| // 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 |
| hdrLimitSlice []*[]limit |
| } |
| |
| 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{} |
| } |
| } |