similar to: [LLVMdev] How to specify that Src Reg and Dest Reg can't be the same in td?

Hi Wei-Ren, I don't think you can model it with Constraints in td files. You may try to put a regalloc hint in src and dst operands of the instructions you are interested. See getRawAllocationOrder(), ResolveRegAllocHint() and UpdateRegAllocHint() hooks in TargetRegisterInfo. ARM has good examples on how to implements them. Ivan On 13/07/2012 09:28, 陳韋任 (Wei-Ren Chen) wrote: > Hi

Hi all, I started to write an LLVM backend for custom CPU. I created XXXInstrInfo but there are some problems. I searched for it but I couldn't find anything. Can anyone help me? include "XXXInstrFormats.td" def simm16 : Operand<i32> { let DecoderMethod = "DecodeSimm16"; } def mem : Operand<i32> { let PrintMethod = "printMemOperand"; let

I am trying to understand how LLVM does code generation and I have a couple of questions. I am using LLVM 2.6. First, if I want to change the name of an instruction, all I need to do is to modify the XXXInstrInfo.td, right? Using Sparc as an example, if I wanted to output "mysra" instead of "sra", in SparcInstrInfo.td, I would write, defm SRA : F3_12<"mysra",

On Jan 1, 2010, at 12:51 PM, mmms1841 wrote: > I am trying to understand how LLVM does code generation and I have a couple of questions. > I am using LLVM 2.6. > > First, > if I want to change the name of an instruction, all I need to do is to modify the XXXInstrInfo.td, right? > Using Sparc as an example, if I wanted to output "mysra" instead of "sra",

Hi all, is it possible to define an instruction as always having a certain register as operand in XXXInstrInfo.td? I know I can do it defining a single-register register class, but I need that register also to be on a broader class for other operations (and it is not possible for a reg to be in several classes AFAIU). Thanks! Carlos

I am using LLVM 2.8 on Ubuntu 10.10. (new to both) I change name of instruction on XXXInstrInfo.td ( Sparc, X86 and XCore). I looked into XXXGenAsmWriter.inc and I have seen the new instruction name. But when I run llc for the three targets it prints out the old instruction name. For example in XCoreInstrInfo.td I change the name of one of the instruction let say "divs" to

On Sunday 03 January 2010 01:00, Chris Lattner wrote: > On Jan 1, 2010, at 12:51 PM, mmms1841 wrote: > > I am trying to understand how LLVM does code generation and I have a > > couple of questions. I am using LLVM 2.6. > > > > First, > > if I want to change the name of an instruction, all I need to do is to > > modify the XXXInstrInfo.td, right? Using Sparc

I've been unable to come up with the TableGen recipe to match a negated operand. My target asm syntax allows the following transform: FNEG r8, r5 MUL r6, r8, r9 to MUL r6, -r5, r9 Is there a Pattern<> syntax that would allow matching *any* opcode (or even some subset), not just MUL, with a FNEG'd operand? I expect I can define a PatFrag: def fneg_su : PatFrag<(ops

Hey all, I've found a bug in either the PBQP register allocator or in VirtRegRewriter. I'm observing this assertion in VirtRegRewriter::rewrite() fail: unsigned VirtReg = MO.getReg(); unsigned PhysReg = VRM->getPhys(VirtReg); ... assert(!MRI->isReserved(PhysReg) && "Reserved register assignment"); Indeed there is a case where

Hi all, I'm building a backend for a custom target, and I'm trying to figure out how to handle global and external target address with my architecture's call instructions. This arch. has 16-bit addresses into a segmented address space, and to do a direct call I need to set both an instruction counter (IC, 10 bits wide) and an instruction segment register (ISR, 6 bits wide). My CALL

Hi Quentin, > It sounds like you only need the earlyclobber description for the N, N > variant. > In other words, as long as you use different opcodes for widen-op NN and > widen-op WN, you model exactly what you want. > > What am I missing? > we are using different opcodes for widen-op NN and widen-op WN. My understanding is that not setting earlyclobber to the W, N

Hi, > 1.1) Please verify all above change(s) are OK? or I have modify some code? Parts will almost certainly have to change in future, but if it builds that's an excellent first step. > 1.2) In LLVM, can we proceed our development like as GCC i.e. incremental > approach? In case of yes, please provide me any reference. Incremental is definitely possible. I started out with

Hello, I'm getting a machine verifier error after introducing the earlyclobber constraint to some instructions where the src and dest regs can't be the same. The offending instruction pattern is this one: let canFoldAsLoad = 1, isReMaterializable = 1, Constraints = "@earlyclobber $dst" in def LDDWRdPtrQ : Inst<(outs DREGS:$dst), (ins memri:$src),

Thanks Jakob. I should have mentioned that earlier. :) When you see mismatched sizes on operands it's a fair bet that the subreg rewriting has gone wrong. I should have pulled that entirely out of the preg search loop in the previous example. Fixed version attached. - Lang. -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi all, I'm working on a target whose registers have equal-sized subregisters and all of those subregisters can be named (or the other way round: registers can be grouped into super registers). So for instance we've got 16 registers W (as in wide) W0..W15 and 32 registers N (as in narrow) N0..N31. This way, W0 is made by grouping N0 and N1, W1 is N2 and N3, W2 is N4 and N5, ..., W15 is

Thanks Lang, I'll try substPhysReg. I did try your latest code, and although it made the assembler errors go away, now some of my tests produce bad output when executed. I need to look into that some more... (I did change my "usedPregSet" to be ALL pregs used in the whole function, not just those in the current instruction, so the problem should not be the erroneous

On Dec 15, 2009, at 5:08 PM, David Greene wrote: > On Tuesday 15 December 2009 18:01, Jim Grosbach wrote: > >> For a usage example, I've included in the patch the modification to >> use the constraint for the STREX ARM instruction. > > Your example is: > > constraints = "@early $success" > > Why not spell it as: > > constraints =

Hi, I'd like to define a pseudo-instruction whose expansion will, as a side-effect, overwrite an input register's value: the pseudo-instruction ldw r1:r2, P to load 2 bytes from memory address P is to be expaneded to ld r1, P+ ld r2, P where "ld _, P+" is an instruction that loads a single byte from P, and post-increments P by one. How can I represent this behaviour in

Hi Joe, Le 11/05/2012 02:13, Joe Matarazzo a écrit : > I've been unable to come up with the TableGen recipe to match a > negated operand. My target asm syntax allows the following transform: > > FNEG r8, r5 > MUL r6, r8, r9 > > to > > MUL r6, -r5, r9 > > Is there a Pattern<> syntax that would allow matching *any* opcode (or > even some

On Jul 14, 2012, at 10:09 AM, Borja Ferrer <borja.ferav at gmail.com> wrote: > Hello, > > I'm getting a machine verifier error after introducing the earlyclobber constraint to some instructions where the src and dest regs can't be the same. The offending instruction pattern is this one: > > let canFoldAsLoad = 1, > isReMaterializable = 1, > Constraints =