Austin Clements [Thu, 18 Jan 2018 22:33:04 +0000 (17:33 -0500)]
runtime: ensure abort actually crashes the process
On all non-x86 arches, runtime.abort simply reads from nil.
Unfortunately, if this happens on a user stack, the signal handler
will dutifully turn this into a panicmem, which lets user defers run
and which user code can even recover from.
To fix this, add an explicit check to the signal handler that turns
faults in abort into hard crashes directly in the signal handler. This
has the added benefit of giving a register dump at the abort point.
Austin Clements [Wed, 17 Jan 2018 20:51:09 +0000 (15:51 -0500)]
runtime: call abort instead of raw INT $3 or bad MOV
Everything except for amd64, amd64p32, and 386 currently defines and
uses an abort function. This CL makes these match. The next CL will
recognize the abort function to make this more useful.
Austin Clements [Fri, 12 Jan 2018 17:39:22 +0000 (12:39 -0500)]
runtime: make throw safer to call
Currently, throw may grow the stack, which means whenever we call it
from a context where it's not safe to grow the stack, we first have to
switch to the system stack. This is pretty easy to get wrong.
Fix this by making throw switch to the system stack so it doesn't grow
the stack and is hence safe to call without a system stack switch at
the call site.
The only thing this complicates is badsystemstack itself, which would
now go into an infinite loop before printing anything (previously it
would also go into an infinite loop, but would at least print the
error first). Fix this by making badsystemstack do a direct write and
then crash hard.
Austin Clements [Thu, 18 Jan 2018 21:36:20 +0000 (16:36 -0500)]
runtime: move unrecoverable panic handling to the system stack
Currently parts of unrecoverable panic handling (notably, printing
panic messages) can happen on the user stack. This may grow the stack,
which is generally fine, but if we're handling a runtime panic, it's
better to do as little as possible in case the runtime is in an
inconsistent state.
Hence, this commit rearranges the handling of unrecoverable panics so
that it's done entirely on the system stack.
This is mostly a matter of shuffling code a bit so everything can move
into a systemstack block. The one slight subtlety is in the "panic
during panic" case, where we now depend on startpanic_m's caller to
print the stack rather than startpanic_m itself. To make this work,
startpanic_m now returns a boolean indicating that the caller should
avoid trying to print any panic messages and get right to the stack
trace. Since the caller is already in a position to do this, this
actually simplifies things a little.
Austin Clements [Thu, 11 Jan 2018 21:32:02 +0000 (16:32 -0500)]
cmd/compile: add fence-post implications to prove
This adds four new deductions to the prove pass, all related to adding
or subtracting one from a value. This is the first hint of actual
arithmetic relations in the prove pass.
The most effective of these is
x-1 >= w && x > min ⇒ x > w
This helps eliminate bounds checks in code like
if x > 0 {
// do something with s[x-1]
}
Altogether, these deductions prove an additional 260 branches in std
and cmd. Furthermore, they will let us eliminate some tricky
compiler-inserted panics in the runtime that are interfering with
static analysis.
Fixes #23354.
Change-Id: I7088223e0e0cd6ff062a75c127eb4bb60e6dce02
Reviewed-on: https://go-review.googlesource.com/87480 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Austin Clements [Wed, 10 Jan 2018 21:28:58 +0000 (16:28 -0500)]
cmd/compile: make prove pass use unsatisfiability
Currently the prove pass uses implication queries. For each block, it
collects the set of branch conditions leading to that block, and
queries this fact table for whether any of these facts imply the
block's own branch condition (or its inverse). This works remarkably
well considering it doesn't do any deduction on these facts, but it
has various downsides:
1. It requires an implementation both of adding facts to the table and
determining implications. These are very nearly duals of each
other, but require separate implementations. Likewise, the process
of asserting facts of dominating branch conditions is very nearly
the dual of the process of querying implied branch conditions.
2. It leads to less effective use of derived facts. For example, the
prove pass currently derives facts about the relations between len
and cap, but can't make use of these unless a branch condition is
in the exact form of a derived fact. If one of these derived facts
contradicts another fact, it won't notice or make use of this.
This CL changes the approach of the prove pass to instead use
*contradiction* instead of implication. Rather than ever querying a
branch condition, it simply adds branch conditions to the fact table.
If this leads to a contradiction (specifically, it makes the fact set
unsatisfiable), that branch is impossible and can be cut. As a result,
1. We can eliminate the code for determining implications
(factsTable.get disappears entirely). Also, there is now a single
implementation of visiting and asserting branch conditions, since
we don't have to flip them around to treat them as facts in one
place and queries in another.
2. Derived facts can be used effectively. It doesn't matter *why* the
fact table is unsatisfiable; a contradiction in any of the facts is
enough.
3. As an added benefit, it's now quite easy to avoid traversing beyond
provably-unreachable blocks. In contrast, the current
implementation always visits all blocks.
The prove pass already has nearly all of the mechanism necessary to
compute unsatisfiability, which means this both simplifies the code
and makes it more powerful.
The only complication is that the current implication procedure has a
hack for dealing with the 0 <= Args[0] condition of OpIsInBounds and
OpIsSliceInBounds. We replace this with asserting the appropriate fact
when we process one of these conditions. This seems much cleaner
anyway, and works because we can now take advantage of derived facts.
This has no measurable effect on compiler performance.
Effectiveness:
There is exactly one condition in all of std and cmd that this fails
to prove that the old implementation could: (int64(^uint(0)>>1) < x)
in encoding/gob. This can never be true because x is an int, and it's
basically coincidence that the old code gets this. (For example, it
fails to prove the similar (x < ^int64(^uint(0)>>1)) condition that
immediately precedes it, and even though the conditions are logically
unrelated, it wouldn't get the second one if it hadn't first processed
the first!)
It does, however, prove a few dozen additional branches. These come
from facts that are added to the fact table about the relations
between len and cap. These were almost never queried directly before,
but could lead to contradictions, which the unsat-based approach is
able to use.
There are exactly two branches in std and cmd that this implementation
proves in the *other* direction. This sounds scary, but is okay
because both occur in already-unreachable blocks, so it doesn't matter
what we chose. Because the fact table logic is sound but incomplete,
it fails to prove that the block isn't reachable, even though it is
able to prove that both outgoing branches are impossible. We could
turn these blocks into BlockExit blocks, but it doesn't seem worth the
trouble of the extra proof effort for something that happens twice in
all of std and cmd.
Tests:
This CL updates test/prove.go to change the expected messages because
it can no longer give a "reason" why it proved or disproved a
condition. It also adds a new test of a branch it couldn't prove
before.
It mostly guts test/sliceopt.go, removing everything related to slice
bounds optimizations and moving a few relevant tests to test/prove.go.
Much of this test is actually unreachable. The new prove pass figures
this out and doesn't try to prove anything about the unreachable
parts. The output on the unreachable parts is already suspect because
anything can be proved at that point, so it's really just a regression
test for an algorithm the compiler no longer uses.
This is a step toward fixing #23354. That issue is quite easy to fix
once we can use derived facts effectively.
Change-Id: Ia48a1b9ee081310579fe474e4a61857424ff8ce8
Reviewed-on: https://go-review.googlesource.com/87478 Reviewed-by: Keith Randall <khr@golang.org>
Austin Clements [Wed, 10 Jan 2018 22:39:43 +0000 (17:39 -0500)]
cmd/compile: simplify limit logic in prove
This replaces the open-coded intersection of limits in the prove pass
with a general limit intersection operation. This should get identical
results except in one case where it's more precise: when handling an
equality relation, if the value is *outside* the existing range, this
will reduce the range to empty rather than resetting it. This will be
important to a follow-up CL where we can take advantage of empty
ranges.
For #23354.
Change-Id: I3d3d75924f61b1da1cb604b3a9d189b26fb3a14e
Reviewed-on: https://go-review.googlesource.com/87477
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Alberto Donizetti [Sun, 14 Jan 2018 18:00:36 +0000 (19:00 +0100)]
math/big: allocate less in Float.Sqrt
The Newton sqrtInverse procedure we use to compute Float.Sqrt should
not allocate a number of times proportional to the number of Newton
iterations we need to reach the desired precision.
At the beginning the function the target precision is known, so even
if we do want to perform the early steps at low precisions (to save
time), it's still possible to pre-allocate larger backing arrays, both
for the temp variables in the loop and the variable that'll hold the
final result.
There's one complication. At the following line:
u.Sub(three, u)
the Sub method will allocate, because the receiver aliases one of the
arguments, and the large backing array we initially allocated for u
will be replaced by a smaller one allocated by Sub. We can work around
this by introducing a second temp variable u2 that we use to hold the
Sub call result.
Overall, the sqrtInverse procedure still allocates a number of times
proportional to the number of Newton steps, because unfortunately a
few of the Mul calls in the Newton function allocate; but at least we
allocate less in the function itself.
Matthew Dempsky [Thu, 8 Mar 2018 09:50:36 +0000 (01:50 -0800)]
cmd/compile: cleanup nodpc and nodfp
Instead of creating a new &nodfp expression for every recover() call,
or a new nodpc variable for every function instrumented by the race
detector, this CL introduces two new uintptr-typed pseudo-variables
callerSP and callerPC. These pseudo-variables act just like calls to
the runtime's getcallersp() and getcallerpc() functions.
For consistency, change runtime.gorecover's builtin stub's parameter
type from "*int32" to "uintptr".
Passes toolstash-check, but toolstash-check -race fails because of
register allocator changes.
Change-Id: I985d644653de2dac8b7b03a28829ad04dfd4f358
Reviewed-on: https://go-review.googlesource.com/99416
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Michael Kasch [Fri, 2 Mar 2018 18:03:21 +0000 (19:03 +0100)]
time: add support for parsing timezones denoted by sign and offset
IANA Zoneinfo does not provide names for all timezones. Some are denoted
by a sign and an offset only. E.g: Europe/Turkey is currently +03 or
America/La_Paz which is -04 (https://data.iana.org/time-zones/releases/tzdata2018c.tar.gz)
erifan01 [Mon, 16 Oct 2017 10:29:02 +0000 (10:29 +0000)]
math/big: optimize addVW and subVW on arm64
The biggest hot spot of the existing implementation is "load" operations, which lead to poor performance.
By unrolling the cycle 4 times and 2 times, and using "LDP", "STP" instructions,
this CL can reduce the "load" cost and improve performance.
When instructions add, and, or, xor, and movd have
constant operands in some cases more instructions are
generated than necessary by the assembler.
This adds more opcode/operand combinations to the optab
and improves the code generation for the cases where the
size and sign of the constant allows the use of 1
instructions instead of 2.
Example of previous code:
oris r3, r0, 0
ori r3, r3, 65533
now:
ori r3, r0, 65533
This does not significantly reduce the overall binary size
because the improvement depends on the constant value.
Some procedures show a 1-2% reduction in size. This improvement
could also be significant in cases where the extra instructions
occur in a critical loop.
Testcase ppc64enc.s was added to cmd/asm/internal/asm/testdata
with the variations affected by this change.
Joe Tsai [Wed, 7 Mar 2018 22:14:19 +0000 (14:14 -0800)]
encoding/csv: avoid mangling invalid UTF-8 in Writer
In the situation where a quoted field is necessary, avoid processing
each UTF-8 rune one-by-one, which causes mangling of invalid sequences
into utf8.RuneError, causing a loss of information.
Instead, search only for the escaped characters, handle those specially
and copy everything else in between verbatim.
This symmetrically matches the behavior of Reader.
Fixes #24298
Change-Id: I9276f64891084ce8487678f663fad711b4095dbb
Reviewed-on: https://go-review.googlesource.com/99297
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
The original code inserts "else{", deletes "else", and then positions
a new block just after the "}" that must come before the "else".
That works on gofmt'ed code, but fails if the code looks like "}else".
When there is no space between the "{" and the "else", the new block
is inserted into a location that we are deleting, leading to the
"overlapping edits" mentioned above.
This CL fixes this case by not deleting the "else" but just using the
one that is already there. That requires adjust the block offset to
come after the "{" that we insert.
Fixes #23927
Change-Id: I40ef592490878765bbce6550ddb439e43ac525b2
Reviewed-on: https://go-review.googlesource.com/98935
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
Ian Lance Taylor [Mon, 26 Feb 2018 22:03:47 +0000 (14:03 -0800)]
runtime: get traceback from VDSO code
Currently if a profiling signal arrives while executing within a VDSO
the profiler will report _ExternalCode, which is needlessly confusing
for a pure Go program. Change the VDSO calling code to record the
caller's PC/SP, so that we can do a traceback from that point. If that
fails for some reason, report _VDSO rather than _ExternalCode, which
should at least point in the right direction.
This adds some instructions to the code that calls the VDSO, but the
slowdown is reasonably negligible:
Ian Lance Taylor [Wed, 7 Mar 2018 04:47:38 +0000 (20:47 -0800)]
runtime: change from rt_sigaction to sigaction
This normalizes the Linux code to act like other targets. The size
argument to the rt_sigaction system call is pushed to a single
function, sysSigaction.
This is intended as a simplification step for CL 93875 for #14327.
Change-Id: I594788e235f0da20e16e8a028e27ac8c883907c4
Reviewed-on: https://go-review.googlesource.com/99077
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Austin Clements <austin@google.com>
Elias Naur [Wed, 7 Mar 2018 17:23:21 +0000 (18:23 +0100)]
runtime/cgo: make sure nil is undefined before defining it
While working on standalone builds of gomobile bindings, I ran into
errors on the form:
gcc_darwin_arm.c:30:31: error: ambiguous expansion of macro 'nil' [-Werror,-Wambiguous-macro]
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS11.2.sdk/usr/include/MacTypes.h:94:15: note: expanding this definition of 'nil'
Fix it by undefining nil before defining it in libcgo.h.
Change-Id: I8e9660a68c6c351e592684d03d529f0d182c0493
Reviewed-on: https://go-review.googlesource.com/99215
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Matthew Dempsky [Fri, 2 Mar 2018 23:20:49 +0000 (15:20 -0800)]
cmd/compile: prevent untyped types from reaching walk
We already require expressions to have already been typechecked before
reaching walk. Moreover, all untyped expressions should have been
converted to their default type by walk.
However, in practice, we've been somewhat sloppy and inconsistent
about ensuring this. In particular, a lot of AST rewrites ended up
leaving untyped bool expressions scattered around. These likely aren't
harmful in practice, but it seems worth cleaning up.
The two most common cases addressed by this CL are:
1) When generating OIF and OFOR nodes, we would often typecheck the
conditional expression, but not apply defaultlit to force it to the
expression's default type.
2) When rewriting string comparisons into more fundamental primitives,
we were simply overwriting r.Type with the desired type, which didn't
propagate the type to nested subexpressions. These are fixed by
utilizing finishcompare, which correctly handles this (and is already
used by other comparison lowering rewrites).
Lastly, walkexpr is extended to assert that it's not called on untyped
expressions.
Fixes #23834.
Change-Id: Icbd29648a293555e4015d3b06a95a24ccbd3f790
Reviewed-on: https://go-review.googlesource.com/98337 Reviewed-by: Robert Griesemer <gri@golang.org>
1. regexps are matched from the start of the disasm line (excluding
line information). This mean that a negative -"memmove" check will
pass against a 'CALL runtime.memmove' line because the line does
not start with 'memmove' (its starts with CALL...).
The way to specify no 'memmove' match whatsoever on the line is
-".*memmove"
2. AFAIK comments on their own line are matched against the first
subsequent non-comment line. So the code above only verifies that
the x := ... line does not generate a memmove. The comment should
be moved near the copy() line, if it's that one we want to not
generate a memmove call.
The fact that the test above is not effective can be checked by
running `go run run.go -v codegen` in the toplevel test directory with
a go1.10 toolchain (that does not have the memmove-elision
optimization). The test will still pass (it shouldn't).
This change changes the regexp to -".*memmove" and moves it near the
line it needs to (not)match.
Tobias Klauser [Wed, 7 Mar 2018 09:20:19 +0000 (10:20 +0100)]
database/sql: fix typo in comment
Change-Id: Ie2966bae1dc2e542c42fb32d8059a4b2d4690014
Reviewed-on: https://go-review.googlesource.com/99115 Reviewed-by: Ian Lance Taylor <iant@golang.org>
jimmyfrasche [Sat, 24 Feb 2018 23:03:58 +0000 (15:03 -0800)]
go/build: correct value of .Doc field
Build could use the package comment from test files to populate the .Doc
field on *Package.
As go list uses this data and several packages in the standard library
have tests with package comments, this lead to:
$ go list -f '{{.Doc}}' flag container/heap image
These examples demonstrate more intricate uses of the flag package.
This example demonstrates an integer heap built using the heap interface.
This example demonstrates decoding a JPEG image and examining its pixels.
This change now only examines non-test files when attempting to populate
.Doc, resulting in the expected behavior:
$ gotip list -f '{{.Doc}}' flag container/heap image
Package flag implements command-line flag parsing.
Package heap provides heap operations for any type that implements heap.Interface.
Package image implements a basic 2-D image library.
Fixes #23594
Change-Id: I37171c26ec5cc573efd273556a05223c6f675968
Reviewed-on: https://go-review.googlesource.com/96976
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Daniel Martí <mvdan@mvdan.cc> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Alex Brainman [Sun, 7 Jan 2018 01:12:25 +0000 (12:12 +1100)]
os: use WIN32_FIND_DATA.Reserved0 to identify symlinks
os.Stat implementation uses instructions described at
https://blogs.msdn.microsoft.com/oldnewthing/20100212-00/?p=14963/
to distinguish symlinks. In particular, it calls
GetFileAttributesEx or FindFirstFile and checks
either WIN32_FILE_ATTRIBUTE_DATA.dwFileAttributes
or WIN32_FIND_DATA.dwFileAttributes to see if
FILE_ATTRIBUTES_REPARSE_POINT flag is set.
And that seems to worked fine so far.
But now we discovered that OneDrive root folder
is determined as directory:
But we did not follow Microsoft's advice to the letter - we never
checked WIN32_FIND_DATA.Reserved0. And adding that extra check
makes Go treat OneDrive as symlink. So use FindFirstFile and
WIN32_FIND_DATA.Reserved0 to determine symlinks.
Matthew Dempsky [Wed, 7 Mar 2018 02:30:58 +0000 (18:30 -0800)]
cmd/compile: remove funcdepth variables
There were only two large classes of use for these variables:
1) Testing "funcdepth != 0" or "funcdepth > 0", which is equivalent to
checking "Curfn != nil".
2) In oldname, detecting whether a closure variable has been created
for the current function, which can be handled by instead testing
"n.Name.Curfn != Curfn".
Lastly, merge funcstart into funchdr, since it's only called once, and
it better matches up with funcbody now.
Matthew Dempsky [Wed, 7 Mar 2018 00:20:10 +0000 (16:20 -0800)]
cmd/compile: cleanup funccompile and compile
Bring these functions next to each other, and clean them up a little
bit. Also, change emitptrargsmap to take Curfn as a parameter instead
of a global.
This CL generalizes this rewrite to also apply for slow map deletes.
This could be extended to apply even more generally to other builtins,
but as discussed on #24259, there are cases where we must *not* do
this (e.g., "defer recover()"). However, if we elect to do this more
generally, this CL should still make that easier.
Lastly, while here, fix a few isues in wrapCall (nee walkprintfunc):
1) lookupN appends the generation number to the symbol anyway, so "%d"
was being literally included in the generated function names.
2) walkstmt will be called when the function is compiled later anyway,
so no need to do it now.
Alberto Donizetti [Tue, 6 Mar 2018 08:39:14 +0000 (09:39 +0100)]
test/codegen: port math/bits.TrailingZeros tests to codegen
And remove them from ssa_test.
Change-Id: Ib5de5c0d908f23915e0847eca338cacf2fa5325b
Reviewed-on: https://go-review.googlesource.com/98795 Reviewed-by: Giovanni Bajo <rasky@develer.com>
Rob Pike [Mon, 5 Mar 2018 05:21:44 +0000 (16:21 +1100)]
cmd/doc: make local dot-slash path names work
Before, an argument that started ./ or ../ was not treated as
a package relative to the current directory. Thus
$ cd $GOROOT/src/text
$ go doc ./template
could find html/template as $GOROOT/src/html/./template
is a valid Go source directory.
Fix this by catching such paths and making them absolute before
processing.
Fixes #23383.
Change-Id: Ic2a92eaa3a6328f728635657f9de72ac3ee82afb
Reviewed-on: https://go-review.googlesource.com/98396 Reviewed-by: Ian Lance Taylor <iant@golang.org>
The biggest hot spot of the existing implementation is "load" operations, which lead to poor performance.
By unrolling the cycle 4x and 2x, and using "LDP", "STP" instructions, this CL can reduce the "load" cost and improve performance.
Andrey Mirtchovski [Mon, 5 Mar 2018 20:04:25 +0000 (20:04 +0000)]
os/signal: disable loading of history during test
This change modifies Go to disable loading of users' shell history for
TestTerminalSignal tests. TestTerminalSignal, as part of its workload,
will execute a new interactive bash shell. Bash will attempt to load the
user's history from the file pointed to by the HISTFILE environment
variable. For users with large histories that may take up to several
seconds, pushing the whole test past the 5 second timeout and causing
it to fail.
Ian Lance Taylor [Mon, 5 Mar 2018 06:10:04 +0000 (22:10 -0800)]
runtime: rename vdso symbols to use camel case
This was originally C code using names with underscores, which were
retained when the code was rewritten into Go. Change the code to use
Go-like camel case names.
The names that come from the ELF ABI are left unchanged.
Alberto Donizetti [Fri, 2 Mar 2018 14:16:27 +0000 (15:16 +0100)]
test: port bits.Len intrinsics tests to the new codegen harness
This change move bits.Len* intrinsification tests to the new codegen
test harness, removing them from the old ssa_test file. Five different
test functions (one for each bit.Len function tested) was used, to
avoid possible unwanted interactions between multiple calls inside one
function.
Change-Id: Iffd5be55b58e88597fa30a562a28dacb01236d8b
Reviewed-on: https://go-review.googlesource.com/98156
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Giovanni Bajo <rasky@develer.com>
Giovanni Bajo [Sat, 3 Mar 2018 15:00:43 +0000 (16:00 +0100)]
test: move load/store combines into asmcheck
This CL moves the load/store combining tests into asmcheck.
In addition at being more compact, it's also now easier to
spot what it is missing in each architecture.
While doing so, I think I uncovered a bug in ppc64le and arm64
rules, because they fail to load/store combine in non-trivial
functions. Not sure why, I'll open an issue.
Change-Id: Ia1572d53c0553d9104f3e52b95e4d1768a8440a3
Reviewed-on: https://go-review.googlesource.com/98441
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Giovanni Bajo [Sat, 3 Mar 2018 18:44:47 +0000 (19:44 +0100)]
test: in asmcheck, dump only the functions which fail
Before this change, in case of any failure, asmcheck was
dumping to stderr the whole output of compile -S, which
can be very long if it contains multiple functions.
Make it so it filters the output to only display the
assembly output of functions for which at least one opcode
check failed. This greatly simplifies debugging.
Change-Id: I1bbf54473b8252a3384e2c1dade82d926afc119d
Reviewed-on: https://go-review.googlesource.com/98444
Run-TryBot: Giovanni Bajo <rasky@develer.com> Reviewed-by: Keith Randall <khr@golang.org>
Giovanni Bajo [Sat, 3 Mar 2018 13:47:20 +0000 (14:47 +0100)]
test: use the version of Go used to run run.go
Currently, the top-level testsuite always uses whatever version
of Go is found in the PATH to execute all the tests. This
forces the developers to tweak the PATH to run the testsuite.
Change it to use the same version of Go used to run run.go.
This allows developers to run the testsuite using the tip
compiler by simply saying "../bin/go run run.go".
I think this is a better solution compared to always forcing
"../bin/go", because it allows developers to run the testsuite
using different Go versions, for instance to check if a new
test is fixed in tip compared to the installed compiler.
Fixes #24217
Change-Id: I41b299c753b6e77c41e28be9091b2b630efea9d2
Reviewed-on: https://go-review.googlesource.com/98439
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Tobias Klauser [Fri, 2 Mar 2018 10:27:15 +0000 (11:27 +0100)]
runtime: use vDSO for clock_gettime on linux/arm
Use the __vdso_clock_gettime fast path via the vDSO on linux/arm to
speed up nanotime and walltime. This results in the following
performance improvement for time.Now on a RaspberryPi 3 (running
32bit Raspbian, i.e. GOOS=linux/GOARCH=arm):
name old time/op new time/op delta
TimeNow 0.99µs ± 0% 0.39µs ± 1% -60.74% (p=0.000 n=12+20)
Change-Id: I3598278a6c88d7f6a6ce66c56b9d25f9dd2f4c9a
Reviewed-on: https://go-review.googlesource.com/98095 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Joe Tsai [Fri, 10 Nov 2017 01:33:12 +0000 (17:33 -0800)]
encoding/json: use sync.Map for field cache
The previous type cache is quadratic in time in the situation where
new types are continually encountered. Now that it is possible to dynamically
create new types with the reflect package, this can cause json to
perform very poorly.
Switch to sync.Map which does well when the cache has hit steady state,
but also handles occasional updates in better than quadratic time.
Keith Randall [Fri, 2 Mar 2018 00:38:41 +0000 (16:38 -0800)]
internal/bytealg: move IndexByte asssembly to the new bytealg package
Move the IndexByte function from the runtime to a new bytealg package.
The new package will eventually hold all the optimized assembly for
groveling through byte slices and strings. It seems a better home for
this code than randomly keeping it in runtime.
Once this is in, the next step is to move the other functions
(Compare, Equal, ...).
Update #19792
This change seems complicated enough that we might just declare
"not worth it" and abandon. Opinions welcome.
The core assembly is all unchanged, except minor modifications where
the code reads cpu feature bits.
The wrapper functions have been cleaned up as they are now actually
checked by vet.
Brad Fitzpatrick [Tue, 27 Feb 2018 17:23:14 +0000 (17:23 +0000)]
net: skip flaky TestLookupLongTXT for now
Flaky tests failing trybots help nobody.
Updates #22857
Change-Id: I87bc018651ab4fe02560a6d24c08a1d7ccd8ba37
Reviewed-on: https://go-review.googlesource.com/97416 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Hana Kim [Thu, 22 Feb 2018 18:27:39 +0000 (13:27 -0500)]
internal/trace: remove backlinks from span/task end to start
Even though undocumented, the assumption is the Event's link field
points to the following event in the future. The new span/task event
processing breaks the assumption.