SDCC

SDCC is the toolchain used in MSXGL to compile, assemble and link the sources files.

Supported version:

• Embedded: SDCC 4.2.0
• Last tested: SDCC 4.4.0 RC3 (Windows) and SDCC 4.4.0 (Linux)

Assembler

The assembler, sdasz80, is based on ASxxxx cross assembles.

sdasz80 syntax is almost standard except for:

• Define instructions numeral values: must be prefixed with # character.
• Define directive: must be prefix with . character.
• Access to IX and IY register using offset: offset have to be write before the register name into parentheses.

Standard	sdasz80
; Numeral ld a, 100 and 01111100b ld hl, 1234h ; Directive db 100 dw 1234h ; IX/IY offset ld e, iy[0] ld d, iy[1]	; Numeral ld a, #100 and #0b01111100 ld hl, #0x1234 ; Directive .db 100 .dw 0x1234 ; IX/IY offset ld e, 0(iy) ld d, 1(iy)

Versions

SDCC 4.2.0

Currently recommended version for MSXgl.

• ⭐ Main features:
  • New calling convention (use register to pass function parameters)

• 🧾 Full change-log:
  • C23 memset_explicit
  • Support for --oldralloc has been removed from the z80 backends.
  • Full support for __z88dk_callee for the z80 backends.
  • Support for a new __sdcccall(1) calling convention in the z80 AS NEW DEFAULT.
  • Removed support for --profile for z80 backends.
  • The z80n port Z80N Core minimum version has been raised from 1.0 to 2.0.
  • Improved rematerialization support in the z80 backends.

• ⚠️ Known issues:
  • None

SDCC 4.3.0

• ⭐ Main features:
  • Support for undocumented Z80 instructions

• 🧾 Full change-log:
  • Added all new general mnemonics from ASxxxx 5.40 except for .bank and enabled for all ports
  • sm83: sdasgb now can output cycles in listing and sz80 has accurate cycles for this processor except for branching
  • struct / union parameters and return.
  • div standard library function family.
  • Many fixes for the type system and _Generic.
  • Adopted more of GCC, QuickC and tinycc tests.
  • C2X bit-precise integer types and bit-fields thereof for. C2X nullptr, char8_t, memalignment, unreachable, typeof, typeof_unqual, auto. C2X keywords bool, true, false, alignas, alignof, static_assert. C2X bit and byte utilities.
  • C90-C17 function declarators without prototypes.
  • C99 variably modified types.
  • call_once.
  • _sdcc_external_startup renamed to __sdcc_external_startup and supported for all ports.
  • makeshift support for long double as another alias for float.

• ⚠️ Known issues:
  • Most of the projects can increase significantly in final size.
  • Bug with undocumented Z80 instructions generation that can generate compilation errors.

SDCC 4.4.0

• ⭐ Main features:
  • Native support for ASCII R800, the MSX turbo R's CPU.

• 🧾 Full change-log:
  • Optimizations for rotations.
  • Generalized constant propagation.
  • New command line option --syntax-only to only parse the input.
  • Added C99 header inttypes.h
  • Added library functions imaxabs, imaxdiv, llabs, strtoimax, strtoll, strtoull, strtoumax, wcsncmp, wcstoimax, wcstol, wcstoll, wcstoul, wcstoull, wcstoumax
  • New r800 port to better support the ASCII Corp R800 and Zilog Z280.
  • Improved optimizations for code speed for stm8, pdk, z80 (and related).

• ⚠️ Known issues:
  • On Windows, win32 version just doesn't works and win64 is... absent. You can use win64 version of SDCC 4.4.0 RC3 (same content than the official release).
  • Some projects can increase significantly in final size.
  • Some projects are broken when compiled with SDCC 4.4.0 (Clock sample and Phenix Corrupta project).

Links

For more information:

• SDCC homepage
• SDCC documentation
• ASxxxx documentation