[9] RFR(S): 8143208: compiler/c1/6855215/Test6855215.java supports_sse2() failed

[Zoltán Majó]

Hi,


please review the patch for 8143208.

https://bugs.openjdk.java.net/browse/JDK-8143208

Problem: The failure is triggered on linux_x86_32 with -XX:UseSSE=0 
because the MacroAssembler::has_negatives() method attempts to emit a 
movdl instruction that is available only if UseSSE >= 2.

Solution:
- Change the has_negatives() method to check if SSE42 intrinsics are 
enabled before attempting to emit SSE instructions. The check is 
performed on the  value of 'UseSSE42Intrinsics' flag for consistency 
reasons: All method emitting string-related intrinsics check the value 
of that flag before emitting SSE instructions.
- Change the processing of command line-flags to not allow setting 
'UseSSE42Intrinsics' to true if SSE4.2 has been disabled or is not 
available.
- Add asserts that fail if UseSSE<4 to all places where 
UseSSE42Intrinsic assumed to be true.

Webrev:
http://cr.openjdk.java.net/~zmajo/8143208/webrev.00/

Testing:
- JPRT;
- executed failing test locally with linux_x86_32 build.

Thank you and best regards,


Zoltan