similar to: [LLVMdev] How can I remove Intrinsic Functions during llvm-gcc compilation?

Thanks a lot for your answer. As what you said, I can not have any options to avoid generating this kind of intrinsic for byte code. Is it possible to modify gcc and ask it take all memset liked functions as a general function call? I know this solution is less performance efficient, but I would like to have it for my llvm assembly level modification works. But anyway, thanks for you help. Hao

Hi Hao Shen, > I am using llvm-gcc --emit-llvm to generate byte code. With llvm > readable ll format, I found some standard C library function such as > llvm.memset. this is not a C library function, it is an LLVM intrinsic. An intrinsic is analogous to a builtin in gcc. An intrinsic may be expanded out into a code sequence by the compiler, or may get turned into a library call (which

SHEN Hao wrote: > Thanks a lot for your answer. > As what you said, I can not have any options to avoid generating this kind > of intrinsic for byte code. Is it possible to modify gcc and ask it take > all memset liked functions as a general function call? I know this solution > is less performance efficient, but I would like to have it for my llvm > assembly level modification

On Mon, May 10, 2010 at 7:19 PM, John Criswell <criswell at uiuc.edu> wrote: > SHEN Hao wrote: >> Thanks a lot for your answer. >> As what you said, I can not have any options to avoid generating this kind >> of intrinsic for byte code. Is it possible to modify gcc and ask it take >> all memset liked functions as a general function call? I know this solution

On 27.10.2012, at 18:24, Benjamin Kramer <benny.kra at gmail.com> wrote: > > On 27.10.2012, at 18:15, Sean Silva <silvas at purdue.edu> wrote: > >> How does this affect freestanding implementations? > > This transform is disabled with -fno-builtin or -ffreestanding. Thinking a bit more about this, it looks like the way -ffreestanding is implemented in clang is

On Tue, May 29, 2012 at 8:46 PM, Anton Korobeynikov <anton at korobeynikov.info > wrote: > > How do I disable that feature? I've tried -fno-builtin and/or > -ffreestanding > > with no success. > clang (as well as gcc) requires that freestanding environment provides > memcpy, memmove, memset and memcmp. > > PS: Consider emailing cfedev, not llvmdev. > Hi,

Even with -ffreestanding LLVM generates memcpy/memset? Does this mean some passes do not honor this flag? If you really wanted to prevent libcalls, you could technically translate those memcpy/memset to loops in lowering. Kevin On Sat, Oct 15, 2016 at 4:10 PM, Wolfgang McSneed via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Hi Mehdi and Joerg, > > Thanks for your fast

Hi, I have the following program: // test.c #include <stdlib.h> struct foo_t { int x[1024]; }; __thread struct foo_t g_foo; void bar(struct foo_t* foo) { g_foo = *foo; } int main() { struct foo_t* f = (struct foo_t*)malloc(sizeof(struct foo_t)); bar(f); return 0; } When I compile it with clang I see that it inserts memcpy() in function bar(): $ clang -v clang version 3.2 (trunk

On Tue, May 29, 2012 at 9:40 PM, Chandler Carruth <chandlerc at google.com>wrote: > > How do I disable that feature? I've tried -fno-builtin and/or >>>>> -ffreestanding >>>>> > with no success. >>>>> clang (as well as gcc) requires that freestanding environment provides >>>>> memcpy, memmove, memset and memcmp.

On Tue, May 29, 2012 at 9:16 PM, Chandler Carruth <chandlerc at google.com>wrote: > > How do I disable that feature? I've tried -fno-builtin and/or >>> -ffreestanding >>> > with no success. >>> clang (as well as gcc) requires that freestanding environment provides >>> memcpy, memmove, memset and memcmp. >>> >>> PS: Consider

deadal nix via llvm-dev wrote on Mon, 17 Aug 2015: > OK, what about that plan : > > Slice the aggregate into a serie of valid loads/stores for non atomic ones. > Use big scalar for atomic/volatile ones. > Try to generate memcpy or memmove when possible ? Are memcpy/memmove guaranteed to be handled inline, i.e., without a call to libc? Or are there plans to do this in the context

On Tue, May 29, 2012 at 10:50 AM, Chandler Carruth <chandlerc at google.com> wrote: > On Tue, May 29, 2012 at 10:46 AM, Dmitry Vyukov <dvyukov at google.com> wrote: >> >> On Tue, May 29, 2012 at 9:40 PM, Chandler Carruth <chandlerc at google.com> >> wrote: >>>>>>> >>>>>>> > How do I disable that feature? I've

On Tue, May 29, 2012 at 10:46 AM, Dmitry Vyukov <dvyukov at google.com> wrote: > On Tue, May 29, 2012 at 9:40 PM, Chandler Carruth <chandlerc at google.com>wrote: > >> > How do I disable that feature? I've tried -fno-builtin and/or >>>>>> -ffreestanding >>>>>> > with no success. >>>>>> clang (as well as gcc)

I'm sorry that I should remove the comment. In fact my question is about the "float (i32)* (float (i32)*)*", why we use this kind of return type instead of just "float (i32)*". Thanks a lot. Hao On Mon, Apr 12, 2010 at 5:42 PM, Duncan Sands <baldrick at free.fr> wrote: > Hi Hao Shen, > >> %4 = call float (i32)* (float (i32)*)* @get_ptr(float (i32)* @a1)

Hi all, LLVM is smart that it can synthesize llvm.memset, llvm.memcpy etc. from loops, which can be lowered into calls to memset, memcpy and so on. Is there an option that can disable this optimization? For some cases, I do not want the code to depend on libc. Thanks in advance! Bin -------------- next part -------------- An HTML attachment was scrubbed... URL:

> How do I disable that feature? I've tried -fno-builtin and/or -ffreestanding > with no success. clang (as well as gcc) requires that freestanding environment provides memcpy, memmove, memset and memcmp. PS: Consider emailing cfedev, not llvmdev. -- With best regards, Anton Korobeynikov Faculty of Mathematics and Mechanics, Saint Petersburg State University

On Tue, May 29, 2012 at 9:52 AM, Dmitry Vyukov <dvyukov at google.com> wrote: > On Tue, May 29, 2012 at 8:46 PM, Anton Korobeynikov < > anton at korobeynikov.info> wrote: > >> > How do I disable that feature? I've tried -fno-builtin and/or >> -ffreestanding >> > with no success. >> clang (as well as gcc) requires that freestanding environment

On Tue, May 29, 2012 at 11:11 AM, Jeffrey Yasskin <jyasskin at googlers.com>wrote: > On Tue, May 29, 2012 at 10:50 AM, Chandler Carruth <chandlerc at google.com> > wrote: > > On Tue, May 29, 2012 at 10:46 AM, Dmitry Vyukov <dvyukov at google.com> > wrote: > >> > >> On Tue, May 29, 2012 at 9:40 PM, Chandler Carruth <chandlerc at google.com >

"float (i32)* (float (i32)*)*" is not a return type. According to the description of the 'call' instruction in LLVM Assembly Language Reference Manual (http://llvm.org/docs/LangRef.html#i_call) this is a signature of the pointer to function value being invoked (which includes the return type). In your case the full signature is printed because get_ptr returns a pointer to

Dear all, I compiled c program with llvm and found something strange with function pointer as following small example . ------------- In C Code -------------- float a (int value) { return value + 1; }; typedef float (*funcptr_t) (int); funcptr_t get_ptr(funcptr_t p) { return p; } float result = get_ptr(a)(4); ------------- In LLVM Code -------------- %4 = call float (i32)* (float