similar to: [LLVMdev] A question about GetElementPtr common subexpression elimination/loop invariant code motion

I'm attempting to modify a parser generator to emit LLVM code instead of C. So far the experience has been trivial, but I am now running into an error regarding labels that I can't seem to solve. Situation 1: A label is used immediately after a void function call (l6 in this case): <snip> %tmp26 = load i32* @yybegin, align 4 %tmp27 = load i32* @yyend, align 4 call void

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

Hi, I'm using LLVM 2.7 right now, and I found "opt -std-compile-opts" has missed some opportunities for optimization: define void @spa.main() readonly { entry: %tmp = load i32* @dst-ip ; <i32> [#uses=3] %tmp1 = and i32 %tmp, -16777216 ; <i32> [#uses=1] %tmp2 = icmp eq i32 %tmp1, 167772160 ; <i1> [#uses=2]

On Mon, 29 Jan 2007, Gil Dogon wrote: > Now the problem with this code , is that the calculation of the address > mat[i][j] which is done by the (two) getelementptr instructions > is quite expensive (involving at least two multiplications and one > addition) hence it actualy should have been moved out of the inner loop. Right. > and not twice. Anyway this is just a syptom of a

Hi, I have this piece of code: tm = local ? localtime(&curr) : gmtime(&curr); if (!tm) return NULL; which translates into something like: ---------------------------------------------- entry: %iftmp.0 = alloca %struct.tm*, align 8 %tm = alloca %struct.tm*, align 8 ... // Declares iftmp.0 as iftmp.0 call void @llvm.dbg.declare( { }* %iftmp.0, { }* bitcast

Hi Mikael, You are obtaining warning, not an error, right? The most arm cores, including arm1136, can execute mul with rd = rm. So, you can ignore this warning. Lauro 2007/6/12, Peltier, Mikael <m-peltier at ti.com>: > > > > > Hello, > > > > I want to compile a LLVM file into an executable running on ARM platform. > > I use LLVM 2.0 with the following

Hello, I've come across another example: I'm compiling with clang -S -emit-llvm -std=gnu99 -O3 clang version 2.9 (trunk 118238) Target: x86_64-unknown-linux-gnu Thread model: posix I take the code: int loops(int x) { int ret = 0; for(int i = 0; i < x; i++) { for(int j = 0; j < x; j++) { ret += 1; } } return ret; } and the

Hi, While playing around on the LLVM, I tried this code: int sum(int n) { if (n == 0) return 0; else return n + sum(n-1); } and this is what "llvm-gcc -O2" gave me: define i32 @sum(i32 %n) nounwind { entry: %tmp215 = icmp eq i32 %n, 0 ; <i1> [#uses=1] br i1 %tmp215, label %bb10, label %tailrecurse.bb10_crit_edge tailrecurse.bb10_crit_edge: ; preds =

Hello, I want to compile a LLVM file into an executable running on ARM platform. I use LLVM 2.0 with the following command lines: llvm-as -f -o test.bc test.ll llc -march=arm -mcpu=arm1136j-s -mattr=+v6 -f -o test.s test.bc arm-linux-gnu-as -mcpu=arm1136j-s test.s With the last command, I obtain the following error: rd and rm should be different in mul The bad instruction is

I'm attempting to instrument virtual function calls in my code. After each virtual call I'm calling my own registerMethod function, with an integer marking the location of the call and a pointer to the function that was called. However, and this is where I get confused, the function pointer doesn't match any of the functions in my module. I'd hoped to call

David Peixotto <dmp <at> rice.edu> writes: > I am seeing the wf loop get optimized just fine with llvm 2.8 (and almost as good with head). I rechecked this and am I actually seeing the same results as you. I think I must have made a stupid mistake in my tests before - sorry for the noise. However, I found that we have a phase ordering problem which is preventing us getting as much

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

Hi all, while writing a testcase thate needed to do a grep containg {, I found that the DejaGNU test framework didn't handle those very well. It's a bit of a fuss to escape accolades properly, but most of all the framework seemed to silently ignore errors in the escaping (and just not run the command then). See [1]. Fixing the framework resulted in 80 of the tests failing. I spent the

Hi all, I have been writing a pass to heapify some alloca's (it is pessimistization, not optimization). For example, in the following control flow graph, there is a call to malloc inserted in block BB12. In order to avoid memory leak, free's are needed. The free cannot be inserted in BB23 because BB23 is not dominated by BB12. There are two ways to go I can think of here. One way is to

PRE normally uses a latest placement algorithm to do something of the sort. I don't know about GVN/PRE, but older version of PRE might have it. Just placing the calls to free at the predecessors (dominated by BB12) of the dominance frontier of BB12 seems to work, however. Is there anything wrong with this? H. On Tue, Nov 12, 2013 at 11:30 PM, Bin Tzeng <bintzeng at gmail.com> wrote:

On May 22, 2014, at 3:51 PM, Chandler Carruth <chandlerc at google.com> wrote: > > On Thu, May 22, 2014 at 4:42 PM, Louis Gerbarg <lgg at apple.com> wrote: > The problem that the above transform is technically illegal because “When indexing into a (optionally packed) structure, only i32 integer constants are allowed (when using a vector of indices they must all be the same

Thanks. Can you file bugzilla reports? I'll look at the first one soon. Evan On Feb 5, 2009, at 8:08 AM, Roman Levenstein wrote: > Hi, > > While testing my new register allocators on some test-cases, I've > noticed that LLVM misses sometimes some optimization opportunities: > > 1) LocalSpiller::RewriteMBB seems not to propagate the information > about e.g. Spills

----- Original Message ----- > From: "Chandler Carruth" <chandlerc at google.com> > To: "Louis Gerbarg" <lgg at apple.com> > Cc: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Thursday, May 22, 2014 7:09:49 PM > Subject: Re: [LLVMdev] RFC: Indexing of structs vs arrays in getelementpointer > > > > >

https://bugzilla.mindrot.org/show_bug.cgi?id=2207 Bug ID: 2207 Summary: Potential NULL deference, found using coverity Product: Portable OpenSSH Version: -current Hardware: Other OS: FreeBSD Status: NEW Severity: enhancement Priority: P5 Component: sshd Assignee:

Hi, While testing my new register allocators on some test-cases, I've noticed that LLVM misses sometimes some optimization opportunities: 1) LocalSpiller::RewriteMBB seems not to propagate the information about e.g. Spills between MBBs.In many cases, where MBB B1 has only one predecessor MBB B2, B1 could reuse the information about the physical registers that are in the live-out set of B2.