Use the new syntax in the mips, pdp, powerpc tables to declare
functions before calling them. These declarations prevent compiler
warnings about implicitly declaring functions. They also provide
prototypes of the function parameters.
Also fix a warning in the powerpc table: use `bsearch(...) != NULL` to
avoid converting the pointer from bsearch() to an int.
The syntax for topgen is a block `{...}` among the parameters in the
top table. It looks like the syntax of LLgen, but topgen doesn't
allow nested blocks, so declarations like `struct whatever {...};`
don't work. The token OPEN_BRACKET that begins a declaration_block
doesn't conflict with the LETTER that begins a parameter_line or the
'%' that begins a separator.
Because a block writes a #line command to gen.h, a parameter line now
also writes a #line command to gen.h, so it doesn't get a wrong line
number from a previous block.
Use switch.h to reduce warnings from clang about implicit declarations
of functions. I used `grep ... do_*.c | sed ... | sort`, and some
manual editing, to make the big list of Do???() functions.
Edit C code to reduce warnings from clang. Most warnings are for
implicit declarations of functions, but some warnings want me to add
parentheses or curly braces, or to cast arguments for printf().
Make a few other changes, like declaring float_cst() in h/con_float to
be static, and using C99 bool in ego/ra/makeitems.c and
ego/share/makecldef.c. Such changes don't silence warnings; I make
such changes while I silence warnings in the same file. In
float_cst(), rename parameter `str` to `float_str`, so it doesn't
share a name with the global variable `str`.
Remove `const` from `newmodule(const char *)` in mach/proto/as to
silence a warning. I wrongly added the `const` in d347207.
For warnings about implicit declarations of functions, the fix is to
declare the function before calling it. For example, my OpenBSD
system needs <sys/wait.h> to declare wait().
In util/int, add "whatever.h" to declare more functions. Remove old
declarations from "mem.h", to prefer the newer declarations of the
same functions in "data.h" and "stack.h".
Use C89 size_t for sizes from sizeof() or to malloc() or realloc().
Remove obsolete (unsigned) casts. Sizes were unsigned int in
traditional C but are size_t in C89.
Silence some clang warnings. Add the second pair of round brackets in
`while ((ff = ff->ff_next))` to silence -Wparentheses. Change
`if (nc_first(...))/*nothing*/;` to `(void)nc_first(...);` to silence
-Wempty-body. The code in compute.c nc_first() had the form
`if (x) if (y) s; else t;`. The old indentation (before 10717cc)
suggests that the "else" belongs to the 2nd "if", so add braces like
`if (x) { if (y) s; else t; }` to silence -Wdangling-else.
Shuffle extern function declarations. Add missing declaration for
LLparse(). Stop declaring RENAME(); it doesn't exist. Move some
declarations from main.c to extern.h, so the C compiler may check that
the declarations are compatible with the function definitions.
Assume that standard C89 remove() is available and doesn't need the
UNLINK() wrapper.
In lib/incl, don't need to include <stdio.h> nor <stdlib.h> to use
assert().
Remove alloc.h. If you don't clean your build, then an outdated
BUILDDIR/obj/util/LLgen/headers/alloc.h will survive but should not
cause harm, because nothing includes it. Don't need to remove alloc.h
from util/LLgen/distr.sh, because it isn't there.
Run the bootstrap to rebuild LLgen.c, Lpars.c, tokens.c.
The ACK builds an internal LLgen without installing it. The new
target would rebuild LLgen's own parser using the ACK's internal
LLgen. Keep bootstrap.sh, which uses an installed LLgen. The new
target is more convenient for those who build the ACK but don't build
and install a separate LLgen.
This causes clang to give fewer warnings of implicit declarations of
functions.
In mach/pdp/cv/cv.c, rename wr_int2() to cv_int2() because it
conflicts with wr_int2() in <object.h>.
In util/ack, rename F_OK to F_TRANSFORM because it conflicts with F_OK
for access() in <unistd.h>.
+ Addition of function prototypes and include files.
+ Change function definitions to ANSI C style.
- Remove support for generating K&R code.
- Remove mkstemp and replace by tmpnam (more portable but less safe)
In many systems, malloc() can allocate outside the brk area. The
calculation with sbrk() misses those allocations. When LLgen or ncgg
reported the memory usage, the value was probably too low.
Add USEMALLOC and enable it by default. You can switch back to brk()
by removing `#define USEMALLOC` in memory.c.
USEMALLOC tells the allocator to use malloc() and realloc(), not
brk(). This might help systems where brk() doesn't work, or where
malloc() can allocate outside the brk area.
My build shows no changes in share/ack/examples (except hilo_bas.*).
Option -u was passing an offset from modulptr(0) in ALLOMODL to the
string in argv. If entername() would move ALLOMODL to make room in
ALLOGCHR, then the offset would become invalid, so the string would
get lost. This fix copies the string into ALLOMODL.
This was often not a problem because the initial size of ALLOGCHR in
mach.h is probably large enough for -u. This became a problem when I
caused the initial allocations to fail, and then only because the B
runtime uses -u.
Also move the declarations of `incore` and `core_alloc` to "memory.h".
Also correct SYMDEBUG to SYMDBUG. (I don't know if SYMDBUG works
because our build system never defines it.)
ind_t becomes an alias of size_t. ind_t becomes unsigned, so I edit
some code that was using negative ind_t. Some casts disappear, like
(long)sizeof(...) because the size is already a size_t. There are
changes to overflow checks. Callers with a size too big for size_t
must check it before calling the memory allocator. An overflow check
of BASE + incr in memory.c sbreak() now happens on all platforms, not
only when a pointer is smaller than a long.
My build shows no changes in share/ack/examples (except hilo_bas.*
changing with every build).
Remove some declarations (not all correct) and #include <errno.h>,
<time.h>, and <unistd.h> to get the correct declarations.
Disable mount(2), umount(2), and stime(2) because BSD (around
4.3BSD-Reno) lost compatibility with these Unix v7 functions.
em libmon vanished decades ago (or never existed), and also ass appears to have
a different idea of what the em opcodes are to everything else and gets
confused.
CS eliminates outer expressions before inner ones, as `x * y * z`
before `x * y`. It does this by reversing the order of expressions in
the code. This almost always works, but it sometimes doesn't work if
a STI changes the value number of a LOI. In code like `expr1 LOI
expr2 STI expr2 LOI`, CS might eliminate the inner `expr2` before the
outer `expr2 LOI`. This caused a read after free because the
occurrence of `expr2 LOI` pointed to the eliminated lines of `expr2`.
This bug went unnoticed until my recent changes caused CS to crash
with a double free. I did not get the crash in OpenBSD, but I saw the
crash in Travis, then David Given reproduced the crash in Linux. See
the discussion in https://github.com/davidgiven/ack/pull/73
the -U command line option, and one via file scanning. Turns out only the
second would increment the number of global names, so adding names with -U
would cause names found via scanning to fall off the end of the list! This
wouldn't cause linker errors because fixups don't use the list, but would cause
the generated symbol table in the output to be incorrect.
Enable this in CS for PowerPC; disable it for all other machines.
PowerPC has no remainder instruction; the back end uses division to
compute remainder. If CS finds both a / b and a % b, then CS now
rewrites a % b as a - b * (a / b) and computes a / b only once. This
removes an extra division in the PowerPC code, so it saves both time
and space.
I have not considered whether to enable this optimization for other
machines. It might be less useful in machines with a remainder
instruction. Also, if a % b occurs before a / b, the EM code gets a
DUP. PowerPC ncg handles this DUP well; other back ends might not.
In ego, the CS phase may convert a LAR/SAR to AAR LOI/STI so it can
optimize multiple occurrences of AAR of the same array element. This
conversion should not happen if it would LOI/STI a large or unknown
size.
cs_profit.c okay_lines() checked the size of each occurrence of AAR
except the first. If the first AAR was the implicit AAR in a LAR/SAR,
then the conversion happened without checking the size. For unknown
size, this made a bad LOI -1 or STI -1. Fix by checking the size
earlier: if a LAR/SAR has a bad size, then don't enter it as an AAR.
This Modula-2 code showed the bug. Given M.def:
DEFINITION MODULE M;
TYPE S = SET OF [0..95];
PROCEDURE F(a: ARRAY OF S; i, j: INTEGER);
END M.
and M.mod:
(*$R-*) IMPLEMENTATION MODULE M;
FROM SYSTEM IMPORT ADDRESS, ADR;
PROCEDURE G(s: S; p, q: ADDRESS; t: S); BEGIN
s := s; p := p; q := q; t := t;
END G;
PROCEDURE F(a: ARRAY OF S; i, j: INTEGER); BEGIN
G(a[i + j], ADR(a[i + j]), ADR(a[i + j]), a[i + j])
END F;
END M.
then the bug caused an error:
$ ack -mlinuxppc -O3 -c.e M.mod
/tmp/Ack_b357d.g, line 57: Argument range error
The bug had put LOI -1 in the code, then em_decode got an error
because -1 is out of range for LOI.
Procedure F has 4 occurrences of `a[i + j]`. The size of `a[i + j]`
is 96 bits, or 12 bytes, but the EM code hides the size in an array
descriptor, so the size is unknown to CS. The pragma `(*$R-*)`
disables a range check on `i + j` so CS can work. EM uses AAR for the
2 `ADR(a[i + j])` and LAR for the other 2 `a[i + j]`. EM pushes the
arguments to G in reverse order, so the last `a[i + j]` in Modula-2 is
the first LAR in EM.
CS found 4 occurrences of AAR. The first AAR was an implicit AAR in
LAR. Because of the bug, CS converted this LAR 4 to AAR 4 LOI -1.
