Add missing runtime tests for SSE alias intrinsics

[ArunTamil21]

Add missing runtime tests for SSE alias intrinsics

While working through issue #798, I noticed several alias intrinsics had no
runtime tests even though their underlying functions were already tested.

This PR adds tests for:

• "test_mm_cvt_ss2si" (alias for "mm_cvtss_si32")
• "test_mm_cvtt_ss2si" (alias for "mm_cvttss_si32")
• "test_mm_cvt_si2ss" (alias for "mm_cvtsi32_ss")
• "test_mm_set_ps1" (alias for "mm_set1_ps")

Each test follows the same pattern as the existing tests for the underlying
functions, since these aliases just call them directly.

Part of #798.

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The reviewer was selected based on:

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[sayantn]

Could you remove these lines too please

stdarch/crates/stdarch-verify/tests/x86-intel.rs

Lines 250 to 253 in 0e22a37

	"_mm_cvt_ss2si",
	"_mm_cvtt_ss2si",
	"_mm_cvt_si2ss",
	"_mm_set_ps1",

View changes since this review

[sayantn]

Also, personally, I think it is a bit weird (and error-prone) to fully repeat the tests for aliases, considering there are quite a few of them. I would prefer a macro-based approach, but take this as a completely personal opinion.

[ArunTamil21]

@sayantn Done, removed the lines from x86-intel.rs.

Regarding the macro-based approach, I agree it's cleaner.
Would you like me to refactor the tests in this PR, or should
I do that as a separate follow-up PR?

[sayantn]

I would prefer it to be a single PR, as this PR just copying the tests anyway. If you prefer you can keep them as different commits

[ArunTamil21]

@sayantn Thanks for the feedback. I'll refactor the tests using a macro-based approach.
Could you point me to an example of how you'd prefer the macro to look ?
I tried to check the sse.rs / sse2.rs couldn't find any macros based pattern.

[sayantn]

I don't think we use a macro like that exactly, but you can make a simple macro like

macro_rules! foo_gen {
    ($($test_name:ident : $alias:ident),*) => {$(
        #[simd_test(blah)]
        fn $test_name() {
            //<< the body, but with $alias as the function name >>
        }
    )*}
}

foo_gen(foo, foo_alias);

or you can create a "meta function" like

unsafe fn test_foo_gen(actual_fn: unsafe fn()) {
    // << the body, but using `actual_fn` in place of that >>
}

#[simd_test(blah)]
fn test_foo() {
    test_foo_gen(foo);
}

#[simd_test(blah)]
fn test_foo_alias() {
    test_foo_gen(foo_alias);
}

any of these work, or if you can think of a better approach that's even better

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[ArunTamil21]

@sayantn
I've refactored all the alias tests using the meta function pattern as suggested. Each pair of alias intrinsics now shares a single impl function to avoid code duplication.
I also added the missing tests for _mm_load_ps1, _mm_store_ps1, _mm_undefined_ps, and _mm_prefetch as part of issue #798.
For the last two, since they don't produce verifiable output per Intel's docs (prefetch only affects cache behavior, and _mm_undefined_ps returns indeterminate elements), the tests just verify that the functions compile and execute without crashing. Added a comment in each test explaining why.
Let me know if anything needs adjustment!

[sayantn]

Thanks, looks nice. But I don't think we need tests for prefetch and undefined, we already have instruction tests to ensure that they produce the correct assembly

[ArunTamil21]

Thanks @sayantn for the clarification — removed both. Good to know assert_instr already covers correctness for intrinsics with no verifiable output.