[Bug target/115362] fixed_size_simd dot product recognition and sign of determinant not working for stdx::reduce

[jondaniel879 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115362

--- Comment #21 from Jon Daniel <jondaniel879 at gmail dot com> ---
The generated assembler output of

g++:
        vmaskmovps      40(%rsp), %xmm1, %xmm0
        vmaskmovps      56(%rsp), %xmm1, %xmm2
        vmulps  %xmm2, %xmm0, %xmm0

Notice the lower memory address register is taken as the second source operand

clang++:
        vmaskmovps      48(%rsp), %xmm0, %xmm2
        vmaskmovps      32(%rsp), %xmm0, %xmm3
        vmulps  %xmm3, %xmm2, %xmm2

Notice the lower memory address register is taken as the first source operand