[PATCH] D31029: [analyzer] Fix logical not for pointers with different bit width

[Daniel Marjamäki via Phabricator via cfe-commits]

danielmarjamaki updated this revision to Diff 92773.
danielmarjamaki added a comment.

Added a testcase that will crash without the fix. Used the amdgcn target as that happens to use different pointer bit widths for different address spaces.

Updated the comment. I am not good at english so I hope the grammar is ok.


Repository:
  rL LLVM

https://reviews.llvm.org/D31029

Files:
  include/clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h
  include/clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h
  lib/StaticAnalyzer/Core/ExprEngineC.cpp
  test/Analysis/ptr.cl


Index: test/Analysis/ptr.cl
===================================================================
--- test/Analysis/ptr.cl
+++ test/Analysis/ptr.cl
@@ -0,0 +1,10 @@
+// RUN: %clang_analyze_cc1 -triple amdgcn-unknown-unknown -target-cpu verde -analyze -analyzer-checker=core %s
+
+#define __cm __attribute__((address_space(256)))
+
+// Don't crash when pointer bit-widths are different for different address spaces
+void dontCrash(void) {
+  __cm void *cm_p = 0;
+  if (!cm_p)
+    (void)cm_p;
+}
Index: lib/StaticAnalyzer/Core/ExprEngineC.cpp
===================================================================
--- lib/StaticAnalyzer/Core/ExprEngineC.cpp
+++ lib/StaticAnalyzer/Core/ExprEngineC.cpp
@@ -980,10 +980,9 @@
           //    transfer functions as "0 == E".
           SVal Result;
           if (Optional<Loc> LV = V.getAs<Loc>()) {
-            Loc X = svalBuilder.makeNull();
+            Loc X = svalBuilder.makeNullWithType(Ex->getType());
             Result = evalBinOp(state, BO_EQ, *LV, X, U->getType());
-          }
-          else if (Ex->getType()->isFloatingType()) {
+          } else if (Ex->getType()->isFloatingType()) {
             // FIXME: handle floating point types.
             Result = UnknownVal();
           } else {
Index: include/clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h
===================================================================
--- include/clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h
+++ include/clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h
@@ -310,10 +310,15 @@
     return nonloc::ConcreteInt(BasicVals.getTruthValue(b));
   }
 
-  Loc makeNull() {
-    return loc::ConcreteInt(BasicVals.getZeroWithPtrWidth());
+  /// Create NULL pointer, with proper pointer bit-width for given address
+  /// space.
+  /// \param type pointer type.
+  Loc makeNullWithType(QualType type) {
+    return loc::ConcreteInt(BasicVals.getZeroWithTypeSize(type));
   }
 
+  Loc makeNull() { return loc::ConcreteInt(BasicVals.getZeroWithPtrWidth()); }
+
   Loc makeLoc(SymbolRef sym) {
     return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
   }
Index: include/clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h
===================================================================
--- include/clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h
+++ include/clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h
@@ -176,7 +176,12 @@
     return getValue(X);
   }
 
-  inline const llvm::APSInt& getZeroWithPtrWidth(bool isUnsigned = true) {
+  inline const llvm::APSInt &getZeroWithTypeSize(QualType T,
+                                                 bool isUnsigned = true) {
+    return getValue(0, Ctx.getTypeSize(T), isUnsigned);
+  }
+
+  inline const llvm::APSInt &getZeroWithPtrWidth(bool isUnsigned = true) {
     return getValue(0, Ctx.getTypeSize(Ctx.VoidPtrTy), isUnsigned);
   }
 


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