Displaying 20 results from an estimated 300 matches similar to: "[LLVMdev] Virtual register problem in X86 backend"
2014 Dec 10
2
[LLVMdev] Virtual register problem in X86 backend
Hi,
Thx for your help...
Here is the IR code:
; ModuleID = 'foo_bar.c'
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@.str = private unnamed_addr constant [6 x i8] c"MAIN\0A\00", align 1
; Function Attrs: nounwind uwtable
define i32 @main(i32 %argc, i8** %argv) #0 {
entry:
%retval = alloca i32,
2014 Oct 28
2
[LLVMdev] Problem in X86 backend (again)
Hi,
I'm still having problems implementing my custom inserter in the X86 backend.
I found a solution to my last problem (http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-October/078296.html), by using a virtual register.
The binary works when it's compiled in -O0, but not in -O1,-O2,...
I really can't figure what I'm doing wrong... Any idea?
Here is the code of my custom
2014 Oct 29
2
[LLVMdev] Problem in X86 backend (again)
>> // Increment loop variable and jmp
>> BuildMI(*MBB_erase, MBB_erase->end(), db, >> TII->get(X86::ADD64ri32),reg).addReg(reg).addImm(8);
>
> It looks like this instruction is defining virtual register "reg" the second time.
Thx for your answer...
Why would it define it again? I just want to use this register and add something to it...
Cheers
2013 Feb 18
1
[LLVMdev] splitting a branch within a pseudo
Some stuff did not get pasted in properly.
static MachineBasicBlock* ExpandCondMov(MachineInstr *MI,
MachineBasicBlock *BB,
DebugLoc dl,
const MipsSubtarget *Subtarget,
const TargetInstrInfo *TII,
bool isFPCmp, unsigned Opc) {
//
2008 Jul 10
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Cool, that worked. New patch attached...
Cheers,
Gary
Evan Cheng wrote:
> Just cast both values to const TargetRegisterClass*.
>
> Evan
>
> On Jul 10, 2008, at 7:36 AM, Gary Benson wrote:
> > Evan Cheng wrote:
> > > How about?
> > >
> > > const TargetRegisterClass *RC = is64Bit ? &PPC:GPRCRegClass :
> > > &PPC:G8RCRegClass;
>
2013 Feb 18
0
[LLVMdev] splitting a branch within a pseudo
This is the old MIPS I code that sort of does what I need to do. This
seems really involved to do such a simple thing.
Maybe there are now helper classes for this or some better example I can
look at. I suppose I can mimick this if people say this just the correct
way to do this in LLVM.
static MachineBasicBlock* ExpandCondMov(MachineInstr *MI,
MachineBasicBlock *BB,
2008 Jul 08
0
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
PPCTargetLowering::EmitInstrWithCustomInserter has a reference
to the current MachineFunction for other purposes. Can you use
MachineFunction::getRegInfo instead?
Dan
On Jul 8, 2008, at 1:56 PM, Gary Benson wrote:
> Would it be acceptable to change MachineInstr::getRegInfo from private
> to public so I can use it from
> PPCTargetLowering::EmitInstrWithCustomInserter?
>
>
2008 Jul 11
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Hi Evan,
Evan Cheng wrote:
> This does not patch cleanly for me (PPCISelLowering.cpp). Can you
> prepare a updated patch?
This should work, though I won't have access to my test box now until
next Thursday so no guarantees :)
Cheers,
Gary
--
http://gbenson.net/
-------------- next part --------------
Index: lib/Target/PowerPC/PPCISelLowering.h
2008 Jul 11
0
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Hi Gary,
This does not patch cleanly for me (PPCISelLowering.cpp). Can you
prepare a updated patch?
Thanks,
Evan
On Jul 10, 2008, at 11:45 AM, Gary Benson wrote:
> Cool, that worked. New patch attached...
>
> Cheers,
> Gary
>
> Evan Cheng wrote:
>> Just cast both values to const TargetRegisterClass*.
>>
>> Evan
>>
>> On Jul 10, 2008, at 7:36
2008 Jul 10
0
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Just cast both values to const TargetRegisterClass*.
Evan
On Jul 10, 2008, at 7:36 AM, Gary Benson wrote:
> Evan Cheng wrote:
>> How about?
>>
>> const TargetRegisterClass *RC = is64Bit ? &PPC:GPRCRegClass :
>> &PPC:G8RCRegClass;
>> unsigned TmpReg = RegInfo.createVirtualRegister(RC);
>
> I tried something like that yesterday:
>
> const
2008 Jul 10
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Evan Cheng wrote:
> How about?
>
> const TargetRegisterClass *RC = is64Bit ? &PPC:GPRCRegClass :
> &PPC:G8RCRegClass;
> unsigned TmpReg = RegInfo.createVirtualRegister(RC);
I tried something like that yesterday:
const TargetRegisterClass *RC =
is64bit ? &PPC::GPRCRegClass : &PPC::G8RCRegClass;
but I kept getting this error no matter how I arranged it:
2008 Jun 30
0
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
You need to insert new basic blocks and update CFG to accomplish this.
There is a hackish way to do this right now. Add a pseudo instruction
to represent this operation and mark it usesCustomDAGSchedInserter.
This means the intrinsic is mapped to a single (pseudo) node. But it
is then expanded into instructions that can span multiple basic
blocks. See
2008 Jul 09
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Ah, didn't see that, that's what comes of trying to do something at
5pm :) I attached an updated patch which creates a virtual register
instead of using R0. How does this look?
Cheers,
Gary
Dan Gohman wrote:
> PPCTargetLowering::EmitInstrWithCustomInserter has a reference
> to the current MachineFunction for other purposes. Can you use
> MachineFunction::getRegInfo instead?
2008 Jul 08
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Would it be acceptable to change MachineInstr::getRegInfo from private
to public so I can use it from PPCTargetLowering::EmitInstrWithCustomInserter?
Cheers,
Gary
Evan Cheng wrote:
> Look for createVirtualRegister. These are examples in
> PPCISelLowering.cpp.
>
> Evan
> On Jul 8, 2008, at 8:24 AM, Gary Benson wrote:
>
> > Hi Evan,
> >
> > Evan Cheng wrote:
2008 Jun 30
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Chris Lattner wrote:
> On Jun 27, 2008, at 8:27 AM, Gary Benson wrote:
> > def CMP_UNRESw : Pseudo<(outs), (ins GPRC:$rA, GPRC:$rB, i32imm:
> > $label),
> > "cmpw $rA, $rB\n\tbne- La${label}_exit",
> > [(PPCcmp_unres GPRC:$rA, GPRC:$rB, imm:
> > $label)]>;
> > }
> >
> > ...and
2008 Jul 02
2
[LLVMdev] Implementing llvm.atomic.cmp.swap.i32 on PowerPC
Evan Cheng wrote:
> You need to insert new basic blocks and update CFG to accomplish this.
> There is a hackish way to do this right now. Add a pseudo instruction
> to represent this operation and mark it usesCustomDAGSchedInserter.
> This means the intrinsic is mapped to a single (pseudo) node. But it
> is then expanded into instructions that can span multiple basic
>
2013 Feb 17
4
[LLVMdev] splitting a branch within a pseudo
After discussions last night, I'm leaning towards going legit with all
my pseudo expansions in Mips 16.
Some I think I can clearly do by just putting in the proper side effects
of implicit registers (T8 the condition code register as used by mips 16).
But I'm still left with some pseudos that have jmp .+4 type instructions
in them.
The original Mips port was to Mips I and Mips I,
2016 Feb 03
2
TableGen register class
Hi,
Assume I define registers R0...R15 and two register classes RegA and RegB.
RegA contains R0 to R7 while RegB contains R0 to R15.
Then I check the machine instruction, it seems that in some cases, the
%vreg0 belongs to RegB; in other cases %vreg1 belongs to RegA_RegB. Can you
tell me how TableGen decides which is which? At first, I guess &verg0 will
be assigned by R8 to R15 only so that
2017 Jul 24
2
How to lower a 'Store' node using the list<dag> pattern.
Hi,
I'm trying to complete the lowering for a new microcontroller. I'm using LLVM 3.8.
For now this lowering crashes on 'Store' node, which is actually not yet defined.
I've tried to map the ISel 'Store' node to architecture specific instructions.
I've define the following semantic to my architecture specific instructions:
def MOVSUTO_SU_rr :
2013 Sep 17
2
[LLVMdev] Codegen performance issue: LEA vs. INC.
Hi all.
I'm looking for an advice on how to deal with inefficient code generation for Intel Nehalem/Westmere architecture on 64-bit platform for the attached test.cpp (LLVM IR is in test.cpp.ll).
The inner loop has 11 iterations and eventually unrolled.
Test.lea.s is the assembly code of the outer loop. It simply has 11 loads, 11 FP add, 11 FP mull, 1 FP store and lea+mov for index