similar to: [LLVMdev] LLVM Instruction selection matcher

Is there a generic function that gives the machine instructions and their patterns given in the .td files of a backend specification ? or a subset which match a certain opcode ? otherwise how are the machine instructions being accessed/matched for instruction selection ? -Omer -------------- next part -------------- An HTML attachment was scrubbed... URL:

After enabling assertions and recompilation I still get this error. ~/bin/llvm$ llc -view-isel-dags t3.bc llc: Unknown command line argument '-view-isel-dags'. Try: 'llc -help' llc: Did you mean '-fast-isel-abort'? and I see the view-edge bundles option but get the following error. ~/bin/llvm$ llc -view-edge-bundles t3.bc Writing

On 15/08/11 13:12, محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ wrote: > How do I enable the assertions when building ? > I am using 2.9, the current version, and when I use the standard build llc does > not give me the view-*-dags options. Configure with --enable-assertions Ciao, Duncan. > > -Omer > > On Sat, Aug 13, 2011 at 1:50 AM, Duncan Sands <baldrick at free.fr > <mailto:baldrick at

On 13/08/11 00:01, Cameron Zwarich wrote: > They do work if you have GraphViz binaries in your path when you configure LLVM. I think you also need to build with assertions enabled. Ciao, Duncan. > > Cameron > > On Aug 12, 2011, at 2:59 PM, محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ wrote: > >> I need help with visualizing graphs before and after instruction selection. >> The llc options

How do I enable the assertions when building ? I am using 2.9, the current version, and when I use the standard build llc does not give me the view-*-dags options. -Omer On Sat, Aug 13, 2011 at 1:50 AM, Duncan Sands <baldrick at free.fr> wrote: > On 13/08/11 00:01, Cameron Zwarich wrote: > > They do work if you have GraphViz binaries in your path when you > configure LLVM.

I need help with visualizing graphs before and after instruction selection. The llc options listed in the docs do not work as specified. -Omer 2011/8/8 Rafael Ávila de Espíndola <rafael.espindola at gmail.com> > On 08/06/2011 02:40 AM, Sanjoy Das wrote: > > Hi! > > > > I have a DAG (attached), which, according to me, should result in the > > code for

They do work if you have GraphViz binaries in your path when you configure LLVM. Cameron On Aug 12, 2011, at 2:59 PM, محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ wrote: > I need help with visualizing graphs before and after instruction selection. > The llc options listed in the docs do not work as specified. > > -Omer > > 2011/8/8 Rafael Ávila de Espíndola <rafael.espindola at gmail.com> > On

In llc I can change the selector using -fast-isel. how can I do this in clang ? -Omer -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120411/3efacf9e/attachment.html>

Is the algorithm described in the article "Near-Optimal Instruction Selection on DAGs (https://llvm.org/pubs/2008-CGO-DagISel.html)" really used in llvm instruction selection? I've studied implementation (SelectionDAGISel.cpp) and I see that instructions are selected by target specific MatcherTable generated by llvm-tblgen. In the implementation the first matching pattern from

what do you mean by "more optimal instructions" ? -omer On Wed, Nov 16, 2011 at 1:28 AM, Joe Abbey <jabbey at arxan.com> wrote: > I've done a first pass over the past 6 months of changes and some notable > things stood out: > > * The ARM backend has reworked Set Jump Long Jump EH Lowering. > * The ARM backend includes improved support for Cortex-M > *

I've done a first pass over the past 6 months of changes and some notable things stood out: * The ARM backend has reworked Set Jump Long Jump EH Lowering. * The ARM backend includes improved support for Cortex-M * The ARM backend adds parsing and encoding ARM/Thumb/Thumb2 assembly There are also many many code generation improvements which select more optimal instructions. Those seemed

> Mehdi Amini <mehdi.amini at apple.com> 於 2016年11月30日 上午5:14 寫道： > >> >> On Nov 29, 2016, at 4:02 AM, Bekket McClane via llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: >> >> Hi, >> Though there exists lots of researches on parallelizing or scheduling optimization passes, If you open up the time matrices of

Hi, Though there exists lots of researches on parallelizing or scheduling optimization passes, If you open up the time matrices of codegen(llc -time-passes), you'll find that the most time consuming task is actually instruction selection(40~50% of time) instead of optimization passes(10~0%). That's why we're trying to parallelize the (target-independent) instruction selection process

> On Nov 29, 2016, at 1:14 PM, Mehdi Amini <mehdi.amini at apple.com> wrote: > > >> On Nov 29, 2016, at 4:02 AM, Bekket McClane via llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote: >> >> Hi, >> Though there exists lots of researches on parallelizing or scheduling optimization passes, If you open up the time

Hi Ivan, Matcher table generation which is implemented in utils/DAGISelEmitter.cpp does use heusiristics like number of instructions which a pattern will cover, latency (not the one which Targets scheduling defines) while emitting the candidate patterns for a give dag node. Current implications may not be implication of algorithm in toto though. Thanks, Jatin On Wednesday, March 28, 2018, Ivan

LLVM performs a greedy, bottom-up instruction selection. At each step, it selects the pattern that will absorb the most nodes (roughly: the order can be tweaked by the target using AddedComplexity, which is often used to model the idea that a particular pattern is more profitable than it would otherwise appear). I don’t personally think there is that much to gain from an algorithm significantly

Hi Omer, On Feb 24, 2012, at 8:46 AM, محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ <omerbeg at gmail.com> wrote: > Is there a generic function that gives the machine instructions and their patterns given in the .td files of a backend specification ? > or a subset which match a certain opcode ? I'm not aware of any dump utility functions to display that information concisely. I agree such a thing would be

(readding cc llvmdev) On Feb 24, 2012, at 11:46 AM, محمد ﻋﻤﺮ ﺩﻫﻠﻮﻯ <omerbeg at gmail.com> wrote: > > > otherwise how are the machine instructions being accessed/matched for instruction selection ? > > > > Have a look at the code in SelectionDAGISel. > > > I am looking at the ARM backend. > In specific, the instruction selection. > In Select(N),

Hello. I come back to this older thread. Again, because of i64immSExt32 I receive TableGen error "Could not infer all types in, pattern!" (exact details written below). So far I'm not able to generate selection code with TableGen for the ADD_r* instructions, etc: def i64immSExt32 : PatLeaf<(imm), [{return

Hi there, I try to JIT compile some bitcode and seeing the following error: LLVM ERROR: Cannot select: 0x28ec830: ch,glue = X86ISD::CALL 0x28ec7c0, 0x28ef900, Register:i32 %EDI, Register:i8 %AL, RegisterMask:Untyped, 0x28ec7c0:1 0x28ef900: i32 = X86ISD::Wrapper TargetGlobalAddress:i32<void (i8*, ...)* @_ZN5FooBr7xprintfEPKcz> 0 0x28ec520: i32 = TargetGlobalAddress<void (i8*, ...)*