similar to: [LLVMdev] Let's get rid of neverHasSideEffects

On Aug 21, 2012, at 2:02 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: > All, > > TableGen likes to infer the MCID::UnmodeledSideEffects flag from an instruction's pattern. When an instruction doesn't have a pattern, it is assumed to have side effects. Hi Jakob, I don't understand what you're saying. Are you proposing that all properties (may load,

On Tue, Aug 21, 2012 at 2:02 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk>wrote: > All, > > TableGen likes to infer the MCID::UnmodeledSideEffects flag from an > instruction's pattern. When an instruction doesn't have a pattern, it is > assumed to have side effects. > > It's possible to override this behavior by setting neverHasSideEffects = 1. > > It

On Aug 21, 2012, at 2:02 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: > All, > > TableGen likes to infer the MCID::UnmodeledSideEffects flag from an instruction's pattern. When an instruction doesn't have a pattern, it is assumed to have side effects. > > It's possible to override this behavior by setting neverHasSideEffects = 1. > > It was

On Aug 21, 2012, at 3:02 PM, Chris Lattner <clattner at apple.com> wrote: > > On Aug 21, 2012, at 2:02 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: > >> All, >> >> TableGen likes to infer the MCID::UnmodeledSideEffects flag from an instruction's pattern. When an instruction doesn't have a pattern, it is assumed to have side effects. >

On 08/21/12 16:49, Jim Grosbach wrote: > > I like that. Possibly with the addition that we can filter by a specific property. -Winfer=neverHasSideEffects, e.g., would only show when that specific property is inferred. > > Beyond that, I don't see an alternative to an audit of the instructions that get flagged by such a warning. :( This proposal would certainly make my life easier

On Aug 22, 2012, at 9:40 AM, Evandro Menezes <emenezes at codeaurora.org> wrote: > On 08/21/12 16:49, Jim Grosbach wrote: >> >> I like that. Possibly with the addition that we can filter by a specific property. -Winfer=neverHasSideEffects, e.g., would only show when that specific property is inferred. >> >> Beyond that, I don't see an alternative to an audit

On Aug 21, 2012, at 4:41 PM, Chris Lattner <clattner at apple.com> wrote: > Personally, I don't like the direction of making everything be redundantly specified with "let" clauses and in the patterns. I agree that it is a problem that we're not inferring from Pat<> patterns, and that not all instructions are expressible with patterns, but I'd rather we solve

On Aug 21, 2012, at 3:45 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: >> I don't understand what you're saying. Are you proposing that all properties (may load, store, side effects) be explicitly added to all instructions, and the pattern only be used to produce warnings? > > Yes. > > The side effect inference is worse than the load/store inference, but

On 21 August 2017 at 11:53, Daniel Sanders <daniel_l_sanders at apple.com> wrote: > One thing to be aware of with this is that (IIRC) tablegen uses the pattern to infer things about the pattern. One example I vaguely remember is that an empty pattern would result in the same effect as hasSideEffects=1 and I think there were others. Thanks for the note - excellent point. Looking at

Doh. I missed the list in my first reply... Here's the replay of the conversation: ----- Renato: On 10 August 2015 at 14:05, Krzysztof Parzyszek via llvm-dev <llvm-dev at lists.llvm.org> wrote: > --> %SP<def,tied1> = t2LDMIA_RET %SP<tied0>, pred:8, pred:%CPSR, > %R7<def>, %PC<def>, %SP<imp-use,undef>, %R7<imp-use,undef>, >

Hello, The function ARMBaseInstrInfo::AnalyzeBranch contains the following piece of code: } else if (I->isReturn()) { // Returns can't be analyzed, but we should run cleanup. CantAnalyze = !isPredicated(I); } else { This could lead to cases where for a block that ends with a conditional return, AnalyzeBranch returns false (i.e. analyzed), both TBB and FBB are

in llvm-3.6.2.src 1. when I put this around one of my instruction definitions in my target "InstrInfo.td" file, let TwoOperandAliasConstraint = "$dst = $rs1" in { } I do not see any TIED_TO in the generated GenInstrInfo.inc file for the OperandInfo used by the instruction, the question is what am I doing wrong ? 2. I've noticed that TwoOperandAliasConstraint

Hi, I had (naively?) expected that the instruction to move immediate to register or memory (such as MOV32mi, MOV32ri, MOV64mi32, MOV64ri, MOV64ri32) would be marked with the flag MCID::MovImm via the X86InstrInfo.td (and hence in the generated X86GenInstrInfo.inc). I do not see that to be the case. Can someone please tell me if my expectation is flawed? Is there a better/different way to

I am trying to categorize the machine instructions based on associated static (i.e., as encoded in .td file) machine description and the corresponding APIs. I would like to perform appropriate actions based on the kind of instruction in a tool that I am working on. For example, I'd like to distinguish between memop instructions involving immediate vs register. While it appears that I would be

----- Original Message ----- > From: "Craig Topper" <craig.topper at gmail.com> > To: "Chandler Carruth" <chandlerc at google.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Monday, December 30, 2013 2:29:50 PM > Subject: Re: [LLVMdev] Random question about the x86 backend (and backends in general I suppose)

That flag is specifically used by the foldImmediate optimization in the Peephole pass. We don't implement the TLI foldImmediate hook the peephole pass uses on x86 so we have no reason to set the flag on any instructions What are you trying to do? ~Craig On Fri, Feb 9, 2018 at 11:45 AM, S. Bharadwaj Yadavalli via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Hi, > > I had

On Dec 30, 2013, at 8:40 PM, Chris Lattner <clattner at apple.com> wrote: > > On Dec 30, 2013, at 4:17 PM, Hal Finkel <hfinkel at anl.gov> wrote: > >> ----- Original Message ----- >>> From: "Craig Topper" <craig.topper at gmail.com> >>> To: "Chandler Carruth" <chandlerc at google.com> >>> Cc: "LLVM

0x0f 0x6f 0xc8 And 0x0f 0x7f 0xc1 Should both be movq % mm0, % mm1. (AT&T) However, llvm 3.4 at least does not recognise the second variant as being a valid instruction. We are currently compiling up latest src incase it has been fixed. If not, could someone take a look or recommend how to fix? Lee -------------- next part -------------- An HTML attachment was scrubbed... URL:

I think even if we did use it, MoveImmediate is intended for instructions that move an immediate into a register rather than into memory. It's supposed to indicate instructions that can be folded with the user of the register by changing the user to an immediate instruction. And it wouldn't be set on an instruction like "addl $0, %eax" or "addl $0, (%ecx)" either since

On Jan 7, 2014, at 10:47 AM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote: > > On Jan 7, 2014, at 10:40 AM, Evan Cheng <evan.cheng at apple.com> wrote: > >> >> On Dec 30, 2013, at 8:40 PM, Chris Lattner <clattner at apple.com> wrote: >> >>> >>> On Dec 30, 2013, at 4:17 PM, Hal Finkel <hfinkel at anl.gov> wrote: