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[dev.regabi] cmd/compile: split out package escape [generated]

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[git-generate]

cd src/cmd/compile/internal/gc
rf '
	# Trivial min, max defined in escape.go but only used in ssa.go.
	mv min8 max8 ssa.go

	# Export package escape API.
	mv escapes Funcs
	mv escapeFuncs Batch
	mv escFmt Fmt
	mv unsafeUintptrTag UnsafeUintptrNote
	mv uintptrEscapesTag UintptrEscapesNote
	mv heapAllocReason HeapAllocReason

	# Unexport non-API.
	mv EscEdge edge
	mv EscHole hole
	mv EscLeaks leaks
	mv ParseLeaks parseLeaks
	mv EscLocation location
	mv EscNote note
	mv Escape _escape # leave room for escape import, fixed below
	mv EscFuncUnknown escFuncUnknown
	mv EscFuncPlanned escFuncPlanned
	mv EscFuncStarted escFuncStarted
	mv EscFuncTagged escFuncTagged

	mv escape.go cmd/compile/internal/escape
'
cd ../escape
rf '
	mv _escape escape
'

Change-Id: I3a6d1bfb6eba12bea936354ea1fe9813cbde425c
Reviewed-on: https://go-review.googlesource.com/c/go/+/279472
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This commit is contained in:
Russ Cox 2020-12-23 00:51:28 -05:00
parent 071ab0a14c
commit de454eef5f
7 changed files with 156 additions and 150 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

275
src/cmd/compile/internal/gc/escape.go → src/cmd/compile/internal/escape/escape.go
View File

@ -2,18 +2,19 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package gc
package escape
import (
"fmt"
"math"
"strings"
"cmd/compile/internal/base"
"cmd/compile/internal/ir"
"cmd/compile/internal/logopt"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
"cmd/internal/src"
"fmt"
"math"
"strings"
)
// Escape analysis.
@ -84,8 +85,8 @@ import (
// u[2], etc. However, we do record the implicit dereference involved
// in indexing a slice.
type Escape struct {
allLocs []*EscLocation
type escape struct {
allLocs []*location
labels map[*types.Sym]labelState // known labels
curfn *ir.Func
@ -96,17 +97,17 @@ type Escape struct {
// unstructured loop).
loopDepth int
heapLoc EscLocation
blankLoc EscLocation
heapLoc location
blankLoc location
}
// An EscLocation represents an abstract location that stores a Go
// An location represents an abstract location that stores a Go
// variable.
type EscLocation struct {
n ir.Node // represented variable or expression, if any
curfn *ir.Func // enclosing function
edges []EscEdge // incoming edges
loopDepth int // loopDepth at declaration
type location struct {
n ir.Node // represented variable or expression, if any
curfn *ir.Func // enclosing function
edges []edge // incoming edges
loopDepth int // loopDepth at declaration
// derefs and walkgen are used during walkOne to track the
// minimal dereferences from the walk root.
@ -116,7 +117,7 @@ type EscLocation struct {
// dst and dstEdgeindex track the next immediate assignment
// destination location during walkone, along with the index
// of the edge pointing back to this location.
dst *EscLocation
dst *location
dstEdgeIdx int
// queued is used by walkAll to track whether this location is
@ -134,18 +135,18 @@ type EscLocation struct {
transient bool
// paramEsc records the represented parameter's leak set.
paramEsc EscLeaks
paramEsc leaks
}
// An EscEdge represents an assignment edge between two Go variables.
type EscEdge struct {
src *EscLocation
// An edge represents an assignment edge between two Go variables.
type edge struct {
src *location
derefs int // >= -1
notes *EscNote
notes *note
}
// escFmt is called from node printing to print information about escape analysis results.
func escFmt(n ir.Node) string {
// Fmt is called from node printing to print information about escape analysis results.
func Fmt(n ir.Node) string {
text := ""
switch n.Esc() {
case ir.EscUnknown:
@ -164,7 +165,7 @@ func escFmt(n ir.Node) string {
text = fmt.Sprintf("esc(%d)", n.Esc())
}
if e, ok := n.Opt().(*EscLocation); ok && e.loopDepth != 0 {
if e, ok := n.Opt().(*location); ok && e.loopDepth != 0 {
if text != "" {
text += " "
}
@ -173,16 +174,16 @@ func escFmt(n ir.Node) string {
return text
}
// escapeFuncs performs escape analysis on a minimal batch of
// Batch performs escape analysis on a minimal batch of
// functions.
func escapeFuncs(fns []*ir.Func, recursive bool) {
func Batch(fns []*ir.Func, recursive bool) {
for _, fn := range fns {
if fn.Op() != ir.ODCLFUNC {
base.Fatalf("unexpected node: %v", fn)
}
}
var e Escape
var e escape
e.heapLoc.escapes = true
// Construct data-flow graph from syntax trees.
@ -198,11 +199,11 @@ func escapeFuncs(fns []*ir.Func, recursive bool) {
e.finish(fns)
}
func (e *Escape) initFunc(fn *ir.Func) {
if fn.Esc() != EscFuncUnknown {
func (e *escape) initFunc(fn *ir.Func) {
if fn.Esc() != escFuncUnknown {
base.Fatalf("unexpected node: %v", fn)
}
fn.SetEsc(EscFuncPlanned)
fn.SetEsc(escFuncPlanned)
if base.Flag.LowerM > 3 {
ir.Dump("escAnalyze", fn)
}
@ -218,8 +219,8 @@ func (e *Escape) initFunc(fn *ir.Func) {
}
}
func (e *Escape) walkFunc(fn *ir.Func) {
fn.SetEsc(EscFuncStarted)
func (e *escape) walkFunc(fn *ir.Func) {
fn.SetEsc(escFuncStarted)
// Identify labels that mark the head of an unstructured loop.
ir.Visit(fn, func(n ir.Node) {
@ -277,7 +278,7 @@ func (e *Escape) walkFunc(fn *ir.Func) {
// }
// stmt evaluates a single Go statement.
func (e *Escape) stmt(n ir.Node) {
func (e *escape) stmt(n ir.Node) {
if n == nil {
return
}
@ -368,7 +369,7 @@ func (e *Escape) stmt(n ir.Node) {
n := n.(*ir.SwitchStmt)
typesw := n.Tag != nil && n.Tag.Op() == ir.OTYPESW
var ks []EscHole
var ks []hole
for _, cas := range n.Cases { // cases
cas := cas.(*ir.CaseStmt)
if typesw && n.Tag.(*ir.TypeSwitchGuard).Tag != nil {
@ -456,14 +457,14 @@ func (e *Escape) stmt(n ir.Node) {
}
}
func (e *Escape) stmts(l ir.Nodes) {
func (e *escape) stmts(l ir.Nodes) {
for _, n := range l {
e.stmt(n)
}
}
// block is like stmts, but preserves loopDepth.
func (e *Escape) block(l ir.Nodes) {
func (e *escape) block(l ir.Nodes) {
old := e.loopDepth
e.stmts(l)
e.loopDepth = old
@ -471,7 +472,7 @@ func (e *Escape) block(l ir.Nodes) {
// expr models evaluating an expression n and flowing the result into
// hole k.
func (e *Escape) expr(k EscHole, n ir.Node) {
func (e *escape) expr(k hole, n ir.Node) {
if n == nil {
return
}
@ -479,7 +480,7 @@ func (e *Escape) expr(k EscHole, n ir.Node) {
e.exprSkipInit(k, n)
}
func (e *Escape) exprSkipInit(k EscHole, n ir.Node) {
func (e *escape) exprSkipInit(k hole, n ir.Node) {
if n == nil {
return
}
@ -590,7 +591,7 @@ func (e *Escape) exprSkipInit(k EscHole, n ir.Node) {
e.discard(n.X)
case ir.OCALLMETH, ir.OCALLFUNC, ir.OCALLINTER, ir.OLEN, ir.OCAP, ir.OCOMPLEX, ir.OREAL, ir.OIMAG, ir.OAPPEND, ir.OCOPY:
e.call([]EscHole{k}, n, nil)
e.call([]hole{k}, n, nil)
case ir.ONEW:
n := n.(*ir.UnaryExpr)
@ -627,7 +628,7 @@ func (e *Escape) exprSkipInit(k EscHole, n ir.Node) {
//
// TODO(mdempsky): Change ks into a callback, so that
// we don't have to create this slice?
var ks []EscHole
var ks []hole
for i := m.Type.NumResults(); i > 0; i-- {
ks = append(ks, e.heapHole())
}
@ -709,7 +710,7 @@ func (e *Escape) exprSkipInit(k EscHole, n ir.Node) {
// unsafeValue evaluates a uintptr-typed arithmetic expression looking
// for conversions from an unsafe.Pointer.
func (e *Escape) unsafeValue(k EscHole, n ir.Node) {
func (e *escape) unsafeValue(k hole, n ir.Node) {
if n.Type().Kind() != types.TUINTPTR {
base.Fatalf("unexpected type %v for %v", n.Type(), n)
}
@ -751,11 +752,11 @@ func (e *Escape) unsafeValue(k EscHole, n ir.Node) {
// discard evaluates an expression n for side-effects, but discards
// its value.
func (e *Escape) discard(n ir.Node) {
func (e *escape) discard(n ir.Node) {
e.expr(e.discardHole(), n)
}
func (e *Escape) discards(l ir.Nodes) {
func (e *escape) discards(l ir.Nodes) {
for _, n := range l {
e.discard(n)
}
@ -763,7 +764,7 @@ func (e *Escape) discards(l ir.Nodes) {
// addr evaluates an addressable expression n and returns an EscHole
// that represents storing into the represented location.
func (e *Escape) addr(n ir.Node) EscHole {
func (e *escape) addr(n ir.Node) hole {
if n == nil || ir.IsBlank(n) {
// Can happen in select case, range, maybe others.
return e.discardHole()
@ -809,8 +810,8 @@ func (e *Escape) addr(n ir.Node) EscHole {
return k
}
func (e *Escape) addrs(l ir.Nodes) []EscHole {
var ks []EscHole
func (e *escape) addrs(l ir.Nodes) []hole {
var ks []hole
for _, n := range l {
ks = append(ks, e.addr(n))
}
@ -818,7 +819,7 @@ func (e *Escape) addrs(l ir.Nodes) []EscHole {
}
// assign evaluates the assignment dst = src.
func (e *Escape) assign(dst, src ir.Node, why string, where ir.Node) {
func (e *escape) assign(dst, src ir.Node, why string, where ir.Node) {
// Filter out some no-op assignments for escape analysis.
ignore := dst != nil && src != nil && isSelfAssign(dst, src)
if ignore && base.Flag.LowerM != 0 {
@ -836,14 +837,14 @@ func (e *Escape) assign(dst, src ir.Node, why string, where ir.Node) {
}
}
func (e *Escape) assignHeap(src ir.Node, why string, where ir.Node) {
func (e *escape) assignHeap(src ir.Node, why string, where ir.Node) {
e.expr(e.heapHole().note(where, why), src)
}
// call evaluates a call expressions, including builtin calls. ks
// should contain the holes representing where the function callee's
// results flows; where is the OGO/ODEFER context of the call, if any.
func (e *Escape) call(ks []EscHole, call, where ir.Node) {
func (e *escape) call(ks []hole, call, where ir.Node) {
topLevelDefer := where != nil && where.Op() == ir.ODEFER && e.loopDepth == 1
if topLevelDefer {
// force stack allocation of defer record, unless
@ -851,7 +852,7 @@ func (e *Escape) call(ks []EscHole, call, where ir.Node) {
where.SetEsc(ir.EscNever)
}
argument := func(k EscHole, arg ir.Node) {
argument := func(k hole, arg ir.Node) {
if topLevelDefer {
// Top level defers arguments don't escape to
// heap, but they do need to last until end of
@ -969,7 +970,7 @@ func (e *Escape) call(ks []EscHole, call, where ir.Node) {
// ks should contain the holes representing where the function
// callee's results flows. fn is the statically-known callee function,
// if any.
func (e *Escape) tagHole(ks []EscHole, fn *ir.Name, param *types.Field) EscHole {
func (e *escape) tagHole(ks []hole, fn *ir.Name, param *types.Field) hole {
// If this is a dynamic call, we can't rely on param.Note.
if fn == nil {
return e.heapHole()
@ -981,15 +982,15 @@ func (e *Escape) tagHole(ks []EscHole, fn *ir.Name, param *types.Field) EscHole
// Call to previously tagged function.
if param.Note == uintptrEscapesTag {
if param.Note == UintptrEscapesNote {
k := e.heapHole()
k.uintptrEscapesHack = true
return k
}
var tagKs []EscHole
var tagKs []hole
esc := ParseLeaks(param.Note)
esc := parseLeaks(param.Note)
if x := esc.Heap(); x >= 0 {
tagKs = append(tagKs, e.heapHole().shift(x))
}
@ -1010,9 +1011,9 @@ func (e *Escape) tagHole(ks []EscHole, fn *ir.Name, param *types.Field) EscHole
// fn has not yet been analyzed, so its parameters and results
// should be incorporated directly into the flow graph instead of
// relying on its escape analysis tagging.
func (e *Escape) inMutualBatch(fn *ir.Name) bool {
if fn.Defn != nil && fn.Defn.Esc() < EscFuncTagged {
if fn.Defn.Esc() == EscFuncUnknown {
func (e *escape) inMutualBatch(fn *ir.Name) bool {
if fn.Defn != nil && fn.Defn.Esc() < escFuncTagged {
if fn.Defn.Esc() == escFuncUnknown {
base.Fatalf("graph inconsistency")
}
return true
@ -1020,31 +1021,31 @@ func (e *Escape) inMutualBatch(fn *ir.Name) bool {
return false
}
// An EscHole represents a context for evaluation a Go
// An hole represents a context for evaluation a Go
// expression. E.g., when evaluating p in "x = **p", we'd have a hole
// with dst==x and derefs==2.
type EscHole struct {
dst *EscLocation
type hole struct {
dst *location
derefs int // >= -1
notes *EscNote
notes *note
// uintptrEscapesHack indicates this context is evaluating an
// argument for a //go:uintptrescapes function.
uintptrEscapesHack bool
}
type EscNote struct {
next *EscNote
type note struct {
next *note
where ir.Node
why string
}
func (k EscHole) note(where ir.Node, why string) EscHole {
func (k hole) note(where ir.Node, why string) hole {
if where == nil || why == "" {
base.Fatalf("note: missing where/why")
}
if base.Flag.LowerM >= 2 || logopt.Enabled() {
k.notes = &EscNote{
k.notes = &note{
next: k.notes,
where: where,
why: why,
@ -1053,7 +1054,7 @@ func (k EscHole) note(where ir.Node, why string) EscHole {
return k
}
func (k EscHole) shift(delta int) EscHole {
func (k hole) shift(delta int) hole {
k.derefs += delta
if k.derefs < -1 {
base.Fatalf("derefs underflow: %v", k.derefs)
@ -1061,10 +1062,10 @@ func (k EscHole) shift(delta int) EscHole {
return k
}
func (k EscHole) deref(where ir.Node, why string) EscHole { return k.shift(1).note(where, why) }
func (k EscHole) addr(where ir.Node, why string) EscHole { return k.shift(-1).note(where, why) }
func (k hole) deref(where ir.Node, why string) hole { return k.shift(1).note(where, why) }
func (k hole) addr(where ir.Node, why string) hole { return k.shift(-1).note(where, why) }
func (k EscHole) dotType(t *types.Type, where ir.Node, why string) EscHole {
func (k hole) dotType(t *types.Type, where ir.Node, why string) hole {
if !t.IsInterface() && !types.IsDirectIface(t) {
k = k.shift(1)
}
@ -1073,7 +1074,7 @@ func (k EscHole) dotType(t *types.Type, where ir.Node, why string) EscHole {
// teeHole returns a new hole that flows into each hole of ks,
// similar to the Unix tee(1) command.
func (e *Escape) teeHole(ks ...EscHole) EscHole {
func (e *escape) teeHole(ks ...hole) hole {
if len(ks) == 0 {
return e.discardHole()
}
@ -1101,7 +1102,7 @@ func (e *Escape) teeHole(ks ...EscHole) EscHole {
return loc.asHole()
}
func (e *Escape) dcl(n ir.Node) EscHole {
func (e *escape) dcl(n ir.Node) hole {
loc := e.oldLoc(n)
loc.loopDepth = e.loopDepth
return loc.asHole()
@ -1110,7 +1111,7 @@ func (e *Escape) dcl(n ir.Node) EscHole {
// spill allocates a new location associated with expression n, flows
// its address to k, and returns a hole that flows values to it. It's
// intended for use with most expressions that allocate storage.
func (e *Escape) spill(k EscHole, n ir.Node) EscHole {
func (e *escape) spill(k hole, n ir.Node) hole {
loc := e.newLoc(n, true)
e.flow(k.addr(n, "spill"), loc)
return loc.asHole()
@ -1119,7 +1120,7 @@ func (e *Escape) spill(k EscHole, n ir.Node) EscHole {
// later returns a new hole that flows into k, but some time later.
// Its main effect is to prevent immediate reuse of temporary
// variables introduced during Order.
func (e *Escape) later(k EscHole) EscHole {
func (e *escape) later(k hole) hole {
loc := e.newLoc(nil, false)
e.flow(k, loc)
return loc.asHole()
@ -1138,7 +1139,7 @@ func canonicalNode(n ir.Node) ir.Node {
return n
}
func (e *Escape) newLoc(n ir.Node, transient bool) *EscLocation {
func (e *escape) newLoc(n ir.Node, transient bool) *location {
if e.curfn == nil {
base.Fatalf("e.curfn isn't set")
}
@ -1147,7 +1148,7 @@ func (e *Escape) newLoc(n ir.Node, transient bool) *EscLocation {
}
n = canonicalNode(n)
loc := &EscLocation{
loc := &location{
n: n,
curfn: e.curfn,
loopDepth: e.loopDepth,
@ -1165,23 +1166,23 @@ func (e *Escape) newLoc(n ir.Node, transient bool) *EscLocation {
}
n.SetOpt(loc)
if why := heapAllocReason(n); why != "" {
if why := HeapAllocReason(n); why != "" {
e.flow(e.heapHole().addr(n, why), loc)
}
}
return loc
}
func (e *Escape) oldLoc(n ir.Node) *EscLocation {
func (e *escape) oldLoc(n ir.Node) *location {
n = canonicalNode(n)
return n.Opt().(*EscLocation)
return n.Opt().(*location)
}
func (l *EscLocation) asHole() EscHole {
return EscHole{dst: l}
func (l *location) asHole() hole {
return hole{dst: l}
}
func (e *Escape) flow(k EscHole, src *EscLocation) {
func (e *escape) flow(k hole, src *location) {
dst := k.dst
if dst == &e.blankLoc {
return
@ -1206,15 +1207,15 @@ func (e *Escape) flow(k EscHole, src *EscLocation) {
}
// TODO(mdempsky): Deduplicate edges?
dst.edges = append(dst.edges, EscEdge{src: src, derefs: k.derefs, notes: k.notes})
dst.edges = append(dst.edges, edge{src: src, derefs: k.derefs, notes: k.notes})
}
func (e *Escape) heapHole() EscHole { return e.heapLoc.asHole() }
func (e *Escape) discardHole() EscHole { return e.blankLoc.asHole() }
func (e *escape) heapHole() hole { return e.heapLoc.asHole() }
func (e *escape) discardHole() hole { return e.blankLoc.asHole() }
// walkAll computes the minimal dereferences between all pairs of
// locations.
func (e *Escape) walkAll() {
func (e *escape) walkAll() {
// We use a work queue to keep track of locations that we need
// to visit, and repeatedly walk until we reach a fixed point.
//
@ -1224,8 +1225,8 @@ func (e *Escape) walkAll() {
// happen at most once. So we take Θ(len(e.allLocs)) walks.
// LIFO queue, has enough room for e.allLocs and e.heapLoc.
todo := make([]*EscLocation, 0, len(e.allLocs)+1)
enqueue := func(loc *EscLocation) {
todo := make([]*location, 0, len(e.allLocs)+1)
enqueue := func(loc *location) {
if !loc.queued {
todo = append(todo, loc)
loc.queued = true
@ -1250,7 +1251,7 @@ func (e *Escape) walkAll() {
// walkOne computes the minimal number of dereferences from root to
// all other locations.
func (e *Escape) walkOne(root *EscLocation, walkgen uint32, enqueue func(*EscLocation)) {
func (e *escape) walkOne(root *location, walkgen uint32, enqueue func(*location)) {
// The data flow graph has negative edges (from addressing
// operations), so we use the Bellman-Ford algorithm. However,
// we don't have to worry about infinite negative cycles since
@ -1260,7 +1261,7 @@ func (e *Escape) walkOne(root *EscLocation, walkgen uint32, enqueue func(*EscLoc
root.derefs = 0
root.dst = nil
todo := []*EscLocation{root} // LIFO queue
todo := []*location{root} // LIFO queue
for len(todo) > 0 {
l := todo[len(todo)-1]
todo = todo[:len(todo)-1]
@ -1341,8 +1342,8 @@ func (e *Escape) walkOne(root *EscLocation, walkgen uint32, enqueue func(*EscLoc
}
// explainPath prints an explanation of how src flows to the walk root.
func (e *Escape) explainPath(root, src *EscLocation) []*logopt.LoggedOpt {
visited := make(map[*EscLocation]bool)
func (e *escape) explainPath(root, src *location) []*logopt.LoggedOpt {
visited := make(map[*location]bool)
pos := base.FmtPos(src.n.Pos())
var explanation []*logopt.LoggedOpt
for {
@ -1371,7 +1372,7 @@ func (e *Escape) explainPath(root, src *EscLocation) []*logopt.LoggedOpt {
return explanation
}
func (e *Escape) explainFlow(pos string, dst, srcloc *EscLocation, derefs int, notes *EscNote, explanation []*logopt.LoggedOpt) []*logopt.LoggedOpt {
func (e *escape) explainFlow(pos string, dst, srcloc *location, derefs int, notes *note, explanation []*logopt.LoggedOpt) []*logopt.LoggedOpt {
ops := "&"
if derefs >= 0 {
ops = strings.Repeat("*", derefs)
@ -1404,7 +1405,7 @@ func (e *Escape) explainFlow(pos string, dst, srcloc *EscLocation, derefs int, n
return explanation
}
func (e *Escape) explainLoc(l *EscLocation) string {
func (e *escape) explainLoc(l *location) string {
if l == &e.heapLoc {
return "{heap}"
}
@ -1420,7 +1421,7 @@ func (e *Escape) explainLoc(l *EscLocation) string {
// outlives reports whether values stored in l may survive beyond
// other's lifetime if stack allocated.
func (e *Escape) outlives(l, other *EscLocation) bool {
func (e *escape) outlives(l, other *location) bool {
// The heap outlives everything.
if l.escapes {
return true
@ -1484,7 +1485,7 @@ func containsClosure(f, c *ir.Func) bool {
}
// leak records that parameter l leaks to sink.
func (l *EscLocation) leakTo(sink *EscLocation, derefs int) {
func (l *location) leakTo(sink *location, derefs int) {
// If sink is a result parameter and we can fit return bits
// into the escape analysis tag, then record a return leak.
if sink.isName(ir.PPARAMOUT) && sink.curfn == l.curfn {
@ -1501,10 +1502,10 @@ func (l *EscLocation) leakTo(sink *EscLocation, derefs int) {
l.paramEsc.AddHeap(derefs)
}
func (e *Escape) finish(fns []*ir.Func) {
func (e *escape) finish(fns []*ir.Func) {
// Record parameter tags for package export data.
for _, fn := range fns {
fn.SetEsc(EscFuncTagged)
fn.SetEsc(escFuncTagged)
narg := 0
for _, fs := range &types.RecvsParams {
@ -1557,47 +1558,47 @@ func (e *Escape) finish(fns []*ir.Func) {
}
}
func (l *EscLocation) isName(c ir.Class) bool {
func (l *location) isName(c ir.Class) bool {
return l.n != nil && l.n.Op() == ir.ONAME && l.n.(*ir.Name).Class_ == c
}
const numEscResults = 7
// An EscLeaks represents a set of assignment flows from a parameter
// An leaks represents a set of assignment flows from a parameter
// to the heap or to any of its function's (first numEscResults)
// result parameters.
type EscLeaks [1 + numEscResults]uint8
type leaks [1 + numEscResults]uint8
// Empty reports whether l is an empty set (i.e., no assignment flows).
func (l EscLeaks) Empty() bool { return l == EscLeaks{} }
func (l leaks) Empty() bool { return l == leaks{} }
// Heap returns the minimum deref count of any assignment flow from l
// to the heap. If no such flows exist, Heap returns -1.
func (l EscLeaks) Heap() int { return l.get(0) }
func (l leaks) Heap() int { return l.get(0) }
// Result returns the minimum deref count of any assignment flow from
// l to its function's i'th result parameter. If no such flows exist,
// Result returns -1.
func (l EscLeaks) Result(i int) int { return l.get(1 + i) }
func (l leaks) Result(i int) int { return l.get(1 + i) }
// AddHeap adds an assignment flow from l to the heap.
func (l *EscLeaks) AddHeap(derefs int) { l.add(0, derefs) }
func (l *leaks) AddHeap(derefs int) { l.add(0, derefs) }
// AddResult adds an assignment flow from l to its function's i'th
// result parameter.
func (l *EscLeaks) AddResult(i, derefs int) { l.add(1+i, derefs) }
func (l *leaks) AddResult(i, derefs int) { l.add(1+i, derefs) }
func (l *EscLeaks) setResult(i, derefs int) { l.set(1+i, derefs) }
func (l *leaks) setResult(i, derefs int) { l.set(1+i, derefs) }
func (l EscLeaks) get(i int) int { return int(l[i]) - 1 }
func (l leaks) get(i int) int { return int(l[i]) - 1 }
func (l *EscLeaks) add(i, derefs int) {
func (l *leaks) add(i, derefs int) {
if old := l.get(i); old < 0 || derefs < old {
l.set(i, derefs)
}
}
func (l *EscLeaks) set(i, derefs int) {
func (l *leaks) set(i, derefs int) {
v := derefs + 1
if v < 0 {
base.Fatalf("invalid derefs count: %v", derefs)
@ -1611,7 +1612,7 @@ func (l *EscLeaks) set(i, derefs int) {
// Optimize removes result flow paths that are equal in length or
// longer than the shortest heap flow path.
func (l *EscLeaks) Optimize() {
func (l *leaks) Optimize() {
// If we have a path to the heap, then there's no use in
// keeping equal or longer paths elsewhere.
if x := l.Heap(); x >= 0 {
@ -1623,10 +1624,10 @@ func (l *EscLeaks) Optimize() {
}
}
var leakTagCache = map[EscLeaks]string{}
var leakTagCache = map[leaks]string{}
// Encode converts l into a binary string for export data.
func (l EscLeaks) Encode() string {
func (l leaks) Encode() string {
if l.Heap() == 0 {
// Space optimization: empty string encodes more
// efficiently in export data.
@ -1645,9 +1646,9 @@ func (l EscLeaks) Encode() string {
return s
}
// ParseLeaks parses a binary string representing an EscLeaks.
func ParseLeaks(s string) EscLeaks {
var l EscLeaks
// parseLeaks parses a binary string representing an EscLeaks.
func parseLeaks(s string) leaks {
var l leaks
if !strings.HasPrefix(s, "esc:") {
l.AddHeap(0)
return l
@ -1656,31 +1657,17 @@ func ParseLeaks(s string) EscLeaks {
return l
}
func escapes(all []ir.Node) {
ir.VisitFuncsBottomUp(all, escapeFuncs)
func Funcs(all []ir.Node) {
ir.VisitFuncsBottomUp(all, Batch)
}
const (
EscFuncUnknown = 0 + iota
EscFuncPlanned
EscFuncStarted
EscFuncTagged
escFuncUnknown = 0 + iota
escFuncPlanned
escFuncStarted
escFuncTagged
)
func min8(a, b int8) int8 {
if a < b {
return a
}
return b
}
func max8(a, b int8) int8 {
if a > b {
return a
}
return b
}
// funcSym returns fn.Nname.Sym if no nils are encountered along the way.
func funcSym(fn *ir.Func) *types.Sym {
if fn == nil || fn.Nname == nil {
@ -1855,9 +1842,9 @@ func mayAffectMemory(n ir.Node) bool {
}
}
// heapAllocReason returns the reason the given Node must be heap
// HeapAllocReason returns the reason the given Node must be heap
// allocated, or the empty string if it doesn't.
func heapAllocReason(n ir.Node) string {
func HeapAllocReason(n ir.Node) string {
if n.Type() == nil {
return ""
}
@ -2064,13 +2051,13 @@ func moveToHeap(n *ir.Name) {
// This special tag is applied to uintptr variables
// that we believe may hold unsafe.Pointers for
// calls into assembly functions.
const unsafeUintptrTag = "unsafe-uintptr"
const UnsafeUintptrNote = "unsafe-uintptr"
// This special tag is applied to uintptr parameters of functions
// marked go:uintptrescapes.
const uintptrEscapesTag = "uintptr-escapes"
const UintptrEscapesNote = "uintptr-escapes"
func (e *Escape) paramTag(fn *ir.Func, narg int, f *types.Field) string {
func (e *escape) paramTag(fn *ir.Func, narg int, f *types.Field) string {
name := func() string {
if f.Sym != nil {
return f.Sym.Name
@ -2089,14 +2076,14 @@ func (e *Escape) paramTag(fn *ir.Func, narg int, f *types.Field) string {
if base.Flag.LowerM != 0 {
base.WarnfAt(f.Pos, "assuming %v is unsafe uintptr", name())
}
return unsafeUintptrTag
return UnsafeUintptrNote
}
if !f.Type.HasPointers() { // don't bother tagging for scalars
return ""
}
var esc EscLeaks
var esc leaks
// External functions are assumed unsafe, unless
// //go:noescape is given before the declaration.
@ -2119,14 +2106,14 @@ func (e *Escape) paramTag(fn *ir.Func, narg int, f *types.Field) string {
if base.Flag.LowerM != 0 {
base.WarnfAt(f.Pos, "marking %v as escaping uintptr", name())
}
return uintptrEscapesTag
return UintptrEscapesNote
}
if f.IsDDD() && f.Type.Elem().IsUintptr() {
// final argument is ...uintptr.
if base.Flag.LowerM != 0 {
base.WarnfAt(f.Pos, "marking %v as escaping ...uintptr", name())
}
return uintptrEscapesTag
return UintptrEscapesNote
}
}
@ -2136,7 +2123,7 @@ func (e *Escape) paramTag(fn *ir.Func, narg int, f *types.Field) string {
// Unnamed parameters are unused and therefore do not escape.
if f.Sym == nil || f.Sym.IsBlank() {
var esc EscLeaks
var esc leaks
return esc.Encode()
}

3
src/cmd/compile/internal/gc/gsubr.go
View File

@ -32,6 +32,7 @@ package gc
import (
"cmd/compile/internal/base"
"cmd/compile/internal/escape"
"cmd/compile/internal/ir"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
@ -141,7 +142,7 @@ func makeABIWrapper(f *ir.Func, wrapperABI obj.ABI) {
ir.CurFunc = fn
typecheck.Stmts(fn.Body)
escapeFuncs([]*ir.Func{fn}, false)
escape.Batch([]*ir.Func{fn}, false)
typecheck.Target.Decls = append(typecheck.Target.Decls, fn)

5
src/cmd/compile/internal/gc/main.go
View File

@ -10,6 +10,7 @@ import (
"bufio"
"bytes"
"cmd/compile/internal/base"
"cmd/compile/internal/escape"
"cmd/compile/internal/inline"
"cmd/compile/internal/ir"
"cmd/compile/internal/logopt"
@ -183,7 +184,7 @@ func Main(archInit func(*Arch)) {
logopt.LogJsonOption(base.Flag.JSON)
}
ir.EscFmt = escFmt
ir.EscFmt = escape.Fmt
ir.IsIntrinsicCall = isIntrinsicCall
inline.SSADumpInline = ssaDumpInline
initSSAEnv()
@ -252,7 +253,7 @@ func Main(archInit func(*Arch)) {
// Large values are also moved off stack in escape analysis;
// because large values may contain pointers, it must happen early.
base.Timer.Start("fe", "escapes")
escapes(typecheck.Target.Decls)
escape.Funcs(typecheck.Target.Decls)
// Collect information for go:nowritebarrierrec
// checking. This must happen before transformclosure.

3
src/cmd/compile/internal/gc/order.go
View File

@ -6,6 +6,7 @@ package gc
import (
"cmd/compile/internal/base"
"cmd/compile/internal/escape"
"cmd/compile/internal/ir"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
@ -521,7 +522,7 @@ func (o *Order) call(nn ir.Node) {
// Check for "unsafe-uintptr" tag provided by escape analysis.
for i, param := range n.X.Type().Params().FieldSlice() {
if param.Note == unsafeUintptrTag || param.Note == uintptrEscapesTag {
if param.Note == escape.UnsafeUintptrNote || param.Note == escape.UintptrEscapesNote {
if arg := n.Args[i]; arg.Op() == ir.OSLICELIT {
arg := arg.(*ir.CompLitExpr)
for _, elt := range arg.List {

14
src/cmd/compile/internal/gc/ssa.go
View File

@ -7396,3 +7396,17 @@ func callTargetLSym(callee *types.Sym, callerLSym *obj.LSym) *obj.LSym {
}
return lsym
}
func min8(a, b int8) int8 {
if a < b {
return a
}
return b
}
func max8(a, b int8) int8 {
if a > b {
return a
}
return b
}

3
src/cmd/compile/internal/gc/subr.go
View File

@ -6,6 +6,7 @@ package gc
import (
"cmd/compile/internal/base"
"cmd/compile/internal/escape"
"cmd/compile/internal/inline"
"cmd/compile/internal/ir"
"cmd/compile/internal/typecheck"
@ -484,7 +485,7 @@ func genwrapper(rcvr *types.Type, method *types.Field, newnam *types.Sym) {
if rcvr.IsPtr() && rcvr.Elem() == method.Type.Recv().Type && rcvr.Elem().Sym() != nil {
inline.InlineCalls(fn)
}
escapeFuncs([]*ir.Func{fn}, false)
escape.Batch([]*ir.Func{fn}, false)
ir.CurFunc = nil
typecheck.Target.Decls = append(typecheck.Target.Decls, fn)

3
src/cmd/compile/internal/gc/walk.go
View File

@ -6,6 +6,7 @@ package gc
import (
"cmd/compile/internal/base"
"cmd/compile/internal/escape"
"cmd/compile/internal/ir"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
@ -1455,7 +1456,7 @@ func walkexpr1(n ir.Node, init *ir.Nodes) ir.Node {
base.Errorf("%v can't be allocated in Go; it is incomplete (or unallocatable)", t.Elem())
}
if n.Esc() == ir.EscNone {
if why := heapAllocReason(n); why != "" {
if why := escape.HeapAllocReason(n); why != "" {
base.Fatalf("%v has EscNone, but %v", n, why)
}
// var arr [r]T