ARM64: Share address computation across SIMD LDRs/STRs.
For array accesses the element address has the following structure:
Address = CONST_OFFSET + base_addr + index << ELEM_SHIFT
Taking into account ARM64 LDR/STR addressing modes address part
(CONST_OFFSET + index << ELEM_SHIFT) can be shared across array
access with the same data type and index.
For example, for the following loop 5 accesses can share address
computation:
void foo(int[] a, int[] b, int[] c) {
for (i...) {
a[i] = a[i] + 5;
b[i] = b[i] + c[i];
}
}
Test: test-art-host, test-art-target
Change-Id: I46af3b4e4a55004336672cdba3296b7622d815ca
diff --git a/compiler/optimizing/code_generator_vector_arm64.cc b/compiler/optimizing/code_generator_vector_arm64.cc
index 57f7e6b..478bd24 100644
--- a/compiler/optimizing/code_generator_vector_arm64.cc
+++ b/compiler/optimizing/code_generator_vector_arm64.cc
@@ -783,6 +783,12 @@
/*out*/ Register* scratch) {
LocationSummary* locations = instruction->GetLocations();
Register base = InputRegisterAt(instruction, 0);
+
+ if (instruction->InputAt(1)->IsIntermediateAddressIndex()) {
+ DCHECK(!is_string_char_at);
+ return MemOperand(base.X(), InputRegisterAt(instruction, 1).X());
+ }
+
Location index = locations->InAt(1);
uint32_t offset = is_string_char_at
? mirror::String::ValueOffset().Uint32Value()