similar to: [LLVMdev] RFC: Better alternative to llvm.frameallocate for use in Windows EH

On Wed, Mar 4, 2015 at 12:36 AM, John McCall <rjmccall at apple.com> wrote: > > On Mar 3, 2015, at 2:25 PM, Reid Kleckner <rnk at google.com> wrote: > > > > I realized that WinEH preparation can probably be a lot less invasive > than it is currently. > > > > Initially, when I was thinking about recovering the address of an object > in a parent stack

On Mon, May 18, 2015 at 8:40 PM, Joseph Tremoulet <jotrem at microsoft.com> wrote: > > I want to have separate normal and exceptional codepaths > > I assume you at least mean that's what you'll be doing in Clang's initial > IR generation. Do you also mean to impose this as a restriction on other > IR generators, and as a property that IR transformations must

I think adding transitions to cleanupblocks on the normal execution path would be an optimization barrier. Most passes would see the cleanupblock instruction and run the other way. It's definitely appealing from the perspective of getting the smallest possible code, but I'm OK with having no more than two copies of everything in the finally block. I think with the addition of the

This example is pretty compelling, but I still think I want to limit the scope of this change to not include this feature. It's probably reasonable to hold onto the idea as future work, though. In the meantime, frontends can decide for themselves whether they want code size or stronger optimization of cleanups by doing early outlining or not. The only way we can hit the quadratic growth from

There are some other considerations too (apologies if these were mentioned above and I missed them). Also below are initial thoughts, so apologies for any mistakes or oversights. For example, if [a, b] <- my2valuefun() works the same as local({ tmp <- my2valuefun() stopifnot(is.list(tmp) && length(tmp) == 2) a <<- tmp[[1]] b <<- tmp[[2]] }) Do we expect [a[1], b[3]]

On Mon, May 18, 2015 at 12:03 PM, Joseph Tremoulet <jotrem at microsoft.com> wrote: > Hi, > > > > Thanks for sending this out. We're looking forward to seeing this come > about, since we need funclet separation for LLILC as well (and I have > cycles to spend on it, if that would be helpful). > > > > Some questions about the new proposal: > > >

Hi, I have a question about the IR model for SEH filters (as I want to use the same model for CLR filters). In particular, when an outer filter is invoked before entering an inner finally, which piece of IR reflects the filter's side-effects? To take a concrete example, consider this C code: void foo() { int x; __try { x = 0; __try { x = 2; may_throw(); }

As stated in the design paragraph, this design does not intend to model precise CFG at instruction level since it’s complicated and unnecessary. As long as we comply C and C++ rules listed below, we achieve -EHa semantic. There is NO need to precisely model HW exception control flow at instruction-level. Your example about memcpy() is just a bug in current implementation. I will fix it so that

thank john, i have used dump() , and each blocks had pred except entery block, i get the following output: fun main entry entry: %retval = alloca i32 %0 = alloca i32 %i = alloca i32 %j = alloca i32 %a = alloca [2 x i32] %n = alloca i32 %t = alloca i32 %"alloca point" = bitcast i32 0 to i32 %1 = getelementptr inbounds [2 x i32]* %a, i32 0, i32 0 %2 = load i32*

Thanks Duncan and Ivan for the careful thoughts. I'm not sure I can follow all aspects you raised, but to give my limited take on a few: > your proposal violates a very basic property of the language, i.e. that all statements are expressions and have a value. > What's the value of 1 + (A, C = init_matrices()). I'm not sure I see the point here. I evaluated 1 + (d =

On 11 Feb 2010, at 06:53, Vikrant Shimpi wrote: > Dear Luka , > I am using qcc package in R to plot SPC charts. BUt while plotting > R chart I had a error. My question is it necessary while plotting > R Chart the group sample size must be < 25 ?. Because when I took > group sample size as 1000 it gave me error, till I took group sample > size as 26, But as sooon as

Hi, All I want to implement DSWP Which is used for parallelization of loops. For this purpose, the loop was replaced with a new basic block in main function. And new functions were created and basic blocks of Loop assigned to them.I have checked blocks and branches for Succ and Pred relation and I have not found any problems. However I get the following error: * **opt:

I am working on adding support for C++ exception handling when compiling for a native Windows target (that is a target with "MSVC" specified as the environment). Because of differences between how the native Windows runtime handles exceptions and the Itanium-based model used by current LLVM exception handling code, I believe this will require some extensions to the LLVM IR, though

I'm using the llvm-c API and want to use the JIT. I've created the following module ; ModuleID = '_tmp' @a = global i64 5 define i64 @__tempfunc() { entry: %a_val = load i64* @a ret i64 %a_val } This output is generated by LLVMDumpModule just before I call LLVMRunFunction. Which yields a LLVMGenericValueRef. However converting the result to a 64bit integer via

+nlewycky On Mon, Nov 17, 2014 at 9:36 AM, Volodymyr Kuznetsov <vova.kuznetsov at epfl.ch > wrote: > Hi Kostya, > > On Sat, Nov 15, 2014 at 1:53 PM, Volodymyr Kuznetsov < > vova.kuznetsov at epfl.ch> wrote: > > Do you think moving the pass to lib/Transform/Instrumentation but > > scheduling it during code generation would make sense ? If so, we'll >

Hi all, I have recently encountered a problem when creating LLVM IRs. I am wondering if there is a standard or easy way to create a load from a certain register? For example, CreateLoad(rbp, NAME). Thanks, Chen -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20131213/ec277276/attachment.html>

Hi Chen, > I have recently encountered a problem when creating LLVM IRs. I am wondering > if there is a standard or easy way to create a load from a certain register? > For example, CreateLoad(rbp, NAME). LLVM doesn't directly provide access to any machine registers. If you want %rbp because it's the frame pointer then for that one case there is actually an @llvm.frameaddress

Hi, Eli, Why are you under the impression that threw_exception() will not be called if optimizations are enabled? I don’t know if the -EHa Spec is clearly described in MSFT Webs. At least this proposal has described the rules for both C & C++ code. The very first rule clearly said that “no exception can move in or out of _try region., i.e., no potential faulty instruction can be moved

On Thu, 2008-04-17 at 10:49 -0700, Chris Lattner wrote: > On Thu, 17 Apr 2008, guan mailist wrote: > > Does anyone have good ideas to dynamically measure the stack size of a > > program by using LLVM. > > I am trying to add some new intrinsic functions after each "alloca" in > > bitcode. Is it a good way to do it? > > Any existing tools can help me to do

After a long tale of sorrow and woe, my colleagues and I stand here before you defeated. The Itanium EH representation is not amenable to implementing MSVC-compatible exceptions. We need a new representation that preserves information about how try-catch blocks are nested. WinEH background ------------------------------- Skip this if you already know a lot about Windows exceptions. On Windows,