cmd/compile: move a lot of declarations outside of go.go

go.go is currently a grab bag of various unrelated type and variable
declarations. Move a bunch of them into other more relevant source
files.

There are still more that can be moved, but these were the low hanging
fruit with obvious homes.

No code/comment changes. Just shuffling stuff around.

Change-Id: I43dbe1a5b8b707709c1a3a034c693d38b8465063
Reviewed-on: https://go-review.googlesource.com/21561
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/compile/internal/gc/const.go

@@ -10,6 +10,59 @@ import (
 	"strings"
 )
 
+// Ctype describes the constant kind of an "ideal" (untyped) constant.
+type Ctype int8
+
+const (
+	CTxxx Ctype = iota
+
+	CTINT
+	CTRUNE
+	CTFLT
+	CTCPLX
+	CTSTR
+	CTBOOL
+	CTNIL
+)
+
+type Val struct {
+	// U contains one of:
+	// bool     bool when n.ValCtype() == CTBOOL
+	// *Mpint   int when n.ValCtype() == CTINT, rune when n.ValCtype() == CTRUNE
+	// *Mpflt   float when n.ValCtype() == CTFLT
+	// *Mpcplx  pair of floats when n.ValCtype() == CTCPLX
+	// string   string when n.ValCtype() == CTSTR
+	// *Nilval  when n.ValCtype() == CTNIL
+	U interface{}
+}
+
+func (v Val) Ctype() Ctype {
+	switch x := v.U.(type) {
+	default:
+		Fatalf("unexpected Ctype for %T", v.U)
+		panic("not reached")
+	case nil:
+		return 0
+	case *NilVal:
+		return CTNIL
+	case bool:
+		return CTBOOL
+	case *Mpint:
+		if x.Rune {
+			return CTRUNE
+		}
+		return CTINT
+	case *Mpflt:
+		return CTFLT
+	case *Mpcplx:
+		return CTCPLX
+	case string:
+		return CTSTR
+	}
+}
+
+type NilVal struct{}
+
 // IntLiteral returns the Node's literal value as an integer.
 func (n *Node) IntLiteral() (x int64, ok bool) {
 	switch {

src/cmd/compile/internal/gc/dcl.go

@@ -26,6 +26,12 @@ func dflag() bool {
 	return true
 }
 
+var externdcl []*Node
+
+var blockgen int32 // max block number
+
+var block int32 // current block number
+
 // dclstack maintains a stack of shadowed symbol declarations so that
 // popdcl can restore their declarations when a block scope ends.
 // The stack is maintained as a linked list, using Sym's Link field.

src/cmd/compile/internal/gc/go.go

@@ -5,7 +5,6 @@
 package gc
 
 import (
-	"bytes"
 	"cmd/compile/internal/ssa"
 	"cmd/internal/obj"
 )
@@ -16,44 +15,6 @@ const (
 	MaxStackVarSize = 10 * 1024 * 1024
 )
 
-type Val struct {
-	// U contains one of:
-	// bool     bool when n.ValCtype() == CTBOOL
-	// *Mpint   int when n.ValCtype() == CTINT, rune when n.ValCtype() == CTRUNE
-	// *Mpflt   float when n.ValCtype() == CTFLT
-	// *Mpcplx  pair of floats when n.ValCtype() == CTCPLX
-	// string   string when n.ValCtype() == CTSTR
-	// *Nilval  when n.ValCtype() == CTNIL
-	U interface{}
-}
-
-type NilVal struct{}
-
-func (v Val) Ctype() Ctype {
-	switch x := v.U.(type) {
-	default:
-		Fatalf("unexpected Ctype for %T", v.U)
-		panic("not reached")
-	case nil:
-		return 0
-	case *NilVal:
-		return CTNIL
-	case bool:
-		return CTBOOL
-	case *Mpint:
-		if x.Rune {
-			return CTRUNE
-		}
-		return CTINT
-	case *Mpflt:
-		return CTFLT
-	case *Mpcplx:
-		return CTCPLX
-	case string:
-		return CTSTR
-	}
-}
-
 type Pkg struct {
 	Name     string // package name, e.g. "sys"
 	Path     string // string literal used in import statement, e.g. "runtime/internal/sys"
@@ -119,35 +80,6 @@ const (
 	SymAlgGen
 )
 
-// Ctype describes the constant kind of an "ideal" (untyped) constant.
-type Ctype int8
-
-const (
-	CTxxx Ctype = iota
-
-	CTINT
-	CTRUNE
-	CTFLT
-	CTCPLX
-	CTSTR
-	CTBOOL
-	CTNIL
-)
-
-// ChanDir is whether a channel can send, receive, or both.
-type ChanDir uint8
-
-func (c ChanDir) CanRecv() bool { return c&Crecv != 0 }
-func (c ChanDir) CanSend() bool { return c&Csend != 0 }
-
-const (
-	// types of channel
-	// must match ../../../../reflect/type.go:/ChanDir
-	Crecv ChanDir = 1 << 0
-	Csend ChanDir = 1 << 1
-	Cboth ChanDir = Crecv | Csend
-)
-
 // The Class of a variable/function describes the "storage class"
 // of a variable or function. During parsing, storage classes are
 // called declaration contexts.
@@ -167,30 +99,6 @@ const (
 	PHEAP = 1 << 7 // an extra bit to identify an escaped variable
 )
 
-const (
-	Etop      = 1 << 1 // evaluated at statement level
-	Erv       = 1 << 2 // evaluated in value context
-	Etype     = 1 << 3
-	Ecall     = 1 << 4  // call-only expressions are ok
-	Efnstruct = 1 << 5  // multivalue function returns are ok
-	Eiota     = 1 << 6  // iota is ok
-	Easgn     = 1 << 7  // assigning to expression
-	Eindir    = 1 << 8  // indirecting through expression
-	Eaddr     = 1 << 9  // taking address of expression
-	Eproc     = 1 << 10 // inside a go statement
-	Ecomplit  = 1 << 11 // type in composite literal
-)
-
-type Sig struct {
-	name   string
-	pkg    *Pkg
-	isym   *Sym
-	tsym   *Sym
-	type_  *Type
-	mtype  *Type
-	offset int32
-}
-
 // note this is the runtime representation
 // of the compilers arrays.
 //
@@ -218,13 +126,6 @@ var sizeof_Array int // runtime sizeof(Array)
 // } String;
 var sizeof_String int // runtime sizeof(String)
 
-// lexlineno is the line number _after_ the most recently read rune.
-// In particular, it's advanced (or rewound) as newlines are read (or unread).
-var lexlineno int32
-
-// lineno is the line number at the start of the most recently lexed token.
-var lineno int32
-
 var pragcgobuf string
 
 var infile string
@@ -245,10 +146,6 @@ var safemode int
 
 var nolocalimports int
 
-var lexbuf bytes.Buffer
-var strbuf bytes.Buffer
-var litbuf string // LLITERAL value for use in syntax error messages
-
 var Debug [256]int
 
 var debugstr string
@@ -324,8 +221,6 @@ var maxfltval [NTYPE]*Mpflt
 
 var xtop []*Node
 
-var externdcl []*Node
-
 var exportlist []*Node
 
 var importlist []*Node // imported functions and methods with inlinable bodies
@@ -350,10 +245,6 @@ var Stksize int64 // stack size for current frame
 
 var stkptrsize int64 // prefix of stack containing pointers
 
-var blockgen int32 // max block number
-
-var block int32 // current block number
-
 var hasdefer bool // flag that curfn has defer statement
 
 var Curfn *Node
@@ -410,34 +301,6 @@ var nodfp *Node
 
 var Disable_checknil int
 
-type Flow struct {
-	Prog   *obj.Prog // actual instruction
-	P1     *Flow     // predecessors of this instruction: p1,
-	P2     *Flow     // and then p2 linked though p2link.
-	P2link *Flow
-	S1     *Flow // successors of this instruction (at most two: s1 and s2).
-	S2     *Flow
-	Link   *Flow // next instruction in function code
-
-	Active int32 // usable by client
-
-	Id     int32  // sequence number in flow graph
-	Rpo    int32  // reverse post ordering
-	Loop   uint16 // x5 for every loop
-	Refset bool   // diagnostic generated
-
-	Data interface{} // for use by client
-}
-
-type Graph struct {
-	Start *Flow
-	Num   int
-
-	// After calling flowrpo, rpo lists the flow nodes in reverse postorder,
-	// and each non-dead Flow node f has g->rpo[f->rpo] == f.
-	Rpo []*Flow
-}
-
 // interface to back end
 
 const (

src/cmd/compile/internal/gc/lex.go

@@ -6,6 +6,7 @@ package gc
 
 import (
 	"bufio"
+	"bytes"
 	"cmd/internal/obj"
 	"fmt"
 	"io"
@@ -20,6 +21,17 @@ const (
 	BOM = 0xFEFF
 )
 
+// lexlineno is the line number _after_ the most recently read rune.
+// In particular, it's advanced (or rewound) as newlines are read (or unread).
+var lexlineno int32
+
+// lineno is the line number at the start of the most recently lexed token.
+var lineno int32
+
+var lexbuf bytes.Buffer
+var strbuf bytes.Buffer
+var litbuf string // LLITERAL value for use in syntax error messages
+
 func isSpace(c rune) bool {
 	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
 }

src/cmd/compile/internal/gc/popt.go

@@ -235,6 +235,34 @@ func fixjmp(firstp *obj.Prog) {
 // for every f.Data field, for use by the client.
 // If newData is nil, f.Data will be nil.
 
+type Graph struct {
+	Start *Flow
+	Num   int
+
+	// After calling flowrpo, rpo lists the flow nodes in reverse postorder,
+	// and each non-dead Flow node f has g->rpo[f->rpo] == f.
+	Rpo []*Flow
+}
+
+type Flow struct {
+	Prog   *obj.Prog // actual instruction
+	P1     *Flow     // predecessors of this instruction: p1,
+	P2     *Flow     // and then p2 linked though p2link.
+	P2link *Flow
+	S1     *Flow // successors of this instruction (at most two: s1 and s2).
+	S2     *Flow
+	Link   *Flow // next instruction in function code
+
+	Active int32 // usable by client
+
+	Id     int32  // sequence number in flow graph
+	Rpo    int32  // reverse post ordering
+	Loop   uint16 // x5 for every loop
+	Refset bool   // diagnostic generated
+
+	Data interface{} // for use by client
+}
+
 var flowmark int
 
 // MaxFlowProg is the maximum size program (counted in instructions)

src/cmd/compile/internal/gc/reflect.go

@@ -22,6 +22,16 @@ type itabEntry struct {
 var signatlist []*Node
 var itabs []itabEntry
 
+type Sig struct {
+	name   string
+	pkg    *Pkg
+	isym   *Sym
+	tsym   *Sym
+	type_  *Type
+	mtype  *Type
+	offset int32
+}
+
 // byMethodNameAndPackagePath sorts method signatures by name, then package path.
 type byMethodNameAndPackagePath []*Sig
 

src/cmd/compile/internal/gc/type.go

@@ -75,6 +75,20 @@ const (
 	dddBound   = -100 // arrays declared as [...]T start life with Bound=dddBound
 )
 
+// ChanDir is whether a channel can send, receive, or both.
+type ChanDir uint8
+
+func (c ChanDir) CanRecv() bool { return c&Crecv != 0 }
+func (c ChanDir) CanSend() bool { return c&Csend != 0 }
+
+const (
+	// types of channel
+	// must match ../../../../reflect/type.go:/ChanDir
+	Crecv ChanDir = 1 << 0
+	Csend ChanDir = 1 << 1
+	Cboth ChanDir = Crecv | Csend
+)
+
 // Types stores pointers to predeclared named types.
 //
 // It also stores pointers to several special types:

src/cmd/compile/internal/gc/typecheck.go

@@ -11,6 +11,20 @@ import (
 	"strings"
 )
 
+const (
+	Etop      = 1 << 1 // evaluated at statement level
+	Erv       = 1 << 2 // evaluated in value context
+	Etype     = 1 << 3
+	Ecall     = 1 << 4  // call-only expressions are ok
+	Efnstruct = 1 << 5  // multivalue function returns are ok
+	Eiota     = 1 << 6  // iota is ok
+	Easgn     = 1 << 7  // assigning to expression
+	Eindir    = 1 << 8  // indirecting through expression
+	Eaddr     = 1 << 9  // taking address of expression
+	Eproc     = 1 << 10 // inside a go statement
+	Ecomplit  = 1 << 11 // type in composite literal
+)
+
 // type check the whole tree of an expression.
 // calculates expression types.
 // evaluates compile time constants.