RFR: JDK-8211061: Tests fail with assert(VM_Version::supports_sse4_1()) on ThreadRipper CPU

[Roman Kennke]

Involving hotspot-compiler-dev...

> Some tests fail with:
> 
> # Internal Error
> (/home/rkennke/src/openjdk/jdk-jdk/src/hotspot/cpu/x86/assembler_x86.cpp:3819),
> pid=5051, tid=5055
> # Error: assert(VM_Version::supports_sse4_1()) failed
> 
> When running hotspot/jtreg:tier1 on my ThreadRipper 1950X box. On my
> Intel box, this works fine. It looks like it attempts to generate
> fast_sha1 stubs, which use Assembler::pinsrd() but then runs into
> supports_sse4_1().
> 
> The failing tier1 tests are:
> compiler/c1/Test6579789.java
> compiler/c1/Test6855215.java
> compiler/cpuflags/TestSSE4Disabled.java
> 
> The failing tests seem to disable SSE4 or SSE altogether and check if it
> still compiles fine. This does not go well for the SHA1 and SHA256 stubs
> because they use SSE4.1 instructions. It seems that it compiles on my
> Intel box because that doesn't support_sha(), and thus disables those
> intrinsics altogether.
> 
> The proposed fix is to check for SSE4.1 present before enabling the
> affected intrinsics.
> 
> Bug:
> https://bugs.openjdk.java.net/browse/JDK-8211061
> Webrev:
> http://cr.openjdk.java.net/~rkennke/JDK-8211061/webrev.00/
> 
> Testing: hotspot/jtreg:tier1 failed before, now passes
> 
> Thanks,
> Roman
>