algorithm - Fastest Cortex M0+ Thumb 32x32=64 multiplication function? -

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does have (or can write) optimal inline assembly function arm cortex m0+ processor in thumb mode multiply 2 32-bit numbers , return 64-bit number?

as m0+ not have long multiply, way can accomplished through primitive multiplication, compiler calls __aeabi_lmul performs 64x64=64 multiplication in 34 instructions. i'm hoping faster algorithm exists, given inputs 32 bits.

so talking unsigned or signed multiplication? if signed doing 64x64=64 anyway not 32x32=64. if unsigned take source code gcc library function , modify since know upper halves of operands zero.

or @ hackers delight (hackersdelight.org) , see if there algorithm implements faster gcc library.


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