Added Increment and Decrement bytecode ops to support this. Postfix
updates use a temporary register to preserve the original value.
Note that this patch only implements Identifier updates. Member
expression updates are a TODO.
This is a very basic implementation of glGetfloatv. It will only give a
result when used with GL_MODELVIEW_MATRIX. In the future
we can update and extend it's functionality.
This limits the size of each block (currently set to 1K), and gets us
closer to a canonical, more easily analysable bytecode format.
As a result of this, "Labels" are now simply entries to basic blocks.
Since there is no more 'conditional' jump (as all jumps are always
taken), JumpIf{True,False} are unified to JumpConditional, and
JumpIfNullish is renamed to JumpNullish.
Also fixes#7914 as a result of reimplementing the loop logic.
Previously useradd would not check if a username already existed on the
system, and would instead add the user anyway and just increment the
uid. useradd should instead return an error when the user attempts to
create already existing users.
This change removes the mmap inside of Block in favor of a growing
vector of bytes. This is favorable for two reasons:
- We don't take more space than we need
- There is no limit to the growth of the vector (previously, if
the Block overstepped its 64kb boundary, it would just crash)
However, if that vector happens to resize, any pointer pointing into
that vector would become invalid. To avoid this, this commit adds an
InstructionHandle<Op> class which just stores a block and an offset
into that block.
This was missing from Value::is_array(), which is equivalent to the
spec's IsArray() abstract operation - it treats a Proxy value with an
Array target object as being an Array.
It can throw, so needs both the global object and an exception check
now.
This ensures that "while", do...while, "for" expressions have a
properly initialized result value even if the user terminated
the loop body via break or the loop body wasn't executed at all.
Previously SwitchStatement::execute() would return <empty> when hitting
break, continue or empty consequent block. This was not in line with
the standard.
This partially reverts c6ce7c9326.
The munmap part of that change was good, but we can't seal the blocks
since that breaks NewString and other ops that have String members.
This commit introduces the concept of an accumulator register to
LibJS's bytecode interpreter. The accumulator register is always
register 0, and most simple instructions use it for reading and
writing.
Not only does this slim down the AST, but it also simplifies a lot of
the code. For example, the generate_bytecode methods no longer need
to return an Optional<Register>, as any opcode which has a "return"
value will always put it into the accumulator.
This also renames the old Op::Load to Op::LoadImmediate, and uses
Op::Load to load from a register into the accumulator. There is
also an Op::Store to put the value in the accumulator into another
register.
This commit makes it possible to instantiate `Vector<T&>` and use it
to store references to `T` in a vector.
All non-pointer observers are made to return the reference, and the
pointer observers simply yield the underlying pointer.
Note that the 'find_*' methods act on the values and not the pointers
that are stored in the vector.
This commit also makes errors in various vector methods much more
readable by directly using requires-clauses on them.
And finally, it should be noted that Vector cannot hold temporaries :^)
The methods of this class were all over the place, this commit reorders
them to place them in a more logical order:
- Constructors/Destructor
- Observers
- Comparisons and const existence checks
- Mutators: insert
- Mutators: append
- Mutators: prepend
- Mutators: assignment
- Mutators: remove
- OOM-safe mutators: insert
- OOM-safe mutators: append
- OOM-safe mutators: prepend
- OOM-safe size management
- Size management
- Iterators
This fixes a bug where a Utf8View was created with data from a temporary
string, which was immediately deleted. This lead to a use-after-free
issue. This also changes most occurences for StringBuilder::to_string in
URLParser to use ::string_view(), as the value is passed as StringView
const& most of the time anyways.
This fixes oss-fuzz issue 34973.
When a code point is invalid, the full string was outputted to the debug
output. For large strings, this can make the system quite slow.
Furthermore, one of the cases incorrectly assumed the data to be null
terminated. This patch modifies the debug statements not to print the
full string.
This fixes oss-fuzz issue 35050.
