The new features are the hi16/lo16 and ha16/lo16 syntax for
relocations, and the extended mnemonics like "blr".
Use ha16/lo16 to load some double floats with 2 instructions (lis/lfd)
instead of 3 (lis/ori/lfd).
Use the extended names for branches, comparisons, and bit rotations,
so I can more easily read the code. The new names often encode the
same machine instructions as the old names, except in a few places
where I changed the instructions.
Stop using andi. when we don't need to set cr0. In inn.s, I change
andi. to extrwi to extract the same bits. In los.s and sts.s, I
change "andi. r3, r3, ~3" to "clrrwi r3, r3, 2". This avoids setting
cr0 and also stops clearing the high 16 bits of r3.
In csa.s, los.s, sts.s, I change some comparisons and right shifts
from signed to unsigned (cmplw, cmplwi, srwi), because the sizes are
unsigned. In inn.s, the right shift can be signed (sraw) or unsigned
(srw), but I use srw because we don't need the carry bit.
In fef8.s, I save an instruction by using rlwinm instead of addis/andc
to rlwinm to clear a field. The code no longer kills r7. In both
fef8.s and fif8.s, I remove the list of killed registers.
Also remove some whitespace from ends of lines.
Linux passes the arguments in registers, but our compiler expects
arguments on the stack. Signal handlers got garbage instead of the
signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c,
need the correct signal number.
I write a "bridge" in PowerPC assembly that moves the arguments to the
stack. I put the bridge in sigaction(), so I provide a signal() that
calls sigaction(). I remove the *.c glob or wildcard from build.lua,
so linuxppc only compiles its own signal.c, not the other signal.c for
linux386 and linux68k.
My bridge uses sigprocmask(), so I also add sigprocmask(). Because
linux386 and linux68k use globs, they also get sigprocmask(). I sync
the header files so all three Linux platforms declare execve(),
sigprocmask(), and unlink(), but not remove(), because we have
remove() in <stdio.h>.
I am using sigaction.s to test some features that we recently added to
our PowerPC assembler. These are the "hi16[...]" and "lo16[...]"
syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
Also make a few changes to basic mnemonics. Fix typo in name of the
basic "creqv". Add the basic "addc" and relatives, because it would
be odd to have the extended "subc" without "addc". Fix the basic
"rldicl", "rldicr", "rldic", "rldimi" to correctly encode the 6-bit MB
field. Fix "slw" and relatives to correctly swap their RA and RS
operands.
Add many, but not all, of the extended mnemonics from IBM's Power ISA
Version 2.06 Book I Appendix E. (I used 2.06, published 2009, just
because I already had the PDF of it.) This commit includes mnemonics
for branching, subtraction, traps, bit rotation, and a few others,
like "mflr" and "nop". The assembler now understands branches like
`beq cr7, label` and bit shifts like `slwi r7, r7, 2`. These encode
the same machine instructions as the basic "bc" and "rlwinm".
Some operands to basic names become optional. The assembler no longer
requires the level in "sc" or the branch hint in "bcctr" and "bclr";
they default to zero. Some extended names take an optional branch
hint or condition register.
Some extended names are still missing. I don't provide names with
static branch prediction, like "beq+" or "bge-", because the assembler
parses '+' and '-' as operators, not as part of an instruction name.
I also don't provide some names that 2.06 has for moving to or from
the condition register or some special purpose registers, names like
"mtcr" or "mfuamr".
This commit also deletes some unused tokens and one unused yacc rule.
This commit slightly improves the formatting of the manuals. My
OpenBSD machine uses mandoc(1) to format manuals. I check the manuals
with `mandoc -T lint` and fix most of the warnings. I also make
other changes where mandoc didn't warn me.
roff(7) says, "Each sentence should terminate at the end of an input
line," but we often forgot this rule. I insert some newlines after
sentences that had ended mid-line.
roff(7) also says that blank lines "are only permitted within literal
contexts." I delete blank lines. This removes some extra blank lines
from mandoc's output. If I do want a blank line in the output, I call
".sp 1" to make it in man(7). If I want a blank line in the source,
but not the output, I put a plain dot "." so roff ignores it.
Hyphens used for command-line options, like \-a, should be escaped by
a backslash. I insert a few missing backslashes.
mandoc warns if the date in .TH doesn't look like a date. Our manuals
had a missing date or the RCS keyword "$Revision$". Git doesn't
expand RCS keywords. I put in today's date, 2017-01-18.
Some manuals used tab characters in filled mode. That doesn't work.
I use .nf to turn off filled mode, or I use .IP in man(7) to make the
indentation without a tab character.
ack(1) defined a macro .SB but never used it, so I delete the
definition. I also remove a call to the missing macro .RF.
mandoc warns about empty paragraphs. I deleted them. mandoc also
warned about these macro pairs in anm(1):
.SM
.B text
The .SM did nothing because the .B text is on a different line. I
changed each pair to .SB for small bold text.
I make a few other small changes.
I need this so I can add more %token lines to mach/powerpc/as/mach2.c
The assembler's tempfile encoded each token in a byte. This only
worked with tokens 0 to 127 and 256 and 383. If a token 384 or higher
existed, the assembler stopped working. I need tokens 384 and higher.
I change the token encoding to a 2-byte little-endian integer. I also
change a byte in the string encoding.
---snip---
The ELF spec at http://www.sco.com/developers/gabi/ says, "In each
symbol table, all symbols with STB_LOCAL binding precede the weak and
global symbols," and that sh_info is the index of the first non-local
symbol.
I was mixing local and global symbols and setting sh_info to zero. I
also forgot to set the type of the .shstrtab section.
---snip---
See issue #1 (https://github.com/davidgiven/ack/issues/1). The file
mach/proto/as/comm2.y goes through cpp twice. The _include macro,
defined in comm2.y and used in comm0.h, delays the inclusion of system
header files. The inclusion of <stdint.h> wasn't delayed. This
caused multiple inclusions of <sys/_types.h> in FreeBSD and
<machine/_types.h> in OpenBSD.
Use _include to delay <stdint.h>. Also use _include for "arch.h" and
"out.h", because h/out.h includes <stdint.h> and h/arch.h might
include it in the future.
Sort the system includes in comm0.h by moving them up to be with
<stdint.h>. Must include <stdint.h> before "mach0.c", because
mach/powerpc/as/mach0.c needs it. Must include "mach0.c" before
checking ASLD.
In my OpenBSD/amd64 system, the code becomes
if (0)
outname.on_valu &= ~(((0xFFFFFFFF)<<32)<<32);
The 0xFFFFFFFF is a 32-bit int, so the left shift by 32 is out of
range and causes the gcc warning.
The intent might be to clear any sign-extended bits, if the assignment
outname.on_valu = valu did sign extension. Old C had no unsigned
long, so .on_valu would have been long. The code is obsolete because
h/out.h now declares .on_valu as uint32_t.
possible values. Add the PowerPC ncg and mcg backend support to let the test
actually run, including modifying a bunch of PowrePC libem functions so that
they can be called from both ncg and mcg.
assembler directives, ha16() and has16(), for the upper half; has16() applies
the sign adjustment. .powerpcfixup is now gone, as we generate the relocation
in ha*() instead. Add special logic to the linker for undoing and redoing the
sign adjustment when reading/writing fixups. Tests still pass.