search for: inc8r

I have a question: In the pattern below from X86 def INC8r : I<0xFE, MRM0r, (outs GR8 :$dst), (ins GR8 :$src), "inc{b}\tdst", [(set GR8:$dst, (add GR8:$src, 1))]>; Since we are emitting only "inc $dst", What makes sure that the $src and $dst are same register? - Sanjiv

sanjiv gupta wrote: > I have a question: > In the pattern below from X86 > > def INC8r : I<0xFE, MRM0r, (outs GR8 :$dst), (ins GR8 :$src), > "inc{b}\tdst", > [(set GR8:$dst, (add GR8:$src, 1))]>; > > Since we are emitting only "inc $dst", > What makes sure that the $src and $dst are same register? > > - Sanjiv It's enclosed i...

On Tue, 2008-09-23 at 13:33 +0100, Richard Osborne wrote: > sanjiv gupta wrote: > > I have a question: > > In the pattern below from X86 > > > > def INC8r : I<0xFE, MRM0r, (outs GR8 :$dst), (ins GR8 :$src), > > "inc{b}\tdst", > > [(set GR8:$dst, (add GR8:$src, 1))]>; > > > > Since we are emitting only "inc $dst", > > What makes sure that the $src and $dst are same register? > > &gt...

I have some instructions that use a register as both an input and as the output. Is there a way to specify this constraint in the InstrInfo.td or will this have to be custom selected/lowered? Thanks -- Christopher Lamb christopher.lamb at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL:

I see in the x86 InstInfo.td the following for the INC instructions: def INC8r : I<0xFE, MRM0r, (ops GR8 :$dst, GR8 :$src), "inc{b} $dst", [(set GR8:$dst, (add GR8:$src, 1))]>; Which seem to have the same restriction that I'm trying to implement, but I don't understand how this ensures that $src and $dst are the same register. --...

On Thu, 1 Mar 2007, Christopher Lamb wrote: > I see in the x86 InstInfo.td the following for the INC instructions: > > def INC8r : I<0xFE, MRM0r, (ops GR8 :$dst, GR8 :$src), "inc{b} $dst", > [(set GR8:$dst, (add GR8:$src, 1))]>; > > Which seem to have the same restriction that I'm trying to implement, > but I don't understand how this ensures that $src and $dst are the >...

I found that LLVM were using Binutils to assemble the Assembly Code to the Machine Code, so I have a question, why LLVM don't direct generate the machine code? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20080923/b7e42591/attachment.html>

On Sep 22, 2008, at 13:36, 罗勇刚 wrote: > I found that LLVM were using Binutils to assemble the Assembly Code > to the Machine Code, so I have a question, why LLVM don't direct > generate the machine code? There was a protracted and rather uninteresting discussion of this matter on this list some months ago. I'll summarize the outcome of that thread briefly: LLVM does

sanjiv gupta wrote: > On Tue, 2008-09-23 at 13:33 +0100, Richard Osborne wrote: > >> sanjiv gupta wrote: >> >>> I have a question: >>> In the pattern below from X86 >>> >>> def INC8r : I<0xFE, MRM0r, (outs GR8 :$dst), (ins GR8 :$src), >>> "inc{b}\tdst", >>> [(set GR8:$dst, (add GR8:$src, 1))]>; >>> >>> Since we are emitting only "inc $dst", >>> What makes sure that the $src and $dst are same register...

Hi, Is it possible to define an Instruction with tablegen that reads and writes the same register? For example, an increment instruction that reads a value from a register, adds one to it and then writes the result back to the same register. Thanks, Tom

...to make up an opcode. > > ~Craig > > On Fri, Jul 7, 2017 at 10:43 PM, hameeza ahmed <hahmed2305 at gmail.com> > wrote: > >> Thank You. >> >> Now i am getting this error repeatedly; >> >> Error: Primary decode conflict: VADD_256B would overwrite INC8r >> ModRM 192 >> Opcode 254 >> Context IC >> Error: Primary decode conflict: VADD_256B would overwrite INC8r >> ModRM 193 >> Opcode 254 >> Context IC >> >> Is it due to opcode conflict? what should i keep opcode then? >> >> >...