Reference the 80386 compiler documentation now that the
documentation for the 68020 is offline.
R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7127053
Changeset f483bfe81114 moved ELF generation to the architecture
independent code and in doing so added a Section* to the Sym
type and an Elf64_Shdr* to the Section type.
This caused the Plan 9 compilers to complain about incompatible
type signatures in the many files that reference the Sym type.
R=rsc, dave
CC=golang-dev
https://golang.org/cl/7057058
There's no b in race detector.
The new flag matches the one in the go command
(go test -race math).
R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/7072043
This CL adds a flag parser that matches the semantics of Go's
package flag. It also changes the linkers and compilers to use
the new flag parser.
Command lines that used to work, like
8c -FVw
6c -Dfoo
5g -I/foo/bar
now need to be split into separate arguments:
8c -F -V -w
6c -D foo
5g -I /foo/bar
The new spacing will work with both old and new tools.
The new parser also allows = for arguments, as in
6c -D=foo
5g -I=/foo/bar
but that syntax will not work with the old tools.
In addition to matching standard Go binary flag parsing,
the new flag parser generates more detailed usage messages
and opens the door to long flag names.
The recently added gc flag -= has been renamed -complete.
R=remyoudompheng, daniel.morsing, minux.ma, iant
CC=golang-dev
https://golang.org/cl/7035043
More cleanup in preparation for fixing issue 4069.
This CL replaces the three nearly identical copies of the
asmb ELF code with a single asmbelf function in elf.c.
In addition to the ELF code movement, remove the elfstr
array in favor of a simpler lookup, and identify sections by
name throughout instead of computing fragile indices.
The CL also replaces the three nearly identical copies of the
genasmsym code with a single genasmsym function in lib.c.
The ARM linker still compiles and generates binaries,
but I haven't tested the binaries. They may not work.
R=ken2
CC=golang-dev
https://golang.org/cl/7062047
The Plan 9 symbol table format defines big-endian symbol values
for portability, but we want to be able to generate an ELF object file
and let the host linker link it, as part of the solution to issue 4069.
The symbol table itself, since it is loaded into memory at run time,
must be filled in by the final host linker, using relocation directives
to set the symbol values. On a little-endian machine, the linker will
only fill in little-endian values during relocation, so we are forced
to use little-endian symbol values.
To preserve most of the original portability of the symbol table
format, we make the table itself say whether it uses big- or
little-endian values. If the table begins with the magic sequence
fe ff ff ff 00 00
then the actual table begins after those six bytes and contains
little-endian symbol values. Otherwise, the table is in the original
format and contains big-endian symbol values. The magic sequence
looks like an "end of table" entry (the fifth byte is zero), so legacy
readers will see a little-endian table as an empty table.
All the gc architectures are little-endian today, so the practical
effect of this CL is to make all the generated tables little-endian,
but if a big-endian system comes along, ld will not generate
the magic sequence, and the various readers will fall back to the
original big-endian interpretation.
R=ken2
CC=golang-dev
https://golang.org/cl/7066043
A few USED(xxx) additions and a couple of deletions of variable
initialisations that go unused. One questionable correction,
mirrored in 8l/asm.c, where the result of invocation of a function
shouldn't be used.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6736054
The 0-length part is fine, but some callers that write 0 bytes
also pass nil as the data pointer, and the Plan 9 kernel kills the
process with 'invalid address in sys call' in that case.
R=ken2
CC=golang-dev
https://golang.org/cl/6862051
In order to add these, we need to be able to find references
to such types that already exist in the binary. To do that, introduce
a new linker section holding a list of the types corresponding to
arrays, chans, maps, and slices.
To offset the storage cost of this list, and to simplify the code,
remove the interface{} header from the representation of a
runtime type. It was used in early versions of the code but was
made obsolete by the kind field: a switch on kind is more efficient
than a type switch.
In the godoc binary, removing the interface{} header cuts two
words from each of about 10,000 types. Adding back the list of pointers
to array, chan, map, and slice types reintroduces one word for
each of about 500 types. On a 64-bit machine, then, this CL *removes*
a net 156 kB of read-only data from the binary.
This CL does not include the needed support for precise garbage
collection. I have created issue 4375 to track that.
This CL also does not set the 'algorithm' - specifically the equality
and copy functions - for a new array correctly, so I have unexported
ArrayOf for now. That is also part of issue 4375.
Fixes#2339.
R=r, remyoudompheng, mirtchovski, iant
CC=golang-dev
https://golang.org/cl/6572043
This is an experiment in static analysis of Go programs
to understand which struct fields a program might use.
It is not part of the Go language specification, it must
be enabled explicitly when building the toolchain,
and it may be removed at any time.
After building the toolchain with GOEXPERIMENT=fieldtrack,
a specific field can be marked for tracking by including
`go:"track"` in the field tag:
package pkg
type T struct {
F int `go:"track"`
G int // untracked
}
To simplify usage, only named struct types can have
tracked fields, and only exported fields can be tracked.
The implementation works by making each function begin
with a sequence of no-op USEFIELD instructions declaring
which tracked fields are accessed by a specific function.
After the linker's dead code elimination removes unused
functions, the fields referred to by the remaining
USEFIELD instructions are the ones reported as used by
the binary.
The -k option to the linker specifies the fully qualified
symbol name (such as my/pkg.list) of a string variable that
should be initialized with the field tracking information
for the program. The field tracking string is a sequence
of lines, each terminated by a \n and describing a single
tracked field referred to by the program. Each line is made
up of one or more tab-separated fields. The first field is
the name of the tracked field, fully qualified, as in
"my/pkg.T.F". Subsequent fields give a shortest path of
reverse references from that field to a global variable or
function, corresponding to one way in which the program
might reach that field.
A common source of false positives in field tracking is
types with large method sets, because a reference to the
type descriptor carries with it references to all methods.
To address this problem, the CL also introduces a comment
annotation
//go:nointerface
that marks an upcoming method declaration as unavailable
for use in satisfying interfaces, both statically and
dynamically. Such a method is also invisible to package
reflect.
Again, all of this is disabled by default. It only turns on
if you have GOEXPERIMENT=fieldtrack set during make.bash.
R=iant, ken
CC=golang-dev
https://golang.org/cl/6749064
compiler_rt introduces a weak and hidden symbol compilerrt_abort_impl
into our pre-linked _all.o object, we have to handle it.
Fixes#4273.
R=iant, rsc, r
CC=golang-dev
https://golang.org/cl/6783050
Check for specific, important misalignment in garbage collector.
Not a complete fix for issue 599 but an important workaround.
Update #599.
R=golang-dev, iant, dvyukov
CC=golang-dev
https://golang.org/cl/6641049
1. R_ARM_CALL can also be used to call a PLT entry
2. add support for R_ARM_PC24 and R_ARM_JUMP24
3. refactor, remove D_PLT32 in favor of D_CALL
Fixes#4006.
R=rsc, dave
CC=fullung, golang-dev
https://golang.org/cl/6622057
Use explicit IntSize constant instead of 4.
This CL does not change the meaning of int, but it should make
the eventual change of the meaning of int on amd64 a bit
smoother.
Update #2188.
R=ken, dave
CC=golang-dev
https://golang.org/cl/6554076
OpenBSD now requires ELF binaries to have a PT_NOTE that identifies
it as an OpenBSD binary. Refactor the existing NetBSD ELF signature
code and implement support for OpenBSD ELF signatures.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6489131
We use pkg path instead of file name (which contains $WORK) in section symbols names.
R=golang-dev, fullung, rsc, iant
CC=golang-dev
https://golang.org/cl/6445085
This is the second part of a bigger change that adds data race detection feature:
https://golang.org/cl/6456044
This change makes the linker emit dependency on runtime/race package when supplied with -b flag.
R=rsc, minux.ma
CC=golang-dev
https://golang.org/cl/6488074
This fixes a problem with ELF tools thinking they know the
format of the symbol table, as we do not use any of the
standard formats for that table.
This change will probably annoy the Plan 9 users, but I
believe there are other incompatibilities already that mean
they have to use a Go-specific nm.
Fixes#3473.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/6500117
To make it more compliant.
This won't affect the behavior of running on OABI-only kernels.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/6475044
The last fix was wrong w.r.t C's operator precedence,
and it also failed to really skip the NONE relocation.
The offending R_386_NONE relocation is a absolute
relocation in section .eh_frame.
TBR=golang-dev
CC=golang-dev
https://golang.org/cl/6463058
PAX systems are Linux systems that are more paranoid about memory permissions.
These flags tell them to relax when running Go binaries.
Fixes#47.
R=iant
CC=golang-dev
https://golang.org/cl/6326054
16 seems pretty standard on x86 for function entry.
I don't know if ARM would benefit, so I used just 4
(single instruction alignment).
This has a minor absolute effect on the current timings.
The main hope is that it will make them more consistent from
run to run.
benchmark old ns/op new ns/op delta
BenchmarkBinaryTree17 4222117400 4140739800 -1.93%
BenchmarkFannkuch11 3462631800 3259914400 -5.85%
BenchmarkGobDecode 20887622 20620222 -1.28%
BenchmarkGobEncode 9548772 9384886 -1.72%
BenchmarkGzip 151687 150333 -0.89%
BenchmarkGunzip 8742 8741 -0.01%
BenchmarkJSONEncode 62730560 65210990 +3.95%
BenchmarkJSONDecode 252569180 249394860 -1.26%
BenchmarkMandelbrot200 5267599 5273394 +0.11%
BenchmarkRevcomp25M 980813500 996013800 +1.55%
BenchmarkTemplate 361259100 360620840 -0.18%
R=ken2
CC=golang-dev
https://golang.org/cl/6244066
On NetBSD a cgo enabled binary has more than 32 sections - bump NSECTS
so that we can actually link them successfully.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6261052
Plan 9 versions for amd64 have 2 megabyte pages.
This also fixes the logic for 32-bit vs 64-bit Plan 9,
making 64-bit the default, and adds logic to generate
a symbols table.
R=golang-dev, rsc, rminnich, ality, 0intro
CC=golang-dev, john
https://golang.org/cl/6218046
CL 5823055 removed a line introduced in Linux/ARM cgo support.
Because readsym() now returns nil for "$a", "$d" mapping symbols,
no matter the settings of `needSym', we still have to guard against
them in ldelf().
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/6220073
Introduce a newsym() to cmd/lib.c to add a symbol but don't add
them to hash table.
Introduce a new bit flag SHIDDEN and bit mask SMASK to handle hidden
and/or local symbols in ELF symbol tables. Though we still need to order
the symbol table entries correctly.
Fix for issue 3261 comment #9.
For CL 5822049.
R=iant, rsc
CC=golang-dev
https://golang.org/cl/5823055
ld -r could generate multiple section symbols for the same section,
but with different values, we have to take that into account.
Fixes#3322.
Part of issue 3261.
For CL 5822049.
R=golang-dev, iant, rsc, iant
CC=golang-dev
https://golang.org/cl/5823059
Some newer Linux distributions (Ubuntu ARM at least) use a new multiarch
directory organization, where dynamic linker is no longer in the hardcoded
path in our linker.
For example, Ubuntu 12.04 ARM hardfloat places its dynamic linker at
/lib/arm-linux-gnueabihf/ld-linux.so.3
Ref: http://lackof.org/taggart/hacking/multiarch/
Also, to support Debian GNU/kFreeBSD as a FreeBSD variant, we need this capability, so it's part of issue 3533.
This CL add a new pragma (#pragma dynlinker "path") to cc.
R=iant, rsc
CC=golang-dev
https://golang.org/cl/6086043
Part 1 of CL 5601044 (cgo: Linux/ARM support)
Limitation: doesn't support thumb library yet.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/5991065
1. consistent usage section (go tool xxx)
2. reformat cmd/ld document with minor correction
document which -H flags are valid on which ld
document -d flag can't be used on Windows.
document -Hwindowsgui
R=golang-dev, r, rsc
CC=golang-dev
https://golang.org/cl/5782043
We were not aligning the code size,
so read-only data, which follows in the same
segment, could be arbitrarily misaligned.
Fixes#2506.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/5693055
cc: add #pragma textflag to set it
runtime: mark mheap to go into noptr-bss.
remove special case in garbage collector
Remove the ARM from.flag field created by CL 5687044.
The DUPOK flag was already in p->reg, so keep using that.
Otherwise test/nilptr.go creates a very large binary.
Should fix the arm build.
Diagnosed by minux.ma; replacement for CL 5690044.
R=golang-dev, minux.ma, r
CC=golang-dev
https://golang.org/cl/5686060
The garbage collector can avoid scanning this section, with
reduces collection time as well as the number of false positives.
Helps a little bit with issue 909, but certainly does not solve it.
R=ken2
CC=golang-dev
https://golang.org/cl/5671099
unsafe: delete Typeof, Reflect, Unreflect, New, NewArray
Part of issue 2955 and issue 2968.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5650069
To allow these types as map keys, we must fill in
equal and hash functions in their algorithm tables.
Structs or arrays that are "just memory", like [2]int,
can and do continue to use the AMEM algorithm.
Structs or arrays that contain special values like
strings or interface values use generated functions
for both equal and hash.
The runtime helper func runtime.equal(t, x, y) bool handles
the general equality case for x == y and calls out to
the equal implementation in the algorithm table.
For short values (<= 4 struct fields or array elements),
the sequence of elementwise comparisons is inlined
instead of calling runtime.equal.
R=ken, mpimenov
CC=golang-dev
https://golang.org/cl/5451105
Equality on structs will require arbitrary code for type equality,
so change algorithm in type data from uint8 to table pointer.
In the process, trim top-level map structure from
104/80 bytes (64-bit/32-bit) to 24/12.
Equality on structs will require being able to call code generated
by the Go compiler, and C code has no way to access Go return
values, so change the hash and equal algorithm functions to take
a pointer to a result instead of returning the result.
R=ken
CC=golang-dev
https://golang.org/cl/5453043
This CL grew the archive file name length from 16 to 64:
changeset: 909:58574851d792
user: Russ Cox <rsc@golang.org>
date: Mon Oct 20 13:53:56 2008 -0700
Back then, every x.go file in a package became an x.6 file
in the archive. It was important to be able to allow the
use of long Go source file names, hence the increase in size.
Today, all Go source files compile into a single _go_.6 file
regardless of their names, so the archive file name length
no longer needs to be long. The longer name causes some
problems on Plan 9, where the native archive format is the
same but with 16-byte names, so revert back to 16.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5333050
Move string table to the end of the __LINKEDIT segment.
This change allows Apple's codesign(1) utility to successfully sign
Go binaries, as long as they don't contain DWARF data (-w flag to
8l/6l). This is because codesign(1) expects the string table to be
the last part of the file.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5271050
The Windows signtool.exe thinks our binaries are 'invalid
Win32 programs' unless the PE linker version field is 3.0
or greater.
This minor change makes it possible to successfully sign
gc-built binaries on Windows.
R=golang-dev, alex.brainman, rsc
CC=golang-dev
https://golang.org/cl/5268045
The map implementation was using the C idiom of using
a pointer just past the end of its table as a limit pointer.
Unfortunately, the garbage collector sees that pointer as
pointing at the block adjacent to the map table, pinning
in memory a block that would otherwise be freed.
Fix by making limit pointer point at last valid entry, not
just past it.
Reviewed by Mike Burrows.
R=golang-dev, bradfitz, lvd, r
CC=golang-dev
https://golang.org/cl/5158045
The Go version has 64 character long section names; originally,
in Plan 9, the limit was 16. To provide compatibility, this
change allows the input length to be either the target length
or the earlier option. The section name is extended with spaces
where required.
This has been tested to work without regressions in the
Go environment, testing the older alternative has not been
possible yet.
R=rsc
CC=golang-dev
https://golang.org/cl/4650071
The EXTERN lines in elf.h already define these.
That's not a problem for most C compilers, but
apparently it is for some copies of the OS X linker.
Fixes#2167.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/4936044
ld/data.c:
. Format specifier with corresponding cast to cater for all
architectures (llux and vlong).
ld/ldelf.c:
ld/ldmacho.c:
. Missing "pn" argument in diag() calls.
ld/ldpe.c:
. Dropped "sym->sectnum" in diag() call.
. Typo in a comment.
ld/lib.h:
. Added varargck pragma for "O".
R=rsc
CC=golang-dev
https://golang.org/cl/4749042
The dynamic ELF sections were pointing to the proper data,
but that data was already owned by the rodata and text sections.
Some ELF references explicitly prohibit multiple sections from
owning the same data, and strip behaves accordingly.
The data for these sections was moved out and their ranges are
now owned by their respective sections. This change makes strip
happy both with and without -s being provided at link time.
A test was added in debug/elf to ensure there are no regressions
on this area in the future.
Fixes#1242.
Fixes#2022.
NOTE: Tested on Linux amd64/386/arm only.
R=rsc
CC=golang-dev
https://golang.org/cl/4808043
Reduces number of write+seek's from 88516 to 2080
when linking godoc with 6l.
Thanks to Alex Brainman for pointing out the
many small writes.
R=golang-dev, r, alex.brainman, robert.hencke
CC=golang-dev
https://golang.org/cl/4743043
The gosymtab and gopclntab sections were pointing to the proper
data, but that data was already owned by the rodata section.
Some ELF references explicitly prohibit multiple sections from
owning the same data, and strip behaves accordingly.
The data for these sections was moved to after rodata, and the
gosymtab and gopclntab sections now own their respective ranges.
This change makes strip happy both with and without -s being
provided at link time. Note that it won't remove these sections
because they are still allocated, and that's by design since
they are necessary at runtime for generating proper backtraces
and similar introspection operations.
Unlike the previous behavior, -s will now maintain zero-sized
gosymtab and gopclntab sections. This makes the implementation
slightly cleaner.
Fixes#1242.
NOTE: Tested on Linux amd64/386/arm only.
R=ality, rsc
CC=golang-dev
https://golang.org/cl/4639077
This prevents ld from generating zeroed symtab entries for
sections that aren't going to be generated because dynamic
linkage has been disabled (-d was used or no dynamic libs
were seen). Even though they were not explicitly added by
doelf, the section creation process was making them
reachable again.
The windows head is being disconsidered for this because
apparently it's not taking into account debug['d'].
This makes elflint 0.1% happier.
R=golang-dev, rsc, gustavo
CC=golang-dev
https://golang.org/cl/4638050
Once these changes are effected, it is possible to construct
"8l" native on a (386?) Plan 9 system, albeit with assistance
from modules such as mkfiles that are not (yet) included in any
public patches.
8l/asm.c:
. Corrected some format qualifiers.
8l/list.c:
. Cast a print() argument to (int) to match the given format.
It may be possible to change the format (%R), but I have not
looked into it.
8l/obj.c:
. Removed some unused code.
8l/span.c:
. Removed unnecessary incrementation on "bp".
. Corrected some format qualifiers.
ld/data.c:
. Corrected some format qualifiers.
. Cast print argument to (int): used as field size.
. Use braces to suppress warning about empty if() statements.
ld/dwarf.c:
. Trivial spelling mistake in comment.
ld/ldelf.c:
. Added USED() statements to silence warnings.
. Dropped redundant address (&) operators.
. corrected some format qualifiers.
. Cast to (int) for switch selection variable.
ld/macho.c:
. Added USED() statements to silence warnings.
ld/ldpe.c:
. Added USED() statements to silence warnings.
. More careful use of "sect" variable.
. Corrected some format qualifiers.
. Removed redundant assignments.
. Minor fix dropped as it was submitted separately.
ld/pe.c:
. Dropped <time.h> which is now in <u.h>.
. Dropped redundant address (&) operators.
. Added a missing variable initialisation.
ld/symtab.c:
. Added USED() statements to silence warnings.
. Removed redundant incrementation.
. Corrected some format qualifiers.
All the above have been tested against a (very) recent release
and do not seem to trigger any regressions.
All review suggestions have been incorporated.
R=rsc
CC=golang-dev
https://golang.org/cl/4633043
The "elf.h" header changes involve only comments, the released
Plan 9 C preprocessing function does not cope with multiline
comments following the #define keyword. All multiline comments
have been moved to the line above the associated definition.
Sigh! Fixing the Plan 9 compiler is not an option.
<time.h> does not exist in the Plan 9 Native library. I have
moved it from src/cmd/ld/pe.h to include/u.h. RSC correctly points
out that this copy of <u.h> is not the one used to compile the
Go release on Plan 9 platforms.
R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4574042
Makes it possible for older tools like objdump to find the filenames,
fixes objdump -d -l --start-address=0x400c00 --stop-address=0x400c36 6.out
fixes#1950
R=rsc
CC=golang-dev
https://golang.org/cl/4609043
I started looking at this code because the nm in GNU
binutils was ignoring the first symbol in the .symtab
section. Apparently, the System V ABI reserves the
first entry and requires all fields inside to be set
to zero.
The list of changes is as follows:
· reserve the first symbol entry (as noted above)
· fix the section indices for .data and .bss symbols
· factor out common code for Elf32 and Elf64
· remove the special case for elfsymo in [568]l/asm.c:/^asmb
· add the "etext" symbol in 6l
· add static symbols
R=rsc
CC=golang-dev
https://golang.org/cl/4524075
These changes are not particularly invasive and have been tested
as broadly as possible.
8l/l.h:
- #pragma varargck: added some, removed duplicates.
ld/dwarf.c:
- As Plan 9 has no NULL, changed all occurrences to nil.
- Added USED(size); where necessary.
- Added (void) argument in definition of finddebugruntimepath().
- Plan 9 compiler was complaining about multiple
assignments, repeaired by breaking up the commands.
- Correction: havedynamic = 1; restored.
ld/go.c:
- Needed USED(file); in two functions.
- Removed unused assignments flagged by the Plan 9 compiler.
ld/lib.c:
- Replaced unlink() with remove() which seems available everywhere.
- Removed USED(c4); and USED(magic) no longer required.
- Removed code flagged as unused by the Plan 9 compiler.
- Added attributes to a number of format strings.
R=rsc
CC=golang-dev
https://golang.org/cl/4435047
Reenable dwarf output on Mac.
Was writing headers but no actual dwarf data.
Fixes#1877 (accidentally).
Workaround for issue 1878.
R=lvd
CC=golang-dev
https://golang.org/cl/4515139
This was causing a panic in the reflect package
since type.* pointers with their low bits set are
assumed to have certain flags set that disallow
the use of reflection.
Thanks to Pavel and Taru for help tracking down
this bug.
R=rsc, paulzhol, taruti
CC=golang-dev
https://golang.org/cl/4511041
This change will allow to generate valid executable,
even if rsc disables dwarf generation, as it happend
at revision 9a64273f9d68.
R=rsc
CC=golang-dev, lvd, vcc
https://golang.org/cl/4425066
Static symbols were not being marked as such.
I also made the 'z' symbols use the first byte of
the name instead of an explicit NUL so that if
the symbol table format is ever changed, the only
place that would need updating is addhist().
R=rsc
CC=golang-dev
https://golang.org/cl/4366047
The list elements are already being allocated out of a
single memory buffer. We can drop the Link* pointer
following and the memory it requires, replacing it with
index operations.
The change also keeps a channel from containing a pointer
back into its own allocation block, which would create a
cycle. Blocks involved in cycles are not guaranteed to be
finalized properly, and channels depend on finalizers to
free OS-level locks on some systems. The self-reference
was keeping channels from being garbage collected.
runtime-gdb.py will need to be updated in order to dump
the content of buffered channels with the new data structure.
Fixes#1676.
R=ken2, r
CC=golang-dev
https://golang.org/cl/4411045
The ld time was dominated by symbol table processing, so
* increase hash table size
* emit fewer symbols in gc (just 1 per string, 1 per type)
* add read-only lookup to avoid creating spurious symbols
* add linked list to speed whole-table traversals
Breaks dwarf generator (no idea why), so disable dwarf.
Reduces time for 6l to link godoc by 25%.
R=ken2
CC=golang-dev
https://golang.org/cl/4383047
Fixes the broken linux/amd64 build.
The symbol table, itself a symbol, was having
its size rounded up to the nearest word boundary.
If the rounding add >7 zero bytes then it confused
the debug/gosym symbol table parser. So you've
got a 1/8 chance to hit the bug on an amd64 system.
Just started in the recent change because I fixed
the rounding to round to word boundary instead
of to 4-byte boundary.
R=r
CC=golang-dev
https://golang.org/cl/4241056
Much of the bulk of Go binaries is the symbol tables,
which give a name to every C string, Go string,
and reflection type symbol. These names are not worth
much other than seeing what's where in a binary.
This CL deletes all those names from the symbol table,
instead aggregating the symbols into contiguous blocks
and giving them the names "string.*", "go.string.*", and "type.*".
Before:
$ 6nm $(which godoc.old) | sort | grep ' string\.' | tail -10
59eda4 D string."aa87ca22be8b05378eb1c71...
59ee08 D string."b3312fa7e23ee7e4988e056...
59ee6c D string."func(*token.FileSet, st...
59eed0 D string."func(io.Writer, []uint8...
59ef34 D string."func(*tls.Config, *tls....
59ef98 D string."func(*bool, **template....
59effc D string."method(p *printer.print...
59f060 D string."method(S *scanner.Scann...
59f12c D string."func(*struct { begin in...
59f194 D string."method(ka *tls.ecdheRSA...
$
After:
$ 6nm $(which godoc) | sort | grep ' string\.' | tail -10
5e6a30 D string.*
$
Those names in the "Before" are truncated for the CL.
In the real binary they are the complete string, up to
a certain length, or else a unique identifier.
The same applies to the type and go.string symbols.
Removing the names cuts godoc by more than half:
-rwxr-xr-x 1 rsc rsc 9153405 2011-03-07 23:19 godoc.old
-rwxr-xr-x 1 rsc rsc 4290071 2011-03-07 23:19 godoc
For what it's worth, only 80% of what's left gets loaded
into memory; the other 20% is dwarf debugging information
only ever accessed by gdb:
-rwxr-xr-x 1 rsc rsc 3397787 2011-03-07 23:19 godoc.nodwarf
R=r, cw
CC=golang-dev
https://golang.org/cl/4245072
The pointer will eventually let us find *T given T.
This CL just makes room for it, always storing a zero.
R=r, r2
CC=golang-dev
https://golang.org/cl/4221046
A reference to the address of weak.foo resolves at link time
to the address of the symbol foo if foo would end up in the
binary anyway, or to zero if foo would not be in the binary.
For example:
int xxx = 1;
int yyy = 2;
int weak·xxx;
int weak·yyy;
void main·main(void) {
runtime·printf("%p %p %p\n", &xxx, &weak·xxx, &weak·yyy);
}
prints the same non-nil address twice, then 0 (because yyy is not
referenced so it was dropped from the binary).
This will be used by the reflection tables.
R=iant
CC=golang-dev
https://golang.org/cl/4223044
Fix problems found.
On amd64, various library routines had bigger
stack frames than expected, because large function
calls had been added.
runtime.assertI2T: nosplit stack overflow
120 assumed on entry to runtime.assertI2T
8 after runtime.assertI2T uses 112
0 on entry to runtime.newTypeAssertionError
-8 on entry to runtime.morestack01
runtime.assertE2E: nosplit stack overflow
120 assumed on entry to runtime.assertE2E
16 after runtime.assertE2E uses 104
8 on entry to runtime.panic
0 on entry to runtime.morestack16
-8 after runtime.morestack16 uses 8
runtime.assertE2T: nosplit stack overflow
120 assumed on entry to runtime.assertE2T
16 after runtime.assertE2T uses 104
8 on entry to runtime.panic
0 on entry to runtime.morestack16
-8 after runtime.morestack16 uses 8
runtime.newselect: nosplit stack overflow
120 assumed on entry to runtime.newselect
56 after runtime.newselect uses 64
48 on entry to runtime.printf
8 after runtime.printf uses 40
0 on entry to vprintf
-8 on entry to runtime.morestack16
runtime.selectdefault: nosplit stack overflow
120 assumed on entry to runtime.selectdefault
56 after runtime.selectdefault uses 64
48 on entry to runtime.printf
8 after runtime.printf uses 40
0 on entry to vprintf
-8 on entry to runtime.morestack16
runtime.selectgo: nosplit stack overflow
120 assumed on entry to runtime.selectgo
0 after runtime.selectgo uses 120
-8 on entry to runtime.gosched
On arm, 5c was tagging functions NOSPLIT that should
not have been, like the recursive function printpanics:
printpanics: nosplit stack overflow
124 assumed on entry to printpanics
112 after printpanics uses 12
108 on entry to printpanics
96 after printpanics uses 12
92 on entry to printpanics
80 after printpanics uses 12
76 on entry to printpanics
64 after printpanics uses 12
60 on entry to printpanics
48 after printpanics uses 12
44 on entry to printpanics
32 after printpanics uses 12
28 on entry to printpanics
16 after printpanics uses 12
12 on entry to printpanics
0 after printpanics uses 12
-4 on entry to printpanics
R=r, r2
CC=golang-dev
https://golang.org/cl/4188061
Program listed http://code.google.com/p/go/issues/detail?id=1495
(with nRequester set to 10000) will crash with
runtime: failed to create new OS thread (have 4526 already; errno=8)
instead of
runtime: failed to create new OS thread (have 618 already; errno=8).
R=golang-dev, rsc, vcc
CC=golang-dev
https://golang.org/cl/4172046
The object files begin with a header that is
$GOARCH
on a line by itself. This CL changes that header to
go object $GOOS $GOARCH release.2011-01-01 4567+
where the final two fields are the most recent release
tag and the current hg version number.
All objects imported into a Go compilation or linked into an
executable must have the same header line, and that header
line must match the compiler and linker versions.
The effect of this will be that if you update and run all.bash
and then try to link in objects compiled with an earlier version
of the compiler (or invoke the wrong version of the compiler),
you will get an error showing the different headers instead
of perhaps silent incompatibility.
Normal usage with all.bash should be unaffected, because
all.bash deletes all the object files in $GOROOT/pkg/$GOOS_$GOARCH
and cleans all intermediate object files before starting.
This change is intended to diagnose stale objects arising when
users maintaining alternate installation directories forget to
rebuild some of their files after updating.
It should help make the adoption of $GOPATH (CL 3780043)
less error-prone.
R=ken2, r
CC=golang-dev
https://golang.org/cl/4023063
- fixed length of amd64 .data pe section
(don't need to include non-initialised data)
- use correct oh/oh64 variable when updating
data directory in addexports
- simplify and cleanup
R=vcc, rsc
CC=golang-dev
https://golang.org/cl/4106044
* Avoid confusion between imported and exported symbols.
* Record number of imported and exported symbols correctly.
* Explictly relocate SMACHOSYM section, since it is not in datap.
R=rsc
CC=golang-dev
https://golang.org/cl/3920042
The recent linker changes broke NaCl support
a month ago, and there are no known users of it.
The NaCl code can always be recovered from the
repository history.
R=adg, r
CC=golang-dev
https://golang.org/cl/3671042
If an %lld argument can be 32 or 64 bits wide, cast to vlong.
If always 32 bits, drop the ll.
Fixes#1336.
R=brainman, rsc
CC=golang-dev
https://golang.org/cl/3580041
More support for references to dynamic symbols,
including full GOT and PLT for ELF objects.
For Mach-O everything ends up in the GOT: dealing
with the real lazy PLT is too hard for now so we punt.
R=iant, iant2
CC=golang-dev
https://golang.org/cl/3491042
8l was broken by commit 7ac0d2eed9, it caused .data to be page aligned in the file - which is not how Plan 9 expects things to be.
Also .rodata was layed out in a similar fashion.
Not sure when signame was introduced, but added a stub.
Removed the symo assignment in asm.c as it is not currently used.
Fix runtime breakage after commit 629c065d36 which prefixes all external symbols with runtime·.
R=rsc
CC=golang-dev
https://golang.org/cl/2674041
Restore ability to have different file and
section alignment in generated pe file.
Stop generating .bss pe section, it is
part of .data now.
Some code refactoring.
R=rsc, vcc
CC=golang-dev
https://golang.org/cl/2731041
Sub-symbols are laid out inside a larger symbol
but can be addressed directly.
Use to make Mach-O pointer array not a special case.
Will use later to describe ELF sections.
Glimpses of the beginning of ELF loading.
R=ken2
CC=golang-dev
https://golang.org/cl/2623043
Load the entire archive file instead.
Reduces I/O by avoiding additional passes
through libraries to resolve symbols.
Go packages always need all the files anyway
(most often, all 1 of them).
R=ken2
CC=golang-dev
https://golang.org/cl/2613042
Just enough to make mov instructions work,
which in turn is enough to make strconv work
when it avoids any floating point calculations.
That makes a bunch of other packages pass
their tests.
Should suffice until hardware floating point
is available.
Enable package tests that now pass
(some due to earlier fixes).
Looks like there is a new integer math bug
exposed in the fmt and json tests.
R=ken2
CC=golang-dev
https://golang.org/cl/2638041
That is, move the pc/ln table and the symbol table
into the read-only data segment. This eliminates
the need for a special load command to map the
symbol table into memory, which makes the
information available on systems that couldn't handle
the magic load to 0x99000000, like NaCl and ARM QEMU
and Linux without config_highmem=y. It also
eliminates an #ifdef and some clumsy code to
find the symbol table on Windows.
The bad news is that the binary appears to be bigger
than it used to be. This is not actually the case, though:
the same amount of data is being mapped into memory
as before, and the tables are still read-only, so they're
still shared across multiple instances of the binary as
they were before. The difference is just that the tables
aren't squirreled away in some section that "size" doesn't
know to look at.
This is a checkpoint.
It probably breaks Windows and breaks NaCl more
than it used to be broken, but those will be fixed.
The logic involving -s needs to be revisited too.
Fixes#871.
R=ken2
CC=golang-dev
https://golang.org/cl/2587041
Also change the span-dependent jump algorithm
to use fewer iterations:
* resolve forward jumps at their targets (comefrom list)
* mark jumps as small or big and only do small->big
* record whether a jump failed to be encodable
These changes mean that a function with only small
jumps can be laid out in a single iteration, and the
vast majority of functions take just two iterations.
I was seeing a maximum of 5 iterations before; the
max now is 3 and there are fewer that get even that far.
R=ken2
CC=golang-dev
https://golang.org/cl/2537041
Using explicit relocations internally, we can
represent the data for a particular symbol as
an initialized block of memory instead of a
linked list of ADATA instructions. The real
goal here is to be able to hand off some of the
relocations to the dynamic linker when interacting
with system libraries, but a pleasant side effect is
that the memory image is much more compact
than the ADATA list, so the linkers use less memory.
R=ken2
CC=golang-dev
https://golang.org/cl/2512041
The Plan 9 tools assume that long is 32 bits.
We converted all instances of long to int32 when
importing the code but missed the print formats.
Because int32 is always int on the compilers we use,
it is never correct to use %lux, %ld, etc. Convert to %ux, %d, etc.
(It matters because on 64-bit gcc, long is 64 bits,
so we were printing 32-bit quantities with 64-bit formats.)
R=ken2
CC=golang-dev
https://golang.org/cl/2491041
* Maintain Sym* list for text with individual
prog lists instead of using one huge list and
overloading p->pcond.
* Comment what each file is for.
* Move some output code from span.c to asm.c.
* Move profiling into prof.c, symbol table into symtab.c.
* Move mkfwd to ld/lib.c.
* Throw away dhog dynamic loading code.
* Throw away Alef become.
* Fix printing of WORD instructions in 5l -a.
Goal here is to be able to handle each piece of text or data
as a separate piece, both to make it easier to load the
occasional .o file and also to make it possible to split the
work across multiple threads.
R=ken2, r, ken3
CC=golang-dev
https://golang.org/cl/2335043
This is entirely adding and removing tabs.
It looks weird but will make the diffs for the
next change easier to read.
R=ken2
CC=golang-dev
https://golang.org/cl/2490041
6l was skipping emitting the (2 byte) symbol table if there were no imported or exported
symbols. You can't just drop the symbol table entirely - the linker dies if you have
a linkedit section but no table. You can omit the linkedit section or both the linkedit
and the dlyd parts in the right circumstances, but that seems much more risky to me.
R=rsc
CC=golang-dev
https://golang.org/cl/2421042
The Makefile and cgo now rewrite / to _ when creating the path.
The .so for gosqlite.googlecode.com/hg/sqlite is named
cgo_gosqlite.googlecode.com_hg_sqlite.so, and then 6l and 8l
both include a default rpath of $GOROOT/pkg/$GOOS_$GOARCH.
This should make it easier to move binaries from one system
to another.
Fixes#857.
R=iant, r
CC=golang-dev
https://golang.org/cl/1700048
eliminates spurious multiple initialization errors.
give more information in the multiple init errors that remain.
Fixes#87.
R=r
CC=golang-dev
https://golang.org/cl/194052
