Commit Graph

19 Commits

Author SHA1 Message Date
Matthew Dempsky 7fd84c6e46 [dev.regabi] cmd/compile: remove OCLOSUREREAD
After the previous CLs, all closure reads are handled during SSA
construction.

Change-Id: Iad67b01fa2d3798f50ea647be7ccf8195f189c27
Reviewed-on: https://go-review.googlesource.com/c/go/+/281512
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>
2021-01-10 08:02:23 +00:00
Matthew Dempsky 950cf4d46c [dev.regabi] cmd/compile: bind closure vars during SSA constructions
For function literals that aren't inlined or directly called, we need
to pass their arguments via a closure struct. This also means we need
to rewrite uses of closure variables to access from this closure
struct.

Currently we do this rewrite in a pass before walking begins. This CL
moves the code to SSA construction instead, alongside binding other
input parameters.

Change-Id: I13538ef3394e2d6f75d5b7b2d0adbb00db812dc2
Reviewed-on: https://go-review.googlesource.com/c/go/+/281352
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2021-01-10 08:02:06 +00:00
Matthew Dempsky 8b2efa990b [dev.regabi] cmd/compile: deref PAUTOHEAPs during SSA construction
Currently, during walk we rewrite PAUTOHEAP uses into derefs of their
corresponding Heapaddr, but we can easily do this instead during SSA
construction. This does involve updating two test cases:

* nilptr3.go

This file had a test that we emit a "removed nil check" diagnostic for
the implicit dereference from accessing a PAUTOHEAP variable. This CL
removes this diagnostic, since it's not really useful to end users:
from the user's point of view, there's no pointer anyway, so they
needn't care about whether we check for nil or not. That's a purely
internal detail. And with the PAUTOHEAP dereference handled during SSA
construction, we can more robustly ensure this happens, rather than
relying on setting a flag in walk and hoping that SSA sees it.

* issue20780.go

Previously, when PAUTOHEAPs were dereferenced during walk, it had a
consequence that when they're passed as a function call argument, they
would first get copied to the stack before being copied to their
actual destination. Moving the dereferencing to SSA had a side-effect
of eliminating this unnecessary temporary, and copying directly to the
destination parameter.

The test is updated to instead call "g(h(), h())" where h() returns a
large value, as the first result will always need to be spilled
somewhere will calling the second function. Maybe eventually we're
smart enough to realize it can be spilled to the heap, but we don't do
that today.

Because I'm concerned that the direct copy-to-parameter optimization
could interfere with race-detector instrumentation (e.g., maybe the
copies were previously necessary to ensure they're not clobbered by
inserted raceread calls?), I've also added issue20780b.go to exercise
this in a few different ways.

Change-Id: I720598cb32b17518bc10a03e555620c0f25fd28d
Reviewed-on: https://go-review.googlesource.com/c/go/+/281293
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2021-01-10 08:01:49 +00:00
Matthew Dempsky f24e40c14a [dev.regabi] cmd/compile: remove Name.Class_ accessors
These aren't part of the Node interface anymore, so no need to keep
them around.

Passes toolstash -cmp.

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

: Fix one off case that causes trouble for rf.
sed -i -e 's/n.SetClass(ir.PAUTO)/n.Class_ = ir.PAUTO/' ../ssa/export_test.go

pkgs=$(go list . ../...)
rf '
	ex '"$(echo $pkgs)"' {
		var n *Name
		var c Class
		n.Class() -> n.Class_
		n.SetClass(c) -> n.Class_ = c
	}

	rm Name.Class
	rm Name.SetClass
	mv Name.Class_ Name.Class
'

Change-Id: Ifb304bf4691a8c455456aabd8aa77178d4a49500
Reviewed-on: https://go-review.googlesource.com/c/go/+/281294
Trust: Matthew Dempsky <mdempsky@google.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>
2021-01-04 10:30:09 +00:00
Matthew Dempsky fd22df9905 [dev.regabi] cmd/compile: remove idempotent Name() calls [generated]
[git-generate]
cd src/cmd/compile/internal/ir
pkgs=$(grep -l -w Name ../*/*.go | xargs dirname | sort -u | grep -v '/ir$')
rf '
	ex . '"$(echo $pkgs)"' {
		var n *Name
		n.Name() -> n
	}
'

Change-Id: I6bfce6417a6dba833d2f652ae212a32c11bc5ef6
Reviewed-on: https://go-review.googlesource.com/c/go/+/280972
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>
2021-01-01 03:02:29 +00:00
Cuong Manh Le 77fd81a3e6 [dev.regabi] cmd/compile: use names for keep alive variables in function call
Back to pre Russquake, Node.Nbody of OCALL* node is used to attach
variables which must be kept alive during that call.

Now after Russquake, we have CallExpr to represent a function call,
so use a dedicated field for those variables instead.

Passes toolstash -cmp.

Change-Id: I4f40ebefcc7c41cdcc4e29c7a6d8496a083b68f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/280733
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>
2020-12-31 09:43:13 +00:00
Cuong Manh Le 82ab3d1448 [dev.regabi] cmd/compile: use *ir.Name for Decl.X
Passes toolstash -cmp.

Change-Id: I505577d067eda3512f6d78618fc0eff061a71e3c
Reviewed-on: https://go-review.googlesource.com/c/go/+/280732
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>
2020-12-30 00:48:19 +00:00
Matthew Dempsky a5ec920160 [dev.regabi] cmd/compile: more Linksym cleanup
This largely gets rid of the remaining direct Linksym calls, hopefully
enough to discourage people from following bad existing practice until
Sym.Linksym can be removed entirely.

Passes toolstash -cmp.

Change-Id: I5d8f8f703ace7256538fc79648891ede0d879dc2
Reviewed-on: https://go-review.googlesource.com/c/go/+/280641
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-29 07:55:00 +00:00
Matthew Dempsky ec59b197d5 [dev.regabi] cmd/compile: rewrite to use linksym helpers [generated]
Passes toolstash -cmp.

[git-generate]
cd src/cmd/compile/internal/gc
pkgs=$(grep -l -w Linksym ../*/*.go | xargs dirname | grep -v '/gc$' | sort -u)
rf '
	ex . '"$(echo $pkgs)"' {
		import "cmd/compile/internal/ir"
		import "cmd/compile/internal/reflectdata"
		import "cmd/compile/internal/staticdata"
		import "cmd/compile/internal/types"

		avoid reflectdata.TypeLinksym
		avoid reflectdata.TypeLinksymLookup
		avoid reflectdata.TypeLinksymPrefix
		avoid staticdata.FuncLinksym

		var f *ir.Func
		var n *ir.Name
		var s string
		var t *types.Type

		f.Sym().Linksym() -> f.Linksym()
		n.Sym().Linksym() -> n.Linksym()

		reflectdata.TypeSym(t).Linksym() -> reflectdata.TypeLinksym(t)
		reflectdata.TypeSymPrefix(s, t).Linksym() -> reflectdata.TypeLinksymPrefix(s, t)
		staticdata.FuncSym(n.Sym()).Linksym() -> staticdata.FuncLinksym(n)
		types.TypeSymLookup(s).Linksym() -> reflectdata.TypeLinksymLookup(s)
	}
'

Change-Id: I7a3ae1dcd61bcdf4a29f708ff12f7f80c2b280c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/280640
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-29 07:54:55 +00:00
Matthew Dempsky 25c613c02d [dev.regabi] cmd/compile: add Linksym helpers
Syms are meant to be just interned (pkg, name) tuples, and are a
purely abstract, Go-language concept. As such, associating them with
linker symbols (a low-level, implementation-oriented detail) is
inappropriate.

There's still work to be done before linker symbols can be directly
attached to their appropriate, higher-level objects instead. But in
the mean-time, we can at least add helper functions and discourage
folks from using Sym.Linksym directly. The next CL will mechanically
rewrite code to use these helpers where possible.

Passes toolstash -cmp.

Change-Id: I413bd1c80bce056304f9a7343526bd153f2b9c7d
Reviewed-on: https://go-review.googlesource.com/c/go/+/280639
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-29 07:54:40 +00:00
Matthew Dempsky 6acbae4fcc [dev.regabi] cmd/compile: address some ir TODOs
Previously, ODOTTYPE/ODOTTYPE2 were forced to reuse some available
Node fields for storing pointers to runtime type descriptors. This
resulted in awkward field types for TypeAssertExpr and AddrExpr.

This CL gives TypeAssertExpr proper fields for the runtime type
descriptors, and also tightens the field types as
possible/appropriate.

Passes toolstash -cmp.

Change-Id: I521ee7a1462affc5459de33a0de6c68a7d6416ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/280637
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
2020-12-29 02:49:00 +00:00
Matthew Dempsky 3383b5c74a [dev.regabi] cmd/compile: flatten dependency graph [generated]
This CL shuffles a couple functions around to help flatten the package
dependency graph somewhat:

1. ssa.LosesStmtMark is only ever used in associated with an
objw.Prog, so we might as well move it to that package. This removes a
dependency from objw (a relatively low-level utility package that
wraps cmd/internal/obj) on ssa (a large and relatively high-level
package).

2. Moves liveness.SetTypeBits into a new package typebits. A
single-function package is a bit on the silly side, but reflectdata
shouldn't need to depend on liveness (nor vice versa).

[git-generate]
cd src/cmd/compile/internal/ssa
rf '
	mv LosesStmtMark prog.go
	mv prog.go cmd/compile/internal/objw
'

cd ../liveness
rf '
	mv SetTypeBits Set
	mv Set typebits.go
	rm typebits.go:/Copyright/+4,/^package/-0
	mv typebits.go cmd/compile/internal/typebits
'

Change-Id: Ic9a983f0ad6c0cf1a537f99889699a8444699e6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/280447
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-28 08:06:26 +00:00
Matthew Dempsky 135ce1c485 [dev.regabi] cmd/compile: desugar OMETHEXPR into ONAME during walk
A subsequent CL will change FuncName to lazily create the ONAME nodes,
which isn't currently safe to do during SSA construction, because that
phase is concurrent.

Passes toolstash -cmp.

Change-Id: Ic24acc1d1160ad93b70ced3baa468f750e689ea6
Reviewed-on: https://go-review.googlesource.com/c/go/+/280435
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-28 07:43:31 +00:00
Matthew Dempsky 0de8eafd98 [dev.regabi] cmd/compile: remove SelectorExpr.Offset field
Now that the previous CL ensures we always set SelectorExpr.Selection,
we can replace the SelectorExpr.Offset field with a helper method that
simply returns SelectorExpr.Selection.Offset.

Passes toolstash -cmp.

Change-Id: Id0f22b8b1980397b668f6860d27cb197b90ff52a
Reviewed-on: https://go-review.googlesource.com/c/go/+/280433
Trust: Matthew Dempsky <mdempsky@google.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>
2020-12-28 03:39:08 +00:00
Matthew Dempsky e4f293d853 [dev.regabi] cmd/compile: fix OCALLMETH desugaring
During walkCall, there's a half-hearted attempt at rewriting OCALLMETH
expressions into regular function calls by moving the receiver
argument into n.Args with the rest of the arguments. But the way it
does this leaves the AST in an inconsistent state (an ODOTMETH node
with no X expression), and leaves a lot of duplicate work for the rest
of the backend to deal with.

By simply rewriting OCALLMETH expressions into proper OCALLFUNC
expressions, we eliminate a ton of unnecessary code duplication during
SSA construction and avoid creation of invalid method-typed variables.

Passes toolstash -cmp.

Change-Id: I4d5c5f90a79f8994059b2d0ae472182e08096c0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/280294
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-12-25 11:15:41 +00:00
Cuong Manh Le 082cc8b7d9 [dev.regabi] cmd/compile: change ir.IsAssignable -> ir.IsAddressable
ir.IsAssignable does not include map index expression, so it should be
named ir.IsAddressable instead.

[git-generate]

cd src/cmd/compile/internal/ir
rf '
  mv IsAssignable IsAddressable
'

Change-Id: Ief6188e7b784ba9592d7b0cbec33b5f70d78f638
Reviewed-on: https://go-review.googlesource.com/c/go/+/279436
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>
2020-12-24 16:56:19 +00:00
Matthew Dempsky d1d64e4cea [dev.regabi] cmd/compile: split SliceExpr.List into separate fields
Passes toolstash -cmp.

Change-Id: I4e31154d04d99f2b80bec6a2c571a2a4a3f2ec99
Reviewed-on: https://go-review.googlesource.com/c/go/+/279959
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-12-23 14:38:23 +00:00
Matthew Dempsky d19018e8f1 [dev.regabi] cmd/compile: split SliceHeaderExpr.LenCap into separate fields
Passes toolstash -cmp.

Change-Id: Ifc98a408c154a05997963e2c731466842ebbf50e
Reviewed-on: https://go-review.googlesource.com/c/go/+/279958
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>
2020-12-23 14:09:23 +00:00
Russ Cox 6c34d2f420 [dev.regabi] cmd/compile: split out package ssagen [generated]
[git-generate]

cd src/cmd/compile/internal/gc
rf '
	# maxOpenDefers is declared in ssa.go but used only by walk.
	mv maxOpenDefers walk.go

	# gc.Arch -> ssagen.Arch
	# It is not as nice but will do for now.
	mv Arch ArchInfo
	mv thearch Arch
	mv Arch ArchInfo arch.go

	# Pull dwarf out of pgen.go.
	mv debuginfo declPos createDwarfVars preInliningDcls \
		createSimpleVars createSimpleVar \
		createComplexVars createComplexVar \
		dwarf.go

	# Pull high-level compilation out of pgen.go,
	# leaving only the SSA code.
	mv compilequeue funccompile compile compilenow \
		compileFunctions isInlinableButNotInlined \
		initLSym \
		compile.go

	mv BoundsCheckFunc GCWriteBarrierReg ssa.go
	mv largeStack largeStackFrames CheckLargeStacks pgen.go

	# All that is left in dcl.go is the nowritebarrierrecCheck
	mv dcl.go nowb.go

	# Export API and unexport non-API.
	mv initssaconfig InitConfig
	mv isIntrinsicCall IsIntrinsicCall
	mv ssaDumpInline DumpInline
	mv initSSATables InitTables
	mv initSSAEnv InitEnv
	mv compileSSA Compile
	mv stackOffset StackOffset
	mv canSSAType TypeOK
	mv SSAGenState State
	mv FwdRefAux fwdRefAux

	mv cgoSymABIs CgoSymABIs
	mv readSymABIs ReadSymABIs
	mv initLSym InitLSym
	mv useABIWrapGen symabiDefs CgoSymABIs ReadSymABIs InitLSym selectLSym makeABIWrapper setupTextLSym abi.go

	mv arch.go abi.go nowb.go phi.go pgen.go pgen_test.go ssa.go cmd/compile/internal/ssagen
'
rm go.go gsubr.go

Change-Id: I47fad6cbf1d1e583fd9139003a08401d7cd048a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/279476
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-12-23 06:39:29 +00:00