similar to: [LLVMdev] "equivalent" .ll files diverge after optimizations are applied

Using MM registers is wrong unless the user has specifically asked for it, which doesn't seem to be the case here. In the awesome MMX architecture, touching an MM register makes subsequent x87 operations fail unless an EMMS instruction is issued first; none of the compilers here are smart enough to insert EMMS instructions in the right places, so the only safe thing is not to use

Here's the optimized versions: $ opt -std-compile-opts unopt-pass.ll -o - | llvm-dis -o - [...] define %3 @_ZN7WebCore15GraphicsContext19roundToDevicePixelsERKNS_9FloatRectE(%"class.WebCore::GraphicsContext"* %this, %"struct.WebCore::FloatRect"* %rect) nounwind ssp align 2 { %roundedOrigin = alloca %"class.WebCore::FloatSize", align 4 ;

On Aug 31, 2010, at 1:21 PMPDT, Argyrios Kyrtzidis wrote: > > Just to be clear, are you saying that the fact that, after using llc > on the second IR, the produced asm is using MM registers, indicates > a bug ? Yes. It's not immediately obvious whether it's in the opt or llc, though. Chris was doing work involving <2 x float> and may know about this. >

On Jul 31, 2008, at 7:22 AM, Nicolas Capens wrote: > In the same breath I’d also like to kindly ask if someone could have > a look at the reverse operations, namely trunk from 128 to 64 bit > using movdq2q, and 128 to 32 and 64 to 32 using movd. This also > seems related to Bug 2585. Thanks again. The operations you're describing can be represented as insertelement and

Changing the list from cfe-dev to llvm-dev > On 20 Apr 2017, at 4:52 AM, Michael Clark <michaeljclark at mac.com> wrote: > > I’m getting close. I think it may be an issue with an individual intrinsic. I’m looking for the X86 lowering of Instruction::FPToUI. > > I found a comment around the rationale for using a conditional move versus a branch. I believe the predicate logic

Hi all, How do I generate the movq2dq SSE2 instruction using the IRBuilder? There is no zext from 64-bit to 128-bit (corresponding to MMX to XMM register transfer) as far as I can tell. So I've tried inserting an i64 into a v2i64, which generates valid code but rather a number of stores and loads on the stack instead of a single movq2dq. Looking though the code, I found a pattern for

quite some speed improvement indeed. attached the updated patch to apply to svn/trunk. j -------------- next part -------------- A non-text attachment was scrubbed... Name: theora-mmx.patch.gz Type: application/x-gzip Size: 8648 bytes Desc: not available Url : http://lists.xiph.org/pipermail/theora-dev/attachments/20040824/5a5f2731/theora-mmx.patch-0001.bin

Hi Dan, Yes, they could be represented with insertelement and extractelement, but I don't think they actually generate optimal code using movq2dq and such. Else both bugs 2584 and 2585 would be fixed. Anyway, I'm actually already encouraged to get involved myself. I'm quite experienced with MMX and SSE but I'm still trying to learn more about how LLVM does instruction selection

Hi Bill, Comments inline: On 24/10/2011 9:50 PM, Bill Wendling wrote: > On Oct 20, 2011, at 8:42 AM, Nicolas Capens wrote: > >> Hi all, >> >> I'm working on a graphics project which uses LLVM for dynamic code >> generation, and I noticed a major performance regression when upgrading >> from LLVM 2.8 to 3.0-rc1 (LLVM 2.9 didn't support Win64 so I

On Oct 26, 2011, at 1:18 PM, Nicolas Capens wrote: > On 24/10/2011 9:50 PM, Bill Wendling wrote: >> On Oct 20, 2011, at 8:42 AM, Nicolas Capens wrote: >> >>> Hi all, >>> >>> I'm working on a graphics project which uses LLVM for dynamic code >>> generation, and I noticed a major performance regression when upgrading >>> from LLVM

Dear R-help list.I'm not big on programming, but I have a weird error on a couple of packages when trying to install them. I hope someone could help me :-).System: MacBook Pro (1.0) with OS X 10.6.4 R: Installed from web binaries: R version 2.11.1 (2010-05-31) > Sys.getlocale() [1] "en_GB.UTF-8/en_GB.UTF-8/C/C/en_GB.UTF-8/en_GB.UTF-8" I have been trying all day to install the

> This seems like it was done for perf reason (mispredict). Conditional-to-cmov transformation should keep > from introducing additional observable side-effects, and it's clear that whatever did this did not account > for floating point exception. That’s a very reasonable statement, but I’m not sure it corresponds to the way we have typically approached this sort of problem. In

Hello, Here is my first speedup patch. Like 10-11%. No IDCT yet. Please feel free to comment my code or even better think about improvements. :) I belive my routines are not so bad, maybe one day they will be even more faster. What needs to be optimized is the loop filter fuction. I have no ideas now how to do it. It does not leave much space for parallel stuff, copying memory from lot of

On Aug 31, 2010, at 11:18 AM, Argyrios Kyrtzidis wrote: > Hi, > > I've attached 2 .ll files which are supposed to be equivalent but 'unopt-fail.ll' causes a crash in webkit's test suite while 'unopt-pass.ll' does not. I can't give more details about the crash, when I run the crashing test it in isolation it passes, when I run the full suite it crashes; it

hi, i think the current X86 disassembler is quite broken and fails badly on handling REX for x86_64 code. below are some examples: $ echo "0x0f,0xeb,0xc3"|./Release+Asserts/bin/llvm-mc -disassemble -triple=x86_64 .text por %mm3, %mm0 $ echo "0x40,0x0f,0xeb,0xc3"|./Release+Asserts/bin/llvm-mc -disassemble -triple=x86_64 .text por %mm3, %mm0 $ echo

On Wed, Dec 24, 2014 at 2:43 PM, Craig Topper <craig.topper at gmail.com> wrote: > I believe this particular error is caused by this. That seems easy enough > to just drop the bit. Do you have other non-mmx examples? > > case TYPE_MM: \ > if (index > 7) \ > *valid = 0;

On Oct 20, 2011, at 8:42 AM, Nicolas Capens wrote: > Hi all, > > I'm working on a graphics project which uses LLVM for dynamic code > generation, and I noticed a major performance regression when upgrading > from LLVM 2.8 to 3.0-rc1 (LLVM 2.9 didn't support Win64 so I skipped it > entirely). > > I found out that the performance regression is due to removing

Hi all, I'm working on a graphics project which uses LLVM for dynamic code generation, and I noticed a major performance regression when upgrading from LLVM 2.8 to 3.0-rc1 (LLVM 2.9 didn't support Win64 so I skipped it entirely). I found out that the performance regression is due to removing support for lowering 64-bit vector operations to MMX, and using SSE2 instead. My code uses a

Ah , I thought that there is issue while parsing inline asm in function bodies , here are some of instruction where it cribs . Can you make out something of it ? I am going to try out -no-integrated-as option . Not sure if it will help ? *LLVM ERROR: Error parsing inline asm* 1><inline asm>:1:17 : error 0: unexpected token in argument list 1> mov ebx, dword ptr 16(%esp)

On 31-Jul-08, at 2:38 PM, Dan Gohman wrote: > On Jul 31, 2008, at 7:22 AM, Nicolas Capens wrote: >> In the same breath I’d also like to kindly ask if someone could have >> a look at the reverse operations, namely trunk from 128 to 64 bit >> using movdq2q, and 128 to 32 and 64 to 32 using movd. This also >> seems related to Bug 2585. Thanks again. > > The operations