A64: Minor code generation improvement: only load the object map if needed.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/170503004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19456 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
alexandre.rames@arm.com 2014-02-18 15:14:23 +00:00
parent dafb11f8b3
commit d54305e12a

View File

@ -888,9 +888,13 @@ Register StubCompiler::CheckPrototypes(Handle<HeapType> type,
reg = holder_reg; // From now on the object will be in holder_reg.
__ Ldr(reg, FieldMemOperand(scratch1, Map::kPrototypeOffset));
} else {
Register map_reg = scratch1;
// TODO(jbramley): Skip this load when we don't need the map.
bool need_map = (depth != 1 || check == CHECK_ALL_MAPS) ||
heap()->InNewSpace(*prototype);
Register map_reg = NoReg;
if (need_map) {
map_reg = scratch1;
__ Ldr(map_reg, FieldMemOperand(reg, HeapObject::kMapOffset));
}
if (depth != 1 || check == CHECK_ALL_MAPS) {
__ CheckMap(map_reg, current_map, miss, DONT_DO_SMI_CHECK);