104 lines
3.5 KiB
C++
104 lines
3.5 KiB
C++
#include "AliasAnalysisSummary.h"
|
|
#include "llvm/IR/Argument.h"
|
|
#include "llvm/IR/Type.h"
|
|
#include "llvm/Support/Compiler.h"
|
|
|
|
namespace llvm {
|
|
namespace cflaa {
|
|
|
|
namespace {
|
|
const unsigned AttrEscapedIndex = 0;
|
|
const unsigned AttrUnknownIndex = 1;
|
|
const unsigned AttrGlobalIndex = 2;
|
|
const unsigned AttrCallerIndex = 3;
|
|
const unsigned AttrFirstArgIndex = 4;
|
|
const unsigned AttrLastArgIndex = NumAliasAttrs;
|
|
const unsigned AttrMaxNumArgs = AttrLastArgIndex - AttrFirstArgIndex;
|
|
|
|
// It would be *slightly* prettier if we changed these to AliasAttrs, but it
|
|
// seems that both GCC and MSVC emit dynamic initializers for const bitsets.
|
|
using AliasAttr = unsigned;
|
|
const AliasAttr AttrNone = 0;
|
|
const AliasAttr AttrEscaped = 1 << AttrEscapedIndex;
|
|
const AliasAttr AttrUnknown = 1 << AttrUnknownIndex;
|
|
const AliasAttr AttrGlobal = 1 << AttrGlobalIndex;
|
|
const AliasAttr AttrCaller = 1 << AttrCallerIndex;
|
|
const AliasAttr ExternalAttrMask = AttrEscaped | AttrUnknown | AttrGlobal;
|
|
}
|
|
|
|
AliasAttrs getAttrNone() { return AttrNone; }
|
|
|
|
AliasAttrs getAttrUnknown() { return AttrUnknown; }
|
|
bool hasUnknownAttr(AliasAttrs Attr) { return Attr.test(AttrUnknownIndex); }
|
|
|
|
AliasAttrs getAttrCaller() { return AttrCaller; }
|
|
bool hasCallerAttr(AliasAttrs Attr) { return Attr.test(AttrCaller); }
|
|
bool hasUnknownOrCallerAttr(AliasAttrs Attr) {
|
|
return Attr.test(AttrUnknownIndex) || Attr.test(AttrCallerIndex);
|
|
}
|
|
|
|
AliasAttrs getAttrEscaped() { return AttrEscaped; }
|
|
bool hasEscapedAttr(AliasAttrs Attr) { return Attr.test(AttrEscapedIndex); }
|
|
|
|
static AliasAttr argNumberToAttr(unsigned ArgNum) {
|
|
if (ArgNum >= AttrMaxNumArgs)
|
|
return AttrUnknown;
|
|
// N.B. MSVC complains if we use `1U` here, since AliasAttr' ctor takes
|
|
// an unsigned long long.
|
|
return AliasAttr(1ULL << (ArgNum + AttrFirstArgIndex));
|
|
}
|
|
|
|
AliasAttrs getGlobalOrArgAttrFromValue(const Value &Val) {
|
|
if (isa<GlobalValue>(Val))
|
|
return AttrGlobal;
|
|
|
|
if (auto *Arg = dyn_cast<Argument>(&Val))
|
|
// Only pointer arguments should have the argument attribute,
|
|
// because things can't escape through scalars without us seeing a
|
|
// cast, and thus, interaction with them doesn't matter.
|
|
if (!Arg->hasNoAliasAttr() && Arg->getType()->isPointerTy())
|
|
return argNumberToAttr(Arg->getArgNo());
|
|
return AttrNone;
|
|
}
|
|
|
|
bool isGlobalOrArgAttr(AliasAttrs Attr) {
|
|
return Attr.reset(AttrEscapedIndex)
|
|
.reset(AttrUnknownIndex)
|
|
.reset(AttrCallerIndex)
|
|
.any();
|
|
}
|
|
|
|
AliasAttrs getExternallyVisibleAttrs(AliasAttrs Attr) {
|
|
return Attr & AliasAttrs(ExternalAttrMask);
|
|
}
|
|
|
|
Optional<InstantiatedValue> instantiateInterfaceValue(InterfaceValue IValue,
|
|
CallSite CS) {
|
|
auto Index = IValue.Index;
|
|
auto Value = (Index == 0) ? CS.getInstruction() : CS.getArgument(Index - 1);
|
|
if (Value->getType()->isPointerTy())
|
|
return InstantiatedValue{Value, IValue.DerefLevel};
|
|
return None;
|
|
}
|
|
|
|
Optional<InstantiatedRelation>
|
|
instantiateExternalRelation(ExternalRelation ERelation, CallSite CS) {
|
|
auto From = instantiateInterfaceValue(ERelation.From, CS);
|
|
if (!From)
|
|
return None;
|
|
auto To = instantiateInterfaceValue(ERelation.To, CS);
|
|
if (!To)
|
|
return None;
|
|
return InstantiatedRelation{*From, *To, ERelation.Offset};
|
|
}
|
|
|
|
Optional<InstantiatedAttr> instantiateExternalAttribute(ExternalAttribute EAttr,
|
|
CallSite CS) {
|
|
auto Value = instantiateInterfaceValue(EAttr.IValue, CS);
|
|
if (!Value)
|
|
return None;
|
|
return InstantiatedAttr{*Value, EAttr.Attr};
|
|
}
|
|
}
|
|
}
|