Anton Stenmark wrote:
I'm working on porting LuaJIT to the PlayStation®Vita. It uses an
ARM CPU but I've had to make some changes to compile LuaJIT with the
Sony toolchain. I've gotten it up and running but the math library
functions all just return trash. For example, math.sqrt(X) always
returns 3.0.
Most likely the wrong ABI was selected. This can easily happen if
you don't use the standard build process.
Check the developer docs for the C calling conventions: are
floating-point numbers passed in integer registers or in FPU
registers?
Note there are three standard FPU/ABI variants for ARM: no-FPU/soft,
FPU/softfp and FPU/hardfp. Check the compiler defines for __SOFTFP_
(probably undefined) and __ARM_PCS_VFP (1 for hardfp, undefined for
softfp calling conventions). src/Makefile checks for the resulting
LJ_ARCH_HASFPU and LJ_ABI_SOFTFP defines and sets the appropriate
DynASM defines -D FPU and/or -D HFABI. You'll get weird errors if
those are wrong.
--Mike
