similar to: [RFC] Injecting new element atomic memory intrinsics into MemIntrinsic class hierarchy

Hi Sanjoy, Response/thoughts below... On Aug 19, 2017, at 3:13 PM, Sanjoy Das <sanjoy at playingwithpointers.com<mailto:sanjoy at playingwithpointers.com>> wrote: Hi Daniel, On Thu, Aug 17, 2017 at 8:32 AM, Daniel Neilson via llvm-dev <llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote: Cons: One more attribute to check when implementing a pass that

Hi All, In the language reference manual, the access behavior of the memcpy, memmove and memset intrinsics is not well defined with respect to the volatile flag. The LRM even states that "it is unwise to depend on it". This forces optimization passes to be conservatively correct and prevent optimizations. A very simple example of this is : $ cat test.c #include <stdint.h>

Same patches as before, but 0002-memcpy has been updated to put the (is|set)SrcVolatile methods to where they logically belong : MemTransferInst. This makes (is|set)Volatile methods look a bit ugly to keep compatibility with existing behaviour, but they will hopefully disappear when all users have moved to the new interface --- in the next series of patches. I plan to give a try to phabricator

Hi, all. I have noticed that LLVM supports some Intrinsic Functions such as *"** llvm.sadd.with.overflow"* described in http://llvm.org/docs/LangRef.html#int_sadd_overflow. We can use these functions and needn't define the function bodies. For example, I can manually insert codes: * %res = call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b) %sum = extractvalue

Hi all, I have this problem: I'm using LLVM's C++ API, mostly `IRBuilder<>` to generate code. Some of the generated code is just storing constant data to a location provided as a function argument. Something like `ir_builder.CreateStore(get_default_data(), ptrValue)` where `get_default_data()` may return a `ConstantArray` of `i8` and `ptrValue` is a function argument. Looking

On Fri, Oct 22, 2004 at 03:18:00PM +0200, Marc Ordinas i Llopis wrote: > I'm currently looking at LLVM as a possible back-end to a dynamic > programming system (in the tradition of Smalltalk) we are developing. Neat! > I have read most of the llvmdev archives, and I'm aware that some > things are 'planned' but not implemented yet. We are willing to > contribute

Sarah Thompson wrote: > ... can *any* instruction(s) other than load and store cause memory > reads or writes? Not that I know of, but some intrinsic functions do. > > This is pretty important, because I need to be able to track (at least) > writes, and ideally also reads in order to be able to make > explicit-state model checking work efficiently. I specifically know that

... can *any* instruction(s) other than load and store cause memory reads or writes? This is pretty important, because I need to be able to track (at least) writes, and ideally also reads in order to be able to make explicit-state model checking work efficiently. (I don't really care about reads or writes to spilled registers added by the code generator). Sarah

I can't think of a better way to do this, so I think it's ok. I also submitted a complementary patch on llvm-commits clarifying volatile semantics. -Andy On Jan 28, 2013, at 8:54 AM, Arnaud A. de Grandmaison <arnaud.allarddegrandmaison at parrot.com> wrote: > Hi All, > > In the language reference manual, the access behavior of the memcpy, > memmove and memset

I think this is the same underlying issue as https://bugs.llvm.org/show_bug.cgi?id=40320. CCing Reid, who's had a bunch of thoughts on this in the past. On 1/11/20, 10:25 AM, "llvm-dev on behalf of Chrulski, Christopher M via llvm-dev" <llvm-dev-bounces at lists.llvm.org on behalf of llvm-dev at lists.llvm.org> wrote: Hi, I've run into a bug with the LLVM

I think the simplest, most complete, short term fix, would be to call llvm::colorEHFunclets, and to have the relevant instrumentation passes apply the appropriate funclet bundle when inserting function calls. It's not elegant because it means every simple instrumentation pass that inserts regular function calls (ASan, TSan, MSan, instrprof, etc) needs to be funclet-aware. But, it will work,

Hi everybody, I'm currently looking at LLVM as a possible back-end to a dynamic programming system (in the tradition of Smalltalk) we are developing. I have read most of the llvmdev archives, and I'm aware that some things are 'planned' but not implemented yet. We are willing to contribute the code we'll need for our project, but before I can start coding I'll have to

On Sat, 23 Oct 2004, Misha Brukman wrote: > > A possible view of intrinsics could be "operations that don't depend > > on the target architecture, but instead on the language runtime". But > > then wouldn't malloc/free be intrinsics? > > Good question. Due to the amount of pointer/data analysis in LLVM, it > is often necessary to consider memory

FWIW, +1 from me. Just one request on the implementation though. However we model these intrinsics and their properties (metadata, constants, etc), can we please abstract away those details the same way we have MemCpyInst which just wraps an IntrinsicInst? I think this would be very beneficial if we ever need to add more state, or change something about the underlying implementation, and not

Thanks Andy and Chandler, After specifying the volatile access behaviour, the second step was to autoupgrade the memmove/memcpy intrinsics, and implement (is|set)Volatile in terms of (is|set)(Src|Dest)Volatile, with no functional change. 0001-Specify-the-access-behaviour-of-the-memcpy-memmove-a.patch is the one you already reviewed, unaltered.

Greetings all, I am picking up the work that was started in https://reviews.llvm.org/D27133 — adding support for an element-atomic memcpy/memset/memmove to LLVM. I would appreciate suggestions/thoughts/advice/comments on how to best proceed with this work in a way that will be acceptable to the LLVM group. I apologize in advance; this is going to be a long one... **Background** Loads/stores

Hello all, I am a LLVM newer who want to add a new backend(EBC) into LLVM. After coping the related files from another target and modifying it, I meet a problem when I build the project. The error message is as follows: ================================================================ [ 94%] Built target llvm-dis Linking CXX executable ../../bin/llvm-mc Undefined symbols:

----- Original Message ----- > From: "Chandler Carruth" <chandlerc at gmail.com> > To: "Hal Finkel" <hfinkel at anl.gov>, "Chandler Carruth" <chandlerc at gmail.com> > Cc: "llvm-dev" <llvm-dev at lists.llvm.org> > Sent: Friday, February 5, 2016 4:36:54 PM > Subject: Re: [llvm-dev] [RFC] FP Environment and Rounding mode

Hi Hal, > If you attach noalias metadata to the memcpy call, it will apply to both the source and destination; we don't have a way to differentiate. It might be true that if you attach both noalias and alias.scope metadata to the call, then querying the call against itself will return NoModRef, but that's really hacky (and, in part, wrong, because the destination still alias with

Hello all, I am a LLVM newer who want to add a new backend(EBC) into LLVM. After coping the related files from another target and modifying it, I meet a problem when I build the project. The error message is as follows: ================================================================ [ 94%] Built target llvm-dis Linking CXX executable ../../bin/llvm-mc Undefined symbols: