///
TerminatorInst *getTerminator();
const TerminatorInst *const getTerminator() const;
-
+
+ /// Returns a pointer to the first instructon in this block that is not a
+ /// PHINode instruction. When adding instruction to the beginning of the
+ /// basic block, they should be added before the returned value, not before
+ /// the first instruction, which might be PHI.
+ /// Returns 0 is there's no non-PHI instruction.
+ Instruction* getFirstNonPHI();
+
/// removeFromParent - This method unlinks 'this' from the containing
/// function, but does not delete it.
///
return dyn_cast<TerminatorInst>(&InstList.back());
}
+Instruction* BasicBlock::getFirstNonPHI()
+{
+ BasicBlock::iterator i = begin(), e = end();
+ // All valid basic blocks should have a terminator,
+ // which is not a PHINode. If we have invalid basic
+ // block we'll get assert when dereferencing past-the-end
+ // iterator.
+ while (isa<PHINode>(i)) ++i;
+ return &*i;
+}
+
void BasicBlock::dropAllReferences() {
for(iterator I = begin(), E = end(); I != E; ++I)
I->dropAllReferences();