search for: saturates

...from? It doesn't make sense to >>> saturate to a non-float dtype. I'd go ahead and just >>> assert(!i->saturate) in the int dtype cases. >>> >>> One does wonder what the hw does if the float doesn't fit in the >>> destination... whether it saturates or not. I don't hugely care >>> though. >> Actually i can't remember why that was added in the first place, i'll go >> ahead and follow your advice here. > Oh wait... this was to support saturating an array access into a u16... > > const int sat =...

Hi all, The patches linked below introduce a new family of intrinsics, for integer saturation: @llvm.usat, and @llvm.ssat (unsigned/signed). Quoting the added documentation: %r = call i32 @llvm.ssat.i32(i32 %x, i32 %n) is equivalent to the expression min(max(x, -2^(n-1)), 2^(n-1)-1), itself implementable as the following IR: %min_sint_n = i32 ... ; the min. signed integer of

> One thing I've noticed so far in the filter_mem2 code is the calls to > SATURATE(x, 805306368). 805306368 is 0x30000000. I was expecting that > to be on a bit boundary, say 0x3fffffff? In which case the arithmetic > saturation logic could be used. I don't think it would make that big of a difference, since the saturation is outside of the inner loop. If it's that

...> Where did this saturate stuff come from? It doesn't make sense to > saturate to a non-float dtype. I'd go ahead and just > assert(!i->saturate) in the int dtype cases. > > One does wonder what the hw does if the float doesn't fit in the > destination... whether it saturates or not. I don't hugely care > though. Actually i can't remember why that was added in the first place, i'll go ahead and follow your advice here. >> + else >> + res.data.u16 = util_iround(imm0.reg.data.f32); >> + break; >>...

On Fri, Jun 17, 2011 at 3:08 PM, Evan Cheng <evan.cheng at apple.com> wrote: > Hi all, > > I'm proposing integer saturation intrinsics. > > def int_ssat : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, llvm_i32_ty]>; > def int_usat : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, llvm_i32_ty]>; > > The first operand is the integer value

Hi all, I'm proposing integer saturation intrinsics. def int_ssat : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, llvm_i32_ty]>; def int_usat : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, llvm_i32_ty]>; The first operand is the integer value being saturated, and second is the saturation bit position. For scalar integer types, the semantics are: int_ssat: x <

> -----Original Message----- > From: r-help-bounces at stat.math.ethz.ch > [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of David Firth > Sent: Tuesday, March 16, 2004 1:12 PM > To: Paul Johnson > Cc: r-help at r-project.org > Subject: Re: [R] glm questions > > > Dear Paul > > Here are some attempts at your questions. I hope it's of some help.

Hi all, While tinkering with saturation instructions, I hit problems with the cost model calculations. The loop vectorizer cost model accumulates the individual TTI cost model of each instruction. For saturating arithmetic, this is a gross overestimate, since you have 2 sexts (inputs), 2 icmps + 2 selects (for the saturation), and a truncate (output); these all fold alway. With an intrinsic,

On Jun 17, 2011, at 3:42 PM, Eli Friedman wrote: > On Fri, Jun 17, 2011 at 3:08 PM, Evan Cheng <evan.cheng at apple.com> wrote: >> Hi all, >> >> I'm proposing integer saturation intrinsics. >> >> def int_ssat : Intrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, llvm_i32_ty]>; >> def int_usat : Intrinsic<[llvm_anyint_ty],

Hello all again, take 2. Over in D68651 I would like to make code that attempt to saturate an value (using higher bitwidth integers) use a saturating intrinsic instead. Something like this: https://godbolt.org/z/9knBnP As can be seen, the unsigned cases are already being matched to llvm.uadd.sat intrinsics. I am hoping to extend that to the signed cases. This has numerous benefits including

Hi, I just started to examine the DIV32_16 function (Blackfin ASM version), and wondered why the return value of the function inside 'fixed_bfin.h' is of type 'spx_word16_t', but the local variable 'res' which is returned by this function is of type 'spx_word32_t'. Is this a trick of optimization or a bug? (Same question for PDIV32_16 and MAX16, too!) best

...rand. As with regular left shift instructions, the second operand is an unsigned quantity and must be less than the integer bitwidth. If the true result of the operation (given infinite precision) lies outside of the maximum or minimum representable value of the signed/unsigned integer, the result saturates to the maximum or minimum depending on the sign of the shifted value. These are useful for implementing the Embedded-C fixed-point arithmetic support in Clang, as previously detailed and discussed here: http://lists.llvm.org/pipermail/llvm-dev/2018-August/125433.html http://lists.llvm.org/pipermai...

On Thu, Jan 15, 2015 at 2:33 AM, David Chisnall <David.Chisnall at cl.cam.ac.uk > wrote: > A couple of questions: > > 1) Should this really be an intrinsic and not a flag on add? The add > instruction already allows overflow to be either undefined or defined to > wrap. Making it defined to saturate seems a natural extension. > I don't think this should be a flag on

...gt;>>> saturate to a non-float dtype. I'd go ahead and just >>>>> assert(!i->saturate) in the int dtype cases. >>>>> >>>>> One does wonder what the hw does if the float doesn't fit in the >>>>> destination... whether it saturates or not. I don't hugely care >>>>> though. >>>> Actually i can't remember why that was added in the first place, i'll go >>>> ahead and follow your advice here. >>> Oh wait... this was to support saturating an array access into a u16... &gt...

If we were to create a new type down the line, I think the main features that would distinguish them from other types are the arbitrary width and scale. Saturation can be handled through instructions since saturation really only takes effect after an operation and doesn’t really describe anything about the bits in the resulting type. Signage can similarly be managed through operations and would be

Folding for conversions: F32->(U{16/32}, S{16/32}) and (U{16/32}, {S16/32})->F32 Signed-off-by: Tobias Klausmann <tobias.johannes.klausmann at mni.thm.de> --- .../drivers/nouveau/codegen/nv50_ir_peephole.cpp | 109 +++++++++++++++++++++ 1 file changed, 109 insertions(+) diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp

Hi, I tried to figure out what the problem is -- but it seems to be totally different from what I expected. My status at the moment is: - computing results for "generic" and "Blackfin ASM" versions of the DIV32_16 function are the same, there is no "algorithmic bug" - Instead, there seems some sort of memory corruption: When I comment out the DIV32_16 function

> Quoting Stephane Lesage <stephane.lesage at ateis-international.com>: > > Is this a bug ? Is it possible to fix it ? > > (I use version speex 1.2beta2, because newer versions just > don't work > > on my > > platform) > > This is probable the cause. 1.2beta2 was the first release to > include the resampler and it had many bugs. I suggest trying

Frank Lorenz a ?crit : > And yes, the same "overflow" happens even when I disable Blackfin ASM > optimizations. Indeed, that shouldn't happen. Just to make sure I understand, so far there's two problems: 1) DIV32_16() in Blackfin assembly causes problems 2) The resampler overflows When you fix/workaround those two, is the encoder/decoder working correctly or are there

Folding for conversions: F32->(U{16/32}, S{16/32}) and (U{16/32}, {S16/32})->F32 Signed-off-by: Tobias Klausmann <tobias.johannes.klausmann at mni.thm.de> --- V2: beat me, whip me, split out F64 .../drivers/nouveau/codegen/nv50_ir_peephole.cpp | 81 ++++++++++++++++++++++ 1 file changed, 81 insertions(+) diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp