phunanon / chika Goto Github PK

Currently, on a 32-bit system, ChVM::exeForm requires 24B for parameters and 5B for locals.
Firstly, IType type before evaluating next argument can be made global, as can probably uint8_t* f. This would cut down the params to 16B and locals to 4B.

Next, itemnum firstParam and itemnum nArg can be managed through a bespoke stack, so that per function call these exist only once and not per every form.
Locals formCode, firstArgItem, and formData can be put on a bespoke stack also.

Finally, as the compiler is aware of the depth of recur's, implicit and explicit returns, it could inform the VM on how far to unroll.

Like Insitux, rather than use form-marking and a separate exeForm(), count the number of arguments to an operation and execute in one for-loop.

Syntax

(if cond1 (form)) //nil if false
(if cond1 (form1) (else))

(if
  cond1 (form1)
  cond2 (form2)
  ...
  (else))

Implementation

Extending the already existing if special form. Evaluates all true conditions' forms, or if no conditions were true the else form. May be possible to avoid inflation of SpecialFormData.

It may be possible to have most native operations accept no parameters, as ChVM::iBytes et al could be globally configured with a pre-calculated byte offset. Then native operations, instead of using p0, p0 + 1, etc, could use i(0), i(1). This would not only simplify code, but pay off in performance as most op's right now calculate a byte offset repeatedly through ChVM::i or ChVM::iBytes.

Currently very innocuous op's like len, nth, type, not have their arguments duplicated to the stack before selecting only a small amount of data from them. A new special form for certain op's could ensure parameters and variable bindings are instead served as constants where appropriate. Even sect could benefit from this, with major rewriting.

This will generally improve performance as a stack copy is avoided. #4 would see real benefit.

Syntax

(file-read "file path") => blob of file contents or nil
(file-write "file path" blob) => boolean of success
(file-append "file path" blob) => boolean of success

Implementation

The ChVM harness will expose these three functions for the same file system dependency as loading programs.

Syntax

(case value
  case1 (form)
  case2 (form)
  ...
  (else form))

Implementation

As special form, providing short-circuited evaluation. Evaluates the form of the first matching value.