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Copyright (c) 2002, 2018, Oracle and/or its affiliates. All rights reserved.
DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
This code is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License version 2 only, as
published by the Free Software Foundation.
This code is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
version 2 for more details (a copy is included in the LICENSE file that
accompanied this code).
You should have received a copy of the GNU General Public License version
2 along with this work; if not, write to the Free Software Foundation,
Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
or visit www.oracle.com if you need additional information or have any
questions.
Strength Reduction
------------------
Strength reduction replaces an expansive operation by a cheaper one, such as
multiplication by addition or subtraction, multiplication instead of
exponentiation; use compound assignment operators such as += wherever possible,
changing code of the form a[i] = a[i] + x to a[i] += x, since they result in
fewer bytecode instructions; use shifts instead of multiplication by powers of
two, etc.
For example:
x ** 2 = x * x
2.0 * x = x + x
x / 2 = x * 0.5
Induction Variable
------------------
A variable is called an induction variables of a loop if every time the variable
changes values it is incremented or decrmented by some constant.
Basic induction variables i whose only assignments within the loop is of the
form i += c, where c is a constant.
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