Tue, 17 Sep 1991 18:11:53 GMT

Related articles |
---|

Strength Reduction napi@rangkom.MY (1991-09-17) |

Re:strength reduction ssimmons@convex.com (1991-09-17) |

Re: Strength Reduction preston@dawn.rice.edu (1991-09-17) |

Re: strength reduction albaugh@dms.UUCP (1991-09-23) |

Re: strength reduction preston@dawn.rice.edu (1991-09-25) |

Newsgroups: | comp.compilers |

From: | preston@dawn.rice.edu (Preston Briggs) |

Keywords: | optimize, bibliography |

Organization: | Rice University, Houston |

References: | 91-09-040 |

Date: | Tue, 17 Sep 1991 18:11:53 GMT |

napi@rangkom.MY (Mohd Hanafiah Abdullah) writes:

*>In Induction Variable optimization, beside reducing strength of*

*>multiplication by using addition in array references, what other strength*

*>reductions could be performed, like involving division, etc?*

Multiplication of an induction variable (IV) by a region constant (RC).

Multiplication of 2 IVs.

Squaring an IV.

Integer division (IV / RC)

Integer module (IV % RC)

Exponentiation (RC ** IV)

General polynomials in an IV may always be reduced to additions.

Many trig functions.

Further, addition may sometimes be usefully reduced.

See

Reduction of Operator Strength

Fran Allen, John Cocke, Ken Kennedy

in Program Flow Analysis

Muchnick and Jones (editors)

Prentice-Hall, 1981

Generally though, you need to handle multiplication.

The other things are fun to watch, but not very useful.

Preston Briggs

--

Post a followup to this message

Return to the
comp.compilers page.

Search the
comp.compilers archives again.