s_mul64To128.c File Reference

#include <stdint.h>
#include "platform.h"
#include "primitiveTypes.h"

Include dependency graph for s_mul64To128.c:

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Functions
struct uint128	softfloat_mul64To128 (uint64_t a, uint64_t b)

Function Documentation

softfloat_mul64To128()

struct uint128 softfloat_mul64To128	(	uint64_t	a,
		uint64_t	b )

Definition at line 43 of file s_mul64To128.c.

{
    uint32_t a32, a0, b32, b0;
    struct uint128 z;
    uint64_t mid1, mid;
 
    a32 = a>>32;
    a0 = a;
    b32 = b>>32;
    b0 = b;
    z.v0 = (uint_fast64_t) a0 * b0;
    mid1 = (uint_fast64_t) a32 * b0;
    mid = mid1 + (uint_fast64_t) a0 * b32;
    z.v64 = (uint_fast64_t) a32 * b32;
    z.v64 += (uint_fast64_t) (mid < mid1)<<32 | mid>>32;
    mid <<= 32;
    z.v0 += mid;
    z.v64 += (z.v0 < mid);
    return z;
 
}