[SYCL] Add --ffast-math tests

[pgorlani]

This patch adds tests for intel/llvm#5801

[s-kanaev]

I can't get purpose of sycl::all for bool converted for integer here.
What's purpose of the test?

[pgorlani]

The purpose of the test is to check if all vector components are equal implying that the ::native function and the regular one return the same values.

Let me know if it is fine, otherwise I can change it.

[s-kanaev]

Per SYCL 2020 spec, all(igeninter) Returns 1 if the most significant bit in all components of x is set; otherwise returns 0.
On line 29 a boolean is provided instead.

[pgorlani]

Thanks for pointing this out, I misunderstood the initial message.

I think that the operator== returns a signed integer vector of size 4, in which each component is equal to -1 (all bits are set) if the corresponding elements of r[0] and r[1] have the same value, 0 otherwise (no bit is set). For reference, see Table 141.

[s-kanaev]

Right. operator== on host return vector of rel_t which is defined here https://github.com/intel/llvm/blob/cb5e8ae54d2e55e9edc0bad35b57fcad39e4f090/sycl/include/CL/sycl/types.hpp#L124

[s-kanaev]

For char, short, int and long it's cahr short int and long respectively. For any other type it's a mere boolean.

[pgorlani]

It depends on the size of the type. So, in the case of floats the returned vector type is made of cl_int as mandated by the SYCL specifications linked in my previous message.

[s-kanaev]

/verify with intel/llvm#5801

[pgorlani]

Shall you merge this PR?

[pgorlani]

Hi @steffenlarsen, shall you merge this PR?

[pgorlani]

Many thanks, @steffenlarsen!