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Function `dmd.backend.divcoeff.udiv_coefficients`

Find coefficients for Algorithm 4.2: Optimized code generation of unsigned q=n/d for constant nonzero d


						
				extern(C) bool udiv_coefficients
				(
				

				  int N,
				

				  ulong d,
				

				  int* pshpre,
				

				  ulong* pm,
				

				  int* pshpost
				

				) nothrow @safe;

Input

N 32 or 64 (width of divide) d divisor (not a power of 2)

Output

*pshpre pre-shift *pm factor *pshpost post-shift

Returns

true Use algorithm: t1 = MULUH(m, n) q = SRL(t1 + SRL(n - t1, 1), shpost - 1)

false Use algorithm: q = SRL(MULUH(m, SRL(n, shpre)), shpost)

Authors

Walter Bright

License

Boost License 1.0