diff options
Diffstat (limited to 'src/cmd/compile/internal/walk/range.go')
| -rw-r--r-- | src/cmd/compile/internal/walk/range.go | 69 |
1 files changed, 46 insertions, 23 deletions
diff --git a/src/cmd/compile/internal/walk/range.go b/src/cmd/compile/internal/walk/range.go index 6c30fa2877..b697c243c7 100644 --- a/src/cmd/compile/internal/walk/range.go +++ b/src/cmd/compile/internal/walk/range.go @@ -38,11 +38,7 @@ func cheapComputableIndex(width int64) bool { // the returned node. func walkRange(nrange *ir.RangeStmt) ir.Node { if isMapClear(nrange) { - m := nrange.X - lno := ir.SetPos(m) - n := mapClear(m) - base.Pos = lno - return n + return mapClear(nrange) } nfor := ir.NewForStmt(nrange.Pos(), nil, nil, nil, nil) @@ -107,7 +103,7 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { // for v1 := range ha { body } if v2 == nil { - body = []ir.Node{ir.NewAssignStmt(base.Pos, v1, hv1)} + body = []ir.Node{rangeAssign(nrange, hv1)} break } @@ -116,10 +112,7 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { // v1, v2 = hv1, ha[hv1] tmp := ir.NewIndexExpr(base.Pos, ha, hv1) tmp.SetBounded(true) - // Use OAS2 to correctly handle assignments - // of the form "v1, a[v1] := range". - a := ir.NewAssignListStmt(base.Pos, ir.OAS2, []ir.Node{v1, v2}, []ir.Node{hv1, tmp}) - body = []ir.Node{a} + body = []ir.Node{rangeAssign2(nrange, hv1, tmp)} break } @@ -144,9 +137,7 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { tmp.SetBounded(true) init = append(init, ir.NewAssignStmt(base.Pos, hp, typecheck.NodAddr(tmp))) - // Use OAS2 to correctly handle assignments - // of the form "v1, a[v1] := range". - a := ir.NewAssignListStmt(base.Pos, ir.OAS2, []ir.Node{v1, v2}, []ir.Node{hv1, ir.NewStarExpr(base.Pos, hp)}) + a := rangeAssign2(nrange, hv1, ir.NewStarExpr(base.Pos, hp)) body = append(body, a) // Advance pointer as part of the late increment. @@ -172,7 +163,7 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { fn := typecheck.LookupRuntime("mapiterinit") fn = typecheck.SubstArgTypes(fn, t.Key(), t.Elem(), th) - init = append(init, mkcallstmt1(fn, reflectdata.TypePtr(t), ha, typecheck.NodAddr(hit))) + init = append(init, mkcallstmt1(fn, reflectdata.RangeMapRType(base.Pos, nrange), ha, typecheck.NodAddr(hit))) nfor.Cond = ir.NewBinaryExpr(base.Pos, ir.ONE, ir.NewSelectorExpr(base.Pos, ir.ODOT, hit, keysym), typecheck.NodNil()) fn = typecheck.LookupRuntime("mapiternext") @@ -183,11 +174,10 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { if v1 == nil { body = nil } else if v2 == nil { - body = []ir.Node{ir.NewAssignStmt(base.Pos, v1, key)} + body = []ir.Node{rangeAssign(nrange, key)} } else { elem := ir.NewStarExpr(base.Pos, ir.NewSelectorExpr(base.Pos, ir.ODOT, hit, elemsym)) - a := ir.NewAssignListStmt(base.Pos, ir.OAS2, []ir.Node{v1, v2}, []ir.Node{key, elem}) - body = []ir.Node{a} + body = []ir.Node{rangeAssign2(nrange, key, elem)} } case types.TCHAN: @@ -210,7 +200,7 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { if v1 == nil { body = nil } else { - body = []ir.Node{ir.NewAssignStmt(base.Pos, v1, hv1)} + body = []ir.Node{rangeAssign(nrange, hv1)} } // Zero hv1. This prevents hv1 from being the sole, inaccessible // reference to an otherwise GC-able value during the next channel receive. @@ -275,11 +265,10 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { if v1 != nil { if v2 != nil { // v1, v2 = hv1t, hv2 - a := ir.NewAssignListStmt(base.Pos, ir.OAS2, []ir.Node{v1, v2}, []ir.Node{hv1t, hv2}) - body = append(body, a) + body = append(body, rangeAssign2(nrange, hv1t, hv2)) } else { // v1 = hv1t - body = append(body, ir.NewAssignStmt(base.Pos, v1, hv1t)) + body = append(body, rangeAssign(nrange, hv1t)) } } } @@ -314,6 +303,36 @@ func walkRange(nrange *ir.RangeStmt) ir.Node { return n } +// rangeAssign returns "n.Key = key". +func rangeAssign(n *ir.RangeStmt, key ir.Node) ir.Node { + key = rangeConvert(n, n.Key.Type(), key, n.KeyTypeWord, n.KeySrcRType) + return ir.NewAssignStmt(n.Pos(), n.Key, key) +} + +// rangeAssign2 returns "n.Key, n.Value = key, value". +func rangeAssign2(n *ir.RangeStmt, key, value ir.Node) ir.Node { + // Use OAS2 to correctly handle assignments + // of the form "v1, a[v1] = range". + key = rangeConvert(n, n.Key.Type(), key, n.KeyTypeWord, n.KeySrcRType) + value = rangeConvert(n, n.Value.Type(), value, n.ValueTypeWord, n.ValueSrcRType) + return ir.NewAssignListStmt(n.Pos(), ir.OAS2, []ir.Node{n.Key, n.Value}, []ir.Node{key, value}) +} + +// rangeConvert returns src, converted to dst if necessary. If a +// conversion is necessary, then typeWord and srcRType are copied to +// their respective ConvExpr fields. +func rangeConvert(nrange *ir.RangeStmt, dst *types.Type, src, typeWord, srcRType ir.Node) ir.Node { + src = typecheck.Expr(src) + if dst.Kind() == types.TBLANK || types.Identical(dst, src.Type()) { + return src + } + + n := ir.NewConvExpr(nrange.Pos(), ir.OCONV, dst, src) + n.TypeWord = typeWord + n.SrcRType = srcRType + return typecheck.Expr(n) +} + // isMapClear checks if n is of the form: // // for k := range m { @@ -360,13 +379,17 @@ func isMapClear(n *ir.RangeStmt) bool { } // mapClear constructs a call to runtime.mapclear for the map m. -func mapClear(m ir.Node) ir.Node { +func mapClear(nrange *ir.RangeStmt) ir.Node { + m := nrange.X + origPos := ir.SetPos(m) + defer func() { base.Pos = origPos }() + t := m.Type() // instantiate mapclear(typ *type, hmap map[any]any) fn := typecheck.LookupRuntime("mapclear") fn = typecheck.SubstArgTypes(fn, t.Key(), t.Elem()) - n := mkcallstmt1(fn, reflectdata.TypePtr(t), m) + n := mkcallstmt1(fn, reflectdata.RangeMapRType(base.Pos, nrange), m) return walkStmt(typecheck.Stmt(n)) } |