similar to: [LLVMdev] Why the same MachineBasicBlock converted to binary code twice?

Aaron, I mailed in the same mail twice (by mistake), you answered both copies. Differently! In any case, I've re-read what exists. I'm dumping what I understand here, so that we can discuss in detail. I'm using MachO as the example object format, as the ELF code is totally broken and outdated. Lets use the following as the basis for our discussion? There are 3 classes which

>> Sorry, I disagree actually the MachineCodeEmitter or the >> 'MachineCodeWritter' does not do any file handling at all. Do look at the >> code for the MachineCodeWritter and you will see it only writes to memory >> and if it reaches the end of the allotted memory I believe higher ordered >> logic reallocates a larget buffer and starts again from scratch.

I don't think you can. The BasicBlock is a member of MachineBasicBlock. It is not inherited, so it cannot be cast. The number of the MachineBasicBlock is not the same as any BasicBlock values. So MachineFunction::getMachineBasicBlock( BasicBlock::{get the number} ) cannot work. I do not see much in the basic block which can identify it. So you can search for it. typedef struct findBlock {

Also note: there may be multiple MachineBasicBlock's for a single BasicBlock. - David M On Fri, Oct 15, 2010 at 4:59 AM, Jeff Kunkel <jdkunk3 at gmail.com> wrote: > I don't think you can. > > The BasicBlock is a member of MachineBasicBlock. It is not inherited, > so it cannot be cast. The number of the MachineBasicBlock is not the > same as any BasicBlock values.

Hello, we can get BasicBlock from MachineBasicBlock through MachineBasicBlock::getBasicBlock() function, but how can I get MachineBasicBlock of a BasicBlock? Thank you!

Hi all, I think that I came somewhat closer to a solution for splitting a MachineBasicBlock for a PSEUDO_CALL_R instruction and having a label to the new MBB: For following piece of code: --- typedef int callme_t(int a, int b); callme_t* c01; int foo(int a, int b) { return c01(a,b); // MachineBasicBlock will be split at call instruction } --- I have initially following correspondence: BB1

I want to be able to do two things with LLVM (both just before code emission): 1. Insert a MachineBasicBlock just before a MachineBasicBlock. There is a function called AddPredecessor(). However, the comment says that it does not update the actual CFG. I want to redirect all CFG edges that are incoming to this MachineBasicBlock to the new one I create, and add just one outgoing edge (no branch)

I am trying to create such module with API (it's equivalent to c++: const char* ss[] = {"s1","s2"};): @ss = global [2 x i8*] [i8* getelementptr inbounds ([3 x i8]* @.str1, i32 0, i32 0), i8* getelementptr inbounds ([3 x i8]* @.str2, i32 0, i32 0)] ; <[2 x i8*]*> [#uses=0] @.str1 = private constant [3 x i8] c"s1\00", align 1 ; <[3 x i8]*> [#uses=1]

Dear LLVM, I was wondering what's the difference between BasicBlock and MachineBasicBlock in LLVM. If I want to solve a data flow equation problem, which one should I use? Thanks, Jerry

I have ran under valgrind memcheck the process using libLLVM-2.9.so (rev.126022) and got several errors: ==24227== Invalid read of size 1 ==24227== at 0x40274C9: memcpy (mc_replace_strmem.c:497) ==24227== by 0x40D5B84: char* std::string::_S_construct<char const*>(char const*, char const*, std::allocator<char> const&, std::forward_iterator_tag) (in

Hi Evan, Evan Cheng wrote: > 1) How are you computing size of the method being > jitted? I add a new pass with addSimpleCodeEmitter, with the emitter being a SizeEmitter. Since the target calls the emitter with functions such as writeByte, writeWord, etc.... the SizeEmitter class implements these function by incrementing a counter. At the end of the pass, the code size of the

Can you please post the code to split a MachineBasicBlock? I am trying to split a MachineBasicBlock at a specific instruction in the MBB, let us say, into MBB1 and MBB2. This instruction should go into MBB2. Also MBB1 should have an unconditional branch to MBB2 as the terminator. (quite similar to splitBasicBlock in BasicBlock.cpp) Meanwhile, I am trying to come up with a variant of

Hi, Two questions. 1) How are you computing size of the method being jitted? 2) Why not simply add the functionality of allocating emission buffer of specific size to MachineCodeEmitter instead? Thanks, Evan On Mar 30, 2008, at 12:05 PM, Nicolas Geoffray wrote: > Hi everyone, > > vmkit requires to know the size of a jitted method before emitting > the method. This allows to

I have a module having the blockaddress instruction. When I link it into another module and delete the original, blockaddress disappears and is replaced by inttoptr (i32 1 to i8*). Please compile and run the attached program to see the demo of this problem. Right after linking modules, blockaddress still exists: @switch.bbs = internal global [3 x i8*] [i8* blockaddress(@my_func,

Hi, Why does a MachineBasicBlock have multiple terminator instructions (unlike BasicBlock, which can only have one) ? Thanks, Tom -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20160324/86ab8873/attachment-0001.html>

Hi, > On Mar 24, 2016, at 10:58 AM, Tom Chen via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > Hi, > Why does a MachineBasicBlock have multiple terminator instructions (unlike BasicBlock, which can only have one) ? Think of it as predicated instructions. E.g., bool = icmp if bool : br if br else As for why, we could indeed have split those terminators into several basic

So in your example there are two terminators in the basic block (`br if` and `br else`)? 2016-03-24 14:15 GMT-04:00 Quentin Colombet <qcolombet at apple.com>: > Hi, > > > On Mar 24, 2016, at 10:58 AM, Tom Chen via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > > > Hi, > > Why does a MachineBasicBlock have multiple terminator instructions >

Hi everyone, vmkit requires to know the size of a jitted method before emitting the method. This allows to allocate the correct size for the method. The attached patch creates this functionality when the flag SizedMemoryCode is on. In order to implement this functionality, i had to virtualize some MachineCodeEmitter functions. Is it OK to commit the patch? Thanks, Nicolas --------------

Hi all, I am really stumped on a problem for long. I could not figure out why. That is why i am here. OK, here is the problem: I tried to insert a MachineBasicBlock into a function. Here is the code snippet: // insert a machine basic block with the error_label into MF and before I // Pred is the predecessor of the block to be inserted // the new basic block is inserted right before I void

Evan Cheng wrote: > On Apr 1, 2008, at 12:50 AM, Nicolas Geoffray wrote: > > > That's a hack. :-) It is if you think that code emitter should only be used for actually writing somewhere the data. It is not if you find it another useful utility ;-) > Some targets already have ways to compute the exact > size of a function. See ARM::GetFunctionSize()