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The compilers available at the time that the 8087 was commonplace were overall horrible and easily beaten anyway.

On the other hand, skilled humans can do very very well with the x87; this 256-byte demo makes use of it excellently: https://www.pouet.net/prod.php?which=53816

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Oh boy...more memories. About a decade later at work I identified a bottleneck in our line-drawing code. The final step was to cast two floats (a point) to integers, which the compiler turned into ftoa() calls. Unfortunately, ftoa changed and restored the floating point control flags in order to set the rounding behavior (the Intel default did not match the standard library spec). Even more unfortunately, this stalled the Pentium's instruction pipeline. Replacing the casts with a simple fld/fist pair was another 100x speedup. A few years later I noticed the compilers started adding optimization flags controlling this behavior.

Yah, I never did a very good job with x87 code generation. I'm a bit embarrassed by that.

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