Make the loop nesting depth of &x depend on where x is declared,
not on where the &x appears. The latter is only a conservative
estimate of the former. Being more careful can avoid some
variables escaping, and it is easier to reason about.
It would have avoided issue 7313, although that was still a bug
worth fixing.
Not much effect in the tree: one variable in the whole tree
is saved from a heap allocation (something in x509 parsing).
LGTM=daniel.morsing
R=daniel.morsing
CC=golang-codereviews
https://golang.org/cl/62380043
Logically, the init statement is in the enclosing scopes loopdepth, not inside the for loop.
Fixes#7313.
LGTM=rsc
R=golang-codereviews, gobot, rsc
CC=golang-codereviews
https://golang.org/cl/62430043
Functions without bodies were excluded from the ordering logic,
because when I wrote the ordering logic there was no reason to
analyze them.
But then we added //go:noescape tags that need analysis, and we
didn't update the ordering logic.
So in the absence of good ordering, //go:noescape only worked
if it appeared before the use in the source code.
Fixes#5773.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/10570043
It used to not mark parameters as escaping if only one of the
fields it points to leaks out of the function. This causes
problems when importing from another package.
Fixes#4964.
R=rsc, lvd, dvyukov, daniel.morsing
CC=golang-dev
https://golang.org/cl/7648045
A new comment directive //go:noescape instructs the compiler
that the following external (no body) func declaration should be
treated as if none of its arguments escape to the heap.
Fixes#4099.
R=golang-dev, dave, minux.ma, daniel.morsing, remyoudompheng, adg, agl, iant
CC=golang-dev
https://golang.org/cl/7289048
If the analysis reached a node twice, then the analysis was cut off.
However, if the second arrival is at a lower depth (closer to escaping)
then it is important to repeat the traversal.
The repeating must be cut off at some point to avoid the occasional
infinite recursion. This CL cuts it off as soon as possible while still
passing all tests.
Fixes#4751.
R=ken2
CC=golang-dev, lvd
https://golang.org/cl/7303043
A fatal error used to happen when escassign-ing a multiple
function return to a single node. However, the situation
naturally appears when using "go f(g())" or "defer f(g())",
because g() is escassign-ed to sink.
Fixes#4529.
R=golang-dev, lvd, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6920060
includes step 0: synthesize outparams, from 6600044
includes step 1,2: give outparams loopdepth 0 and verify unchanged results
generate esc:$mask tags, but still tie to sink if a param has mask != 0
from 6610054
adds final steps:
- have esccall generate n->escretval, a list of nodes the function results flow to
- use these in esccall and ORETURN/OAS2FUNC/and f(g())
- only tie parameters to sink if tag is absent, otherwise according to mask, tie them to escretval
R=rsc, bradfitz
CC=dave, gobot, golang-dev, iant, rsc
https://golang.org/cl/6741044
Was not handling &x.y[0] and &x.y.z correctly where
y is an array or struct-valued field (not a pointer).
R=ken2
CC=golang-dev
https://golang.org/cl/6551059
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
The escape analysis code does not make a distinction between
scalar and pointers fields in structs. Non-pointer fields
that escape should not make the whole struct escape.
R=lvd, rsc
CC=golang-dev, remy
https://golang.org/cl/5489128
This avoids degraded performance caused by extra labels
emitted by inlining (breaking strconv ftoa alloc count unittest) and is better in any case.
R=rsc
CC=golang-dev
https://golang.org/cl/5483071
mark OADDR inserted by typecheck as implicit
OCOPY takes ->left and ->right, not ->list
OMAKE*'s can all have arguments
precedence for OIND was initalized twice
fixes#2414
R=rsc, dave
CC=golang-dev
https://golang.org/cl/5319065
string literals used as package qualifiers are now prefixed with '@'
which obviates the need for the extra ':' before tags.
R=rsc, gri, lvd
CC=golang-dev
https://golang.org/cl/5129057
Was keeping a pointer to the labeled statement in n->right,
which meant that generic traversals of the tree visited it twice.
That combined with aggressive flattening of the block
structure when possible during parsing meant that
the kinds of label: code label: code label: code sequences
generated by yacc were giving the recursion 2ⁿ paths
through the program.
Fixes#2212.
R=lvd
CC=golang-dev
https://golang.org/cl/4960050
Escape analysis was incorrectly assuming that
functions without bodies don't leak their
parameters. This meant that sync/atomic's
TestAddInt64 was allocating x on its stack,
and then x was not properly aligned for use
with the atomic 64-bit instructions. Obviously
we should figure out the alignment story on 5g
too, but this fix is correct and should restore the
build to 'ok'.
TBR=lvd
CC=golang-dev
https://golang.org/cl/4964047
-s now means *disable* escape analysis.
Fix escape leaks for struct/slice/map literals.
Add ... tracking.
Rewrite new(T) and slice literal into stack allocation when safe.
Add annotations to reflect.
Reflect is too chummy with the compiler,
so changes like these affect it more than they should.
R=lvd, dave, gustavo
CC=golang-dev
https://golang.org/cl/4954043
For now it's switch-on-and-offable with -s, and the effects can be inspected
with -m. Defaults are the old codepaths.
R=rsc
CC=golang-dev
https://golang.org/cl/4634073