lib/IR/SymbolTableListTraitsImpl.h

   1 //===-- llvm/SymbolTableListTraitsImpl.h - Implementation ------*- C++ -*--===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements the stickier parts of the SymbolTableListTraits class,
  10 // and is explicitly instantiated where needed to avoid defining all this code
  11 // in a widely used header.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_LIB_IR_SYMBOLTABLELISTTRAITSIMPL_H
  16 #define LLVM_LIB_IR_SYMBOLTABLELISTTRAITSIMPL_H
  17
  18 #include "llvm/IR/SymbolTableListTraits.h"
  19 #include "llvm/IR/ValueSymbolTable.h"
  20
  21 namespace llvm {
  22
  23 /// setSymTabObject - This is called when (f.e.) the parent of a basic block
  24 /// changes.  This requires us to remove all the instruction symtab entries from
  25 /// the current function and reinsert them into the new function.
  26 template <typename ValueSubClass>
  27 template <typename TPtr>
  28 void SymbolTableListTraits<ValueSubClass>::setSymTabObject(TPtr *Dest,
  29                                                            TPtr Src) {
  30   // Get the old symtab and value list before doing the assignment.
  31   ValueSymbolTable *OldST = getSymTab(getListOwner());
  32
  33   // Do it.
  34   *Dest = Src;
  35
  36   // Get the new SymTab object.
  37   ValueSymbolTable *NewST = getSymTab(getListOwner());
  38
  39   // If there is nothing to do, quick exit.
  40   if (OldST == NewST) return;
  41
  42   // Move all the elements from the old symtab to the new one.
  43   ListTy &ItemList = getList(getListOwner());
  44   if (ItemList.empty()) return;
  45
  46   if (OldST) {
  47     // Remove all entries from the previous symtab.
  48     for (auto I = ItemList.begin(); I != ItemList.end(); ++I)
  49       if (I->hasName())
  50         OldST->removeValueName(I->getValueName());
  51   }
  52
  53   if (NewST) {
  54     // Add all of the items to the new symtab.
  55     for (auto I = ItemList.begin(); I != ItemList.end(); ++I)
  56       if (I->hasName())
  57         NewST->reinsertValue(&*I);
  58   }
  59
  60 }
  61
  62 template <typename ValueSubClass>
  63 void SymbolTableListTraits<ValueSubClass>::addNodeToList(ValueSubClass *V) {
  64   assert(!V->getParent() && "Value already in a container!!");
  65   ItemParentClass *Owner = getListOwner();
  66   V->setParent(Owner);
  67   if (V->hasName())
  68     if (ValueSymbolTable *ST = getSymTab(Owner))
  69       ST->reinsertValue(V);
  70 }
  71
  72 template <typename ValueSubClass>
  73 void SymbolTableListTraits<ValueSubClass>::removeNodeFromList(
  74     ValueSubClass *V) {
  75   V->setParent(nullptr);
  76   if (V->hasName())
  77     if (ValueSymbolTable *ST = getSymTab(getListOwner()))
  78       ST->removeValueName(V->getValueName());
  79 }
  80
  81 template <typename ValueSubClass>
  82 void SymbolTableListTraits<ValueSubClass>::transferNodesFromList(
  83     SymbolTableListTraits &L2, iterator first, iterator last) {
  84   // We only have to do work here if transferring instructions between BBs
  85   ItemParentClass *NewIP = getListOwner(), *OldIP = L2.getListOwner();
  86   if (NewIP == OldIP)
  87     return;
  88
  89   // We only have to update symbol table entries if we are transferring the
  90   // instructions to a different symtab object...
  91   ValueSymbolTable *NewST = getSymTab(NewIP);
  92   ValueSymbolTable *OldST = getSymTab(OldIP);
  93   if (NewST != OldST) {
  94     for (; first != last; ++first) {
  95       ValueSubClass &V = *first;
  96       bool HasName = V.hasName();
  97       if (OldST && HasName)
  98         OldST->removeValueName(V.getValueName());
  99       V.setParent(NewIP);
 100       if (NewST && HasName)
 101         NewST->reinsertValue(&V);
 102     }
 103   } else {
 104     // Just transferring between blocks in the same function, simply update the
 105     // parent fields in the instructions...
 106     for (; first != last; ++first)
 107       first->setParent(NewIP);
 108   }
 109 }
 110
 111 } // End llvm namespace
 112
 113 #endif