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BSzili · 09 December 2021, 07:12

Did something change recently regarding the code generation for -m68060? I rebuilt Duke3D to test the recently added control presets, and it now has some graphics glitches, sometimes CON parsing won't work, and the maps won't load. I tried to compare the asm output with -m68040 and it looks like the compiler now emits FPU instructions for certain multiplications. For example what compiles to

muls.l #936,d0

becomes

Code:

	fmove.l d1,fp0
	fmul.l #936,fp0
	fmod.s #0x4f800000,fp0
	fmove.l fp0,d2

This could be a problem, because I change the FPU rounding for the custom 64-bit integer math replacement routines, which probably messes with the ones generated by the compiler. Is it possible to disable this optimization?

Edit: This is a small function that now has FPU instructions with -m68060, but with -m68040 it doesn't:
http://franke.ms/cex/z/T7rj6q

09 December 2021, 07:12	#1329
BSzili old chunk of coal Join Date: Nov 2011 Location: Hungary Posts: 1,293	Did something change recently regarding the code generation for -m68060? I rebuilt Duke3D to test the recently added control presets, and it now has some graphics glitches, sometimes CON parsing won't work, and the maps won't load. I tried to compare the asm output with -m68040 and it looks like the compiler now emits FPU instructions for certain multiplications. For example what compiles to muls.l #936,d0 becomes Code: fmove.l d1,fp0 fmul.l #936,fp0 fmod.s #0x4f800000,fp0 fmove.l fp0,d2 This could be a problem, because I change the FPU rounding for the custom 64-bit integer math replacement routines, which probably messes with the ones generated by the compiler. Is it possible to disable this optimization? Edit: This is a small function that now has FPU instructions with -m68060, but with -m68040 it doesn't: http://franke.ms/cex/z/T7rj6q Last edited by BSzili; 09 December 2021 at 07:54.