Analysis: Move llvm::getConstantRangeFromMetadata to IR library.
We're about to start using it there.
Differential Revision: https://reviews.llvm.org/D25877
llvm-svn: 284865
diff --git a/llvm/lib/IR/ConstantRange.cpp b/llvm/lib/IR/ConstantRange.cpp
index 225eb5e..e188c80 100644
--- a/llvm/lib/IR/ConstantRange.cpp
+++ b/llvm/lib/IR/ConstantRange.cpp
@@ -922,3 +922,25 @@
LLVM_DUMP_METHOD void ConstantRange::dump() const {
print(dbgs());
}
+
+ConstantRange llvm::getConstantRangeFromMetadata(const MDNode &Ranges) {
+ const unsigned NumRanges = Ranges.getNumOperands() / 2;
+ assert(NumRanges >= 1 && "Must have at least one range!");
+ assert(Ranges.getNumOperands() % 2 == 0 && "Must be a sequence of pairs");
+
+ auto *FirstLow = mdconst::extract<ConstantInt>(Ranges.getOperand(0));
+ auto *FirstHigh = mdconst::extract<ConstantInt>(Ranges.getOperand(1));
+
+ ConstantRange CR(FirstLow->getValue(), FirstHigh->getValue());
+
+ for (unsigned i = 1; i < NumRanges; ++i) {
+ auto *Low = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0));
+ auto *High = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1));
+
+ // Note: unionWith will potentially create a range that contains values not
+ // contained in any of the original N ranges.
+ CR = CR.unionWith(ConstantRange(Low->getValue(), High->getValue()));
+ }
+
+ return CR;
+}