similar to: [LLVMdev] PTX backend do not support sitofp instruction?

> Does PTX backend support llvm sitofp instruction? Seems it doesn't support sitofp, search "Conversion to f32" in PTXInstrInfo.td. Regards, chenwj -- Wei-Ren Chen (陳韋任) Computer Systems Lab, Institute of Information Science, Academia Sinica, Taiwan (R.O.C.) Tel:886-2-2788-3799 #1667

Hello, As I understand, in LLVM IR it cannot be determined whether a register of type int is signed or unsigned. If one wants to convert an integer to a double, which instruction should be used:  "uitofp" or "sitofp" ? We track the values taken by all load instructions and we process them using a function. If the value is a pointer, we use int64 as the type of the function

When the uitofp and sitofp instructions convert e.g. from i64 to float, what rounding mode do they use? Answers in the form a patch to LangRef.html would be great! Thanks, Jay.

On Wed, Jul 24, 2013 at 4:03 AM, Jay Foad <jay.foad at gmail.com> wrote: > When the uitofp and sitofp instructions convert e.g. from i64 to > float, what rounding mode do they use? Answers in the form a patch to > LangRef.html would be great! The default rounding mode, just like every other floating-point operation. -Eli

[+CC Andy] Hi Elena, I don't have any fundamental issues with teaching SCEV about floating point types, but given this will be a major change, I think a high level roadmap should be discussed on llvm-dev before we start reviewing and committing changes. Here are some issues that I think are worth discussing: - Core motivation: why do we even care about optimizing floating point

Thanks so much for your feedback Simon. I am not sure that what I am proposing here is at odds with what you're referring to (here and in the PR you linked). The key difference AFAICT is that the pattern I am referring to is probably more aptly described as "reducing scalarization" than as "vectorization". The reason I say that is that the inputs are vectors and the output

Absolutely. We do it for scalars, so it would likely be a matter of just extending it. But that is one example. The issue of extracting elements, performing an operation on each element individually and then rebuilding the vector is likely more prevalent than that. At least I think that is the case, but I'll do some analysis to see if it is so or not. On Sat, Jan 11, 2020 at 6:15 PM Craig

The fptrunc instruction states "If the value cannot fit within the destination type, ty2, then the results are undefined." This is fine, but what about other floating-point operations that can overflow? For example, does 'mul double 1.0e300, 1.0e300' produce +infinity or is it undefined? I think LLVM should treat floating-point overflows consistently. On a similar note,

On Sat, Jun 21, 2008 at 4:24 PM, Nicolas Capens <nicolas at capens.net> wrote: > I seem to be unable to cast a vector of integers to a vector of floats > (uitofp [4 x i8] to [4 x float], to be exact). It hits an assert in > LegalizeDAG.cpp line 5433: "Unknown int value type". The Assembly Language > Reference Manual's definition of uitofp doesn't indicate that

On Mon, 31 Mar 2008, Jon Sargeant wrote: > The fptrunc instruction states "If the value cannot fit within the > destination type, ty2, then the results are undefined." This is fine, but > what about other floating-point operations that can overflow? For example, > does 'mul double 1.0e300, 1.0e300' produce +infinity or is it undefined? It is defined by IEEE to

Hi all, I seem to be unable to cast a vector of integers to a vector of floats (uitofp [4 x i8] to [4 x float], to be exact). It hits an assert in LegalizeDAG.cpp line 5433: "Unknown int value type". The Assembly Language Reference Manual's definition of uitofp doesn't indicate that this is unsupported, so it looks like a bug to me. I'm on an x86 system by the way. My

Hi, Lately we have come to realize how undef makes our life complicated.. Therefore in this email we propose to change the behavior of a few instruction to yield poison instead of undef in error cases. This follows the suggestion of Eli in https://reviews.llvm.org/D33654. Why is undef so bad? - I believe it's not possible to make newgvn correct with undef. See for example the discussion

Ulrich offered to do it instead since I expect he can get it done much faster than me. Instead I'm doing SIToFP and UIToFP. Ulrich said he wasn't going to be able to get to it for a couple of weeks, but that was a week or two ago. Ulrich? -----Original Message----- From: Cameron McInally <cameron.mcinally at nyu.edu> Sent: Tuesday, October 01, 2019 10:21 AM To: Kristof Beyls

On Mon, Nov 21, 2011 at 7:01 AM, Alberto Magni <alberto.magni86 at gmail.com>wrote: > Hi Justin, > > attached you find the patch for the integer max instruction. > The multiclass PTX_INTRINSIC_INT3 in file PTXIntrinsicInstrInfo.td > is almost an exact copy of PTX_INT3 in PTXInstrInfo.td, maybe > a modification of this class can be defined in a separate file. > I'm

On Mon, Nov 21, 2011 at 3:36 PM, Justin Holewinski <justin.holewinski at gmail.com> wrote: > On Mon, Nov 21, 2011 at 7:01 AM, Alberto Magni <alberto.magni86 at gmail.com> > wrote: >> >> Hi Justin, >> >> attached you find the patch for the integer max instruction. >> The multiclass PTX_INTRINSIC_INT3 in file PTXIntrinsicInstrInfo.td >> is almost

Dear Justin, I am trying to add the support for some OpenCL builtin functions to the PTX backend. The attached file represent the first stub of a patch for the fmax builtin function. The test case I am trying is the following: define ptx_device float @f(float %x, float %y) { entry: %z = call float @fmax(float %x, float %y) ret float %z } declare float @fmax(float, float) But at the moment

On Mon, Nov 21, 2011 at 11:45 AM, Alberto Magni <alberto.magni86 at gmail.com>wrote: > On Mon, Nov 21, 2011 at 3:36 PM, Justin Holewinski > <justin.holewinski at gmail.com> wrote: > > On Mon, Nov 21, 2011 at 7:01 AM, Alberto Magni < > alberto.magni86 at gmail.com> > > wrote: > >> > >> Hi Justin, > >> > >> attached you find

Hi, I'm working now on extending SCEV Analysis and adding FP support. At the beginning, I want to vectorize this loop: float fp_inc; float x = init; for (int i=0;i<N;i++){ A[i] = x; x += fp_inc; // Loop invariant variable or constant } In this loop "x" is a FP induction variable. But it is not the "primary" induction and loop trip count is still depends

On Mon, Nov 21, 2011 at 5:31 PM, Justin Holewinski <justin.holewinski at gmail.com> wrote: > On Mon, Nov 21, 2011 at 11:45 AM, Alberto Magni <alberto.magni86 at gmail.com> > wrote: >> >> On Mon, Nov 21, 2011 at 3:36 PM, Justin Holewinski >> <justin.holewinski at gmail.com> wrote: >> > On Mon, Nov 21, 2011 at 7:01 AM, Alberto Magni >> >

Alberto, The AMDIL backend solves your problem with intrinsic overloading this way: def int_AMDIL_mad : GCCBuiltin<"__amdil_mad">, TernaryIntFloat; Where TernaryIntFloat is defined as: class TernaryIntFloat : Intrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>, LLVMMatchType<0>, LLVMMatchType<0>], []>; This allows us to write a