inline Register MacroAssembler::encode_heap_oop_not_null(Register d, Register src) {
Register current = (src!=noreg) ? src : d; // Compressed oop is in d if no src provided.
if (Universe::narrow_oop_base() != NULL) {
sub(d, current, R30);
current = d;
}
if (Universe::narrow_oop_shift() != 0) {
srdi(d, current, LogMinObjAlignmentInBytes);
current = d;
}
return current; // Encoded oop is in this register.
}
void C1_MacroAssembler::initialize_body(Register obj, Register tmp1, Register tmp2,
int obj_size_in_bytes, int hdr_size_in_bytes) {
const int index = (obj_size_in_bytes - hdr_size_in_bytes) / HeapWordSize;
const int cl_size = VM_Version::L1_data_cache_line_size(),
cl_dwords = cl_size>>3,
cl_dw_addr_bits = exact_log2(cl_dwords);
const Register tmp = R0,
base_ptr = tmp1,
cnt_dwords = tmp2;
if (index <= 6) {
// Use explicit NULL stores.
if (index > 0) { li(tmp, 0); }
for (int i = 0; i < index; ++i) { std(tmp, hdr_size_in_bytes + i * HeapWordSize, obj); }
} else if (index < (2<<cl_dw_addr_bits)-1) {
// simple loop
Label loop;
li(cnt_dwords, index);
addi(base_ptr, obj, hdr_size_in_bytes); // Compute address of first element.
li(tmp, 0);
mtctr(cnt_dwords); // Load counter.
bind(loop);
std(tmp, 0, base_ptr); // Clear 8byte aligned block.
addi(base_ptr, base_ptr, 8);
bdnz(loop);
} else {
// like clear_memory_doubleword
Label startloop, fast, fastloop, restloop, done;
addi(base_ptr, obj, hdr_size_in_bytes); // Compute address of first element.
load_const_optimized(cnt_dwords, index);
rldicl_(tmp, base_ptr, 64-3, 64-cl_dw_addr_bits); // Extract dword offset within first cache line.
beq(CCR0, fast); // Already 128byte aligned.
subfic(tmp, tmp, cl_dwords);
mtctr(tmp); // Set ctr to hit 128byte boundary (0<ctr<cl_dwords).
subf(cnt_dwords, tmp, cnt_dwords); // rest.
li(tmp, 0);
bind(startloop); // Clear at the beginning to reach 128byte boundary.
std(tmp, 0, base_ptr); // Clear 8byte aligned block.
addi(base_ptr, base_ptr, 8);
bdnz(startloop);
bind(fast); // Clear 128byte blocks.
srdi(tmp, cnt_dwords, cl_dw_addr_bits); // Loop count for 128byte loop (>0).
andi(cnt_dwords, cnt_dwords, cl_dwords-1); // Rest in dwords.
mtctr(tmp); // Load counter.
bind(fastloop);
dcbz(base_ptr); // Clear 128byte aligned block.
addi(base_ptr, base_ptr, cl_size);
bdnz(fastloop);
cmpdi(CCR0, cnt_dwords, 0); // size 0?
beq(CCR0, done); // rest == 0
li(tmp, 0);
mtctr(cnt_dwords); // Load counter.
bind(restloop); // Clear rest.
std(tmp, 0, base_ptr); // Clear 8byte aligned block.
addi(base_ptr, base_ptr, 8);
bdnz(restloop);
bind(done);
}
}
void C1_MacroAssembler::initialize_body(Register base, Register index) {
assert_different_registers(base, index);
srdi(index, index, LogBytesPerWord);
clear_memory_doubleword(base, index);
}
