similar to: [LLVMdev] Optimization pass reference/guide?

Displaying 20 results from an estimated 9000 matches similar to: "[LLVMdev] Optimization pass reference/guide?"

2013 Jan 06
0
[LLVMdev] Optimization pass reference/guide?
Hi, On 06/01/13 16:48, edA-qa mort-ora-y wrote: > Is there some kind of guide to the various optimization passes? I see > their names in the class list, and the various "createXXX" functions, > but I'm not sure if there are ordering requirements or perhaps unsafe > optimizations. there are no ordering requirements, in the sense that all passes are supposed to work
2013 Jan 06
1
[LLVMdev] Optimization pass reference/guide?
On 06/01/13 17:09, Duncan Sands wrote: > should never do any incorrect transformations no matter what order they > are run in. However several passes only do something useful if some > other pass has been run first, for example most passes need to be run > after mem2reg or sroa in order to be effective. > > See also http://llvm.org/docs/Passes.html How can I get from a name of
2013 Nov 08
2
[LLVMdev] UNREACHABLE executed at MCJIT.cpp:322!
That makes it more mysterious then since I am indeed only calling a main function. Perhaps I have to invoke it a different way. Here's my call I have now: auto main = linker->getModule()->getFunction( "main" ); std::vector<llvm::GenericValue> args(2); args[0].IntVal = llvm::APInt( platform::abi_int_size, 0 ); args[1].PointerVal = nullptr; llvm::GenericValue gv =
2012 Nov 11
4
[LLVMdev] IR sizeof?
Is there a way to get the size of a type in the IR assembly code? I know the size must be known since alloca and getelementptr both implicitly use it, but I don't see any way to get access to the size directly. I know my final compiler will have to get the size itself, but I'm just doing some simple tests directly in assembly now and am hoping there is an easy way to get the size of a
2018 Apr 18
3
Why does clang do a memcpy? Is the cast not enough? (ABI function args)
Yes, but why is it even copying the memory?  It already has a pointer which it can cast and load from -- and does so in other scenarios. I'm wondering whether this copying is somehow required and I'm missing something, or it's just an artifact of the clang emitter. That is, could it not omit the memcpy and cast the original variable? On 18/04/18 19:43, Krzysztof Parzyszek via
2018 Apr 18
4
A struct {i8,i64} has size == 12, clang says size 16
I'm creating a struct of `{i8,i64}` and `DataLayout::getTypeAllocSize` is returning `12`. `getStructLayout` also gives an `4` offset for the second element. The native ABI, and clang, for the same type are producing a size of 16, with an alignment of 8, for the second element. This is for the system triple "x86_64-linux-gnu" What could be causing this difference in alignment and
2013 Nov 08
1
[LLVMdev] UNREACHABLE executed at MCJIT.cpp:322!
It was the return type which was i64. I changed it also to my abi_int_size and it works now. I have to take care of a few other type translations, but it looks like MCJIT is working now. Thank you. On 08/11/13 18:12, Yaron Keren wrote: > Something must be wrong with the Function Type. Try to debug into > runFunction to see which if condition fails. > Just a guess, if this is on 64
2018 Apr 18
2
A struct {i8, i64} has size == 12, clang says size 16
I think I see a potential issue. My ExecutionEngine setup may not be using the same target as my object code emitting, and in this test case I'm running in the ExecutionEngine.  I'll go over this code to ensure I'm creating the same triple and see if that helps -- I'm assuming it will, since I can't imagine the exact same triple with clang would produce a different layout. On
2013 Nov 08
0
[LLVMdev] UNREACHABLE executed at MCJIT.cpp:322!
Something must be wrong with the Function Type. Try to debug into runFunction to see which if condition fails. Just a guess, if this is on 64 bit system the first argument type may be int64 but needs to be int32. Yaron 2013/11/8 edA-qa mort-ora-y <eda-qa at disemia.com> > That makes it more mysterious then since I am indeed only calling a main > function. Perhaps I have to invoke
2018 Apr 18
0
A struct {i8, i64} has size == 12, clang says size 16
It sounds like your DataLayout may not match clang's for x86_64-linux. What does it say about the alignment of i64? On Wed, Apr 18, 2018 at 12:05 PM edA-qa mort-ora-y via llvm-dev < llvm-dev at lists.llvm.org> wrote: > I'm creating a struct of `{i8,i64}` and `DataLayout::getTypeAllocSize` > is returning `12`. `getStructLayout` also gives an `4` offset for the > second
2018 Apr 18
2
Why does clang do a memcpy? Is the cast not enough? (ABI function args)
Yes, I understand that as well (it's what I'm trying to recreate in my language now). I'm really wondering why it does the copy, since from what I can tell it could just as easily cast the original value and do the load without the memcpy operation. That is, the question is about the memcpy and extra alloca -- I understand what it's doing, just not why it's doing it this way.
2016 Jul 03
2
clib `open` writes a linefeed to stdout when used in the JIT
I'm having a problem with my code generating empty lines and it appears to be the CLib `open` function generating an empty line when used within the JIT-VM. If I compile my program to an exe file it doesn't happen. I also have a lot of other code running in the VM without this problem, it's somehow particular to `open`. A chunk of my IR that calls `open`: defer_body_26:
2013 Nov 08
2
[LLVMdev] UNREACHABLE executed at MCJIT.cpp:322!
I'm trying to get MCJIT working but I get the following errors: Full-featured argument passing not supported yet! UNREACHABLE executed at MCJIT.cpp:322! I'm sure the first one will be a problem, but the second one prevents me from testing anything. I don't know how to fix the problem. My code works when using the non-MC JIT, and I added to my EngineBuilder: .setUseMCJIT(true)
2013 Oct 17
4
[LLVMdev] post-link Dwarf information appears wrong, works in JIT
I'm working on exception handling and having some trouble with type information. My personality/types work fine when running in the JIT, but when I produce object files and link them it fails. In particular, from an action record and the LSDA I get a type table entry. The problem is this doesn't appear to be pointing to a valid location. If I derefence it a segfault occurs. Are there
2012 Nov 02
4
[LLVMdev] Instruction does not dominate all uses! <badref> ??
I'm having trouble figuring out what the error "Instruction does not dominate all uses!" means. I'm trying to construct a call to a function with two parameters. The printed IR, with error, looks like this: define i32 @add(i32, i32) { EntryBlock: %2 = add i32 %0, %1 ret i32 %2 } define i32 @eval_expr() { EntryBlock: ret i32 <badref> } Instruction does not dominate
2012 Nov 11
0
[LLVMdev] IR sizeof?
Does this help? http://nondot.org/sabre/LLVMNotes/SizeOf-OffsetOf-VariableSizedStructs.txt On 11 Nov 2012, at 10:52, edA-qa mort-ora-y <eda-qa at disemia.com<mailto:eda-qa at disemia.com>> wrote: Is there a way to get the size of a type in the IR assembly code? I know the size must be known since alloca and getelementptr both implicitly use it, but I don't see any way to get
2018 Apr 19
0
Why does clang do a memcpy? Is the cast not enough? (ABI function args)
I believe the memcpy is there just as a consequence of Clang's design - different parts of the compiler own different pieces of this, so in some sense one hand doesn't see what the other is doing. Part of it is "create an argument" (memcpying the local variable into an unnamed value) and then the next part is "oh, but that argument gets passed in registers, so decompose it
2018 Apr 19
2
How to set Target/Triple of ExecutionEngine
I don't know if I'm setting the triple of my execution engine correctly.  This is leading to an issue where a struct `{i8,i64}` is not getting the same layout as the ABI expects. I setup my engine/module like this:      llvm::SmallVector<std::string,2> mattrs;      llvm::EngineBuilder builder{ unique_ptr<llvm::Module>(module) };      llvm::ExecutionEngine * ee = builder.    
2013 Nov 09
4
[LLVMdev] Error "Cannot emit physreg copy instruction"
I'm getting an error that I don't know how to fix. I've isolated the input as much as I easily can. I've attached the file that produces the problem. Just calling "llc err.ll -o err.s" generates the error. I'm going to try and isolate even further, but as I'm not sure what I'm looking for I don't know if I'll be successful. Does anybody know what this
2013 Apr 14
1
[LLVMdev] source - target code of a pass
On 14/04/13 19:50, edA-qa mort-ora-y wrote: > I don't know if there is an explicit clone method, but you could do the > printing and then parse it again. That would effectively create a clone > of the object. It appears the "llvm" namespace has several Clone functions. Thus you should be able to do what I suggested: Clone the function, run the original through the