6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-06-27 14:24:40 +00:00
Code Issues Projects Releases Wiki Activity

refactor some code, no functionality change.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50094 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
2008-04-22 06:36:15 +00:00
parent f29984f695
commit d38c14e6ed
1 changed files with 13 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
lib/Transforms/Scalar/JumpThreading.cpp
View File

@ -57,6 +57,8 @@ namespace {
bool runOnFunction(Function &F); bool runOnFunction(Function &F);
bool ThreadBlock(BasicBlock *BB); bool ThreadBlock(BasicBlock *BB);
void ThreadEdge(BasicBlock *BB, BasicBlock *PredBB, BasicBlock *SuccBB); void ThreadEdge(BasicBlock *BB, BasicBlock *PredBB, BasicBlock *SuccBB);
bool ProcessJumpOnPHI(PHINode *PN);
}; };
char JumpThreading::ID = 0; char JumpThreading::ID = 0;
RegisterPass<JumpThreading> X("jump-threading", "Jump Threading"); RegisterPass<JumpThreading> X("jump-threading", "Jump Threading");
@ -158,8 +160,17 @@ bool JumpThreading::ThreadBlock(BasicBlock *BB) {
// See if this is a phi node in the current block. // See if this is a phi node in the current block.
PHINode *PN = dyn_cast<PHINode>(Condition); PHINode *PN = dyn_cast<PHINode>(Condition);
if (!PN || PN->getParent() != BB) return false; if (PN && PN->getParent() == BB)
return ProcessJumpOnPHI(PN);
return false;
}
/// ProcessJumpOnPHI - We have a conditional branch of switch on a PHI node in
/// the current block. See if there are any simplifications we can do based on
/// inputs to the phi node.
///
bool JumpThreading::ProcessJumpOnPHI(PHINode *PN) {
// See if the phi node has any constant values. If so, we can determine where // See if the phi node has any constant values. If so, we can determine where
// the corresponding predecessor will branch. // the corresponding predecessor will branch.
unsigned PredNo = ~0U; unsigned PredNo = ~0U;
@ -177,6 +188,7 @@ bool JumpThreading::ThreadBlock(BasicBlock *BB) {
return false; return false;
// See if the cost of duplicating this block is low enough. // See if the cost of duplicating this block is low enough.
BasicBlock *BB = PN->getParent();
unsigned JumpThreadCost = getJumpThreadDuplicationCost(BB); unsigned JumpThreadCost = getJumpThreadDuplicationCost(BB);
if (JumpThreadCost > Threshold) { if (JumpThreadCost > Threshold) {
DOUT << " Not threading BB '" << BB->getNameStart() DOUT << " Not threading BB '" << BB->getNameStart()
@ -210,7 +222,6 @@ bool JumpThreading::ThreadBlock(BasicBlock *BB) {
".thr_comm", this); ".thr_comm", this);
} }
DOUT << " Threading edge from '" << PredBB->getNameStart() << "' to '" DOUT << " Threading edge from '" << PredBB->getNameStart() << "' to '"
<< SuccBB->getNameStart() << "' with cost: " << JumpThreadCost << SuccBB->getNameStart() << "' with cost: " << JumpThreadCost
<< ", across block:\n " << ", across block:\n "