On Wednesday, April 12, 2006 @ 9:34 PM, John Perry wrote:
Carlos E. R. wrote:
Remember that the intel x86 processors did not come with floating point math: that was done by an add on procesor, and it was expensive. I'm not sure when they started to have the f. math unit was included in the main procesor, but somewhere in the pentium series, I guess.
The first microprocessor to have on-chip floating-point hardware was the 80486DX. All before that, from all vendors, used coprocessors, if they had any floating-point hardware at all.
Therefore, in the PC world compilers had to include libraries for simple things as multipliying 2.3 * 5.4. Even gcc (or the kernel?) still contains
an (optional) emulation library.
Even mainframes didn't have floating-point hardware; until Intel shocked the world with the 8087, everyone said there was no possibility in the foreseeable future of doing floating-point in hardware :-). Once Intel showed the way, of course, everyone went into a crash program to catch up.
John Perry
When you say "mainframes didn't have floating-point hardware ...", how far back in the mainframe world are we speaking? For example, did the IBM 360 have floating point hardware, or did that not come along until the 370 or 30xx machines? Greg Wallace