similar to: [LLVMdev] Is va_arg deprecated?

Neal, FYI, my group has added a flag to llvm-gcc for emitting the va_arg instruction (instead of lowering in the front-end), and we also have an implementation of the VAARG instruction for X86-64. (which is currently not implemented in the LLVM backend). Both of these things will be sent upstream to LLVM soon, pending some more testing and review. If you are dire need of these features now, I

target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32" target triple = "i686-pc-windows-msvc" declare void @llvm.va_start(i8**) declare void @llvm.va_end(i8**) define i64 @foo(...) { %va = alloca i8*, i32 16 ; 4 words should be enough? call void @llvm.va_start(i8** %va) %x = va_arg i8** %va, i64 call void @llvm.va_end(i8** %va) ret i64 %x }

For the variadic function error with AMD64 abi and windows calling convention on 64bits x86, I find it has been tracked in Bug 20847 (https://llvm.org/bugs/show_bug.cgi?id=20847) (http://reviews.llvm.org/D1622#inline-9345). Do we still plan to fix it? You know, I meet exactly same va_arg mistake with llvm3.7 when I enable the Uefi firmware (http://www.uefi.org/) build with clang. The ms_abi is

Hi, I am using llc (llvm 2.9) to generate the MIPS assembly, but failed when compile any codes with va_start()/va_end()/va_arg(). Here is the minimal step to reproduce the failure: llvm-gcc-4.2 -emit-llvm hello.c -c -o hello.bc llc -march=mips hello.bc -o hello.s llc show this erroe message: LLVM ERROR: Cannot select: 0xa1873a0: ch = vaend 0xa187290:1, 0xa185ae0, 0xa187318 [ID=38] 0xa185ae0:

Hi Richard, Thank you for the info. I build my code in Ubuntu-64bits with simply commands: “clang X64.c”, then run “./a.out” to see the output. If I replace my va_list, va_start, va_arg va_end with __builtin_ms_va_list, __builtin_ms_va_start, __builtin_ms_va_arg, __builtin_ms_va_end, my code will build fail in Ubuntu with below message. Do you suggest I should build it in windows and not in

Hi, So the Variable Argument Handling Intrinsics section of the LangRef (http://llvm.org/docs/LangRef.html#variable-argument-handling-intrinsics) lists an example that segfaults. Try the following on x86_64: -- 8< -- define i32 @test(i32 %X, ...) { ; Initialize variable argument processing %ap = alloca i8* %ap2 = bitcast i8** %ap to i8* call void @llvm.va_start(i8* %ap2) ; Read a

On Mon, Aug 15, 2011 at 2:18 AM, Leo Chen. <leo.q.chen at gmail.com> wrote: > Hi, > > I am using llc (llvm 2.9) to generate the MIPS assembly I would suggest trying trunk; there have been a lot of improvements recently to the MIPS backend. -Eli > but failed > when compile any codes > with va_start()/va_end()/va_arg(). > > Here is the minimal step to reproduce the

On Aug 15, 2011, at 9:42 AM, Eli Friedman wrote: > On Mon, Aug 15, 2011 at 2:18 AM, Leo Chen. <leo.q.chen at gmail.com> wrote: >> Hi, >> >> I am using llc (llvm 2.9) to generate the MIPS assembly > > I would suggest trying trunk; there have been a lot of improvements > recently to the MIPS backend. > I agree. Also, make sure you're using a MIPS

i have this code typedef long long L; typedef integer I; void test2(auto L p0, auto L p1, auto L p2, auto L p4, ...) { va_list select; va_start (select, p4); report( va_arg(select,L) ); report( va_arg(select,I) ); report( va_arg(select,L) );

I check the Mips backend for the following C code fragment compile result. It seems not correct. Is it my misunderstand or it's a bug. //ch8_3.cpp #include <stdarg.h> int sum_i(int amount, ...) { int i = 0; int val = 0; int sum = 0; va_list vl; va_start(vl, amount); for (i = 0; i < amount; i++) { val = va_arg(vl, int); sum += val; } va_end(vl);

Hi, Chris Lattner wrote: > All the non-vastart calls can be anywhere. va_end in particular codegens > to a noop on all targets llvm currently supports, fwiw. > Things go well, except for the following (pathological?) C program: int va_double_sum(int count,...){ int i,sum=0; va_list ap; va_start(ap,count); for(i=0;i<count;i++){ sum+=va_arg(ap,int); } va_end(ap);

Hi everyone, I'm interested in variadic functions and how llvm handles them. I discovered that the Clang frontend is doing a great job at lowering the va_arg (precisely __builtin_va_arg) function into target dependent code. I have also seen the va_arg function that exist at IR level. I found some information about va_arg (IR one) that currently does not support all platform. But since 2009,

Hi everyone, I have a question about ARM 32 big endian calling convention. It's about sending small structures as function argument. For example if passing 3 chars in a structure should alignment in register (argument register for passing those chars in function) be right-adjusted ? LLVM (trunk version) is passing those chars left-adjusted in register, and trying to read them like they

When I use clang on an x86-64 to spit out the LLVM, like this clang -O -S -emit-llvm varargstest.c where varargstest.c looks like this int add_em_up(int count, ...) { va_list ap; int i, sum; va_start(ap, count); sum = 0; for (i = 0; i < count; i++) sum += va_arg(ap, int); va_end(ap); return sum; } I see LLVM that looks like it's been customized for the x86-64, versus

Which part of the generated code do you think is not correct? Could you be more specific? I compiled this program with clang and ran it on a mips board. It returns the expected result (21). On Tue, Feb 19, 2013 at 4:15 AM, Jonathan <gamma_chen at yahoo.com.tw> wrote: > I check the Mips backend for the following C code fragment compile result. > It seems not correct. Is it my

I would like to be able to instrument va_arg, but when I generate a bc file for a test case using: llvm-gcc -O3 -emit-llvm vararg.c -c -o vararg.bc I do not see va_arg. Instead, it seems the args are accessed through %struct.__va_list_tag, which makes things a bit trickier to instrument. Is there a way to force llvm-gcc to use va_arg? Perhaps there is some documentation about va_list_tag or

Provide a full-fledged example of working variable arguments on X86_64, since it's easily the most popular platform. Cc: Reid Kleckner <rnk at google.com> Signed-off-by: Ramkumar Ramachandra <artagnon at gmail.com> --- docs/LangRef.rst | 44 ++++++++++++++++++++++++++++++-------------- 1 file changed, 30 insertions(+), 14 deletions(-) diff --git a/docs/LangRef.rst

I'm wonder if anyone happens to have a simplier (slower) version of bsd-snprintf.c. It seems NeXT 3.3 (unsure about 4.2) is missing mprotect(). If I could get something to replace that for a while and fix some of theses utmp in login.c issues I may have a rough port NeXT to black hardware.=) Thanks

Hi, Op 3-okt-06, om 20:48 heeft Chris Lattner het volgende geschreven: > You'd have to change it to something like: > > void foo(int X, ...) { > P = va_start(); > bar(X, P); > } > > void bar(int X, valist P) { > use(P); > } Can the other va_...-intrinsics be used in bar as were the "P = va_start" in bar? The va_start probably is unnecessary

On Tue, 3 Oct 2006, Bram Adams wrote: >> You'd have to change it to something like: >> void foo(int X, ...) { >> P = va_start(); >> bar(X, P); >> } >> >> void bar(int X, valist P) { >> use(P); >> } > > Can the other va_...-intrinsics be used in bar as were the "P = > va_start" in bar? The va_start probably is