agonc 1.1.0-beta.2

A pre-release of agonc, 1.1.0-beta.2. Reports of anything that goes wrong are very welcome, as issues.

Shifted to C99 as default mode, changed file structure to be more compatible with other software existing on the system, and roughly doubled the speed of compiled programs with a faster runtime and library.

Install: download agonc-1.1.0-beta.2.zip below and unzip it onto the root of the Agon's SD card, merging its folders with the ones already there. Then type agonc --version at the MOS prompt. The manual, as a PDF for printing, is attached too; it is also in the repository as docs/manual.

Changes

• agonc's library moves to /lib/agonc, and its intermediate files to
  /tmp/agonc, so that /lib and /tmp stay free for other programs.
  #include <agon/vdp.h> and the rest work as before, and /usrlib stays
  where it is: it is your folder, which other compilers may share.
  Upgrading from 1.1.0-beta.1: after unzipping the new release, delete
  /lib's assert.h, ctype.h, errno.h, float.h, limits.h, locale.h,
  math.h, setjmp.h, signal.h, stdarg.h, stddef.h, stdint.h,
  stdio.h, stdlib.h, string.h, time.h, crt0.s, rt.s, libc.s,
  libm.s, libagon.s and the .idx files beside them, and the folder
  /lib/agon, which agonc no longer uses.

• C99 in the default mode, all of it but variable-length arrays and
  complex numbers (__STDC_VERSION__ is now 199901L there):

  • declarations in a for and anywhere in a block, now without a warning
    (strict mode still warns);
  • _Bool, inline, restrict, __func__, flexible array members and
    hexadecimal floating constants (0x1.8p3);
  • designated initialisers ({ [2] = 1, .y = 3 }, in any order) and
    compound literals ((struct point){ 1, 2 });
  • variadic macros (__VA_ARGS__) and _Pragma;
  • snprintf, vsnprintf, vscanf, vfscanf, vsscanf, strtof,
    strtold, _Exit, isblank and va_copy;
  • printf's and scanf's hh, z and t length modifiers and %a;
    hexadecimal, inf and nan read by strtod, atof and scanf;
  • the headers <stdbool.h>, <inttypes.h> and <iso646.h>;
  • C99's <math.h>: cbrt, hypot, expm1, log1p, log2, exp2,
    the inverse hyperbolic functions, erf, erfc, lgamma, tgamma,
    the rounding functions, remainder, remquo, fma and the rest, the
    float and long double forms of every function, and the
    classification and comparison macros.

  Strict mode (-ansi) is C89 as before: there, strtod("inf", &end)
  still converts nothing. -std=c99 and -std=gnu99 select the default
  mode, as gcc's makefiles expect.

• Faster runtime and library, every assembly routine with its C kept
  beside it or checked against a C reference:

  • strlen, strcmp, strcpy, strcat, strchr, memcpy,
    memmove, memset and memchr use the eZ80's block instructions:
    string-heavy code runs about twice as fast.
  • int division and remainder work in registers and take rounds only
    for the dividend's significant bytes: x % 26 about 10 times as fast.
  • int multiplication works in registers (about 3 times as fast), and
    long multiplication uses the eZ80's 8-bit multiply.
  • long division and remainder take rounds only for the quotient's
    bytes: about 12 times as fast.
  • long long division is sized to its operands: about 35 times as fast
    for small ones.
  • qsort steps through the array without multiplying: about 3 times as
    fast.

  Together, the benchmarks in tests/bench run in about half the time.
  The multiply and divide helpers are now reentrant, and a C interrupt or
  key handler may use any arithmetic while the main program does too.

Fixes:

• A bit-field of 9 to 16 bits was read and stored as three bytes, so a
  store could undo a change to the byte after it, as in
  s.field = (s.next = 1). It is now two bytes.
• setbuf(stdin, NULL) and setvbuf(stdin, ..., _IONBF, ...) gave the
  keyboard a one-byte buffer, which the next line of input overran. Console
  input now keeps a line buffer whatever is asked.
• argv[argc] is now a null pointer even when all 32 entries are used.
• fgets(s, 1, f) returns s holding an empty string, as C requires.
• fsetpos no longer reports an unrelated earlier errno, fopen no
  longer leaves errno set after succeeding, and calloc and realloc
  set ENOMEM when a request is too large, as malloc does.
• The serial-port functions in <agon/uart.h> keep the frame pointer
  across their MOS calls.
• The passes close their input when they cannot create their output, so
  no MOS file handle is lost.
• #line rejects numbers above 8388607 instead of overflowing, and
  defined(__DATE__) and defined(__TIME__) are 1.
• A call with 32 arguments is now the error the limit of 31 promises.

agonc is written by Claude (Anthropic) with Adam Hemphill; see the README.

agonc 1.1.0-beta.1

The first public release of agonc, and a beta: it passes its own tests and three free C test suites, and it has built itself on a real Agon under MOS 2.3.3, but few people have used it yet. Reports of anything that goes wrong are very welcome, as issues.

agonc compiles ANSI C89, with its whole standard library and some of C99, on the Agon Light and Console8, under MOS 2.3.3 (and MOS 3, tested on the emulator), and builds itself there.

Install: download agonc-1.1.0-beta.1.zip below and unzip it onto the root of the Agon's SD card, merging its folders with the ones already there. Then type agonc --version at the MOS prompt. The manual, as a PDF for printing, is attached too; it is also in the repository as docs/manual.

What it has:

• C89 with a conforming strict mode (-ansi), and a default mode with C99's long long, // comments, declarations after statements and a few other extensions.
• The C89 library, <stdint.h>, and C99's long long functions; IEEE 754 float and double, correctly rounded, in software, with the most-used operations in assembly.
• <agon/mos.h>, <agon/uart.h> and <agon/vdp.h>: every MOS 2.3.3 call, the FatFS calls, the system variables, keyboard and interrupt handlers in C, the second serial port, and every documented VDU command.
• An optimiser, on by default (-O0 turns it off).
• Library indexes, so that a link reads only what a program uses.
• The manual, examples, and the specifications.

Known issue: the graphics contexts (vdp_context_save and the rest) send the documented commands, but a text background colour set after a save did not show as documented, on the emulator or on a real Agon.

agonc was written by Claude (Anthropic) with Adam Hemphill; see the README.