similar to: [OpenCL] Implicit arithmetic conversion of INT_MIN to int vector type

I've found what appears to be a bug in instcombine. Specifically, the transformation of -(X/C) to X/(-C) is invalid if C == INT_MIN. Specifically, if I have > define i32 @foo(i32 %x) #0 { > entry: > %div = sdiv i32 %x, -2147483648 > %sub = sub nsw i32 0, %div > ret i32 %sub > } then opt -instcombine will produce > define i32 @foo(i32 %x) #0 { > entry: > %sub

I'm wondering if WRE Section 5.2 should be a little more explicit about misuse of integer values other than NA, 0, and 1 in LGLSXPs.? I'm thinking of this passage: > Logical values are sent as 0 (FALSE), 1 (TRUE) or INT_MIN = -2147483648 (NA, but only if NAOK is true), and the compiled code should return one of these three values. (Non-zero values other than INT_MIN are mapped to

> On Fri, 2017-10-20 at 14:01 +0000, brodie gaslam via R-devel wrote: > > I'm thinking of this passage: > > > > > Logical values are sent as 0 (FALSE), 1 (TRUE) or INT_MIN = > > > -2147483648 (NA, but only if NAOK is true), and the compiled code > > > should return one of these three values. (Non-zero values other > > > than INT_MIN are

Please start a new thread for a new topic and use a meaningful subject for sake of the archives and everyone trying to follow. Using your Int1, correcting your Int2 and using your Y (which goes to Jul not Aug as per the comment): library(zoo) > as.ts(with(merge.zoo(Int1, Int2, Y, fill = 0), pmax(Int1, Int2))) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1992

Hi guys! I have to compute something and i don't know what i'm doing wrong. my code is a bit complex, but imagine that is something like this: a = c(1,2,3,4) ia = length(a) x = seq(1,100,length=0.1) ib = length(x) int1 = numeric(ib) b = numeric(ib) for(j in 1:ia) { H = function(x) {sin(x + a[j])} for(i in 1:ib) { int = integrate(H, lower = 0, upper

On April 25, 2014 at 10:48:18 AM, Reid Kleckner (rnk at google.com) wrote: On Fri, Apr 25, 2014 at 10:19 AM, Filip Pizlo <fpizlo at apple.com> wrote: The sdiv operation in LLVM IR only makes sense for C and its very direct relatives.  The amount of control flow necessary to represent a safe division for any other language is ghastly.  (a/b) becomes something like (b != 0 ? ((a != INT_MIN ||

> We are permitted to turn 'sub nsw i32 %x, 1' into 'add nsw i32 %x, -1' nsw also has the same problem: sub nsw int_min, int_min is 0 but add nsw int_min, (-int_min) is poison -- Sanjoy

>>>>> Martin Maechler <maechler at lynne.stat.math.ethz.ch> >>>>> on Fri, 17 Apr 2015 15:49:35 +0200 writes: >>>>> Herv? Pag?s <hpages at fredhutch.org> >>>>> on Mon, 13 Apr 2015 23:36:14 -0700 writes: >> On 04/13/2015 11:32 PM, Martin Maechler wrote: >>> >>>> Hi,

Hi, I recently came across the following in __floatsidf in compiler-rt: __floatsidf(int a) { ... if (a < 0) { ... a = -a; In the case where a == INT_MIN, is this negation not undefined behaviour? AIUI this function is used for software emulation on targets that have no hardware floating point support. Perhaps there is an in-built assumption

Hi all, We noticed a lot of unnecessary ptrtoint instructions that stand in way of some of our optimizations; the code pattern looks like this: bb1: %int1 = ptrtoint %struct.s* %ptr1 to i64 bb2: %int2 = ptrtoint %struct.s* %ptr2 to i64 %bb3: %phi.node = phi i64 [ %int1, %bb1 ], [%int2, %bb2 ] %ptr = inttoptr i64 %phi.node to %struct.s* In short, the pattern above arises due to: 1.

On April 25, 2014 at 9:52:35 AM, Eric Christopher (echristo at gmail.com) wrote: Hi Michael, > I’d like to propose to extend LLVM IR intrinsics set, adding new ones for > safe-division. There are intrinsics for detecting overflow errors, like > sadd.with.overflow, and the intrinsics I’m proposing will augment this set. > > The new intrinsics will return a structure with two

Dear Sir/madam, I'm getting a problem with a R-code which calculate Fisher Information Matrix for Hybrid Censored Weibull Distribution. My problem is that: when I take weibull(scale=1,shape=2) { i.e shape>1} I got my desired result but when I take weibull(scale=1,shape=0.5) { i.e shape<1} it gives error : Error in integrate(int2, lower = 0, upper = t) : the integral is probably

On Oct 3, 2013, at 7:15 AM, Michele Scandale <michele.scandale at gmail.com> wrote: > On 10/03/2013 01:22 AM, Andrew Trick wrote: >> >> I’m not sure how to make sense of an NUW flag coming from a sub. >> >> NSW is just a misnomer for signed overflow. SCEV canonicalizes sub a,b to add a, (-b). Unfortunately, signed overflow is not the same thing for sub and

On April 25, 2014 at 1:44:37 PM, Reid Kleckner (rnk at google.com) wrote: Thanks for the writeup! It's very helpful. On Fri, Apr 25, 2014 at 11:49 AM, Filip Pizlo <fpizlo at apple.com> wrote: On April 25, 2014 at 10:48:18 AM, Reid Kleckner (rnk at google.com) wrote: On Fri, Apr 25, 2014 at 10:19 AM, Filip Pizlo <fpizlo at apple.com> wrote: The sdiv operation in LLVM IR only

On 10/03/2013 04:15 PM, Michele Scandale wrote: > On 10/03/2013 01:22 AM, Andrew Trick wrote: >> >> I’m not sure how to make sense of an NUW flag coming from a sub. >> >> NSW is just a misnomer for signed overflow. SCEV canonicalizes sub a,b to add a, (-b). Unfortunately, signed overflow is not the same thing for sub and add... >> >> sub nsw %a, %b != add nsw

Dear List: A few weeks ago I posted some questions regarding data simulation and received some very helpful comments, thank you. I have modified my code accordingly and have made some progress. However, I now am facing a new challenge along similar lines. I am attempting to simulate 250 datasets and then run the data through a linear model. I use rm() and gc() as I move along to clean up the

On 10/03/2013 01:22 AM, Andrew Trick wrote: > > I’m not sure how to make sense of an NUW flag coming from a sub. > > NSW is just a misnomer for signed overflow. SCEV canonicalizes sub a,b to add a, (-b). Unfortunately, signed overflow is not the same thing for sub and add... > > sub nsw %a, %b != add nsw %a, (-1 * %b) > > sub nsw i32, -1, INT_MIN is true. > > add

sscanf is sadly not safe (because it doesn't handle integer overflow correctly), and strto*l functions are a pain to use correctly. Therefore add some functions to hide the pain of parsing integers from the command line. The simpler uses of sscanf and strto*l are replaced. There are still a few where we are using advanced features of sscanf. --- docs/nbdkit-plugin.pod | 48

On Oct 1, 2013, at 6:45 AM, Michele Scandale <michele.scandale at gmail.com> wrote: > Hello to everybody, > > I'm working on some improvements on trip count computation with ScalarEvolution > analysis. > Considering the following test > > ;----------------------------------------------------------------------------; > define void @foo(i32 %a, i32 %b, i32 %s) #0

On 04/13/2015 11:32 PM, Martin Maechler wrote: > >> Hi, >> > as.integer("5000000000") >> [1] 2147483647 >> Warning message: >> inaccurate integer conversion in coercion > >> > as.integer("-5000000000") >> [1] NA >> Warning message: >> inaccurate integer conversion in coercion >