The code to do the conversion is smaller than the
call to the runtime.
The 1-result asserts need to call panic if they fail, but that
code is out of line.
The only conversions left in the runtime are those which
might allocate and those which might need to generate an itab.
Given the following types:
type E interface{}
type I interface { foo() }
type I2 iterface { foo(); bar() }
type Big [10]int
func (b Big) foo() { ... }
This CL inlines the following conversions:
was assertE2T
var e E = ...
b := i.(Big)
was assertE2T2
var e E = ...
b, ok := i.(Big)
was assertI2T
var i I = ...
b := i.(Big)
was assertI2T2
var i I = ...
b, ok := i.(Big)
was assertI2E
var i I = ...
e := i.(E)
was assertI2E2
var i I = ...
e, ok := i.(E)
These are the remaining runtime calls:
convT2E:
var b Big = ...
var e E = b
convT2I:
var b Big = ...
var i I = b
convI2I:
var i2 I2 = ...
var i I = i2
assertE2I:
var e E = ...
i := e.(I)
assertE2I2:
var e E = ...
i, ok := e.(I)
assertI2I:
var i I = ...
i2 := i.(I2)
assertI2I2:
var i I = ...
i2, ok := i.(I2)
Fixes#17405Fixes#8422
Change-Id: Ida2367bf8ce3cd2c6bb599a1814f1d275afabe21
Reviewed-on: https://go-review.googlesource.com/32313
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
When T is a scalar, there are no runtime calls
required, which makes this a clear win.
encoding/binary:
WriteInts-8 958ns ± 3% 864ns ± 2% -9.80% (p=0.000 n=15+15)
This also considerably shrinks a core fmt
routine:
Before: "".(*pp).printArg t=1 size=3952 args=0x20 locals=0xf0
After: "".(*pp).printArg t=1 size=2624 args=0x20 locals=0x98
Unfortunately, I find it very hard to get stable
numbers out of the fmt benchmarks due to thermal scaling.
Change-Id: I1278006b030253bf8e48dc7631d18985cdaa143d
Reviewed-on: https://go-review.googlesource.com/26659
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Try to provide hints for common areas, either *interface
were interface would have been better, and note incorrect
capitalization (but don't be more ambitious than that, at
least not today).
Added code and test for cases
ptrInterface.ExistingMethod
ptrInterface.unexportedMethod
ptrInterface.MissingMethod
ptrInterface.withwRongcASEdMethod
interface.withwRongcASEdMethod
ptrStruct.withwRongcASEdMethod
struct.withwRongcASEdMethod
also included tests for related errors to check for
unintentional changes and consistent wording.
Somewhat simplified from previous versions to avoid second-
guessing user errors, yet also biased to point out most-likely
root cause.
Fixes#10700
Change-Id: I16693e93cc8d8ca195e7742a222d640c262105b4
Reviewed-on: https://go-review.googlesource.com/9731
Reviewed-by: Russ Cox <rsc@golang.org>
These can be implemented with just a compare and a move instruction.
Do so, avoiding the overhead of a call into the runtime.
These assertions are a significant cost in Go code that uses interface{}
as a safe alternative to C's void* (or unsafe.Pointer), such as the
current version of the Go compiler.
*T here includes pointer to T but also any Go type represented as
a single pointer (chan, func, map). It does not include [1]*T or struct{*int}.
That requires more work in other parts of the compiler; there is a TODO.
Change-Id: I7ff681c20d2c3eb6ad11dd7b3a37b1f3dda23965
Reviewed-on: https://go-review.googlesource.com/7862
Reviewed-by: Rob Pike <r@golang.org>
The other tests either need a complex procedure
or are architecture- or OS-dependent.
Update #4139.
R=golang-dev, daniel.morsing, iant
CC=golang-dev
https://golang.org/cl/6618062
Today, if run.go doesn't understand a test header line it just ignores
the test, making it too easy to write or edit tests that are not actually
being run.
- expand errorcheck to accept flags, so that bounds.go and escape*.go can run.
- create a whitelist of skippable tests in run.go; skipping others is an error.
- mark all skipped tests at top of file.
Update #4139.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6549054
Accomplished by synchronizing the formatting of conversion errors between typecheck.c and subr.c
Fixes#3984.
R=golang-dev, remyoudompheng, rsc
CC=golang-dev
https://golang.org/cl/6500064
To allow these types as map keys, we must fill in
equal and hash functions in their algorithm tables.
Structs or arrays that are "just memory", like [2]int,
can and do continue to use the AMEM algorithm.
Structs or arrays that contain special values like
strings or interface values use generated functions
for both equal and hash.
The runtime helper func runtime.equal(t, x, y) bool handles
the general equality case for x == y and calls out to
the equal implementation in the algorithm table.
For short values (<= 4 struct fields or array elements),
the sequence of elementwise comparisons is inlined
instead of calling runtime.equal.
R=ken, mpimenov
CC=golang-dev
https://golang.org/cl/5451105
Had been allowing it for use by fmt, but it is too hard to lock down.
Fix other packages not to depend on it.
R=r, r
CC=golang-dev
https://golang.org/cl/5266054
bug363.go:13:12: error: invalid context-determined non-integer type for shift operand
bug363.go:16:12: error: invalid context-determined non-integer type for shift operand
pointer.go:34:6: error: incompatible type in initialization (pointer to interface type has no methods)
pointer.go:36:6: error: incompatible type in initialization
method2.go:15:1: error: invalid pointer or interface receiver type
method2.go:16:1: error: invalid pointer or interface receiver type
method2.go:21:1: error: invalid pointer or interface receiver type
method2.go:22:1: error: invalid pointer or interface receiver type
method2.go:28:15: error: type ‘*Val’ has no method ‘val’
method2.go:33:11: error: reference to undefined field or method ‘val’
shift1.go:19:16: error: invalid context-determined non-integer type for shift operand
shift1.go:24:19: error: invalid context-determined non-integer type for shift operand
shift1.go:25:17: error: invalid context-determined non-integer type for shift operand
shift1.go:18:18: error: shift of non-integer operand
shift1.go:26:13: error: floating point constant truncated to integer
shift1.go:33:15: error: integer constant overflow
shift1.go:34:15: error: integer constant overflow
shift1.go:35:17: error: integer constant overflow
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5081051
// ERROR "pattern1" "pattern2"
means that there has to be one or more
lines matching pattern1 and then excluding
those, there have to be one or more lines
matching pattern2. So if you expect two
different error messages from a particular
line, writing two separate patterns checks
that both errors are produced.
Also, errchk now flags lines that produce
more errors than expected. Before, as long as
at least one error matched the pattern, all the
others were ignored.
Revise tests to expect or silence these
additional errors.
R=lvd, r, iant
CC=golang-dev
https://golang.org/cl/4869044
explicit.go:36:4: error: incompatible types in assignment (need explicit conversion)
explicit.go:41:4: error: incompatible types in assignment (type has no methods)
explicit.go:42:4: error: incompatible types in assignment (need explicit conversion)
explicit.go:45:5: error: incompatible types in assignment (need explicit conversion; missing method ‘N’)
explicit.go:48:9: error: invalid type conversion (need explicit conversion; missing method ‘N’)
explicit.go:51:4: error: incompatible types in assignment
explicit.go:51:7: error: invalid type conversion (need explicit conversion)
explicit.go:57:10: error: impossible type assertion: type does not implement interface (type has no methods)
explicit.go:62:10: error: impossible type assertion: type does not implement interface (incompatible type for method ‘M’ (different number of parameters))
explicit.go:67:5: error: incompatible type in initialization (type has no methods)
explicit.go:68:5: error: incompatible type in initialization (incompatible type for method ‘M’ (different number of parameters))
explicit.go:70:11: error: invalid type conversion (type has no methods)
explicit.go:71:11: error: invalid type conversion (incompatible type for method ‘M’ (different number of parameters))
R=rsc
CC=golang-dev
https://golang.org/cl/2139044
* Code for assignment, conversions now mirrors spec.
* Changed some snprint -> smprint.
* Renamed runtime functions to separate
interface conversions from type assertions:
convT2I, assertI2T, etc.
* Correct checking of \U sequences.
Fixes#840.
Fixes#830.
Fixes#778.
R=ken2
CC=golang-dev
https://golang.org/cl/1303042
note that sortmain.go has been run through hg gofmt;
only the formatting of the day initializers changed.
i'm happy to revert that formatting if you'd prefer.
stop on error in doc/progs/run
R=r
CC=golang-dev
https://golang.org/cl/850041
