similar to: [LLVMdev] qualitative comparison of correctness of llvm and gcc

Hi John, > A "volatile error" indicates a case where a compiler failed to respect > the volatile invariant. The volatile invariant is simply that changing > the optimization level of a strictly conforming C program must not > change the number of dynamic loads or stores to any variable that is > volatile-qualified in the compiler's input. We check this with a hacked

Hi Duncan- > does this also check that writes are atomic: that they are performed in > one processor operation? Can you elaborate a bit? I don't think volatile has any atomicity requirements. Of course I can make a struct, an int128_t, or whatever volatile (on AVR even an int16_t is updated non-atomically!). Lack of atomicity is one of many problems with using volatile as a basis

Hi John, > > does this also check that writes are atomic: that they are performed in > > one processor operation? > > Can you elaborate a bit? I don't think volatile has any atomicity > requirements. Of course I can make a struct, an int128_t, or whatever > volatile (on AVR even an int16_t is updated non-atomically!). that's not entirely true in practice: if

Hi all, I did a performance test of two real applications (FFMPEG and GTK) on ARM. For more details see: http://laurovenancio.wordpress.com/2007/08/07/llvm-perf-tests/ Lauro

Hi Lauro, On 14 Aug 2007, at 01:10, Lauro Ramos Venancio wrote: > Hi all, > > I did a performance test of two real applications (FFMPEG and GTK) on > ARM. For more details see: > http://laurovenancio.wordpress.com/2007/08/07/llvm-perf-tests/ Could you give me some more information about the applications you compiled and ran? Where can I obtain source codes, which input did

On 31 Aug 2006, at 19:13, Chris Lattner wrote: > On Thu, 31 Aug 2006, Kenneth Hoste wrote: > >> When I adjust the settings in Makefile.nagfortran as follows, I'm >> able to get bytecode file for lucas, galgel and facerec, but make >> still quits with an error (after generating >> bytecode files for 7 (out of 26) benchmarks. >> >> Also, the file

On Thu, 31 Aug 2006, Kenneth Hoste wrote: > Bummer. I think I'll contact the NAG support for more info on this. Can you > show me the content of your Makefile.nagfortran? It is identical to yours. > Also, it is possible to tell make only to compile benchmark X? How can I > enforce this? Go into the directory for that benchmark, then run 'make' or whatever. -Chris --

Hi Dylan, the following code volatile uint8_t v1; volatile uint8_t v2; __attribute__((interrupt)) void __vector_21(void) { v2 = v1; } produces in C mode: 00000092 <__vector_21>: 92: 80 91 61 00 lds r24, 0x0061 ; 0x800061 <v1> 96: 80 93 60 00 sts 0x0060, r24 ; 0x800060 <__data_end> 9a: 08 95 ret and in C++ mode: 00000074

Hi, I noticed that LLVM had signed up as a mentoring organization for Google's summer of code. LLVM looks like an exciting project that overlaps some of my interests. I would be interested in developing an additional front end for a language it does not currently support (I'm open to what language). I do not know much about what this entails in regards to what LLVM requires from its

Am 04.03.20 um 13:28 schrieb Dylan McKay: > > * *The C/C++ function needs to be declared with either the calling > convention avr-interrupt or avr-non-blocking-interrupt.* Skipping > this step will cause regular ret instructions to be emitted for > return-from-subroutine, instead of the required reti for interrupt > handlers. ISRs also have stricter

Hey Wilhelm, Could you post the LLVM IR generated from your C++ file? This can be achieved with 'clang -S -emit-llvm' Cheers On Sat, Mar 28, 2020 at 6:36 PM Wilhelm Meier <wilhelm.meier at hs-kl.de> wrote: > Answering partly to myself there was a extern "C" missing. > > But the register pushes ans reti are still missing. > > Whats wrong? > > Am

Hey Wilhelm, That's a bug, the "interrupt" attribute is not being recognized by the backend. I have fixed it in https://github.com/llvm/llvm-project/commit/339b34266c1b54a9b5ff2f83cfb1da9cd8c9d90a Pull the latest LLVM and it should be fixed. On Tue, Mar 31, 2020 at 8:00 AM Wilhelm Meier <wilhelm.meier at hs-kl.de> wrote: > Hi Dylan, > > I used the following

On 31 Aug 2006, at 23:46, Chris Lattner wrote: > On Thu, 31 Aug 2006, Kenneth Hoste wrote: >> Bummer. I think I'll contact the NAG support for more info on >> this. Can you >> show me the content of your Makefile.nagfortran? > > It is identical to yours. > >> Also, it is possible to tell make only to compile benchmark X? How >> can I >>

Hi Scott, On 18 Mar 2007, at 04:22, Scott Fortmann-Roe wrote: > Hi, > > I noticed that LLVM had signed up as a mentoring organization for > Google's summer of code. LLVM looks like an exciting project that > overlaps some of my interests. > > I would be interested in developing an additional front end for a > language it does not currently support (I'm open to

I have been wondering why llvm-ld generates the same code with or without the option "-O5" so I looked at its source (llvm 2.2). And apparently, the options "-On" are accepted but never used! The program runs a fixed set of optimization passes, unless "-disable-opt" is specified. What is the reason for this? If this is intended, then the documentation should say

On Thu, 17 Apr 2008, HyperQuantum wrote: > I have been wondering why llvm-ld generates the same code with or without the option "-O5" so I looked at its source (llvm 2.2). And apparently, the options "-On" are accepted but never used! The program runs a fixed set of optimization passes, unless "-disable-opt" is specified. What is the reason for this? If this is

Is there anything I can do about it? BTW: gcc is loosing the AVR backend, so I would assume, there will be a greater interest to this in llvm compared to the past. Thanks, Wilhelm Am 03.04.20 um 15:09 schrieb Wilhelm Meier via llvm-dev: > Should I create an issue in bugzilla for this? Just to be reminded ... > > Am 31.03.20 um 09:34 schrieb Wilhelm Meier via llvm-dev: >> Hi

Hi Dylan, looks ok now. One thing: the ISR is now: __vector_21: ; @__vector_21 __vector_21$local: sei push r0 push r1 in r0, 63 push r0 clr r0 push r24 lds r24, v1 sts v2, r24 pop r24 pop r0 out 63, r0 pop r1 pop r0 reti There are unneccessary push/pops of r1 and r0 too, since the clr is useless ... GCC had the same

Thank you for both of your input. Yes, I try to cross-compile for AVR, the simple ATMEGA328P used in every Arduino Uno. My main motivation being that I hope to be able to use a couple of STL containers, <functional> and <type_traits> on the MCU. Not sure though if this can be reached by going via the clang route. Getting back to the compilation: when I run clang with both both

Hi Everyone, I set up a page to host the videos and slides from the meeting, and uploaded all the videos: http://llvm.org/devmtg/2007-05/index.html So far, I only have one set of slides on the page - please send me your slides! :) Also, I'd appreciate it if someone would write a blurb describing an overview of the meeting, etc at the top. Also, Scott, please let me know when it's ok