JIT: Combine shift & sub for monitor unlock.

Optimize monitor unlock for ARM Thumb2 JIT.
Monitor unlock performs a logical shift left
and sub, replace it with a sub capable of
performing the shift in the same instruction.

This improves performance for usecases involving code
executing in Dalvik.

Change-Id: Iaf062d750c3bc941926f3c3b8a64dc9c7984a477
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>
JIT: Hoist loop load operations above loop.

Hoists Dalvik frame load operations outside of loops, when possible.
This improves performance in most loops, and is noticable in many
applications.

Change-Id: Ibe42b509b50a13f19758fd923f31d703e33a51c6
Signed-off-by: Henrik Smiding <henrik.smiding@stericsson.com>
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>
JIT: Allow use of cbz/cbnz for conditional branch gen.

Optimize conditional branch generation when comparing
with zero for ARM JIT. When possible use cbz/cbnz
instead of cmp+beq/cmp+bne.

This improves performance for usecases involving
code execution in Dalvik.

Change-Id: I8f7c44c87eb73d4da00a48fd86220a62cb0515f5
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>
JIT: Use rsb and shift in easy multiply.

For easy multiplication using reverse subtract (when
lit is 2^n-1) use the barrel shifter for rsb.

This improves arithmetic performance for code executing
in Dalvik. E.g String.hashCode.

Change-Id: Ifb086dcec344b30fd3e392ac21d508b43e820cdc
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>
JIT: Combine add with shift.

Optimize logical shift for ARM JIT.
Whenever logical shift is followed by an add,
try to replace it with an add capable of performing
the shift in the same instruction.

This improves performance for usecases
involving code executing in Dalvik.

Change-Id: I3cb807b6d6ef4b053a19e2703676a93a930eb963
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>
JIT: Combine add with shift and offset for array load & store.

Optimize long and double array load / store for ARM JIT.
Array load / store performs a logical shift left and add,
replace it with add capable of performing shift in the
same instruction.
Array load / store performs an add instead of using offset
for vldr/vstr. Replace the add and vldr/vstr with a vldr/vstr
that is capable of handling offset.

This improves performance for usecases involving long and double
array code execution in Dalvik. E.g WindowOrientation.

Change-Id: I90220c349ab936cdba1987139ccdf4dc31d7bbb0
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>

Conflicts:
	vm/compiler/codegen/arm/Thumb/Gen.cpp
	vm/compiler/codegen/arm/Thumb2/Gen.cpp