On 12/21/2010 8:54 AM, dos386 wrote: > AFAIK the inline ASM is more painful in WATCOM than in Boreland C or > CC386 compilers (I ever tested the latter one only). The are also > pre-brewn int86() int386() and maybe more functions to fire the INT > instruction but don't ask me how they exactly work. > >
I have done a bit of inline ASM in both Borland Turbo C++ and Open Watcom, and OW isn't that hard to use and is clearly superior for optimized code. Borland (at least Turbo) lets you touch the registers directly using them like variables (_AX, _BX, etc.). That part is nice. But I'm quite certain that as soon as you drop into inline ASM that Borland kills all of the optimizations it was doing with the registers. So if you are writing high performance code and want to use ASM, you cause performance side-effects that are not desirable. The #pragma aux lets you declare which registers you want to use as parameters, which registers are used for output, and which registers are used in the function. This lets the compiler work the inline ASM into the rest of the code flow and preserve optimization if possible. The professional Borland products might have a similar feature, but Turbo did not ... Mike ------------------------------------------------------------------------------ Forrester recently released a report on the Return on Investment (ROI) of Google Apps. They found a 300% ROI, 38%-56% cost savings, and break-even within 7 months. Over 3 million businesses have gone Google with Google Apps: an online email calendar, and document program that's accessible from your browser. Read the Forrester report: http://p.sf.net/sfu/googleapps-sfnew _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
