Displaying 20 results from an estimated 70000 matches similar to: "[LLVMdev] constant islands and the first executable instruction of a function"
2013 Nov 19
1
[LLVMdev] possible thumb bug in constant islands
On 11/18/2013 06:34 PM, Jim Grosbach wrote:
> On Nov 18, 2013, at 3:49 PM, reed kotler <rkotler at mips.com> wrote:
>
>> I don't know ARM hardly at all but...
>>
>> This comment does not seem to match the code.
>> Or maybe tBfar is a BL?
> What does the definition of tBfar say?
Okay.. but
// Far jump
// Just a pseudo for a tBL instruction. Needed
2013 Nov 19
0
[LLVMdev] possible thumb bug in constant islands
On Nov 18, 2013, at 3:49 PM, reed kotler <rkotler at mips.com> wrote:
> I don't know ARM hardly at all but...
>
> This comment does not seem to match the code.
> Or maybe tBfar is a BL?
What does the definition of tBfar say?
>
> Also, how does this work if the destination is greater than 2**21?
>
It doesn’t. IIRC, that’s under the category of “if people start
2013 Nov 18
3
[LLVMdev] possible thumb bug in constant islands
I don't know ARM hardly at all but...
This comment does not seem to match the code.
Or maybe tBfar is a BL?
Also, how does this work if the destination is greater than 2**21?
/// fixupUnconditionalBr - Fix up an unconditional branch whose
destination is
/// too far away to fit in its displacement field. If the LR register
has been
/// spilled in the epilogue, then we can use BL to
2013 Oct 11
2
[LLVMdev] where to put the constant island pass?
Currently the ARM port does constant islands on a per function basis.
I'm aware of at least one other port that does this kind of optimization
on the mc layer.
To do such long/short jump and load optimizations, you don't need
anything about registers or basic blocks.
So it seems this would be better because then you can pool things on a
per module basis.
In the case of Mips16, the
2013 Oct 11
0
[LLVMdev] where to put the constant island pass?
ARM absolutely needs to know about control flow in that pass.
-Jim
On Oct 11, 2013, at 2:16 PM, reed kotler <rkotler at mips.com> wrote:
> Currently the ARM port does constant islands on a per function basis.
>
> I'm aware of at least one other port that does this kind of optimization on the mc layer.
>
> To do such long/short jump and load optimizations, you
2013 Feb 17
3
[LLVMdev] keeping instructions in order and hidden dependencies
AFAIK, You have two choices: use a pseudo that is lowered into separate instructions later as part of asm emission, or use MI bundles. The former is generally what existing targets use for this sort of thing, but perhaps the second would work better for you.
Cameron
On Feb 16, 2013, at 8:37 PM, Reed Kotler <rkotler at mips.com> wrote:
> Some of my pseudos do conditional branch .+4 and
2013 Feb 17
4
[LLVMdev] keeping instructions in order and hidden dependencies
You are trying to do a few different things here, and a uniform solution may not work for all of them. For a fixed instruction sequence, e.g. a special kind of move-and-branch sequence used for tail calls, you probably want a pseudo. If you are trying to combine arbitrary instructions together, e.g. Thumb IT blocks, you probably want to use bundles, even if the sequences are a fixed length. I
2013 Feb 17
0
[LLVMdev] keeping instructions in order and hidden dependencies
One of my reasons for lowering things early is that I need to get an
accurate count of the size of things.
Some of the pseudos even have instructions like compare immediate, which
in Mips 16 has two forms depending on the magnitude of the immediate field.
Though I suppose it's possible to leave things as a pseudo and calculate
their size, though I'm not sure where I could store the
2013 Nov 23
2
[LLVMdev] bugpoint question
In that case it tries to do something but fails.
rkotler at ubuntu-rkotler:~/testmips16$
/home/rkotler/llvmw/install/bin/bugpoint casts.bc -llc-safe
--safe-tool-args -target=mips-linux-gnu -mcpu=mips16
-mips16-constant-islands
Read input file : 'casts.bc'
*** All input ok
Initializing execution environment: Found llc:
/home/rkotler/llvmw/install/bin/llc
Running the code
2013 Oct 15
0
[LLVMdev] module level assembly optimization
On Mon, Oct 14, 2013 at 6:56 PM, reed kotler <rkotler at mips.com> wrote:
> I would like to do constant pools over an entire module instead of just on a
> per function basis as constant islands does it now.
>
> It seems there are two options for this:
>
> 1) collect the machine functions with their machine instructions for the
> whole module, edit them as needed and then
2013 Oct 15
5
[LLVMdev] module level assembly optimization
I would like to do constant pools over an entire module instead of just
on a per function basis as constant islands does it now.
It seems there are two options for this:
1) collect the machine functions with their machine instructions for the
whole module, edit them as needed and then
call asmprinter for them one at a time.
2) collect all the instruction streams and store them in lists, one
2013 Nov 23
0
[LLVMdev] bugpoint question
----- Original Message -----
> From: "Reed Kotler" <rkotler at mips.com>
> To: "Hal Finkel" <hfinkel at anl.gov>
> Cc: LLVMdev at cs.uiuc.edu
> Sent: Friday, November 22, 2013 11:18:53 PM
> Subject: Re: bugpoint question
>
> In that case it tries to do something but fails.
>
> rkotler at ubuntu-rkotler:~/testmips16$
>
2013 Feb 25
1
[LLVMdev] constants in text section for mips 16
Why did you take out the constant island code for Arm 64?
Just did not need it?
On 02/21/2013 12:01 PM, Tim Northover wrote:
> Hi Reed,
>
>> I'm wondering if there is already some mechanism where I can assign literals
>> to the text section and get a label for where it has been stored.
>
> I think putting them in the text section is reasonably simple, though
>
2012 Feb 28
0
[LLVMdev] Generate Executable to Mips
Great Job!
If I use alternate-clang-driver, will I need mips-gcc still?
I mean alternate-clang-driver use as&ld directly or by calling gcc?
Regards,
Jia Liu
On Tue, Feb 28, 2012 at 10:39 AM, reed kotler <rkotler at mips.com> wrote:
> There is also:
>
> 1) an alternate clang driver at
> http://code.google.com/p/alternate-clang-driver/ . This makes
> it more or less gcc
2013 Feb 17
0
[LLVMdev] keeping instructions in order and hidden dependencies
Sounds like bundles will be the simplest to start with though I suppose
I could just lower the pseudos after scheduling is done; for now.
Bundles will prevent things from being able to be scheduled in more
creative ways but for that I need to think more about the problem.
So I can just create a bundle, insert instructions in it, and all will
work more or less?
I'm trying to take the next
2013 Nov 23
2
[LLVMdev] bugpoint question
This is my first time using bugpoint. I'm getting the following error:
/home/rkotler/llvmw/install/bin/bugpoint -run-llc casts.bc --tool-args
-target mips-linux-gnu -mcpu=mips16 -mips16-constant-islands
Read input file : 'casts.bc'
*** All input ok
Initializing execution environment: Found llc:
/home/rkotler/llvmw/install/bin/llc
Sorry, I can't automatically select a
2013 Sep 18
2
[LLVMdev] forcing two instructions to be together
I used the A9 schedule as an example:
http://llvm.org/svn/llvm-project/llvm/trunk/lib/Target/ARM/ARMScheduleA9.td
The documentation could use more clarity, but this is how I was able to do it to always get two specific instructions to be scheduled together.
________________________________________
From: reed kotler [rkotler at mips.com]
Sent: Tuesday, September 17, 2013 8:54 PM
To: Micah Villmow
2013 Sep 18
0
[LLVMdev] forcing two instructions to be together
That doesn't actually give you a guarantee that they won't be split up. Phases other than the scheduler may insert instructions in the middle of block (constant island pass, for example). Pseudo-instructions are the canonical answer to that problem.
--Owen
On Sep 17, 2013, at 11:09 PM, Micah Villmow <micah.villmow at smachines.com> wrote:
> I used the A9 schedule as an
2012 Feb 28
3
[LLVMdev] Generate Executable to Mips
There is also:
1) an alternate clang driver at
http://code.google.com/p/alternate-clang-driver/ . This makes
it more or less gcc compatible.
2) there is a way to invoke it all directly with just a call to clang as
is with x86/linux but it's not totally
finished. i will try and post something about this. the direct form will
work if you are on a
mips linux machine but there are still some
2013 Nov 23
0
[LLVMdev] bugpoint question
----- Original Message -----
> From: "reed kotler" <rkotler at mips.com>
> To: LLVMdev at cs.uiuc.edu
> Sent: Friday, November 22, 2013 8:40:24 PM
> Subject: [LLVMdev] bugpoint question
>
> This is my first time using bugpoint. I'm getting the following
> error:
>
> /home/rkotler/llvmw/install/bin/bugpoint -run-llc casts.bc
> --tool-args
>