// Copyright 2017 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package ssa import ( "cmd/internal/obj" "sort" ) // A Cache holds reusable compiler state. // It is intended to be re-used for multiple Func compilations. type Cache struct { // Storage for low-numbered values and blocks. values [2000]Value blocks [200]Block locs [2000]Location // Reusable stackAllocState. // See stackalloc.go's {new,put}StackAllocState. stackAllocState *stackAllocState scrPoset []*poset // scratch poset to be reused // Reusable regalloc state. regallocValues []valState ValueToProgAfter []*obj.Prog debugState debugState Liveness interface{} // *gc.livenessFuncCache // Free "headers" for use by the allocators in allocators.go. // Used to put slices in sync.Pools without allocation. hdrValueSlice []*[]*Value hdrInt64Slice []*[]int64 } func (c *Cache) Reset() { nv := sort.Search(len(c.values), func(i int) bool { return c.values[i].ID == 0 }) xv := c.values[:nv] for i := range xv { xv[i] = Value{} } nb := sort.Search(len(c.blocks), func(i int) bool { return c.blocks[i].ID == 0 }) xb := c.blocks[:nb] for i := range xb { xb[i] = Block{} } nl := sort.Search(len(c.locs), func(i int) bool { return c.locs[i] == nil }) xl := c.locs[:nl] for i := range xl { xl[i] = nil } // regalloc sets the length of c.regallocValues to whatever it may use, // so clear according to length. for i := range c.regallocValues { c.regallocValues[i] = valState{} } }