replace integer multiplication or division with shift if one of multipliers or divisor is a
power of 2

Key: HARMONY5901
URL: https://issues.apache.org/jira/browse/HARMONY5901
Project: Harmony
Issue Type: Improvement
Components: DRLVM
Reporter: Xiaoming Gu
1. Mulitiplication replacement
a. It's about integer multiplication.
b. One of two multipliers is a power of 2.
c. The power of 2 could be negative.
For example, 23*4 is transformed to 23<<2 and 23*(4) is transformed to (23<<2)*(1).
2. Division replacement
a. It's about integer division.
b. The divisor is a power of 2.
c. The power of 2 could be negative.
d. Because of roundup difference between division and shift right, the following equations
from Aleksey are used.
Baseline: q = a / (1 << d);
Optimized: q = (a + [(1 << d)  1] & (a >> 31)) >> d;
For example, 23/4 is transformed to (23+((1<<2)1)&(23>>31))>>2.
and (23)/(4) is transformed to ((23+((1<<2)1)&(23>>31))>>2)*(1).
3. Comments for SAR and SHR swapped
The comments for the two similar operations were misplaced in working_vm/vm/port/src/encoder/ia32_em64t.

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