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litwr · 13 October 2018, 19:21

@meynaf Your code is as fast as mine! But you have just replaced i/o-routines for input and output text using high-level Amiga built-in ROM functions - it's not completely fair. I can replace PR0000 and getnum with a slower but lesser in size routines and this gives 80386 the first position again.
It is interesting that when I compile your code with cross-assembler vasm I get a bit different binary file. It has the same size but differs in 3 bytes. It shows again that 68k has too much redundancy in its ISA.
I can resume my point about why 68k lost and Intel and ARM won. 68000 and 68020 has too much redundancy in their ISA, too much complexity. When time was come to convert electronics to the new fast 6502/ARM-like standards it was much more difficult for Motorola with 68k than for Intel with x86. It was not unique. DEC completely abandoned its famous VAX series in the favor of new RISC Alpha because it was impossible to convert electronics of the huge VAX ISA. BTW this conversion is very costly and difficult therefore even today for x86 is faster to execute two instructions DEC CX and JNZ loop, than one LOOP loop. So number of x86 instructions are still not converted for the fast execution. 68k orthogonality gives less flexibility for such maneuvers. Motorola had to move towards PowerPC, because ARM was too fast. It is fascinating that ARM @8MHz could outperform 68030 @25MHz.

13 October 2018, 19:21	#506
litwr Registered User Join Date: Mar 2016 Location: Ozherele Posts: 229	@meynaf Your code is as fast as mine! But you have just replaced i/o-routines for input and output text using high-level Amiga built-in ROM functions - it's not completely fair. I can replace PR0000 and getnum with a slower but lesser in size routines and this gives 80386 the first position again. It is interesting that when I compile your code with cross-assembler vasm I get a bit different binary file. It has the same size but differs in 3 bytes. It shows again that 68k has too much redundancy in its ISA. I can resume my point about why 68k lost and Intel and ARM won. 68000 and 68020 has too much redundancy in their ISA, too much complexity. When time was come to convert electronics to the new fast 6502/ARM-like standards it was much more difficult for Motorola with 68k than for Intel with x86. It was not unique. DEC completely abandoned its famous VAX series in the favor of new RISC Alpha because it was impossible to convert electronics of the huge VAX ISA. BTW this conversion is very costly and difficult therefore even today for x86 is faster to execute two instructions DEC CX and JNZ loop, than one LOOP loop. So number of x86 instructions are still not converted for the fast execution. 68k orthogonality gives less flexibility for such maneuvers. Motorola had to move towards PowerPC, because ARM was too fast. It is fascinating that ARM @8MHz could outperform 68030 @25MHz.