1 //===- InlineAlways.cpp - Code to inline always_inline functions ----------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements a custom inliner that handles only functions that
11 // are marked as "always inline".
13 //===----------------------------------------------------------------------===//
15 #define DEBUG_TYPE "inline"
16 #include "llvm/CallingConv.h"
17 #include "llvm/Instructions.h"
18 #include "llvm/IntrinsicInst.h"
19 #include "llvm/Module.h"
20 #include "llvm/Type.h"
21 #include "llvm/Analysis/CallGraph.h"
22 #include "llvm/Analysis/InlineCost.h"
23 #include "llvm/Support/CallSite.h"
24 #include "llvm/Transforms/IPO.h"
25 #include "llvm/Transforms/IPO/InlinerPass.h"
26 #include "llvm/ADT/SmallPtrSet.h"
32 // AlwaysInliner only inlines functions that are mark as "always inline".
33 class AlwaysInliner : public Inliner {
34 // Functions that are never inlined
35 SmallPtrSet<const Function*, 16> NeverInline;
36 InlineCostAnalyzer CA;
38 // Use extremely low threshold.
39 AlwaysInliner() : Inliner(&ID, -2000000000) {}
40 static char ID; // Pass identification, replacement for typeid
41 InlineCost getInlineCost(CallSite CS) {
42 return CA.getInlineCost(CS, NeverInline);
44 float getInlineFudgeFactor(CallSite CS) {
45 return CA.getInlineFudgeFactor(CS);
47 void resetCachedCostInfo(Function *Caller) {
48 return CA.resetCachedCostInfo(Caller);
50 virtual bool doFinalization(CallGraph &CG) {
51 return removeDeadFunctions(CG, &NeverInline);
53 virtual bool doInitialization(CallGraph &CG);
57 char AlwaysInliner::ID = 0;
58 static RegisterPass<AlwaysInliner>
59 X("always-inline", "Inliner for always_inline functions");
61 Pass *llvm::createAlwaysInlinerPass() { return new AlwaysInliner(); }
63 // doInitialization - Initializes the vector of functions that have not
64 // been annotated with the "always inline" attribute.
65 bool AlwaysInliner::doInitialization(CallGraph &CG) {
66 Module &M = CG.getModule();
68 for (Module::iterator I = M.begin(), E = M.end();
70 if (!I->isDeclaration() && !I->hasFnAttr(Attribute::AlwaysInline))
71 NeverInline.insert(I);