1//===- LibCallSemantics.cpp - Describe library semantics ------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements interfaces that can be used to describe language
11// specific runtime library interfaces (e.g. libc, libm, etc) to LLVM
12// optimizers.
13//
14//===----------------------------------------------------------------------===//
15
16#include "llvm/Analysis/LibCallSemantics.h"
17#include "llvm/ADT/StringMap.h"
18#include "llvm/IR/Function.h"
19using namespace llvm;
20
21/// getMap - This impl pointer in ~LibCallInfo is actually a StringMap.  This
22/// helper does the cast.
23static StringMap<const LibCallFunctionInfo*> *getMap(void *Ptr) {
24  return static_cast<StringMap<const LibCallFunctionInfo*> *>(Ptr);
25}
26
27LibCallInfo::~LibCallInfo() {
28  delete getMap(Impl);
29}
30
31const LibCallLocationInfo &LibCallInfo::getLocationInfo(unsigned LocID) const {
32  // Get location info on the first call.
33  if (NumLocations == 0)
34    NumLocations = getLocationInfo(Locations);
35
36  assert(LocID < NumLocations && "Invalid location ID!");
37  return Locations[LocID];
38}
39
40
41/// getFunctionInfo - Return the LibCallFunctionInfo object corresponding to
42/// the specified function if we have it.  If not, return null.
43const LibCallFunctionInfo *
44LibCallInfo::getFunctionInfo(const Function *F) const {
45  StringMap<const LibCallFunctionInfo*> *Map = getMap(Impl);
46
47  /// If this is the first time we are querying for this info, lazily construct
48  /// the StringMap to index it.
49  if (!Map) {
50    Impl = Map = new StringMap<const LibCallFunctionInfo*>();
51
52    const LibCallFunctionInfo *Array = getFunctionInfoArray();
53    if (!Array) return nullptr;
54
55    // We now have the array of entries.  Populate the StringMap.
56    for (unsigned i = 0; Array[i].Name; ++i)
57      (*Map)[Array[i].Name] = Array+i;
58  }
59
60  // Look up this function in the string map.
61  return Map->lookup(F->getName());
62}
63
64