Rename 'SValuator' to 'SValBuilder'. The new name
reflects what the class actually does.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@120605 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/SValBuilder.cpp b/lib/Checker/SValBuilder.cpp
new file mode 100644
index 0000000..8bc9594
--- /dev/null
+++ b/lib/Checker/SValBuilder.cpp
@@ -0,0 +1,169 @@
+// SValBuilder.cpp - Basic class for all SValBuilder implementations -*- C++ -*-
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines SValBuilder, the base class for all (complete) SValBuilder
+// implementations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Checker/PathSensitive/SValBuilder.h"
+#include "clang/Checker/PathSensitive/GRState.h"
+
+using namespace clang;
+
+
+SVal SValBuilder::EvalBinOp(const GRState *ST, BinaryOperator::Opcode Op,
+ SVal L, SVal R, QualType T) {
+
+ if (L.isUndef() || R.isUndef())
+ return UndefinedVal();
+
+ if (L.isUnknown() || R.isUnknown())
+ return UnknownVal();
+
+ if (isa<Loc>(L)) {
+ if (isa<Loc>(R))
+ return EvalBinOpLL(ST, Op, cast<Loc>(L), cast<Loc>(R), T);
+
+ return EvalBinOpLN(ST, Op, cast<Loc>(L), cast<NonLoc>(R), T);
+ }
+
+ if (isa<Loc>(R)) {
+ // Support pointer arithmetic where the addend is on the left
+ // and the pointer on the right.
+ assert(Op == BO_Add);
+
+ // Commute the operands.
+ return EvalBinOpLN(ST, Op, cast<Loc>(R), cast<NonLoc>(L), T);
+ }
+
+ return EvalBinOpNN(ST, Op, cast<NonLoc>(L), cast<NonLoc>(R), T);
+}
+
+DefinedOrUnknownSVal SValBuilder::EvalEQ(const GRState *ST,
+ DefinedOrUnknownSVal L,
+ DefinedOrUnknownSVal R) {
+ return cast<DefinedOrUnknownSVal>(EvalBinOp(ST, BO_EQ, L, R,
+ ValMgr.getContext().IntTy));
+}
+
+// FIXME: should rewrite according to the cast kind.
+SVal SValBuilder::EvalCast(SVal val, QualType castTy, QualType originalTy) {
+ if (val.isUnknownOrUndef() || castTy == originalTy)
+ return val;
+
+ ASTContext &C = ValMgr.getContext();
+
+ // For const casts, just propagate the value.
+ if (!castTy->isVariableArrayType() && !originalTy->isVariableArrayType())
+ if (C.hasSameUnqualifiedType(castTy, originalTy))
+ return val;
+
+ // Check for casts to real or complex numbers. We don't handle these at all
+ // right now.
+ if (castTy->isFloatingType() || castTy->isAnyComplexType())
+ return UnknownVal();
+
+ // Check for casts from integers to integers.
+ if (castTy->isIntegerType() && originalTy->isIntegerType())
+ return EvalCastNL(cast<NonLoc>(val), castTy);
+
+ // Check for casts from pointers to integers.
+ if (castTy->isIntegerType() && Loc::IsLocType(originalTy))
+ return EvalCastL(cast<Loc>(val), castTy);
+
+ // Check for casts from integers to pointers.
+ if (Loc::IsLocType(castTy) && originalTy->isIntegerType()) {
+ if (nonloc::LocAsInteger *LV = dyn_cast<nonloc::LocAsInteger>(&val)) {
+ if (const MemRegion *R = LV->getLoc().getAsRegion()) {
+ StoreManager &storeMgr = ValMgr.getStateManager().getStoreManager();
+ R = storeMgr.CastRegion(R, castTy);
+ return R ? SVal(loc::MemRegionVal(R)) : UnknownVal();
+ }
+ return LV->getLoc();
+ }
+ goto DispatchCast;
+ }
+
+ // Just pass through function and block pointers.
+ if (originalTy->isBlockPointerType() || originalTy->isFunctionPointerType()) {
+ assert(Loc::IsLocType(castTy));
+ return val;
+ }
+
+ // Check for casts from array type to another type.
+ if (originalTy->isArrayType()) {
+ // We will always decay to a pointer.
+ val = ValMgr.getStateManager().ArrayToPointer(cast<Loc>(val));
+
+ // Are we casting from an array to a pointer? If so just pass on
+ // the decayed value.
+ if (castTy->isPointerType())
+ return val;
+
+ // Are we casting from an array to an integer? If so, cast the decayed
+ // pointer value to an integer.
+ assert(castTy->isIntegerType());
+
+ // FIXME: Keep these here for now in case we decide soon that we
+ // need the original decayed type.
+ // QualType elemTy = cast<ArrayType>(originalTy)->getElementType();
+ // QualType pointerTy = C.getPointerType(elemTy);
+ return EvalCastL(cast<Loc>(val), castTy);
+ }
+
+ // Check for casts from a region to a specific type.
+ if (const MemRegion *R = val.getAsRegion()) {
+ // FIXME: We should handle the case where we strip off view layers to get
+ // to a desugared type.
+
+ if (!Loc::IsLocType(castTy)) {
+ // FIXME: There can be gross cases where one casts the result of a function
+ // (that returns a pointer) to some other value that happens to fit
+ // within that pointer value. We currently have no good way to
+ // model such operations. When this happens, the underlying operation
+ // is that the caller is reasoning about bits. Conceptually we are
+ // layering a "view" of a location on top of those bits. Perhaps
+ // we need to be more lazy about mutual possible views, even on an
+ // SVal? This may be necessary for bit-level reasoning as well.
+ return UnknownVal();
+ }
+
+ // We get a symbolic function pointer for a dereference of a function
+ // pointer, but it is of function type. Example:
+
+ // struct FPRec {
+ // void (*my_func)(int * x);
+ // };
+ //
+ // int bar(int x);
+ //
+ // int f1_a(struct FPRec* foo) {
+ // int x;
+ // (*foo->my_func)(&x);
+ // return bar(x)+1; // no-warning
+ // }
+
+ assert(Loc::IsLocType(originalTy) || originalTy->isFunctionType() ||
+ originalTy->isBlockPointerType());
+
+ StoreManager &storeMgr = ValMgr.getStateManager().getStoreManager();
+
+ // Delegate to store manager to get the result of casting a region to a
+ // different type. If the MemRegion* returned is NULL, this expression
+ // evaluates to UnknownVal.
+ R = storeMgr.CastRegion(R, castTy);
+ return R ? SVal(loc::MemRegionVal(R)) : UnknownVal();
+ }
+
+DispatchCast:
+ // All other cases.
+ return isa<Loc>(val) ? EvalCastL(cast<Loc>(val), castTy)
+ : EvalCastNL(cast<NonLoc>(val), castTy);
+}