Add the CompactionTableIsEmpty function so that we can determine if a
CompactionTable really needs to be emitted. This is not a straight forward
computation, hence the need for a member function here.
llvm-svn: 16062
diff --git a/llvm/lib/Bytecode/Writer/SlotCalculator.cpp b/llvm/lib/Bytecode/Writer/SlotCalculator.cpp
index 75fb418..2656edd 100644
--- a/llvm/lib/Bytecode/Writer/SlotCalculator.cpp
+++ b/llvm/lib/Bytecode/Writer/SlotCalculator.cpp
@@ -622,6 +622,32 @@
}
}
+/// Determine if the compaction table is actually empty. Because the
+/// compaction table always includes the primitive type planes, we
+/// can't just check getCompactionTable().size() because it will never
+/// be zero. Furthermore, the ModuleLevel factors into whether a given
+/// plane is empty or not. This function does the necessary computation
+/// to determine if its actually empty.
+bool SlotCalculator::CompactionTableIsEmpty() const {
+ // Check a degenerate case, just in case.
+ if (CompactionTable.size() == 0) return true;
+
+ // Check each plane
+ for (unsigned i = 0, e = CompactionTable.size(); i < e; ++i) {
+ // If the plane is not empty
+ if (!CompactionTable[i].empty()) {
+ // If the module level is non-zero then at least the
+ // first element of the plane is valid and therefore not empty.
+ unsigned End = getModuleLevel(i);
+ if (End != 0)
+ return false;
+ }
+ }
+ // All the compaction table planes are empty so the table is
+ // considered empty too.
+ return true;
+}
+
int SlotCalculator::getSlot(const Value *V) const {
// If there is a CompactionTable active...
if (!CompactionNodeMap.empty()) {