Optimization

Does Vtune(hardware event-based sample) supprot KVM based open-stack environment)?

Hi all,

According to the manual :

EBS(hardware event-based ) analysis within a virtual machine is supported only in VMware Fusion* 5 virtual environment.

Now we are using open-stack environment based on KVM. Does Vtune support hardware event-based sample in our lab?

Thanks

Max

Pure virtual call behaviour difference between VS and ICC

Hi,

The following code works if compiled with VS but fails with ICC:

class A {
public:
	  virtual void F() = 0;
};

class B : public A {
public:
	  virtual void F() = 0;
};

class C : public B  {
public:
	  virtual void B::F() override {}
};

int _tmain(int argc, _TCHAR* argv[])
{
	  C c;
	  A* a = &c; 
	  a->F();
	  return 0;
}

Obviously, removing the 2nd F declaration in B or the "B::" part from F’s definition in C will remove the issue.

possible icc bug with for loop condition?

Hi,

I have a program which does 1-byte vector sum using SSE intrinsics.

When I compile it with Intel compiler (ICC 15.0.1, x86_64, Linux, SandyBridge CPU) it segfaults, it looks like the end condition of the loop is not checked correctly. Same code works with GCC.

My only optimization flag -s "-O3" (When compiling with -O1 the program works).

icc compile error on OS X

The code:
--------------------------
#include

int main() {
#ifdef __clang_version__
printf("%s\n", __clang_version__);
#endif
}
---------------------------

__clang_version__ is a builtin macro defined by clang, and is supposed to be irrelevant to icc. But icc emits a compile error when compiling this code:

test.c(5): error: extra text after expected end of number
printf("%s\n", __clang_version__);
^

This looks like a bug.

Specs:
OS X 10.10.3
icc 15.0.2

Vtune(hardware event-based sample) supprot KVM based open-stack environment)

According to the manual :

EBS(hardware event-based ) analysis within a virtual machine is supported only in VMware Fusion* 5 virtual environment.

Now we are using open-stack based on KVM. Does Vtune support hardware event-based sample in our lab?

Thanks

Max

prefetch keyword misnomer?

Dear forum,

Looking at the assembly code, the prefetch intrinsics function with _MM_HINT_T2 hint is compiled to vprefetch2, which, according to MIC instruction set manual, is a non-temporal L2 prefetch. This seems to contradict the temporal nature implied in "T". Or did I miss anything?

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