On 02/02/2016 01:33 PM, Vladimir Ivanov wrote: > Looks good. Thanks Vladimir!
> Please, add -Xverify:all to all tests on string concat. There is little need: all string concat tests are calling String concat stubs from non-privileged callers, and hence are verified. E.g. new regression test does fail with verification error even without -Xverify:all. But it is a good idea to force verification in concat tests just in case that ever fails: http://cr.openjdk.java.net/~shade/8148787/webrev.02/ This new patch flies through full JPRT without a hitch. Cheers, -Aleksey > Best regards, > Vladimir Ivanov > > On 2/2/16 10:00 AM, Aleksey Shipilev wrote: >> Anyone? This looks like a trivial fix. >> >> -Aleksey >> >> On 02/01/2016 10:47 PM, Aleksey Shipilev wrote: >>> Hi, >>> >>> Please review the fix for a corner case in StringConcatFactory exactness >>> check, which produces invalid bytecode: >>> https://bugs.openjdk.java.net/browse/JDK-8148787 >>> >>> Note that this happens when all three things align: >>> a) BSM is called directly, as Java method -- javac would never >>> produce >>> such a String concat shape; >>> b) BC_SB_SIZED_EXACT strategy is used, so exactness check can be >>> applied; >>> c) -Djava.lang.invoke.stringConcat.debug=true is set, forcing >>> exactness check to run; >>> >>> The issue is with exactness debug check using a temporary local variable >>> when the local variable table is small (like it is in non-arg case). The >>> code can be reformulated without using temporary variables, with a >>> creative use of "swap" instruction. >>> >>> Ironically, the bug is within the debugging code, so we don't care about >>> its performance at all: >>> http://cr.openjdk.java.net/~shade/8148787/webrev.01/ >>> >>> Cheers, >>> -Aleksey >>> >> >>
