tree ade27385c4aa0db96956b873321a7994e69acd8d
parent 1e739fa94947147953c53e92964e0e9e1eac0526
author Vladimir Marko <vmarko@google.com> 1521484969 +0000
committer Vladimir Marko <vmarko@google.com> 1528814782 +0100

Simplify const-string.indexOf().

Simplify String.indexOf() called on empty or single-char
constant string. We see these patterns in inlined
    java.net.URI$Parser.scan(int, int, String, String)
called with constant strings from other URI$Parser methods.
The empty string simplification allows constant folding
and DCE to remove some of the code. The single-character
string simplification avoids entrypoint call overhead.

Test: New tests in 458-checker-instruct-simplification
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I4d3c997a8d6220202d481bbf8cbf280832c27cd7