1 //===- InlineSimple.cpp - Code to perform simple function inlining --------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements bottom-up inlining of functions into callees.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "inline"
15 #include "llvm/CallingConv.h"
16 #include "llvm/Instructions.h"
17 #include "llvm/IntrinsicInst.h"
18 #include "llvm/Module.h"
19 #include "llvm/Type.h"
20 #include "llvm/Analysis/CallGraph.h"
21 #include "llvm/Support/CallSite.h"
22 #include "llvm/Support/Compiler.h"
23 #include "llvm/Transforms/IPO.h"
24 #include "llvm/Transforms/IPO/InlinerPass.h"
25 #include "llvm/Transforms/Utils/InlineCost.h"
32 class VISIBILITY_HIDDEN SimpleInliner : public Inliner {
33 std::set<const Function*> NeverInline; // Functions that are never inlined
34 InlineCostAnalyzer CA;
36 SimpleInliner() : Inliner(&ID) {}
37 static char ID; // Pass identification, replacement for typeid
38 int getInlineCost(CallSite CS) {
39 return CA.getInlineCost(CS, NeverInline);
41 virtual bool doInitialization(CallGraph &CG);
43 char SimpleInliner::ID = 0;
44 RegisterPass<SimpleInliner> X("inline", "Function Integration/Inlining");
47 Pass *llvm::createFunctionInliningPass() { return new SimpleInliner(); }
49 // doInitialization - Initializes the vector of functions that have been
50 // annotated with the noinline attribute.
51 bool SimpleInliner::doInitialization(CallGraph &CG) {
53 Module &M = CG.getModule();
56 GlobalVariable *GV = M.getNamedGlobal("llvm.noinline");
61 const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
66 // Iterate over each element and add to the NeverInline set
67 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
70 const Constant *Elt = InitList->getOperand(i);
72 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Elt))
73 if (CE->getOpcode() == Instruction::BitCast)
74 Elt = CE->getOperand(0);
76 // Insert into set of functions to never inline
77 if (const Function *F = dyn_cast<Function>(Elt))
78 NeverInline.insert(F);