Change compiler and linker to emit DWARF lexical blocks in debug_info.
Version of debug_info is updated from DWARF v.2 to DWARF v.3 since version 2
does not allow lexical blocks with discontinuous ranges.
Second attempt at https://go-review.googlesource.com/#/c/29591/
Remaining open problems:
- scope information is removed from inlined functions
- variables in debug_info do not have DW_AT_start_scope attributes so a
variable will shadow other variables with the same name as soon as its
containing scope begins, before its declaration.
Updates golang/go#12899, golang/go#6913
Change-Id: I0e260a45b564d14a87b88974eb16c5387cb410a5
Reviewed-on: https://go-review.googlesource.com/36879
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
CL 38662 changed the x86 assembler to be eagerly
initialized, for a concurrent backend.
This CL puts in place a proper mechanism for doing so,
and switches all architectures to use it.
Passes toolstash-check -all.
Updates #15756
Change-Id: Id2aa527d3a8259c95797d63a2f0d1123e3ca2a1c
Reviewed-on: https://go-review.googlesource.com/39917
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
In a concurrent backend, Ctxt.Lookup will need some
form of concurrency protection, which will make it
more expensive.
This CL changes the pcln table builder to track
filenames as strings rather than LSyms.
Those strings are then converted into LSyms
at the last moment, for writing the object file.
This CL removes over 85% of the calls to Ctxt.Lookup
in a run of make.bash.
Passes toolstash-check.
Updates #15756
Change-Id: I3c53deff6f16f2643169f3bdfcc7aca2ca58b0a4
Reviewed-on: https://go-review.googlesource.com/39291
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Hwindowsgui has the same meaning as Hwindows - build PE
executable. So use Hwindows everywhere.
Change-Id: I2cae5777f17c7bc3a043dfcd014c1620cc35fc20
Reviewed-on: https://go-review.googlesource.com/38761
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Remove the global obj.Link.Curp.
In asmz.go, replace the only use by passing it as an argument.
In asm0.go and asm9.go, it was written but never read.
In asm5.go and asm7.go, thread it through as an argument.
Passes toolstash-check -all.
Updates #15756
Change-Id: I1a0faa89e768820f35d73a8b37ec8088d78d15f7
Reviewed-on: https://go-review.googlesource.com/38715
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
These fields are used to encode a single instruction.
Add them to AsmBuf, which is also per-instruction,
and which is not global.
Updates #15756
Change-Id: I0e5ea22ffa641b07291e27de6e2ff23b6dc534bd
Reviewed-on: https://go-review.googlesource.com/38668
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The x86 assembler requires a buffer to build
variable-length instructions.
It used to be an obj.Link field.
That doesn't play nicely with concurrent assembly.
Move the AsmBuf type to the x86 package,
where it belongs anyway,
and make it a local variable.
Passes toolstash-check -all.
No compiler performance impact.
Updates #15756
Change-Id: I8014e52145380bfd378ee374a0c971ee5bada917
Reviewed-on: https://go-review.googlesource.com/38663
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Asmode is always set to p.Mode,
which is always set based on the arch family.
Instead, use the arch family directly.
Passes toolstash-check -all.
Change-Id: Id982472dcc8eeb6dd22cac5ad2f116b54a44caee
Reviewed-on: https://go-review.googlesource.com/38451
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Replace Ctxt.Mode with a method, Ctxt.RegWidth,
which is calculated directly off the arch info.
I believe that Prog.Mode can also be removed; future CL.
This is a step towards obj.Link immutability.
Passes toolstash-check -all.
Updates #15756
Change-Id: Ifd7f8f6ed0a2fdc032d1dd306fcd695a14aa5bc5
Reviewed-on: https://go-review.googlesource.com/38446
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Shrinks LSym somewhat for non-STEXT LSyms, which are much more common.
While here, switch to tracking Automs in a slice instead of a linked
list. (Previously, this would have made LSyms larger.)
Passes toolstash-check.
Change-Id: I082e50e1d1f1b544c9e06b6e412a186be6a4a2b5
Reviewed-on: https://go-review.googlesource.com/37872
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Change-Id: I6343c162e27e2e492547c96f1fc504909b1c03c0
Reviewed-on: https://go-review.googlesource.com/37793
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For example, `-d pctab=pctoinline` prints the PC-inline table and
inlining tree for every function.
Change-Id: Ia6b9ce4d83eed0b494318d40ffe06481ec5d58ab
Reviewed-on: https://go-review.googlesource.com/37235
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The meaning of Version=1 was overloaded: it was reserved for file name
symbols (to avoid conflicts with non-file name symbols), but was also
used to mean "give me a fresh version number for this symbol."
With the new inlining tree, the same file name symbol can appear in
multiple entries, but each one would become a distinct symbol with its
own version number.
Now, we avoid duplicating symbols by using Version=0 for file name
symbols and we avoid conflicts with other symbols by prefixing the
symbol name with "gofile..".
Change-Id: I8d0374053b8cdb6a9ca7fb71871b69b4dd369a9c
Reviewed-on: https://go-review.googlesource.com/37234
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
In order to generate accurate tracebacks, the runtime needs to know the
inlined call stack for a given PC. This creates two tables per function
for this purpose. The first table is the inlining tree (stored in the
function's funcdata), which has a node containing the file, line, and
function name for every inlined call. The second table is a PC-value
table that maps each PC to a node in the inlining tree (or -1 if the PC
is not the result of inlining).
To give the appearance that inlining hasn't happened, the runtime also
needs the original source position information of inlined AST nodes.
Previously the compiler plastered over the line numbers of inlined AST
nodes with the line number of the call. This meant that the PC-line
table mapped each PC to line number of the outermost call in its inlined
call stack, with no way to access the innermost line number.
Now the compiler retains line numbers of inlined AST nodes and writes
the innermost source position information to the PC-line and PC-file
tables. Some tools and tests expect to see outermost line numbers, so we
provide the OutermostLine function for displaying line info.
To keep track of the inlined call stack for an AST node, we extend the
src.PosBase type with an index into a global inlining tree. Every time
the compiler inlines a call, it creates a node in the global inlining
tree for the call, and writes its index to the PosBase of every inlined
AST node. The parent of this node is the inlining tree index of the
call. -1 signifies no parent.
For each function, the compiler creates a local inlining tree and a
PC-value table mapping each PC to an index in the local tree. These are
written to an object file, which is read by the linker. The linker
re-encodes these tables compactly by deduplicating function names and
file names.
This change increases the size of binaries by 4-5%. For example, this is
how the go1 benchmark binary is impacted by this change:
section old bytes new bytes delta
.text 3.49M ± 0% 3.49M ± 0% +0.06%
.rodata 1.12M ± 0% 1.21M ± 0% +8.21%
.gopclntab 1.50M ± 0% 1.68M ± 0% +11.89%
.debug_line 338k ± 0% 435k ± 0% +28.78%
Total 9.21M ± 0% 9.58M ± 0% +4.01%
Updates #19348.
Change-Id: Ic4f180c3b516018138236b0c35e0218270d957d3
Reviewed-on: https://go-review.googlesource.com/37231
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Link.Plists never contained more than one Plist, and sometimes none.
Passing around the Plist being worked on is straightforward and makes
the data flow easier to follow.
Change-Id: I79cb30cb2bd3d319fdbb1dfa5d35b27fcb748e5c
Reviewed-on: https://go-review.googlesource.com/37169
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
In cmd/compile, we can directly construct obj.Auto to represent local
variables and attach them to the function's obj.LSym.
In preparation for being able to emit more precise DWARF info based on
other compiler available information (e.g., lexical scoping).
Change-Id: I9c4225ec59306bec42552838493022e0e9d70228
Reviewed-on: https://go-review.googlesource.com/36420
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
XPos is a compact (8 instead of 16 bytes on a 64bit machine) source
position representation. There is a 1:1 correspondence between each
XPos and each regular Pos, translated via a global table.
In some sense this brings back the LineHist, though positions can
track line and column information; there is a O(1) translation
between the representations (no binary search), and the translation
is factored out.
The size increase with the prior change is brought down again and
the compiler speed is in line with the master repo (measured on
the same "quiet" machine as for prior change):
name old time/op new time/op delta
Template 256ms ± 1% 262ms ± 2% ~ (p=0.063 n=5+4)
Unicode 132ms ± 1% 135ms ± 2% ~ (p=0.063 n=5+4)
GoTypes 891ms ± 1% 871ms ± 1% -2.28% (p=0.016 n=5+4)
Compiler 3.84s ± 2% 3.89s ± 2% ~ (p=0.413 n=5+4)
MakeBash 47.1s ± 1% 46.2s ± 2% ~ (p=0.095 n=5+5)
name old user-ns/op new user-ns/op delta
Template 309M ± 1% 314M ± 2% ~ (p=0.111 n=5+4)
Unicode 165M ± 1% 172M ± 9% ~ (p=0.151 n=5+5)
GoTypes 1.14G ± 2% 1.12G ± 1% ~ (p=0.063 n=5+4)
Compiler 5.00G ± 1% 4.96G ± 1% ~ (p=0.286 n=5+4)
Change-Id: Icc570cc60ab014d8d9af6976f1f961ab8828cc47
Reviewed-on: https://go-review.googlesource.com/34506
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This replaces the src.Pos LineHist-based position tracking with
the syntax.Pos implementation and updates all uses.
The LineHist table is not used anymore - the respective code is still
there but should be removed eventually. CL forthcoming.
Passes toolstash -cmp when comparing to the master repo (with the
exception of a couple of swapped assembly instructions, likely due
to different instruction scheduling because the line-based sorting
has changed; though this is won't affect correctness).
The sizes of various important compiler data structures have increased
significantly (see the various sizes_test.go files); this is probably
the reason for an increase of compilation times (to be addressed). Here
are the results of compilebench -count 5, run on a "quiet" machine (no
apps running besides a terminal):
name old time/op new time/op delta
Template 256ms ± 1% 280ms ±15% +9.54% (p=0.008 n=5+5)
Unicode 132ms ± 1% 132ms ± 1% ~ (p=0.690 n=5+5)
GoTypes 891ms ± 1% 917ms ± 2% +2.88% (p=0.008 n=5+5)
Compiler 3.84s ± 2% 3.99s ± 2% +3.95% (p=0.016 n=5+5)
MakeBash 47.1s ± 1% 47.2s ± 2% ~ (p=0.841 n=5+5)
name old user-ns/op new user-ns/op delta
Template 309M ± 1% 326M ± 2% +5.18% (p=0.008 n=5+5)
Unicode 165M ± 1% 168M ± 4% ~ (p=0.421 n=5+5)
GoTypes 1.14G ± 2% 1.18G ± 1% +3.47% (p=0.008 n=5+5)
Compiler 5.00G ± 1% 5.16G ± 1% +3.12% (p=0.008 n=5+5)
Change-Id: I241c4246cdff627d7ecb95cac23060b38f9775ec
Reviewed-on: https://go-review.googlesource.com/34273
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This will let us use the src.Pos struct to thread inlining
information through to obj.
Change-Id: I96a16d3531167396988df66ae70f0b729049cc82
Reviewed-on: https://go-review.googlesource.com/34195
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Introduce R_WEAKADDROFF, a "weak" variation of the R_ADDROFF relocation
that will only reference the type described if it is in some other way
reachable.
Use this for the ptrToThis field in reflect type information where it
is safe to do so (that is, types that don't need to be included for
interface satisfaction, and types that won't cause the compiler to
recursively generate an endless series of ptr-to-ptr-to-ptr-to...
types).
Also fix a small bug in reflect, where StructOf was not clearing the
ptrToThis field of new types.
Fixes#17931
Change-Id: I4d3b53cb9c916c97b3b16e367794eee142247281
Reviewed-on: https://go-review.googlesource.com/33427
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Instead of generating typelink symbols in the compiler
mark types that should have typelinks with a flag.
The linker detects this flag and adds the marked types
to the typelink table.
name old s/op new s/op delta
LinkCmdCompile 0.27 ± 6% 0.25 ± 6% -6.93% (p=0.000 n=97+98)
LinkCmdGo 0.30 ± 5% 0.29 ±10% -4.22% (p=0.000 n=97+99)
name old MaxRSS new MaxRSS delta
LinkCmdCompile 112k ± 3% 106k ± 2% -4.85% (p=0.000 n=100+100)
LinkCmdGo 107k ± 3% 103k ± 3% -3.00% (p=0.000 n=100+100)
Change-Id: Ic95dd4b0101e90c1fa262c9c6c03a2028d6b3623
Reviewed-on: https://go-review.googlesource.com/31772
Run-TryBot: Shahar Kohanim <skohanim@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The Gotype field is only used for ATYPE instructions. Instead of
specially storing the Go type symbol in From.Gotype, just store it in
To.Sym like any other 2-argument instruction would.
Modest reduction in allocations:
name old alloc/op new alloc/op delta
Template 42.0MB ± 0% 41.8MB ± 0% -0.40% (p=0.000 n=9+10)
Unicode 34.3MB ± 0% 34.1MB ± 0% -0.48% (p=0.000 n=9+10)
GoTypes 122MB ± 0% 122MB ± 0% -0.14% (p=0.000 n=9+10)
Compiler 518MB ± 0% 518MB ± 0% -0.04% (p=0.000 n=9+10)
Passes toolstash -cmp.
Change-Id: I0e603266b5d7d4e405106a26369e22773a0d3a91
Reviewed-on: https://go-review.googlesource.com/31850
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
ARM direct CALL/JMP instruction has 24 bit offset, which can only
encodes jumps within +/-32M. When the target is too far, the top
bits get truncated and the program jumps wild.
This CL detects too-far jumps and automatically insert trampolines,
currently only internal linking on ARM.
It is necessary to make the following changes to the linker:
- Resolve direct jump relocs when assigning addresses to functions.
this allows trampoline insertion without moving all code that
already laid down.
- Lay down packages in dependency order, so that when resolving a
inter-package direct jump reloc, the target address is already
known. Intra-package jumps are assumed never too far.
- a linker flag -debugtramp is added for debugging trampolines:
"-debugtramp=1 -v" prints trampoline debug message
"-debugtramp=2" forces all inter-package jump to use
trampolines (currently ARM only)
"-debugtramp=2 -v" does both
- Some data structures are changed for bookkeeping.
On ARM, pseudo DIV/DIVU/MOD/MODU instructions now clobber R8
(unfortunate). In the standard library there is no ARM assembly
code that uses these instructions, and the compiler no longer emits
them (CL 29390).
all.bash passes with -debugtramp=2, except a disassembly test (this
is unavoidable as we changed the instruction).
TBD: debug info of trampolines?
Fixes#17028.
Change-Id: Idcce347ea7e0af77c4079041a160b2f6e114b474
Reviewed-on: https://go-review.googlesource.com/29397
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Keep Plists in a slice instead of a linked list.
Eliminate unnecessary fields.
Also, while here remove gc's unused breakpc and continpc vars.
Change-Id: Ia04264036c0442843869965d247ccf68a5295115
Reviewed-on: https://go-review.googlesource.com/29367
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Replace the AGLOBL pseudo-op with a method to directly register an
LSym as a global. Similar to how we previously already replaced the
ADATA pseudo-op with directly writing out data bytes.
Passes toolstash -cmp.
Change-Id: I3631af0a2ab5798152d0c26b833dc309dbec5772
Reviewed-on: https://go-review.googlesource.com/29366
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Since the legacy backends were removed, these fields are write-only.
Change-Id: I4816c39267b7c10a4da2a6d22cd367dc475e564d
Reviewed-on: https://go-review.googlesource.com/29246
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Dave Cheney <dave@cheney.net>
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>
