Commit graph

11 commits

Author SHA1 Message Date
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
4629f6a51d [dev.regabi] cmd/compile: merge {Selector,CallPart,Method}Expr
These three expression nodes all represent the same syntax, and so
they're represented the same within types2. And also they're not
handled that meaningfully differently throughout the rest of the
compiler to merit unique representations.

Method expressions are somewhat unique today that they're very
frequently turned into plain function names. But eventually that can
be handled by a post-typecheck desugaring phase that reduces the
number of redundant AST forms.

Passes toolstash -cmp.

Change-Id: I20df91bbd0d885c1f18ec67feb61ae1558670719
Reviewed-on: https://go-review.googlesource.com/c/go/+/280636
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 02:35:04 +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
0f732f8c91 [dev.regabi] cmd/compile: minor walkExpr cleanups
This CL cleans up a few minor points in walkExpr:

1. We don't actually care about computing the type-size of all
expressions that are walked. We care about computing the type-size of
all expressions that are *returned* by walk, as these are the
expressions that will actually be seen by the back end.

2. There's no need to call typecheck.EvalConst anymore. EvalConst used
to be responsible for doing additional constant folding during walk;
but for a while a now, it has done only as much constant folding as is
required during type checking (because doing further constant folding
led to too many issues with Go spec compliance). Instead, more
aggressive constant folding is handled entirely by SSA.

3. The code for detecting string constants and generating their
symbols can be simplified somewhat.

Passes toolstash -cmp.

Change-Id: I464ef5bceb8a97689c8f55435369a3402a5ebc55
Reviewed-on: https://go-review.googlesource.com/c/go/+/280434
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 07:10:11 +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
3f04d964ab [dev.regabi] cmd/compile: split up walkexpr1, walkstmt [generated]
walkexpr1 is the second largest non-machine-generated function in the compiler.
weighing in at 1,164 lines. Since we are destroying the git blame history
anyway, now is a good time to split each different case into its own function,
making future work on this function more manageable.
Do the same to walkstmt too for consistency, even though it is a paltry 259 lines.

[git-generate]
cd src/cmd/compile/internal/walk
rf '
	mv addstr walkAddString
	mv walkCall walkCall1
	mv walkpartialcall walkCallPart
	mv walkclosure walkClosure
	mv walkrange walkRange
	mv walkselect walkSelect
	mv walkselectcases walkSelectCases
	mv walkswitch walkSwitch
	mv walkExprSwitch walkSwitchExpr
	mv walkTypeSwitch walkSwitchType
	mv walkstmt walkStmt
	mv walkstmtlist walkStmtList
	mv walkexprlist walkExprList
	mv walkexprlistsafe walkExprListSafe
	mv walkexprlistcheap walkExprListCheap
	mv walkexpr walkExpr
	mv walkexpr1 walkExpr1
	mv walkprint walkPrint
	mv walkappend walkAppend
	mv walkcompare walkCompare
	mv walkcompareInterface walkCompareInterface
	mv walkcompareString walkCompareString

	mv appendslice appendSlice
	mv cheapexpr cheapExpr
	mv copyany walkCopy
	mv copyexpr copyExpr
	mv eqfor eqFor
	mv extendslice extendSlice
	mv finishcompare finishCompare
	mv safeexpr safeExpr

	mv walkStmt:/^\tcase ir.ORECV:/+2,/^\tcase /-2 walkRecv
	add walk.go:/^func walkRecv/-0 \
		// walkRecv walks an ORECV node.
	mv walkStmt:/^\tcase ir.ODCL:/+2,/^\tcase /-2 walkDecl
	add walk.go:/^func walkDecl/-0 \
		// walkDecl walks an ODCL node.
	mv walkStmt:/^\tcase ir.OGO:/+2,/^\tcase /-2 walkGoDefer
	add walk.go:/^func walkGoDefer/-0 \
		// walkGoDefer walks an OGO or ODEFER node.
	mv walkStmt:/^\tcase ir.OFOR,/+2,/^\tcase /-2 walkFor
	add walk.go:/^func walkFor/-0 \
		// walkFor walks an OFOR or OFORUNTIL node.
	mv walkStmt:/^\tcase ir.OIF:/+2,/^\tcase /-2 walkIf
	add walk.go:/^func walkIf/-0 \
		// walkIf walks an OIF node.
	mv walkStmt:/^\tcase ir.ORETURN:/+2,/^\tcase /-2 walkReturn
	add walk.go:/^func walkReturn/-0 \
		// walkReturn walks an ORETURN node.

	mv walkExpr1:/^\tcase ir.ODOT,/+2,/^\tcase /-2 walkDot
	add walk.go:/^func walkDot/-0 \
		// walkDot walks an ODOT or ODOTPTR node.
	mv walkExpr1:/^\tcase ir.ODOTTYPE,/+2,/^\tcase /-2 walkDotType
	add walk.go:/^func walkDotType/-0 \
		// walkDotType walks an ODOTTYPE or ODOTTYPE2 node.
	mv walkExpr1:/^\tcase ir.OLEN,/+2,/^\tcase /-2 walkLenCap
	add walk.go:/^func walkLenCap/-0 \
		// walkLenCap walks an OLEN or OCAP node.
	mv walkExpr1:/^\tcase ir.OANDAND,/+2,/^\tcase /-2 walkLogical
	add walk.go:/^func walkLogical/-0 \
		// walkLogical walks an OANDAND or OOROR node.
	mv walkExpr1:/^\tcase ir.OCALLINTER,/+2,/^\tcase /-2 walkCall
	add walk.go:/^func walkCall/-0 \
		// walkCall walks an OCALLFUNC, OCALLINTER, or OCALLMETH node.
	mv walkExpr1:/^\tcase ir.OAS,/+1,/^\tcase /-2 walkAssign
	add walk.go:/^func walkAssign/-0 \
		// walkAssign walks an OAS (AssignExpr) or OASOP (AssignOpExpr) node.
	mv walkExpr1:/^\tcase ir.OAS2:/+2,/^\tcase /-3 walkAssignList
	add walk.go:/^func walkAssignList/-0 \
		// walkAssignList walks an OAS2 node.
	mv walkExpr1:/^\tcase ir.OAS2FUNC:/+2,/^\tcase /-4 walkAssignFunc
	add walk.go:/^func walkAssignFunc/-0 \
		// walkAssignFunc walks an OAS2FUNC node.
	mv walkExpr1:/^\tcase ir.OAS2RECV:/+2,/^\tcase /-3 walkAssignRecv
	add walk.go:/^func walkAssignRecv/-0 \
		// walkAssignRecv walks an OAS2RECV node.
	mv walkExpr1:/^\tcase ir.OAS2MAPR:/+2,/^\tcase /-2 walkAssignMapRead
	add walk.go:/^func walkAssignMapRead/-0 \
		// walkAssignMapRead walks an OAS2MAPR node.
	mv walkExpr1:/^\tcase ir.ODELETE:/+2,/^\tcase /-2 walkDelete
	add walk.go:/^func walkDelete/-0 \
		// walkDelete walks an ODELETE node.
	mv walkExpr1:/^\tcase ir.OAS2DOTTYPE:/+2,/^\tcase /-2 walkAssignDotType
	add walk.go:/^func walkAssignDotType/-0 \
		// walkAssignDotType walks an OAS2DOTTYPE node.
	mv walkExpr1:/^\tcase ir.OCONVIFACE:/+2,/^\tcase /-2 walkConvInterface
	add walk.go:/^func walkConvInterface/-0 \
		// walkConvInterface walks an OCONVIFACE node.
	mv walkExpr1:/^\tcase ir.OCONV,/+2,/^\tcase /-2 walkConv
	add walk.go:/^func walkConv/-0 \
		// walkConv walks an OCONV or OCONVNOP (but not OCONVIFACE) node.
	mv walkExpr1:/^\tcase ir.ODIV,/+2,/^\tcase /-2 walkDivMod
	add walk.go:/^func walkDivMod/-0 \
		// walkDivMod walks an ODIV or OMOD node.
	mv walkExpr1:/^\tcase ir.OINDEX:/+2,/^\tcase /-2 walkIndex
	add walk.go:/^func walkIndex/-0 \
		// walkIndex walks an OINDEX node.
	# move type assertion above comment
	mv walkExpr1:/^\tcase ir.OINDEXMAP:/+/n := n/-+ walkExpr1:/^\tcase ir.OINDEXMAP:/+0
	mv walkExpr1:/^\tcase ir.OINDEXMAP:/+2,/^\tcase /-2 walkIndexMap
	add walk.go:/^func walkIndexMap/-0 \
		// walkIndexMap walks an OINDEXMAP node.
	mv walkExpr1:/^\tcase ir.OSLICEHEADER:/+2,/^\tcase /-2 walkSliceHeader
	add walk.go:/^func walkSliceHeader/-0 \
		// walkSliceHeader walks an OSLICEHEADER node.
	mv walkExpr1:/^\tcase ir.OSLICE,/+2,/^\tcase /-2 walkSlice
	add walk.go:/^func walkSlice/-0 \
		// walkSlice walks an OSLICE, OSLICEARR, OSLICESTR, OSLICE3, or OSLICE3ARR node.
	mv walkExpr1:/^\tcase ir.ONEW:/+2,/^\tcase /-2 walkNew
	add walk.go:/^func walkNew/-0 \
		// walkNew walks an ONEW node.
	# move type assertion above comment
	mv walkExpr1:/^\tcase ir.OCLOSE:/+/n := n/-+ walkExpr1:/^\tcase ir.OCLOSE:/+0
	mv walkExpr1:/^\tcase ir.OCLOSE:/+2,/^\tcase /-2 walkClose
	add walk.go:/^func walkClose/-0 \
		// walkClose walks an OCLOSE node.
	# move type assertion above comment
	mv walkExpr1:/^\tcase ir.OMAKECHAN:/+/n := n/-+ walkExpr1:/^\tcase ir.OMAKECHAN:/+0
	mv walkExpr1:/^\tcase ir.OMAKECHAN:/+2,/^\tcase /-2 walkMakeChan
	add walk.go:/^func walkMakeChan/-0 \
		// walkMakeChan walks an OMAKECHAN node.
	mv walkExpr1:/^\tcase ir.OMAKEMAP:/+2,/^\tcase /-2 walkMakeMap
	add walk.go:/^func walkMakeMap/-0 \
		// walkMakeMap walks an OMAKEMAP node.
	mv walkExpr1:/^\tcase ir.OMAKESLICE:/+2,/^\tcase /-2 walkMakeSlice
	add walk.go:/^func walkMakeSlice/-0 \
		// walkMakeSlice walks an OMAKESLICE node.
	mv walkExpr1:/^\tcase ir.OMAKESLICECOPY:/+2,/^\tcase /-2 walkMakeSliceCopy
	add walk.go:/^func walkMakeSliceCopy/-0 \
		// walkMakeSliceCopy walks an OMAKESLICECOPY node.
	mv walkExpr1:/^\tcase ir.ORUNESTR:/+2,/^\tcase /-2 walkRuneToString
	add walk.go:/^func walkRuneToString/-0 \
		// walkRuneToString walks an ORUNESTR node.
	mv walkExpr1:/^\tcase ir.OBYTES2STR,/+2,/^\tcase /-2 walkBytesRunesToString
	add walk.go:/^func walkBytesRunesToString/-0 \
		// walkBytesRunesToString walks an OBYTES2STR or ORUNES2STR node.
	mv walkExpr1:/^\tcase ir.OBYTES2STRTMP:/+2,/^\tcase /-2 walkBytesToStringTemp
	add walk.go:/^func walkBytesToStringTemp/-0 \
		// walkBytesToStringTemp walks an OBYTES2STRTMP node.
	mv walkExpr1:/^\tcase ir.OSTR2BYTES:/+2,/^\tcase /-2 walkStringToBytes
	add walk.go:/^func walkStringToBytes/-0 \
		// walkStringToBytes walks an OSTR2BYTES node.
	# move type assertion above comment
	mv walkExpr1:/^\tcase ir.OSTR2BYTESTMP:/+/n := n/-+ walkExpr1:/^\tcase ir.OSTR2BYTESTMP:/+0
	mv walkExpr1:/^\tcase ir.OSTR2BYTESTMP:/+2,/^\tcase /-2 walkStringToBytesTemp
	add walk.go:/^func walkStringToBytesTemp/-0 \
		// walkStringToBytesTemp walks an OSTR2BYTESTMP node.
	mv walkExpr1:/^\tcase ir.OSTR2RUNES:/+2,/^\tcase /-2 walkStringToRunes
	add walk.go:/^func walkStringToRunes/-0 \
		// walkStringToRunes walks an OSTR2RUNES node.
	mv walkExpr1:/^\tcase ir.OARRAYLIT,/+1,/^\tcase /-2 walkCompLit
	add walk.go:/^func walkCompLit/-0 \
		// walkCompLit walks a composite literal node: \
		// OARRAYLIT, OSLICELIT, OMAPLIT, OSTRUCTLIT (all CompLitExpr), or OPTRLIT (AddrExpr).
	mv walkExpr1:/^\tcase ir.OSEND:/+2,/^\tcase /-2 walkSend
	add walk.go:/^func walkSend/-0 \
		// walkSend walks an OSEND node.

	mv walkStmt walkStmtList \
		walkDecl \
		walkFor \
		walkGoDefer \
		walkIf \
		wrapCall \
		stmt.go

	mv walkExpr walkExpr1 walkExprList walkExprListCheap walkExprListSafe \
		cheapExpr safeExpr copyExpr \
		walkAddString \
		walkCall \
		walkCall1 \
		walkDivMod \
		walkDot \
		walkDotType \
		walkIndex \
		walkIndexMap \
		walkLogical \
		walkSend \
		walkSlice \
		walkSliceHeader \
		reduceSlice \
		bounded \
		usemethod \
		usefield \
		expr.go

	mv \
		walkAssign \
		walkAssignDotType \
		walkAssignFunc \
		walkAssignList \
		walkAssignMapRead \
		walkAssignRecv \
		walkReturn \
		fncall \
		ascompatee \
		ascompatee1 \
		ascompatet \
		reorder3 \
		reorder3save \
		aliased \
		anyAddrTaken \
		refersToName \
		refersToCommonName \
		appendSlice \
		isAppendOfMake \
		extendSlice \
		assign.go

	mv \
		walkCompare \
		walkCompareInterface \
		walkCompareString \
		finishCompare \
		eqFor \
		brcom \
		brrev \
		tracecmpArg \
		canMergeLoads \
		compare.go

	mv \
		walkConv \
		walkConvInterface \
		walkBytesRunesToString \
		walkBytesToStringTemp \
		walkRuneToString \
		walkStringToBytes \
		walkStringToBytesTemp \
		walkStringToRunes \
		convFuncName \
		rtconvfn \
		byteindex \
		walkCheckPtrAlignment \
		walkCheckPtrArithmetic \
		convert.go

	mv \
		walkAppend \
		walkClose \
		walkCopy \
		walkDelete \
		walkLenCap \
		walkMakeChan \
		walkMakeMap \
		walkMakeSlice \
		walkMakeSliceCopy \
		walkNew \
		walkPrint \
		badtype \
		callnew \
		writebarrierfn \
		isRuneCount \
		builtin.go

	mv \
		walkCompLit \
		sinit.go \
		complit.go

	mv subr.go walk.go
'

Change-Id: Ie0cf3ba4adf363c120c134d57cb7ef37934eaab9
Reviewed-on: https://go-review.googlesource.com/c/go/+/279430
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-12-23 06:39:50 +00:00