eliminate some malloc traffic, this speeds up mem2reg by 3.4%.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33927 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2007-02-05 21:58:48 +00:00
parent 7ea07659a1
commit 40b6555561

View File

@ -23,6 +23,7 @@
#include "llvm/Instructions.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/StableBasicBlockNumbering.h"
@ -57,7 +58,7 @@ namespace {
/// Allocas - The alloca instructions being promoted.
///
std::vector<AllocaInst*> Allocas;
std::vector<AllocaInst*> &RetryList;
SmallVector<AllocaInst*, 16> &RetryList;
DominatorTree &DT;
DominanceFrontier &DF;
const TargetData &TD;
@ -90,7 +91,7 @@ namespace {
public:
PromoteMem2Reg(const std::vector<AllocaInst*> &A,
std::vector<AllocaInst*> &Retry, DominatorTree &dt,
SmallVector<AllocaInst*, 16> &Retry, DominatorTree &dt,
DominanceFrontier &df, const TargetData &td,
AliasSetTracker *ast)
: Allocas(A), RetryList(Retry), DT(dt), DF(df), TD(td), AST(ast) {}
@ -736,11 +737,12 @@ void llvm::PromoteMemToReg(const std::vector<AllocaInst*> &Allocas,
// If there is nothing to do, bail out...
if (Allocas.empty()) return;
std::vector<AllocaInst*> RetryList;
SmallVector<AllocaInst*, 16> RetryList;
PromoteMem2Reg(Allocas, RetryList, DT, DF, TD, AST).run();
// PromoteMem2Reg may not have been able to promote all of the allocas in one
// pass, run it again if needed.
std::vector<AllocaInst*> NewAllocas;
while (!RetryList.empty()) {
// If we need to retry some allocas, this is due to there being no store
// before a read in a local block. To counteract this, insert a store of
@ -752,8 +754,9 @@ void llvm::PromoteMemToReg(const std::vector<AllocaInst*> &Allocas,
RetryList[i], ++BBI);
}
std::vector<AllocaInst*> NewAllocas;
std::swap(NewAllocas, RetryList);
NewAllocas.assign(RetryList.begin(), RetryList.end());
RetryList.clear();
PromoteMem2Reg(NewAllocas, RetryList, DT, DF, TD, AST).run();
NewAllocas.clear();
}
}