D/ldc
1
0
Fork 0
mirror of https://github.com/xomboverlord/ldc.git synced 2026-01-27 01:53:13 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

Oops, I accidentally pushed r1486 before the last touches were committed.

Browse Source
This commit is contained in:
Frits van Bommel
2009-06-08 13:52:45 +02:00
parent 8044a67720
commit 9ba306a42f
1 changed files with 9 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
gen/passes/GarbageCollect2Stack.cpp
View File

@@ -50,12 +50,10 @@ namespace {
struct Analysis {
TargetData& TD;
const Module& M;
DominatorTree& DT;
CallGraph* CG;
CallGraphNode* CGNode;
const Type* getTypeFor(Value* typeinfo) const;
bool isSafeToStackAllocate(Instruction* Alloc);
};
}
@@ -319,6 +317,8 @@ static void RemoveCall(CallSite CS, const Analysis& A) {
CS.getInstruction()->eraseFromParent();
}
static bool isSafeToStackAllocate(Instruction* Alloc, DominatorTree& DT);
/// runOnFunction - Top level algorithm.
///
bool GarbageCollect2Stack::runOnFunction(Function &F) {
@@ -329,7 +329,7 @@ bool GarbageCollect2Stack::runOnFunction(Function &F) {
CallGraph* CG = getAnalysisIfAvailable<CallGraph>();
CallGraphNode* CGNode = CG ? (*CG)[&F] : NULL;
Analysis A = { TD, *M, DT, CG, CGNode };
Analysis A = { TD, *M, CG, CGNode };
BasicBlock& Entry = F.getEntryBlock();
@@ -370,7 +370,7 @@ bool GarbageCollect2Stack::runOnFunction(Function &F) {
DEBUG(DOUT << "GarbageCollect2Stack inspecting: " << *Inst);
if (!info->analyze(CS, A) || !A.isSafeToStackAllocate(Inst))
if (!info->analyze(CS, A) || !isSafeToStackAllocate(Inst, DT))
continue;
// Let's alloca this!
@@ -432,8 +432,8 @@ const Type* Analysis::getTypeFor(Value* typeinfo) const {
///
/// Based on LLVM's PointerMayBeCaptured(), which only does escape analysis but
/// doesn't care about loops.
bool Analysis::isSafeToStackAllocate(Instruction* Alloc) {
assert(isa<PointerType>(Alloc->getType()) && "Capture is for pointers only!");
bool isSafeToStackAllocate(Instruction* Alloc, DominatorTree& DT) {
assert(isa<PointerType>(Alloc->getType()) && "Allocation is not a pointer?");
Value* V = Alloc;
SmallVector<Use*, 16> Worklist;
@@ -498,8 +498,9 @@ bool Analysis::isSafeToStackAllocate(Instruction* Alloc) {
// the original allocation.
// That can only be true if it dominates the allocation.
// FIXME: To be more precise, it's also only true if it's then used after
// the original allocation instruction gets performed again, but
// how to check that?
// the original allocation instruction gets performed again (and
// the instruction generating the derived pointer doesn't), but how
// to check that?
if (!I->use_empty() && DT.dominates(I, Alloc))
return false;