Currently, ELF relocations are generated sequentially in the heap
and flushed to output file periodically. In fact, in some cases,
the output size of the relocation records can be easily computed,
as a relocation entry has fixed size. We only need to count the
number of relocation records to compute the size.
Once the size is computed, we can mmap the output with the proper
size, and directly write relocation records in the mapped memory.
It also opens the possibility of writing relocations in parallel
(not done in this CL).
Note: on some architectures, a Go relocation may turn into
multiple ELF relocations, which makes size calculation harder.
This CL does not handle those cases, and it still writes
sequentially in the heap there.
Linking cmd/compile with external linking,
name old time/op new time/op delta
Asmb2 190ms ± 2% 141ms ± 4% -25.74% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
Asmb2_GC 66.8MB ± 0% 8.2MB ± 0% -87.79% (p=0.008 n=5+5)
name old live-B new live-B delta
Asmb2_GC 66.9M ± 0% 55.2M ± 0% -17.58% (p=0.008 n=5+5)
Change-Id: If7056bbe909dc90033eef6b9c4891fcca310602c
Reviewed-on: https://go-review.googlesource.com/c/go/+/240399
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
When linking against a Go shared library, when a global variable
in the main module has a type defined in the shared library, the
linker needs to pull the GC data from the shared library to build
the GC program for the global variable. Currently, this fails
silently, as the shared library file is closed too early and the
read failed (with no error check), causing a zero GC map emitted
for the variable, which in turn causes the runtime to treat the
variable as pointerless.
For now, fix this by keeping the file open. In the future we may
want to use mmap to read from the shared library instead.
Also add error checking. And fix a (mostly harmless) mistake in
size caluculation.
Also remove an erroneous condition for ARM64. ARM64 used to have
a special case to get the addend from the relocation on the
gcdata field. That was removed, but the new code accidentally
returned 0 unconditionally. It's no longer necessary to have any
special case, since the addend is now applied directly to the
gcdata field on ARM64, like on all the other platforms.
Fixes#39927.
This is the second attempt of CL 240462. And this reverts
CL 240616.
Change-Id: I01c82422b9f67e872d833336885935bc509bc91b
Reviewed-on: https://go-review.googlesource.com/c/go/+/240621
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
The special symbols are linker-created symbols for special
purposes, therefore reachable (otherwise the linker won't create
them). Mark them so, so they get converted to sym.Symbols when we
convert to old symbol representation.
In particular, the failure for building shared library on PPC64
is due to .TOC. symbol not being converted to sym.Symbol, but
referenced in addmoduledata.
Change-Id: Iaf5d145ffa5d15122e86a6e6983514e56dd5d456
Reviewed-on: https://go-review.googlesource.com/c/go/+/240620
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This reverts CL 240462.
Reason for revert: test fails on PPC64LE.
Updates #39927.
Change-Id: I4f14fd0c36e604a80ae9f2f86d1e643e28945e93
Reviewed-on: https://go-review.googlesource.com/c/go/+/240616
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
When linking against a Go shared library, when a global variable
in the main module has a type defined in the shared library, the
linker needs to pull the GC data from the shared library to build
the GC program for the global variable. Currently, this fails
silently, as the shared library file is closed too early and the
read failed (with no error check), causing a zero GC map emitted
for the variable, which in turn causes the runtime to treat the
variable as pointerless.
For now, fix this by keeping the file open. In the future we may
want to use mmap to read from the shared library instead.
Also add error checking. And fix a (mostly harmless) mistake in
size caluculation.
Also remove an erroneous condition for ARM64. ARM64 used to have
a special case to get the addend from the relocation on the
gcdata field. That was removed, but the new code accidentally
returned 0 unconditionally. It's no longer necessary to have any
special case, since the addend is now applied directly to the
gcdata field on ARM64, like on all the other platforms.
Fixes#39927.
Change-Id: Iecd32315b326c7059587fdc190e2fa99426e497e
Reviewed-on: https://go-review.googlesource.com/c/go/+/240462
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Austin Clements <austin@google.com>
Currently, on most platforms, the start/end symbols runtime.text
and runtime.etext are defined in symtab pass and assigned values
in address pass. In some cases (darwin+dynlink or AIX+external),
however, they are defined and assigned values in textaddress pass
(because they need non-zero sizes). Then their values get
overwritten in address pass. This is bad. The linker expects
their values to be consistent. In particular, in CL 239281,
findfunctab is split to two parts. The two parts need to have a
consistent view of the start/end symbols. If its value changes in
between, bad things can happen.
This CL fixes it by always defining runtime.text/etext symbols in
the textaddress pass.
Fix darwin and AIX builds.
Change-Id: Ifdc1bcb69d99be1b7e5b4fd31d473650c03e3b9d
Reviewed-on: https://go-review.googlesource.com/c/go/+/240065
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
The loader's SymbolBuilder Add*/Set* methods include a call to mark
the underlying symbol as reachable (as a convenience, so that callers
would not have to set it explicitly). This code was carried over from
the corresponding sym.Symbol methods; back in the sym.Symbol world
unreachable symbols were never removed from the AllSyms slice, hence
setting and checking reachability was a good deal more important.
With the advent of the loader and the new deadcode implementation,
there is less of a need for this sort of fallback, and in addition the
implicit attr setting introduces data races in the the loader if there
are SymbolBuilder Add*/Set* method calls in parallel threads, as well
as adding overhead to the methods.
This patch gets rid of the implicit reachability setting, and instead
marks reachability in CreateSymForUpdate, as well as adding a few
explicit SetAttrReachable calls where needed.
Change-Id: I029a0c5a4a24237826a7831f9cbe5180d44cbc40
Reviewed-on: https://go-review.googlesource.com/c/go/+/237678
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Merge conflicts are mostly recently changed nm/objdump output
format and its tests. Resolved easily (mostly just using the
format on master branch).
Change-Id: I99d8410a9a02947ecf027d9cae5762861562baf5
Now the compiler-generated fingerprint is a hash of the export
data. We don't need to hash it ourselves in the linker. And the
linker doesn't need to read export data at all.
Fixes#33820.
Change-Id: I54bf3ebfd0f0c72aa43a352d7b2e0575dd62970d
Reviewed-on: https://go-review.googlesource.com/c/go/+/236119
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Safe mode in the compiler is removed in CL 142717 in Go 1.12. I
think we can delete safe mode from the linker as well.
Change-Id: I201e84fca3a566a1bb84434ab4d504516160ac4e
Reviewed-on: https://go-review.googlesource.com/c/go/+/236117
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Move lots of the binary-file format specific pieces into their
appropriate places. Similarly rescope some variables to just ld.
Change-Id: I74bc6d8aba58f5ac86e6579be1fcb356c4636825
Reviewed-on: https://go-review.googlesource.com/c/go/+/235278
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Set linker explicitly to lld because the default does not work on NDK
versions r19c, r20, r20b and r21. NDK 18b (or earlier) based builds
will need to specify -fuse-ld=gold.
Fixes#38838
Change-Id: Ib75f71fb9896b843910f41bd12aa1e36868fa9b3
GitHub-Last-Rev: eeaa171604
GitHub-Pull-Request: golang/go#39217
Reviewed-on: https://go-review.googlesource.com/c/go/+/235017
Reviewed-by: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Elias Naur <mail@eliasnaur.com>
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CL 235017 is about to change the default Android linker to lld. lld doesn't
support the --compress-debug-sections=zlib-gnu flag, but linkerFlagSupported
doesn't take any alternative linkers specified with -fuse-ld into account.
Updates #38838
Change-Id: I5f7422c06d40dedde2e4b070fc48398e8f822190
Reviewed-on: https://go-review.googlesource.com/c/go/+/235157
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Now the only thing it does is to track versions. Move it to ctxt.
And delete sym.Symbols.
Change-Id: Ie6b974f9bf79c4f33ace02213dcb89463eadd26a
Reviewed-on: https://go-review.googlesource.com/c/go/+/234884
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Lots of the architecture specific code for asmb() is very simimar. As
such, move to a common function.
Change-Id: Id1fd50ee7bfa1bc9978e3f42ad08914b04cd677b
Reviewed-on: https://go-review.googlesource.com/c/go/+/234683
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This deletes all sym.Symbol and sym.Reloc references. This is
certainly not complete, and there are more cleanups to do. But I
feel this makes a good first round.
Change-Id: I7621d016957f7ef114be5f0606fcb3ad6aee71c8
Reviewed-on: https://go-review.googlesource.com/c/go/+/234097
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Minor renaming cleanup to get rid of a couple of old sym.Symbol
adddynrel helpers and rename the current crop of adddynrel2
methods/functions back to adddynrel.
Change-Id: I67e76decff84d603ef765f3b6a0cd78c7f3743ec
Reviewed-on: https://go-review.googlesource.com/c/go/+/233523
Run-TryBot: Than McIntosh <thanm@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
Adds in support for remaining architectures to the linker's ELF asmb2
path, along with deleting most of the older sym.Symbol based code.
Change-Id: I67c96525db72b7d6dd3187cf2b9f6faddc296291
Reviewed-on: https://go-review.googlesource.com/c/go/+/233362
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This patch converts the linker's Asmb2 phase to use loader APIs
for AMD64 (other architectures to be converted in a subsequent
patch).
Change-Id: I5a9aa9b03769cabc1a22b982f48fd113213d7bcf
Reviewed-on: https://go-review.googlesource.com/c/go/+/233338
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
We use the new one everywhere now.
Change-Id: Ic9b1314e71e4666500cbf1689bb93839e040682a
Reviewed-on: https://go-review.googlesource.com/c/go/+/232982
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Now we no longer do loadlibfull on windows.
Change-Id: Ideb015597c28f27538bd50829e089ea728017162
Reviewed-on: https://go-review.googlesource.com/c/go/+/232979
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Now we no longer do loadlibfull on darwin.
While here, remove residual darwin/386 and darwin/arm code.
Change-Id: I6efdcd81baeeca29d1fe91c4fab0cc8241a58e2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/232597
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
The undef pass basically double-checks the relocation targets are
defined. We already do that in the reloc pass, and for external
relocations we check that when we emit relocations. The undef pass
doesn't seem necessary.
Change-Id: Iecfa654dc014fdc6e59c624cbf5948ad65fd367a
Reviewed-on: https://go-review.googlesource.com/c/go/+/232577
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Convert the part that uses relocations to use loader.ExtReloc
directly. It still uses sym.Symbols for now, but not sym.Relocs.
This reduces some memory usage: linking cmd/compile with external
linking,
name old allocs/op new allocs/op delta
Loadlibfull_GC 52.2MB ± 0% 13.9MB ± 0% -73.40% (p=0.008 n=5+5)
name old live-B new live-B delta
Loadlibfull_GC 75.5M ± 0% 61.9M ± 0% -18.02% (p=0.008 n=5+5)
Change-Id: I317ecbf516063c42b255b2caba310ea6281342d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/231319
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Adddynrel2 is a function pointer. In dynrelocsym we pass &r to
it, which will cause r to escape. Pass it by value instead.
Linking cmd/compile,
name old alloc/op new alloc/op delta
Dodata_GC 15.8MB ± 0% 5.9MB ± 0% -62.55% (p=0.008 n=5+5)
Change-Id: Ib86005d1026ebaca57777b27ead037e613585f44
Reviewed-on: https://go-review.googlesource.com/c/go/+/231045
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Archreloc2 is a function pointer. It will escape its pointer
arguments. In relocsym, as we pass &r and &rr to Archreloc2, it
causes them to escape, even if Archreloc2 is not actually called.
Instead, pass r by value. loader.Reloc2 is a small structure
which is intended to be passed by value.
For rr, as Archreloc2 will likely return true, we speculatively
add it to extRelocs slice and use that space to pass to
Archreloc2.
Linking cmd/compile,
name old alloc/op new alloc/op delta
Dwarfcompress_GC 110MB ± 0% 24MB ± 0% -78.34% (p=0.008 n=5+5)
Reloc_GC 24.6MB ± 0% 0.0MB ± 0% -100.00% (p=0.029 n=4+4)
Linking cmd/compile using external linking
name old alloc/op new alloc/op delta
Reloc_GC 152MB ± 0% 36MB ± 0% -76.07% (p=0.008 n=5+5)
Change-Id: I1415479e0c17ea9787f9a62453dce00ad9ea792f
Reviewed-on: https://go-review.googlesource.com/c/go/+/231077
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Non functional, but required by the majority of the architectures.
Change-Id: I57601016c28ce665a9d434e283a1db8bded9b133
Reviewed-on: https://go-review.googlesource.com/c/go/+/230858
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Remove 'Sub' field from sym.Symbol, replacing uses (those downstream of
loadlibfull) with loader method calls.
NB: removing the Outer field will have to wait for now; it is accessed
in archreloc methods that don't have access to link ctxt or loader
currently.
Change-Id: I2abe5906fc169c64b2ab7d5ad213619bea5a17c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/230617
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Only enabled for AMD64 when internal linking for now.
Change-Id: I2aa9ee47c0f7413ea7bbcdd31b8317c14220bba3
Reviewed-on: https://go-review.googlesource.com/c/go/+/230302
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Remove the "ElfSym" and "LocalElfSym" fields from sym.Symbol,
replacing uses with loader method calls as needed.
Change-Id: I3828f13203ece2bdc03eeb09ab37a5c94e21a726
Reviewed-on: https://go-review.googlesource.com/c/go/+/230462
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Remove the 'Gotype' field from sym.Symbol, as it is now no longer
used. Store the loader.Sym for a symbol as a field in sym.Symbol
("SymIdx"). Then remove sym.Symbol 'File' field, and replace the field
accesses in question with calls into the loader instead.
Change-Id: I01c5504425006b8d3fe77fac2b69a86e198c7a5a
Reviewed-on: https://go-review.googlesource.com/c/go/+/230304
Run-TryBot: Than McIntosh <thanm@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
None of the users of genasmsym are doing anything with the Gotype
field of sym.Symbol, so remove that param from the callback function.
Change-Id: Ie902c4cdbcc6b68d353daf5ce21a99012161a946
Reviewed-on: https://go-review.googlesource.com/c/go/+/230545
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Make Wasm more like other architectures, writing data sections to
heap in Asmb instead of Asmb2. Then we can remove the
copy-on-write logic in applying relocations.
Change-Id: I26d5315ea9fba032fe4bdb9b5c7fe483611c4373
Reviewed-on: https://go-review.googlesource.com/c/go/+/230465
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This reverts CL 229994.
Reason for revert: break AIX build.
This is nice to have but isn't critical. We can revisit later.
Change-Id: Ifc56a0a4c0fb36859cf7666ab149e25e0e5d4cc0
Reviewed-on: https://go-review.googlesource.com/c/go/+/230459
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
symGroupType was needed for dodata. Now that we have converted
dodata to using the loader, stop overwriting it.
Change-Id: Ie94109c0b35dd2f71a19ebb38f8cf20b6a37c624
Reviewed-on: https://go-review.googlesource.com/c/go/+/229994
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>
Previous CL introduced index fingerprint in the object files.
This CL implements the second part: checking fingerprint
consistency in the linker when packages are loaded.
Change-Id: I05dd4c4045a65adfd95e77b625d6c75a7a70e4f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/229618
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This patch begins the work of converting the linker's dodata phase to
work with loader APIs. Passes all.bash on linux/amd64, but hasn't been
tested on anything else (more arch-specific code needs to be written).
Use of the new dodata() phase is currently gated by a temporary
command line flag ("-newdodata"), and there is code in the linker's
main routine to insure that we only use the new version for the right
GOOS/GOARCH (currently restricted to ELF + AMD64).
Change-Id: Ied3966677d2a450bc3e0990e0f519b3fceaab806
Reviewed-on: https://go-review.googlesource.com/c/go/+/229706
Run-TryBot: Than McIntosh <thanm@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
Move the guts of ctxt.Errorf into loader.Loader, so that we can make
calls to it from functions that have a "*loader.Loader" available but
not a "ctxt *Link". This is needed to start converting hooks like
"adddynrel" in the arch-specific portions of the linker to use loader
APIs.
Change-Id: Ieedd4583b66504be0e77d7f3fbadafe0d2307a69
Reviewed-on: https://go-review.googlesource.com/c/go/+/229497
Run-TryBot: Than McIntosh <thanm@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Change the timing for preprocessing of integer/floating point constant
symbols so that we populate them with content at an earlier stage.
This is needed to allow them can be picked up by the loader-API
version of dodata().
Change-Id: Icf09f4f4b318b4f77e11d4a0f0a9cbecd76a1d6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/229438
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
It is no longer needed as we have converted the fieldtrack pass
to using the loader.
Also free loader.Reachparent after we are done with it.
Change-Id: Ibc4b29f282e1e4aea363a1b549755e31f84b0295
Reviewed-on: https://go-review.googlesource.com/c/go/+/229322
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Jeremy Faller <jeremy@golang.org>
Currently, we use a dense array to store symbol's sections. The
array element is a *sym.Section, which takes 8 bytes per symbol
on a 64-bit machine. And the array is created upfront.
To reduce memory usage, use a 16-bit index for sections, so we
store 2 bytes per symbol. The array is pointerless, reducing GC
work. Also create the array lazily.
This reduces some memory usage: linking cmd/compile,
name old alloc/op new alloc/op delta
Loadlib_GC 42.1MB ± 0% 36.2MB ± 0% -14.01% (p=0.008 n=5+5)
name old live-B new live-B delta
Loadlib_GC 16.8M ± 0% 15.4M ± 0% -8.36% (p=0.008 n=5+5)
Archive_GC 98.2M ± 0% 97.2M ± 0% -1.02% (p=0.008 n=5+5) # at the end
Change-Id: If8c41eded8859660bca648c5e6fdf5830810fbf6
Reviewed-on: https://go-review.googlesource.com/c/go/+/229306
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This is more or less a direct translation, to get things going.
There are more things we can do to make it better, especially on
the handling of container symbols.
Change-Id: I11a0087e402be8d42b9d06869385ead531755272
Reviewed-on: https://go-review.googlesource.com/c/go/+/229125
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Change linker DWARF generation to move away from emitting a single
giant list of DWARF symbols, and instead emit a list of descriptors,
with each descriptor holding the symbols for a specific DWARF section.
While placing all DWARF symbols in a single lists does come in handy
in certain instances, it also creates a lot of confusion and weird
code in other cases, specifically where we want to perform operations
on a section-by-section basis (resulting in code that tries to
re-discover section boundaries by walking/inspecting the list).
Change-Id: I4dac81bd38cba903c9fd7004d613597e76dfb77a
Reviewed-on: https://go-review.googlesource.com/c/go/+/228780
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
deadcode's been completely replaced. Make its death official.
Change-Id: I85f1e3968463f216b8bce2fb7217c3b51641939f
Reviewed-on: https://go-review.googlesource.com/c/go/+/229002
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Hoist dwarfGenerateDebugSyms call up out of dodata to before
loadlibfull. This required a couple of small tweaks to the
loader and to loadlibfull.
Change-Id: I48ffb450d2e48b9e55775b73a6debcd27dbb7b9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/228221
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
It is no longer used. The only remaining use is in generating
Plan 9 debug info, which is already not supported.
Change-Id: Ia023d6f2fa7d57b97ba861ce464e2eec8ac2d1f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/228142
Reviewed-by: Than McIntosh <thanm@google.com>
Rework the linker's pcln phase to work with the new loader. As part of
this set of changes the handling of "go.file..." symbols has been
revised somewhat -- previously they were treated as always live in the
loader, and now we no longer do this.
The original plan had been to have the new implementation generate
nameless "inltree" symbols, however the plan now is to keep them
named for now and convert them to nameless in a subsequent patch.
Change-Id: If71c93ff1f146dbb63b6ee2546308acdc94b643c
Reviewed-on: https://go-review.googlesource.com/c/go/+/227759
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This removes all conditions and conditional code (that I could find)
that depended on darwin/386.
Fixes#37610.
Change-Id: I630d9ea13613fb7c0bcdb981e8367facff250ba0
Reviewed-on: https://go-review.googlesource.com/c/go/+/227582
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Implement text address assignment and trampoline generation using
the loader.
Note: the trampoline insertion part doesn't actually work. It
also needs to propagate Aux symbols for external symbols in
LoadFull. But it won't be needed after converting pclntab
generation, so I'll leave it out for now. This could break
linking large binaries on PPC64 and ARM.
Change-Id: Ie46a35b25d7c027983dd877207cfa8f67c32530b
Reviewed-on: https://go-review.googlesource.com/c/go/+/227482
Reviewed-by: Than McIntosh <thanm@google.com>
SymFile, derived from sym.Symbol.File, is supposed to return the
package path, instead of the file name (arguably the name is
confusing). Make it so, and rename it to SymPkg.
Change-Id: I67bcd12f67cea271f2a2ce3c5724e5d228f5b2f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/227481
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
The code in setArchsyms that sets up TOC symbols was buggy; it was
kicking in only for aix-ppc64 and not linux-ppc64. These symbols are
required for both ABIs, so change the guard in question from
"ctx.IsAIX()" to "ctxt.IsPPC64()". Also, the code to create versioned
".TOC." syms was not passing the correct symbol version to the loader
(now fixed).
Change-Id: I356071e528beadad20f61d067059eaf26f06e06b
Reviewed-on: https://go-review.googlesource.com/c/go/+/227257
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Begin the job of converting the linker's "gentext" phase over to use
loader APIs. This patch includes most architectures except for s390x
and PPC (these will be added in subsequent patches, since they require
a couple of loader changes first).
Change-Id: Ic7f55c207dcdbbba657330ef007a72ff7c837416
Reviewed-on: https://go-review.googlesource.com/c/go/+/227017
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
In stack bound check pass, check a call once, not over and over
again. Fix an accidental quadratic behavior...
In particular, switching to the new linker caused MIPS builders
noticeably slower. This CL fixes it.
Change-Id: Idd00c79e80af6278652c92a1d9d7bb2d194e9490
Reviewed-on: https://go-review.googlesource.com/c/go/+/227078
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Austin Clements <austin@google.com>
The Count field in Relocs type is always equal to len(rs). Unify
them.
Change-Id: Ic77288ea58b61a98482b218e051d81047d0ddd88
Reviewed-on: https://go-review.googlesource.com/c/go/+/226717
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Introduces a parallel OutBuf implementation, and POC on amd64. Due to
some of the weird behaviors I saw on MacOS (SIGBUS while calling msync),
I will wait for feedback to port to other architectures.
On my mac, sped up Asmb by ~78% for cmd/compile (below). Will likely
have an appreciable speedup on kubelet benchmark.
Asmb 39.1ms ±11% 8.5ms ±10% -78.17% (p=0.000 n=10+9)
TotalTime 596ms ± 2% 577ms ± 8% -3.07% (p=0.034 n=8+10)
Change-Id: Id2a2577c3f4da155d8dccc862897f43b941877ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/223742
Run-TryBot: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Add some new loader.Sym equivalents to the archSyms struct so that we
can run setArchSyms earlier in the pipeline, and add a "mode" to
setArchSyms to control whether it should create loader.Sym symbols or
their *sym.Symbol equivalents.
These change needed for a subsequent patch in which addexport() is run
earlier as well
Change-Id: I0475c9388c39f13e045dd4aa9c90eaec42624810
Reviewed-on: https://go-review.googlesource.com/c/go/+/226361
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This should restore deterministic order of dynexp, and fix
Solaris build.
Change-Id: Icb796babaa3238bff90fd8255ee9f023f2306c26
Reviewed-on: https://go-review.googlesource.com/c/go/+/225538
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
It is needed in Xcoffadddynrel. And it will be needed once we
move more things to new style (the sym.Symbol parameters will
also need to change).
Change-Id: Ie12683f9b44e21f1e6ea711bf2f4c5c32282e5b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/225203
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Populate ArchSyms with loader.Sym versions of important symbols,
so as to be able to convert the code that uses ArchSyms to the
new loader interfaces.
Change-Id: If6766f7164642a9dc2e31fcf7f9280a6e95e5d23
Reviewed-on: https://go-review.googlesource.com/c/go/+/224383
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Rewrite setupdynexp to work with loader.Sym, and move the call to it
before the body of loadlibfull. After loadlibfull is complete,
construct the old *sym.Symbol version of dynexp, since not all all
clients that access this list are converted to the loader APIs.
Change-Id: I347d24958e2f3e2332fbe33f2eb6ec25cc126bdb
Reviewed-on: https://go-review.googlesource.com/c/go/+/224382
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Add an Errorf method to ErrorReporter. The hope is that we can
consolidate error handling/reporting in this helper, and eventually
do away with Link.Errorf and the global Errorf function (which
can be removed once we've eliminated enough uses of *sym.Symbol).
Change-Id: Ie1147020b8409b9c57acfd71c942b287b214afca
Reviewed-on: https://go-review.googlesource.com/c/go/+/224380
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Use symbol's Extname, instead of symbol renaming, for the mangled
names.
The old symbol Rename has an interesting logic of "merging"
symbols, when a symbol is renamed to the name of an existing
symbol. It turns out that this is needed for linking against
shared libraries, where the Go object has a reference to a symbol
with the original name, and the shared libary provides a symbol
under the mangled name. Implement this logic with the loader.
Change-Id: Ib95d7a9c93a52f8e02f4a51ac67240d6ebfc1c6a
Reviewed-on: https://go-review.googlesource.com/c/go/+/224939
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This change moves datap from global space into the link context. Rather
than having it exist in context, we could have it returned from dodata,
and pass it as a parameter, but it is used in awkward places in the
Arch functions. Easiest for now is just keeping it in the context, until
we more formally move it to slices of loader.Sym.
This is a largely non-functional change.
Change-Id: Ica93bd857c39913ad470a61c63bc8d21704d6308
Reviewed-on: https://go-review.googlesource.com/c/go/+/222664
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This is a non-functional change, just moving things around, making
dodata a more approachable piece of code.
Change-Id: I06fa047cbef2313040a31998fa8d242ccb2fedea
Reviewed-on: https://go-review.googlesource.com/c/go/+/222662
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
I thought that only non-static symbols need TOC, but apparently
this is not true. We need to use versioned .TOC. symbols.
Partially fix AIX build. There is still another problem, but this
gets us a bit farther in make.bash.
Change-Id: I40ba4a4dd27da0fc6ab26e4a54ff76bd2930aef1
Reviewed-on: https://go-review.googlesource.com/c/go/+/223379
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Use a different mechanism to access relocations from the object
files, and use it in the stack bounds check pass. This shows some
speedup.
(linking cmd/compile)
Dostkcheck 76.9ms ± 1% 55.1ms ± 1% -28.36% (p=0.008 n=5+5)
Change-Id: I2ac42da515dccd64719fb557ffff6cdc69e4319b
Reviewed-on: https://go-review.googlesource.com/c/go/+/222240
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Remove the temporary "-newdw2" linker command line option, along with
the remainder of the legacy sym.Symbol based DWARF generation code.
Change-Id: I86c0581dd021cd4e2209ca9bc45f34037d42323c
Reviewed-on: https://go-review.googlesource.com/c/go/+/222766
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
dodata is a pile of dependencies on *Link. Pull some of these
dependencies out, and tighten up the visibility on the functions.
Change-Id: Id213f19ae7b63dd246ddb47b77ffde99f615aa80
Reviewed-on: https://go-review.googlesource.com/c/go/+/222061
Reviewed-by: Than McIntosh <thanm@google.com>
Implement a TODO in CL 220059, now that CL 220985 is in.
Change-Id: I7273a7b9e1e7c0b916780571c9c954da21366429
Reviewed-on: https://go-review.googlesource.com/c/go/+/222239
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Change the loader method AssignTextSymbolOrder to return a slice of
all reachable textp symbols, since it will be needed in second-phase
DWARF gen.
Change-Id: Iaf16ee9cf0d5266aeb0d3df596e8117263b35d8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/220985
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This is the last step requried before relocsym can go parallel.
Change-Id: Id1c1c530c2b9277917208c3767eeb29e02c17a9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/220841
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Also correct a few places I hadn't switched over to Target from *Link
context.
Change-Id: I6de6b39723762de3fa5f8d12800085421aca76fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/220840
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This CL converts the stack bound check pass to use the loader and
new symbol representation.
Change-Id: I0e4c102909db20dc2d5a367379146728862e53cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/220059
Reviewed-by: Than McIntosh <thanm@google.com>
We need to propogate Target through the relocation functions.
Change-Id: I1192d54a20a34569fd13c1511d2b21ebf2d1272e
Reviewed-on: https://go-review.googlesource.com/c/go/+/220839
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Remove the "-newdw" command line option, a temporary placeholder/gate
for the first phase of new DWARF gen, along with some portions of the
sym.Symbol based DWARF type gen code. The remainder of the old code
will be removed in a subsequent patch.
Change-Id: I7870539f020fbf05d0345d3af2acf383fae94892
Reviewed-on: https://go-review.googlesource.com/c/go/+/220984
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
This CL implements windows version of -buildmode=pie code in both
cmd/go and cmd/link.
Windows executables built with -buildmode=pie set (unlike the one
built with -buildmode=exe) will have extra .reloc PE section, and
will have no IMAGE_FILE_RELOCS_STRIPPED flag set. They will also
have IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE flag set, and
IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA flag set for windows/amd64.
Both cgo and non-cgo versions are implemented. And TestBuildmodePIE
is extended to test both cgo and non-cgo versions on windows and
linux.
This CL used some code from CLs 152759 and 203602.
RELNOTE=yes
Fixes#27144
Updates #35192
Change-Id: I1249e4ffbd79bd4277efefb56db321c390c0f76f
Reviewed-on: https://go-review.googlesource.com/c/go/+/214397
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The bootstrapping process (make.bash) on all other platforms use
internal linking. This change brings android/arm64 in line, fixing the
scary warning on our self-hosted Corellium builders:
warning: unable to find runtime/cgo.a
The linkmode default is changed to internal for all Android programs,
but in practice that won't matter outside our builders: using Go with
Android apps requires buildmode=c-shared which uses linkmode external.
Fixes#31343
Updates #31819
Change-Id: I3b3ada5ed69a7989e6d8e5960bbebf5e1c22aada
Reviewed-on: https://go-review.googlesource.com/c/go/+/207299
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Cherry Zhang
Than McIntosh
Tobias Klauser
Jeremy Faller
Paul D. Weber
Elias Naur
Austin Clements
Alex Brainman