similar to: [LLVMdev] Stack alignment in leaf functions

Hi, I have a problem getting a properly aligned stack for my LLVM backend. I've asked about this previously, but unfortunately only now could try the suggested solution. For reference, here's the original message from me: http://mail.cs.uiuc.edu/pipermail/llvmdev/2004-July/001388.html And here's reply from Chris: http://mail.cs.uiuc.edu/pipermail/llvmdev/2004-July/001390.html The

Hello, it seems the Prolog/Epilog insertion does not correctly align stack for me. Consider the PEI::calculateFrameObjectOffsets method. It only aligns the stack if FFI->hasCalls() is true. The only place where MachineFrameInfo::setHasCalls is invoked is PEI::saveCallerSavedRegisters and the value 'true' is only passed when there are instructions with opcodes equal

On Tue, 22 Mar 2005, Vladimir Prus wrote: > The PrologEpilogInserter.cpp file aligns the stack only if > MachineFrameInfo::hasCalls returns true, which happens only if the function > has "call frame setup instruction" which my backend does not generate. > Chris suggested adding explicit MachineFrameInfo::setHasCalls call, which I've > tried, but it does not help. The

I investigated the MachineFunctionPass (that is runOnMachineFunction, I believe). In my experimentation it didn't seem that the MachineFrameInfo was populated (it consistently said that the stack depth was 0, for example). I might have been doing something wrong? On Fri, Jul 8, 2011 at 5:21 PM, John Criswell <criswell at illinois.edu> wrote: > On 7/8/11 4:09 PM, Andrew Ruef wrote:

Hi, Attached is a patch I'm testing. It changes how "MachineFrameInfo::HasCalls" is calculated. Basically, the way it's calculated now is in PEI. And it only looks for frame adjustments (or inline ASM) to determine if the function has a call or not. This way is much more accurate and occurs much sooner. But it breaks this test:

On 7/8/11 4:49 PM, Andrew Ruef wrote: > I investigated the MachineFunctionPass (that is runOnMachineFunction, > I believe). A MachineFunctionPass is a class that you inherit from to write a transform that operates on MachineInstrs (i.e., native code instructions generated from the LLVM IR instructions). The runOnMachineFunction() method is its entry point (i.e., the code generator

On Tuesday 22 March 2005 20:34, Chris Lattner wrote: > Can you explain the problem in more detail? Specifically the LLVM code > gneerator assumes that there is some alignment that the stack is required > to have as part of its ABI. For example, in X86 target machine, the stack > is 8-byte aligned on entry to function calls. > > What this means is that the frame info can assume

yOn Wed, 23 Mar 2005, Vladimir Prus wrote: >> How is your target different here? Can you give an example of why this >> causes a problem? > > Here's the code which computes the hasCalls flag: > > bool HasCalls = false; > > for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) > for (MachineBasicBlock::iterator I = BB->begin(); I

The following problems happens with architectures, where stack alignment is smaller than the biggest preferred alignment for any data type SP pointer may point anywhere with alignment of stack alignment (4 in our case) SelectionDAGBuilder however calls CreateStackObject with preferred alignment is given data type(8 in our problemaric case. The ABI alignment for this data type is only 4) This

Hi all, I am trying to write a pass where i am creating a clone of a function (the only difference being, the new function returns void , instead of any value). I am creating a new Function Type with a void return type (rest being the same as original function), and using this i am creating a new function body. Then, i clone the body of the old function into new function, but when ever i

Hi, I'm gonna try to give some feedback, but I have only been working with LLVM for a few days, so don't take what I'm saying without verifying :-) > BasicBlock *ProgSlicer::CloneBasicBlock(const BasicBlock *BB, > DenseMap<const Value*, Value*> &ValueMap, > const char *NameSuffix, Function *F) { > > BasicBlock

I am new to the LLVM, and need some help with this points. 1. how can we add special code for the Prolog/Epilog for some certain functions, this should be done with machinefunction pass, rt? 2. Basically, I want to get the function stack frame, that is the size and the initial position. I found int64_t llvm::MachineFrameInfo::getObjectSize ( int *ObjectIdx* ) const[inline] This method is

On Fri, 6 Oct 2006, [UTF-8] Rafael Esp?ndola wrote: > In ARM the stack should be 8 bytes aligned during function calls. A > function that has at least one function call then has a stack size of > 8 bytes. PEI::calculateFrameObjectOffsets corretly computes this > correctly. > > The problem is that the alignment is computed before adding space for > the call frame size. This is

In ARM the stack should be 8 bytes aligned during function calls. A function that has at least one function call then has a stack size of 8 bytes. PEI::calculateFrameObjectOffsets corretly computes this correctly. The problem is that the alignment is computed before adding space for the call frame size. This is done in emitProlog. Currently the ARM backend has a bug in that it doesn't align

> This sounds like the ADJCALLSTACK DOWN/UP 'instructions' around the call > aren't set right, or you have declared a SP offset. It doesn't look like > the ARM backend does this, so this is probably the problem. The ARM backend currently doesn't use a frame pointer. It uses the same technique of the PPC backend to avoid add/subs around calls. In the PPC backend we

On 7/8/11 4:09 PM, Andrew Ruef wrote: > Hi list, > > I am trying to implement the technique outlined in the following > paper: http://www.cs.umd.edu/~mwh/papers/martin10ownership.html > <http://www.cs.umd.edu/%7Emwh/papers/martin10ownership.html> in LLVM. > My approach so far involves the use of an IR level transform (via > runOnFunction) to identify memory loads and

I am running into an issue where if I have multiple functions compiled in the same compilation unit the stack offset is not starting at zero. For example: func1(...) { ... } func2(...) { ... } Say the first function uses 64 bytes of the stack and an assumed offset of 0 and the second function uses 32 bytes of the stack but an assumed offset of 64. I've found out how to get the

Hello All, I just svn update % svn info . Path: . URL: http://llvm.org/svn/llvm-project/llvm/trunk Repository Root: http://llvm.org/svn/llvm-project Repository UUID: 91177308-0d34-0410-b5e6-96231b3b80d8 Revision: 54012 Node Kind: directory Schedule: normal Last Changed Author: wangmp Last Changed Rev: 54007 Last Changed Date: 2008-07-25 03:30:26 +0200 (Fri, 25 Jul 2008) make[3]: Entering

Hi Dale, yes it's just stack alignment. Unfortunately your patch doesn't make any difference. Thanks for thinking about this, Duncan. On Friday 27 June 2008 19:51:00 Dale Johannesen wrote: > On Jun 27, 2008, at 3:11 AMPDT, Duncan Sands wrote: > > FAIL: test/CodeGen/X86/vec_shuffle-10.ll > > Failed with exit(1) at line 3 > > while running: llvm-as <

On Jun 27, 2008, at 3:11 AMPDT, Duncan Sands wrote: > FAIL: test/CodeGen/X86/vec_shuffle-10.ll > Failed with exit(1) at line 3 > while running: llvm-as < test/CodeGen/X86/vec_shuffle-10.ll | llc - > march=x86 -mattr=+sse2 | not grep {sub.*esp} > subl $16, %esp > subl $16, %esp > child process exited abnormally Is the code actually loading and storing