Displaying 20 results from an estimated 6000 matches similar to: "[LLVMdev] Non-standard byte sizes"
2011 Jan 28
0
[LLVMdev] Non-standard byte sizes
On Fri, Jan 28, 2011 at 6:29 AM, David Given <dg at cowlark.com> wrote:
> For a hypothetical Evil Project(tm), I would like to do a LLVM backend
> for a virtual machine that does not use 8-bit bytes. Does LLVM support
> this sort of thing?
Not without some modification.
I've developed an LLVM back end for a DSP with 24-bit word-addressable
memory, basically by defining the
2011 Jan 28
2
[LLVMdev] Non-standard byte sizes
On 28/01/11 14:14, Ken Dyck wrote:
[...]
> I've developed an LLVM back end for a DSP with 24-bit word-addressable
> memory, basically by defining the alignment of i8 to be the word size
> of the machine. So it _is_ possible.
I think I might have an easier job of it, as I don't want to use any of
the standard C sizes at all --- my char will be ~64 bits wide (in fact,
my
2010 Sep 02
3
[LLVMdev] Line number information (and other metadata)
I'd like my compiler to emit proper line number information. The docs
talk about Instruction::setDebugLoc(), but that method doesn't actually
have to be in my 2.7 LLVM Debian package. What's the correct way of
doing this?
In addition, can anyone point me at an example of how to emit a comment
attached to an instruction (or function)?
--
┌─── dg@cowlark.com ─────
2010 Sep 22
2
[LLVMdev] Enabling inlining
My language is producing a lot of very short functions, typically two or
three instructions long. These should be ideal candidates for inlining,
but it isn't happening.
My compiler is producing one big bitcode file, and all the functions are
marked as 'internal'. I'm then doing the optimisation and translation
manually using llc -O3 into a .s file, and then linking this against
2010 Aug 23
2
[LLVMdev] Indexing backwards through a structure
Given a structure like this (using C syntax rather than LLVM because I'm
still not fluent with LLVM assembly):
struct Object
{
int i1;
int i2;
int i3;
};
Then, if I have an int* pointer which I know is pointing to the i3
element, what's the best way of recovering a pointer to the structure as
a whole?
My fallback option is to cast the pointer to an int64, use getelementptr
to
2010 Sep 22
0
[LLVMdev] Enabling inlining
On Sep 22, 2010, at 9:54 AM, David Given wrote:
> My language is producing a lot of very short functions, typically two or
> three instructions long. These should be ideal candidates for inlining,
> but it isn't happening.
>
> My compiler is producing one big bitcode file, and all the functions are
> marked as 'internal'. I'm then doing the optimisation and
2010 Sep 08
4
[LLVMdev] Union type, is it really used or necessary?
On 07/09/10 14:22, Erik de Castro Lopo wrote:
[...]
> When generating 32 bit code the struct looks like:
>
> <{ i32, pointer }>
>
> and for 64 bit code:
>
> <{ union { i32, i64 }, pointer }>
Surely LLVM will cause the first structure to be correctly aligned on
64-bit platforms by automatically inserting padding? Is explicit
alignment by the user
2010 Sep 02
3
[LLVMdev] Line number information (and other metadata)
On 02/09/10 18:28, Jim Grosbach wrote:
> On Sep 2, 2010, at 4:05 AM, Renato Golin wrote:
[...]
>> I suggest you getting the SVN code, since quite a lot has changed
>> since last freeze.
>
> Vigourously seconded. It's very true in general, but with regards to debug information in particular, "quite a lot has changed since 2.7" is an understatement. It's an
2013 Jan 20
2
[LLVMdev] On calling intrinsics
On 20/01/13 19:20, Caldarale, Charles R wrote:
[...]
> That's because there is no llvm.ceil.* intrinsic defined in include/llvm/Intrinsics.td for 3.2
Ah. Yes, that would explain it... does this mean that I can rely on all
the intrinsics listed existing for the common types (int, float,
double)? Or should I be trying to follow the libc call route?
I've noticed that llc is successfully
2010 Aug 28
2
[LLVMdev] Dataflow analysis based optimisations
I'm working on an LLVM-based compiler for a very closure-centric
language. It's becoming apparent that it's going to suffer heavily from
garbage collector churn, as all the useful programming idioms the
language makes possible are going to involve memory allocations, either
to create objects or to allocate storage for upvalues.
However, it's possible to optimise away a lot of heap
2014 Mar 19
2
[LLVMdev] Type inference on registers with can contain multiple types
My architecture has an FPU, but uses integer registers to store
floating-point values. So each register can store either an int or an
IEEE float. I define a register class like this:
def GR32 : RegisterClass<"MyArch", [i32, f32], 32,
(sequence "R%u", 0, 32)>;
So far so good. However, when I write a rule to store a register:
def STORE32r : S32<
(outs), (ins
2013 Feb 08
2
[LLVMdev] JIT on armhf
I'm using the Debian LLVM package to try and do JIT on a Linux armhf
device. Unfortunately it seems to be generating armel code rather than
armhf code, and since the ABIs don't match nothing works.
I've tried overriding the triple to arm-unknown-linux-gnueabihf and
arm-linux-gnueabihf (via module->setTargetTriple), and while the triples
are accepted, the actual generated code
2010 Sep 17
6
[LLVMdev] Accurate garbage collection
On 17/09/10 09:55, Pedro Ferreira wrote:
> As I understand it, LLVM simply gives you support for garbage collectors
> that you have to implement yourself and link into the final binary,
> similar to what C's malloc does (it's a library call). The issue with
> GC's is that they need to be provided info about the stack, thats where
> LLVM's support comes in.
Are there
2014 Jul 23
2
[LLVMdev] JIT on armhf, again
Hello,
Last year I tried --- and failed --- to generate float-heavy ARM code
via the JIT on an armhf platform. No matter what I did, it would always
generate armel code instead. This was on LLVM 3.2, which was all that
was available then.
Now I'm running into a requirement to do this again: while it's much
less crashy than it was, I still can't seem to persuade the JIT to
generate
2010 Sep 02
0
[LLVMdev] Line number information (and other metadata)
On 02/09/10 11:27, David Given wrote:
> I'd like my compiler to emit proper line number information. The docs
> talk about Instruction::setDebugLoc(), but that method doesn't actually
> have to be in my 2.7 LLVM Debian package. What's the correct way of
> doing this?
Grr stupid typo.
> The docs
> talk about Instruction::setDebugLoc(), but that method doesn't
2013 Feb 06
2
[LLVMdev] On large vectors
I have a simple expression-evaluation language using LLVM (it's at
https://cowlark.com/calculon, if anyone's interested). It has pretty
primitive support for 3-vectors, which I'm representing as a <3 x float>.
One of my users has asked for proper n-vector support, and I agree with
him so I'm adding that. However, he wants to use quite large vectors.
He's mentioned 30
2011 Jan 25
1
[LLVMdev] LLVM targeting HLLs
On 25/01/11 00:17, David A. Greene wrote:
[...]
> The rewrite is happening. I've got the skeleton of the codegen done,
> but I have to get it to build before I can check it in. After that,
> everyone can start adding patterns.
Is the new C backend 'register' based, that is, generating lots of
little statements operating on lots of variables, rather than producing
the huge
2013 Jan 20
0
[LLVMdev] On calling intrinsics
sqrtf is detected by code in SelectionDAGBuilder.cpp. This gets turns into
a FSQRT ISD node type that the target can handle just like any other ISD
node. If the target doesn't mark ISD::FSQRT as Legal or Custom then
ExpandNode in LegalizeDAG.cpp turns it back into a sqrtf libcall.
On Sun, Jan 20, 2013 at 11:34 AM, David Given <dg at cowlark.com> wrote:
> On 20/01/13 19:20,
2010 Aug 28
2
[LLVMdev] Dataflow analysis based optimisations
On 28/08/10 02:20, Kenneth Uildriks wrote:
> There are passes which mark function parameters as "nocapture", which
> means that the function does not store the passed-in pointer for use
> after that function returns. If pointers to a newly created object
> are only ever passed through "nocapture" parameters, never stored in a
> global, and not returned from the
2010 Aug 28
0
[LLVMdev] Dataflow analysis based optimisations
There are passes which mark function parameters as "nocapture", which
means that the function does not store the passed-in pointer for use
after that function returns. If pointers to a newly created object
are only ever passed through "nocapture" parameters, never stored in a
global, and not returned from the function, then that object is dead
when the function that created