This CL changes the encoding used for the Go symbol table,
stored in the binary and used at run time. It does not change
any of the semantics or structure: the bits are just packed
a little differently.
The comment at the top of runtime/symtab.c describes the new format.
Compared to the Go 1.0 format, the main changes are:
* Store symbol addresses as full-pointer-sized host-endian values.
(For 6g, this means addresses are 64-bit little-endian.)
* Store other values (frame sizes and so on) varint-encoded.
The second change more than compensates for the first:
for the godoc binary on OS X/amd64, the new symbol table
is 8% smaller than the old symbol table (1,425,668 down from 1,546,276).
This is a required step for allowing the host linker (gcc) to write
the final Go binary, since it will have to fill in the symbol address slots
(so the slots must be host-endian) and on 64-bit systems it may
choose addresses above 4 GB.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7403054
Actually it already worked since the spec only requires that
the one immediately preceding a for/switch/... be usable as
the target of a break or continue statement.
Added a test.
Also: allocate Function.lblocks on first use.
R=gri
CC=golang-dev
https://golang.org/cl/7365058
And fix test. Pointer to unsafe.Pointer tests nothing important...
Also identify the incorrect type: go/types.Type is a Stringer.
Also fix a couple of incorrect format verbs found by new printf checker,
now that we can run it on more files.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7385051
The previous approach desugared the ast.SelectorExpr
to make implicit field selections explicit. But:
1) it was clunky since it required allocating temporary
syntax trees.
2) it was not thread-safe since it required poking
types into the shared type map for the new ASTs.
3) the desugared syntax had no place to represent the
package lexically enclosing each implicit field
selection, so it was as if they all occurred in the
same package as the explicit field selection.
This meant unexported field names changed meaning.
This CL does what I should have done all along: just
generate the SSA instructions directly from the original
AST and the promoted field information.
Also:
- add logStack util for paired start/end log messages.
Useful for debugging crashes.
R=gri
CC=golang-dev
https://golang.org/cl/7395052
Adjust the exit status string for Plan 9.
Upon allocating >100 file descriptors, Plan 9
raises a warning. Moreover, the Go runtime for
32-bit version of Plan 9 keeps /dev/bintime
open for its implementation of runtime.nanotime().
This change accounts for these things in
TestExtraFiles.
R=rsc, rminnich, ality, bradfitz
CC=golang-dev
https://golang.org/cl/7363056
Context.Alignof/Offsetsof/Sizeof now provide means
to customize the type checker for a given platform.
- provide Context.Offsetsof to specify the
offsets of struct fields
- use the correct sizes for ints, uint, uintptrs
in constant computations
- moved all size computations into separate file
(sizes.go)
- fixed a bug with string constant slicing
R=adonovan, axwalk
CC=golang-dev
https://golang.org/cl/7363054
- imported objects don't have position information
- gc exported data contains non-exported objects at
the top-level, guard against them
- better error message when dot-imports conflict
with local declarations
R=adonovan, r
CC=golang-dev
https://golang.org/cl/7379052
pkg/go/doc: move BUG notes from Package.Bugs to the general Package.Notes field.
Removing .Bugs would break existing code so it's left in for now.
R=gri, gri, gary.burd, dsymonds, rsc, kevlar
CC=golang-dev
https://golang.org/cl/7341053
Separates the implementation of nanotime on 64-bit
version of Plan 9 from that on the 32-bit version.
The former uses a syscall.
R=rsc, rminnich, ality
CC=golang-dev
https://golang.org/cl/7379051
Also restores the checking of _test.go files, which disappeared
as a result of the package-at-a-time change.
Fixes#4895.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7399051
Functions for representing network connections as files
and vice versa, on Plan 9.
Representing network connections as files is not so
straight-forward, because a network connection on Plan 9
is represented by a host of files rather than a single
file descriptor (as is the case on UNIX). We use the
type system to distinguish between listeners and
connections, returning the control file in the former
case and the data file in the latter case.
R=rsc, rminnich, ality, akumar, bradfitz
CC=golang-dev
https://golang.org/cl/7235068
Then mark them with a build tag so they're not compiled into the binary.
They are called test_*.go rather than *_test.go because they are not
for go test. Use make test to test the command.
R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/7377052
Composite literals using the &T{} form were incorrectly
exported, leading to weird errors at import time.
Fixes#4879.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7395054
This avoids an allocation when closures are used
as "macros", in Walk idioms, or as argument to defer.
benchmark old ns/op new ns/op delta
BenchmarkSearchWrappers 1171 354 -69.77%
BenchmarkCallClosure 3 3 -12.54%
BenchmarkCallClosure1 119 7 -93.95%
BenchmarkCallClosure2 183 74 -59.18%
BenchmarkCallClosure3 187 75 -59.57%
BenchmarkCallClosure4 187 76 -58.98%
Compared to Go 1:
benchmark old ns/op new ns/op delta
BenchmarkSearchWrappers 3208 354 -88.97%
Fixes#3520.
R=daniel.morsing, bradfitz, minux.ma, dave, rsc
CC=golang-dev
https://golang.org/cl/7397056
Syscalls return `-1' on error and the representation is always
32-bits. The `$-1' literal in 64-bit assembly is always the
64-bit representation. So this change makes sure that we
always do a 32-bit comparison when checking for error.
Also makes sure that in the error case, we return a 64-bit
`-1' from runtime.seek.
Fixes the arithmetic for handling the error-string in
runtime.Syscall6.
R=golang-dev, rminnich, rsc, ality, minux.ma
CC=golang-dev
https://golang.org/cl/7399052
sigprocmask() is process-wide on darwin, so two concurrent
libcgo_sys_thread_start() can result in all signals permanently
blocked, which in particular blocks handling of nil derefs.
Fixes#4833.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/7324058
Now that the type information is in TYPE instructions
that are not rewritten by the optimization passes,
we don't have to try to preserve the type information
(no longer) attached to MOV instructions.
R=ken2
CC=golang-dev
https://golang.org/cl/7402054
Now that vet does typechecking, it should use only pkg.gofiles, instead
of pkg.allgofiles. Ignored files should not be checked by vet, because
they wouldn't typecheck.
Fixes#4906.
R=rsc, r
CC=golang-dev
https://golang.org/cl/7401051
The type information is (and for years has been) included
as an extra field in the address chunk of an instruction.
Unfortunately, suppose there is a string at a+24(FP) and
we have an instruction reading its length. It will say:
MOVQ x+32(FP), AX
and the type of *that* argument is int (not slice), because
it is the length being read. This confuses the picture seen
by debuggers and now, worse, by the garbage collector.
Instead of attaching the type information to all uses,
emit an explicit list of TYPE instructions with the information.
The TYPE instructions are no-ops whose only role is to
provide an address to attach type information to.
For example, this function:
func f(x, y, z int) (a, b string) {
return
}
now compiles into:
--- prog list "f" ---
0000 (/Users/rsc/x.go:3) TEXT f+0(SB),$0-56
0001 (/Users/rsc/x.go:3) LOCALS ,
0002 (/Users/rsc/x.go:3) TYPE x+0(FP){int},$8
0003 (/Users/rsc/x.go:3) TYPE y+8(FP){int},$8
0004 (/Users/rsc/x.go:3) TYPE z+16(FP){int},$8
0005 (/Users/rsc/x.go:3) TYPE a+24(FP){string},$16
0006 (/Users/rsc/x.go:3) TYPE b+40(FP){string},$16
0007 (/Users/rsc/x.go:3) MOVQ $0,b+40(FP)
0008 (/Users/rsc/x.go:3) MOVQ $0,b+48(FP)
0009 (/Users/rsc/x.go:3) MOVQ $0,a+24(FP)
0010 (/Users/rsc/x.go:3) MOVQ $0,a+32(FP)
0011 (/Users/rsc/x.go:4) RET ,
The { } show the formerly hidden type information.
The { } syntax is used when printing from within the gc compiler.
It is not accepted by the assemblers.
The same type information is now included on global variables:
0055 (/Users/rsc/x.go:15) GLOBL slice+0(SB){[]string},$24(AL*0)
This more accurate type information fixes a bug in the
garbage collector's precise heap collection.
The linker only cares about globals right now, but having the
local information should make things a little nicer for Carl
in the future.
Fixes#4907.
R=ken2
CC=golang-dev
https://golang.org/cl/7395056
It's accessed without mutex protection
in a different goroutine from the one that
sets it.
Also make sure that Client.Call after Client.Close
will reliably return ErrShutdown, and that clients
see ErrShutdown rather than io.EOF when appropriate.
Suggestions welcome for a way to reliably test
the mutex issue.
R=r, iant
CC=golang-dev
https://golang.org/cl/7338045
Added the command line flag -ex to godoc to print examples in
text output.
Samples from the generated output:
$ godoc -ex strings Index
...
func Index(s, sep string) int
Index returns the index of the first instance of sep in s, or -1 if sep
is not present in s.
Example:
fmt.Println(strings.Index("chicken", "ken"))
fmt.Println(strings.Index("chicken", "dmr"))
// Output:
// 4
// -1
...
$ godoc -ex container/heap
...
package heap
import "container/heap"
Package heap provides heap operations for any type that implements
heap.Interface. A heap is a tree with the property that each node is the
minimum-valued node in its subtree.
Example:
// This example demonstrates an integer heap built using the heap interface.
package heap_test
import (
"container/heap"
"fmt"
...
Example:
// This example demonstrates a priority queue built using the heap interface.
package heap_test
import (
"container/heap"
"fmt"
)
...
Fixes#3587.
R=golang-dev, minux.ma, adg, rsc, gri
CC=golang-dev
https://golang.org/cl/7356043
