» [MMX 优化: How to optimize for the Pentium family of microprocessors] - 26.4 Bit test (all processors)
26.4 Bit test (all processors) BT, BTC, BTR , and BTS instructions should preferably be replaced by instructions like TEST, AND, OR, XOR , or shifts on PPlain and PMMX. On PPro, PII and PIII, bit tes... 发表于 2000-04-02
标签: MMX 优化 | Bit
» [MMX 优化: How to optimize for the Pentium family of microprocessors] - 26.15 Bit scan (PPlain and PMMX)
26.15 Bit scan (PPlain and PMMX) BSF and BSR are the poorest optimized instructions on the PPlain and PMMX, taking approximately 11 + 2*n clock cycles, where n is the number of zeros skipped. The fol... 发表于 2000-04-02
标签: MMX 优化 | Bit