cmd/compile: remove OIOTA

OIOTA used to be used to represent "iota" in the pre-typechecked IR,
before we knew whether it was safe to replace it with a constant
(because it could be redefined as a global symbol later).

However, now types2 handles constant folding, including handling of
"iota". So this can go away.

Updates #51691.

Change-Id: I3cec45b22c4c8f1c357dcc4003292c21ae32aa90
Reviewed-on: https://go-review.googlesource.com/c/go/+/393255
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>

diff --git a/src/cmd/compile/internal/ir/func.go b/src/cmd/compile/internal/ir/func.go
index 29c77444a215ef80ecc1192efb981b01fe6ed5fd..894fff23ffbe37ec41f6d0d16dd7d41bf2092b32 100644 (file)
--- a/src/cmd/compile/internal/ir/func.go
+++ b/src/cmd/compile/internal/ir/func.go
@@ -50,7 +50,6 @@ import (
 type Func struct {
        miniNode
        Body Nodes
-       Iota int64
 
        Nname    *Name        // ONAME node
        OClosure *ClosureExpr // OCLOSURE node
@@ -140,7 +139,6 @@ func NewFunc(pos src.XPos) *Func {
        f := new(Func)
        f.pos = pos
        f.op = ODCLFUNC
-       f.Iota = -1
        // Most functions are ABIInternal. The importer or symabis
        // pass may override this.
        f.ABI = obj.ABIInternal

diff --git a/src/cmd/compile/internal/ir/name.go b/src/cmd/compile/internal/ir/name.go
index f522d3e76a846ca86647f790ea1bef8e5679ecc7..ee28ca83321ea3ea1513a9cf15ff0667c0e8b023 100644 (file)
--- a/src/cmd/compile/internal/ir/name.go
+++ b/src/cmd/compile/internal/ir/name.go
@@ -166,14 +166,6 @@ func NewNameAt(pos src.XPos, sym *types.Sym) *Name {
        return newNameAt(pos, ONAME, sym)
 }
 
-// NewIota returns a new OIOTA Node.
-func NewIota(pos src.XPos, sym *types.Sym) *Name {
-       if sym == nil {
-               base.Fatalf("NewIota nil")
-       }
-       return newNameAt(pos, OIOTA, sym)
-}
-
 // NewDeclNameAt returns a new Name associated with symbol s at position pos.
 // The caller is responsible for setting Curfn.
 func NewDeclNameAt(pos src.XPos, op Op, sym *types.Sym) *Name {
@@ -223,8 +215,6 @@ func (n *Name) SetOffset(x int64) {
 }
 func (n *Name) FrameOffset() int64     { return n.Offset_ }
 func (n *Name) SetFrameOffset(x int64) { n.Offset_ = x }
-func (n *Name) Iota() int64            { return n.Offset_ }
-func (n *Name) SetIota(x int64)        { n.Offset_ = x }
 func (n *Name) Walkdef() uint8         { return n.bits.get2(miniWalkdefShift) }
 func (n *Name) SetWalkdef(x uint8) {
        if x > 3 {

diff --git a/src/cmd/compile/internal/ir/node.go b/src/cmd/compile/internal/ir/node.go
index e4cff85136c8892a56e8e17bc28bc0d2a1503052..d8c4022950547210142c550ff793a4df8ddacc9b 100644 (file)
--- a/src/cmd/compile/internal/ir/node.go
+++ b/src/cmd/compile/internal/ir/node.go
@@ -240,7 +240,6 @@ const (
        ORECV        // <-X
        ORUNESTR     // Type(X) (Type is string, X is rune)
        OSELRECV2    // like OAS2: Lhs = Rhs where len(Lhs)=2, len(Rhs)=1, Rhs[0].Op = ORECV (appears as .Var of OCASE)
-       OIOTA        // iota
        OREAL        // real(X)
        OIMAG        // imag(X)
        OCOMPLEX     // complex(X, Y)

diff --git a/src/cmd/compile/internal/ir/op_string.go b/src/cmd/compile/internal/ir/op_string.go
index f623735f6dcf2138877c4b547ed57d705578cbe7..14eb84083a8d9a459b0a98010dd581c3a3354059 100644 (file)
--- a/src/cmd/compile/internal/ir/op_string.go
+++ b/src/cmd/compile/internal/ir/op_string.go
@@ -112,62 +112,61 @@ func _() {
        _ = x[ORECV-101]
        _ = x[ORUNESTR-102]
        _ = x[OSELRECV2-103]
-       _ = x[OIOTA-104]
-       _ = x[OREAL-105]
-       _ = x[OIMAG-106]
-       _ = x[OCOMPLEX-107]
-       _ = x[OALIGNOF-108]
-       _ = x[OOFFSETOF-109]
-       _ = x[OSIZEOF-110]
-       _ = x[OUNSAFEADD-111]
-       _ = x[OUNSAFESLICE-112]
-       _ = x[OMETHEXPR-113]
-       _ = x[OMETHVALUE-114]
-       _ = x[OBLOCK-115]
-       _ = x[OBREAK-116]
-       _ = x[OCASE-117]
-       _ = x[OCONTINUE-118]
-       _ = x[ODEFER-119]
-       _ = x[OFALL-120]
-       _ = x[OFOR-121]
-       _ = x[OFORUNTIL-122]
-       _ = x[OGOTO-123]
-       _ = x[OIF-124]
-       _ = x[OLABEL-125]
-       _ = x[OGO-126]
-       _ = x[ORANGE-127]
-       _ = x[ORETURN-128]
-       _ = x[OSELECT-129]
-       _ = x[OSWITCH-130]
-       _ = x[OTYPESW-131]
-       _ = x[OFUNCINST-132]
-       _ = x[OTFUNC-133]
-       _ = x[OINLCALL-134]
-       _ = x[OEFACE-135]
-       _ = x[OITAB-136]
-       _ = x[OIDATA-137]
-       _ = x[OSPTR-138]
-       _ = x[OCFUNC-139]
-       _ = x[OCHECKNIL-140]
-       _ = x[OVARDEF-141]
-       _ = x[OVARKILL-142]
-       _ = x[OVARLIVE-143]
-       _ = x[ORESULT-144]
-       _ = x[OINLMARK-145]
-       _ = x[OLINKSYMOFFSET-146]
-       _ = x[ODYNAMICDOTTYPE-147]
-       _ = x[ODYNAMICDOTTYPE2-148]
-       _ = x[ODYNAMICTYPE-149]
-       _ = x[OTAILCALL-150]
-       _ = x[OGETG-151]
-       _ = x[OGETCALLERPC-152]
-       _ = x[OGETCALLERSP-153]
-       _ = x[OEND-154]
+       _ = x[OREAL-104]
+       _ = x[OIMAG-105]
+       _ = x[OCOMPLEX-106]
+       _ = x[OALIGNOF-107]
+       _ = x[OOFFSETOF-108]
+       _ = x[OSIZEOF-109]
+       _ = x[OUNSAFEADD-110]
+       _ = x[OUNSAFESLICE-111]
+       _ = x[OMETHEXPR-112]
+       _ = x[OMETHVALUE-113]
+       _ = x[OBLOCK-114]
+       _ = x[OBREAK-115]
+       _ = x[OCASE-116]
+       _ = x[OCONTINUE-117]
+       _ = x[ODEFER-118]
+       _ = x[OFALL-119]
+       _ = x[OFOR-120]
+       _ = x[OFORUNTIL-121]
+       _ = x[OGOTO-122]
+       _ = x[OIF-123]
+       _ = x[OLABEL-124]
+       _ = x[OGO-125]
+       _ = x[ORANGE-126]
+       _ = x[ORETURN-127]
+       _ = x[OSELECT-128]
+       _ = x[OSWITCH-129]
+       _ = x[OTYPESW-130]
+       _ = x[OFUNCINST-131]
+       _ = x[OTFUNC-132]
+       _ = x[OINLCALL-133]
+       _ = x[OEFACE-134]
+       _ = x[OITAB-135]
+       _ = x[OIDATA-136]
+       _ = x[OSPTR-137]
+       _ = x[OCFUNC-138]
+       _ = x[OCHECKNIL-139]
+       _ = x[OVARDEF-140]
+       _ = x[OVARKILL-141]
+       _ = x[OVARLIVE-142]
+       _ = x[ORESULT-143]
+       _ = x[OINLMARK-144]
+       _ = x[OLINKSYMOFFSET-145]
+       _ = x[ODYNAMICDOTTYPE-146]
+       _ = x[ODYNAMICDOTTYPE2-147]
+       _ = x[ODYNAMICTYPE-148]
+       _ = x[OTAILCALL-149]
+       _ = x[OGETG-150]
+       _ = x[OGETCALLERPC-151]
+       _ = x[OGETCALLERSP-152]
+       _ = x[OEND-153]
 }
 
-const _Op_name = "XXXNAMENONAMETYPELITERALNILADDSUBORXORADDSTRADDRANDANDAPPENDBYTES2STRBYTES2STRTMPRUNES2STRSTR2BYTESSTR2BYTESTMPSTR2RUNESSLICE2ARRPTRASAS2AS2DOTTYPEAS2FUNCAS2MAPRAS2RECVASOPCALLCALLFUNCCALLMETHCALLINTERCAPCLOSECLOSURECOMPLITMAPLITSTRUCTLITARRAYLITSLICELITPTRLITCONVCONVIFACECONVIDATACONVNOPCOPYDCLDCLFUNCDCLCONSTDCLTYPEDELETEDOTDOTPTRDOTMETHDOTINTERXDOTDOTTYPEDOTTYPE2EQNELTLEGEGTDEREFINDEXINDEXMAPKEYSTRUCTKEYLENMAKEMAKECHANMAKEMAPMAKESLICEMAKESLICECOPYMULDIVMODLSHRSHANDANDNOTNEWNOTBITNOTPLUSNEGORORPANICPRINTPRINTNPARENSENDSLICESLICEARRSLICESTRSLICE3SLICE3ARRSLICEHEADERRECOVERRECOVERFPRECVRUNESTRSELRECV2IOTAREALIMAGCOMPLEXALIGNOFOFFSETOFSIZEOFUNSAFEADDUNSAFESLICEMETHEXPRMETHVALUEBLOCKBREAKCASECONTINUEDEFERFALLFORFORUNTILGOTOIFLABELGORANGERETURNSELECTSWITCHTYPESWFUNCINSTTFUNCINLCALLEFACEITABIDATASPTRCFUNCCHECKNILVARDEFVARKILLVARLIVERESULTINLMARKLINKSYMOFFSETDYNAMICDOTTYPEDYNAMICDOTTYPE2DYNAMICTYPETAILCALLGETGGETCALLERPCGETCALLERSPEND"
+const _Op_name = "XXXNAMENONAMETYPELITERALNILADDSUBORXORADDSTRADDRANDANDAPPENDBYTES2STRBYTES2STRTMPRUNES2STRSTR2BYTESSTR2BYTESTMPSTR2RUNESSLICE2ARRPTRASAS2AS2DOTTYPEAS2FUNCAS2MAPRAS2RECVASOPCALLCALLFUNCCALLMETHCALLINTERCAPCLOSECLOSURECOMPLITMAPLITSTRUCTLITARRAYLITSLICELITPTRLITCONVCONVIFACECONVIDATACONVNOPCOPYDCLDCLFUNCDCLCONSTDCLTYPEDELETEDOTDOTPTRDOTMETHDOTINTERXDOTDOTTYPEDOTTYPE2EQNELTLEGEGTDEREFINDEXINDEXMAPKEYSTRUCTKEYLENMAKEMAKECHANMAKEMAPMAKESLICEMAKESLICECOPYMULDIVMODLSHRSHANDANDNOTNEWNOTBITNOTPLUSNEGORORPANICPRINTPRINTNPARENSENDSLICESLICEARRSLICESTRSLICE3SLICE3ARRSLICEHEADERRECOVERRECOVERFPRECVRUNESTRSELRECV2REALIMAGCOMPLEXALIGNOFOFFSETOFSIZEOFUNSAFEADDUNSAFESLICEMETHEXPRMETHVALUEBLOCKBREAKCASECONTINUEDEFERFALLFORFORUNTILGOTOIFLABELGORANGERETURNSELECTSWITCHTYPESWFUNCINSTTFUNCINLCALLEFACEITABIDATASPTRCFUNCCHECKNILVARDEFVARKILLVARLIVERESULTINLMARKLINKSYMOFFSETDYNAMICDOTTYPEDYNAMICDOTTYPE2DYNAMICTYPETAILCALLGETGGETCALLERPCGETCALLERSPEND"
 
-var _Op_index = [...]uint16{0, 3, 7, 13, 17, 24, 27, 30, 33, 35, 38, 44, 48, 54, 60, 69, 81, 90, 99, 111, 120, 132, 134, 137, 147, 154, 161, 168, 172, 176, 184, 192, 201, 204, 209, 216, 223, 229, 238, 246, 254, 260, 264, 273, 282, 289, 293, 296, 303, 311, 318, 324, 327, 333, 340, 348, 352, 359, 367, 369, 371, 373, 375, 377, 379, 384, 389, 397, 400, 409, 412, 416, 424, 431, 440, 453, 456, 459, 462, 465, 468, 471, 477, 480, 483, 489, 493, 496, 500, 505, 510, 516, 521, 525, 530, 538, 546, 552, 561, 572, 579, 588, 592, 599, 607, 611, 615, 619, 626, 633, 641, 647, 656, 667, 675, 684, 689, 694, 698, 706, 711, 715, 718, 726, 730, 732, 737, 739, 744, 750, 756, 762, 768, 776, 781, 788, 793, 797, 802, 806, 811, 819, 825, 832, 839, 845, 852, 865, 879, 894, 905, 913, 917, 928, 939, 942}
+var _Op_index = [...]uint16{0, 3, 7, 13, 17, 24, 27, 30, 33, 35, 38, 44, 48, 54, 60, 69, 81, 90, 99, 111, 120, 132, 134, 137, 147, 154, 161, 168, 172, 176, 184, 192, 201, 204, 209, 216, 223, 229, 238, 246, 254, 260, 264, 273, 282, 289, 293, 296, 303, 311, 318, 324, 327, 333, 340, 348, 352, 359, 367, 369, 371, 373, 375, 377, 379, 384, 389, 397, 400, 409, 412, 416, 424, 431, 440, 453, 456, 459, 462, 465, 468, 471, 477, 480, 483, 489, 493, 496, 500, 505, 510, 516, 521, 525, 530, 538, 546, 552, 561, 572, 579, 588, 592, 599, 607, 611, 615, 622, 629, 637, 643, 652, 663, 671, 680, 685, 690, 694, 702, 707, 711, 714, 722, 726, 728, 733, 735, 740, 746, 752, 758, 764, 772, 777, 784, 789, 793, 798, 802, 807, 815, 821, 828, 835, 841, 848, 861, 875, 890, 901, 909, 913, 924, 935, 938}
 
 func (i Op) String() string {
        if i >= Op(len(_Op_index)-1) {

diff --git a/src/cmd/compile/internal/ir/sizeof_test.go b/src/cmd/compile/internal/ir/sizeof_test.go
index fca11ffc7cbca6e3bc5c47e5510705f7d9c43229..c1167f23f8eaa1845d155915ae07889e3330e0f3 100644 (file)
--- a/src/cmd/compile/internal/ir/sizeof_test.go
+++ b/src/cmd/compile/internal/ir/sizeof_test.go
@@ -20,7 +20,7 @@ func TestSizeof(t *testing.T) {
                _32bit uintptr     // size on 32bit platforms
                _64bit uintptr     // size on 64bit platforms
        }{
-               {Func{}, 192, 328},
+               {Func{}, 184, 320},
                {Name{}, 108, 192},
        }
 

diff --git a/src/cmd/compile/internal/typecheck/func.go b/src/cmd/compile/internal/typecheck/func.go
index c6fd273bd12e5ecd83b7ee3640e12fe8d571303d..5c1a2341b630bb688ea92ba7003b636d654cf1d1 100644 (file)
--- a/src/cmd/compile/internal/typecheck/func.go
+++ b/src/cmd/compile/internal/typecheck/func.go
@@ -241,12 +241,6 @@ func tcClosure(clo *ir.ClosureExpr, top int) ir.Node {
                base.FatalfAt(fn.Pos(), "underlying closure func already typechecked: %v", fn)
        }
 
-       // Set current associated iota value, so iota can be used inside
-       // function in ConstSpec, see issue #22344
-       if x := getIotaValue(); x >= 0 {
-               fn.Iota = x
-       }
-
        ir.NameClosure(clo, ir.CurFunc)
        Func(fn)
 

diff --git a/src/cmd/compile/internal/typecheck/typecheck.go b/src/cmd/compile/internal/typecheck/typecheck.go
index 71a784168426a4a8c8438b86843eea8b9407c3f9..6b1c820818eb1537cb8f32edf33f2e19d7474f63 100644 (file)
--- a/src/cmd/compile/internal/typecheck/typecheck.go
+++ b/src/cmd/compile/internal/typecheck/typecheck.go
@@ -153,13 +153,6 @@ func Resolve(n ir.Node) (res ir.Node) {
                return n
        }
 
-       if r.Op() == ir.OIOTA {
-               if x := getIotaValue(); x >= 0 {
-                       return ir.NewInt(x)
-               }
-               return n
-       }
-
        return r
 }
 
@@ -2152,22 +2145,6 @@ func CheckReturn(fn *ir.Func) {
        }
 }
 
-// getIotaValue returns the current value for "iota",
-// or -1 if not within a ConstSpec.
-func getIotaValue() int64 {
-       if i := len(typecheckdefstack); i > 0 {
-               if x := typecheckdefstack[i-1]; x.Op() == ir.OLITERAL {
-                       return x.Iota()
-               }
-       }
-
-       if ir.CurFunc != nil && ir.CurFunc.Iota >= 0 {
-               return ir.CurFunc.Iota
-       }
-
-       return -1
-}
-
 // curpkg returns the current package, based on Curfn.
 func curpkg() *types.Pkg {
        fn := ir.CurFunc

diff --git a/src/cmd/compile/internal/typecheck/universe.go b/src/cmd/compile/internal/typecheck/universe.go
index 0254d96e6825e5adac1735e78df950694e0d62b7..204c31b7582f92e0ddccd0828c4770916aac3063 100644 (file)
--- a/src/cmd/compile/internal/typecheck/universe.go
+++ b/src/cmd/compile/internal/typecheck/universe.go
@@ -7,7 +7,6 @@ package typecheck
 import (
        "go/constant"
 
-       "cmd/compile/internal/base"
        "cmd/compile/internal/ir"
        "cmd/compile/internal/types"
        "cmd/internal/src"
@@ -108,9 +107,6 @@ func InitUniverse() {
        nnil.(*ir.NilExpr).SetSym(s)
        s.Def = nnil
 
-       s = types.BuiltinPkg.Lookup("iota")
-       s.Def = ir.NewIota(base.Pos, s)
-
        // initialize okfor
        for et := types.Kind(0); et < types.NTYPE; et++ {
                if types.IsInt[et] || et == types.TIDEAL {