Split into two passes. Now there is the general loop extractor, usable on
the command line, and the single loop extractor, usable by bugpoint
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12390 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/IPO/LoopExtractor.cpp b/lib/Transforms/IPO/LoopExtractor.cpp
index f0d79e1..ce4d0f7 100644
--- a/lib/Transforms/IPO/LoopExtractor.cpp
+++ b/lib/Transforms/IPO/LoopExtractor.cpp
@@ -23,8 +23,14 @@
using namespace llvm;
namespace {
- // FIXME: PassManager should allow Module passes to require FunctionPasses
+ // FIXME: This is not a function pass, but the PassManager doesn't allow
+ // Module passes to require FunctionPasses, so we can't get loop info if we're
+ // not a function pass.
struct LoopExtractor : public FunctionPass {
+ unsigned NumLoops;
+
+ LoopExtractor(unsigned numLoops = ~0) : NumLoops(numLoops) {}
+
virtual bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
@@ -35,6 +41,14 @@
RegisterOpt<LoopExtractor>
X("loop-extract", "Extract loops into new functions");
+
+ /// SingleLoopExtractor - For bugpoint.
+ struct SingleLoopExtractor : public LoopExtractor {
+ SingleLoopExtractor() : LoopExtractor(1) {}
+ };
+
+ RegisterOpt<SingleLoopExtractor>
+ Y("loop-extract-single", "Extract at most one loop into a new function");
} // End anonymous namespace
bool LoopExtractor::runOnFunction(Function &F) {
@@ -47,14 +61,18 @@
bool Changed = false;
// Try to move each loop out of the code into separate function
- for (LoopInfo::iterator i = LI.begin(), e = LI.end(); i != e; ++i)
+ for (LoopInfo::iterator i = LI.begin(), e = LI.end(); i != e; ++i) {
+ if (NumLoops == 0) return Changed;
+ --NumLoops;
Changed |= (ExtractLoop(*i) != 0);
+ }
return Changed;
}
-/// createLoopExtractorPass
-///
-Pass* llvm::createLoopExtractorPass() {
- return new LoopExtractor();
+// createSingleLoopExtractorPass - This pass extracts one natural loop from the
+// program into a function if it can. This is used by bugpoint.
+//
+Pass *llvm::createSingleLoopExtractorPass() {
+ return new SingleLoopExtractor();
}