similar to: [LLVMdev] [LLVMDev] Reserved Registers

Displaying 20 results from an estimated 900 matches similar to: "[LLVMdev] [LLVMDev] Reserved Registers"

2010 Nov 08
0
[LLVMdev] [LLVMDev] Register Allocation and copy instructions
On Nov 8, 2010, at 12:04 PM, Jeff Kunkel wrote: > 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
2014 Dec 21
5
[LLVMdev] [RFC] [X86] Mov to push transformation in x86-32 call sequences
Hello all, In r223757 I've committed a patch that performs, for the 32-bit x86 calling convention, the transformation of MOV instructions that push function arguments onto the stack into actual PUSH instructions. For example, it will transform this: subl $16, %esp movl $4, 12(%esp) movl $3, 8(%esp) movl $2, 4(%esp) movl $1, (%esp) calll _func addl $16, %esp
2011 Jan 20
4
[LLVMdev] [LLVMDev] Live Intervals and Finding the next usage
I have a live interval, and I would like to find out what SlotIndex the next use the register will occur? Is there any way to map a live interval back into instructions or SlotIndexes or blocks used by? - Thanks Jeff Kunkel -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20110120/fd429dbd/attachment.html>
2010 Nov 08
2
[LLVMdev] [LLVMDev] Register Allocation and copy instructions
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
2010 Sep 28
2
[LLVMdev] [LLVMDev] Profiling information
How do I find the profiling or run time information for machine basic blocks from a machine function? There are quite a few optimization that may be preformed with this information, when it exists. Thanks, Jeff Kunkel
2010 Oct 09
3
[LLVMdev] [LLVMDev] Does LLVM have a random number generator?
Hello, does LLVM already have a Random Number Generator built into it's library somewhere? I know code generation is suppose to be deterministic, but when producing a random number can be deterministic if the random number generator is also deterministic. - Thanks - Jeff Kunkel
2010 Oct 05
3
[LLVMdev] [LLVMDev] Phi elimination: Who does what
Aye, between all current register allocators the 'AU.addRequiredID(PHIEliminationID);' will cause phi's to be eliminated to copies, but this misses the point of my question. What I am asking, is how does stack know that the value of the variable which the resulting value of the phi is currently allocated at. For instance take the instruction: Machine Basic Block (mbb) 12 reg16666 =
2010 Sep 03
4
[LLVMdev] [LLVMDev] [Question] How do I get the number of machine registers.
How do I get the total number of machine registers? I have currently a MachineFunction and some derivatives. How are the machine registers ordered internally? Can I index them off of a zero based array or do I have to create a map to have them be zero based? Thanks, Jeff Kunkel -------------- next part -------------- An HTML attachment was scrubbed... URL:
2010 Sep 02
5
[LLVMdev] [LLVMDev] [Modeling] About the structure of my allocator
I need to model my registers for my allocator. I need to identify the super-register and the sub-register conflicts. Something like: For each set of registers R in the set of aligned registers defined by the input request virtual register alpha. Now each register block r in R can have zero, one, or more registers defined in the block started at the aligned size and ending at the aligned size plus
2010 Oct 07
2
[LLVMdev] [LLVMDev] Has anyone written this?
It would go something like like the code below. The goal would be to turn the basic blocks which the graph looks like "...->x->y->..." where the instructions of x and y could live in the same basic block without a jump or fall through in between. bool runOnMachineFunction(MachineFunction &mf) { BitVector seen( mf.size() ); for( unsigned i = 0, e = mf.size();
2010 Sep 03
2
[LLVMdev] [LLVMDev] [Question] How do I get the number of machine registers.
It's not too much of a problem then. I can make a DenseMap between the registers and my registers. It's just one more intermediate step for a lookup. I wish to mimic all the of the registers on the machine with my std::vector<RegisterInfo> RegisterIndexes; vector. Then when a register is used I can assign it easily. I know about alias register and those are taken care of ever so
2010 Nov 02
4
[LLVMdev] [LLVMDev] Long compile times
I'm just running VS 10 in debug mode. In a step by step set up: 1. I download the svn 2. I make my changes 3. I compile the libraries 4. I make changes to the code within my project 5. I compile my code, and I re-link llc with my changed files. 6. I repeat 4,5, and 6 until it finally works. - Jeff Kunkel On Tue, Nov 2, 2010 at 1:21 PM, Óscar Fuentes <ofv at wanadoo.es> wrote: >
2010 Sep 03
2
[LLVMdev] [LLVMDev] [Modeling] About the structure of my allocator
It is at the end allowing for oddities like debug info and multiple branches. You might want to look at AnalyzeBranch. On Sep 2, 2010, at 4:19 PMPDT, Jeff Kunkel wrote: > Is there any way to tell where in the Instruction list, the branch > to the other MachineBasicBlock happens? I know in the BasicBlock had > a nice api for it. > > Thanks, > Jeff Kunkel > > On Thu,
2010 Sep 02
2
[LLVMdev] [LLVMDev] [Modeling] About the structure of my allocator
On Sep 2, 2010, at 2:44 PMPDT, Jeff Kunkel wrote: > I need to track which MachineBasicBlocks branch into other > MachineBasicBlocks. How do I do it? Look at the Predecessor/Successor lists, which are target-independent > I see a MachineOperand can hold a MachineBasicBlock*. Does this mean > the instruction may branch to the MachineBasicBlock, or can it be > something like an
2010 Sep 29
0
[LLVMdev] [LLVMDev] Profiling information
Bump: Does profiling / run time information exist when dealing with machine basic blocks? Thanks, Jeff Kunkel On Tue, Sep 28, 2010 at 9:51 AM, Jeff Kunkel <jdkunk3 at gmail.com> wrote: > How do I find the profiling or run time information for machine basic > blocks from a machine function? There are quite a few optimization > that may be preformed with this information, when it
2011 Jan 20
0
[LLVMdev] [LLVMDev] Live Intervals and Finding the next usage
I am looking for the slot index of a register around the given slot index Min. Is there a better way than the linear search: ... findDefUsesAroundIndex( LiveInterval* li, SlotIndex Min ) ... for( MachineOperand * mo = MRI->getRegUseDefListHead(li->reg); mo; mo = mo->getNextOperandForReg() ) { SlotIndex si = SI->getInstructionIndex( use.getOperand().getParent() ); if(
2010 Oct 05
2
[LLVMdev] [LLVMDev] Phi elimination: Who does what
The allocator you are building, is it the Hack's and Goos's polynomial time algorithm? On Tue, Oct 5, 2010 at 7:14 PM, Cameron Zwarich <zwarich at apple.com> wrote: > There is nothing that currently handles this properly, as far as I know. If you have a phi > > c = phi(a, b) > > where a, b and c are all assigned distinct stack slots, then copies must be inserted in
2010 Oct 05
2
[LLVMdev] [LLVMDev] Phi elimination: Who does what
When doing phi elimination, does one have to communicate with the stack space at all? The problem I see is two distinctly different registers may have two distinctly different stack spaces. When these registers are combined in a phi, the values the registers point to needs to be moved, combined, or otherwise taken care of. I understand this is the job of the stack space colorer, but when doing phi
2010 Nov 03
2
[LLVMdev] Static Profiling Algorithms in LLVM
You said it was expensive, but if you had to put a big-o estimate on it, what would it be? -Thanks Jeff Kunkel On Tue, Nov 2, 2010 at 8:54 PM, Andrei Alvares <logytech at gmail.com> wrote: > Hello Jeff, > > On Tue, Nov 2, 2010 at 9:17 PM, Jeff Kunkel <jdkunk3 at gmail.com> wrote: > > My god! I would love a branch predictor! It would simplify many aspects > of >
2011 Feb 07
1
Unusual slowing of R matrix multiplication version 2.12.1 (2010-10-15) vs 2.12.0
R Version 2.12.1 (2010-10-15) vs 2.12.0 has slowed down 8 fold for dual core and 17 fold for dual-core-dual-processor Macs. I have checked this result on 3 different macs using the following R-script: Using Version 2.12.0 on a dual core dual processor Mac: > source("http://www.bio.umass.edu/biology/kunkel/pub/R/CuriousResult.R") matrix multiplication 43.543 1.308 14.788