It's not necessary to do rounding for alloca operations when the requested

alignment is equal to the stack alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 306 insertions, 0 deletions

diff --git a/lib/VMCore/Value.cpp b/lib/VMCore/Value.cpp
new file mode 100644
index 0000000..790ae17
--- /dev/null
+++ b/lib/VMCore/Value.cpp
@@ -0,0 +1,306 @@
+//===-- Value.cpp - Implement the Value class -----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Value and User classes.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Constant.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/InstrTypes.h"
+#include "llvm/Module.h"
+#include "llvm/ValueSymbolTable.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/LeakDetector.h"
+#include <algorithm>
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+//                                Value Class
+//===----------------------------------------------------------------------===//
+
+static inline const Type *checkType(const Type *Ty) {
+  assert(Ty && "Value defined with a null type: Error!");
+  return Ty;
+}
+
+Value::Value(const Type *ty, unsigned scid)
+  : SubclassID(scid), SubclassData(0), Ty(checkType(ty)),
+    UseList(0), Name(0) {
+  if (!isa<Constant>(this) && !isa<BasicBlock>(this))
+    assert((Ty->isFirstClassType() || Ty == Type::VoidTy ||
+           isa<OpaqueType>(ty)) &&
+           "Cannot create non-first-class values except for constants!");
+}
+
+Value::~Value() {
+#ifndef NDEBUG      // Only in -g mode...
+  // Check to make sure that there are no uses of this value that are still
+  // around when the value is destroyed.  If there are, then we have a dangling
+  // reference and something is wrong.  This code is here to print out what is
+  // still being referenced.  The value in question should be printed as
+  // a <badref>
+  //
+  if (use_begin() != use_end()) {
+    DOUT << "While deleting: " << *Ty << " %" << Name << "\n";
+    for (use_iterator I = use_begin(), E = use_end(); I != E; ++I)
+      DOUT << "Use still stuck around after Def is destroyed:"
+           << **I << "\n";
+  }
+#endif
+  assert(use_begin() == use_end() && "Uses remain when a value is destroyed!");
+
+  // If this value is named, destroy the name.  This should not be in a symtab
+  // at this point.
+  if (Name)
+    Name->Destroy();
+  
+  // There should be no uses of this object anymore, remove it.
+  LeakDetector::removeGarbageObject(this);
+}
+
+/// hasNUses - Return true if this Value has exactly N users.
+///
+bool Value::hasNUses(unsigned N) const {
+  use_const_iterator UI = use_begin(), E = use_end();
+
+  for (; N; --N, ++UI)
+    if (UI == E) return false;  // Too few.
+  return UI == E;
+}
+
+/// hasNUsesOrMore - Return true if this value has N users or more.  This is
+/// logically equivalent to getNumUses() >= N.
+///
+bool Value::hasNUsesOrMore(unsigned N) const {
+  use_const_iterator UI = use_begin(), E = use_end();
+
+  for (; N; --N, ++UI)
+    if (UI == E) return false;  // Too few.
+
+  return true;
+}
+
+
+/// getNumUses - This method computes the number of uses of this Value.  This
+/// is a linear time operation.  Use hasOneUse or hasNUses to check for specific
+/// values.
+unsigned Value::getNumUses() const {
+  return (unsigned)std::distance(use_begin(), use_end());
+}
+
+static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
+  ST = 0;
+  if (Instruction *I = dyn_cast<Instruction>(V)) {
+    if (BasicBlock *P = I->getParent())
+      if (Function *PP = P->getParent())
+        ST = &PP->getValueSymbolTable();
+  } else if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
+    if (Function *P = BB->getParent()) 
+      ST = &P->getValueSymbolTable();
+  } else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
+    if (Module *P = GV->getParent()) 
+      ST = &P->getValueSymbolTable();
+  } else if (Argument *A = dyn_cast<Argument>(V)) {
+    if (Function *P = A->getParent()) 
+      ST = &P->getValueSymbolTable();
+  } else {
+    assert(isa<Constant>(V) && "Unknown value type!");
+    return true;  // no name is setable for this.
+  }
+  return false;
+}
+
+std::string Value::getNameStr() const {
+  if (Name == 0) return "";
+  return std::string(Name->getKeyData(),
+                     Name->getKeyData()+Name->getKeyLength());
+}
+
+void Value::setName(const std::string &name) {
+  setName(&name[0], name.size());
+}
+
+void Value::setName(const char *Name) {
+  setName(Name, Name ? strlen(Name) : 0);
+}
+
+void Value::setName(const char *NameStr, unsigned NameLen) {
+  if (NameLen == 0 && !hasName()) return;
+  assert(getType() != Type::VoidTy && "Cannot assign a name to void values!");
+  
+  // Get the symbol table to update for this object.
+  ValueSymbolTable *ST;
+  if (getSymTab(this, ST))
+    return;  // Cannot set a name on this value (e.g. constant).
+
+  if (!ST) { // No symbol table to update?  Just do the change.
+    if (NameLen == 0) {
+      // Free the name for this value.
+      Name->Destroy();
+      Name = 0;
+      return;
+    }
+    
+    if (Name) {
+      // Name isn't changing?
+      if (NameLen == Name->getKeyLength() &&
+          !memcmp(Name->getKeyData(), NameStr, NameLen))
+        return;
+      Name->Destroy();
+    }
+    
+    // NOTE: Could optimize for the case the name is shrinking to not deallocate
+    // then reallocated.
+      
+    // Create the new name.
+    Name = ValueName::Create(NameStr, NameStr+NameLen);
+    Name->setValue(this);
+    return;
+  }
+  
+  // NOTE: Could optimize for the case the name is shrinking to not deallocate
+  // then reallocated.
+  if (hasName()) {
+    // Name isn't changing?
+    if (NameLen == Name->getKeyLength() &&
+        !memcmp(Name->getKeyData(), NameStr, NameLen))
+      return;
+
+    // Remove old name.
+    ST->removeValueName(Name);
+    Name->Destroy();
+    Name = 0;
+
+    if (NameLen == 0)
+      return;
+  }
+
+  // Name is changing to something new.
+  Name = ST->createValueName(NameStr, NameLen, this);
+}
+
+
+/// takeName - transfer the name from V to this value, setting V's name to
+/// empty.  It is an error to call V->takeName(V). 
+void Value::takeName(Value *V) {
+  ValueSymbolTable *ST = 0;
+  // If this value has a name, drop it.
+  if (hasName()) {
+    // Get the symtab this is in.
+    if (getSymTab(this, ST)) {
+      // We can't set a name on this value, but we need to clear V's name if
+      // it has one.
+      if (V->hasName()) V->setName(0, 0);
+      return;  // Cannot set a name on this value (e.g. constant).
+    }
+    
+    // Remove old name.
+    if (ST)
+      ST->removeValueName(Name);
+    Name->Destroy();
+    Name = 0;
+  } 
+  
+  // Now we know that this has no name.
+  
+  // If V has no name either, we're done.
+  if (!V->hasName()) return;
+   
+  // Get this's symtab if we didn't before.
+  if (!ST) {
+    if (getSymTab(this, ST)) {
+      // Clear V's name.
+      V->setName(0, 0);
+      return;  // Cannot set a name on this value (e.g. constant).
+    }
+  }
+  
+  // Get V's ST, this should always succed, because V has a name.
+  ValueSymbolTable *VST;
+  bool Failure = getSymTab(V, VST);
+  assert(!Failure && "V has a name, so it should have a ST!");
+  
+  // If these values are both in the same symtab, we can do this very fast.
+  // This works even if both values have no symtab yet.
+  if (ST == VST) {
+    // Take the name!
+    Name = V->Name;
+    V->Name = 0;
+    Name->setValue(this);
+    return;
+  }
+  
+  // Otherwise, things are slightly more complex.  Remove V's name from VST and
+  // then reinsert it into ST.
+  
+  if (VST)
+    VST->removeValueName(V->Name);
+  Name = V->Name;
+  V->Name = 0;
+  Name->setValue(this);
+  
+  if (ST)
+    ST->reinsertValue(this);
+}
+
+
+// uncheckedReplaceAllUsesWith - This is exactly the same as replaceAllUsesWith,
+// except that it doesn't have all of the asserts.  The asserts fail because we
+// are half-way done resolving types, which causes some types to exist as two
+// different Type*'s at the same time.  This is a sledgehammer to work around
+// this problem.
+//
+void Value::uncheckedReplaceAllUsesWith(Value *New) {
+  while (!use_empty()) {
+    Use &U = *UseList;
+    // Must handle Constants specially, we cannot call replaceUsesOfWith on a
+    // constant!
+    if (Constant *C = dyn_cast<Constant>(U.getUser())) {
+      if (!isa<GlobalValue>(C))
+        C->replaceUsesOfWithOnConstant(this, New, &U);
+      else
+        U.set(New);
+    } else {
+      U.set(New);
+    }
+  }
+}
+
+void Value::replaceAllUsesWith(Value *New) {
+  assert(New && "Value::replaceAllUsesWith(<null>) is invalid!");
+  assert(New != this && "this->replaceAllUsesWith(this) is NOT valid!");
+  assert(New->getType() == getType() &&
+         "replaceAllUses of value with new value of different type!");
+
+  uncheckedReplaceAllUsesWith(New);
+}
+
+//===----------------------------------------------------------------------===//
+//                                 User Class
+//===----------------------------------------------------------------------===//
+
+// replaceUsesOfWith - Replaces all references to the "From" definition with
+// references to the "To" definition.
+//
+void User::replaceUsesOfWith(Value *From, Value *To) {
+  if (From == To) return;   // Duh what?
+
+  assert(!isa<Constant>(this) || isa<GlobalValue>(this) &&
+         "Cannot call User::replaceUsesofWith on a constant!");
+
+  for (unsigned i = 0, E = getNumOperands(); i != E; ++i)
+    if (getOperand(i) == From) {  // Is This operand is pointing to oldval?
+      // The side effects of this setOperand call include linking to
+      // "To", adding "this" to the uses list of To, and
+      // most importantly, removing "this" from the use list of "From".
+      setOperand(i, To); // Fix it now...
+    }
+}
+