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One more place to skip debug info. 

llvm-svn: 67811
This commit is contained in:
Dale Johannesen 2009-03-27 01:13:37 +00:00
parent db65737b1c
commit 4026b041ce
1 changed files with 14 additions and 7 deletions
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21
llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
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@ -145,10 +145,11 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
return EverMadeChange; return EverMadeChange;
} }
/// EliminateMostlyEmptyBlocks - eliminate blocks that contain only PHI nodes /// EliminateMostlyEmptyBlocks - eliminate blocks that contain only PHI nodes,
/// and an unconditional branch. Passes before isel (e.g. LSR/loopsimplify) /// debug info directives, and an unconditional branch. Passes before isel
/// often split edges in ways that are non-optimal for isel. Start by /// (e.g. LSR/loopsimplify) often split edges in ways that are non-optimal for
/// eliminating these blocks so we can split them the way we want them. /// isel. Start by eliminating these blocks so we can split them the way we
/// want them.
bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) { bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
bool MadeChange = false; bool MadeChange = false;
// Note that this intentionally skips the entry block. // Note that this intentionally skips the entry block.
@ -160,12 +161,18 @@ bool CodeGenPrepare::EliminateMostlyEmptyBlocks(Function &F) {
if (!BI || !BI->isUnconditional()) if (!BI || !BI->isUnconditional())
continue; continue;
// If the instruction before the branch isn't a phi node, then other stuff // If the instruction before the branch (skipping debug info) isn't a phi
// is happening here. // node, then other stuff is happening here.
BasicBlock::iterator BBI = BI; BasicBlock::iterator BBI = BI;
if (BBI != BB->begin()) { if (BBI != BB->begin()) {
--BBI; --BBI;
if (!isa<PHINode>(BBI)) continue; while (isa<DbgInfoIntrinsic>(BBI)) {
if (BBI == BB->begin())
break;
--BBI;
}
if (!isa<DbgInfoIntrinsic>(BBI) && !isa<PHINode>(BBI))
continue;
} }
// Do not break infinite loops. // Do not break infinite loops.