It is now gone.
Change-Id: I59f68b324af706476695de2f291dd3aa5734e192
Reviewed-on: https://go-review.googlesource.com/c/go/+/351332
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
When internal linking with C objects, some C object relocations
may be turned into a CALL via PLT. For very large programs, the
PLT stub may be laid too far.
PLT stubs are generated late in the linker, and laid out after
the end of the text section. So if the text section is big, the
PLT stubs are likely too far.
To avoid this situation, add trampolines for PLT calls in the
trampoline pass. Only do this when the program is known too large
(i.e. the second pass of the two-pass algorithm).
Updates #40492.
Change-Id: I21f65d6cbc6bde84e3cf9c2ae05f5233df6cfa72
Reviewed-on: https://go-review.googlesource.com/c/go/+/314452
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Compared to ARM32 or PPC64, ARM64 has larger range for direct jumps.
But for very large programs it can still go over the limit. Add
trampoline insertion for ARM64.
Updates #40492.
Change-Id: Id97301dbc35fb577ba3f8d5f3316a8424d4f53c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/314451
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
PPC64 needs to preserve bits when applying some relocations. DS form
relocations must preserve the lower two bits, and thus needs to inspect
the section data as it streams out.
Similarly, the overflow checking requires inspecting the primary
opcode to see if the value is sign or zero extended.
The existing PPC64 code no longer works as the slice returned by
(loader*).Data is cleared as we layout the symbol and process
relocations. This data is always the section undergoing relocation,
thus we can directly inspect the contents to preserve bits or
check for overflows.
Change-Id: I239211f7e5e96208673663b6553b3017adae7e01
Reviewed-on: https://go-review.googlesource.com/c/go/+/300555
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
This CL is part of a stack adding windows/arm64
support (#36439), intended to land in the Go 1.17 cycle.
Change-Id: I397c1d238bb18cbe78b3fca00910660cf1d66b8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/288822
Trust: Russ Cox <rsc@golang.org>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Mach-O relocation addend is signed 24-bit. When external linking,
if the addend is larger, we cannot put it directly into a Mach-O
relocation. This CL handles large addend by creating "label"
symbols at sym+0x800000, sym+(0x800000*2), etc., and emitting
Mach-O relocations that target the label symbols with a smaller
addend. The label symbols are generated late (similar to what
we do for RISC-V64).
One complexity comes from handling of carrier symbols, which does
not track its size or its inner symbols. But relocations can
target them. We track them in a side table (similar to what we
do for XCOFF, xcoffUpdateOuterSize).
Fixes#42738.
Change-Id: I8c53ab2397f8b88870d26f00e9026285e5ff5584
Reviewed-on: https://go-review.googlesource.com/c/go/+/278332
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Mach-O relocation addend is signed 24-bit. If the addend
overflows, it is better to fail the build than emitting an
incorrect binary. (I'm still working on a fix.)
Updates #42738.
Change-Id: I647f0cd4f6b84d9ac75ef3bf36673bea01dfc211
Reviewed-on: https://go-review.googlesource.com/c/go/+/276694
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>
The linker already has R_AARCH64_LDST{8,32,64,128}_ABS_LO12_NC, some cgo tests require
R_AARCH64_LDST16_ABS_LO12_NC, this CL adds this relocation type.
Fixes#42660
Change-Id: I9a5120cd872f5095c61175cb602427c6ab3225cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/271017
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: eric fang <eric.fang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: eric fang <eric.fang@arm.com>
Trust: Benny Siegert <bsiegert@gmail.com>
This reverts CL 252478.
Reason for revert: debug/Elfhdr has no Flags fields, some other CLs has removed it.
Change-Id: Ie199ac29f382c56aaf37a2e8338f2dafe6e79297
Reviewed-on: https://go-review.googlesource.com/c/go/+/265317
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Meng Zhuo <mzh@golangcn.org>
Cgo programs work as well. Still not enabled by default for now.
Enable internal linking tests.
Updates #38485.
Change-Id: I8324a5c263fba221eb4e67d71207ca84fa241e6c
Reviewed-on: https://go-review.googlesource.com/c/go/+/263637
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Handle calls to symbols that are SDYNIMPORT when linking internally on arm64.
Update #36435
Change-Id: I8b5421171bf471cf31c91d90b8ba99511d2c9e2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/250181
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Add support of internal linking on darwin/arm64 (macOS).
Still incomplete. Pure Go binaries work. Cgo doesn't. TLS is not
set up when cgo is not used (as before) (so asynchronous
preemption is not enabled).
Internal linking is not enabled by default but can be requested
via -ldflags=-linkmode=internal.
Updates #38485.
Change-Id: I1e0c81b6028edcb1ac26dcdafeb9bb3f788cf732
Reviewed-on: https://go-review.googlesource.com/c/go/+/261643
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Rename Reloc2 to Reloc, At2 to At, Aux2 to Aux.
Change-Id: Ic98d83c080e8cd80fbe1837c8f0aa134033508ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/245578
Reviewed-by: Jeremy Faller <jeremy@golang.org>
We have Reloc and Reloc2. Reloc2 is the better approach and most
code uses Reloc2. There are still uses of Reloc. This CL migrates
them to Reloc2, and removes Reloc.
Change-Id: Id5f6a6019e1e044add682d05e70ebb1548ec58d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/245577
Reviewed-by: Jeremy Faller <jeremy@golang.org>
We used to generate all external relocations in memory, then emit
the relocation records at a later pass. The data structures were
chosen so that it takes as little memory as possible. Now we just
stream out external relocations, and ExtReloc is just a local
variable. Change the data structure to avoid repeated read of
some fields. Also get rid of ExtRelocView, as it is no longer
necessary.
Change-Id: I40209bbe4387af231b29788125c3b4ebb0ff4a33
Reviewed-on: https://go-review.googlesource.com/c/go/+/245479
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
The previous CL changed it to drop the Data when writing out a
symbol. Don't read the data.
Fix ARM64 build.
Change-Id: I121e9b0ebef123dbbc4ddffc02bf1a42788532f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/244038
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Support streaming external relocations on ARM64. Support
architecture-specific relocations.
Also support streaming external relocations on Darwin. Do it in
the same CL so ARM64's archreloc doesn't need to support both
streaming and non-streaming.
Change-Id: Ia7fee9957892f98c065022c69a51f47402f4d6e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/243644
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Following CL 240399 and CL 240400, do the same for Mach-O.
Linking cmd/compile with external linking,
name old time/op new time/op delta
Asmb2_GC 32.7ms ± 2% 13.5ms ± 6% -58.56% (p=0.008 n=5+5)
name old alloc/op new alloc/op delta
Asmb2_GC 16.5MB ± 0% 6.4MB ± 0% -61.15% (p=0.008 n=5+5)
Change-Id: I0fd7019d8713d1940e5fbbce4ee8eebd926451a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/241178
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
In CL 240399 we changed to precompute the size for ELF relocation
records and use mmap to write them, but we left architectures
where elfreloc1 write non-fixed number of bytes. This CL handles
those architectures. When a Go relocation will turn into multiple
ELF relocations, in relocsym we account this difference and add
it to the size calculation. So when emitting ELF relocations, we
know the number of ELF relocations to be emitted.
Change-Id: I6732ab674b442f4618405e5412a77f6e4a3315d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/241079
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Now that we write ELF relocation records in mapped memory with
known sizes and offsets, we can write them in parallel.
Further speed up Asmb2 pass. Linking cmd/compile with external
linking,
Asmb2 141ms ± 4% 97ms ± 5% -30.98% (p=0.000 n=10+9)
Change-Id: I52c2b9230e90ed4421c21d7ef13a4f1e996f6054
Reviewed-on: https://go-review.googlesource.com/c/go/+/240400
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
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
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>
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>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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>
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>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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>
Switch to using loader interfaces for the arm64 version of
archreloc.
Change-Id: I12608a95d27622a7d578a2943a35fa8c89c11d52
Reviewed-on: https://go-review.googlesource.com/c/go/+/232201
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The arm64 archreloc method contains a workaround for a 2015-era
binutils/linker bug, https://sourceware.org/bugzilla/show_bug.cgi?id=18270.
This bug has been fixed for some time now, so remove the workaround
for it (the workaround includes some code that mutates a relocation
type, which is something we want to void doing in the new linker).
Change-Id: I9b7584e4daad240bbb85de673d704731705c8148
Reviewed-on: https://go-review.googlesource.com/c/go/+/232200
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Add code to the loader to enforce the invariant that there is only a
single level of 'outer' symbol nesting. That is, if outer(X) = Y, then
outer(Y) is always zero.
Revise foldSubSymbolOffset based on the new invariant, allowing it to
be inlined, and then fix the various "for s.Outer != nil" loops in the
linker to just use an "if" instead of a loop.
Change-Id: Ib895702bc6de52718248f09a5368b84cb2e0a3fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/231137
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Currently, for external relocations, the ExtReloc structure
contains all the fields of the relocation. In fact, many of the
fields are the same with the original relocation. So, instead, we
can just use an index to reference the original relocation and
not expand the fields.
There is one place where we modify relocation type: changing
R_DWARFSECTREF to R_ADDR. Get away with it by changing
downstreams.
It also makes it easier to retrieve the reloc variant.
This reduces some allocation. Linking cmd/compile with external
linking,
name old alloc/op new alloc/op delta
Reloc_GC 34.1MB ± 0% 22.7MB ± 0% -33.30% (p=0.000 n=5+4)
Change-Id: Id08a89ed2aee705296886d3b95014b806a0d55cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/231217
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>
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>
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>
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>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Add elf/ARM arch support for the new dodata() phase.
Change-Id: Iadd772b01036c6c5be95bcc6017f6c05d45a24c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/229868
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Recreation of CL 228317.
The problem with that original CL was a late requested change,
reordering reloc and asmb, resulting in symbols having stale pointers to
their data. I've fixed this by preallocating the heap variable in OutBuf
for platforms w/o mmap.
Change-Id: Icdb392ac2c8d6518830f4c84cf422e78b8ab68c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/228782
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
