similar to: Generating a custom opcode from an LLVM intrinsic

Craig, thanks for the quick response. That helps a lot. I had no clue they were buried in there, though I guess I should have looked harder -- the hex should have given me a clue, perhaps! For the sake of my own edification (and not taking up too much of your time) I will try to generate it myself. I've found the definition of the "I" class at line 358 of

ASM is the text output you want printed in a textual listing of the assembly. The curly braces you see in some text strings like "adcx{l}\t{$src, $dst|$dst, $src}" are there to provide different operand orders for at&t syntax vs intel syntax. Anything after $ matches the name in the outs/in part of the instruction. IIC_SSE_PREFETCH is part of the scheduler system to provide

Here's a couple examples for mapping an intrinsic to an X86 instruction from X86InstrInfo.td. If you look for int_x86_* in any X86Instr*.td you can find others. let Predicates = [HasCLFLUSHOPT], SchedRW = [WriteLoad] in def CLFLUSHOPT : I<0xAE, MRM7m, (outs), (ins i8mem:$src), "clflushopt\t$src", [(int_x86_clflushopt addr:$src)],

Great info -- all of this has been incredibly useful. Do you have any links to the documentation from this, or does it just come from your experiential knowledge? FYI, I achieved what I set out to achieve when I wrote this email. I'm moving on to a more complex goal now, but the original question was answered completely, in my opinion. This was the key line: def CACHEOP : I<0x06, RawFrm,

Hi all. tl;dr: I would like to add a long x86 instruction which doesn't conform to any existing format that I know; I'm not sure where to start. I am attempting to add an instruction into X86, to be simulated in gem5. I've already added a simple, opcode-only instruction which I can successfully decode and run in gem5, so I am roughly familiar with .td files and how backends are built

Whoops - sorry for the confusion. n would be set in stone beforehand. I basically meant to indicate that we'd either be looking at a 32 bit or 64 bit system, ie 4 byte or 8 byte addresses. On Tue, Mar 20, 2018, 1:07 PM Craig Topper <craig.topper at gmail.com> wrote: > Hi Gus, > > When you say "n byte destination" you mean you want to encode an n byte > address as

0x0f 0x6f 0xc8 And 0x0f 0x7f 0xc1 Should both be movq % mm0, % mm1. (AT&T) However, llvm 3.4 at least does not recognise the second variant as being a valid instruction. We are currently compiling up latest src incase it has been fixed. If not, could someone take a look or recommend how to fix? Lee -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi Gus, When you say "n byte destination" you mean you want to encode an n byte address as a constant within the instruction? That would mean you couldn't encode an address that comes from a register. ~Craig On Tue, Mar 20, 2018 at 9:48 AM, Gus Smith via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Hi all. > > tl;dr: I would like to add a long x86 instruction

Hi, This patch fixes outs/ins of MOV16mr instruction of X86. Thanks. diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td index e9a0431..f5b2064 100644 --- a/lib/Target/X86/X86InstrInfo.td +++ b/lib/Target/X86/X86InstrInfo.td @@ -1412,7 +1412,7 @@ let SchedRW = [WriteStore] in { def MOV8mr : I<0x88, MRMDestMem, (outs), (ins i8mem :$dst, GR8 :$src),

That wasn't the part that confused me. What confused me was what you expected to be encoded into the instruction. Your math indicated that you multiple n by 3 and added 1 to it to get your 13 bytes. So that means you intend to use 4 bytes to store an address in 32 bits which implied to me that you intended to have a fixed address encoded. But what if the address in in a register as would often

I have this code, which works fine on MacOS and Linux hosts: const char *target_specific_cpu_args; const char *target_specific_features; if (g->is_native_target) { target_specific_cpu_args = ZigLLVMGetHostCPUName(); target_specific_features = ZigLLVMGetNativeFeatures(); } else { target_specific_cpu_args = ""; target_specific_features =

I suspect that there are 2 issues here: * I have incorrect alignment somewhere * MSVC / .pdb / CodeView debugging is not working correctly. I think the latter would help solve the former. I will send out a new email later talking about the issues I'm having debugging llvm-generated binaries with MSVC. On Sat, Sep 30, 2017 at 3:33 PM, Andrew Kelley <superjoe30 at gmail.com> wrote:

Hi all -- first time poster, hoping that this is going to the right list. Also a complete LLVM newbie, so please correct any glaring errors in my understanding. I am an architecture researcher at Penn State working on Processing in Memory (PIM) architectures. Currently, I plan to use LLVM to detect and replace groups of instructions which can be accelerated in memory. Once a group of

I figured it out. I was using this implementation of __chkstk from compiler-rt: DEFINE_COMPILERRT_FUNCTION(___chkstk) push %rcx cmp $0x1000,%rax lea 16(%rsp),%rcx // rsp before calling this routine -> rcx jb 1f 2: sub $0x1000,%rcx test %rcx,(%rcx) sub $0x1000,%rax cmp $0x1000,%rax ja 2b 1:

Hi all, I'm trying to simulate an extended x86 architecture on gem5 with several new instructions. My hardware setup is done and now I'd like llvm to accept the existence of the new instruction passed in inline assembly and output the correct opcode and registers. I chose the two-byte opcode 0x0F 0x7A and I would like the instruction to have the same operands and return values as CVTPS2PI

tl;dr, I'd like to add my own instruction, but I'm running into problems due to my lack of x86 encoding/decoding understanding. Hello all. Currently, I'm working on adding my own x86 instruction. I have done this once before; the basic process I used was: 1. Find an unused opcode, e.g. 0xF1 in this table: http://ref.x86asm.net/coder32.html 2. Insert an instruction into

Hi All, I'm trying to compile clang+llvm on my desktop with cross-compiler to be able to work with llvm commands in ubuntu-arm image whithin gem5. If anybody has done this before I'd be so thankful to know the exact process and commands. I tried to configure llvm as follows but I couldn't get the arm-arm version correctly. To sum up, I need to cross-compile llvm for ARM to work in

Hi, I'm trying to implement a new backend for an embedded CISC processor. Therefore I thought that it makes sense to take X86 target as a basis, to save some time. But when I look into the X86InstrInfo.td, I have a very strong feeling that it is one of the most complex instruction set descriptions compared to other targets. I can imagine that this is due to the complexity of X86's

Purpose: I implemented a pass on LLVM backend that changes the output format of *ARM* assembly/binary (e.g add a jump at the end of each basic block to eliminate fall through). By calling: llc -march=arm somefile.bc it generates expected arm assembly/binary that runs properly on arm gnu linux (I use qemu-arm and gem5 to simulate it). Now I want to do the same thing on standard c library, but

Hi Silky, If I got correctly, you seem to be trying to run a bare-metal image on your model, but you compile with linux-gnueabi GCC. I don't know if that will make a difference, but I'd try to use none-eabi GCC toolchain and set the -target armv7a-none-eabi just in case. On 10 March 2013 00:26, Silky Arora <silkyar at umich.edu> wrote: > Most of the search results talk about