RFR(L): 8035936: SIGBUS in StubRoutines::aesencryptBlock, solaris-sparc

[Shrinivas Joshi]

Hi,

Requesting reviews for the following change. Thanks for your time.

-Shrinivas

Bug: https://bugs.openjdk.java.net/browse/JDK-8035936
Webrev: http://cr.openjdk.java.net/~kvn/8035936/webrev/

Summary: The intrinsified AES encryption and decryption JDK API methods 
take byte arrays and offsets into these arrays as input arguments. Thus 
the stub routines can potentially read from and write to arbitrarily 
aligned addresses. SPARC load/store instructions generate 
'mem_address_not_aligned' exception when they operate on improperly 
aligned addresses. This change addresses the arbitrary alignment issue 
in case of SPARC AES crypto stub routines.

Summary of source code changes:

* src/cpu/sparc/vm/assembler_sparc.hpp:
    - Added support for ALIGNADDR(Align Address), FALIGNDATA(Align Data 
using GSR.align), EDGE8N(Edge Handling Instructions), FSRC2(F Register 
Logical Operate) and STPARTIALF(Store Partial Floating-Point) instructions

* src/cpu/sparc/vm/stubGenerator_sparc.cpp:
    - Added assertion checks to test if first element of 'int' and 
'byte' arrays are at 8-byte aligned address. HotSpot's current object 
layout guarantees this.
    - Changed single-block encrypt and decrypt stub routine names to 
match with what is used on x86.
    - Added code to address mis-aligned loads and stores. Added some 
details on the methodology used to address mis-aligned load/store 
instructions (in form of comments).
    - Since we are now explicitly testing 8-byte alignment, we are now 
using 8-byte FP load/store instructions instead of the 2*4-bytes and a 
FMOV instruction as was done previously.
    - Single-block decrypt routine now uses a lower latency FSRC2d 
instruction instead of the more expensive FMOVd instruction.
    - Multi-block (CBC) encrypt routine now does a save-restore to ease 
register pressure due to mis-alignment related code.
    - CBC encrypt routine uses G5 instead of G2 register.
    - During mis-aligned stores in CBC encrypt, we also have to save and 
reload cipher text (in F60:F62) so that it is saved in the correct byte 
order in the initialization vector which is then fed back into 
encryption of the next block. This is done by MOVdTOx and MOVxTOd 
instructions.

* src/cpu/sparc/vm/stubRoutines_sparc.hpp:
    - Increased code buffer blob size for stub routines as the current 
size of 20000 is not sufficient after addition of mis-alignment related 
code.

* src/cpu/sparc/vm/vm_version_sparc.cpp:
    - Updated comments to reflect that AES instructions are available 
starting SPARC T4, previously it was incorrectly stated as T2.
    - Updated AES intrinsics flag value sanity checks to include VIS3 
instruction capability instead of only VIS1 since VIS3 
instructions(MOVdTOx, MOVxTod) are also used by AES stubs.

* src/share/vm/classfile/vmSymbols.hpp and src/share/vm/opto/runtime.cpp
    - typo fixes

* test/compiler/7184394/TestAESBase.java
    - Added code to exercise mis-aligned loads and stores.
    - Made padding string a property that can be passed on command-line 
since certain alignment issues are not triggered with padding enabled.
    - If any of the alignment cases (encryption input, encryption 
output/decryption input and decryption output) are being tested then the 
test case now does multi-part crypto operations with an update() 
followed by doFinal(). We need to do this because certain alignment 
issues are not triggered when only doFinal() calls are used. If 
mis-alignment is not being tested then the test case excercises 
single-part operations as was the case previously.
    - In case of multi-part operations, the last chunk of input passed 
to encryption/decryption routines is set to 2*blocks long. This is again 
because mis-aligned stores during decryption are not triggered if input 
is less than 2*blocks long.

* test/compiler/7184394/TestAESDecode.java and 
test/compiler/7184394/TestAESEncode.java:
    - Exercises mulit-part mis-aligned operations when mis-alignment is 
being tested

* test/compiler/7184394/TestAESMain.java:
    - Added new @run commands to include various mis-aligned cases.
    - warm-up iterations count is now configurable.