+Pass *llvm::createAlwaysInlinerPass(bool InsertLifetime) {
+ return new AlwaysInliner(InsertLifetime);
+}
+
+/// \brief Minimal filter to detect invalid constructs for inlining.
+static bool isInlineViable(Function &F) {
+ bool ReturnsTwice =F.getFnAttributes().hasAttribute(Attributes::ReturnsTwice);
+ for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; ++BI) {
+ // Disallow inlining of functions which contain an indirect branch.
+ if (isa<IndirectBrInst>(BI->getTerminator()))
+ return false;
+
+ for (BasicBlock::iterator II = BI->begin(), IE = BI->end(); II != IE;
+ ++II) {
+ CallSite CS(II);
+ if (!CS)
+ continue;
+
+ // Disallow recursive calls.
+ if (&F == CS.getCalledFunction())
+ return false;
+
+ // Disallow calls which expose returns-twice to a function not previously
+ // attributed as such.
+ if (!ReturnsTwice && CS.isCall() &&
+ cast<CallInst>(CS.getInstruction())->canReturnTwice())
+ return false;
+ }
+ }
+
+ return true;
+}
+
+/// \brief Get the inline cost for the always-inliner.
+///
+/// The always inliner *only* handles functions which are marked with the
+/// attribute to force inlining. As such, it is dramatically simpler and avoids
+/// using the powerful (but expensive) inline cost analysis. Instead it uses
+/// a very simple and boring direct walk of the instructions looking for
+/// impossible-to-inline constructs.
+///
+/// Note, it would be possible to go to some lengths to cache the information
+/// computed here, but as we only expect to do this for relatively few and
+/// small functions which have the explicit attribute to force inlining, it is
+/// likely not worth it in practice.
+InlineCost AlwaysInliner::getInlineCost(CallSite CS) {
+ Function *Callee = CS.getCalledFunction();
+ // We assume indirect calls aren't calling an always-inline function.
+ if (!Callee) return InlineCost::getNever();
+
+ // We can't inline calls to external functions.
+ // FIXME: We shouldn't even get here.
+ if (Callee->isDeclaration()) return InlineCost::getNever();
+
+ // Return never for anything not marked as always inline.
+ if (!Callee->getFnAttributes().hasAttribute(Attributes::AlwaysInline))
+ return InlineCost::getNever();
+
+ // Do some minimal analysis to preclude non-viable functions.
+ if (!isInlineViable(*Callee))
+ return InlineCost::getNever();
+
+ // Otherwise, force inlining.
+ return InlineCost::getAlways();
+}
+
+// doInitialization - Initializes the vector of functions that have not