similar to: [LLVMdev] IMPLICIT_DEF

Hi, I have a problem regarding sub-register definitions and LiveIntervals on our target. When a subregister is defined, other parts of the register are always left untouched - they are neither read or def:ed. It however seems that Codegen treats subregister definitions as somehow clobbering the whole register. The SSA-code looks like this after isel: (Reg0 and Reg1 are 16bit registers. Reg2,

Hi, I'm working on the iterated register coalescing graph coloring allocator and try to test it with all backends available currently in LLVM. Initial tests with most of the backends are successful. It turned out that my allocator triggers a specific assertion in the RegScavenger and only for the ARM target. It looks like the LR register is used for frame pointer related things, but it is

2009/1/13 Evan Cheng <echeng at apple.com>: > > On Jan 7, 2009, at 2:48 AM, Roman Levenstein wrote: > >> bb368: 0x8fdad00, LLVM BB @0x8fc2c98, ID#1: >> Predecessors according to CFG: 0x8fdac90 (#0) >> %R0<def> = MOVi 0, 14, %reg0, %reg0 >> *** STR %LR<kill>, %R0<kill>, %reg0, 0, 14, %reg0, Mem:ST(4,4) >> [0x8fc2d68 + 0]

On Jan 7, 2009, at 2:48 AM, Roman Levenstein wrote: > bb368: 0x8fdad00, LLVM BB @0x8fc2c98, ID#1: > Predecessors according to CFG: 0x8fdac90 (#0) > %R0<def> = MOVi 0, 14, %reg0, %reg0 > *** STR %LR<kill>, %R0<kill>, %reg0, 0, 14, %reg0, Mem:ST(4,4) > [0x8fc2d68 + 0] > %LR<def> = LDR <fi#0>, %reg0, 0, 14, %reg0 >

On Jan 13, 2009, at 12:27 AM, Roman Levenstein <romix.llvm at googlemail.com > wrote: > 2009/1/13 Evan Cheng <echeng at apple.com>: >> >> On Jan 7, 2009, at 2:48 AM, Roman Levenstein wrote: >> >>> bb368: 0x8fdad00, LLVM BB @0x8fc2c98, ID#1: >>> Predecessors according to CFG: 0x8fdac90 (#0) >>> %R0<def> = MOVi 0, 14, %reg0,

This looks like a bar in ARMInstrInfo.td: BX_RET should be marked with Uses = [LR] since it uses LR. However, this won't work if there is a call BL before the BX_RET. BL is marked as if it implicitly define LR. So we'll end up with this (hello world example): Live Ins: %LR %R7 %SP<def> = SUBri %SP<kill>, 8, 14, %reg0, %reg0 STR %LR<kill>, %SP,

Hi, Recently code using IMPLICIT_DEF and INSERT_SUBREG started to break: %vreg9<def> = IMPLICIT_DEF %vreg10<def> = INSERT_SUBREG %vreg9<kill>, %vreg1<kill>, hi %vreg12<def> = sub %vreg10<kill>, %vreg11<kill> => %vreg10<def> = IMPLICIT_DEF %vreg10:hi<def> = COPY %vreg1<kill>

On Jan 9, 2009, at 11:37 AMPST, Evan Cheng wrote: > This looks like a bar in ARMInstrInfo.td: > > BX_RET should be marked with Uses = [LR] since it uses LR. However, > this won't work if there is a call BL before the BX_RET. BL is marked > as if it implicitly define LR. So we'll end up with this (hello world > example): PPC has the call (BL) marked with Defs=LR and the

Hi again, 2009/1/13 Evan Cheng <evan.cheng at apple.com>: > > > On Jan 13, 2009, at 12:27 AM, Roman Levenstein <romix.llvm at googlemail.com> > wrote: > >> 2009/1/13 Evan Cheng <echeng at apple.com>: >>> >>> On Jan 7, 2009, at 2:48 AM, Roman Levenstein wrote: >>> >>>> bb368: 0x8fdad00, LLVM BB @0x8fc2c98, ID#1:

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,

I used llvm-stress to find a similar problem on x86-64. See http://llvm.org/bugs/show_bug.cgi?id=12821. BTW, llvm-stress is a great tool! /Patrik Hägglund ________________________________ From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On Behalf Of Jakob Stoklund Olesen Sent: den 9 maj 2012 18:21 To: Jonas Paulsson Cc: llvmdev at cs.uiuc.edu Subject: Re: [LLVMdev]

Hi. I am trying to run LLVM with JIT on ARM processor (Android phone). Currently I have problems using external functions. Any call to external function crashes and gives me signal 11 (SIGSEGV) at some random address. I'm trying to run following C code: *** extern void add1(int* x); int main() { int a = 10; int b = 20; add1(&b); int c = a + b; return c; } *** It gives

On May 9, 2012, at 6:27 AM, Jonas Paulsson <jonas.paulsson at ericsson.com> wrote: > Hi, > > Recently code using IMPLICIT_DEF and INSERT_SUBREG started to break: > > %vreg9<def> = IMPLICIT_DEF > %vreg10<def> = INSERT_SUBREG %vreg9<kill>, %vreg1<kill>, hi > %vreg12<def> = sub %vreg10<kill>,

Hi, I have a MachineInstr that writes to a subreg, but clobbers the superreg. How should I BuildMI this instruction? I try to do a IMPLICIT_DEF super_reg and then write to a subreg of that super register , but it gets DCE:ed. Is there a way to express this clobbering of a superregister? thanks, Jonas -------------- next part -------------- An HTML attachment was

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;

Hi, while writing my register allocator, I have come across a case which confuses me because the llvm definition cannot be mapped to machine code. For instance I come across (1) and I reduce it to (2). However a copy instruction cannot move from EDX to CX. What mechanics in LLVM will tell me that I cannot make this move during register allocation, or how can I tell from (1) that I cannot execute

Hi Evan, Thanks for your feedback! 2009/1/7 Evan Cheng <evan.cheng at apple.com>: > > On Jan 7, 2009, at 2:48 AM, Roman Levenstein wrote: > > > As you can see, PrologEpilogInserter has inserted at the beginning > of the function some code for manipulation of the frame pointer and > this inserted code uses the LR register. > As far as I understand,

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)

I am wondering about register allocation when there is a kill flag on the MachineOperand. Do I need to remove the kill flag? This code below is just an example from test\CodeGen\X86\xor.ll # Machine code for function test3: Frame Objects: fi#-2: size=4, align=4, fixed, at location [SP+8] fi#-1: size=4, align=8, fixed, at location [SP+4] Function Live Outs: %EAX BB#0: derived from LLVM BB

Hi everyone, I am trying to expand one instruction into multiple instructions on MIPS. For example, I try to expand: sh src, imm(dst) into: (1) sb src, imm(dst) (2) srl reg0, src, 8 (3) sb reg0, (imm+1)(dst) Here, reg0 are created with createVirtualRegister. However, instr(2) will not be emitted because reg0 is useless before reg0 is defined in instr(3), it is wrong! So how to prevent the