Yeah, I don't remember the DEC format being poor, and some of the differences which did exist really felt like "make sure IEEE-754 is gratuitously incompatible with DEC".
Denormals/gradual underflow support in hardware was one of those, for example. DEC generally trapped on those and let a library handle it. Most of the time, gradual underflow bites people by hiding the precision loss rather than being something useful to exploit for speed.
Hardware support for it meant that people tended to "stash" information in there just like they do for NaN-boxing. AutoCAD, for example, was notorious for having a zillion denormals, none of which had anything to do with calculation.
The number of people who ever benefited from gradual underflow was ridiculously tiny while the number of people who suffered performance loss was huge. This was one of those tradeoffs that wasn't worth it for a very long time--only now that hardware is practically free does it not matter.
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Yeah, I don't remember the DEC format being poor, and some of the differences which did exist really felt like "make sure IEEE-754 is gratuitously incompatible with DEC".
Denormals/gradual underflow support in hardware was one of those, for example. DEC generally trapped on those and let a library handle it. Most of the time, gradual underflow bites people by hiding the precision loss rather than being something useful to exploit for speed.
Hardware support for it meant that people tended to "stash" information in there just like they do for NaN-boxing. AutoCAD, for example, was notorious for having a zillion denormals, none of which had anything to do with calculation.
The number of people who ever benefited from gradual underflow was ridiculously tiny while the number of people who suffered performance loss was huge. This was one of those tradeoffs that wasn't worth it for a very long time--only now that hardware is practically free does it not matter.