Archimedes ?
No I used to program microcontrollers in assembly to control all kinds of machines. Safety software for boilers etc. Those little guys with a minimal amount of ROM / RAM. To clean the program memory you had to give them a UV sunbath. I those days you had to program you own 16 bit multiply and divide etc. I did a good job because they still manufacture thousands of boilers with the majority of the code 15 years old.
Cancel
Up
0
Down
Cancel
Children
No data