Fastest way to clamp a real (fixed/floating point) value?

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Both GCC and clang generate beautiful assembly for the following simple, straightforward, portable code:

double clamp(double d, double min, double max) {
  const double t = d < min ? min : d;
  return t > max ? max : t;
}

> gcc -O3 -march=native -Wall -Wextra -Wc++-compat -S -fverbose-asm clamp_ternary_operator.c

GCC-generated assembly:

maxsd   %xmm0, %xmm1    # d, min
movapd  %xmm2, %xmm0    # max, max
minsd   %xmm1, %xmm0    # min, max
ret

> clang -O3 -march=native -Wall -Wextra -Wc++-compat -S -fverbose-asm clamp_ternary_operator.c

Clang-generated assembly:

maxsd   %xmm0, %xmm1
minsd   %xmm1, %xmm2
movaps  %xmm2, %xmm0
ret

Three instructions (not counting the ret), no branches. Excellent.

This was tested with GCC 4.7 and clang 3.2 on Ubuntu 13.04 with a Core i3 M 350.
On a side note, the straightforward C++ code calling std::min and std::max generated the same assembly.

This is for doubles. And for int, both GCC and clang generate assembly with five instructions (not counting the ret) and no branches. Also excellent.

I don’t currently use fixed-point, so I will not give an opinion on fixed-point.

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