This patch reduces memory consumption for strings such as "0" or "123"
by 8 bytes and "4294967295" by 16 bytes. The hash computation is changed
for using the lower 16 bits for these strings which is much faster than
converting the value to string first and compute the hash. The trade-of
is a small overhead when strings are created or concatenated.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Properties are changed to a type and value pair instead of a pointer to an internal
representation. Functions such as ecma_op_object_get_[own_]property do not
return with property pointers anymore.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The ecma_op_object_get_[own_]property calls should be phased out from
the project eventually and virtual properties should be introduced instead.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Removing a lot of ECMA_PROPERTY_VALUE_PTR macro calls. The only drawback
is free callbacks for native objects cannot be deleted anymore. Redefining
a free callback is a rare case, so this trade-of is acceptable.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Zero out all globals (and remove unnecessary init() functions).
Move snapshot globals to a temporary stack variable.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Currently the static variables of the allocator are moved into a
global structure.
The future plan is supporting multiple context models with different
advantages and disadvantages. Users can select the most appropriate
context model for their own use case. This context model must be
selected at compile time using compiler defines.
Currently only one model is implemented, which will be the default
context model: the context is stored in global variables, so only
a single context is available which always exists.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Since upper/lower case conversions are unspecified by the standard,
we convert ASCII characters only, and a few other characters for
testing purposes. Because these are just random cases, it is better
to remove them before the release. At some point we could add a
unicode compatible case conversion which can be enabled at compile
time.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The "length" property name is the most frequently used built-in string
and also frequently created by various hot-paths. New functions are
added to improve the speed of the "length" string creation.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Allocate a single memory block for strings, rather than a separate string header
and string characters block. In the past strings were split into 8 byte chunks,
and large amount of legacy code is designed for that representation. However the
current allocator allows block allocation so we don't need those complicated
algorithms anymore. This patch is a cleanup rather than an optimization.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Short summary of the changes:
- The ecma_reference_t is removed, and its helper functions are deleted.
- The delete operation does not depend on ecma_reference_t anymore.
- A new resolve function is added which returns the current value
of a named binding in the context chain.
- The vm_op_set_value does not perform type conversions when its arguments
has the appropriate types.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The new literal storage keeps ecma strings rather than having a
custom string implementation which duplicates the string management
routines. Conversions between string implementations are eliminated
which improved the performance by 4%.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Several internal properties are removed and directly stored as
part of the object. Faster built-in and JS function processing.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Skip put result phase for opcodes which put their
result onto the stack or they don't have result at all.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The number of delete opcodes is reduced to two from six. The
range of numbers which can be included in the byte code is
doubled from (-127,127) to (-256,256).
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
or no arguments at all. To improve the performance, the branch argument
flag is changed into a get argument type which eliminates a flag check
for all executed opcodes. Furthermore branch opcodes skip the put result
phase by changing the "break" to "continue" statements.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The implementation is simplified and optimized
resulting the removal a large amount of code.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The cache stores only real properties now, because storing NULLs has
little benefit according to tests. Since only real properties are
stored now, there is no need to create real references to objects
and property names, which reduces the keeping of dead objects after
garbage collection.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The ecma_op_to_boolean return value is changed to bool for faster
evaluation, and no need to swap operandos of relational compare.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
the three boolean arguments of ecma_create_named_data_property and the
two boolean arguments of ecma_create_named_accessor_property are combined
into one uint8_t argument. On ARM-32 it is preferred to have less than
four arguments, since these arguments can be passed in registers.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
function is removed and incorporated into ecma_op_general_object_put. Also most
properties are directly created / updated instead of using ecma_builtin_helper_def_prop.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
- Branch argument information is encoded in the vm byte
code data, so CBC flags are not loaded anymore
- The free_flags variable is removed from the vm_loop
- Two cases are removed from "get arguments", argument
processing is simplified
- The two opcode tables are merged to one
- The VM_OC_POP opcode has no result, so the break is changed to continue.
- The VM_OC_PUSH_NUMBER can use ecma_make_integer_value.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
counter is one, dereferencing the value frees its allocated memory.
In this case we return early.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
String, Boolean) to use ecma-values. When the value of a Number object is
a small integer number, this change reduces the memory consumption, since no
double is allocated.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
and comments. Space consumed by opcode triplets are reduced to 16 bits
down from 32 bits. This reduces the opcode triplet tables by 220 bytes.
New symbolic constants and defines were also added to describe common
operations.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
names were replaced by empty strings before that. The snapshot form
of tests/jerry/arguments.js fails because of this issue.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
itself seems a step back, but the primary aim is opening future
optimization opportunities. The list of changes follows:
- Property is changed to be an abstract type, which has type, flags,
and a value. It does not have a name anymore and property pointers
cannot be compressed.
- Full (32 bit) ecma values can be property values. This allows
using non-compressed pointers for ecma values in the future.
- The property chain is not restricted to the same item anymore,
it can contain hash maps, arrays in the future.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
The positive side effect is that the maximum Jerry memory is increased to 512K.
Furthermore a slight (1.3%) performance improvement was measured on RPi2 with
SunSpider.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
memory consumption, because the new allocator uses less memory if
the size as available when a block is freed. Snapshot generation
is also simplified.
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Remove ecma_completion_value_t, and add an extra bit to
ecma_value_t to represent errors. From the long list of
completion types only normal and error remained.
JerryScript-DCO-1.0-Signed-off-by: László Langó [email protected]
JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg [email protected]
Zoltan Herczeg