search for: x86cfioptpass

...m 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 X86CFIOptPass::insertBasicBlockBefore(MachineFunction &MF, MachineBasicBlock *Pred, MachineFunction::iterator I){ const BasicBlock* LLVM_BB = Pred->getBasicBlock(); MachineBasicBlock * MBB = MF.CreateMachineBasicBlock(LLVM_BB); // create a MBB MBB-...

Dear All, To add to this, you can find examples of inserting NOPs for X86 in the CFI pass originally written at Lehigh University that we ported to 64-bit X86 for SVA: https://github.com/jtcriswell/SVA/blob/master/llvm/lib/Target/X86/X86CFIOptPass.cpp Alternatively, you could use an InlineAsm call at the LLVM IR level (which I think would be easier to implement). Regards, John Criswell On 7/9/15 8:56 AM, Daniel Sanders wrote: > > Hi, > > Given that you are using LLVM-IR, I expect that instruction selection > occurs after...

...sicBlock 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 X86CFIOptPass::insertBasicBlockBefore(MachineFunction&MF, >> MachineBasicBlock *Pred, >> MachineFunction::iterator I){ >> const BasicBlock* LLVM_BB = Pred->getBasicBlock(); >> MachineBasicBlock * MBB = MF.CreateMachineBasicBlock...

My pass runs after optimization passes. On Thu, Jul 9, 2015 at 1:11 PM, David Chisnall <David.Chisnall at cl.cam.ac.uk> wrote: > Hi, > > What are you trying to achieve? Inserting NOPs into LLVM IR is likely to > be pointless, as optimisations (in the IR or SelectionDAG) will remove them > before machine code generation. If you want to insert NOPs into the > generated