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Refactor structural* files.
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mandrigin committed Nov 15, 2019
1 parent 50bb08d commit 9a40e84
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151 changes: 151 additions & 0 deletions trie/gen_struct_step.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,151 @@
// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty off
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package trie

// Experimental code for separating data and structural information
// Each function corresponds to an opcode
// DESCRIBED: docs/programmers_guide/guide.md#separation-of-keys-and-the-structure
type structInfoReceiver interface {
leaf(length int) error
leafHash(length int) error
accountLeaf(length int, fieldset uint32) error
accountLeafHash(length int, fieldset uint32) error
extension(key []byte) error
extensionHash(key []byte) error
branch(set uint16) error
branchHash(set uint16) error
hash(number int) error
}

// GenStructStep is one step of the algorithm that generates the structural information based on the sequence of keys.
// `fieldSet` parameter specifies whether the generated leaf should be a binary string (fieldSet==0), or
// an account (in that case the opcodes `ACCOUNTLEAF`/`ACCOUNTLEAFHASH` are emitted instead of `LEAF`/`LEAFHASH`).
// `hashOnly` parameter is the function that, called for a certain prefix, determines whether the trie node for that prefix needs to be
// compressed into just hash (if `true` is returned), or constructed (if `false` is returned). Usually the `hashOnly` function is
// implemented in such a way to guarantee that certain keys are always accessible in the resulting trie (see ResolveSet.HashOnly function).
// `recursive` parameter is set to true if the algorithm's step is invoked recursively, i.e. not after a freshly provided leaf.
// Recursive invocation is used to emit opcodes for non-leaf nodes.
// `prec`, `curr`, `succ` are three full keys or prefixes that are currently visible to the algorithm. By comparing these, the algorithm
// makes decisions about the local structure, i.e. the presense of the prefix groups.
// `e` parameter is the trie builder, which uses the structure information to assemble trie on the stack and compute its hash.
// `groups` parameter is the map of the stack. each element of the `groups` slice is a bitmask, one bit per element currently on the stack.
// Whenever a `BRANCH` or `BRANCHHASH` opcode is emitted, the set of digits is taken from the corresponding `groups` item, which is
// then removed from the slice. This signifies the usage of the number of the stack items by the `BRANCH` or `BRANCHHASH` opcode.
// DESCRIBED: docs/programmers_guide/guide.md#separation-of-keys-and-the-structure
func GenStructStep(
fieldSet uint32,
hashOnly func(prefix []byte) bool,
recursive bool,
prec, curr, succ []byte,
e structInfoReceiver,
groups []uint16,
) ([]uint16, error) {
if !recursive && len(prec) == 0 {
prec = nil
}
// Calculate the prefix of the smallest prefix group containing curr
precLen := prefixLen(prec, curr)
succLen := prefixLen(succ, curr)
var maxLen int
if precLen > succLen {
maxLen = precLen
} else {
maxLen = succLen
}
//fmt.Printf("prec: %x, curr: %x, succ: %x, maxLen %d, prefix: %x\n", prec, curr, succ, maxLen, prefix)
// Add the digit immediately following the max common prefix and compute length of remainder length
extraDigit := curr[maxLen]
for maxLen >= len(groups) {
groups = append(groups, 0)
}
groups[maxLen] |= (uint16(1) << extraDigit)
//fmt.Printf("groups[%d] is now %b, len(groups) %d, prefix %x\n", maxLen, groups[maxLen], len(groups), prefix)
remainderStart := maxLen
if len(succ) > 0 || prec != nil {
remainderStart++
}
remainderLen := len(curr) - remainderStart
// Emit LEAF or EXTENSION based on the remainder
if recursive {
if remainderLen > 0 {
if hashOnly(curr[:maxLen]) {
if err := e.extensionHash(curr[remainderStart : remainderStart+remainderLen]); err != nil {
return nil, err
}
} else {
if err := e.extension(curr[remainderStart : remainderStart+remainderLen]); err != nil {
return nil, err
}
}
}
} else {
if hashOnly(curr[:maxLen]) {
if fieldSet == 0 {
if err := e.leafHash(remainderLen); err != nil {
return nil, err
}
} else {
if err := e.accountLeafHash(remainderLen, fieldSet); err != nil {
return nil, err
}
}
} else {
if fieldSet == 0 {
if err := e.leaf(remainderLen); err != nil {
return nil, err
}
} else {
if err := e.accountLeaf(remainderLen, fieldSet); err != nil {
return nil, err
}
}
}
}
// Check for the optional part
if precLen <= succLen && len(succ) > 0 {
return groups, nil
}
// Close the immediately encompassing prefix group, if needed
if len(succ) > 0 || prec != nil {
if hashOnly(curr[:maxLen]) {
if err := e.branchHash(groups[maxLen]); err != nil {
return nil, err
}
} else {
if err := e.branch(groups[maxLen]); err != nil {
return nil, err
}
}
}
groups = groups[:maxLen]
// Check the end of recursion
if precLen == 0 {
return groups, nil
}
// Identify preceding key for the recursive invocation
newCurr := curr[:precLen]
var newPrec []byte
for len(groups) > 0 && groups[len(groups)-1] == 0 {
groups = groups[:len(groups)-1]
}
if len(groups) >= 1 {
newPrec = curr[:len(groups)-1]
}

// Recursion
return GenStructStep(fieldSet, hashOnly, true, newPrec, newCurr, succ, e, groups)
}
5 changes: 3 additions & 2 deletions trie/hack.go
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@ package trie

import (
"fmt"

"github.com/ledgerwatch/turbo-geth/common"
"github.com/ledgerwatch/turbo-geth/rlp"
)
Expand Down Expand Up @@ -78,12 +79,12 @@ func hashRoot(n node, title string) {
defer returnHasherToPool(h)
defer returnHasherToPool(h1)
var hash common.Hash
hLen := h.hash(n, true, hash[:])
hLen, _ := h.hash(n, true, hash[:])
if hLen < 32 {
panic("expected hashNode")
}
fmt.Printf("%s noencode: %x\n", title, hash[:])
hLen = h1.hash(n, true, hash[:])
hLen, _ = h1.hash(n, true, hash[:])
if hLen < 32 {
panic("expected hashNode")
}
Expand Down
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