Robert Griesemer [Wed, 16 Mar 2016 21:02:56 +0000 (14:02 -0700)]
cmd/compile: remove dead code handling '~' operator
The parser code was not reachable ever since some of the lexer cleanups.
We could recognize '~' in the lexer, complain, and return a '^' instead,
but it's been a few years since Go was new and this may have been a use-
ful error. The lexer complains with "illegal character U+007E '~'" which
is good enough.
For #13244.
Change-Id: Ie3283738486eb6f8462d594f2728ac98333c0520
Reviewed-on: https://go-review.googlesource.com/20768 Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Change-Id: I9623a40ff0d568f11afd1279b6aaa1c33eda644c
Reviewed-on: https://go-review.googlesource.com/20730 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Austin Clements [Mon, 15 Feb 2016 23:30:48 +0000 (18:30 -0500)]
runtime: shrink stacks during concurrent mark
Currently we shrink stacks during STW mark termination because it used
to be unsafe to shrink them concurrently. For some programs, this
significantly increases pause time: stack shrinking costs ~5ms/MB
copied plus 2µs/shrink.
Now that we've made it safe to shrink a stack without the world being
stopped, shrink them during the concurrent mark phase.
This reduces the STW time in the program from issue #12967 by an order
of magnitude and brings it from over the 10ms goal to well under:
name old 95%ile-markTerm-time new 95%ile-markTerm-time delta
Stackshrink-4 23.8ms ±60% 1.80ms ±39% -92.44% (p=0.008 n=5+5)
Fixes #12967.
This slows down the go1 and garbage benchmarks overall by < 0.5%.
name old time/op new time/op delta
XBenchGarbage-12 2.48ms ± 1% 2.49ms ± 1% +0.45% (p=0.005 n=25+21)
Austin Clements [Mon, 15 Feb 2016 23:24:06 +0000 (18:24 -0500)]
runtime: generalize work.finalizersDone to work.markrootDone
We're about to add another root marking job that needs to happen only
during the first markroot pass (whether that's concurrent or STW),
just like finalizer scanning. Rather than introducing another flag
that has the same value as finalizersDone, just rename finalizersDone
to markrootDone.
Austin Clements [Mon, 15 Feb 2016 22:38:06 +0000 (17:38 -0500)]
runtime: make shrinkstack concurrent-safe
Currently shinkstack is only safe during STW because it adjusts
channel-related stack pointers and moves send/receive stack slots
without synchronizing with the channel code. Make it safe to use when
the world isn't stopped by:
1) Locking all channels the G is blocked on while adjusting the sudogs
and copying the area of the stack that may contain send/receive
slots.
2) For any stack frames that may contain send/receive slot, using an
atomic CAS to adjust pointers to prevent races between adjusting a
pointer in a receive slot and a concurrent send writing to that
receive slot.
In principle, the synchronization could be finer-grained. For example,
we considered synchronizing around the sudogs, which would allow
channel operations involving other Gs to continue if the G being
shrunk was far enough down the send/receive queue. However, using the
channel lock means no additional locks are necessary in the channel
code. Furthermore, the stack shrinking code holds the channel lock for
a very short time (much less than the time required to shrink the
stack).
This does not yet make stack shrinking concurrent; it merely makes
doing so safe.
This has negligible effect on the go1 and garbage benchmarks.
Austin Clements [Sun, 21 Feb 2016 15:40:39 +0000 (10:40 -0500)]
runtime: define lock order between G status and channel lock
Currently, locking a G's stack by setting its status to _Gcopystack or
_Gscan is unordered with respect to channel locks. However, when we
make stack shrinking concurrent, stack shrinking will need to lock the
G and then acquire channel locks, which imposes an order on these.
Document this lock ordering and fix closechan to respect it.
Everything else already happens to respect it.
Austin Clements [Thu, 18 Feb 2016 14:34:43 +0000 (09:34 -0500)]
runtime: protect sudog.elem with hchan.lock
Currently sudog.elem is never accessed concurrently, so in several
cases we drop the channel lock just before reading/writing the
sent/received value from/to sudog.elem. However, concurrent stack
shrinking is going to have to adjust sudog.elem to point to the new
stack, which means it needs a way to synchronize with accesses to
sudog.elem. Hence, add sudog.elem to the fields protected by
hchan.lock and scoot the unlocks down past the uses of sudog.elem.
While we're here, better document the channel synchronization rules.
Austin Clements [Thu, 25 Feb 2016 20:37:40 +0000 (15:37 -0500)]
runtime: fix transient _Gwaiting states in newstack
With concurrent stack shrinking, the stack can move the instant after
a G enters _Gwaiting. There are only two places that put a G into
_Gwaiting: gopark and newstack. We fixed uses of gopark. This commit
fixes newstack by simplifying its G transitions and, in particular,
eliminating or narrowing the transient _Gwaiting states it passes
through so it's clear nothing in the G is accessed while in _Gwaiting.
Austin Clements [Fri, 26 Feb 2016 15:50:54 +0000 (10:50 -0500)]
runtime: never pass stack pointers to gopark
gopark calls the unlock function after setting the G to _Gwaiting.
This means it's generally unsafe to access the G's stack from the
unlock function because the G may start running on another P. Once we
start shrinking stacks concurrently, a stack shrink could also move
the stack the moment after it enters _Gwaiting and before the unlock
function is called.
Document this restriction and fix the two places where we currently
violate it.
This is unlikely to be a problem in practice for these two places
right now, but they're already skating on thin ice. For example, the
following sequence could in principle cause corruption, deadlock, or a
panic in the select code:
On M1/P1:
1. G1 selects on channels A and B.
2. selectgoImpl calls gopark.
3. gopark puts G1 in _Gwaiting.
4. gopark calls selparkcommit.
5. selparkcommit releases the lock on channel A.
On M2/P2:
6. G2 sends to channel A.
7. The send puts G1 in _Grunnable and puts it on P2's run queue.
8. The scheduler runs, selects G1, puts it in _Grunning, and resumes G1.
9. On G1, the sellock immediately following the gopark gets called.
10. sellock grows and moves the stack.
On M1/P1:
11. selparkcommit continues to scan the lock order for the next
channel to unlock, but it's now reading from a freed (and possibly
reused) stack.
This shouldn't happen in practice because step 10 isn't the first call
to sellock, so the stack should already be big enough. However, once
we start shrinking stacks concurrently, this reasoning won't work any
more.
Austin Clements [Tue, 16 Feb 2016 16:06:00 +0000 (11:06 -0500)]
runtime: put g.waiting list in lock order
Currently the g.waiting list created by a select is in poll order.
However, nothing depends on this, and we're going to need access to
the channel lock order in other places shortly, so modify select to
put the waiting list in channel lock order.
For #12967.
Change-Id: If0d38816216ecbb37a36624d9b25dd96e0a775ec
Reviewed-on: https://go-review.googlesource.com/20037 Reviewed-by: Rick Hudson <rlh@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
Austin Clements [Tue, 16 Feb 2016 04:50:58 +0000 (23:50 -0500)]
runtime: use indexes for select lock order
Currently the select lock order is a []*hchan. We're going to need to
refer to things other than the channel itself in lock order shortly,
so switch this to a []uint16 of indexes into the select cases. This
parallels the existing representation for the poll order.
Change-Id: I89262223fe20b4ddf5321592655ba9eac489cda1
Reviewed-on: https://go-review.googlesource.com/20036 Reviewed-by: Rick Hudson <rlh@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Austin Clements [Mon, 15 Feb 2016 22:37:04 +0000 (17:37 -0500)]
runtime: record channel in sudog
Given a G, there's currently no way to find the channel it's blocking
on. We'll need this information to fix a (probably theoretical) bug in
select and to implement concurrent stack shrinking, so record the
channel in the sudog.
Austin Clements [Mon, 14 Mar 2016 17:51:23 +0000 (13:51 -0400)]
runtime: perform gcMarkRootCheck during STW in checkmark mode
gcMarkRootCheck is too expensive to do during mark termination.
However, since it's a useful check and it complements checkmark mode
nicely, enable it during mark termination is checkmark is enabled.
Brad Fitzpatrick [Wed, 16 Mar 2016 18:26:43 +0000 (18:26 +0000)]
net/http: use dynamic type assertion to remove HTTP server code from cmd/go
I was wondering why cmd/go includes the HTTP server implementations.
Dumping the linker's deadcode dependency graph into a file and doing
some graph analysis, I found that the only reason cmd/go included an
HTTP server was because the maxBytesReader type (used by both the HTTP
transport & HTTP server) did a static type assertion to an HTTP server
type.
Changing it to a interface type assertion reduces the size of cmd/go
by 533KB (5.2%)
Add a test too so this doesn't regress. The test uses cmd/go as the
binary to test (a binary which needs the HTTP client but not the HTTP
server), but this change and test are equally applicable to any such
program.
Robert Griesemer [Wed, 16 Mar 2016 02:06:00 +0000 (19:06 -0700)]
cmd/compile: faster parameter parsing with no OKEY nodes
Step 2 of stream-lining parameter parsing
- do parameter validity checks in parser
- two passes instead of multiple (and theoretically quadratic) passes
when checking parameters
- removes the need for OKEY and some ONONAME nodes in those passes
This removes allocation of ~123K OKEY (incl. some ONONAME) nodes
out of a total of ~10M allocated nodes when running make.bash, or
a reduction of the number of alloacted nodes by ~1.2%.
Change-Id: I4a8ec578d0ee2a7b99892ac6b92e56f8e0415f03
Reviewed-on: https://go-review.googlesource.com/20748 Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
Martin Möhrmann [Tue, 8 Mar 2016 19:13:58 +0000 (20:13 +0100)]
fmt: reuse buffer and add range checks for %c and %q
Use The fmt internal buffer for character formatting instead of
the pp Printer rune decoding buffer.
Uses an uint64 instead of int64 argument to fmt_c and fmt_qc for easier
range checks since no valid runes are represented by negative numbers or
are above 0x10ffff.
Add range checks to fmt_c and fmt_qc to guarantee that a RuneError
character is returned by the functions for any invalid code point
in range uint64. For invalid code points in range utf8.MaxRune
the used utf8 and strconv functions already return a RuneError.
Change-Id: I9772f804dfcd79c3826fa7f6c5ebfbf4b5304a51
Reviewed-on: https://go-review.googlesource.com/20373
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Martin Möhrmann [Sat, 12 Mar 2016 12:53:19 +0000 (13:53 +0100)]
fmt: cleanup %p and %T code paths
Remove check for %p and %T in printValue.
These verbs are not recursive and are handled already in
printArg which is called on any argument before printValue.
Format the type string for %T directly instead of invoking
the more complex printArg with %s on the type string.
Decouple the %T tests from variables declared in scan_test.go.
Change-Id: Ibd51566bd4cc1a260ce6d052f36382ed05020b48
Reviewed-on: https://go-review.googlesource.com/20622
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Mikio Hara [Tue, 15 Mar 2016 01:00:12 +0000 (10:00 +0900)]
net: filter destination addresses when source address is specified
This change filters out destination addresses by address family when
source address is specified to avoid running Dial operation with wrong
addressing scopes.
Fixes #11837.
Change-Id: I10b7a1fa325add2cd8ed58f105d527700a10d342
Reviewed-on: https://go-review.googlesource.com/20586 Reviewed-by: Paul Marks <pmarks@google.com>
Mikio Hara [Wed, 9 Mar 2016 09:16:00 +0000 (18:16 +0900)]
net: prevent spurious TCP connection setup notification on darwin
On the latest darwin kernels, kevent in runtime-integrated network
poller sometimes reports SYN-SENT state sockets as ESTABLISHED ones,
though it's still unclear what's the root cause.
This change prevents such spurious notifications by additional connect
system calls.
Fixes #14548.
Change-Id: Ie29788e38ca735ca77259befeba3229d6a30ac52
Reviewed-on: https://go-review.googlesource.com/20468
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Martin Möhrmann [Thu, 10 Mar 2016 15:11:35 +0000 (16:11 +0100)]
fmt: replace variables for type bit sizes with constants
Use constants instead of dynamically computed values to determine
the bit sizes of types similar to how strconv and other packages
directly compute these sizes. Move these constants near the code
that uses them.
Change-Id: I78d113b7e697466097e32653975df5990380c2c1
Reviewed-on: https://go-review.googlesource.com/20514
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Matthew Dempsky [Tue, 15 Mar 2016 20:06:58 +0000 (13:06 -0700)]
cmd: collapse internal/obj/fmt.go into compile/internal/gc/fmt.go
The obj.Fmt* values are only used by gc/fmt.go, so just move them
there. Also, add comments documenting the correspondance between
FmtFoo names and their flag characters to make understanding the
existing documentation slightly less confusing.
While here, add a new FmtFlag named type to represent these values.
Wedson Almeida Filho [Sun, 24 Jan 2016 18:23:48 +0000 (19:23 +0100)]
sync: new Cond implementation
Change Cond implementation to use a notification list such that waiters
can first register for a notification, release the lock, then actually
wait. Signalers never have to park anymore.
This is intended to address an issue in the previous implementation
where Broadcast could fail to signal all waiters.
Caleb Spare [Mon, 14 Mar 2016 00:59:26 +0000 (17:59 -0700)]
encoding/base64: correct DecodedLen overestimate for unpadded encodings
While we're at it, add tests for EncodedLen and DecodedLen.
Fixes #14803.
Change-Id: I200c72cf11c51669b8d9f70c6e57ece359f7ae61
Reviewed-on: https://go-review.googlesource.com/20649 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
David Crawshaw [Tue, 15 Mar 2016 01:30:43 +0000 (21:30 -0400)]
cmd/compile: compute second method type at runtime
The type information for a method includes two variants: a func
without the receiver, and a func with the receiver as the first
parameter. The former is used as part of the dynamic interface
checks, but the latter is only returned as a type in the
reflect.Method struct.
Instead of computing it at compile time, construct it at run time
with reflect.FuncOf.
Using cl/20701 as a baseline,
cmd/go: -480KB, (4.4%)
jujud: -5.6MB, (7.8%)
For #6853.
Change-Id: I1b8c73f3ab894735f53d00cb9c0b506d84d54e92
Reviewed-on: https://go-review.googlesource.com/20709
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Matthew Dempsky [Mon, 14 Mar 2016 19:45:18 +0000 (12:45 -0700)]
cmd/compile: use int for field index
All of a struct's fields have to fit into memory anyway, so index them
with int instead of int64. This also makes it nicer for
cmd/compile/internal/gc to reuse the same NumFields function.
Change-Id: I210be804a0c33370ec9977414918c02c675b0fbe
Reviewed-on: https://go-review.googlesource.com/20691 Reviewed-by: Ian Lance Taylor <iant@golang.org>
David Crawshaw [Mon, 14 Mar 2016 19:08:22 +0000 (15:08 -0400)]
cmd/link: when pruning methods also prune funcType
Remove method type information for pruned methods from any program
that does not reflect on methods. This can be a significant saving:
addr2line: -310KB (8.8%)
A future update might want to consider a more aggressive variant of
this: setting the Type and Func fields of reflect.Method to nil for
unexported methods. That would shrink cmd/go by 2% and jujud by 2.6%
but could be considered an API change. So this CL sticks to the
uncontroversial change.
For #6853.
Change-Id: I5d186d9f822dc118ee89dc572c4912a3b3c72577
Reviewed-on: https://go-review.googlesource.com/20701
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Russ Cox [Mon, 14 Mar 2016 01:34:46 +0000 (21:34 -0400)]
os/user: allow LookupGroupId to fail during test
On my Mac I am in group 5000 which apparently has no name
(I suspect because it is an LDAP group and I cannot reach the
LDAP server). Do not make the test fail in that case.
Shahar Kohanim [Mon, 14 Mar 2016 20:57:58 +0000 (22:57 +0200)]
cmd/link, cmd/compile: Add symbol references to object file.
Symbols in the object file currently refer to each other using symbol name
and version. Referring to the same symbol many times in an object file takes
up space and causes redundant map lookups. Instead write out a list of unique
symbol references and have symbols refer to each other using indexes into this
list.
Credit to Michael Hudson-Doyle for kicking this off.
Reduces pkg/linux_amd64 size by 30% from 61MB to 43MB
name old s/op new s/op delta
LinkCmdGo 0.74 ± 3% 0.63 ± 4% -15.22% (p=0.000 n=20+20)
LinkJuju 6.38 ± 6% 5.73 ± 6% -10.16% (p=0.000 n=20+19)
Change-Id: I7e101a0c80b8e673a3ba688295e6f80ea04e1cfb
Reviewed-on: https://go-review.googlesource.com/20099 Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
CL 14603 attempted to preserve the callee-save registers for
the darwin/arm runtime initialization routine, but I believe it
wasn't sufficient and resulted in the crash reported in issue
Saving and restoring the registers on the stack the same way
linux/arm does seems more obvious and fixes #14778, so do that.
Even though #14778 is not reproducible on darwin/arm64, I applied
a similar change there, and to linux/arm64 which obeys the same
calling convention.
Finally, this CL is a candidate for a 1.6 minor release for the same
reason CL 14603 was in a 1.5 minor release (as CL 16968). It is
small and only touches the iOS platforms and gomobile on darwin/arm
is currently useless without it.
Fixes #14778
Fixes #12590 (again)
Change-Id: I7401daf0bbd7c579a7e84761384a7b763651752a
Reviewed-on: https://go-review.googlesource.com/20621 Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Jeremy Jackins [Sun, 13 Mar 2016 01:23:18 +0000 (10:23 +0900)]
cmd/compile: clean up C-style variable declarations in plive.go
Change-Id: I928f51a1fe4830a81d4f5d3eb572785e06a75b77
Reviewed-on: https://go-review.googlesource.com/20581 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Matthew Dempsky [Mon, 14 Mar 2016 07:24:43 +0000 (00:24 -0700)]
cmd/compile: stop storing TFIELD types in Node.Type
Currently, the only use for this is on the Left side of OKEY nodes
within struct literals. esc and fmt only care so they can recognize
that the ONAME nodes are actually field names, which need special
handling.
sinit additionally needs to know the field's offset within the struct,
which we can provide via Xoffset.
Passes toolstash/buildall.
Change-Id: I362d965e161f4d80fcd9c9bae0dfacc657dc0b29
Reviewed-on: https://go-review.googlesource.com/20676 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Change-Id: Idc63c41b2be2d52e3a6ac59b3a12eb41aa2efbed
Reviewed-on: https://go-review.googlesource.com/20670 Reviewed-by: Ian Lance Taylor <iant@golang.org>
String symbols' names used to appear in the final binary.
Using a string's contents as it's symbol's name
was a thus a bad idea if the string's name was long.
Recent improvements by crawshaw have changed that.
Instead of placing long strings behind opaque names
in local packages, place them in the global string
package and make them content-addressable.
Symbol names still occur in the object files,
so use a hash to avoid needless length there.
Alexandru Moșoi [Mon, 14 Mar 2016 18:11:19 +0000 (19:11 +0100)]
cmd/compile: fix no-opt build after moving decomposing user functions
decompose-builtin pass requires an opt pass, but -N disables
late-opt, the only opt pass (out of two) that happens
after decompose-builtin. This CL enables both 'opt' and 'late opt'
passes. The extra compile time for 'late opt' in negligible
since most rewrites were already done in the first 'opt'
(also measured before). We should put some effort in splitting the
generic rules into required and optional.
Also update generic.rules comments about lowering
of StringMake and SliceMake.
Michael Pratt [Sat, 12 Mar 2016 22:07:40 +0000 (14:07 -0800)]
cmd/compile: remove amd64 code from package gc and the core gen tool
Parts of the SSA compiler in package gc contain amd64-specific code,
most notably Prog generation. Move this code into package amd64, so that
other architectures can be added more easily.
In package gc, this change is just moving code. There are no functional
changes or even any larger structural changes beyond changing function
names (mostly for export).
In the cmd/compile/internal/ssa/gen tool, more information is included
in arch to remove the AMD64-specific behavior in the main portion of the
tool. The generated opGen.go is identical.
Change-Id: I8eb37c6e6df6de1b65fa7dab6f3bc32c29daf643
Reviewed-on: https://go-review.googlesource.com/20609 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Austin Clements [Sat, 27 Feb 2016 23:44:25 +0000 (18:44 -0500)]
runtime: document the G states
In particular, write down the rules for stack ownership because the
details of this are about to get very important with concurrent stack
shrinking. (Interestingly, the details don't actually change, but
anything that's currently skating on thin ice is likely to fall
through.)
Fox #12967.
Change-Id: I561e2610e864295e9faba07717a934aabefcaab9
Reviewed-on: https://go-review.googlesource.com/20034 Reviewed-by: Rick Hudson <rlh@golang.org>
Austin Clements [Tue, 16 Feb 2016 17:23:33 +0000 (12:23 -0500)]
runtime: copy stack before adjusting
Currently copystack adjusts pointers in the old stack and then copies
the adjusted stack to the new stack. In addition to being generally
confusing, this is going to make concurrent stack shrinking harder.
Switch this around so that we first copy the stack and then adjust
pointers on the new stack (never writing to the old stack).
This reprises CL 15996, but takes a different and simpler approach. CL
15996 still walked the old stack while adjusting pointers on the new
stack. In this CL, we adjust auxiliary structures before walking the
stack, so we can just walk the new stack.
For #12967.
Change-Id: I94fa86f823ba9ee478e73b2ba509eed3361c43df
Reviewed-on: https://go-review.googlesource.com/20033 Reviewed-by: Rick Hudson <rlh@golang.org>
Todd Neal [Mon, 14 Mar 2016 04:04:31 +0000 (23:04 -0500)]
cmd/compile: change the type of ssa Warnl line number
Line numbers are always int32, so the Warnl function should take the
line number as an int32 as well. This matches gc.Warnl and removes
a cast every place it's used.
The only remaining place that generated ADATA
Prog was the assembler. Stop, and delete some
now-dead code.
Passes toolstash -cmp.
Change-Id: I26578ff1b4868e98562b44f69d909c083e96f8d5
Reviewed-on: https://go-review.googlesource.com/20646 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Instead of generating ADATA instructions for
static data, write that static data directly
into the linker sym.
This is considerably more efficient.
The assembler still generates
ADATA instructions, so the ADATA machinery
cannot be dismantled yet. (Future work.)
Skipping ADATA has a significant impact
compiling the unicode package, which has lots
of static data.
name old time/op new time/op delta
Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30)
name old alloc/op new alloc/op delta
Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30)
name old allocs/op new allocs/op delta
Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30)
This does not pass toolstash -cmp, because
this changes the order in which some relocations
get added, and thus it changes the output from
the compiler. It is not worth the execution time
to sort the relocs in the normal case.
However, compiling with -S -v generates identical
output if (1) you suppress printing of ADATA progs
in flushplist and (2) you suppress printing of
cpu timing. It is reasonable to suppress printing
the ADATA progs, since the data itself is dumped
later. I am therefore fairly confident that all
changes are superficial and non-functional.
Fixes #14786, although there's more to do
in general.
Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82
Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Dominik Honnef [Mon, 14 Mar 2016 00:59:22 +0000 (01:59 +0100)]
reflect: use SelectDir instead of uintptr in runtimeSelect
And fix the wrong comment.
Initially found this because the comment was wrong about the possible
values. Then noticed that there doesn't seem to be any reason to use
uintptr over SelectDir.
Martin Möhrmann [Sun, 13 Mar 2016 17:58:17 +0000 (18:58 +0100)]
runtime: speed up growslice by avoiding divisions
Only compute the number of maximum allowed elements per slice once.
Special case newcap computation for slices with byte sized elements.
name old time/op new time/op delta
GrowSliceBytes-2 61.1ns ± 1% 43.4ns ± 1% -29.00% (p=0.000 n=20+20)
GrowSliceInts-2 85.9ns ± 1% 75.7ns ± 1% -11.80% (p=0.000 n=20+20)
Change-Id: I5d9c0d5987cdd108ac29dc32e31912dcefa2324d
Reviewed-on: https://go-review.googlesource.com/20653 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Brad Fitzpatrick [Sun, 13 Mar 2016 19:40:09 +0000 (12:40 -0700)]
os/user: fix formatting of error group lookup message
It was failing like "unknown groupid ᎈ|" instead of "unknown groupid
5000" due to the conversion from int to string.
Updates #14806
Change-Id: I83e4b478ff628ad4053573a9f32b3fadce22e847
Reviewed-on: https://go-review.googlesource.com/20642 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
cmd/internal/obj: sort relocs by off when printing
This makes the output of compiling with -S more
stable in the face of unimportant variation in the
order in which relocs are generated.
It is also more pleasant to read the relocs when
they are sorted.
Also, do some minor cleanup.
For #14786
Change-Id: Id92020b13fd21777dfb5b29c2722c3b2eb27001b
Reviewed-on: https://go-review.googlesource.com/20641 Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Matthew Dempsky [Fri, 11 Mar 2016 00:15:44 +0000 (16:15 -0800)]
cmd/compile: rework how fieldtrack is implemented
Shrinks gc.Type and gc.Func slightly.
Passes "GOEXPERIMENT=fieldtrack ./all.bash" and "go test -a
-toolexec='toolstash -cmp' -ldflags=-k=rsc.io/tmp/fieldtrack.tracked
rsc.io/tmp/fieldtrack".
Todd Neal [Sat, 12 Mar 2016 01:36:54 +0000 (19:36 -0600)]
cmd/compile: const folding for float32/64
Split the auxFloat type into 32/64 bit versions and perform checking for
exactly representable float32 values. Perform const folding on
float32/64. Comment out some const negation rules that the frontend
already performs.
Alexandru Moșoi [Mon, 7 Mar 2016 17:36:16 +0000 (18:36 +0100)]
cmd/compile/internal/ssa: generalize prove to all booleans
* Refacts a bit saving and restoring parents restrictions
* Shaves ~100k from pkg/tools/linux_amd64,
but most of the savings come from the rewrite rules.
* Improves on the following artificial test case:
func f1(a4 bool, a6 bool) bool {
return a6 || (a6 || (a6 || a4)) || (a6 || (a4 || a6 || (false || a6)))
}
Change-Id: I714000f75a37a3a6617c6e6834c75bd23674215f
Reviewed-on: https://go-review.googlesource.com/20306 Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Emmanuel Odeke [Sat, 27 Feb 2016 10:14:06 +0000 (03:14 -0700)]
net/http: make ParseMultipartForm also populate Request.PostForm
Ensures that after request.ParseMultipartForm has been invoked,
Request.PostForm and Request.Form are both populated with the
same formValues read in, instead of only populating Request.Form.
Alex Brainman [Fri, 11 Mar 2016 01:19:08 +0000 (12:19 +1100)]
cmd/link: rewrite pe symbol table generating code
Every go executable has COFF symbol table appended at the end. The table is
used by nm and addr2line and contains all symbols present in the executable.
The table is quite large. For example, my go.exe has 11736 records.
To generate symbol table:
1) we walk "all symbols" list to count symbols we want for the table;
2) we allocate large global array of COFFSym structs (32 bytes each)
to fit our symbols;
3) we walk "all symbols" list again to fill our array with contents;
4) we iterate over our global array to write all records to the file.
This CL changes all these steps with single step:
- walk "all symbols" list and write each COFF symbol table record to
the file as we go.
I hope new version is faster and uses less garbage, but I don't know
how to benchmark this.
Change-Id: Ie4870583250131ea4428e0e83a0696c9df1794e0
Reviewed-on: https://go-review.googlesource.com/20580 Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
Keith Randall [Sat, 12 Mar 2016 01:39:00 +0000 (17:39 -0800)]
cmd/compile: strength reduce *24
We use *24 a lot for pointer arithmetic when accessing slices
of slices ([][]T). Rewrite to use an LEA and a shift.
The shift will likely be free, as it often gets folded into
an indexed load/store.