similar to: [LLVMdev] llvm getDependency() for ICMP instructions is UNKNOWN

Hi, I'm having a problem with GVN removing a load instruction that I think is needed. Dump before GVN: *** IR Dump Before Global Value Numbering *** ; Function Attrs: minsize optsize define i16 @TEST__MAIN(i16 %argc.13.par, i16** %argv.14.par) #0 { %buf.17 = alloca [10 x i16], align 1 %_tmp30 = getelementptr inbounds [10 x i16], [10 x i16]* %buf.17, i16 0, i16 0, !dbg !22 call

Hi, It seems that opt thinks that the two pointers %_tmp2 = getelementptr [3 x i16], [3 x i16]* %a, i16 0, i64 1 and %_tmp4 = getelementptr [3 x i16], [3 x i16]* %a, i16 0, i16 1 does not alias? Is this intended or a bug? Details below: -------------- I found this when I ran opt on: define i16 @f () { %a = alloca [3 x i16] ; Write 98 at index 1 in the array. ; NB: using i64 as

Hi there, I was trying to see what kind of informations I can get on dependence/alias analysis from the trunk llvm, and stumbled upon two potencial problems. First of all, the most recent documentation I could find online <http://llvm.org/docs/AliasAnalysis.html> suggests the use of options not available on the code (like enabling globalsmodref-aa, or count-aa, for example). Is there a more

Hi, I have tried memory dependence analysis. I found that load could have def dependence on another load. How could this happen? And what does clobber dependence mean? Thanks a lot! Best, Linhai

hello, a friend of mine have this configuration: 10 x PC -- router/linux/rh8 -- ADSL Modem -- ISP let''s say that the bandwidth is: 5M and 800K he does dc++ and counter-strike, so let''s say the UP is full, and the ping from the counter server is 300ms, the server cut the connection, and no more game, the player is unhappy. The normal ping is 50ms. so he thinks to put some

Hi, I am writing an analysis pass for a custom processor. I get an unusual situation where the code generated for a BB is BB#23: derived from LLVM BB %sw.bb99 Live Ins: %vr2 %vr0 %vr1 %vr9 %vr3 %vr8 %vr4 %vr5 %vr6 Predecessors according to CFG: BB#22 %vr46<def> = LD_Iri %LV, -4; mem:LD4[FixedStack0] %vr7<def> = ADDri %vr9, 1 %vr47<def> = ADDri

Hello, I have a code similar to the following: program test integer i, j, N real B(10) call bar(N, 8) N = N+1 do i = 1, N B(i) = (i+5)/(i+3) enddo j = N/2 N = N+7 call IMPORTANT_F(B, N, i, j) end program and I am trying to use dependence

I'm attaching the .bc file. Note that my analysis pass is invoked after "-O1" and that's why the IR I included in the original email is optimized. -------------- next part -------------- A non-text attachment was scrubbed... Name: simple_loops_F2_4list.bc Type: application/octet-stream Size: 6384 bytes Desc: not available URL:

On Apr 13, 2009, at 12:01 PM, Anthony Danalis wrote: > I'm attaching the .bc file. Note that my analysis pass is invoked > after "-O1" and that's why the IR I included in the original email > is optimized. Hi Anthony, Sorry for the delay, things have been crazy lately. The MemDep API assumes that you will call getDependency() first, and then only call

before inlining all 20005 after inlining somewhere here changed made it NoAlias after Global Variable Optimizer 20014 20373 20255 20372 20254 before GVN 19993 20011 19991 20010 20030 It appears that TBAA metadata certainly changed after inlining and subsequent passes. I have attached the .bc file. I think I will try to dump out more TBAA metadata between passes. The method in

Thanks for quick reply Daniel, I tried to make a simple C testcase, but could not reproduce the same condition with output from Clang. I suppose I could modify the C code to make it look similar with TBAA's; I may be able to provide this by eod. > store %ptr above the load. My mistake; I was referring to the store $lcssa in bb2. Looking at the C source code, it should definitely alias

Thanks Daniel, I'll do a debug build of LLVM (I guess that'll teach me) and step through it as soon as I'll find a power outlet. I'm calling getDependency on the load instruction, and it returns the store instruction. Suspiciously enough, calling invalidateCachedPointerInfo on load->getPointerOperand() does not cause my AA pass to be called again when I use getDependency (or

On Mon, Apr 13, 2009 at 9:06 AM, Anthony Danalis <adanalis at eecs.utk.edu> wrote: > How can I use MemoryDependenceAnalysis (or any other analysis for that > matter) to gather that the instructions > j = N/2  (store i32 %11, i32* %j, align 4) > and > N = N+7  (store i32 %12, i32* %n, align 4) > are the ones that define the parameters "j" and "N"

On Apr 13, 2009, at 3:32 PM, Eli Friedman wrote: > On Mon, Apr 13, 2009 at 9:06 AM, Anthony Danalis <adanalis at eecs.utk.edu > > wrote: >> How can I use MemoryDependenceAnalysis (or any other analysis for >> that >> matter) to gather that the instructions >> j = N/2 (store i32 %11, i32* %j, align 4) >> and >> N = N+7 (store i32 %12, i32* %n,

On Apr 13, 2009, at 9:06 AM, Anthony Danalis wrote: > Hello, > > I have a code similar to the following: Hi Anthony, Can you please attach the .bc file for this? -Chris > > > program test > integer i, j, N > real B(10) > > call bar(N, 8) > N = N+1 > do i = 1, N > B(i) =

On Apr 25, 2009, at 5:05 PM, Chris Lattner wrote: > > On Apr 13, 2009, at 12:01 PM, Anthony Danalis wrote: > >> I'm attaching the .bc file. Note that my analysis pass is invoked >> after "-O1" and that's why the IR I included in the original email >> is optimized. > > Hi Anthony, > > Sorry for the delay, things have been crazy lately. >

On 08/07/2015 01:53 PM, Caldarale, Charles R wrote: >> From: llvm-dev [mailto:llvm-dev-bounces at lists.llvm.org] >> On Behalf Of Mikael Holmén via llvm-dev >> Subject: [llvm-dev] load instruction erroneously removed by GVN > >> But between the load and the alloca there is also >> call fastcc void @format_long(i16* %_tmp30, i16 10, i32 10), !dbg !22 >>

Howdy, I'm working on writing a dependence analyzer (rather like what LoopDependenceAnalysis wants to be, except a bit more general). While this is a problem of many parts, I'm currently focusing on finding pairs of memory references to test for dependence. Consider this contrived C code: double test2(int n, double *restrict A, double *restrict B, bool flag) { if (flag) { A[0] =

On Jul 22, 2009, at 1:37 PM, Jakub Staszak wrote: > Hello, > > This patch fixes PR2218. Very nice. Are you sure this fixes PR2218? The example there doesn't have any loads in it. > However, I'm not pretty sure that this optimization should be in > MemCpyOpt. I think that GVN is good place as well. Yes, you're right. My long term goal is to merge the relevant

Based on function names and structures, this is some version of GCC :) Any way you can post the entire .ll file? Because it's globalsmodref, it's hard to debug without the other functions, since it goes over all the functions to determine address takenness, etc :) On Tue, Jul 21, 2015 at 3:23 PM, Michael Zolotukhin <mzolotukhin at apple.com> wrote: > Hi Chandler, > > We