cleanups, switch GlobalDCE to SmallPtrSet instead of std::set

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85730 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2009-11-01 19:03:42 +00:00
parent 0037bfabd4
commit ec4c7b9766
2 changed files with 10 additions and 16 deletions

View File

@ -20,8 +20,8 @@
#include "llvm/Constants.h"
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include <set>
using namespace llvm;
STATISTIC(NumAliases , "Number of global aliases removed");
@ -39,7 +39,7 @@ namespace {
bool runOnModule(Module &M);
private:
std::set<GlobalValue*> AliveGlobals;
SmallPtrSet<GlobalValue*, 32> AliveGlobals;
/// GlobalIsNeeded - mark the specific global value as needed, and
/// recursively mark anything that it uses as also needed.
@ -91,7 +91,8 @@ bool GlobalDCE::runOnModule(Module &M) {
// The first pass is to drop initializers of global variables which are dead.
std::vector<GlobalVariable*> DeadGlobalVars; // Keep track of dead globals
for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I)
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
if (!AliveGlobals.count(I)) {
DeadGlobalVars.push_back(I); // Keep track of dead globals
I->setInitializer(0);
@ -154,14 +155,10 @@ bool GlobalDCE::runOnModule(Module &M) {
/// GlobalIsNeeded - the specific global value as needed, and
/// recursively mark anything that it uses as also needed.
void GlobalDCE::GlobalIsNeeded(GlobalValue *G) {
std::set<GlobalValue*>::iterator I = AliveGlobals.find(G);
// If the global is already in the set, no need to reprocess it.
if (I != AliveGlobals.end()) return;
// Otherwise insert it now, so we do not infinitely recurse
AliveGlobals.insert(I, G);
if (!AliveGlobals.insert(G))
return;
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(G)) {
// If this is a global variable, we must make sure to add any global values
// referenced by the initializer to the alive set.
@ -176,11 +173,9 @@ void GlobalDCE::GlobalIsNeeded(GlobalValue *G) {
// operands. Any operands of these types must be processed to ensure that
// any globals used will be marked as needed.
Function *F = cast<Function>(G);
// For all basic blocks...
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
// For all instructions...
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
// For all operands...
for (User::op_iterator U = I->op_begin(), E = I->op_end(); U != E; ++U)
if (GlobalValue *GV = dyn_cast<GlobalValue>(*U))
GlobalIsNeeded(GV);

View File

@ -1876,9 +1876,8 @@ bool GlobalOpt::OptimizeFunctions(Module &M) {
if (!F->hasName() && !F->isDeclaration())
F->setLinkage(GlobalValue::InternalLinkage);
F->removeDeadConstantUsers();
if (F->use_empty() && (F->hasLocalLinkage() ||
F->hasLinkOnceLinkage())) {
M.getFunctionList().erase(F);
if (F->use_empty() && (F->hasLocalLinkage() || F->hasLinkOnceLinkage())) {
F->eraseFromParent();
Changed = true;
++NumFnDeleted;
} else if (F->hasLocalLinkage()) {