similar to: [LLVMdev] IMPLICIT_DEF?

What's the value produced by an INSERT_SUBREG node? Is it a chain? Can I use to set a superreg of i16 type with two i8 values, and use the supperreg as an operand somewhere else? - Sanjiv -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20081002/f07bc88c/attachment.html>

In LiveIntervals::processImplicitDefs() we have this: for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(Reg), UE = mri_->use_end(); UI != UE; ) { MachineOperand &RMO = UI.getOperand(); MachineInstr *RMI = &*UI; ++UI; MachineBasicBlock *RMBB = RMI->getParent(); if (RMBB == MBB) continue; const

On Thu, 2008-10-02 at 11:19 -0700, Evan Cheng wrote: > > On Oct 2, 2008, at 11:02 AM, Sanjiv.Gupta at microchip.com wrote: > > > What’s the value produced by an INSERT_SUBREG node? Is it a chain? > > > No, insert_subreg returns a value: > > > v1 = insert_subreg v2, v3, idx > > > v1 and v2 will have the same type, e.g. i16, and v3 must have a >

On Tue, 2008-10-14 at 10:19 -0700, Evan Cheng wrote: > You need to specify sub-register == super-register, idx relationship. > See X86RegisterInfo.td: > > def x86_subreg_8bit : PatLeaf<(i32 1)>; > def x86_subreg_16bit : PatLeaf<(i32 2)>; > def x86_subreg_32bit : PatLeaf<(i32 3)>; > > def : SubRegSet<1, [AX, CX, DX, BX, SP, BP, SI, DI, >

You need to specify sub-register == super-register, idx relationship. See X86RegisterInfo.td: def x86_subreg_8bit : PatLeaf<(i32 1)>; def x86_subreg_16bit : PatLeaf<(i32 2)>; def x86_subreg_32bit : PatLeaf<(i32 3)>; def : SubRegSet<1, [AX, CX, DX, BX, SP, BP, SI, DI, R8W, R9W, R10W, R11W, R12W, R13W, R14W, R15W], [AL, CL,

On Oct 2, 2008, at 11:02 AM, Sanjiv.Gupta at microchip.com wrote: > What’s the value produced by an INSERT_SUBREG node? Is it a chain? No, insert_subreg returns a value: v1 = insert_subreg v2, v3, idx v1 and v2 will have the same type, e.g. i16, and v3 must have a sub- register type, e.g. i8. > Can I use to set a superreg of i16 type with two i8 values, and use > the supperreg as

On Oct 15, 2008, at 5:29 AM, sanjiv gupta wrote: > On Tue, 2008-10-14 at 10:19 -0700, Evan Cheng wrote: >> You need to specify sub-register == super-register, idx relationship. >> See X86RegisterInfo.td: >> >> def x86_subreg_8bit : PatLeaf<(i32 1)>; >> def x86_subreg_16bit : PatLeaf<(i32 2)>; >> def x86_subreg_32bit : PatLeaf<(i32

On Jul 17, 2009, at 7:57 AM, David Greene wrote: > In LiveIntervals::processImplicitDefs() we have this: > > for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(Reg), > UE = mri_->use_end(); UI != UE; ) { > MachineOperand &RMO = UI.getOperand(); > MachineInstr *RMI = &*UI; > ++UI; > MachineBasicBlock *RMBB

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>

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]

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>,

On 4/12/2018 8:01 AM, Dominique Torette via llvm-dev wrote: > > But there is one small issue in the inference of RegisterClass of the > implicitly defined register. > > As shown below, the %vreg6<def> is implicitly defined as FPUabRegisterClass. > > This register class accepts the v2f32 type, but for others addressing > mode context this register should be

Hi, I'm implementing the built_vector as an IMPLICIT_DEF followed by INSERT_SUBREGs. This approach is the one of the SPARC architecture. def : Pat<(build_vector (f32 fpimm:$a1), (f32 fpimm:$a2)), (INSERT_SUBREG(INSERT_SUBREG (v2f32 (IMPLICIT_DEF)), (i32 (COPY_TO_REGCLASS (MOVSUTO_A_iSLo (bitcast_fpimm_to_i32 f32:$a1)), FPUaOffsetClass)), A_UNIT_PART),

On Wed, 2008-10-15 at 10:08 -0700, Evan Cheng wrote: > On Oct 15, 2008, at 5:29 AM, sanjiv gupta wrote: > > > On Tue, 2008-10-14 at 10:19 -0700, Evan Cheng wrote: > >> You need to specify sub-register == super-register, idx relationship. > >> See X86RegisterInfo.td: > >> > >> def x86_subreg_8bit : PatLeaf<(i32 1)>; > >> def

Can someone explain where things like IMPLICIT_DEF_FR64 come from? I believe something is noticing a use before def and inserting some kind of bogus code to compensate. The machine instructions look like this (x86): %reg1069<def> = IMPLICIT_DEF_FR64 FsMOVLPDmr %reg0, 1, %reg0, 0, %reg1069 This is no good -- it stores to zero. Thanks. -Dave

On Wednesday 23 January 2008 02:01, Evan Cheng wrote: > > Can you explain the basic mechanics of the live interval splitting > > code? > It's splitting live intervals that span multiple basic blocks. That > is, when an interval is spilled, it introduce a single reload per > basic block and retarget all the uses to use the result of the single > reload. It does not

On Feb 20, 2008, at 12:25 PM, David Greene wrote: > On Wednesday 20 February 2008 14:14, David Greene wrote: > >> I discovered this through an assert I put into some of my own >> code. I want >> to know if that assert is bogus or if there's a bug here. > > A little more information: the assert checks that after coalescing > two nodes, > all subregister

On Wednesday 20 February 2008 14:14, David Greene wrote: > I discovered this through an assert I put into some of my own code. I want > to know if that assert is bogus or if there's a bug here. A little more information: the assert checks that after coalescing two nodes, all subregister live intervals for the register coaelsced to now interfere with whatever the eliminated live

On Wednesday 20 February 2008 07:00:28 pm Evan Cheng wrote: > > In other words, after coalescing, should it be the case that > > subregister > > intervals contain at least all of the range information that was > > contained > > in any eliminated intervals when those eliminated intervals were > > coalesced > > to the subregister's superregister? >

Guys, I think I figure out the way that the current LLVM allocators are handling IMPLICIT_DEF's. One question more: why are you adding null length intervals to IMPLICIT_DEF instructions? If they were non-null, I think the code to handle them would be more homogeneous, e.g a traversal of the intervals during register allocation would already reveal virtuals defined implicitly. best,