maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

Implement trivial sinking for load instructions. This causes us to sink 567 loads in spec 

llvm-svn: 18692
This commit is contained in:
Chris Lattner 2004-12-09 07:14:34 +00:00
parent 6225146f20
commit f17a2fb849
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
llvm/lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -4206,7 +4206,17 @@ static bool TryToSinkInstruction(Instruction *I, BasicBlock *DestBlock) {
if (isa<AllocaInst>(I) && I->getParent() == &DestBlock->getParent()->front())
return false;
if (isa<LoadInst>(I)) return false;
// We can only sink load instructions if there is nothing between the load and
// the end of block that could change the value.
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
if (LI->isVolatile()) return false; // Don't sink volatile loads.
for (BasicBlock::iterator Scan = LI, E = LI->getParent()->end();
Scan != E; ++Scan)
if (Scan->mayWriteToMemory())
return false;
std::cerr << "SUNK LOAD: " << *LI;
}
BasicBlock::iterator InsertPos = DestBlock->begin();
while (isa<PHINode>(InsertPos)) ++InsertPos;