Rob Pike [Thu, 15 Aug 2013 00:36:46 +0000 (10:36 +1000)]
cmd/go: fix bad error message in coverage for package without non-test files
Was checking for nil map; must check for empty map instead.
Fixes #6065
Before:
go test -cover
# testmain
/var/folders/00/013l0000h01000cxqpysvccm0004fc/T/go-build233480051/_/Users/r/issue/_test/_testmain.go:11: imported and not used: "_/Users/r/issue"
FAIL _/Users/r/issue [build failed]
Now:
go test -cover
testing: warning: no tests to run
PASS
coverage: 0.0% of statements
ok _/Users/r/issue 0.021s
Carl Shapiro [Wed, 14 Aug 2013 22:21:53 +0000 (15:21 -0700)]
cmd/go, runtime/cgo: explicitly target ARMv5T
The baseline architecture had been left to the GCC configured
default which can be more accomodating than the rest of the Go
toolchain. This prevented instructions used by the 5g compiler,
like BLX, from being used in GCC compiled assembler code.
Dmitriy Vyukov [Wed, 14 Aug 2013 20:20:36 +0000 (00:20 +0400)]
runtime: fix SetBlockProfileRate
It doughtily misses all possible corner cases.
In particular on machines with <1GHz processors,
SetBlockProfileRate(1) disables profiling.
Fixes #6114.
Russ Cox [Wed, 14 Aug 2013 18:54:31 +0000 (14:54 -0400)]
runtime: make SetFinalizer(x, f) accept any f for which f(x) is valid
Originally the requirement was f(x) where f's argument is
exactly x's type.
CL 11858043 relaxed the requirement in a non-standard
way: f's argument must be exactly x's type or interface{}.
If we're going to relax the requirement, it should be done
in a way consistent with the rest of Go. This CL allows f's
argument to have any type for which x is assignable;
that's the same requirement the compiler would impose
if compiling f(x) directly.
Dmitriy Vyukov [Wed, 14 Aug 2013 17:53:27 +0000 (21:53 +0400)]
net: make TCPStress test shorter
It timeouts on freebsd builders:
http://build.golang.org/log/3d8169e13bff912bebf6fd3c54b34ad2d29a7221
but there are always runnable goroutines,
which suggests that it's slowly progressing.
Elias Naur [Wed, 14 Aug 2013 16:47:06 +0000 (12:47 -0400)]
cmd/cgo: fix windows build
The shared library changes broke the windows build because __attribute__ ((visibility ("hidden"))) is not supported in windows gcc. This change removes the attribute, as it is only needed when building shared libraries.
10499043
runtime,cmd/ld: Merge TLS symbols and teach 5l about ARM TLS
This CL prepares for external linking support to ARM.
The pseudo-symbols runtime.g and runtime.m are merged into a single
runtime.tlsgm symbol. When external linking, the offset of a thread local
variable is stored at a memory location instead of being embedded into a offset
of a ldr instruction. With a single runtime.tlsgm symbol for both g and m, only
one such offset is needed.
The larger part of this CL moves TLS code from gcc compiled to internally
compiled. The TLS code now uses the modern MRC instruction, and 5l is taught
about TLS fallbacks in case the instruction is not available or appropriate.
10271047
This CL adds support for -linkmode external to 5l.
For 5l itself, use addrel to allow for D_CALL relocations to be handled by the
host linker. Of the cases listed in rsc's comment in issue 4069, only case 5 and
63 needed an update. One of the TODO: addrel cases was since replaced, and the
rest of the cases are either covered by indirection through addpool (cases with
LTO or LFROM flags) or stubs (case 74). The addpool cases are covered because
addpool emits AWORD instructions, which in turn are handled by case 11.
In the runtime, change the argv argument in the rt0* functions slightly to be a
pointer to the argv list, instead of relying on a particular location of argv.
9733044
The -shared flag to 6l outputs a shared library, implemented in Go
and callable from non-Go programs such as C.
The main part of this CL change the thread local storage model.
Go uses the fastest and least general mode, local exec. TLS data in shared
libraries normally requires at least the local dynamic mode, however, this CL
instead opts for using the initial exec mode. Initial exec mode is faster than
local dynamic mode and can be used in linux since the linker has reserved a
limited amount of TLS space for performance sensitive TLS code.
Initial exec mode requires an extra load from the GOT table to determine the
TLS offset. This penalty will not be paid if ld is not in -shared mode, since
TLS accesses will be reduced to local exec.
The elf sections .init_array and .rela.init_array are added to register the Go
runtime entry with cgo at library load time.
The "hidden" attribute is added to Cgo functions called from Go, since Go
does not generate call through the GOT table, and adding non-GOT relocations for
a global function is not supported by gcc. Cgo symbols don't need to be global
and avoiding the GOT table is also faster.
The changes to 8l are only removes code relevant to the old -shared mode where
internal linking was used.
This CL only address the low level linker work. It can be submitted by itself,
but to be useful, the runtime changes in CL 9738047 is also needed.
Design discussion at
https://groups.google.com/forum/?fromgroups#!topic/golang-nuts/zmjXkGrEx6Q
Dmitriy Vyukov [Wed, 14 Aug 2013 09:56:01 +0000 (13:56 +0400)]
runtime: improve block profiler support for channels
1. Handle select statements.
2. Handle chan close.
3. Show top frame in debug mode (chansend/chanrecv/selectgo).
Fixes #6049.
Brad Fitzpatrick [Tue, 13 Aug 2013 21:48:08 +0000 (14:48 -0700)]
archive/zip: remove an allocation, speed up a test
Update #6138
TestOver65kFiles spends all its time garbage collecting.
Removing the 1.4 MB of allocations per each of the 65k
files brings this from 34 seconds to 0.23 seconds.
Rob Pike [Tue, 13 Aug 2013 21:03:18 +0000 (07:03 +1000)]
cmd/go: nicer error diagnosis in go test
Before,
go test -bench .
would just dump the long generic "go help" message. Confusing and
unhelpful. Now the message is short and on point and also reminds the
user about the oft-forgotten "go help testflag".
% go test -bench
go test: missing argument for flag bench
run "go help test" or "go help testflag" for more information
%
Dmitriy Vyukov [Tue, 13 Aug 2013 18:14:04 +0000 (22:14 +0400)]
runtime: more reliable preemption
Currently it's possible that a goroutine
that periodically executes non-blocking
cgo/syscalls is never preempted.
This change splits scheduler and syscall
ticks to prevent such situation.
Dmitriy Vyukov [Tue, 13 Aug 2013 18:12:02 +0000 (22:12 +0400)]
runtime: do no lose CPU profiling signals
Currently we lose lots of profiling signals.
Most notably, GC is not accounted at all.
But stack splits, scheduler, syscalls, etc are lost as well.
This creates seriously misleading profile.
With this change all profiling signals are accounted.
Now I see these additional entries that were previously absent:
161 29.7% 29.7% 164 30.3% syscall.Syscall
12 2.2% 50.9% 12 2.2% scanblock
11 2.0% 55.0% 11 2.0% markonly
10 1.8% 58.9% 10 1.8% sweepspan
2 0.4% 85.8% 2 0.4% runtime.newstack
It is still impossible to understand what causes stack splits,
but at least it's clear how many time is spent on them.
Update #2197.
Update #5659.
Alberto García Hierro [Tue, 13 Aug 2013 16:42:21 +0000 (12:42 -0400)]
cmd/cgo: Add support for C function pointers
* Add a new kind of Name, "fpvar" which stands for function pointer variable
* When walking the AST, find functions used as expressions and create a new Name object for them
* Track functions which are only used in expr contexts, and avoid generating bridge code for them
Dmitriy Vyukov [Tue, 13 Aug 2013 10:14:24 +0000 (14:14 +0400)]
runtime: eliminate excessive notewakeup calls in timers
If the timer goroutine is wakeup by timeout,
other goroutines will still notewakeup because sleeping is still set.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12763043
Russ Cox [Tue, 13 Aug 2013 04:09:31 +0000 (00:09 -0400)]
cmd/gc: add temporary-merging optimization pass
The compilers assume they can generate temporary variables
as needed to preserve the right semantics or simplify code
generation and the back end will still generate good code.
This turns out not to be true. The back ends will only
track the first 128 variables per function and give up
on the remainder. That needs to be fixed too, in a later CL.
This CL merges temporary variables with equal types and
non-overlapping lifetimes using the greedy algorithm in
Poletto and Sarkar, "Linear Scan Register Allocation",
ACM TOPLAS 1999.
The result can be striking in the right functions.
Top 20 frame size changes in a 6g godoc binary by bytes saved:
Russ Cox [Tue, 13 Aug 2013 02:02:10 +0000 (22:02 -0400)]
cmd/gc: move flow graph into portable opt
Now there's only one copy of the flow graph construction
and dominator computation, and different optimizations
can attach different annotations to the instructions.
Rob Pike [Tue, 13 Aug 2013 01:32:32 +0000 (11:32 +1000)]
go/build: change the wording of NoGoError and comment it better
Out of context, it can be very confusing because there can be lots of Go
files in the directory, but the error message says there aren't.
Elias Naur [Tue, 13 Aug 2013 01:11:05 +0000 (11:11 +1000)]
text/template: Make function call builtin handle nil errors correctly
The call builtin unconditionally tries to convert a second return value from a function to the error type. This fails in case nil is returned, effectively making call useless for functions returning two values.
This CL adds a nil check for the second return value, and adds a test.
Note that for regular function and method calls the nil error case is handled correctly and is verified by a test.
Volker Dobler [Mon, 12 Aug 2013 22:14:34 +0000 (15:14 -0700)]
net/http: do not send malformed cookie domain attribute
Malformed domain attributes are not sent in a Set-Cookie header.
Instead the domain attribute is dropped which turns the cookie
into a host-only cookie. This is much safer than dropping characters
from domain attribute.
Domain attributes with a leading dot '.' are still allowed, even
if discouraged by RFC 6265 section 4.1.1.
Dmitriy Vyukov [Mon, 12 Aug 2013 17:48:19 +0000 (21:48 +0400)]
runtime: remove unused m->racepc
The original plan was to collect allocation stacks
for all memory blocks. But it was never implemented
and it's not in near plans and it's unclear how to do it at all.