go/src/cmd/compile/internal/walk/range.go

func cheapComputableIndex(width int64) bool { … }

// walkRange transforms various forms of ORANGE into
// simpler forms.  The result must be assigned back to n.
// Node n may also be modified in place, and may also be
// the returned node.
func walkRange(nrange *ir.RangeStmt) ir.Node { … }

// rangeAssign returns "n.Key = key".
func rangeAssign(n *ir.RangeStmt, key ir.Node) ir.Node { … }

// rangeAssign2 returns "n.Key, n.Value = key, value".
func rangeAssign2(n *ir.RangeStmt, key, value ir.Node) ir.Node { … }

// 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 { … }

// isMapClear checks if n is of the form:
//
//	for k := range m {
//		delete(m, k)
//	}
//
// where == for keys of map m is reflexive.
func isMapClear(n *ir.RangeStmt) bool { … }

// mapRangeClear constructs a call to runtime.mapclear for the map range idiom.
func mapRangeClear(nrange *ir.RangeStmt) ir.Node { … }

// mapClear constructs a call to runtime.mapclear for the map m.
func mapClear(m, rtyp ir.Node) ir.Node { … }

// Lower n into runtime·memclr if possible, for
// fast zeroing of slices and arrays (issue 5373).
// Look for instances of
//
//	for i := range a {
//		a[i] = zero
//	}
//
// in which the evaluation of a is side-effect-free.
//
// Parameters are as in walkRange: "for v1, v2 = range a".
func arrayRangeClear(loop *ir.RangeStmt, v1, v2, a ir.Node) ir.Node { … }

// arrayClear constructs a call to runtime.memclr for fast zeroing of slices and arrays.
func arrayClear(wbPos src.XPos, a ir.Node, nrange *ir.RangeStmt) ir.Node { … }