Implements detection of x86 cpu features that
are used in the go standard library.
Changes all standard library packages to use the new cpu package
instead of using runtime internal variables to check x86 cpu features.
Updates: #15403
Change-Id: I2999a10cb4d9ec4863ffbed72f4e021a1dbc4bb9
Reviewed-on: https://go-review.googlesource.com/41476
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Eliminates stores of values that have just been loaded from the same
location. Handles the common case where there are up to 3 intermediate
stores to non-overlapping struct fields.
For example the loads and stores of x.a, x.b and x.d in the following
function are now removed:
type T struct {
a, b, c, d int
}
func f(x *T) {
y := *x
y.c += 8
*x = y
}
Before this CL (s390x):
TEXT "".f(SB)
MOVD "".x(R15), R5
MOVD (R5), R1
MOVD 8(R5), R2
MOVD 16(R5), R0
MOVD 24(R5), R4
ADD $8, R0, R3
STMG R1, R4, (R5)
RET
After this CL (s390x):
TEXT "".f(SB)
MOVD "".x(R15), R1
MOVD 16(R1), R0
ADD $8, R0, R0
MOVD R0, 16(R1)
RET
In total these rules are triggered ~5091 times during all.bash,
which is broken down as:
Intermediate stores | Triggered
--------------------+----------
0 | 1434
1 | 2508
2 | 888
3 | 261
--------------------+----------
Change-Id: Ia4721ae40146aceec1fdd3e65b0e9283770bfba5
Reviewed-on: https://go-review.googlesource.com/38793
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The files PPC64.rules and rewritePPC64.go were out of sync due to
conflicts between CL 41630 and CL 42145 (i.e. running 'go run *.go'
in the gen directory resulted in unexpected changes).
Change-Id: I1d409656b66afeab6cb9c6df9b3dcab7859caa75
Reviewed-on: https://go-review.googlesource.com/43091
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
This can make life easier for Delve (and other debuggers),
and can help them with bug reports.
Sample producer field (from objdump):
<48> DW_AT_producer : Go cmd/compile devel +8a59dbf41a Mon May 8 16:02:44 2017 -0400
Change-Id: I0605843c959b53a60a25a3b870aa8755bf5d5b13
Reviewed-on: https://go-review.googlesource.com/33588
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We do a division by the elem type size to check if the array size would
be too large for the virtual address space. This is a silly check if the
size is 0, but the problem is that it means a division by zero and a
panic.
Since arrays of empty structs are valid in a regular program, make them
also work in reflect.
Use a separate, explicit test with struct{}{} to make sure the test for
a zero-sized type is not confused with the rest.
Fixes#20313.
Change-Id: I47b8b87e6541631280b79227bdea6a0f6035c9e0
Reviewed-on: https://go-review.googlesource.com/43131
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This adds math/bits intrinsics for OnesCount, Len, TrailingZeros on
ppc64x.
benchmark old ns/op new ns/op delta
BenchmarkLeadingZeros-16 4.26 1.71 -59.86%
BenchmarkLeadingZeros16-16 3.04 1.83 -39.80%
BenchmarkLeadingZeros32-16 3.31 1.82 -45.02%
BenchmarkLeadingZeros64-16 3.69 1.71 -53.66%
BenchmarkTrailingZeros-16 2.55 1.62 -36.47%
BenchmarkTrailingZeros32-16 2.55 1.77 -30.59%
BenchmarkTrailingZeros64-16 2.78 1.62 -41.73%
BenchmarkOnesCount-16 3.19 0.93 -70.85%
BenchmarkOnesCount32-16 2.55 1.18 -53.73%
BenchmarkOnesCount64-16 3.22 0.93 -71.12%
Update #18616
I also made a change to bits_test.go because when debugging some failures
the output was not quite providing the right argument information.
Change-Id: Ia58d31d1777cf4582a4505f85b11a1202ca07d3e
Reviewed-on: https://go-review.googlesource.com/41630
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: Keith Randall <khr@golang.org>
When constructing a new type for an array type in ArrayOf, we don't
reset tflag to 0. All the other methods in the package, such as SliceOf,
do this already. This results in the new array type having weird issues
when being printed, such as having tflagExtraStar set when it shouldn't.
That flag removes the first char to get rid of '*', but when used
incorrectly in this case it eats the '[' character leading to broken
strings like "3]int".
This was fixed in 56752eb2 for issue #16722, but ArrayOf was missed.
Also make the XM test struct have a non-zero size as that leads to a
division by zero panic in ArrayOf.
Fixes#20311.
Change-Id: I18f1027fdbe9f71767201e7424269c3ceeb23eb5
Reviewed-on: https://go-review.googlesource.com/43130
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also change type from map[*types.Type]bool to map[*types.Type]struct{}.
This is basically a clean-up.
Change-Id: I167583eff0fa1070a7522647219476033b52b840
Reviewed-on: https://go-review.googlesource.com/41859
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
OpVarXXX Values don't generate instructions,
so there's no reason not to duplicate them,
and duplicating them generates better code
(fewer branches).
This requires changing the start/end accounting
to correctly handle the case in which we have run
of Values beginning with an OpVarXXX, e.g.
OpVarDef, OpZeroWB, OpMoveWB.
In that case, the sequence of values should begin
at the OpZeroWB, not the OpVarDef.
This also lays the groundwork for experimenting
with allowing duplication of some scalar stores.
Shrinks function text sizes a tiny amount:
name old object-bytes new object-bytes delta
Template 381k ± 0% 381k ± 0% -0.01% (p=0.008 n=5+5)
Unicode 203k ± 0% 203k ± 0% -0.04% (p=0.008 n=5+5)
GoTypes 1.17M ± 0% 1.17M ± 0% -0.01% (p=0.008 n=5+5)
SSA 8.24M ± 0% 8.24M ± 0% -0.00% (p=0.008 n=5+5)
Flate 230k ± 0% 230k ± 0% ~ (all equal)
GoParser 286k ± 0% 286k ± 0% ~ (all equal)
Reflect 1.00M ± 0% 1.00M ± 0% ~ (all equal)
Tar 189k ± 0% 189k ± 0% ~ (all equal)
XML 415k ± 0% 415k ± 0% -0.01% (p=0.008 n=5+5)
Updates #19838
Change-Id: Ic5ef30855919f1468066eba08ae5c4bd9a01db27
Reviewed-on: https://go-review.googlesource.com/42011
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
In PPC64 ELF files, the st_other field indicates the number of
prologue instructions between the global and local entry points.
We add the instructions in the compiler and assembler if -shared is used.
We were assuming that the instructions were present when building a
c-archive or PIE or doing dynamic linking, on the assumption that those
are the cases where the go tool would be building with -shared.
That assumption fails when using some other tool, such as Bazel,
that does not necessarily use -shared in exactly the same way.
This CL records in the object file whether a symbol was compiled
with -shared (this will be the same for all symbols in a given compilation)
and uses that information when setting the st_other field.
Fixes#20290.
Change-Id: Ib2b77e16aef38824871102e3c244fcf04a86c6ea
Reviewed-on: https://go-review.googlesource.com/43051
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
When package ssa was created, Type was in package gc.
To avoid circular dependencies, we used an interface (ssa.Type)
to represent type information in SSA.
In the Go 1.9 cycle, gri extricated the Type type from package gc.
As a result, we can now use it in package ssa.
Now, instead of package types depending on package ssa,
it is the other way.
This is a more sensible dependency tree,
and helps compiler performance a bit.
Though this is a big CL, most of the changes are
mechanical and uninteresting.
Interesting bits:
* Add new singleton globals to package types for the special
SSA types Memory, Void, Invalid, Flags, and Int128.
* Add two new Types, TSSA for the special types,
and TTUPLE, for SSA tuple types.
ssa.MakeTuple is now types.NewTuple.
* Move type comparison result constants CMPlt, CMPeq, and CMPgt
to package types.
* We had picked the name "types" in our rules for the handy
list of types provided by ssa.Config. That conflicted with
the types package name, so change it to "typ".
* Update the type comparison routine to handle tuples and special
types inline.
* Teach gc/fmt.go how to print special types.
* We can now eliminate ElemTypes in favor of just Elem,
and probably also some other duplicated Type methods
designed to return ssa.Type instead of *types.Type.
* The ssa tests were using their own dummy types,
and they were not particularly careful about types in general.
Of necessity, this CL switches them to use *types.Type;
it does not make them more type-accurate.
Unfortunately, using types.Type means initializing a bit
of the types universe.
This is prime for refactoring and improvement.
This shrinks ssa.Value; it now fits in a smaller size class
on 64 bit systems. This doesn't have a giant impact,
though, since most Values are preallocated in a chunk.
name old alloc/op new alloc/op delta
Template 37.9MB ± 0% 37.7MB ± 0% -0.57% (p=0.000 n=10+8)
Unicode 28.9MB ± 0% 28.7MB ± 0% -0.52% (p=0.000 n=10+10)
GoTypes 110MB ± 0% 109MB ± 0% -0.88% (p=0.000 n=10+10)
Flate 24.7MB ± 0% 24.6MB ± 0% -0.66% (p=0.000 n=10+10)
GoParser 31.1MB ± 0% 30.9MB ± 0% -0.61% (p=0.000 n=10+9)
Reflect 73.9MB ± 0% 73.4MB ± 0% -0.62% (p=0.000 n=10+8)
Tar 25.8MB ± 0% 25.6MB ± 0% -0.77% (p=0.000 n=9+10)
XML 41.2MB ± 0% 40.9MB ± 0% -0.80% (p=0.000 n=10+10)
[Geo mean] 40.5MB 40.3MB -0.68%
name old allocs/op new allocs/op delta
Template 385k ± 0% 386k ± 0% ~ (p=0.356 n=10+9)
Unicode 343k ± 1% 344k ± 0% ~ (p=0.481 n=10+10)
GoTypes 1.16M ± 0% 1.16M ± 0% -0.16% (p=0.004 n=10+10)
Flate 238k ± 1% 238k ± 1% ~ (p=0.853 n=10+10)
GoParser 320k ± 0% 320k ± 0% ~ (p=0.720 n=10+9)
Reflect 957k ± 0% 957k ± 0% ~ (p=0.460 n=10+8)
Tar 252k ± 0% 252k ± 0% ~ (p=0.133 n=9+10)
XML 400k ± 0% 400k ± 0% ~ (p=0.796 n=10+10)
[Geo mean] 428k 428k -0.01%
Removing all the interface calls helps non-trivially with CPU, though.
name old time/op new time/op delta
Template 178ms ± 4% 173ms ± 3% -2.90% (p=0.000 n=94+96)
Unicode 85.0ms ± 4% 83.9ms ± 4% -1.23% (p=0.000 n=96+96)
GoTypes 543ms ± 3% 528ms ± 3% -2.73% (p=0.000 n=98+96)
Flate 116ms ± 3% 113ms ± 4% -2.34% (p=0.000 n=96+99)
GoParser 144ms ± 3% 140ms ± 4% -2.80% (p=0.000 n=99+97)
Reflect 344ms ± 3% 334ms ± 4% -3.02% (p=0.000 n=100+99)
Tar 106ms ± 5% 103ms ± 4% -3.30% (p=0.000 n=98+94)
XML 198ms ± 5% 192ms ± 4% -2.88% (p=0.000 n=92+95)
[Geo mean] 178ms 173ms -2.65%
name old user-time/op new user-time/op delta
Template 229ms ± 5% 224ms ± 5% -2.36% (p=0.000 n=95+99)
Unicode 107ms ± 6% 106ms ± 5% -1.13% (p=0.001 n=93+95)
GoTypes 696ms ± 4% 679ms ± 4% -2.45% (p=0.000 n=97+99)
Flate 137ms ± 4% 134ms ± 5% -2.66% (p=0.000 n=99+96)
GoParser 176ms ± 5% 172ms ± 8% -2.27% (p=0.000 n=98+100)
Reflect 430ms ± 6% 411ms ± 5% -4.46% (p=0.000 n=100+92)
Tar 128ms ±13% 123ms ±13% -4.21% (p=0.000 n=100+100)
XML 239ms ± 6% 233ms ± 6% -2.50% (p=0.000 n=95+97)
[Geo mean] 220ms 213ms -2.76%
Change-Id: I15c7d6268347f8358e75066dfdbd77db24e8d0c1
Reviewed-on: https://go-review.googlesource.com/42145
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
These collectively fire a few hundred times during make.bash,
mostly rewriting XOR SETNE -> SETEQ.
Fixes#17905.
Change-Id: Ic5eb241ee93ed67099da3de11f59e4df9fab64a3
Reviewed-on: https://go-review.googlesource.com/42491
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
CL 39915 introduced sorting of signats by ShortString
for reproducible builds. But ShortString treats types
byte and uint8 identically; same for rune and uint32.
CL 39915 attempted to compensate for this by only
adding the underlying type (uint8) to signats in addsignat.
This only works for byte and uint8. For e.g. *byte and *uint,
both get added, and their sort order is random,
leading to non-reproducible builds.
One fix would be to add yet another type printing mode
that doesn't eliminate byte and rune, and use it
for sorting signats. But the formatting routines
are complicated enough as it is.
Instead, just sort first by ShortString and then by String.
We can't just use String, because ShortString makes distinctions
that String doesn't. ShortString is really preferred here;
String is serving only as a backstop for handling of bytes and runes.
The long series of types in the test helps increase the odds of
failure, allowing a smaller number of iterations in the test.
On my machine, a full test takes 700ms.
Passes toolstash-check.
Updates #19961Fixes#20272
name old alloc/op new alloc/op delta
Template 37.9MB ± 0% 37.9MB ± 0% +0.12% (p=0.032 n=5+5)
Unicode 28.9MB ± 0% 28.9MB ± 0% ~ (p=0.841 n=5+5)
GoTypes 110MB ± 0% 110MB ± 0% ~ (p=0.841 n=5+5)
Compiler 463MB ± 0% 463MB ± 0% ~ (p=0.056 n=5+5)
SSA 1.11GB ± 0% 1.11GB ± 0% +0.02% (p=0.016 n=5+5)
Flate 24.7MB ± 0% 24.8MB ± 0% +0.14% (p=0.032 n=5+5)
GoParser 31.1MB ± 0% 31.1MB ± 0% ~ (p=0.421 n=5+5)
Reflect 73.9MB ± 0% 73.9MB ± 0% ~ (p=1.000 n=5+5)
Tar 25.8MB ± 0% 25.8MB ± 0% +0.15% (p=0.016 n=5+5)
XML 41.2MB ± 0% 41.2MB ± 0% ~ (p=0.310 n=5+5)
[Geo mean] 72.0MB 72.0MB +0.07%
name old allocs/op new allocs/op delta
Template 384k ± 0% 385k ± 1% ~ (p=0.056 n=5+5)
Unicode 343k ± 0% 344k ± 0% ~ (p=0.548 n=5+5)
GoTypes 1.16M ± 0% 1.16M ± 0% ~ (p=0.421 n=5+5)
Compiler 4.43M ± 0% 4.44M ± 0% +0.26% (p=0.032 n=5+5)
SSA 9.86M ± 0% 9.87M ± 0% +0.10% (p=0.032 n=5+5)
Flate 237k ± 1% 238k ± 0% +0.49% (p=0.032 n=5+5)
GoParser 319k ± 1% 320k ± 1% ~ (p=0.151 n=5+5)
Reflect 957k ± 0% 957k ± 0% ~ (p=1.000 n=5+5)
Tar 251k ± 0% 252k ± 1% +0.49% (p=0.016 n=5+5)
XML 399k ± 0% 401k ± 1% ~ (p=0.310 n=5+5)
[Geo mean] 739k 741k +0.26%
Change-Id: Ic27995a8d374d012b8aca14546b1df9d28d30df7
Reviewed-on: https://go-review.googlesource.com/42955
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
If there were more unused imports than
the maximum default number of errors to report,
the set of reported imports was non-deterministic.
Fix by accumulating and sorting them prior to output.
Fixes#20298
Change-Id: Ib3d5a15fd7dc40009523fcdc1b93ddc62a1b05f2
Reviewed-on: https://go-review.googlesource.com/42954
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
ARM64 assembler backend only accepts loads and stores with small
or aligned offset. The compiler therefore can only fold small or
aligned offsets into loads and stores. For locals and args, their
offsets to SP are not known until very late, and the compiler
makes conservative decision not folding some of them. However,
in most cases, the offset is indeed small or aligned, and can
be folded into load and store (but actually not).
This CL adds support of loads and stores with large and unaligned
offsets. When the offset doesn't fit into the instruction, it
uses two instructions and (for very large offset) the constant
pool. This way, the compiler doesn't need to be conservative,
and can simply fold the offset.
To make it work, the assembler's optab matching rules need to be
changed. Before, MOVD accepts C_UAUTO32K which matches multiple
of 8 between 0 and 32K, and also C_UAUTO16K, which may not be
multiple of 8 and does not fit into MOVD instruction. The
assembler errors in the latter case. This change makes it only
matches multiple of 8 (or offsets within ±256, which also fits
in instruction), and uses the large-or-unaligned-offset rule
for things doesn't fit (without error). Other sized move rules
are changed similarly.
Class C_UAUTO64K and C_UOREG64K are removed, as they are never
used.
In shared library, load/store of global is rewritten to using
GOT and temp register, which conflicts with the use of temp
register for assembling large offset. So the folding is disabled
for globals in shared library mode.
Reduce cmd/go binary size by 2%.
name old time/op new time/op delta
BinaryTree17-8 8.67s ± 0% 8.61s ± 0% -0.60% (p=0.000 n=9+10)
Fannkuch11-8 6.24s ± 0% 6.19s ± 0% -0.83% (p=0.000 n=10+9)
FmtFprintfEmpty-8 116ns ± 0% 116ns ± 0% ~ (all equal)
FmtFprintfString-8 196ns ± 0% 192ns ± 0% -1.89% (p=0.000 n=10+10)
FmtFprintfInt-8 199ns ± 0% 198ns ± 0% -0.35% (p=0.001 n=9+10)
FmtFprintfIntInt-8 294ns ± 0% 293ns ± 0% -0.34% (p=0.000 n=8+8)
FmtFprintfPrefixedInt-8 318ns ± 1% 318ns ± 1% ~ (p=1.000 n=10+10)
FmtFprintfFloat-8 537ns ± 0% 531ns ± 0% -1.17% (p=0.000 n=9+10)
FmtManyArgs-8 1.19µs ± 1% 1.18µs ± 1% -1.41% (p=0.001 n=10+10)
GobDecode-8 17.2ms ± 1% 17.3ms ± 2% ~ (p=0.165 n=10+10)
GobEncode-8 14.7ms ± 1% 14.7ms ± 2% ~ (p=0.631 n=10+10)
Gzip-8 837ms ± 0% 836ms ± 0% -0.14% (p=0.006 n=9+10)
Gunzip-8 141ms ± 0% 139ms ± 0% -1.24% (p=0.000 n=9+10)
HTTPClientServer-8 256µs ± 1% 253µs ± 1% -1.35% (p=0.000 n=10+10)
JSONEncode-8 40.1ms ± 1% 41.3ms ± 1% +3.06% (p=0.000 n=10+9)
JSONDecode-8 157ms ± 1% 156ms ± 1% -0.83% (p=0.001 n=9+8)
Mandelbrot200-8 8.94ms ± 0% 8.94ms ± 0% +0.02% (p=0.000 n=9+9)
GoParse-8 8.69ms ± 0% 8.54ms ± 1% -1.69% (p=0.000 n=8+10)
RegexpMatchEasy0_32-8 227ns ± 1% 228ns ± 1% +0.48% (p=0.016 n=10+9)
RegexpMatchEasy0_1K-8 1.92µs ± 0% 1.63µs ± 0% -15.08% (p=0.000 n=10+9)
RegexpMatchEasy1_32-8 256ns ± 0% 251ns ± 0% -2.19% (p=0.000 n=10+9)
RegexpMatchEasy1_1K-8 2.38µs ± 0% 2.09µs ± 0% -12.49% (p=0.000 n=10+9)
RegexpMatchMedium_32-8 352ns ± 0% 354ns ± 0% +0.39% (p=0.002 n=10+9)
RegexpMatchMedium_1K-8 106µs ± 0% 106µs ± 0% -0.05% (p=0.005 n=10+9)
RegexpMatchHard_32-8 5.92µs ± 0% 5.89µs ± 0% -0.40% (p=0.000 n=9+8)
RegexpMatchHard_1K-8 180µs ± 0% 179µs ± 0% -0.14% (p=0.000 n=10+9)
Revcomp-8 1.20s ± 0% 1.13s ± 0% -6.29% (p=0.000 n=9+8)
Template-8 159ms ± 1% 154ms ± 1% -3.14% (p=0.000 n=9+10)
TimeParse-8 800ns ± 3% 769ns ± 1% -3.91% (p=0.000 n=10+10)
TimeFormat-8 826ns ± 2% 817ns ± 2% -1.04% (p=0.050 n=10+10)
[Geo mean] 145µs 143µs -1.79%
Change-Id: I5fc42087cee9b54ea414f8ef6d6d020b80eb5985
Reviewed-on: https://go-review.googlesource.com/42172
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
It can be disabled by setting the environment variable
GO19CONCURRENTCOMPILATION=0, or with -gcflags=-c=1.
Fixes#15756.
Change-Id: I7acbf16330512b62ee14ecbab1f46b53ec5a67b6
Reviewed-on: https://go-review.googlesource.com/41820
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
A pointer type of underlying type unsafe.Pointer can be used in
unsafe conversions. Document unfortunate status quo.
Fixes#19306.
Change-Id: I28172508a200561f8df366bbf2c2807ef3b48c97
Reviewed-on: https://go-review.googlesource.com/42132
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TestGoroutineCounts currently depends on timing to get 100 goroutines
to a known blocking point before taking a profile. This fails
frequently, with different goroutines captured at different stacks.
The test is disabled on openbsd because it was too flaky, but in fact
it flakes on all platforms.
Fix this by using Gosched instead of timing. This is both much more
reliable and makes the test run faster.
Fixes#15156.
Change-Id: Ia6e894196d717655b8fb4ee96df53f6cc8bc5f1f
Reviewed-on: https://go-review.googlesource.com/42953
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This permits the user to override the code generation flag when they
know better. This is always a good policy for all flags automatically
inserted by the build system.
Doing this now so that I can write a test for #20290.
Update #20290
Change-Id: I5c6708a277238d571b8d037993a5a59e2a442e98
Reviewed-on: https://go-review.googlesource.com/42952
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Issue #15228 describes that reserved address blocks should be used for
documentation purposes. This change updates the prefix length so the
IPv4 address adheres to this.
Change-Id: I237d9cce1a71f4fd95f927ec894ce53fa806047f
Reviewed-on: https://go-review.googlesource.com/42991
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Further examples to support the net package.
See issue #5757
Change-Id: I839fd97a468c8d9195e8f4a0ee886ba50ca3f382
Reviewed-on: https://go-review.googlesource.com/42912
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
As necessary, math functions were structured to use stubs, so that they can
be accelerated with assembly on any platform.
Technique used was minimax polynomial approximation using tables of
polynomial coefficients, with argument range reduction.
Benchmark New Old Speedup
BenchmarkAcos 12.2 47.5 3.89
BenchmarkAcosh 18.5 56.2 3.04
BenchmarkAsin 13.1 40.6 3.10
BenchmarkAsinh 19.4 62.8 3.24
BenchmarkAtan 10.1 23 2.28
BenchmarkAtanh 19.1 53.2 2.79
BenchmarkAtan2 16.5 33.9 2.05
BenchmarkCbrt 14.8 58 3.92
BenchmarkErf 10.8 20.1 1.86
BenchmarkErfc 11.2 23.5 2.10
BenchmarkExp 8.77 53.8 6.13
BenchmarkExpm1 10.1 38.3 3.79
BenchmarkLog 13.1 40.1 3.06
BenchmarkLog1p 12.7 38.3 3.02
BenchmarkPowInt 31.7 40.5 1.28
BenchmarkPowFrac 33.1 141 4.26
BenchmarkTan 11.5 30 2.61
Accuracy was tested against a high precision
reference function to determine maximum error.
Note: ulperr is error in "units in the last place"
max
ulperr
Acos 1.15
Acosh 1.07
Asin 2.22
Asinh 1.72
Atan 1.41
Atanh 3.00
Atan2 1.45
Cbrt 1.18
Erf 1.29
Erfc 4.82
Exp 1.00
Expm1 2.26
Log 0.94
Log1p 2.39
Tan 3.14
Pow will have 99.99% correctly rounded results with reasonable inputs
producing numeric (non Inf or NaN) results
Change-Id: I850e8cf7b70426e8b54ec49d74acd4cddc8c6cb2
Reviewed-on: https://go-review.googlesource.com/38585
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The test "TestTryGrowByResliceInlined" introduced in c08ac36 broke the
noopt builder as it fails when inlining is disabled.
Since there are currently no other options at hand for checking
inlined-ness other than looking at emited symbols of the compilation,
we for now skip the problem causing test by default and only run
it on one specific builder ("linux-amd64").
Also see CL 42813, which introduced the test and contains comments
suggesting this temporary solution.
Change-Id: I3978ab0831da04876cf873d78959f821c459282b
Reviewed-on: https://go-review.googlesource.com/42820
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also switch "stating" to "statting" to describe applying os.Stat to
a resource; the former is more confusable than the latter.
Change-Id: I9d8e3506bd383f8f1479c05948c03b8c633dc4af
Reviewed-on: https://go-review.googlesource.com/42855
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
In the common case, the grow method only needs to reslice the internal
buffer. Making another function call to grow can be expensive when Write
is called very often with small pieces of data (like a byte or rune).
Thus, we add a tryGrowByReslice method that is inlineable so that we can
avoid an extra call in most cases.
name old time/op new time/op delta
WriteByte-4 35.5µs ± 0% 17.4µs ± 1% -51.03% (p=0.000 n=19+20)
WriteRune-4 55.7µs ± 1% 38.7µs ± 1% -30.56% (p=0.000 n=18+19)
BufferNotEmptyWriteRead-4 304µs ± 5% 283µs ± 3% -6.86% (p=0.000 n=19+17)
BufferFullSmallReads-4 87.0µs ± 5% 66.8µs ± 2% -23.26% (p=0.000 n=17+17)
name old speed new speed delta
WriteByte-4 115MB/s ± 0% 235MB/s ± 1% +104.19% (p=0.000 n=19+20)
WriteRune-4 221MB/s ± 1% 318MB/s ± 1% +44.01% (p=0.000 n=18+19)
Fixes#17857
Change-Id: I08dfb10a1c7e001817729dbfcc951bda12fe8814
Reviewed-on: https://go-review.googlesource.com/42813
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
MOVSD is properly handled but its encoding test wasn't enabled. Enable
it.
For reference this was found with a little tool I wrote [1] to explore
which instructions are missing or not tested in the go obj package and
assembler:
"which SSE2 instructions aren't tested? And don't list instructions
which can take MMX operands"
$ x86db-gogen list --extension SSE2 --not-tested --not-mmx
CLFLUSH mem [m: np 0f ae /7] WILLAMETTE,SSE2
MOVSD xmmreg,xmmreg [rm: f2 0f 10 /r] WILLAMETTE,SSE2
MOVSD xmmreg,xmmreg [mr: f2 0f 11 /r] WILLAMETTE,SSE2
MOVSD mem64,xmmreg [mr: f2 0f 11 /r] WILLAMETTE,SSE2
MOVSD xmmreg,mem64 [rm: f2 0f 10 /r] WILLAMETTE,SSE2
(CLFLUSH was introduced with SSE2, but has its own CPUID bit)
[1] https://github.com/dlespiau/x86db
Change-Id: Ic3af3028cb8d4f02e53fdebb9b30fb311f4ee454
Reviewed-on: https://go-review.googlesource.com/42814
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently windows Stat uses combination of Lstat and Readlink to
walk symlinks until it reaches file or directory. Windows Readlink
is implemented via Windows DeviceIoControl(FSCTL_GET_REPARSE_POINT, ...)
call, but that call does not work on network shares or inside of
Docker container (see issues #18555 ad #19922 for details).
But Raymond Chen suggests different approach:
https://blogs.msdn.microsoft.com/oldnewthing/20100212-00/?p=14963/
- he suggests to use Windows I/O manager to dereferences the
symbolic link.
This appears to work for all normal symlinks, but also for network
shares and inside of Docker container.
This CL implements described procedure.
I also had to adjust TestStatSymlinkLoop, because the test is
expecting Stat to return syscall.ELOOP for symlink with a loop.
But new Stat returns Windows error of ERROR_CANT_RESOLVE_FILENAME
= 1921 instead. I could map ERROR_CANT_RESOLVE_FILENAME into
syscall.ELOOP, but I suspect the former is broader than later.
And ERROR_CANT_RESOLVE_FILENAME message text of "The name of
the file cannot be resolved by the system." sounds fine to me.
Fixes#10935Fixes#18555Fixes#19922
Change-Id: I979636064cdbdb9c7c840cf8ae73fe2c24499879
Reviewed-on: https://go-review.googlesource.com/41834
Reviewed-by: Harshavardhana <hrshvardhana@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
gcc on windows writes invalid location for .debug_gdb_scripts
which causes the executable loading to fail.
Fixes#20183
Change-Id: I5134013bc926b44a55b528f66ab79555855d1f4d
Reviewed-on: https://go-review.googlesource.com/42651
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
As discussion in issue #19141, the addend should be the third
argument of MULA. This patch fixes it in both the front end
and the back end of the assembler. And also tests are added to
the encoding test.
Fixes#19141
Change-Id: Idbc6f338b8fdfcad97a135f27a98c5b375b27d43
Reviewed-on: https://go-review.googlesource.com/42028
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
NewPackage required through documentation that the package name not
be blank (which wasn't true since each time we check a new package
we create one with a blank name (api.go:350). NewPackage also asserted
that a package name not be "_". While it is invalid for a package name
to be "_", one could conceivably create a package named "_" through
export data manipulation. Furthermore, it is ok to import a package
with package path "_" as long as the package itself is not named "_".
- removed misleading documentation
- removed unnecessary assertion
- added safety checks when we actually do the import
Fixes#20231.
Change-Id: I1eb1ab7b5e3130283db715374770cf05d749d159
Reviewed-on: https://go-review.googlesource.com/42852
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
Generated hash and eq routines don't need nil checks.
Prior to this CL, this was accomplished by
temporarily incrementing the global variable disable_checknil.
However, that increment lasted only the lifetime of the
call to funccompile. After CL 41503, funccompile may
do nothing but enqueue the function for compilation,
resulting in nil checks being generated.
Fix this by adding an explicit flag to a function
indicating whether nil checks should be disabled
for that function.
While we're here, allow concurrent compilation
with the -w and -W flags, since that was needed
to investigate this issue.
Fixes#20242
Change-Id: Ib9140c22c49e9a09e62fa3cf350f5d3eff18e2bd
Reviewed-on: https://go-review.googlesource.com/42591
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
The Power processor manual states that "Branches not from the last instruction
of an aligned quadword and not to the first instruction of an aligned quadword
cause inefficiencies in the IBuffer". This changes the function alignment from 8
to 16 bytes to comply with that.
Fixes#18963
Change-Id: Ibce9bf8302110a86c6ab05948569af9ffdfcf4bb
Reviewed-on: https://go-review.googlesource.com/36390
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Allow the predefined escapers "html", "urlquery", and "js" to be used
in pipelines when they have no potential to affect the correctness or
safety of the escaped pipeline output. Specifically:
- "urlquery" may be used if it is the last command in the pipeline.
- "html" may be used if it is the last command in the pipeline, and
the pipeline does not occur in an unquoted HTML attribute value
context.
- "js" may be used in any pipeline, since it does not affect the
merging of contextual escapers.
This change will loosens the restrictions on predefined escapers
introduced in golang.org/cl/37880, which will hopefully ease the
upgrade path for existing template users.
This change brings back the escaper-merging logic, and associated
unit tests, that were removed in golang.org/cl/37880. However, a
few notable changes have been made:
- "_html_template_nospaceescaper" is no longer considered
equivalent to "html", since the former escapes spaces, while
the latter does not (see #19345). This change should not silently
break any templates, since pipelines where this substituion will
happen will already trigger an explicit error.
- An "_eval_args_" internal directive has been added to
handle pipelines containing a single explicit call to a
predefined escaper, e.g. {{html .X}} (see #19353).
Also, the HTMLEscape function called by the predefined
text/template "html" function now escapes the NULL character as
well. This effectively makes it as secure as the internal
html/template HTML escapers (see #19345). While this change is
backward-incompatible, it will only affect illegitimate uses
of this escaper, since the NULL character is always illegal in
valid HTML.
Fixes#19952
Change-Id: I9b5570a80a3ea284b53901e6a1f842fc59b33d3a
Reviewed-on: https://go-review.googlesource.com/40936
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Execute incurs separate writes for each "step", e.g. each
variable that needs to be printed, and the final newline.
While it is correct to state that templates can be executed
concurrently, there is a more subtle nuance that is easily missed:
when writing to the same writer, the writes from concurrent execute
calls can be interleaved, leading to unexpected output.
Change-Id: I0abbd7960d8a8d15e109a8a3eeff3b43b852bbbf
Reviewed-on: https://go-review.googlesource.com/37444
Reviewed-by: Rob Pike <r@golang.org>
The external darwin linker has been printing:
ld: warning: -read_only_relocs cannot be used with x86_64
for a long time. Now that it is printed by CL 33301, we may as
well get rid of it.
Fixes#20246
Change-Id: I1147cf1ff197fdfda228a1349f13627bcf9fc72f
Reviewed-on: https://go-review.googlesource.com/42730
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
For .bss section symbol ldelf does not set P (raw symbol data).
Make ldpe do the same.
Change-Id: Ib3d558456f505ee568d0972465fa9b08b5794a87
Reviewed-on: https://go-review.googlesource.com/42631
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
