The non-simple, phi-insertion algorithm can leave OpFwdRefs in the SSA
graph unresolved if they're in dead blocks. Normally, these would be
harmlessly removed later during SSA dead-code elimination, but those
passes are omitted for -N builds. And so they reach zcse, where the
Value.Aux is used within a hash map.
This became a problem after golang.org/cl/275788, which added
FwdRefAux to wrap OpFwdRef's ir.Node, and to ensure that it's not
compared for equality / used as a map key.
This CL adds a simple fix: if there are any OpFwdRefs remaining after
resolveFwdRef, then they must be dead code and we can simply replace
them with OpUnknown.
Change-Id: I72e4116d52d3f6441ebb0bf6160906617cd59513
Reviewed-on: https://go-review.googlesource.com/c/go/+/277075
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
OpFwdRef is the only SSA value that needs the ability to store an
arbitrary ir.Node in its Aux field. Every other SSA value always uses
an *ir.Name.
This CL introduces FwdRefAux, which wraps an ir.Node and implements
the ssa.Aux tag interface, so that a subsequent refactoring can change
ir.Node to not implement ssa.Aux.
Passes buildall w/ toolstash -cmp.
Updates #42982.
Change-Id: Id1475b28847579573cd376e82f28761d84cd1c23
Reviewed-on: https://go-review.googlesource.com/c/go/+/275788
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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>
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>
Each URL was manually verified to ensure it did not serve up incorrect
content.
Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Slightly simplifies the code. Made sure to exclude the cases that would
change behavior, such as when the iterated value is a string, when the
index is modified within the body, or when the slice is modified.
Also checked that all the elements are of pointer type, to avoid the
corner case where non-pointer types could be copied by mistake.
Change-Id: Iea64feb2a9a6a4c94ada9ff3ace40ee173505849
Reviewed-on: https://go-review.googlesource.com/100557
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Prioritized the chunks of code with 8 or more levels of indentation.
Basically early breaks/returns and joining nested ifs.
Change-Id: I6817df1303226acf2eb904a29f2db720e4f7427a
Reviewed-on: https://go-review.googlesource.com/55630
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
When package ssa was created, Type was in package gc.
To avoid circular dependencies, we used an interface (ssa.Type)
to represent type information in SSA.
In the Go 1.9 cycle, gri extricated the Type type from package gc.
As a result, we can now use it in package ssa.
Now, instead of package types depending on package ssa,
it is the other way.
This is a more sensible dependency tree,
and helps compiler performance a bit.
Though this is a big CL, most of the changes are
mechanical and uninteresting.
Interesting bits:
* Add new singleton globals to package types for the special
SSA types Memory, Void, Invalid, Flags, and Int128.
* Add two new Types, TSSA for the special types,
and TTUPLE, for SSA tuple types.
ssa.MakeTuple is now types.NewTuple.
* Move type comparison result constants CMPlt, CMPeq, and CMPgt
to package types.
* We had picked the name "types" in our rules for the handy
list of types provided by ssa.Config. That conflicted with
the types package name, so change it to "typ".
* Update the type comparison routine to handle tuples and special
types inline.
* Teach gc/fmt.go how to print special types.
* We can now eliminate ElemTypes in favor of just Elem,
and probably also some other duplicated Type methods
designed to return ssa.Type instead of *types.Type.
* The ssa tests were using their own dummy types,
and they were not particularly careful about types in general.
Of necessity, this CL switches them to use *types.Type;
it does not make them more type-accurate.
Unfortunately, using types.Type means initializing a bit
of the types universe.
This is prime for refactoring and improvement.
This shrinks ssa.Value; it now fits in a smaller size class
on 64 bit systems. This doesn't have a giant impact,
though, since most Values are preallocated in a chunk.
name old alloc/op new alloc/op delta
Template 37.9MB ± 0% 37.7MB ± 0% -0.57% (p=0.000 n=10+8)
Unicode 28.9MB ± 0% 28.7MB ± 0% -0.52% (p=0.000 n=10+10)
GoTypes 110MB ± 0% 109MB ± 0% -0.88% (p=0.000 n=10+10)
Flate 24.7MB ± 0% 24.6MB ± 0% -0.66% (p=0.000 n=10+10)
GoParser 31.1MB ± 0% 30.9MB ± 0% -0.61% (p=0.000 n=10+9)
Reflect 73.9MB ± 0% 73.4MB ± 0% -0.62% (p=0.000 n=10+8)
Tar 25.8MB ± 0% 25.6MB ± 0% -0.77% (p=0.000 n=9+10)
XML 41.2MB ± 0% 40.9MB ± 0% -0.80% (p=0.000 n=10+10)
[Geo mean] 40.5MB 40.3MB -0.68%
name old allocs/op new allocs/op delta
Template 385k ± 0% 386k ± 0% ~ (p=0.356 n=10+9)
Unicode 343k ± 1% 344k ± 0% ~ (p=0.481 n=10+10)
GoTypes 1.16M ± 0% 1.16M ± 0% -0.16% (p=0.004 n=10+10)
Flate 238k ± 1% 238k ± 1% ~ (p=0.853 n=10+10)
GoParser 320k ± 0% 320k ± 0% ~ (p=0.720 n=10+9)
Reflect 957k ± 0% 957k ± 0% ~ (p=0.460 n=10+8)
Tar 252k ± 0% 252k ± 0% ~ (p=0.133 n=9+10)
XML 400k ± 0% 400k ± 0% ~ (p=0.796 n=10+10)
[Geo mean] 428k 428k -0.01%
Removing all the interface calls helps non-trivially with CPU, though.
name old time/op new time/op delta
Template 178ms ± 4% 173ms ± 3% -2.90% (p=0.000 n=94+96)
Unicode 85.0ms ± 4% 83.9ms ± 4% -1.23% (p=0.000 n=96+96)
GoTypes 543ms ± 3% 528ms ± 3% -2.73% (p=0.000 n=98+96)
Flate 116ms ± 3% 113ms ± 4% -2.34% (p=0.000 n=96+99)
GoParser 144ms ± 3% 140ms ± 4% -2.80% (p=0.000 n=99+97)
Reflect 344ms ± 3% 334ms ± 4% -3.02% (p=0.000 n=100+99)
Tar 106ms ± 5% 103ms ± 4% -3.30% (p=0.000 n=98+94)
XML 198ms ± 5% 192ms ± 4% -2.88% (p=0.000 n=92+95)
[Geo mean] 178ms 173ms -2.65%
name old user-time/op new user-time/op delta
Template 229ms ± 5% 224ms ± 5% -2.36% (p=0.000 n=95+99)
Unicode 107ms ± 6% 106ms ± 5% -1.13% (p=0.001 n=93+95)
GoTypes 696ms ± 4% 679ms ± 4% -2.45% (p=0.000 n=97+99)
Flate 137ms ± 4% 134ms ± 5% -2.66% (p=0.000 n=99+96)
GoParser 176ms ± 5% 172ms ± 8% -2.27% (p=0.000 n=98+100)
Reflect 430ms ± 6% 411ms ± 5% -4.46% (p=0.000 n=100+92)
Tar 128ms ±13% 123ms ±13% -4.21% (p=0.000 n=100+100)
XML 239ms ± 6% 233ms ± 6% -2.50% (p=0.000 n=95+97)
[Geo mean] 220ms 213ms -2.76%
Change-Id: I15c7d6268347f8358e75066dfdbd77db24e8d0c1
Reviewed-on: https://go-review.googlesource.com/42145
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Now that we no longer generate dead code,
it is possible to follow block predecessors
into infinite loops with no variable definitions,
causing an infinite loop during phi insertion.
To fix that, check explicitly whether the predecessor
is dead in lookupVarOutgoing, and if so, bail.
The loop in lookupVarOutgoing is very hot code,
so I am wary of adding anything to it.
However, a long, CPU-only benchmarking run shows no
performance impact at all.
Fixes#19783
Change-Id: I8ef8d267e0b20a29b5cb0fecd7084f76c6f98e47
Reviewed-on: https://go-review.googlesource.com/38913
Reviewed-by: David Chase <drchase@google.com>
Simple phi insertion already had a heuristic to check
for dead blocks, namely having no predecessors.
When we stopped generating code for dead blocks,
we eliminated some values contained in more subtle
dead blocks, which confused phi insertion.
Compensate by beefing up the reachability check.
Fixes#19678
Change-Id: I0081e4a46f7ce2f69b131a34a0553874a0cb373e
Reviewed-on: https://go-review.googlesource.com/38602
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Algorithmic improvements here are hard.
Lifting a lookup out of the loop helps a little, though.
To compile the code in #17926:
name old s/op new s/op delta
Real 146 ± 3% 140 ± 4% -3.87% (p=0.002 n=10+10)
User 143 ± 3% 139 ± 4% -3.08% (p=0.005 n=10+10)
Sys 8.28 ±35% 8.08 ±28% ~ (p=0.684 n=10+10)
Updates #17926.
Change-Id: Ic255ac8b7b409c1a53791058818b7e2cf574abe3
Reviewed-on: https://go-review.googlesource.com/33305
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
XPos is a compact (8 instead of 16 bytes on a 64bit machine) source
position representation. There is a 1:1 correspondence between each
XPos and each regular Pos, translated via a global table.
In some sense this brings back the LineHist, though positions can
track line and column information; there is a O(1) translation
between the representations (no binary search), and the translation
is factored out.
The size increase with the prior change is brought down again and
the compiler speed is in line with the master repo (measured on
the same "quiet" machine as for prior change):
name old time/op new time/op delta
Template 256ms ± 1% 262ms ± 2% ~ (p=0.063 n=5+4)
Unicode 132ms ± 1% 135ms ± 2% ~ (p=0.063 n=5+4)
GoTypes 891ms ± 1% 871ms ± 1% -2.28% (p=0.016 n=5+4)
Compiler 3.84s ± 2% 3.89s ± 2% ~ (p=0.413 n=5+4)
MakeBash 47.1s ± 1% 46.2s ± 2% ~ (p=0.095 n=5+5)
name old user-ns/op new user-ns/op delta
Template 309M ± 1% 314M ± 2% ~ (p=0.111 n=5+4)
Unicode 165M ± 1% 172M ± 9% ~ (p=0.151 n=5+5)
GoTypes 1.14G ± 2% 1.12G ± 1% ~ (p=0.063 n=5+4)
Compiler 5.00G ± 1% 4.96G ± 1% ~ (p=0.286 n=5+4)
Change-Id: Icc570cc60ab014d8d9af6976f1f961ab8828cc47
Reviewed-on: https://go-review.googlesource.com/34506
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a mostly mechanical rename followed by manual fixes where necessary.
Change-Id: Ie5c670b133db978f15dc03e50dc2da0c80fc8842
Reviewed-on: https://go-review.googlesource.com/34137
Reviewed-by: David Lazar <lazard@golang.org>
This is a step toward chosing a different position representation.
By introducing an explicit type, it will be easier to make the
transition step-wise while ensuring everything keeps running.
This has been reviewed via https://go-review.googlesource.com/#/c/34025/.
Change-Id: Ibceddcd62d8f346321ac3250e3940e9c436ed684
Reviewed-on: https://go-review.googlesource.com/34132
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Lazar <lazard@golang.org>
The algorithm for placing a phi nodes in small functions now
unreachable. This patch fix that.
Change-Id: I253d745b414fa12ee0719459c28e78a69c6861ae
Reviewed-on: https://go-review.googlesource.com/30106
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Should be more asymptotically happy.
We process each variable in turn to find all the
locations where it needs a phi (the dominance frontier
of all of its definitions). Then we add all those phis.
This takes O(n * #variables), although hopefully much less.
Then we do a single tree walk to match all the
FwdRefs with the nearest definition or phi.
This takes O(n) time.
The one remaining inefficiency is that we might end up
introducing a bunch of dead phis in the first step.
A TODO is to introduce phis only where they might be
used by a read.
The old algorithm is still faster on small functions,
so there's a cutover size (currently 500 blocks).
This algorithm supercedes the David's sparse phi
placement algorithm for large functions.
Lowers compile time of example from #14934 from
~10 sec to ~4 sec.
Lowers compile time of example from #16361 from
~4.5 sec to ~3 sec.
Lowers #16407 from ~20 min to ~30 sec.
Update #14934
Update #16361Fixes#16407
Change-Id: I1cff6364e1623c143190b6a924d7599e309db58f
Reviewed-on: https://go-review.googlesource.com/30163
Reviewed-by: David Chase <drchase@google.com>
