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>

1 files changed, 10 insertions, 0 deletions

diff --git a/vm/compiler/codegen/arm/Thumb2/Factory.cpp b/vm/compiler/codegen/arm/Thumb2/Factory.cpp
index b9265e823..e062369c7 100644
--- a/vm/compiler/codegen/arm/Thumb2/Factory.cpp
+++ b/vm/compiler/codegen/arm/Thumb2/Factory.cpp
@@ -1153,11 +1153,21 @@ static void storePair(CompilationUnit *cUnit, int base, int lowReg, int highReg)
     storeBaseDispWide(cUnit, base, 0, lowReg, highReg);
 }
 
+static void storePair(CompilationUnit *cUnit, int base, int displacement, int lowReg, int highReg)
+{
+    storeBaseDispWide(cUnit, base, displacement, lowReg, highReg);
+}
+
 static void loadPair(CompilationUnit *cUnit, int base, int lowReg, int highReg)
 {
     loadBaseDispWide(cUnit, NULL, base, 0, lowReg, highReg, INVALID_SREG);
 }
 
+static void loadPair(CompilationUnit *cUnit, int base, int displacement, int lowReg, int highReg)
+{
+    loadBaseDispWide(cUnit, NULL, base, displacement, lowReg, highReg, INVALID_SREG);
+}
+
 /*
  * Generate a register comparison to an immediate and branch.  Caller
  * is responsible for setting branch target field.