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Actually, if you tell the compiler to use SSE and above, it will use them extensively and even for floating point instead of x87

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Yes, it will do fun things like turn 1.0f + 1.0f into (1.0f,0,0,0) + (1.0f,0,0,0), that is better than having to deal with the old floating point stack, but doesn't really exploit the full potential of SSE instructions.

SSE has scalar instructions - like "addss", "subss" etc.

These will be used by default (at O2 without vectorization enabled) for single-precision floating point math on x86-64 (where stack-based FPU is deprecated).

Vector instructions you're referring to end with "ps", they're very unlikely to be emitted for typical fp operations.

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