similar to: Is the correct behavior of getelementptr i192* for opt + llc -march=aarch64?

On 10 November 2016 at 04:29, MITSUNARI Shigeo via llvm-dev <llvm-dev at lists.llvm.org> wrote: >>Is your default target aarch64? Otherwise opt may be assuming a different >>target which might explain the difference. > > No, My target is x86-64, x86, arm, aarch64, ..., then I'll avoid using i192* and datalayout. I believe Tom's point was about the line: % opt-3.8

For 64-bit X86 code we have had good success with using up-to 128-bit integers (this includes say 36-bit or even 2-bit integers). On Mon, Feb 2, 2015 at 4:03 PM, Alejandro Velasco <gollumdelperdiguero at gmail.com> wrote: > I asked a similar question last year here. Operations on types iN with no > direct translation into one assembly instruction seem to be translated into >

Hello all! I'm working on a library with bignum support, and I wanted to try LLVM as an apparently simpler and more portable system to my current design (a Haskell script which spits out mixed C and assembly). Porting the script to use the LLVM bindings instead of the current hack was pretty easy. But I have a few remaining questions: (1) Are bignums exposed to any higher-level

Hi everyone! Here, I have a question and am curious about i128. I want to know how the LLVM handle i128, because many compiler backend doesn't support i128 directly. So I am very curious and want to how the llvm handle this situation? Besides i128, such as i256, i512, even i24? Thanks. Best Regards Wu Zhao -------------- next part -------------- An HTML attachment was scrubbed...

Hello everybody, I have stumbled upon a test case (the attached module is a slightly reduced version) that shows extremely reduced performance on linux compared to windows when executed using LLVM's JIT. We narrowed the problem down to the actual code being generated, the source IR on both systems is the same. Try compiling the attached module: llc -O3 -filetype=asm -o BAD.s BAD.ll Under

On Sep 29, 2010, at 8:35 AMPDT, Ralf Karrenberg wrote: > Hello everybody, > > I have stumbled upon a test case (the attached module is a slightly > reduced version) that shows extremely reduced performance on linux > compared to windows when executed using LLVM's JIT. > > We narrowed the problem down to the actual code being generated, the > source IR on both systems

I'm trying to use LLVM to create compiler-rt.o on Windows. I use this command from the compiler-rt project: [nix-shell:~/downloads/llvm-project/compiler-rt]$ clang -nostdlib -S -emit-llvm lib/builtins/udivti3.c -g -target x86_64-windows -DCRT_HAS_128BIT The resulting LLVM IR is: ================================================================= ; ModuleID = 'lib/builtins/udivti3.c'

Most probably you need to properly specify the calling convention the backend is using for calling the runtime functions. Or implement the stub for udivti3 that performs the necessary argument lifting. I guess there is no standard ABI document describing the intended calling convention here, so I'd just do what mingw64 does here and make everything here compatible. On Thu, Apr 26, 2018 at

On Thu, Apr 26, 2018 at 3:44 AM, Anton Korobeynikov <anton at korobeynikov.info > wrote: > Most probably you need to properly specify the calling convention the > backend is using for calling the runtime functions. Thanks for the tip. Can you be more specific? Are you suggesting there is some config parameter I can set before running TargetMachineEmitToFile? Do you know what

I think from the C compiler's point of view, it is going to want it to work for any size above an i64, i.e. all the way up to an i128 so that if the user of the C compiler does this computation with __uint128_t's then it will Do The Right Thing TM. Basically, you want unsigned long a, b, c, d; .... const __uint128_t u = (__uint128_t) a + b; const unsigned long v = u >> 64; const

> Yeah I had a think about it, and I think intrinsics are the wrong way > to do it. So I'd say you are likely right. For this to work well, the way the code generators handle flags will need to be improved: currently it is suboptimal, in fact kind of a hack. Ciao, Duncan.

Hello! I noticed that in some cases clang generates sequence of AND+TST instructions: For example: AND x3, x2, x1 TST x2, x1 I think these instructions should be merged to one: ANDS x3, x2, x1 ( because TST <Xn>, <Xm> is alias for ANDS XZR, <Xn>, <Xm> -

Hello, Does anyone know of any precedent for handling i128 in the calling convention on x86-32? I'm trying to write a testcase that returns an i128 value, and LLVM currently has only two 32-bit GPRs designated for returning integer values on x86-32. Dan

I am seeing i128 from llvm-gcc on Alpha.  I know the calling convention for them, they are split into two registers, but I don't know if that should be handled in the frontend or the backend.  I would just as soon do it in the backend, but I didn't see any support in the new calling convention work for automatically splitting an argument into multiple registers. Is the backend the best

Yeah I had a think about it, and I think intrinsics are the wrong way to do it. So I'd say you are likely right. Bill. On 13 June 2010 04:33, Alistair Lynn <arplynn at gmail.com> wrote: > Hi Bill- > > I think, ideally, the backend would be able to match arbitrary-precision arithmetic to add-with-carry or subtract-with-borrow through i65/i33. That would remove the need for the

I was able to get the loop to increment from -999 to 0 using IR directly. That got rid of the cmpq. The carry i was after was able to be obtained using the intrinsic @llvm.uadd.with.overflow.i64, however there is no way to add with carry and have it realise that the resulting *carry out* cannot exceed 1. It actually writes the carry to a byte, and then uses logical operations on it, which slows

Hello everybody, I'm seeing LLVM (v 3.1) abort when trying to generate code that multiplies or divides 128-bit integers on x86-32. Here is a complete example function: define %jl_value_t* @foo564(%jl_value_t*, %jl_value_t**, i32) { top: %3 = load %jl_value_t** %1, align 4, !dbg !5139 %4 = getelementptr inbounds %jl_value_t* %3, i32 0, i32 0, !dbg !5139 %5 = getelementptr %jl_value_t**

On 12 June 2010 00:51, Eli Friedman <eli.friedman at gmail.com> wrote: > On Fri, Jun 11, 2010 at 3:28 PM, Bill Hart <goodwillhart at googlemail.com> wrote: >> Hi Eli, >> >> On 11 June 2010 22:44, Eli Friedman <eli.friedman at gmail.com> wrote: >>> On Fri, Jun 11, 2010 at 10:37 AM, Bill Hart <goodwillhart at googlemail.com> wrote:

On Mon, Nov 30, 2015 at 7:24 PM Gao, Yunzhong < yunzhong_gao at playstation.sony.com> wrote: > According to > http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html, > "The high-order double-precision value (the one that comes first in > storage) must have the larger magnitude." > > So the order of the two doubles in your fp128 is not affected by the

In both LLVM 2.9 and the current svn head, I get the following error when running llc % llc < fxp2.ll LLVM ERROR: Cannot select: 0xa5302b0: glue = carry_false [ID=7] on this code: target triple = "i386-pc-linux-gnu" define i32 @fxpadd(i32 %cl) { entry: %0 = zext i32 %cl to i128 %1 = zext i32 %cl to i128 %2 = add i128 %1, %0 br label %L1001510 L1001510: