Before this change both ExecutionContext and CallFrame were created
before executing function/module/script with a couple exceptions:
- executable created for default function argument evaluation has to
run in function's execution context.
- `execute_ast_node()` where executable compiled for ASTNode has to be
executed in running execution context.
This change moves all members previously owned by CallFrame into
ExecutionContext, and makes two exceptions where an executable that does
not have a corresponding execution context saves and restores registers
before running.
Now, all execution state lives in a single entity, which makes it a bit
easier to reason about and opens opportunities for optimizations, such
as moving registers and local variables into a single array.
Instead of allocating these in a mixture of ways, we now always put
them on the malloc heap, and keep an intrusive linked list of them
that we can iterate for GC marking purposes.
This required setting things up so that all function objects can plop
a PrimitiveString there instead of an AK string.
This is a step towards making ExecutionContext easier to allocate.
This works by adding source start/end offset to every bytecode
instruction. In the future we can make this more efficient by keeping
a map of bytecode ranges to source ranges in the Executable instead,
but let's just get traces working first.
Co-Authored-By: Andrew Kaster <akaster@serenityos.org>
This loosens the connection to the AST interpreter and will allow us to
generate SourceRanges for the Bytecode interpreter in the future as well
Moves UnrealizedSourceRanges from TracebackFrame to the JS namespace for
this
Now ExecutionContext has vector of values that will represent values
of local variables.
This vector is initialized in ECMAScriptFunctionObject::internal_call()
or ECMAScriptFunctionObject::internal_const() using number of local
variables provided to ECMAScriptFunctionObject by the parser.
