jak-project/docs/markdown/progress-notes/changelog.md

Language Changes

V0.1

• The GOAL language version has been set to 0.1
• Calling a function with unknown argument/return types is now an error instead of a warning
• Getting a method of an object or type with method returns the correct type for methods using the _type_ feature
• The object-new macro will now type check arguments
• The size argument to (method object new) is now an int instead of int32
• Using set! incorrectly, like (set! 1 2) will now create an error instead of having no effect
• GOOS now has a fmt form which wraps libfmt for doing string formatting.
• GOOS now has an error form for throwing an error with a string to describe it
• GOAL if now throws errors on extra arguments instead of silently ignoring them
• The first 1 MB of GOAL memory now cannot be read/written/executed so dereferencing a GOAL null pointer will now segfault
• The runtime now accepts command line boot arguments
• The runtime now defaults to loading KERNEL.CGO and using its kernel-dispatcher function.
• The runtime now accepts a -nokernel parameter for running without KERNEL.CGO.
• The runtime will now refuse to load object files from another major GOAL version
• Using &+ and &+! now produces a pointer with the same type as the original.
• There is a &- which returns a uint and works with basically any input types
• The & operator works on fields and elements in arrays
• The &-> operator has been added
• The new operator can create arrays and inline arrays on heaps
• The value of deftype is now none
• Creating a method with more than 8 arguments is an error instead of a crash.
• The defconstant form for defining a constant in GOAL but not GOOS has been added
• Both defconstant and defglobalconstant throw an error if you define a constant with the same name as a symbol.
• The uint64 type now uses 8 bytes instead of 81 in a type (this was a typo)
• deftype allows basics/structures with a field that is the same type as the basic/structure.
• Doing a define-extern with a type of type will forward declare the type.
• deftype now has a :no-runtime-type flag to disable the creation of a runtime type.
• There is a declare-type form for forward declaring types to allow circular dependencies.
• Types that are structure but not basic can request that they be tightly packed when possible with :pack-me.
• Using method on a forward declared type is an error. The old behavior was to get a method of type, which is confusing.
• Loading an int64/uint64 gives a int/uint, like the other register integers.
• Defining a type with deftype will auto-generate an inspect method.
• The new operator can now create static structures and basics and set fields to integers or symbols.
• The neq? operator now works when used outside of a branch condition (previously it generated a syntax error)
• Methods which do not return a value no longer cause the compiler to abort
• The &+ form now accepts more than two arguments.
• The &+ form now works on inline-array and structure.
• In the case where the type system would use a result type of lca(none, x), the result type is now none instead of compiler abort.
• The "none value" is now (none) instead of none
• Creating a field of 128-bit value type no longer causes a compiler crash
• 128-bit fields are inspected as <cannot-print>
• Static fields can now contain floating point values
• Fixed a bug where loading a float from an object and immediately using it math would cause a compiler crash
• Arrays of value types can be created on the stack with new.

V0.2

• Breaking change: return type of a function using return-from #f to return a value from the entire function is now the lowest common ancestor of all possible return values.
• Fixed bug where return-from could reach outside of an inlined function.
• Fixed bug where return-from might not behave correctly when returning from inside a let inside an inlined function.
• Added fmin and fmax floating point min and max. These work on multiple arguments and use the minss/maxss instructions for the best performance.
• Added imul64 instruction for doing a real 64-bit multiplication. This must be used when porting code that looks at the hi register after an EE mult.
• Added shl, shr, and sar shifts which take a constant integer. These cannot be used with a variable shift amount.
• Added bitfield types to the type system
• Added the ability to cast integers to bitfield types
• Fixed a bug where casting between integer types with the that did not involve emitting code would permanently change the type of the variable.
• Added a :disassemble option to asm-file to disassemble functions for debugging purposes.

V0.3

• Added typechecking when setting fields of a type.
• Added inline assembly .ret, .sub, .push, and .pop.
• Added rlet to declare register variables.
• Added :color #f option to inline assembly forms to exclude them from the coloring system.
• Added asm-func to declare for purely assembly functions.
• Enum values now work where constant integers are expected.
• The boolean values #f and #t now are gotten as symbol objects, not values of symbols.
• In a static field initialization, you can use #f and #t instead of '#f and '#t
• Added no-typecheck option to define.
• Reworked type checking for set!. You may now use #f for non-numeric types.
• Fixed a bug where arguments to a method were unmodifiable.
• Fixed a bug where multiple anonymous lambda functions in the same file would throw a compiler error related to function name uniqueness.
• Method declarations can now use compound types. Previously they could only use simple types due to a mistake in deftype parser.
• Added a declare option for allow-saved-regs to let asm-funcs use saved registers in special cases
• Improved register allocation for the above case to avoid inserting extra moves to and from temp registers.
• Fixed a bug where early returns out of methods would not change the return type of the method.
• Fixed a bug where the return instruction was still emitted and the overridden return type of asm-func was ignored for methods
• Rearranged function stack frames so spilled register variable slots come after stack structures.
• Added stack allocated and constructed basic/structure types.
• Fixed a bug where functions with exactly 8 parameters created a compiler error.

V0.4

• Breaking change: added new link kind to link table format. Code compiled with previous versions will still work, but code compiled in V0.4 that uses static pairs will cause a "unknown link table code 5" error.
• Added support for static pairs and lists. Symbols, integers, and strings are supported.
• Added much better support for setting fields of statics. Now you can set constants, symbols, strings, pairs, integers, floats, or other statics, including inlined structures/basics! Also uses the full type system for typechecking
• Fixed a bug where accessing an inline basic field did not apply the 4-byte basic offset.
• Made string/float constants go in the main segment when they are declared in the top-level segment, instead of the top-level segment. This is what GOAL seems to do (not 100% sure yet) and avoids issues where you set something to a string constant in the top-level. This avoids the possibility of memory bugs at the cost of more memory usage (likely very little additional memory).
• Added support for boxed arrays. They can be created with new and indexed with ->. The compound type (array <elt-type>) is used to describe an array with a given content type.
• Added reset-here option for rlet.

V0.5

• Breaking change: the register class xmm for a single float was renamed to fpr to distinguish it from other uses of xmm registers.
• Breaking change: the message format for reset and shutdown messages sent between the listener and runtime has changed.
• Improved code-generation quality where accessing a field or similar with an offset of zero from a base register.
• The listener now uses message IDs to more robustly handle the situation where a response messages comes, but is extremely late, or if some sent messages are skipped.
• Fixed bug where references to the debug segment using RIP-relative links were not set to zero by the linker when the debug segment isn't loaded.
• The rlet form now supports 128-bit vector float registers with the vf register class.
• Added support for "vector float" assembly operations, including lvf, svf, xor, sub, add, and blend.
• Added the ability to spill floating point variables to the stack if there aren't enough registers.
• Improved back up and restore of xmm registers
• Fixed an off-by-one in move eliminator (previous version was correct, but did not generate as good code). Complicated functions are 2 to 10% smaller.
• Improved getting a stack address.
• Improved getting the value of #f, #t, and ().
• Accessing a constant field of an array now constant propagates the memory offset like field access and avoids a runtime multiply.
• Fixed a bug where loading or storing a vf register from a memory location + constant offset would cause the compiler to throw an error.
• Accessing array elements uses more efficient indexing for power-of-two element sizes.
• Added a local-vars form for declaring a bunch of local variables for the decompiler.
• Split method into method-of-type and method-of-object to avoid ambiguity
• Fixed bug where (-> obj type) caused a compiler error when obj had compile time type of array (the fancy boxed array)
• Fixed use-after-free if the top-level form fails to compile and you continue trying to compile stuff.
• and and or are more efficient and the type of the result is more specific: LCA(symbol, cases...)
• print-type now fully compiles the argument and returns the result instead of none

V0.6

• There is no longer a separate compiler form for variable vs. constant shifts. Instead the compiler will pick the constant shift automatically when possible. The shifts are called sar, shl and shr, like the x86 instructions.
• Static type reference link data now has the correct number of methods. This prevents errors like dkernel: trying to redefine a type 'game-info' with 29 methods when it had 12, try restarting when you did not actually redefine the number of methods.
• Added get-info to figure out what something is and where it's defined.
• Added autocomplete to get auto-completions for a prefix.
• Added add-macro-to-autocomplete to add a macro to the auto-completer.

V0.7

• There is now an option for allow-misaligned which allows the alignment of an struct type to be less than 16-bytes when inlined, without enabling array packing. This seems like a stupid option, but GOAL has this in some places, so we support it too.
• In method declarations in a deftype, you can no longer provide argument names. There was ambiguity when parsing a compound typespec vs named argument. The names were not used for anything.
• 128-bit integer register variables (i128) are now supported. These work with assembly forms, set!s between registers, and set!s of memory locations with type (pointer uint128) or (pointer int128).
• Fixed a bug where the compiler would abort if had to spill an xmm register containing an i128 value.
• Added .pextlw, .pextuw, .pcpyld, and .pcpyud assembly forms
• Fixed a bug where uint128 or children defined with local-vars would end up using a 64-bit GPR instead of a 128-bit XMM.
• Fixed a bug where 128-bit variable spills could be misaligned, causing a segfault at vmovaps.
• Added .ppach and .pceqw
• Fixed a bug where setting 128-bit / 64-bit variables from each other only did a 32-bit set
• Added support for creating a static bitfield where fields may not be known at compile time.
• Added support for (size-of <typename>)
• Fixed a bug where creating a stack array of 0 sized caused a compiler assertion. It is now a normal compiler error.
• Fixed a bug where the repl history was not loaded on compiler start
• Branch target addresses in the disassembly generated by md, asm-file with :disassemble and (declare (print-asm)) are now correct
• Fixed a segfault when the goal-library.gc contains an (exit)
• defenum now creates real types. Boxed arrays of enums and bitfields correctly have runtime type of the parent integer.
• Added a :copy-entries <typename> to copy entries from a previous bitfield.
• Adding a duplicate entry to an enum now generates a compiler error.
• Added .psubw assembly form
• Changed .ftoi to VCVTTPS2DQ to make the rounding behavior match the PS2 (truncate).
• Forward declaring a type with declare-type also forward declares the global holding the runtime type object.
• The new method of basic now has a method return type of _type_. Previously it was basic, meaning you always needed to declare new with the right type.
• Using (new and (the binteger inside static pair definitions is now supported
• Invalid static pairs now have nice errors instead of exiting the compiler
• Added unsigned division (previously signed division was used for unsigned numbers)
• Use shifts (64-bit) for positive power of two multiply and divide. Otherwise use 32-bit. This matches GOAL.
• Allow setting a 64-bit or less memory location from a 128-bit variable (upper bits are discarded).
• It is now a compiler error to declare a bitfield type where a field crosses bit 64.
• Fixed a bug where a let/immediate lambda with an argument with type of child of int128/uint128 would end up in a 64 bit register.
• Support accessing and setting fields of a 128-bit bitfield type.
• Fixed a bug where the mask constant for clearing a bitfield was not computed correctly
• Support 128-bit bitfields inside of static structure
• Support 128-bit bitfield constants
• Support dynamic construction of 128-bit bitfield values

V0.8 New Calling Convention for 128-bit

• 128-bit values may now be used in function arguments and return values.
• Fixed a bug where reader errors in goal-lib.gc or any error in goos-lib.gs would cause a crash
• Fixed a bug where ''a or similar repeated reader macros would generate a reader error.
• Fixed a bug where reader macros without a following form would trigger an assert.
• It is now possible to take the address of a lexical variable. The variable will be spilled to the stack automatically.