This CL gives Linkmode a type, switches it to the standard flag
handling mechanism, and deduplicates some logic.
There is a semantic change in this CL. Previously if a link was
invoked explicitly with -linkmode=internal, any condition that forced
external linking would silently override this and use external
linking. Instead it now fails with a reason why. I believe this is an
improvement, but will change it back if there's disagreement.
Fixes#12848
Change-Id: Ic80e341fff65ecfdd2b6fdd6079674cc7210fc5f
Reviewed-on: https://go-review.googlesource.com/28971
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL contains several linker changes to support creating plugins.
It collects the exported plugin symbols provided by the compiler and
includes them in the moduledata.
It treats a binary as being dynamically linked if it imports the plugin
package. This lets the dynamic linker de-duplicate symbols.
Change-Id: I099b6f38dda26306eba5c41dbe7862f5a5918d95
Reviewed-on: https://go-review.googlesource.com/27820
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
According to golang.org/s/go12symtab, for N files, it should put N+1
there.
Fixes#17132.
Change-Id: I0c84136855c6436be72b9d3c407bf10d4c81a099
Reviewed-on: https://go-review.googlesource.com/29275
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This gets -buildmode=pie -ldflags=-linkmode=internal working on
Ubuntu 16.04.
Fixes#17068
Change-Id: Ice5036199005fb528cc58279a7f057170dc6b73d
Reviewed-on: https://go-review.googlesource.com/29118
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: I11899096c71ee0e24e902c87914601fcd7ffd7a9
Reviewed-on: https://go-review.googlesource.com/28967
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
main.main and main.init were not being marked as reachable.
Fixes#17076
Change-Id: Ib3e29bd35ba6252962e6ba89173ca321ed6849b9
Reviewed-on: https://go-review.googlesource.com/28996
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Part of adding PIE internal linking on linux/amd64.
Change-Id: I5ce01d1974e5d4b1a8cbcc8b08157477631d8d24
Reviewed-on: https://go-review.googlesource.com/28543
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Part of adding PIE internal linking on linux/amd64.
Change-Id: I586e7c2afba349281168df5e20d2fdcb697f6e37
Reviewed-on: https://go-review.googlesource.com/28542
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Details: http://www.airs.com/blog/archives/189
Part of adding PIE internal linking on linux/amd64.
Change-Id: I8843a97f22f6f120346cccd694c7fff32f09f60b
Reviewed-on: https://go-review.googlesource.com/28541
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When cmd/compile generates position-independent code on linux
(the -shared flag), it refers to runtime.tlsg as a TLS IE variable.
When cmd/link is linking a PIE executable internally, all TLS IE
relocations are generated by cmd/compile, and the variable they
refer to, runtime.tlsg, is local to the binary. This means we can
optimize this particular IE case to LE, and thus implement IE
support when internally linking.
To do this optimization in the linker, we need to rewrite the
PC-relative MOVD to a constant load. This may seem like an
unconscionable act born of enthusiasm, but it turns out this is
standard operating procedure for linkers. GNU gold does exactly
the same optimization. I spent some time reading it and documented
at least one missing feature from this version.
Part of adding PIE internal linking on linux/amd64.
Change-Id: I1eb068d0ec774724944c6b308aa5084582ecde0b
Reviewed-on: https://go-review.googlesource.com/28540
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This reuses the machinery built for dynamic loading of shared
libraries. The significant difference with PIE is we generate
dynamic relocations for known internal symbols, not just
dynamic external symbols.
Part of adding PIE internal linking on linux/amd64.
Change-Id: I4afa24070bfb61f94f8d3648f2433d5343bac3fe
Reviewed-on: https://go-review.googlesource.com/28539
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When internally linking with using rel.ro sections, this segment covers
the sections. To do this, move to other read-only sections, SELFROSECT
and SMACHOPLT, out of the way.
Part of adding PIE internal linking on linux/amd64.
Change-Id: I4fb3d180e92f7e801789ab89864010faf5a2cb6d
Reviewed-on: https://go-review.googlesource.com/28538
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Moves the grouping of symbol kinds (sections) into cmd/internal/obj
to keep it near the definition. Groundwork for CL 28538.
Change-Id: I99112981e69b028f366e1333f31cd7defd4ff82c
Reviewed-on: https://go-review.googlesource.com/28691
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
As cmd/internal/obj is coordinating the definition of GOOS, GOARCH,
etc across the compiler and linker, turn its functions into globals
and use them everywhere.
Change-Id: I5db5addda3c6b6435c37fd5581c7c3d9a561f492
Reviewed-on: https://go-review.googlesource.com/28854
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Separate out windows/windowsgui properly so we are not encoding some
of the Headtype value in a separate headstring global.
Remove one of the two copies of the variable from cmd/link.
Remove duplicate string to headtype list.
Change-Id: Ifa20fb9652a1dc95161e154aac11f15ad0f709d0
Reviewed-on: https://go-review.googlesource.com/28853
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The -shared flag has been superseded by the -buildmode flag.
Change-Id: I3682cc0367b919084c280d7dc64746485c1d4ddd
Reviewed-on: https://go-review.googlesource.com/28852
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
This program is written in Go now.
Change-Id: Ieec21a1bcac7c7a59e88cd1e1359977659de1757
Reviewed-on: https://go-review.googlesource.com/28549
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
cmd/go links mingwex and mingw32 libraries to every package it builds.
This breaks when 2 different packages call same gcc standard library
function pow. gcc linker appends pow implementation to the compiled
package, and names that function "pow". But when these 2 compiled
packages are linked together into the final executable, linker
complains, because it finds two "pow" functions with the same name.
This CL stops linking of mingwex and mingw32 during package build -
that leaves pow function reference unresolved. pow reference gets
resolved as final executable is built, by having both internal and
external linker use mingwex and mingw32 libraries.
Fixes#8756
Change-Id: I50ddc79529ea5463c67118d668488345ecf069bc
Reviewed-on: https://go-review.googlesource.com/26670
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Fixes#16911.
Fix obsolete inferno-os links, since code.google.com shutdown.
This CL points to the right files by replacing
http://code.google.com/p/inferno-os/source/browse
with
https://bitbucket.org/inferno-os/inferno-os/src/default
To implement the change I wrote and ran this script in the root:
$ grep -Rn 'http://code.google.com/p/inferno-os/source/browse' * \
| cut -d":" -f1 | while read F;do perl -pi -e \
's/http:\/\/code.google.com\/p\/inferno-os\/source\/browse/https:\/\/bitbucket.org\/inferno-os\/inferno-os\/src\/default/g'
$F;done
I excluded any cmd/vendor changes from the commit.
Change-Id: Iaaf828ac8f6fc949019fd01832989d00b29b6749
Reviewed-on: https://go-review.googlesource.com/27994
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This will allow it to depend on whether plugin.Open is a symbol to be
linked in.
Change-Id: Ie9aa4216f2510fe8b10bc4665c8b19622b7122ea
Reviewed-on: https://go-review.googlesource.com/27819
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
As far as I can tell, this check has been
non-functional since it was introduced.
This cuts 57k off cmd/go and 70k off cmd/compile.
Based on golang.org/cl/24710 by Josh Bleecher Snyder.
Change-Id: I1162a066971df1a067b50afa1cfa0819a6913574
Reviewed-on: https://go-review.googlesource.com/27830
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Replace the various calls to Fprintf(ctxt.Bso, ...) with a helper,
ctxt.Logf. This also addresses the various inconsistent flushing of
ctxt.Bso.
Because we have two Link structures, add Link.Logf in both places.
Change-Id: I23093f9b9b3bf33089a0ffd7f815f92dcd1a1fa1
Reviewed-on: https://go-review.googlesource.com/27730
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This change moves the ld.Cpos function to a method on coutbuf. This is
part of a larger change that makes ld.outbuf look more like a bio.Buf in
an effort to eventually replace the former with the latter.
Change-Id: I506f7131935a2aa903fa302a0fab0c5be50220fd
Reviewed-on: https://go-review.googlesource.com/27578
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
In many places where ctx.Bso.Flush is used as the target for some debug
logging, ctx.Bso.Flush is called unconditionally. In the majority of
cases where debug logging is not enabled, this means Flush is called
many times when there is nothing to be flushed (it will be called anyway
when ctx.Bso is eventually closed), sometimes in a loop.
Avoid this by moving the ctx.Bso.Flush call into the same condition
block as the debug print. This pattern was previously applied
sporadically.
Change-Id: I0444cb235cc8b9bac51a59b2e44e59872db2be06
Reviewed-on: https://go-review.googlesource.com/27579
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Update goobj reader so it can provide all the information
necessary to disassemble .o (and .a) files.
Grab architecture of .o files from header.
.o files have relocations in them. This CL also contains a simple
mechanism to disassemble relocations and add relocation info as an extra
column in the output.
Fixes#13862
Change-Id: I608fd253ff1522ea47f18be650b38d528dae9054
Reviewed-on: https://go-review.googlesource.com/24818
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
I've also unexported a few symbols that weren't used outside the
package.
Updates #16818
Change-Id: I39d9d87b3eec30b88b4a17c1333cfbbfa6b3518f
Reviewed-on: https://go-review.googlesource.com/27468
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This permits people to use -buildmode=c-archive to produce an archive
file that can be included in a PIE or shared library.
Change-Id: Ie340ee2f08bcff4f6fd1415f7d96d51ee3a7c9a1
Reviewed-on: https://go-review.googlesource.com/24180
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Keep flagInterpreter unchanged after flag parsing. This lets us replace
flagInterpreterSet with flagInterpreter != "".
Change-Id: Ifd2edbb2ce0011e97276ca18281b8ffbabde1c50
Reviewed-on: https://go-review.googlesource.com/27563
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
CL 27473 accidentally changed `!Debug['I']` to `*flagInterpreter != ""`.
Since the old `Debug['I']` was set when the new *flagInterpreter was
set, this inverted the sense of the condition. The effect was to always
ignore the cgo_dynamic_interpreter setting from runtime/cgo. This worked
OK when the default interpreter was the correct one, but failed when it
was not, as is currently the case on, at least, PPC64 and ARM.
This CL restores the old behavior by using a separate variable to track
whether the -I flag was used, just as we used to.
Change-Id: Icf9b65fa41349ed2e4de477fec0a557ef1eb8189
Reviewed-on: https://go-review.googlesource.com/27562
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
My flags change reversed the meaning of -s within mips64's
linker code. This should fix that.
Change-Id: Ia24002469e557fb29badfd830134e61c1dd7e16e
Reviewed-on: https://go-review.googlesource.com/27555
Reviewed-by: Minux Ma <minux@golang.org>
This moves many of the flag globals into main and assigns them
to their flag.String/Int64/... directly.
Updates #16818
Change-Id: Ibbff44a273bbc5cb7228e43f147900ee8848517f
Reviewed-on: https://go-review.googlesource.com/27473
Reviewed-by: David Crawshaw <crawshaw@golang.org>
It's always called with the same arguments now.
Maybe the real fix is to make Symbol.Sub a slice but that requires a bit more
brain.
Change-Id: I1326d34a0a327554be6d54f9bd402ea328224766
Reviewed-on: https://go-review.googlesource.com/27416
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
The obj library's flag functions are (mostly) light wrappers
around the standard library flag package. Use the flag package
directly where possible.
Most uses of the 'count'-type flags (except for -v) only check
against 0, so they can safely be replaced by bools. Only -v
and the flagfns haven't been replaced.
Debug has been turned into a slice of bools rather than ints.
There was a copy of the -v verbosity in ctxt.Debugvlog, so don't use
Debug['v'] and just use ctxt.Debugvlog.
Updates #16818
Change-Id: Icf6473a4823c9d35513bbd0c34ea02d5676d782a
Reviewed-on: https://go-review.googlesource.com/27471
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Bye bye one more class of linked list manipulation!
Change-Id: I2412b224c847dd640f9253125d30cd5f911ce00c
Reviewed-on: https://go-review.googlesource.com/27414
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Bso is already a member on ld.Link. Use that instead of
the global.
Updates #16818
Change-Id: Icfc0f6cb1ff551e8129253fb6b5e0d6a94479f51
Reviewed-on: https://go-review.googlesource.com/27470
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change threads the *ld.Link Ctxt variable through
code in arch-specific packages. This removes all remaining
uses of Ctxt, so remove the global variable too.
This CL continues the work in golang.org/cl/27408
Updates #16818
Change-Id: I5f4536847a1825fd0b944824e8ae4e122ec0fb78
Reviewed-on: https://go-review.googlesource.com/27459
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Ctxt is a global defined in cmd/link/internal/ld of type *ld.Link.
Start threading a *ld.Link through function calls instead of
relying on the global variable.
Ctxt is still used as a global by the architecture-specific packages,
but I plan to fix that in a subsequent CL.
Change-Id: I77a3a58bd396fafd959fa1d8b1c83008a9f5a7fb
Reviewed-on: https://go-review.googlesource.com/27408
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
I'd also like to document some of its fields, but I don't know
what they are.
Change-Id: I87d341e255f785d351a8a73e645be668e02b2689
Reviewed-on: https://go-review.googlesource.com/27399
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a copy of golang.org/cl/22092 by Ryan Brown.
Here's his original comment:
On my machine this increases the average time for 'go build cmd/go' from
2.25s to 2.36s. I tried to measure compile and link separately but saw
no significant change.
Change-Id: If0d2b756d52a0d30d4eda526929c82794d89dd7b
Reviewed-on: https://go-review.googlesource.com/25311
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
When dynamically linking, a type symbol's name is replaced with a name based on
the SHA1 of the name as type symbol's names can be very long. However, this
can make a type's symbol name longer in some cases. So skip it in that case.
One of the symbols this changes the treatment of is 'type.string' and that fixes a
bug where -X doesn't work when dynamically linking.
Fixes#16671
Change-Id: If5269038261b76fb0ec52e25a9c1d64129631e3c
Reviewed-on: https://go-review.googlesource.com/26890
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Access to globals requires a 2-instruction sequence on PIC 386.
MOVL foo(SB), AX
is translated by the obj package into:
CALL getPCofNextInstructionInTempRegister(SB)
MOVL (&foo-&thisInstruction)(tmpReg), AX
The call returns the PC of the next instruction in a register.
The next instruction then offsets from that register to get the
address required. The tricky part is the allocation of the
temp register. The legacy compiler always used CX, and forbid
the register allocator from allocating CX when in PIC mode.
We can't easily do that in SSA because CX is actually a required
register for shift instructions. (I think the old backend got away
with this because the register allocator never uses CX, only
codegen knows that shifts must use CX.)
Instead, we allow the temp register to be anything. When the
destination of the MOV (or LEA) is an integer register, we can
use that register. Otherwise, we make sure to compile the
operation using an LEA to reference the global. So
MOVL AX, foo(SB)
is never generated directly. Instead, SSA generates:
LEAL foo(SB), DX
MOVL AX, (DX)
which is then rewritten by the obj package to:
CALL getPcInDX(SB)
LEAL (&foo-&thisInstruction)(DX), AX
MOVL AX, (DX)
So this CL modifies the obj package to use different thunks
to materialize the pc into different registers. We use the
registers that regalloc chose so that SSA can still allocate
the full set of registers.
Change-Id: Ie095644f7164a026c62e95baf9d18a8bcaed0bba
Reviewed-on: https://go-review.googlesource.com/25442
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This adds 8 bytes of binary size to every type that has methods. It is
the smallest change I could come up with for 1.7.
Fixes#16037
Change-Id: Ibe15c3165854a21768596967757864b880dbfeed
Reviewed-on: https://go-review.googlesource.com/24070
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Functions should be declared to end after the last real instruction, not
after the last padding byte. We achieve this by adding the padding while
assembling the text section in the linker instead of adding the padding
to the function symbol in the compiler. This change makes dtrace happy.
TODO: check that this works with external linking
Fixes#15969
Change-Id: I973e478d0cd34b61be1ddc55410552cbd645ad62
Reviewed-on: https://go-review.googlesource.com/24040
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Adding a .def suffix for DWARF info collided with the DWARF info,
without the suffix, for a method named def. Change the suffix to ..def
instead.
Fixes#15926.
Change-Id: If1bf1bcb5dff1d7f7b79f78e3f7a3bbfcd2201bb
Reviewed-on: https://go-review.googlesource.com/23733
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
golang.org/issue/15443 complained that a race-enabled PIE binary crashed at
startup, but other ways of linking in tsan (or other sanitizers) such as
#cgo CFLAGS: -fsanitize=thread
#cgo LDFLAGS: -fsanitize=thread
have the same problem. Pass -no-pie to the host linker (if supported) if any
-fsanitizer=foo cgo LDFLAG is seen when linking.
Fixes#15887
Change-Id: Id799770f8d045f6f40fa8c463563937a5748d1a8
Reviewed-on: https://go-review.googlesource.com/23535
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This has a minor performance cost, but far less than is being gained by SSA.
As an experiment, enable it during the Go 1.7 beta.
Having frame pointers on by default makes Linux's perf, Intel VTune,
and other profilers much more useful, because it lets them gather a
stack trace efficiently on profiling events.
(It doesn't help us that much, since when we walk the stack we usually
need to look up PC-specific information as well.)
Fixes#15840.
Change-Id: I4efd38412a0de4a9c87b1b6e5d11c301e63f1a2a
Reviewed-on: https://go-review.googlesource.com/23451
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The offsets computed by the DWARF expressions for local variables
currently don't account for the extra stack slot used by the frame
pointer when GOEXPERIMENT=framepointer is enabled.
Fix this by adding the extra stack slot to the offset.
This fixes TestGdbPython with GOEXPERIMENT=framepointer.
Updates #15840.
Change-Id: I1b2ebb2750cd22266f4a89ec8d9e8bfa05fabd19
Reviewed-on: https://go-review.googlesource.com/23458
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
CL 23400 introduced a check to make sure the gold linker is used
on ARM host links. The check itself works, but the error checking
logic was reversed; fix it.
I manually verified that the check now correctly rejects host links
on my RPi2 running an ancient rasbian without the gold linker
installed.
Updates #15696
Change-Id: I927832620f0a60e91a71fdedf8cbd2550247b666
Reviewed-on: https://go-review.googlesource.com/23421
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This flag is experimental and the semantics may change
even after Go 1.7 is released. There are no changes to code
not using the flag.
The first part is for reading by future compiles.
The second part is for reading by the final link step.
Splitting the file this way allows distributed build systems
to ship the compile-input part only to compile steps and
the linker-input part only to linker steps.
The first part is basically just the export data,
and the second part is basically everything else.
The overall files still have the same broad structure,
so that existing tools will work with both halves.
It's just that various pieces are empty in the two halves.
This also copies the two bits of data the linker needed from
export data into the object header proper, so that the linker
doesn't need any export data at all. That eliminates a TODO
that was left for switching to the binary export data.
(Now the linker doesn't need to know about the switch.)
The default is still to write out a combined output file.
Nothing changes unless you pass -linkobj to the compiler.
There is no support in the go command for -linkobj,
since the go command doesn't copy objects around.
The expectation is that other build systems (like bazel, say)
might take advantage of this.
The header adjustment and the option for the split output
was intended as part of the zip archives, but the zip archives
have been cut from Go 1.7. Doing this to the current archives
both unblocks one step in the switch to binary export data
and enables alternate build systems to experiment with the
new flag using the Go 1.7 release.
Change-Id: I8b6eab25b8a22b0a266ba0ac6d31e594f3d117f3
Reviewed-on: https://go-review.googlesource.com/22500
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Currently 386 ELF binaries are generated with dynamic symbols that have
a size of zero bytes, even though the symbol in the symbol table has
the correct size. Fix this by specifying the correct size when creating
dynamic symbols.
Issue found on OpenBSD -current, where ld.so is now producing link
warnings due to mismatched symbol sizes.
Fixes#15593.
Change-Id: Ib1a12b23ff9159c61ac980bf48a983b86f3df256
Reviewed-on: https://go-review.googlesource.com/22912
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
I overlooked it when rebasing CL 19803.
Change-Id: Ife9d6bcc6a772715d137af903c64bafac0cdb216
Reviewed-on: https://go-review.googlesource.com/22797
Reviewed-by: Minux Ma <minux@golang.org>
Consider three shared libraries:
libBase.so -- defines a type T
lib2.so -- references type T
lib3.so -- also references type T, and something from lib2
lib2.so will contain a type symbol for T in its symbol table, but no
definition. If, when linking lib3.so the linker reads the symbols from lib2.so
before libBase.so, the linker didn't read the type data and later crashed.
The fix is trivial but the test change is a bit messy because the order the
linker reads the shared libraries in ends up depending on the order of the
import statements in the file so I had to rename one of the test packages so
that gofmt doesn't fix the test by accident...
Fixes#15516
Change-Id: I124b058f782c900a3a54c15ed66a0d91d0cde5ce
Reviewed-on: https://go-review.googlesource.com/22744
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The format has been tweaked several times in the latest cycle, so
replace go13ld with go17ld.
Change-Id: I343c49b02b7516fd781bc96ad46640579da68c59
Reviewed-on: https://go-review.googlesource.com/22708
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
a new relocation R_ADDRMIPSTLS is added, which resolves to 16-bit offset
of a TLS address on mips64x.
Change-Id: Ic60d0e1ba49ff1c433cead242f5884677ab227a5
Reviewed-on: https://go-review.googlesource.com/19804
Reviewed-by: Minux Ma <minux@golang.org>
SB register (R28) is introduced for access external addresses with shorter
instruction sequences. It is loaded at entry points. External data within
2G of SB can be accessed this way.
cmd/internal/obj: relocaltion R_ADDRMIPS is split into two relocations
R_ADDRMIPS and R_ADDRMIPSU, handling the low 16 bits and the "upper" 16
bits of external addresses, respectively, since the instructios may not
be adjacent. It might be better if relocation Variant could be used.
cmd/link/internal/mips64: support new relocations.
cmd/compile/internal/mips64: reserve SB register.
runtime: initialize SB register at entry points.
Change-Id: I5f34868f88c5a9698c042a8a1f12f76806c187b9
Reviewed-on: https://go-review.googlesource.com/19802
Reviewed-by: Minux Ma <minux@golang.org>
golang.org/cl/22453 was supposed to pass -no-pie to the linker when linking a
race-enabled binary if the host toolchain supports it. But I bungled the
supported check as I forgot to pass -c to the host compiler so it tried to
compile a 0 byte .c file into an executable, which will never work. Fix it to
pass -c as it should have all along.
Change-Id: I4801345c7a29cb18d5f22cec5337ce535f92135d
Reviewed-on: https://go-review.googlesource.com/22587
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Now it is possible to build a c-archive as PIC on darwin/arm (this is
now the default). Then the system linker can link the binary using
the archive as PIE.
Fixes#12896.
Change-Id: Iad84131572422190f5fa036e7d71910dc155f155
Reviewed-on: https://go-review.googlesource.com/22461
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Also adds TestGdbBacktrace to the runtime package.
Dwarf modifications written by Bryan Chan (@bryanpkc) who is also
at IBM and covered by the same CLA.
Fixes#14628
Change-Id: I106a1f704c3745a31f29cdadb0032e3905829850
Reviewed-on: https://go-review.googlesource.com/20193
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The linker was incorrectly decoding type name lengths, causing
typelinks to be sorted out of order and in cases where the name was
the exact right length, linker panics.
Added a test to the reflect package that causes TestTypelinksSorted
to fail before this CL. It's not the exact failure seen in #15448
but it has the same cause: decodetype_name calculating the wrong
length.
The equivalent decoders in reflect/type.go and runtime/type.go
have the parenthesis in the right place.
Fixes#15448
Change-Id: I33257633d812b7d2091393cb9d6cc8a73e0138c8
Reviewed-on: https://go-review.googlesource.com/22403
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Now that reflect.name objects contain an offset to pkgPath instead of a
pointer, there is no need to align the symbol data.
Removes approx. 10KB from the cmd/go binary. The effect becomes more
important later as more type data is moved into name objects.
For #6853
Change-Id: Idb507fdbdad04f16fc224378f82272cb5c236ab7
Reviewed-on: https://go-review.googlesource.com/21776
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Does anyone actually pass -a to the linker?
Change-Id: I1d31ea66aa5604b7fd42adf15bdab71e9f52d0ed
Reviewed-on: https://go-review.googlesource.com/22356
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reduces link time for cmd/go by 1%.
Change-Id: Iad4a16db0aedc56f81ddf73ba9b632e418dc1b19
Reviewed-on: https://go-review.googlesource.com/22242
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For the Solaris and S/390 builders.
Change-Id: Id9a83e0df91e6d0df8488ec5e2a546ba8e2d800e
Reviewed-on: https://go-review.googlesource.com/22327
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Michael Munday <munday@ca.ibm.com>
First (and largest single) step to switching cmd/link from linked
lists of symbols to slices.
Sort sections independently and concurrently.
This reduces jujud link times on linux/amd64 by ~4%.
Updates #15374
Change-Id: I452bc8f33081039468636502fe3c1cc8d6ed9efa
Reviewed-on: https://go-review.googlesource.com/22205
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Use (part of) a SHA-1 checksum to replace type symbol names.
In typical programs this has no effect because types are not included
in the symbol table. But when dynamically linking, types are in the
table to make sure there is only one *rtype per Go type.
Eventually we may be able to get rid of all pointers to rtype values in
the binary, but probably not by 1.7. And this has a nice effect on
binary size today:
libstd.so:
before 27.4MB
after 26.2MB
For #6853.
Change-Id: I603d7f3e5baad84f59f2fd37eeb1e4ae5acfe44a
Reviewed-on: https://go-review.googlesource.com/21583
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Instead of writing out the type almost twice in the symbol name,
teach the linker how to sort typelink symbols by their contents.
This ~halves the size of typelink symbol names, which helps very
large (6KB) names like those mentioned in #15104.
This does not increase the total sorting work done by the linker,
and makes it possible to use shorter symbol names for types. See
the follow-on CL 21583.
Change-Id: Ie5807565ed07d31bc477d20f60e4c0b47144f337
Reviewed-on: https://go-review.googlesource.com/21457
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The GNU linker follows the letter of -znocopyreloc by refusing to
generate COPY relocations on arm64. Unfortunately it generates an
error instead of finding another way. The gold linker works, so
switch to it.
Fixes linux/arm64 build.
Change-Id: I1f7119d999c8f9f1f2d0c1e06b6462cea9c02a71
Reviewed-on: https://go-review.googlesource.com/22185
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Introduce and start using nameOff for two encoded names. This pair
of changes is best done together because the linker's method decoder
expects the method layouts to match.
Precursor to converting all existing name and *string fields to
nameOff.
linux/amd64:
cmd/go: -45KB (0.5%)
jujud: -389KB (0.6%)
linux/amd64 PIE:
cmd/go: -170KB (1.4%)
jujud: -1.5MB (1.8%)
For #6853.
Change-Id: Ia044423f010fb987ce070b94c46a16fc78666ff6
Reviewed-on: https://go-review.googlesource.com/21396
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL introduces the typeOff type and a lookup method of the same
name that can turn a typeOff offset into an *rtype.
In a typical Go binary (built with buildmode=exe, pie, c-archive, or
c-shared), there is one moduledata and all typeOff values are offsets
relative to firstmoduledata.types. This makes computing the pointer
cheap in typical programs.
With buildmode=shared (and one day, buildmode=plugin) there are
multiple modules whose relative offset is determined at runtime.
We identify a type in the general case by the pair of the original
*rtype that references it and its typeOff value. We determine
the module from the original pointer, and then use the typeOff from
there to compute the final *rtype.
To ensure there is only one *rtype representing each type, the
runtime initializes a typemap for each module, using any identical
type from an earlier module when resolving that offset. This means
that types computed from an offset match the type mapped by the
pointer dynamic relocations.
A series of followup CLs will replace other *rtype values with typeOff
(and name/*string with nameOff).
For types created at runtime by reflect, type offsets are treated as
global IDs and reference into a reflect offset map kept by the runtime.
darwin/amd64:
cmd/go: -57KB (0.6%)
jujud: -557KB (0.8%)
linux/amd64 PIE:
cmd/go: -361KB (3.0%)
jujud: -3.5MB (4.2%)
For #6853.
Change-Id: Icf096fd884a0a0cb9f280f46f7a26c70a9006c96
Reviewed-on: https://go-review.googlesource.com/21285
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
After non pcln fields were added to it in a previous commit.
Change-Id: Icf92c0774d157c61399a6fc2a3c4d2cd47a634d2
Reviewed-on: https://go-review.googlesource.com/21921
Run-TryBot: Shahar Kohanim <skohanim@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
name old secs new secs delta
LinkCmdGo 0.53 ± 9% 0.53 ±10% -1.30% (p=0.022 n=100+99)
name old MaxRSS new MaxRSS delta
LinkCmdGo 151k ± 4% 142k ± 6% -5.92% (p=0.000 n=98+100)
Change-Id: Ic30e63a948f8e626b3396f458a0163f7234810c1
Reviewed-on: https://go-review.googlesource.com/21920
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This is the first in a series of CLs to replace the use of pointers
in binary read-only data with offsets.
In standard Go binaries these CLs have a small effect, shrinking
8-byte pointers to 4-bytes. In position-independent code, it also
saves the dynamic relocation for the pointer. This has a significant
effect on the binary size when building as PIE, c-archive, or
c-shared.
darwin/amd64:
cmd/go: -12KB (0.1%)
jujud: -82KB (0.1%)
linux/amd64 PIE:
cmd/go: -86KB (0.7%)
jujud: -569KB (0.7%)
For #6853.
Change-Id: Iad5625bbeba58dabfd4d334dbee3fcbfe04b2dcf
Reviewed-on: https://go-review.googlesource.com/21284
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Workaround external linking issues encountered on Solaris 11.2+ due to
the go.o object file being created with a NULL STT_FILE symtab entry by
using a placeholder name.
Fixes#14957
Change-Id: I89c501b4c548469f3c878151947d35588057982b
Reviewed-on: https://go-review.googlesource.com/21636
Reviewed-by: David Crawshaw <crawshaw@golang.org>
After making dwarf generation backed by LSyms there was a performance regression
of about 10%. These changes make on the fly symbol generation faster and
are meant to help mitigate that.
name old secs new secs delta
LinkCmdGo 0.55 ± 9% 0.53 ± 8% -4.42% (p=0.000 n=100+99)
name old MaxRSS new MaxRSS delta
LinkCmdGo 152k ± 6% 149k ± 3% -1.99% (p=0.000 n=99+97)
Change-Id: Iacca3ec924ce401aa83126bc0b10fe89bedf0ba6
Reviewed-on: https://go-review.googlesource.com/21733
Run-TryBot: Shahar Kohanim <skohanim@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Replace calls to bio.Bread with calls to io.ReadFull.
Change-Id: I2ee8739d01e04a4da9c20b6ce7d1d5b89914b8ad
Reviewed-on: https://go-review.googlesource.com/21750
Reviewed-by: Dave Cheney <dave@cheney.net>
Generated with honnef.co/go/unused
There is a large amount of unused code in cmd/internal/obj/s390x but
that can wait til the s390x port is merged.
There is some unused code in
cmd/internal/unvendor/golang.org/x/arch/arm/armasm but that should be
addressed upstream and a new revision imported.
Change-Id: I252c0f9ea8c5bb1a0b530a374ef13a0a20ea56aa
Reviewed-on: https://go-review.googlesource.com/21782
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dave Cheney <dave@cheney.net>
bio.BufReader was never used.
bio.BufWriter was used to wrap an existing io.Writer, but the
bio.Writer returned would not be seekable, so replace all occurences
with bufio.Reader instead.
Change-Id: I9c6779e35c63178aa4e104c17bb5bb8b52de0359
Reviewed-on: https://go-review.googlesource.com/21722
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a pre requesite of CL 21722 and removes a lot of unidiomatic
boilerplate in the linker.
Change-Id: If7491b88212b2be7b0c8c588e9c196839131f8ad
Reviewed-on: https://go-review.googlesource.com/21780
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Replace the bidirectional bio.Buf type with a pair of unidirectional
buffered seekable Reader and Writers.
Change-Id: I86664a06f93c94595dc67c2cbd21356feb6680ef
Reviewed-on: https://go-review.googlesource.com/21720
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
API could still be made more Go-ey.
Updates #15165.
Change-Id: I514ffceffa43c293ae5d7e5f1e9193fda0098865
Reviewed-on: https://go-review.googlesource.com/21644
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Two of these error messages are already dead code: cmd/compile.main
and cmd/link.main already switch on $GOARCH, ensuring it must be a
prefix of the sys.Arch.Family.
The error message about uncompiled Go source files can be just be
simplified: anyone who's manually constructing Go object file archives
probably knows what tool to use to compile Go source files.
Change-Id: Ia4a67c0a1d1158379c127c91e909226d3367f3c2
Reviewed-on: https://go-review.googlesource.com/21626
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Information about CPU architectures (e.g., name, family, byte
ordering, pointer and register size) is currently redundantly
scattered around the source tree. Instead consolidate the basic
information into a single new package cmd/internal/sys.
Also, introduce new sys.I386, sys.AMD64, etc. names for the constants
'8', '6', etc. and replace most uses of the latter. The notable
exceptions are a couple of error messages that still refer to the old
char-based toolchain names and function reltype in cmd/link.
Passes toolstash/buildall.
Change-Id: I8a6f0cbd49577ec1672a98addebc45f767e36461
Reviewed-on: https://go-review.googlesource.com/21623
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This updates dwarf.go to generate debug information as symbols
instead of directly writing to the output file. This should make
it easier to move generation of some of the debug info into the compiler.
Change-Id: Id2358988bfb689865ab4d68f82716f0676336df4
Reviewed-on: https://go-review.googlesource.com/20679
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
We already have variables to track whether the target platform is
64-bit vs 32-bit or RELA vs REL, so no point in repeating the list of
obscure architecture characters everywhere.
Passes toolstash/buildall.
Change-Id: I6a07f74188ac592ef229a7c65848a9ba93013cdb
Reviewed-on: https://go-review.googlesource.com/21569
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Counting the final buffer size usually doesn't result in the buffer growing,
so assume that it doesn't need to grow and only grow if necessary.
name old secs new secs delta
LinkCmdGo 0.49 ± 4% 0.48 ± 3% -1.31% (p=0.000 n=95+95)
name old MaxRSS new MaxRSS delta
LinkCmdGo 122k ± 4% 121k ± 5% ~ (p=0.065 n=96+100)
Change-Id: I85e7f5688a61ef5ef2b1b7afe56507e71c5bd5b1
Reviewed-on: https://go-review.googlesource.com/21509
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Shahar Kohanim <skohanim@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
To refer to types and names by offsets, we want to keep the symbols in
the same sections. Do this by making all types .relro for now.
Once name offsets are further along, name data can move out of relro.
Change-Id: I1cbd2e914bd180cdf25c4aeb13d9c1c734febe69
Reviewed-on: https://go-review.googlesource.com/21394
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Add supporting code for runtime initialization, including both
32- and 64-bit x86 architectures.
Add .ctors section on Windows to PE .o files, and INITENTRY to .ctors
section to plug in to the GCC C/C++ startup initialization mechanism.
This allows the Go runtime to initialize itself. Add .text section
symbol for .ctor relocations. Note: This is unlikely to be useful for
MSVC-based toolchains.
Fixes#13494
Change-Id: I4286a96f70e5f5228acae88eef46e2bed95813f3
Reviewed-on: https://go-review.googlesource.com/18057
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Rather than having half a dozen switch statements. Also remove some c2go dregs.
Change-Id: I19af5b64f73369126020e15421c34cad5bbcfbf8
Reviewed-on: https://go-review.googlesource.com/21442
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Change-Id: I91873aaebf79bdf1c00d38aacc1a1fb8d79656a7
Reviewed-on: https://go-review.googlesource.com/21433
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Introduces the new relocation variant RV_390_DBL which indicates
that the relocation value should be shifted right by 1 (to make
it 2-byte aligned).
Change-Id: I03fa96b4759ee19330c5298c3720746622fb1a03
Reviewed-on: https://go-review.googlesource.com/20878
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
In a number of places the code was joining filepaths explicitly with
"/", instead of using filepath.Join. This may cause problems on Windows
(or other) platforms.
This is in support of https://go-review.googlesource.com/#/c/18057
Change-Id: Ieb1334f35ddb2e125be690afcdadff8d7b0ace10
Reviewed-on: https://go-review.googlesource.com/21369
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
We create appropriate ELF files automatically based on GOOS. There's
no point in supporting -H elf flag, particularly since we need to emit
different flavors of ELF depending on GOOS anyway.
If that weren't reason enough, -H elf appears to be broken since at
least Go 1.4. At least I wasn't able to find a way to make use of it.
As best I can tell digging through commit history, -H elf is just an
artifact leftover from Plan 9's 6l linker.
Change-Id: I7393caaadbc60107bbd6bc99b976a4f4fe6b5451
Reviewed-on: https://go-review.googlesource.com/21343
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Record total number of relocations, pcdata, automatics, funcdata and files in
object file and use these numbers in the linker to allocate contiguous
slices to later be filled by the defined symbols.
name old secs new secs delta
LinkCmdGo 0.52 ± 3% 0.49 ± 3% -4.21% (p=0.000 n=91+92)
LinkJuju 4.48 ± 4% 4.21 ± 7% -6.08% (p=0.000 n=96+100)
name old MaxRSS new MaxRSS delta
LinkCmdGo 122k ± 2% 120k ± 4% -1.66% (p=0.000 n=98+93)
LinkJuju 799k ± 5% 865k ± 8% +8.29% (p=0.000 n=89+99)
GOGC=off
name old secs new secs delta
LinkCmdGo 0.42 ± 2% 0.41 ± 0% -2.98% (p=0.000 n=89+70)
LinkJuju 3.61 ± 0% 3.52 ± 1% -2.46% (p=0.000 n=80+89)
name old MaxRSS new MaxRSS delta
LinkCmdGo 130k ± 1% 128k ± 1% -1.33% (p=0.000 n=100+100)
LinkJuju 1.00M ± 0% 0.99M ± 0% -1.70% (p=0.000 n=100+100)
Change-Id: Ie08f6ccd4311bb78d8950548c678230a58635c73
Reviewed-on: https://go-review.googlesource.com/21026
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a change improving consistency in the source tree.
The pattern foo &= ^bar, was only used six times in src/ directory.
The usage of the supported &^ (bit clear / AND NOT) operator is way more
common, about factor 10x.
Change-Id: If26a2994fd81d23d42189bee00245eb84e672cf3
Reviewed-on: https://go-review.googlesource.com/21224
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
See #14874
This change tells the linker to collect all the itablink symbols and
collect them so that moduledata can have a slice of all compiler
generated itabs.
The logic is shamelessly adapted from what is done with typelink symbols.
Change-Id: Ie93b59acf0fcba908a876d506afbf796f222dbac
Reviewed-on: https://go-review.googlesource.com/20889
Reviewed-by: Keith Randall <khr@golang.org>
Calling the read only Linkrlookup will now not cause the name
string to escape. So a lookup can be performed on a []byte
casted to a string without allocating. This will help a followup
cl and it is also much simpler and cleaner.
Performance not impacted by this.
name old s/op new s/op delta
LinkCmdGo 0.51 ± 6% 0.51 ± 5% ~ (p=0.192 n=98+98)
Change-Id: I7846ba3160eb845a3a29cbf0be703c47369ece16
Reviewed-on: https://go-review.googlesource.com/21187
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Create a byte encoding designed for static Go names.
It is intended to be a compact representation of a name
and optional tag data that can be turned into a Go string
without allocating, and describes whether or not it is
exported without unicode table.
The encoding is described in reflect/type.go:
// The first byte is a bit field containing:
//
// 1<<0 the name is exported
// 1<<1 tag data follows the name
// 1<<2 pkgPath *string follow the name and tag
//
// The next two bytes are the data length:
//
// l := uint16(data[1])<<8 | uint16(data[2])
//
// Bytes [3:3+l] are the string data.
//
// If tag data follows then bytes 3+l and 3+l+1 are the tag length,
// with the data following.
//
// If the import path follows, then ptrSize bytes at the end of
// the data form a *string. The import path is only set for concrete
// methods that are defined in a different package than their type.
Shrinks binary sizes:
cmd/go: 164KB (1.6%)
jujud: 1.0MB (1.5%)
For #6853.
Change-Id: I46b6591015b17936a443c9efb5009de8dfe8b609
Reviewed-on: https://go-review.googlesource.com/20968
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Remove reflect type information for unexported methods that do not
satisfy any interface in the program.
Ideally the unexported method would not appear in the method list at
all, but that is tricky because the slice is built by the compiler.
Reduces binary size:
cmd/go: 81KB (0.8%)
jujud: 258KB (0.4%)
For #6853.
Change-Id: I25ef8df6907e9ac03b18689d584ea46e7d773043
Reviewed-on: https://go-review.googlesource.com/21033
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It was just a funny way of saying len(Ctxt.Allsym) by now.
Change-Id: Iff75e73c9f7ec4ba26cfef479bbd05d7dcd172f5
Reviewed-on: https://go-review.googlesource.com/20973
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Nothing cares about it.
I did this after looking at the memprof output, but it helps performance a bit:
name old s/op new s/op delta
LinkCmdGo 0.44 ± 3% 0.43 ± 3% -2.20% (p=0.000 n=94+90)
LinkJuju 3.98 ± 5% 3.94 ± 5% -1.19% (p=0.000 n=100+91)
As well as MaxRSS (i.e. what /usr/bin/time -f '%M' prints):
name old MaxRSS new MaxRSS delta
LinkCmdGo 130k ± 0% 120k ± 3% -7.79% (p=0.000 n=79+90)
LinkJuju 862k ± 6% 827k ± 8% -4.01% (p=0.000 n=100+99)
Change-Id: I6306b7b3369576a688659e2ecdb0815b4152ae96
Reviewed-on: https://go-review.googlesource.com/20972
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Debugasm can never be set in cmd/link, so delete it and the code it enables.
Change-Id: If828db0b09f1a9e512dc660ac2750657a769094c
Reviewed-on: https://go-review.googlesource.com/20971
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This expression in readsym:
dup != nil && len(dup.P) > 0 && strings.HasPrefix(s.Name, "gclocals·")
can never be true: if dup != nil, then s.Name is ".dup" (and this is not new:
the same broken logic is present in 1.4, at least). Delete the whole block.
Change-Id: I33b14d9a82b292116d6fd79d22b38e3842501317
Reviewed-on: https://go-review.googlesource.com/20970
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Another object file change, gives a reasonable improvement:
name old s/op new s/op delta
LinkCmdGo 0.46 ± 3% 0.44 ± 9% -3.34% (p=0.000 n=98+82)
LinkJuju 4.09 ± 4% 3.92 ± 5% -4.30% (p=0.000 n=98+99)
I guess the data section could be mmap-ed instead of read, I haven't tried
that.
Change-Id: I959eee470a05526ab1579e3f5d3ede41c16c954f
Reviewed-on: https://go-review.googlesource.com/20928
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reduces size of archives in pkg/linux_amd64 by 3% from 41.5MB to 40.2MB
Change-Id: Id64ca7995de8dd84c9e7ce1985730927cf4bfd66
Reviewed-on: https://go-review.googlesource.com/20912
Reviewed-by: David Crawshaw <crawshaw@golang.org>
When building shared libraries, all symbols on Allsym are marked reachable.
What I didn't realize was that this includes the ".dup" symbols created when
"dupok" symbols are read from multiple package files. This breaks now because
deadcode makes some assumptions that fail for these ".dup" symbols, but in any
case was a bad idea -- I suspect this change makes libstd.so a bunch smaller,
but creating it was broken before this CL so I can't be sure.
This change simply stops adding these symbols to Allsym, which might make some
of the many iterations over Allsym the linker does a touch quicker, although
that's not the motivation here.
Add a test that no symbols called ".dup" makes it into the runtime shared
library.
Fixes#14841
Change-Id: I65dd6e88d150a770db2d01b75cfe5db5fd4f8d25
Reviewed-on: https://go-review.googlesource.com/20780
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
