similar to: [LLVMdev] Customizing PEI::calculateFrameObjectOffsets()

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

> That is irrelevant. The PEI code needs to know how much stack space is > required for each call to allocate and align the stack frame properly. It > gets this info from the ADJCALLSTACK instructions. I see. Looking at PEI::calculateCalleeSavedRegisters shows that the ADJCALLSTACK instructions is used to set up MaxCallFrameSize. Adding debug prints also show that in the example code

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

On Sat, 7 Oct 2006, [UTF-8] Rafael Esp?ndola wrote: >> 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

> 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

Hello, the calculateFrameObjectOffsets methods in CodeGen/PrologEpilogEmitter.cpp does not work for me, since it asserts if stack grows up, and when assert is commented out, allocates spill slots in the same location as function arguments, which is not right. I've tried to fix that, and a patches. It merely adds if (StackGrowsDown) everywhere, so that the current logic should not be

On Tue, May 12, 2009 at 11:55 PM, Chris Lattner <clattner at apple.com> wrote: > Dan, can you add IVUsers.cpp to the appropriate cmakefile? > > -chris > > > On May 12, 2009, at 10:54 PM, OvermindDL1 wrote: > >> On Tue, May 12, 2009 at 11:40 PM, Chris Lattner <clattner at apple.com> >> wrote: >>> >>> On May 12, 2009, at 10:24 PM,

Hello, after some time I'm trying to build my code with the current CVS of LLVM, and have a problem. The mentioned file, around line 184, contains: if (FixedSlot == FixedSpillSlots+NumFixedSpillSlots) { // Nope, just spill it anywhere convenient. FrameIdx = FFI->CreateStackObject(RegInfo->getSpillSize(Reg)/8,

hi, list, i am making a llvm compiler for shader-like programs. as we known, shader programs are short and have less function calls. i found that i have to save/restore callee-saved register(CSR) in prolog and epilog. because I can violate ABI from driver(c code) and shader, i plan to append the attribute 'noreturn' to all shader functions. in PrologEpilogInserter.cpp, you can find that

Hi all, Virtual ISAs such as WebAssembly and NVPTX use infinite virtual register sets instead of traditional phsyical registers. PrologEpilogInserter is run after register allocation and asserts that all virtuals have been allocated but doesn't otherwise depend on this if scavenging is not needed. We'd like to use the target-independent PEI code for WebAssembly, so we're proposing a

Hi Jakob, I have spent last 4 weeks trying to figure out how to implement Interprocedural Register Allocation. I must admit that I was really overwhelmed with LLVM's codebase while trying to figure this out :) There is so much to know! I think I have reached a point where I have some sort of basic understanding of what needs to be done, but I need some help from here on. So here is the

On 08/27/2010 11:05, Dale Johannesen wrote: >>>> Function only has on BB. Is this wrong that it has both >>>> TCRETURNri64 and RET in one BB? >>> >>> Yes, that is wrong. The reason emitEpilogue isn't lowering the >>> TCRETURN is that it doesn't see it, it only sees the RET. The real >>> problem will be where that RET is

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

I have a question about register scavenger. I am considering using register scavenger for MIPS to free up register AT which is currently reserved to load large immediates. All targets which currently use register scavenger to search for a scratch register (ARM, CellSPU, PowerPC and XCore) override function processFunctionBeforeCalleeSavedScan and call RegisterScavenger::setScavengingFrameIndex

I'm seeing the following warning when compiling LLVM trunk in a Release build: llvm/lib/CodeGen/PrologEpilogInserter.cpp: In member function ‘void llvm::PEI::scavengeFrameVirtualRegs(llvm::MachineFunction&)’: llvm/lib/CodeGen/PrologEpilogInserter.cpp:770: warning: ‘PrevValue’ may be used uninitialized in this function I briefly looked at the code and it looks like PrevValue is

The X86 backend has this code: X86TargetMachine::X86TargetMachine(const Module &M, IntrinsicLowering *IL) : .... FrameInfo(TargetFrameInfo::StackGrowsDown, 8/*16 for SSE*/, 4), That is, it uses "4" as local area offset. Based on prior discussion this should mean that the local area starts and address ESP+4. Is this really true? On X86 stack grows down, so

For a particular target I would like to replace some of the "standard" passes with customized versions. What would be the cleanest way to do this? At the moment I cannot see a good way of removing an existing pass from within the target library.

On Wed, 9 Jun 2004, Vladimir Prus wrote: > > The X86 backend has this code: > > X86TargetMachine::X86TargetMachine(const Module &M, IntrinsicLowering *IL) > : .... > FrameInfo(TargetFrameInfo::StackGrowsDown, 8/*16 for SSE*/, 4), > > That is, it uses "4" as local area offset. Based on prior discussion this > should mean that the local

Hi, Nicolas > Could you point me where those hooks are in the llvm code? I didn't find > any. Look into PrologEpilogInserter.cpp::PEI::runOnMachineFunction(). There are calls to hooks inside TargetRegisterInfo: TargetRegisterInfo::processFunctionBeforeCalleeSavedScan() and TargetRegisterInfo::processFunctionBeforeFrameFinalized(). Maybe they are not so convenient when working via JIT

Hi John, Unless anyone else has any comments. I recommend you check in the PEI patches so we can start testing it as llcbeta. Chris, should I commit the patch for John or can you grant him commit access (since part of his patch has already been committed)? Evan On Mar 16, 2009, at 3:23 PM, John Mosby wrote: > Here is the latest shrink wrapping patch, with fixes for issues >