Commit graph

486 commits

Author SHA1 Message Date
Russ Cox
4eaef981b5 [dev.regabi] cmd/compile: add ir.Closure, ir.ClosureRead
Closures are another reference to Funcs,
and it cleans up the code quite a bit to be clear about types.

OCLOSUREVAR is renamed to OCLOSUREREAD to make
clearer that it is unrelated to the list Func.ClosureVars.

Passes buildall w/ toolstash -cmp.

Change-Id: Id0d28df2d4d6e9954e34df7a39ea226995eee937
Reviewed-on: https://go-review.googlesource.com/c/go/+/274098
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-30 18:34:02 +00:00
Russ Cox
e84b27bec5 [dev.regabi] cmd/compile: clean up Name and Func uses
Now that we have specific types for ONAME and ODCLFUNC nodes
(*Name and *Func), use them throughout the compiler to be more
precise about what data is being operated on.

This is a somewhat large CL, but once you start applying the types
in a few places, you end up needing to apply them to many other
places to keep everything type-checking. A lot of code also melts
away as types are added.

Passes buildall w/ toolstash -cmp.

Change-Id: I21dd9b945d701c470332bac5394fca744a5b232d
Reviewed-on: https://go-review.googlesource.com/c/go/+/274097
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-30 18:34:01 +00:00
Russ Cox
862f638a89 [dev.regabi] cmd/compile: make ir.Name the ONAME Node implementation
Before this CL, an ONAME Node was represented by three structs
linked together: a node, a Name, and a Param. Previous CLs removed
OLABEL and OPACK from the set of nodes that knew about Name.
Now Name can be repurposed to *be* the ONAME Node implementation,
replacing three linked structs totaling 152+64+88 = 304 bytes (64-bit)
with a single 232-byte struct.

Many expressions in the code become simpler as well, without having
to use .Param. and sometimes even .Name().
(For a node n where n.Name() != nil, n.Name() == n.(*Name) now.)

Passes buildall w/ toolstash -cmp.

Change-Id: Ie719f1285c05623b9fd2faaa059e5b360a64b3be
Reviewed-on: https://go-review.googlesource.com/c/go/+/274094
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-30 18:33:57 +00:00
Russ Cox
b09dbc6913 [dev.regabi] cmd/compile: remove SetOp(OEMPTY) calls
In preparation for OEMPTY being its own Node implementation,
remove SetOp(OEMPTY) calls that assume other implementations
can be turned into OEMPTY.

Passes buildall w/ toolstash -cmp.

Change-Id: Icac16d12548f35f52a5efa9d09dacf8260f42075
Reviewed-on: https://go-review.googlesource.com/c/go/+/274090
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-30 18:33:52 +00:00
Russ Cox
41f3af9d04 [dev.regabi] cmd/compile: replace *Node type with an interface Node [generated]
The plan is to introduce a Node interface that replaces the old *Node pointer-to-struct.

The previous CL defined an interface INode modeling a *Node.

This CL:
 - Changes all references outside internal/ir to use INode,
   along with many references inside internal/ir as well.
 - Renames Node to node.
 - Renames INode to Node

So now ir.Node is an interface implemented by *ir.node, which is otherwise inaccessible,
and the code outside package ir is now (clearly) using only the interface.

The usual rule is never to redefine an existing name with a new meaning,
so that old code that hasn't been updated gets a "unknown name" error
instead of more mysterious errors or silent misbehavior. That rule would
caution against replacing Node-the-struct with Node-the-interface,
as in this CL, because code that says *Node would now be using a pointer
to an interface. But this CL is being landed at the same time as another that
moves Node from gc to ir. So the net effect is to replace *gc.Node with ir.Node,
which does follow the rule: any lingering references to gc.Node will be told
it's gone, not silently start using pointers to interfaces. So the rule is followed
by the CL sequence, just not this specific CL.

Overall, the loss of inlining caused by using interfaces cuts the compiler speed
by about 6%, a not insignificant amount. However, as we convert the representation
to concrete structs that are not the giant Node over the next weeks, that speed
should come back as more of the compiler starts operating directly on concrete types
and the memory taken up by the graph of Nodes drops due to the more precise
structs. Honestly, I was expecting worse.

% benchstat bench.old bench.new
name                      old time/op       new time/op       delta
Template                        168ms ± 4%        182ms ± 2%   +8.34%  (p=0.000 n=9+9)
Unicode                        72.2ms ±10%       82.5ms ± 6%  +14.38%  (p=0.000 n=9+9)
GoTypes                         563ms ± 8%        598ms ± 2%   +6.14%  (p=0.006 n=9+9)
Compiler                        2.89s ± 4%        3.04s ± 2%   +5.37%  (p=0.000 n=10+9)
SSA                             6.45s ± 4%        7.25s ± 5%  +12.41%  (p=0.000 n=9+10)
Flate                           105ms ± 2%        115ms ± 1%   +9.66%  (p=0.000 n=10+8)
GoParser                        144ms ±10%        152ms ± 2%   +5.79%  (p=0.011 n=9+8)
Reflect                         345ms ± 9%        370ms ± 4%   +7.28%  (p=0.001 n=10+9)
Tar                             149ms ± 9%        161ms ± 5%   +8.05%  (p=0.001 n=10+9)
XML                             190ms ± 3%        209ms ± 2%   +9.54%  (p=0.000 n=9+8)
LinkCompiler                    327ms ± 2%        325ms ± 2%     ~     (p=0.382 n=8+8)
ExternalLinkCompiler            1.77s ± 4%        1.73s ± 6%     ~     (p=0.113 n=9+10)
LinkWithoutDebugCompiler        214ms ± 4%        211ms ± 2%     ~     (p=0.360 n=10+8)
StdCmd                          14.8s ± 3%        15.9s ± 1%   +6.98%  (p=0.000 n=10+9)
[Geo mean]                      480ms             510ms        +6.31%

name                      old user-time/op  new user-time/op  delta
Template                        223ms ± 3%        237ms ± 3%   +6.16%  (p=0.000 n=9+10)
Unicode                         103ms ± 6%        113ms ± 3%   +9.53%  (p=0.000 n=9+9)
GoTypes                         758ms ± 8%        800ms ± 2%   +5.55%  (p=0.003 n=10+9)
Compiler                        3.95s ± 2%        4.12s ± 2%   +4.34%  (p=0.000 n=10+9)
SSA                             9.43s ± 1%        9.74s ± 4%   +3.25%  (p=0.000 n=8+10)
Flate                           132ms ± 2%        141ms ± 2%   +6.89%  (p=0.000 n=9+9)
GoParser                        177ms ± 9%        183ms ± 4%     ~     (p=0.050 n=9+9)
Reflect                         467ms ±10%        495ms ± 7%   +6.17%  (p=0.029 n=10+10)
Tar                             183ms ± 9%        197ms ± 5%   +7.92%  (p=0.001 n=10+10)
XML                             249ms ± 5%        268ms ± 4%   +7.82%  (p=0.000 n=10+9)
LinkCompiler                    544ms ± 5%        544ms ± 6%     ~     (p=0.863 n=9+9)
ExternalLinkCompiler            1.79s ± 4%        1.75s ± 6%     ~     (p=0.075 n=10+10)
LinkWithoutDebugCompiler        248ms ± 6%        246ms ± 2%     ~     (p=0.965 n=10+8)
[Geo mean]                      483ms             504ms        +4.41%

[git-generate]
cd src/cmd/compile/internal/ir
: # We need to do the conversion in multiple steps, so we introduce
: # a temporary type alias that will start out meaning the pointer-to-struct
: # and then change to mean the interface.
rf '
	mv Node OldNode

	add node.go \
		type Node = *OldNode
'

: # It should work to do this ex in ir, but it misses test files, due to a bug in rf.
: # Run the command in gc to handle gc's tests, and then again in ssa for ssa's tests.
cd ../gc
rf '
        ex .  ../arm ../riscv64 ../arm64 ../mips64 ../ppc64 ../mips ../wasm {
                import "cmd/compile/internal/ir"
                *ir.OldNode -> ir.Node
        }
'
cd ../ssa
rf '
        ex {
                import "cmd/compile/internal/ir"
                *ir.OldNode -> ir.Node
        }
'

: # Back in ir, finish conversion clumsily with sed,
: # because type checking and circular aliases do not mix.
cd ../ir
sed -i '' '
	/type Node = \*OldNode/d
	s/\*OldNode/Node/g
	s/^func (n Node)/func (n *OldNode)/
	s/OldNode/node/g
	s/type INode interface/type Node interface/
	s/var _ INode = (Node)(nil)/var _ Node = (*node)(nil)/
' *.go
gofmt -w *.go

sed -i '' '
	s/{Func{}, 136, 248}/{Func{}, 152, 280}/
	s/{Name{}, 32, 56}/{Name{}, 44, 80}/
	s/{Param{}, 24, 48}/{Param{}, 44, 88}/
	s/{node{}, 76, 128}/{node{}, 88, 152}/
' sizeof_test.go

cd ../ssa
sed -i '' '
	s/{LocalSlot{}, 28, 40}/{LocalSlot{}, 32, 48}/
' sizeof_test.go

cd ../gc
sed -i '' 's/\*ir.Node/ir.Node/' mkbuiltin.go

cd ../../../..
go install std cmd
cd cmd/compile
go test -u || go test -u

Change-Id: I196bbe3b648e4701662e4a2bada40bf155e2a553
Reviewed-on: https://go-review.googlesource.com/c/go/+/272935
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 17:30:43 +00:00
Russ Cox
acb4d1cef1 [dev.regabi] cmd/compile: use Node getters and setters [generated]
Now that we have all the getters and setters defined, use them
and unexport all the actual Node fields. This is the next step
toward replacing Node with an interface.

[git-generate]
cd src/cmd/compile/internal/gc
rf '
        ex . ../ir ../ssa {
                import "cmd/compile/internal/ir"
                import "cmd/compile/internal/types"
                import "cmd/internal/src"
                var n, x *ir.Node
                var op ir.Op
                var t *types.Type
                var f *ir.Func
                var m *ir.Name
                var s *types.Sym
                var p src.XPos
                var i int64
                var e uint16
                var nodes ir.Nodes

                n.Op = op    -> n.SetOp(op)
                n.Left = x   -> n.SetLeft(x)
                n.Right = x  -> n.SetRight(x)
                n.Orig = x -> n.SetOrig(x)
                n.Type = t -> n.SetType(t)
                n.Func = f -> n.SetFunc(f)
                n.Name = m -> n.SetName(m)
                n.Sym = s -> n.SetSym(s)
                n.Pos = p -> n.SetPos(p)
                n.Xoffset = i -> n.SetXoffset(i)
                n.Esc = e -> n.SetEsc(e)

                n.Ninit.Append -> n.PtrNinit().Append
                n.Ninit.AppendNodes -> n.PtrNinit().AppendNodes
                n.Ninit.MoveNodes -> n.PtrNinit().MoveNodes
                n.Ninit.Prepend -> n.PtrNinit().Prepend
                n.Ninit.Set -> n.PtrNinit().Set
                n.Ninit.Set1 -> n.PtrNinit().Set1
                n.Ninit.Set2 -> n.PtrNinit().Set2
                n.Ninit.Set3 -> n.PtrNinit().Set3
                &n.Ninit -> n.PtrNinit()
                n.Ninit = nodes -> n.SetNinit(nodes)

                n.Nbody.Append -> n.PtrNbody().Append
                n.Nbody.AppendNodes -> n.PtrNbody().AppendNodes
                n.Nbody.MoveNodes -> n.PtrNbody().MoveNodes
                n.Nbody.Prepend -> n.PtrNbody().Prepend
                n.Nbody.Set -> n.PtrNbody().Set
                n.Nbody.Set1 -> n.PtrNbody().Set1
                n.Nbody.Set2 -> n.PtrNbody().Set2
                n.Nbody.Set3 -> n.PtrNbody().Set3
                &n.Nbody -> n.PtrNbody()
                n.Nbody = nodes -> n.SetNbody(nodes)

                n.List.Append -> n.PtrList().Append
                n.List.AppendNodes -> n.PtrList().AppendNodes
                n.List.MoveNodes -> n.PtrList().MoveNodes
                n.List.Prepend -> n.PtrList().Prepend
                n.List.Set -> n.PtrList().Set
                n.List.Set1 -> n.PtrList().Set1
                n.List.Set2 -> n.PtrList().Set2
                n.List.Set3 -> n.PtrList().Set3
                &n.List -> n.PtrList()
                n.List = nodes -> n.SetList(nodes)

                n.Rlist.Append -> n.PtrRlist().Append
                n.Rlist.AppendNodes -> n.PtrRlist().AppendNodes
                n.Rlist.MoveNodes -> n.PtrRlist().MoveNodes
                n.Rlist.Prepend -> n.PtrRlist().Prepend
                n.Rlist.Set -> n.PtrRlist().Set
                n.Rlist.Set1 -> n.PtrRlist().Set1
                n.Rlist.Set2 -> n.PtrRlist().Set2
                n.Rlist.Set3 -> n.PtrRlist().Set3
                &n.Rlist -> n.PtrRlist()
                n.Rlist = nodes -> n.SetRlist(nodes)
        }
        ex . ../ir ../ssa {
                import "cmd/compile/internal/ir"

                var n *ir.Node
                n.Op         -> n.GetOp()
                n.Left       -> n.GetLeft()
                n.Right      -> n.GetRight()
                n.Orig -> n.GetOrig()
                n.Type -> n.GetType()
                n.Func -> n.GetFunc()
                n.Name -> n.GetName()
                n.Sym -> n.GetSym()
                n.Pos -> n.GetPos()
                n.Xoffset -> n.GetXoffset()
                n.Esc -> n.GetEsc()

                avoid (*ir.Node).PtrNinit
                avoid (*ir.Node).PtrNbody
                avoid (*ir.Node).PtrList
                avoid (*ir.Node).PtrRlist

                n.Ninit -> n.GetNinit()
                n.Nbody -> n.GetNbody()
                n.List -> n.GetList()
                n.Rlist -> n.GetRlist()
        }
'

cd ../ir
rf '
        mv Node.Op Node.op
        mv Node.GetOp Node.Op

        mv Node.Left Node.left
        mv Node.GetLeft Node.Left

        mv Node.Right Node.right
        mv Node.GetRight Node.Right

        mv Node.Orig Node.orig
        mv Node.GetOrig Node.Orig

        mv Node.Type Node.typ
        mv Node.GetType Node.Type

        mv Node.Func Node.fn
        mv Node.GetFunc Node.Func

        mv Node.Name Node.name
        mv Node.GetName Node.Name

        # All uses are in other Node methods already.
        mv Node.E Node.e

        mv Node.Sym Node.sym
        mv Node.GetSym Node.Sym

        mv Node.Pos Node.pos
        mv Node.GetPos Node.Pos

        mv Node.Esc Node.esc
        mv Node.GetEsc Node.Esc

	# While we are here, rename Xoffset to more idiomatic Offset.
        mv Node.Xoffset Node.offset
        mv Node.GetXoffset Node.Offset
	mv Node.SetXoffset Node.SetOffset

        # While we are here, rename Ninit, Nbody to more idiomatic Init, Body.
        mv Node.Ninit Node.init
        mv Node.GetNinit Node.Init
        mv Node.PtrNinit Node.PtrInit
        mv Node.SetNinit Node.SetInit
        mv Node.Nbody Node.body
        mv Node.GetNbody Node.Body
        mv Node.PtrNbody Node.PtrBody
        mv Node.SetNbody Node.SetBody
        mv Node.List Node.list
        mv Node.GetList Node.List
        mv Node.Rlist Node.rlist
        mv Node.GetRlist Node.Rlist

        # Unexport these
        mv Node.SetHasOpt Node.setHasOpt
        mv Node.SetHasVal Node.setHasVal
'

Change-Id: I9894f633375c5237a29b6d6d7b89ba181b56ca3a
Reviewed-on: https://go-review.googlesource.com/c/go/+/273009
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 17:30:39 +00:00
Russ Cox
84e2bd611f [dev.regabi] cmd/compile: introduce cmd/compile/internal/ir [generated]
If we want to break up package gc at all, we will need to move
the compiler IR it defines into a separate package that can be
imported by packages that gc itself imports. This CL does that.
It also removes the TINT8 etc aliases so that all code is clear
about which package things are coming from.

This CL is automatically generated by the script below.
See the comments in the script for details about the changes.

[git-generate]
cd src/cmd/compile/internal/gc

rf '
        # These names were never fully qualified
        # when the types package was added.
        # Do it now, to avoid confusion about where they live.
        inline -rm \
                Txxx \
                TINT8 \
                TUINT8 \
                TINT16 \
                TUINT16 \
                TINT32 \
                TUINT32 \
                TINT64 \
                TUINT64 \
                TINT \
                TUINT \
                TUINTPTR \
                TCOMPLEX64 \
                TCOMPLEX128 \
                TFLOAT32 \
                TFLOAT64 \
                TBOOL \
                TPTR \
                TFUNC \
                TSLICE \
                TARRAY \
                TSTRUCT \
                TCHAN \
                TMAP \
                TINTER \
                TFORW \
                TANY \
                TSTRING \
                TUNSAFEPTR \
                TIDEAL \
                TNIL \
                TBLANK \
                TFUNCARGS \
                TCHANARGS \
                NTYPE \
                BADWIDTH

        # esc.go and escape.go do not need to be split.
        # Append esc.go onto the end of escape.go.
        mv esc.go escape.go

        # Pull out the type format installation from func Main,
        # so it can be carried into package ir.
        mv Main:/Sconv.=/-0,/TypeLinkSym/-1 InstallTypeFormats

        # Names that need to be exported for use by code left in gc.
        mv Isconst IsConst
        mv asNode AsNode
        mv asNodes AsNodes
        mv asTypesNode AsTypesNode
        mv basicnames BasicTypeNames
        mv builtinpkg BuiltinPkg
        mv consttype ConstType
        mv dumplist DumpList
        mv fdumplist FDumpList
        mv fmtMode FmtMode
        mv goopnames OpNames
        mv inspect Inspect
        mv inspectList InspectList
        mv localpkg LocalPkg
        mv nblank BlankNode
        mv numImport NumImport
        mv opprec OpPrec
        mv origSym OrigSym
        mv stmtwithinit StmtWithInit
        mv dump DumpAny
        mv fdump FDumpAny
        mv nod Nod
        mv nodl NodAt
        mv newname NewName
        mv newnamel NewNameAt
        mv assertRepresents AssertValidTypeForConst
        mv represents ValidTypeForConst
        mv nodlit NewLiteral

        # Types and fields that need to be exported for use by gc.
        mv nowritebarrierrecCallSym SymAndPos
        mv SymAndPos.lineno SymAndPos.Pos
        mv SymAndPos.target SymAndPos.Sym

        mv Func.lsym Func.LSym
        mv Func.setWBPos Func.SetWBPos
        mv Func.numReturns Func.NumReturns
        mv Func.numDefers Func.NumDefers
        mv Func.nwbrCalls Func.NWBRCalls

        # initLSym is an algorithm left behind in gc,
        # not an operation on Func itself.
        mv Func.initLSym initLSym

        mv nodeQueue NodeQueue
        mv NodeQueue.empty NodeQueue.Empty
        mv NodeQueue.popLeft NodeQueue.PopLeft
        mv NodeQueue.pushRight NodeQueue.PushRight

        # Many methods on Node are actually algorithms that
        # would apply to any node implementation.
        # Those become plain functions.
        mv Node.funcname FuncName
        mv Node.isBlank IsBlank
        mv Node.isGoConst isGoConst
        mv Node.isNil IsNil
        mv Node.isParamHeapCopy isParamHeapCopy
        mv Node.isParamStackCopy isParamStackCopy
        mv Node.isSimpleName isSimpleName
        mv Node.mayBeShared MayBeShared
        mv Node.pkgFuncName PkgFuncName
        mv Node.backingArrayPtrLen backingArrayPtrLen
        mv Node.isterminating isTermNode
        mv Node.labeledControl labeledControl
        mv Nodes.isterminating isTermNodes
        mv Nodes.sigerr fmtSignature
        mv Node.MethodName methodExprName
        mv Node.MethodFunc methodExprFunc
        mv Node.IsMethod IsMethod

        # Every node will need to implement RawCopy;
        # Copy and SepCopy algorithms will use it.
        mv Node.rawcopy Node.RawCopy
        mv Node.copy Copy
        mv Node.sepcopy SepCopy

        # Extract Node.Format method body into func FmtNode,
        # but leave method wrapper behind.
        mv Node.Format:0,$ FmtNode

        # Formatting helpers that will apply to all node implementations.
        mv Node.Line Line
        mv Node.exprfmt exprFmt
        mv Node.jconv jconvFmt
        mv Node.modeString modeString
        mv Node.nconv nconvFmt
        mv Node.nodedump nodeDumpFmt
        mv Node.nodefmt nodeFmt
        mv Node.stmtfmt stmtFmt

	# Constant support needed for code moving to ir.
        mv okforconst OKForConst
        mv vconv FmtConst
        mv int64Val Int64Val
        mv float64Val Float64Val
        mv Node.ValueInterface ConstValue

        # Organize code into files.
        mv LocalPkg BuiltinPkg ir.go
        mv NumImport InstallTypeFormats Line fmt.go
        mv syntax.go Nod NodAt NewNameAt Class Pxxx PragmaFlag Nointerface SymAndPos \
                AsNode AsTypesNode BlankNode OrigSym \
                Node.SliceBounds Node.SetSliceBounds Op.IsSlice3 \
                IsConst Node.Int64Val Node.CanInt64 Node.Uint64Val Node.BoolVal Node.StringVal \
                Node.RawCopy SepCopy Copy \
                IsNil IsBlank IsMethod \
                Node.Typ Node.StorageClass node.go
        mv ConstType ConstValue Int64Val Float64Val AssertValidTypeForConst ValidTypeForConst NewLiteral idealType OKForConst val.go

        # Move files to new ir package.
        mv bitset.go class_string.go dump.go fmt.go \
                ir.go node.go op_string.go val.go \
                sizeof_test.go cmd/compile/internal/ir
'

: # fix mkbuiltin.go to generate the changes made to builtin.go during rf
sed -i '' '
        s/\[T/[types.T/g
        s/\*Node/*ir.Node/g
        /internal\/types/c \
                fmt.Fprintln(&b, `import (`) \
                fmt.Fprintln(&b, `      "cmd/compile/internal/ir"`) \
                fmt.Fprintln(&b, `      "cmd/compile/internal/types"`) \
                fmt.Fprintln(&b, `)`)
' mkbuiltin.go
gofmt -w mkbuiltin.go

: # update cmd/dist to add internal/ir
cd ../../../dist
sed -i '' '/compile.internal.gc/a\
        "cmd/compile/internal/ir",
' buildtool.go
gofmt -w buildtool.go

: # update cmd/compile TestFormats
cd ../..
go install std cmd
cd cmd/compile
go test -u || go test  # first one updates but fails; second passes

Change-Id: I5f7caf6b20629b51970279e81231a3574d5b51db
Reviewed-on: https://go-review.googlesource.com/c/go/+/273008
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 16:53:33 +00:00
Russ Cox
26b66fd60b [dev.regabi] cmd/compile: introduce cmd/compile/internal/base [generated]
Move Flag, Debug, Ctxt, Exit, and error messages to
new package cmd/compile/internal/base.

These are the core functionality that everything in gc uses
and which otherwise prevent splitting any other code
out of gc into different packages.

A minor milestone: the compiler source code
no longer contains the string "yy".

[git-generate]
cd src/cmd/compile/internal/gc
rf '
        mv atExit AtExit
        mv Ctxt atExitFuncs AtExit Exit base.go

        mv lineno Pos
        mv linestr FmtPos
        mv flusherrors FlushErrors
        mv yyerror Errorf
        mv yyerrorl ErrorfAt
        mv yyerrorv ErrorfVers
        mv noder.yyerrorpos noder.errorAt
        mv Warnl WarnfAt
        mv errorexit ErrorExit

        mv base.go debug.go flag.go print.go cmd/compile/internal/base
'

: # update comments
sed -i '' 's/yyerrorl/ErrorfAt/g; s/yyerror/Errorf/g' *.go

: # bootstrap.go is not built by default so invisible to rf
sed -i '' 's/Fatalf/base.Fatalf/' bootstrap.go
goimports -w bootstrap.go

: # update cmd/dist to add internal/base
cd ../../../dist
sed -i '' '/internal.amd64/a\
	"cmd/compile/internal/base",
' buildtool.go
gofmt -w buildtool.go

Change-Id: I59903c7084222d6eaee38823fd222159ba24a31a
Reviewed-on: https://go-review.googlesource.com/c/go/+/272250
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 16:39:54 +00:00
Russ Cox
3c240f5d17 [dev.regabi] cmd/compile: clean up debug flag (-d) handling [generated]
The debug table is not as haphazard as flags, but there are still
a few mismatches between command-line names and variable names.
This CL moves them all into a consistent home (var Debug, like var Flag).

Code updated automatically using the rf command below.
A followup CL will make a few manual cleanups, leaving this CL
completely automated and easier to regenerate during merge
conflicts.

[git-generate]
cd src/cmd/compile/internal/gc
rf '
	add main.go var Debug struct{}
	mv Debug_append Debug.Append
	mv Debug_checkptr Debug.Checkptr
	mv Debug_closure Debug.Closure
	mv Debug_compilelater Debug.CompileLater
	mv disable_checknil Debug.DisableNil
	mv debug_dclstack Debug.DclStack
	mv Debug_gcprog Debug.GCProg
	mv Debug_libfuzzer Debug.Libfuzzer
	mv Debug_checknil Debug.Nil
	mv Debug_panic Debug.Panic
	mv Debug_slice Debug.Slice
	mv Debug_typeassert Debug.TypeAssert
	mv Debug_wb Debug.WB
	mv Debug_export Debug.Export
	mv Debug_pctab Debug.PCTab
	mv Debug_locationlist Debug.LocationLists
	mv Debug_typecheckinl Debug.TypecheckInl
	mv Debug_gendwarfinl Debug.DwarfInl
	mv Debug_softfloat Debug.SoftFloat
	mv Debug_defer Debug.Defer
	mv Debug_dumpptrs Debug.DumpPtrs

	mv flag.go:/parse.-d/-1,/unknown.debug/+2 parseDebug

	mv debugtab Debug parseDebug \
		debugHelpHeader debugHelpFooter \
		debug.go

	# Remove //go:generate line copied from main.go
	rm debug.go:/go:generate/-+
'

Change-Id: I625761ca5659be4052f7161a83baa00df75cca91
Reviewed-on: https://go-review.googlesource.com/c/go/+/272246
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 16:39:42 +00:00
Russ Cox
18573aea3c [dev.regabi] cmd/compile: clean up flag handling [generated]
The flag values have grown fairly haphazard, with no organization
or even common naming convention. This CL moves all flag values
into the Flag struct (formerly misnamed Debug), except for a few
that live in Ctxt fields instead.

This CL is entirely automated changes.
A followup CL will make a few manual cleanups, leaving this CL
completely automated and easier to regenerate during merge
conflicts.

Cleaning up flags is necessary because the printing routines
look at some of them, and the printing routines need to move
out of package gc to a new package shared by gc and any
other packages that split out of gc.

[git-generate]

cd src/cmd/compile/internal/gc
rf '
	mv Debug Flag
	mv DebugFlags Flags
	mv Flags.e Flags.LowerE
	mv Flags.h Flags.LowerH
	mv Flags.j Flags.LowerJ
	mv Flags.l Flags.LowerL
	mv Flags.m Flags.LowerM
	mv Flags.r Flags.LowerR
	mv Flags.w Flags.LowerW
	mv Flags.P Flags.Percent
	mv compiling_runtime Flag.CompilingRuntime
	mv compiling_std Flag.Std
	mv localimport Flag.D
	mv asmhdr Flag.AsmHdr
	mv buildid Flag.BuildID
	mv nBackendWorkers Flag.LowerC
	mv pure_go Flag.Complete
	mv debugstr Flag.LowerD
	mv flagDWARF Flag.Dwarf
	mv genDwarfInline Flag.GenDwarfInl
	mv flag_installsuffix Flag.InstallSuffix
	mv flag_lang Flag.Lang
	mv linkobj Flag.LinkObj
	mv debuglive Flag.Live
	mv flag_msan Flag.MSan
	mv nolocalimports Flag.NoLocalImports
	mv outfile Flag.LowerO
	mv myimportpath Ctxt.Pkgpath
	mv writearchive Flag.Pack
	mv flag_race Flag.Race
	mv spectre Flag.Spectre
	mv trace Flag.LowerT
	mv pathPrefix Flag.TrimPath
	mv Debug_vlog Ctxt.Debugvlog
	mv use_writebarrier Flag.WB
	mv Main.flag_shared Flag.Shared
	mv Main.flag_dynlink Flag.Dynlink
	mv Main.goversion Flag.GoVersion
	mv Main.symabisPath Flag.SymABIs
	mv cpuprofile Flag.CPUProfile
	mv memprofile Flag.MemProfile
	mv traceprofile Flag.TraceProfile
	mv blockprofile Flag.BlockProfile
	mv mutexprofile Flag.MutexProfile
	mv benchfile Flag.Bench
	mv Main.smallFrames Flag.SmallFrames
	mv Main.jsonLogOpt Flag.JSON

	add Flag:$ \
		Cfg struct{}
	mv embedCfg Flag.Cfg.Embed
	mv idirs Flag.Cfg.ImportDirs
	mv importMap Flag.Cfg.ImportMap
	mv packageFile Flag.Cfg.PackageFile
	mv spectreIndex Flag.Cfg.SpectreIndex

	mv addidir addImportDir

	mv main.go:/Wasm/-0,/ssaDump/-3 ParseFlags

	mv usage Flag Flags ParseFlags \
		concurrentFlagOk concurrentBackendAllowed \
		addImportDir addImportMap \
		readImportCfg readEmbedCfg \
		flag.go

	# Remove //go:generate line copied from main.go
	# along with two self-assignments from the merge.
	rm flag.go:/go:generate/-+ \
		flag.go:/Ctxt.Pkgpath = Ctxt.Pkgpath/-+ \
		flag.go:/Ctxt.Debugvlog = Ctxt.Debugvlog/-+
'

Change-Id: I10431c15fe7d9f48024d53141d4224d957dbf334
Reviewed-on: https://go-review.googlesource.com/c/go/+/271667
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-25 15:08:55 +00:00
Matthew Dempsky
7d72951229 [dev.regabi] cmd/compile: replace Val with go/constant.Value
This replaces the compiler's legacy constant representation with
go/constant, which is used by go/types. This should ease integrating
with the new go/types-based type checker in the future.

Performance difference is mixed, but there's still room for
improvement.

name                      old time/op       new time/op       delta
Template                        280ms ± 6%        281ms ± 6%    ~     (p=0.488 n=592+587)
Unicode                         132ms ±11%        129ms ±11%  -2.61%  (p=0.000 n=592+591)
GoTypes                         865ms ± 3%        866ms ± 3%  +0.16%  (p=0.019 n=572+577)
Compiler                        3.60s ± 3%        3.60s ± 3%    ~     (p=0.083 n=578+582)
SSA                             8.27s ± 2%        8.28s ± 2%  +0.14%  (p=0.002 n=575+580)
Flate                           177ms ± 8%        176ms ± 8%    ~     (p=0.133 n=580+590)
GoParser                        238ms ± 7%        237ms ± 6%    ~     (p=0.569 n=587+591)
Reflect                         542ms ± 4%        543ms ± 4%    ~     (p=0.064 n=581+579)
Tar                             244ms ± 6%        244ms ± 6%    ~     (p=0.880 n=586+584)
XML                             322ms ± 5%        322ms ± 5%    ~     (p=0.449 n=589+590)
LinkCompiler                    454ms ± 6%        453ms ± 6%    ~     (p=0.249 n=585+583)
ExternalLinkCompiler            1.35s ± 4%        1.35s ± 4%    ~     (p=0.968 n=590+588)
LinkWithoutDebugCompiler        279ms ± 7%        280ms ± 7%    ~     (p=0.270 n=589+586)
[Geo mean]                      535ms             534ms       -0.17%

name                      old user-time/op  new user-time/op  delta
Template                        599ms ±22%        602ms ±21%    ~     (p=0.377 n=588+590)
Unicode                         410ms ±43%        376ms ±39%  -8.36%  (p=0.000 n=596+586)
GoTypes                         1.96s ±15%        1.97s ±17%  +0.70%  (p=0.031 n=596+594)
Compiler                        7.47s ± 9%        7.50s ± 8%  +0.38%  (p=0.031 n=591+583)
SSA                             16.2s ± 4%        16.2s ± 5%    ~     (p=0.617 n=531+531)
Flate                           298ms ±25%        292ms ±30%  -2.14%  (p=0.001 n=594+596)
GoParser                        379ms ±20%        381ms ±21%    ~     (p=0.312 n=578+584)
Reflect                         1.24s ±20%        1.25s ±23%  +0.88%  (p=0.031 n=592+596)
Tar                             471ms ±23%        473ms ±21%    ~     (p=0.616 n=593+587)
XML                             674ms ±20%        681ms ±21%  +1.03%  (p=0.050 n=584+587)
LinkCompiler                    842ms ±10%        839ms ±10%    ~     (p=0.074 n=587+590)
ExternalLinkCompiler            1.65s ± 7%        1.65s ± 7%    ~     (p=0.767 n=590+585)
LinkWithoutDebugCompiler        378ms ±11%        379ms ±12%    ~     (p=0.677 n=591+586)
[Geo mean]                      1.02s             1.02s       -0.52%

name                      old alloc/op      new alloc/op      delta
Template                       37.4MB ± 0%       37.4MB ± 0%  +0.06%  (p=0.000 n=589+585)
Unicode                        29.6MB ± 0%       28.6MB ± 0%  -3.11%  (p=0.000 n=574+566)
GoTypes                         120MB ± 0%        120MB ± 0%  -0.01%  (p=0.000 n=594+593)
Compiler                        568MB ± 0%        568MB ± 0%  -0.02%  (p=0.000 n=588+591)
SSA                            1.45GB ± 0%       1.45GB ± 0%  -0.16%  (p=0.000 n=596+592)
Flate                          22.6MB ± 0%       22.5MB ± 0%  -0.36%  (p=0.000 n=593+595)
GoParser                       30.1MB ± 0%       30.1MB ± 0%  -0.01%  (p=0.000 n=590+594)
Reflect                        77.8MB ± 0%       77.8MB ± 0%    ~     (p=0.631 n=584+591)
Tar                            34.1MB ± 0%       34.1MB ± 0%  -0.04%  (p=0.000 n=584+588)
XML                            43.6MB ± 0%       43.6MB ± 0%  +0.07%  (p=0.000 n=593+591)
LinkCompiler                   98.6MB ± 0%       98.6MB ± 0%    ~     (p=0.096 n=590+589)
ExternalLinkCompiler           89.6MB ± 0%       89.6MB ± 0%    ~     (p=0.695 n=590+587)
LinkWithoutDebugCompiler       57.2MB ± 0%       57.2MB ± 0%    ~     (p=0.674 n=590+589)
[Geo mean]                     78.5MB            78.3MB       -0.28%

name                      old allocs/op     new allocs/op     delta
Template                         379k ± 0%         380k ± 0%  +0.33%  (p=0.000 n=593+590)
Unicode                          344k ± 0%         338k ± 0%  -1.67%  (p=0.000 n=594+589)
GoTypes                         1.30M ± 0%        1.31M ± 0%  +0.19%  (p=0.000 n=592+591)
Compiler                        5.40M ± 0%        5.41M ± 0%  +0.23%  (p=0.000 n=587+585)
SSA                             14.2M ± 0%        14.2M ± 0%  +0.08%  (p=0.000 n=594+591)
Flate                            231k ± 0%         230k ± 0%  -0.42%  (p=0.000 n=588+589)
GoParser                         314k ± 0%         315k ± 0%  +0.16%  (p=0.000 n=587+594)
Reflect                          975k ± 0%         976k ± 0%  +0.10%  (p=0.000 n=590+594)
Tar                              344k ± 0%         345k ± 0%  +0.24%  (p=0.000 n=595+590)
XML                              422k ± 0%         424k ± 0%  +0.57%  (p=0.000 n=590+589)
LinkCompiler                     538k ± 0%         538k ± 0%  -0.00%  (p=0.045 n=592+587)
ExternalLinkCompiler             593k ± 0%         593k ± 0%    ~     (p=0.171 n=588+587)
LinkWithoutDebugCompiler         172k ± 0%         172k ± 0%    ~     (p=0.996 n=590+585)
[Geo mean]                       685k              685k       -0.02%

name                      old maxRSS/op     new maxRSS/op     delta
Template                        53.7M ± 8%        53.8M ± 8%    ~     (p=0.666 n=576+574)
Unicode                         54.4M ±12%        55.0M ±10%  +1.15%  (p=0.000 n=591+588)
GoTypes                         95.1M ± 4%        95.1M ± 4%    ~     (p=0.948 n=589+591)
Compiler                         334M ± 6%         334M ± 6%    ~     (p=0.875 n=592+593)
SSA                              792M ± 5%         791M ± 5%    ~     (p=0.067 n=592+591)
Flate                           39.9M ±11%        40.0M ±10%    ~     (p=0.131 n=596+596)
GoParser                        45.2M ±11%        45.3M ±11%    ~     (p=0.353 n=592+590)
Reflect                         76.1M ± 5%        76.2M ± 5%    ~     (p=0.114 n=594+594)
Tar                             49.4M ±10%        49.6M ± 9%  +0.57%  (p=0.015 n=590+593)
XML                             57.4M ± 9%        57.7M ± 8%  +0.67%  (p=0.000 n=592+580)
LinkCompiler                     183M ± 2%         183M ± 2%    ~     (p=0.229 n=587+591)
ExternalLinkCompiler             187M ± 2%         187M ± 3%    ~     (p=0.362 n=571+562)
LinkWithoutDebugCompiler         143M ± 3%         143M ± 3%    ~     (p=0.350 n=584+586)
[Geo mean]                       103M              103M       +0.23%

Passes toolstash-check.

Fixes #4617.

Change-Id: Id4f6759b4afc5e002770091d0d4f6e272ee6cbdd
Reviewed-on: https://go-review.googlesource.com/c/go/+/272654
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-11-25 00:46:44 +00:00
Russ Cox
6826287c6b [dev.regabi] cmd/compile: replace evconst with non-mutating version
evconst is one of the largest sources of Op rewrites,
which prevent separating different kinds of nodes
(in this case, arithmetic nodes and OLITERAL nodes).

The change in swt.go is necessary because otherwise
the syntax graph ends up containing that OLEN expression
multiple times, which violates the invariant that it's a tree
except for ONAME, OLITERAL, and OTYPE nodes.
(Before, the OLEN was overwritten by an OLITERAL, so the
invariant still held, but now that we don't overwrite it,
we need a different copy for each instance.)

Passes toolstash -cmp.

Change-Id: Ia004774ab6852fb384805d0f9f9f234b40842811
Reviewed-on: https://go-review.googlesource.com/c/go/+/272869
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-24 20:58:42 +00:00
Russ Cox
ee6132a698 [dev.regabi] cmd/compile: introduce OMETHEXPR instead of overloading ONAME
A method expression today is an ONAME that has none of the
invariants or properties of other ONAMEs and is always a special case
(hence the Node.IsMethodExpression method).
Remove the special cases by making a separate Op.

Passes toolstash -cmp.

Change-Id: I7667693c9155d5486a6924dbf75ebb59891c4afc
Reviewed-on: https://go-review.googlesource.com/c/go/+/272867
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-24 20:58:29 +00:00
Russ Cox
fd11a32c92 [dev.regabi] cmd/compile: clean up Node.Func
The original meaning of type Func was "extra fields factored out
of a few cases of type Node having to do with functions",
but those specific cases didn't necessarily have any relation.
A typical declared function is represented by an ODCLFUNC Node
at its declaration and an ONAME node at its uses, and both those
have a .Func field, but they are *different* Funcs.
Similarly, a closure is represented both by an OCLOSURE Node for
the value itself and an ODCLFUNC Node for the underlying function
implementing the closure. Those too have *different* Funcs,
and the Func.Closure field in one points to the other and vice versa.
This has led to no end of confusion over the years.

This CL elevates type Func to be the canonical identifier for
a given Go function.

This looks like a trivial CL but in fact is the result of a lot of
scaffolding and rewriting, discarded once the result was achieved, to
separate out the three different kinds of Func nodes into three
separate fields, limited in use to each specific Node type, to
understand which Func fields are used by which Node types and what the
possible overlaps are. There were a few overlaps, most notably around
closures, which led to more fields being added to type Func to keep
them separate even though there is now a single Func instead of two
different ones for each function.

A future CL can and should change Curfn to be a *Func instead of
a *Node, finally eliminating the confusion about whether Curfn
is an ODCLFUNC node (as it is most of the time) or an ONAME node
(as it is when type-checking an inlined function body).

Although sizeof_test.go makes it look like Func is growing by two
words, there are now half as many Funcs in a running compilation,
so the memory footprint has actually been reduced substantially.

Change-Id: I598bd96c95728093dc769a835d48f2154a406a61
Reviewed-on: https://go-review.googlesource.com/c/go/+/272253
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-24 20:58:11 +00:00
Matthew Dempsky
742c05e3bc [dev.regabi] cmd/compile: prep refactoring for switching to go/constant
This CL replaces gc.Ctype (along with its CTINT, etc. constants) with
constant.Kind; renames Val.Ctype to Val.Kind; and replaces a handful
of abstraction-violating patterns that can be readily expressed
differently.

The next commit will actually replace Val with constant.Value.

Passes toolstash-check.

[git-generate]
cd src/cmd/compile/internal/gc

sed -i 's/type Ctype uint8/type Ctype = constant.Kind/' const.go
goimports -w const.go

rf '
inline -rm Ctype
mv Val.Ctype Val.Kind

ex import "go/constant"; \
  CTxxx  -> constant.Unknown; \
  CTINT  -> constant.Int; \
  CTFLT  -> constant.Float; \
  CTCPLX -> constant.Complex; \
  CTBOOL -> constant.Bool; \
  CTSTR  -> constant.String

rm CTxxx CTINT CTFLT CTCPLX CTBOOL CTSTR

ex import "cmd/compile/internal/types"; \
  var t *types.Type; \
  var v, v2 Val; \
  v.U.(*Mpint).Cmp(maxintval[TINT]) > 0 -> doesoverflow(v, types.Types[TINT]); \
  v.U.(*Mpint).Cmp(v2.U.(*Mpint)) > 0 -> compareOp(v, OGT, v2); \
  maxintval[t.Etype].Cmp(maxintval[TUINT]) <= 0 -> t.Size() <= types.Types[TUINT].Size(); \
  maxintval[t.Etype].Cmp(maxintval[TUINT]) >  0 -> t.Size() >  types.Types[TUINT].Size();
'

go test cmd/compile -u

Change-Id: I6c22ec0597508845f88eee639a0d76cbaa66d08f
Reviewed-on: https://go-review.googlesource.com/c/go/+/272653
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-11-24 19:50:09 +00:00
Matthew Dempsky
c767d73227 [dev.regabi] cmd/compile: remove CTRUNE
Since CL 255217, we've been able to rely on types.UntypedRune to
identify untyped rune literals, rather than needing Mpint.Rune /
CTRUNE. This makes way for switching to using go/constant, which
doesn't have a separate notion of rune constants distinct from integer
constants.

Passes toolstash-check.

Change-Id: I319861f4758aeea17345c101b167cb307e706a0e
Reviewed-on: https://go-review.googlesource.com/c/go/+/272652
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-11-24 19:41:59 +00:00
Matthew Dempsky
88a9e2f9ad [dev.regabi] cmd/compile: replace CTNIL with ONIL
Properly speaking, "nil" is a zero value, not a constant. So
go/constant does not have a representation for it. To allow replacing
Val with constant.Value, we split out ONIL separately from OLITERAL so
we can get rid of CTNIL.

Passes toolstash-check.

Change-Id: I4c8e60cae3b3c91bbac43b3b0cf2a4ade028d6cb
Reviewed-on: https://go-review.googlesource.com/c/go/+/272650
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-11-24 19:34:23 +00:00
Russ Cox
357c576878 [dev.regabi] cmd/compile: clean up error API
Prepare for factoring the error API out of this package by
cleaning it up. The doc comments use the intended new names,
which will be introduced in the next CL.

Change-Id: Ie4c8d4262422da32a9a9f750fda42c225b6b42a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/272248
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-11-24 15:07:09 +00:00
Matthew Dempsky
5b0ec1a6ac cmd/compile: fix panic in field tracking logic
Within the frontend, we generally don't guarantee uniqueness of
anonymous types. For example, each struct type literal gets
represented by its own types.Type instance.

However, the field tracking code was using the struct type as a map
key. This broke in golang.org/cl/256457, because that CL started
changing the inlined parameter variables from using the types.Type of
the declared parameter to that of the call site argument. These are
always identical types (e.g., types.Identical would report true), but
they can be different pointer values, causing the map lookup to fail.

The easiest fix is to simply get rid of the map and instead use
Node.Opt for tracking the types.Field. To mitigate against more latent
field tracking failures (e.g., if any other code were to start trying
to use Opt on ODOT/ODOTPTR fields), we store this field
unconditionally. I also expect having the types.Field will be useful
to other frontend code in the future.

Finally, to make it easier to test field tracking without having to
run make.bash with GOEXPERIMENT=fieldtrack, this commit adds a
-d=fieldtrack flag as an alternative way to enable field tracking
within the compiler. See also #42681.

Fixes #42686.

Change-Id: I6923d206d5e2cab1e6798cba36cae96c1eeaea55
Reviewed-on: https://go-review.googlesource.com/c/go/+/271217
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-11-18 22:12:57 +00:00
Rémy Oudompheng
c1afbf69c7 cmd/compile: use magic multiply for unsigned values less than 1<<16 on 32-bit architectures
This is done by decomposing the number to be divided in 32-bit
components and using the 32-bit magic multiply. For the lowering to be
effective the constant must fit in 16 bits.

On ARM the expression n / 5 compiles to 25 instructions.

Benchmark for GOARCH=arm (Cortex-A53)

name                     old time/op  new time/op  delta
DivconstU64/3-6          1.19µs ± 0%  0.03µs ± 1%  -97.40%  (p=0.000 n=9+9)
DivconstU64/5-6          1.18µs ± 1%  0.03µs ± 1%  -97.38%  (p=0.000 n=10+8)
DivconstU64/37-6         1.13µs ± 1%  0.04µs ± 1%  -96.51%  (p=0.000 n=10+8)
DivconstU64/1234567-6     852ns ± 0%   901ns ± 1%   +5.73%  (p=0.000 n=8+9)

Benchmark for GOARCH=386 (Haswell)

name                     old time/op  new time/op  delta
DivconstU64/3-4          18.0ns ± 2%   5.6ns ± 1%  -69.06%  (p=0.000 n=10+10)
DivconstU64/5-4          17.8ns ± 1%   5.5ns ± 1%  -68.87%  (p=0.000 n=9+10)
DivconstU64/37-4         17.8ns ± 1%   7.3ns ± 0%  -58.90%  (p=0.000 n=10+10)
DivconstU64/1234567-4    17.5ns ± 1%  16.0ns ± 0%   -8.55%  (p=0.000 n=10+9)

Change-Id: I38a19b4d59093ec021ef2e5241364a3dad4eae73
Reviewed-on: https://go-review.googlesource.com/c/go/+/264683
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
2020-10-29 00:07:35 +00:00
Keith Randall
091257def9 cmd/compile: print pointers to go:notinheap types without converting to unsafe.Pointer
Pretty minor concern, but after auditing the compiler/runtime for
conversions from pointers to go:notinheap types to unsafe.Pointer,
this is the only remaining one I found.

Update #42076

Change-Id: I81d5b893c9ada2fc19a51c2559262f2e9ff71c35
Reviewed-on: https://go-review.googlesource.com/c/go/+/265757
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-27 22:13:30 +00:00
Cuong Manh Le
a19cf510af cmd/compile: defer lowering OANDNOT until SSA
Currently, "x &^ y" gets rewriten into "x & ^y" during walk. It adds
unnecessary complexity to other parts, which must aware about this.

Instead, we can just implement "&^" in the conversion to SSA, so "&^"
can be handled like other binary operators.

However, this CL does not pass toolstash-check. It seems that implements
"&^" in the conversion to SSA causes registers allocation change.

With the parent:

obj: 00212 (.../src/runtime/complex.go:47)    MOVQ    X0, AX
obj: 00213 (.../src/runtime/complex.go:47)    BTRQ    $63, AX
obj: 00214 (.../src/runtime/complex.go:47)    MOVQ    "".n(SP), CX
obj: 00215 (.../src/runtime/complex.go:47)    MOVQ    $-9223372036854775808, DX
obj: 00216 (.../src/runtime/complex.go:47)    ANDQ    DX, CX
obj: 00217 (.../src/runtime/complex.go:47)    ORQ AX, CX

With this CL:

obj: 00212 (.../src/runtime/complex.go:47)    MOVQ    X0, AX
obj: 00213 (.../src/runtime/complex.go:47)    BTRQ    $63, AX
obj: 00214 (.../src/runtime/complex.go:47)    MOVQ    $-9223372036854775808, CX
obj: 00215 (.../src/runtime/complex.go:47)    MOVQ    "".n(SP), DX
obj: 00216 (.../src/runtime/complex.go:47)    ANDQ    CX, DX
obj: 00217 (.../src/runtime/complex.go:47)    ORQ AX, DX

Change-Id: I80acf8496a91be4804fb7ef3df04c19baae2754c
Reviewed-on: https://go-review.googlesource.com/c/go/+/264660
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-27 03:11:45 +00:00
Alberto Donizetti
3bac5faa4a cmd/compile: make gc debug flags collector a struct
gc debug flags are currently stored in a 256-long array, that is then
addressed using the ASCII numeric value of the flag itself (a quirk
inherited from the old C compiler). It is also a little wasteful,
since we only define 16 flags, and the other 240 array elements are
always empty.

This change makes Debug a struct, which also provides static checking
that we're not referencing flags that does not exist.

Change-Id: I2f0dfef2529325514b3398cf78635543cdf48fe0
Reviewed-on: https://go-review.googlesource.com/c/go/+/263539
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-22 09:33:46 +00:00
Matthew Dempsky
76a615b20a cmd/compile: fix defer/go calls to variadic unsafe-uintptr functions
Before generating wrapper function, turn any f(a, b, []T{c, d, e}...)
calls back into f(a, b, c, d, e). This allows the existing code for
recognizing and specially handling unsafe.Pointer->uintptr conversions
to correctly handle variadic arguments too.

Fixes #41460.

Change-Id: I0a1255abdd1bd5dafd3e89547aedd4aec878394c
Reviewed-on: https://go-review.googlesource.com/c/go/+/263297
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-10-17 21:30:53 +00:00
Alberto Donizetti
e2931612b0 cmd/compile: rename strlit, Bool, and Int64 *Node accessors
The Node type has shortcuts to access bool and int Values:

  func (n *Node) Int64() int64
    for n.Val().U.(*Mpint).Int64()

  func (n *Node) Bool() bool
    for n.Val().U.(bool)

I was convinced we didn't have one for string literal nodes, until I
noticed that we do, it's just called strlit, it's not a method, and
it's later in the file:

  func strlit(n *Node) string

This change, for consistency:
- Renames strlit to StringVal and makes it a *Node method
- Renames Bool and Int64 to BoolVal and Int64Val
- Moves StringVal near the other two

Change-Id: I18e635384c35eb3a238fd52b1ccd322b1a74d733
Reviewed-on: https://go-review.googlesource.com/c/go/+/261361
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-14 08:00:39 +00:00
Matthew Dempsky
85bb4294c0 cmd/compile: fix and improve alias detection
"aliased" is the function responsible for detecting whether we can
turn "a, b = x, y" into just "a = x; b = y", or we need to pre-compute
y and save it in a temporary variable because it might depend on a.

It currently has two issues:

1. It suboptimally treats assignments to blank as writes to heap
   memory. Users generally won't write "_, b = x, y" directly, but it
   comes up a lot in generated code within the compiler.

   This CL changes it to ignore blank assignments.

2. When deciding whether the assigned variable might be referenced by
   pointers, it mistakenly checks Class() and Name.Addrtaken() on "n"
   (the *value* expression being assigned) rather than "a" (the
   destination expression).

   It doesn't appear to result in correctness issues (i.e.,
   incorrectly reporting no aliasing when there is potential aliasing),
   due to all the (overly conservative) rewrite passes before code
   reaches here. But it generates unnecessary code and could have
   correctness issues if we improve those other passes to be more
   aggressive.

   This CL fixes the misuse of "n" for "a" by renaming the variables
   to "r" and "l", respectively, to make their meaning clearer.

Improving these two cases shaves 4.6kB of text from cmd/go, and 93kB
from k8s.io/kubernetes/cmd/kubelet:

       text	   data	    bss	    dec	    hex	filename
    9732136	 290072	 231552	10253760	 9c75c0	go.before
    9727542	 290072	 231552	10249166	 9c63ce	go.after
    97977637	1007051	 301344	99286032	5eafc10	kubelet.before
    97884549	1007051	 301344	99192944	5e99070	kubelet.after

While here, this CL also collapses "memwrite" and "varwrite" into a
single variable. Logically, they're detecting the same thing: are we
assigning to a memory location that a pointer might alias. There's no
need for two variables.

Updates #6853.
Updates #23017.

Change-Id: I5a307b8e20bcd2196e85c55eb025d3f01e303008
Reviewed-on: https://go-review.googlesource.com/c/go/+/261677
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2020-10-13 20:44:46 +00:00
Alberto Donizetti
095e0f48a1 cmd/compile: change mustHeapAlloc to return a reason why
This change renames mustHeapAlloc to heapAllocReason, and changes it
to return the reason why the argument must escape, so we don't have to
re-deduce it in its callers just to print the escape reason. It also
embeds isSmallMakeSlice body in heapAllocReason, since the former was
only used by the latter, and deletes isSmallMakeSlice.

An outdated TODO to remove smallintconst, which the TODO claimed was
only used in one place, was also removed, since grepping shows we
currently call smallintconst in 11 different places.

Change-Id: I0bd11bf29b92c4126f5bb455877ff73217d5a155
Reviewed-on: https://go-review.googlesource.com/c/go/+/258678
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-03 13:02:20 +00:00
Cherry Zhang
39dde09126 cmd/link: retain only used interface methods
Currently, in the linker's deadcode pass, when an interface type
is live, the linker thinks all its methods are live, and uses
them to match methods on concrete types. The interface method may
never be used, though.

This CL changes it to only keep used interface methods, for
matching concrete type methods. To do that, when an interface
method is used, the compiler generates a mark relocation. The
linker uses the marker relocations to mark used interface
methods, and only the used ones.

binary size    before      after
cmd/compile   18887400   18812200
cmd/go        13470652   13470492

Change-Id: I3cfd9df4a53783330ba87735853f2a0ec3c42802
Reviewed-on: https://go-review.googlesource.com/c/go/+/256798
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
2020-09-29 16:30:26 +00:00
Cherry Zhang
af18bce87c cmd/link: consider interface conversions only in reachable code
The linker prunes methods that are not directly reachable if the
receiver type is never converted to interface. Currently, this
"never" is too strong: it is invalidated even if the interface
conversion is in an unreachable function. This CL improves it by
only considering interface conversions in reachable code. To do
that, we introduce a marker relocation R_USEIFACE, which marks
the target symbol as UsedInIface if the source symbol is reached.

binary size    before      after
cmd/compile   18897528   18887400
cmd/go        13607372   13470652

Change-Id: I66c6b69eeff9ae02d84d2e6f2bc7f1b29dd53910
Reviewed-on: https://go-review.googlesource.com/c/go/+/256797
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-09-28 21:30:01 +00:00
Matthew Dempsky
ddd35f8d71 cmd/compile: more comprehensive tests for #24991
The revised test now checks that unsafe-uintptr correctly works for
variadic uintptr parameters too, and the CL corrects the code so this
code compiles again.

The pointers are still not kept alive properly. That will be fixed by
a followup CL. But this CL at least allows programs not affected by
that to build again.

Updates #24991.
Updates #41460.

Change-Id: If4c39167b6055e602213fb7522c4f527c43ebda9
Reviewed-on: https://go-review.googlesource.com/c/go/+/255877
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
2020-09-18 05:12:59 +00:00
Keith Randall
37f261010f cmd/compile: make go:notinheap error message friendlier for cgo
Update #40954

Change-Id: Ifaab7349631ccb12fc892882bbdf7f0ebf3d845f
Reviewed-on: https://go-review.googlesource.com/c/go/+/251158
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Keith Randall <khr@golang.org>
2020-09-16 17:28:13 +00:00
Martin Möhrmann
790fa1c546 cmd/compile: unify reflect, string and slice copy runtime functions
Use a common runtime slicecopy function to copy strings or slices
into slices. This deduplicates similar code previously used in
reflect.slicecopy and runtime.stringslicecopy.

Change-Id: I09572ff0647a9e12bb5c6989689ce1c43f16b7f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/254658
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2020-09-16 04:37:14 +00:00
Cuong Manh Le
5f1b12bfbe cmd/compile: remove nodeNeedsWrapper flag
CL 254397 attached OVARLIVE nodes to OCALLxxx nodes Nbody.

The NeedsWrapper flag is now redundant with n.Nbody.Len() > 0
condition, so use that condition instead and remove the flag.

Passes toolstash-check.

Change-Id: Iebc3e674d3c0040a876ca4be05025943d2b4fb31
Reviewed-on: https://go-review.googlesource.com/c/go/+/254398
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-09-13 04:35:35 +00:00
Cuong Manh Le
518369601c cmd/compile: add Type.IsUintptr() to detect type is an uintptr
Passes toolstash-check.

Change-Id: I7051d45eafbfd4dea73a3d4b5ea6cff39d76cbc1
Reviewed-on: https://go-review.googlesource.com/c/go/+/253658
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-09-09 08:03:14 +00:00
Cuong Manh Le
9cf88333e8 cmd/compile: consistently use Type.IsUnsafePtr()
Passes toolstash-check.

Change-Id: Iaeae7cc20e26af733642c7c8c7ca0a059e5b07b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/253657
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-09-09 08:03:05 +00:00
Cuong Manh Le
bdb480fd62 cmd/compile: fix mishandling of unsafe-uintptr arguments in go/defer
Currently, the statement:

	go g(uintptr(f()))

gets rewritten into:

	tmp := f()
	newproc(8, g, uintptr(tmp))
	runtime.KeepAlive(tmp)

which doesn't guarantee that tmp is still alive by time the g call is
scheduled to run.

This CL fixes the issue, by wrapping g call in a closure:

	go func(p unsafe.Pointer) {
		g(uintptr(p))
	}(f())

then this will be rewritten into:

	tmp := f()
	go func(p unsafe.Pointer) {
		g(uintptr(p))
		runtime.KeepAlive(p)
	}(tmp)
	runtime.KeepAlive(tmp)  // superfluous, but harmless

So the unsafe.Pointer p will be kept alive at the time g call runs.

Updates #24491

Change-Id: Ic10821251cbb1b0073daec92b82a866c6ebaf567
Reviewed-on: https://go-review.googlesource.com/c/go/+/253457
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-09-09 07:50:01 +00:00
Cuong Manh Le
a4171d85d7 cmd/compile: do not declare func nodes
The primary responsibility of declare() to associate a symbol (Sym) with
a declaration (Node), so "oldname" will work. Function literals are
anonymous, so their symbols does not need to be declared.

Passes toolstash-check.

Change-Id: I739b1054e3953e85fbd74a99148b9cfd7e5a57eb
Reviewed-on: https://go-review.googlesource.com/c/go/+/249078
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-09-03 02:48:11 +00:00
Keith Randall
d9a6bdf7ef cmd/compile: don't allow go:notinheap on the heap or stack
Right now we just prevent such types from being on the heap. This CL
makes it so they cannot appear on the stack either. The distinction
between heap and stack is pretty vague at the language level (e.g. it
is affected by -N), and we don't need the flexibility anyway.

Once go:notinheap types cannot be in either place, we don't need to
consider pointers to such types to be pointers, at least according to
the garbage collector and stack copying. (This is the big win of this
CL, in my opinion.)

The distinction between HasPointers and HasHeapPointer no longer
exists. There is only HasPointers.

This CL is cleanup before possible use of go:notinheap to fix #40954.

Update #13386

Change-Id: Ibd895aadf001c0385078a6d4809c3f374991231a
Reviewed-on: https://go-review.googlesource.com/c/go/+/249917
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-08-25 01:46:05 +00:00
Keith Randall
623652e73f cmd/compile: make Haspointers a method instead of a function
More ergonomic that way. Also change Haspointers to HasPointers
while we are here.

Change-Id: I45bedc294c1a8c2bd01dc14bd04615ae77555375
Reviewed-on: https://go-review.googlesource.com/c/go/+/249959
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-08-23 18:33:55 +00:00
Matthew Dempsky
e94544cf01 cmd/compile: fix checkptr handling of &^
checkptr has code to recognize &^ expressions, but it didn't take into
account that "p &^ x" gets rewritten to "p & ^x" during walk, which
resulted in false positive diagnostics.

This CL changes walkexpr to mark OANDNOT expressions with Implicit
when they're rewritten to OAND, so that walkCheckPtrArithmetic can
still recognize them later.

It would be slightly more idiomatic to instead mark the OBITNOT
expression as Implicit (as it's a compiler-generated Node), but the
OBITNOT expression might get constant folded. It's not worth the extra
complexity/subtlety of relying on n.Right.Orig, so we set Implicit on
the OAND node instead.

To atone for this transgression, I add documentation for nodeImplicit.

Fixes #40917.

Change-Id: I386304171ad299c530e151e5924f179e9a5fd5b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/249477
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-08-20 17:48:29 +00:00
Cherry Zhang
289c238a33 [dev.link] cmd/compile: make read-only static temps content-addressable
For now, we only do this for symbols without relocations.

Mark static temps "local", as they are not referenced across DSO
boundaries. And deduplicating a local symbol and a non-local
symbol can be problematic.

Change-Id: I0a3dc4138aaeea7fd4f326998f32ab6305da8e4b
Reviewed-on: https://go-review.googlesource.com/c/go/+/243141
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
2020-07-20 17:26:05 +00:00
Cherry Zhang
95848fc5c6 [dev.link] cmd/compile, cmd/link: remove dead methods if type is not used in interface
Currently, a method of a reachable type is live if it matches a
method of a reachable interface. In fact, we only need to retain
the method if the type is actually converted to an interface. If
the type is never converted to an interface, there is no way to
call the method through an interface method call (but the type
descriptor could still be used, e.g. in calling
runtime.newobject).

A type can be used in an interface in two ways:
- directly converted to interface. (Any interface counts, as it
  is possible to convert one interface to another.)
- obtained by reflection from a related type (e.g. obtaining an
  interface of T from []T).

For the former, we let the compiler emit a marker on the type
descriptor symbol when it is converted to an interface. In the
linker, we only need to check methods of marked types.

For the latter, when the linker visits a marked type, it needs to
visit all its "child" types as marked (i.e. potentially could be
converted to interface).

This reduces binary size:
cmd/compile	18792016	18706096 (-0.5%)
cmd/go		14120572	13398948 (-5.1%)

Change-Id: I4465c7eeabf575f4dc84017214c610fa05ae31fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/237298
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
2020-06-11 22:32:49 +00:00
Martin Möhrmann
6ed4661807 cmd/compile: optimize make+copy pattern to avoid memclr
match:
 m = make([]T, x); copy(m, s)
for pointer free T and x==len(s) rewrite to:
 m = mallocgc(x*elemsize(T), nil, false); memmove(&m, &s, x*elemsize(T))
otherwise rewrite to:
 m = makeslicecopy([]T, x, s)

This avoids memclear and shading of pointers in the newly created slice
before the copy.

With this CL "s" is only be allowed to bev a variable and not a more
complex expression. This restriction could be lifted in future versions
of this optimization when it can be proven that "s" is not referencing "m".

Triggers 450 times during make.bash..
Reduces go binary size by ~8 kbyte.

name                           old time/op  new time/op  delta
MakeSliceCopy/mallocmove/Byte  71.1ns ± 1%  65.8ns ± 0%  -7.49%  (p=0.000 n=10+9)
MakeSliceCopy/mallocmove/Int   71.2ns ± 1%  66.0ns ± 0%  -7.27%  (p=0.000 n=10+8)
MakeSliceCopy/mallocmove/Ptr    104ns ± 4%    99ns ± 1%  -5.13%  (p=0.000 n=10+10)
MakeSliceCopy/makecopy/Byte    70.3ns ± 0%  68.0ns ± 0%  -3.22%  (p=0.000 n=10+9)
MakeSliceCopy/makecopy/Int     70.3ns ± 0%  68.5ns ± 1%  -2.59%  (p=0.000 n=9+10)
MakeSliceCopy/makecopy/Ptr      102ns ± 0%    99ns ± 1%  -2.97%  (p=0.000 n=9+9)
MakeSliceCopy/nilappend/Byte   75.4ns ± 0%  74.9ns ± 2%  -0.63%  (p=0.015 n=9+9)
MakeSliceCopy/nilappend/Int    75.6ns ± 0%  76.4ns ± 3%    ~     (p=0.245 n=9+10)
MakeSliceCopy/nilappend/Ptr     107ns ± 0%   108ns ± 1%  +0.93%  (p=0.005 n=9+10)

Fixes #26252

Change-Id: Iec553dd1fef6ded16197216a472351c8799a8e71
Reviewed-on: https://go-review.googlesource.com/c/go/+/146719
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-05-07 17:50:24 +00:00
Josh Bleecher Snyder
f4e13b83aa cmd/compile: refactor out eqinterface
Refactor out creating the two Nodes needed to check interface equality.
Preliminary work to other optimizations.

Passes toolstash-check.

Change-Id: Id6b39e8e78f07289193423d0ef905d70826acf89
Reviewed-on: https://go-review.googlesource.com/c/go/+/230206
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-04-27 17:19:27 +00:00
Josh Bleecher Snyder
daae72e88e cmd/compile: refactor out eqstring
Refactor out creating the two Nodes needed to check string equality.
Preliminary work to other optimizations.

Passes toolstash-check.

Change-Id: I72e824dac904e579b8ba9a3669a94fa1471112d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/230204
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-04-27 17:19:07 +00:00
Matthew Dempsky
a44d06d3b4 cmd/compile: use fixVariadicCall in escape analysis
This CL uses fixVariadicCall before escape analyzing function calls.
This has a number of benefits, though also some minor obstacles:

Most notably, it allows us to remove ODDDARG along with the logic
involved in setting it up, manipulating EscHoles, and later copying
its escape analysis flags to the actual slice argument. Instead, we
uniformly handle all variadic calls the same way. (E.g., issue31573.go
is updated because now f() and f(nil...) are handled identically.)

It also allows us to simplify handling of builtins and generic
function calls. Previously handling of calls was hairy enough to
require multiple dispatches on n.Op, whereas now the logic is uniform
enough that we can easily handle it with a single dispatch.

The downside is handling //go:uintptrescapes is now somewhat clumsy.
(It used to be clumsy, but it still is, too.) The proper fix here is
probably to stop using escape analysis tags for //go:uintptrescapes
and unsafe-uintptr, and have an earlier pass responsible for them.

Finally, note that while we now call fixVariadicCall in Escape, we
still have to call it in Order, because we don't (yet) run Escape on
all compiler-generated functions. In particular, the generated "init"
function for initializing package-level variables can contain calls to
variadic functions and isn't escape analyzed.

Passes toolstash-check -race.

Change-Id: I4cdb92a393ac487910aeee58a5cb8c1500eef881
Reviewed-on: https://go-review.googlesource.com/c/go/+/229759
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-04-23 22:02:12 +00:00
Matthew Dempsky
681ba43077 cmd/compile: move fixVariadicCall from walk to order
This CL moves fixVariadicCall from mid-Walk of function calls to
early-Order, in preparation for moving it even earlier in the future.

Notably, rewriting variadic calls this early introduces two
compilation output changes:

1. Previously, Order visited the ODDDARG before the rest of the
arguments list, whereas the natural time to visit it is at the end of
the list (as we visit arguments left-to-right, and the ... argument is
the rightmost one). Changing this ordering permutes the autotmp
allocation order, which in turn permutes autotmp naming and stack
offsets.

2. Previously, Walk separately walked all of the variadic arguments
before walking the entire slice literal, whereas the more natural
thing to do is just walk the entire slice literal. This triggers
slightly different code paths for composite literal construction in
some cases.

Neither of these have semantic impact. They simply mean we're now
compiling f(a,b,c) the same way as we were already compiling
f([]T{a,b,c}...).

Change-Id: I40ccc5725697a116370111ebe746b2639562fe87
Reviewed-on: https://go-review.googlesource.com/c/go/+/229601
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-04-23 18:29:42 +00:00
Matthew Dempsky
9f4dd09bf5 cmd/compile: refactor variadac call desugaring
In mid-Walk, we rewrite calls to variadic functions to use explicit
slice literals; e.g., rewriting f(a,b,c) into f([]T{a,b,c}...).
However, it would be useful to do that rewrite much earlier in the
compiler, so that other compiler passes can be simplified.

This CL refactors the rewrite logic into a new fixVariadicCall
function, which subsequent CLs can more easily move into earlier
compiler passes.

Passes toolstash-check -race.

Change-Id: I408e655f2d3aa00446a2e6accf8765abc3b16a8a
Reviewed-on: https://go-review.googlesource.com/c/go/+/229486
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-04-23 06:24:40 +00:00
Josh Bleecher Snyder
5abf5f831e cmd/compile: clarify Node.NonNil and Node.Bounded
Node.NonNil and Node.Bounded were a bit muddled. This led to #38496.
This change clarifies and documents them.

It also corrects one misuse.
However, since ssa conversion doesn't make full use of the bounded hint,
this correction doesn't change any generated code.
The next change will fix that.

Passes toolstash-check.

Change-Id: I2bcd487a0a4aef5d7f6090e653974fce0dce3b8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/228787
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-04-20 16:35:40 +00:00
Cuong Manh Le
62ccee49d6 cmd/compile: refactor detecting package reflect logic
Passes toolstash-check.

Change-Id: Ie4b1f61528bb183dc66bb6955851a47b2641549c
Reviewed-on: https://go-review.googlesource.com/c/go/+/228859
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-04-20 02:39:16 +00:00