similar to: [LLVMdev] implicit CC register Defs cause "physreg was not killed in defining block!" assert

A physical register cannot be live across the block. So it must have a use in the block or it must be marked dead. From your dump, it looks like the CCFLAGS defs are not being marked dead. It's unclear where things went wrong, but you can step through LiveVariables to debug this. Evan On Jan 9, 2009, at 2:50 AM, Christian Sayer wrote: > Hello, > > For my backend, I define and

Evan, >A physical register cannot be live across the block. So it >must have a use in the block or it must be marked dead. From >your dump, it looks like the CCFLAGS defs are not being marked >dead. It's unclear where things went wrong, but you can step >through LiveVariables to debug this. Thanks for your response. I did quite some stepping through the llc passes, and it

> > It seems to me that the only instructions > > with dead definitions that I should not remove are the calls. Is it true? > > I would like to know if a code like this below is safe, that is, besides > > call instructions, is there other instructions that must stay in the code > > even if their definitions are dead? > > > > MachineInstr * mi = iter; >

On Thu, 29 Jun 2006, Fernando Magno Quintao Pereira wrote: > I am working in a register allocator for LLVM, and I realized that, > after I perform register allocation, there is many move instructions that > are dead code, and can safely be removed. It is easy for the RA algorithm > to remove these instructions. It seems to me that the only instructions > with dead definitions

Dear guys, I am working in a register allocator for LLVM, and I realized that, after I perform register allocation, there is many move instructions that are dead code, and can safely be removed. It is easy for the RA algorithm to remove these instructions. It seems to me that the only instructions with dead definitions that I should not remove are the calls. Is it true? I would like to know

Hi Hisham, Most likely the basic blocks are the headers of two different loops. Try running viewCFG() on the function in question to see if this is the case. Tom ----- Original Message ----- From: "Hisham Chowdhury" <hisham_chow at yahoo.com> To: llvmdev at cs.uiuc.edu Sent: Wednesday, June 16, 2010 7:22:00 PM GMT -05:00 US/Canada Eastern Subject: [LLVMdev] Loopinfo Analysis

Hello, I have a question regrading the analysis pass that generates loop info from an .ll code. My previous understanding was there will be just one loop header(in the loop info) for a particular loop. But, when i use isLoopHeader() member function from the loop info class I get 'true' return value for two different basic blocks. Note both basic blocks are loop conditional block(break

I have two questions regarding MachineMemOperands and dependence information. Q1) I noticed that MachineMemOperands are lost when two LDRs are combined and a LDRD is generated in ARMPreAllocLoadStoreOpt:::RescheduleOps. (before optimization) %reg1033<def> = LDR %reg1030, %reg0, 4100, pred:14, pred:%reg0; mem:LD4[%uglygep10] %reg1054<def> = LDR %reg1030, %reg0, 4104, pred:14,

On Sep 7, 2010, at 10:48 AM, Akira Hatanaka wrote: > I have two questions regarding MachineMemOperands and dependence information. > > Q1) I noticed that MachineMemOperands are lost when two LDRs are combined and a LDRD is generated in ARMPreAllocLoadStoreOpt:::RescheduleOps. > > (before optimization) > %reg1033<def> = LDR %reg1030, %reg0, 4100, pred:14, pred:%reg0;

Sorry, this is the part in ARMLoadStoreOptimizer.cpp that creates a LDRD instruction. Ops.pop_back(); Ops.pop_back(); // Form the pair instruction. if (isLd) { MachineInstrBuilder MIB = BuildMI(*MBB, InsertPos, dl, TII->get(NewOpc)) .addReg(EvenReg, RegState::Define)

Folks, I'm running into something which looks like a bug in linearscan allocator. Of course I can't be 100% sure it's not some unobvious mistake on my part, so I'd like to hear your opinion. First, I attach two files -- LLVM asm and the asm for my target. The problem with assembler is: on line 171 it uses register gr2, which is copied from gr6 above, on line 161. The only

My two-address target machine has sign-extension instructions to extend i8->i32 and i16->i32. When I compile this simple program: int sext (unsigned a, unsigned b, int c) { return (signed char) a + (signed short) b + c; } I get this IR: define i32 @sext(i32 %a, i32 %b, i32 %c) nounwind readnone { entry: %conv = trunc i32 %a to i8 ; <i8>

Hi all, When compiling some programs using the Mips backend i'm getting this assert message on lib/CodeGen/LiveInterval.cpp:227: "Range is not entirely in interval!" I don't know yet if it's something that is missing on the backend code or why the range to be removed it outside the interval, does anyone have any clue? A more detailed output is attached. The program i tried

Currently, the Kbuild core manipulates header search paths in a crazy way [1]. To fix this mess, I want all Makefiles to add explicit $(srctree)/ to the search paths in the srctree. Some Makefiles are already written in that way, but not all. The goal of this work is to make the notation consistent, and finally get rid of the gross hacks. Having whitespaces after -I does not matter since commit

Currently, the Kbuild core manipulates header search paths in a crazy way [1]. To fix this mess, I want all Makefiles to add explicit $(srctree)/ to the search paths in the srctree. Some Makefiles are already written in that way, but not all. The goal of this work is to make the notation consistent, and finally get rid of the gross hacks. Having whitespaces after -I does not matter since commit

Hi LLVMers, I have finally sorted out licensing issues and found some time, so I'm trying to port my PBQP register allocator to 2.4 in order to contribute it (if you want it). I've run into a bug that has me confused though. I'm currently failing the following assertion: llc: VirtRegMap.cpp:1733: void<unnamed>::LocalSpiller::RewriteMBB(llvm::MachineBasicBlock&,

On Sep 3, 2008, at 5:58 AM, Lang Hames wrote: > Hi LLVMers, > > I have finally sorted out licensing issues and found some time, so I'm > trying to port my PBQP register allocator to 2.4 in order to Nice! We would definitely welcome your contribution. > > contribute it (if you want it). I've run into a bug that has me > confused though. > > I'm currently

On Tue, 2016-12-06 at 17:41 +0200, Michael S. Tsirkin wrote: > It seems that there should be a better way to do it, > but this works too. In some cases there might be: > --- a/drivers/s390/virtio/Makefile > +++ b/drivers/s390/virtio/Makefile > @@ -6,6 +6,8 @@ > ?# it under the terms of the GNU General Public License (version 2 > only) > ?# as published by the Free

On Tue, 2016-12-06 at 17:41 +0200, Michael S. Tsirkin wrote: > It seems that there should be a better way to do it, > but this works too. In some cases there might be: > --- a/drivers/s390/virtio/Makefile > +++ b/drivers/s390/virtio/Makefile > @@ -6,6 +6,8 @@ > ?# it under the terms of the GNU General Public License (version 2 > only) > ?# as published by the Free

Suppose I need to align an address register to even boundary. Since address register can't be AND-ed with anything, I move the value into general purpose register, to "and" and then move it into address register. Unfortunately, the register allocator crashes. Here's machine code: %reg1030 = - %reg1027, 1 %reg1031 = move %reg1030 %reg1032 = + %reg1031,