corresponding invocation in the ncg table so the same helpers can be used for
both mcg and ncg. Add a new IR opcode, FARJUMP, which jumps to a helper
function but saves volatile registers.
unlink("core") doesn't work with OpenBSD, where core dumps have names
like "ncg.core". Users who don't want core dumps can turn them off
with "ulimit -c 0" in sh(1). Then the system doesn't write a core
dump. That's better than writing core then unlinking it.
This commit changes how ack(1) parses backslashes in its descr files.
Before this commit, ack set the high bit of each character escaped by
a backslash, and later cleared all high bits in command arguments, but
this lost the high bits in non-ASCII filenames. After this commit,
ack keeps backslashes in strings while processing them. Functions
scanvars(), scanexpr(), doassign(), unravel(), addargs() now
understand backslashes. I remove from ack_basename() the warning
about non-ASCII characters.
This commit makes some incompatible changes for backslashes in descr
files. None of our descr files uses backslashes, except for those
backslashes that continue lines, and there are no changes for those
backslashes. The problem with non-ASCII filenames had its cause in a
feature that we weren't using.
With this commit, ack now understands backslashes after the = sign in
both "var NAME=value" and "mapflag -flag NAME=value". Before, ack
never scanned backslashes in "var" lines, so "var A=\{B}" failed to
prevent expansion of B. Now it does. Before, ack did scan for
backslashes in the "-flag NAME=" part of "mapflag" lines. Now it
doesn't, so it is no longer possible to map a flag that contains a
literal space, tab, or star "*".
I removed the expansion of "{{" to "{". One can use "\{" for a
literal "{", and "\{" now works in "var" lines. Before and now, ack
never expanded "{" in flags for "mapflag", so the correct way to map a
literal flag "-{" remains "mapflag -{ ...", not "mapflag -{{ ...".
(The other way "mapflag -\{ ..." stops working with this commit.)
Backslashes in strange places, like "{NA\ME}", probably have different
behavior now.
Backslashes in "program" lines now work. Before, ack scanned for
backslashes there but forgot to clear the high bits later.
Escaping < or > as \< or \> now works, and prevents substitution of
the input or output file paths. Before, ack only expanded the first <
or > in each argument. Now, it expands every unescaped < or > in an
argument, but this is an accident of how I rewrote the code. I don't
suggest to put more than one each of < or > in a command. The code no
longer optimizes away its recursive calls when the argument is "<".
The code continues to set or clear the high bit NO_SCAN on the first
characters of flags. This doesn't seem to be a problem, because flags
usually begin with an ASCII hyphen '-'.
If fork() fails, then report a fatal error. Don't spin the cpu
retrying fork() until it succeeds. It can fail when we reach a limit
on the number of processes. Spinning on the cpu would slow down other
processes when we want them to exit. This would get bad if we had a
parallel build with multiple ack processes spinning.
new= newvar(name) takes ownership of the string and might free its
memory. Don't print name. Do print new->v_name.
Also #include <string.h> for strcmp().
Declare most functions before using them. I declare some functions in
ack.h and some in trans.h (because trans.h declares type trf). I
leave declarations of scanb() and scanvars() in .c files because they
need type growstring. (I can't #include "grows.h" in another header
file as long as grows.h doesn't guard against multiple inclusion.)
Functions used within one file become static. I remove a few tiny
functions. I move a few functions or declarations to more convenient
places. Some functions now return void instead of a garbage int.
I feel that keyword "register" is obsolete, so I removed it from where
I was editing. This commit doesn't touch mktables.c
register 'type'; now use int/float/long/double throughout to identify
registers. Lots of register allocator tweaks and table bugfixes --- we now get
through the dreading Mathlib.mod!
and epilogues. mcgg now exports some useful data as headers. Start factoring
out some of the architecture-specific bits into an architecture-specific file.
attributes when allocating. Unfortunately, backward edges don't work (because
the limited def-use chain stuff doesn't work across basic blocks). Needs more
thought.
turned into generic ones (as they'll be useful everywhere). Node arguments for
predicates require the '%' prefix for consistency. Hex numbers are permitted.
This feature has never been used since its introduction, more than 3
years ago, in David Given's commit c93cb69 of May 8, 2013. The commit
was for "PowerPC and M68K work". I am not undoing the entire commit.
I am only removing the stackadjust and stackoffset() feature.
This commit removes the feature from my branch kernigh-linuxppc. This
removal includes the mach/proto/ncg parts. The default branch already
removed most of the feature, but kept the mach/proto/ncg parts. That
removal happened in commit 81778b6 of May 13, 2013 (which was a merge;
git diff af0dede81778b6). The branch dtrg-experimental-powerpc
merged the default branch but without the removal. That merge was
commit 4703db0f of Sep 15, 2016 (git diff 8c94b134703db0). My branch
kernigh-linuxppc is off branch dtrg-experimental-powerpc, so I can no
longer get the removal by merging default.
David Given described the stackadjust feature in
https://sourceforge.net/p/tack/mailman/message/30814691/
The instruction stackadjust would add a value to the offset, and the
function stackoffset() would return this offset. One would use this
to track sp - fp, then omit the frame pointer by not keeping fp in a
register.
mcg can track individual hop inputs and outputs (needed for live range
analysis!); the register allocator now puts the basic blocks into the right
order in preparation for live range analysis.
