[analyzer] Fix assertion in simplifySymbolCast

[martong]

Summary

Added a new test code that fails an assertion in the baseline.
That is because getAPSIntType works only with integral types.

[martong]

Ping

[steakhal]

Oh I forgot to submit my review. My bad. Please investigate why we have two double casts there.

clang/lib/StaticAnalyzer/Core/SValBuilder.cpp

1082

Well, I would expect the same, but crosscheck this with the actual dump.

clang/test/Analysis/produce-symbolcast_x86.cpp

16

Place here a FIXME that we should not have two double casts.

[martong]

• Rebase on dependent patch

[martong]

clang/lib/StaticAnalyzer/Core/SValBuilder.cpp

1082

Please elaborate.

clang/test/Analysis/produce-symbolcast_x86.cpp

16

The (double)(double) problem is handled in the parent patch. Please check that out.

[steakhal]

LGTM

clang/lib/StaticAnalyzer/Core/SValBuilder.cpp

1082

nvm

clang/test/Analysis/produce-symbolcast_x86.cpp

16

Yeey, awesome!

clang/lib/StaticAnalyzer/Core/SValBuilder.cpp

if (T == CastTy)
     return V;
 
   if (!isa<SymbolCast>(SE))
     return makeNonLoc(SE, T, CastTy);
 
   SymbolRef RootSym = cast<SymbolCast>(SE)->getOperand();
   QualType RT = RootSym->getType().getCanonicalType();
 
+  // FIXME support cast from non-integers.
+  // E.g (char)(double)(double x) -> (char)(double x)
+  if (!RT->isIntegralOrEnumerationType())
+    return makeNonLoc(SE, T, CastTy);
+
   BasicValueFactory &BVF = getBasicValueFactory();
   APSIntType CTy = BVF.getAPSIntType(CastTy);
   APSIntType TTy = BVF.getAPSIntType(T);
 
   const auto WC = CTy.getBitWidth();
   const auto WT = TTy.getBitWidth();
 
   if (WC <= WT) {

clang/test/Analysis/produce-symbolcast_x86.cpp

 // RUN: %clang_analyze_cc1 -triple i386-pc-linux-gnu -analyzer-checker=debug.ExprInspection -analyzer-config support-symbolic-integer-casts=true -verify %s
 
 using uchar = unsigned char;
 using schar = signed char;
 using ushort = unsigned short;
 using uint = unsigned int;
 using ulong = unsigned long;
 using llong = long long;
 using ullong = unsigned long long;
 
 template <typename T>
 void clang_analyzer_dump(T);
 
+void test_double(int n) {
+  double D = n / 30;
+  clang_analyzer_dump(D); // expected-warning{{(double) ((double) ((reg_$0<int n>) / 30))}}
+  char C = D;
+  clang_analyzer_dump(C); // expected-warning{{(char) ((double) ((double) ((reg_$0<int n>) / 30)))}}
+  int I = C; // assertion should not fail here!
+  clang_analyzer_dump(I); // expected-warning{{(int) ((char) ((double) ((double) ((reg_$0<int n>) / 30))))}}
+}
+
 void test_schar(schar x) {
   clang_analyzer_dump(x); // expected-warning{{reg_$0<schar x>}}
 
   clang_analyzer_dump((schar)x);  // expected-warning{{reg_$0<schar x>}}
   clang_analyzer_dump((char)x);   // expected-warning{{(char) (reg_$0<schar x>)}}
   clang_analyzer_dump((short)x);  // expected-warning{{(short) (reg_$0<schar x>)}}
   clang_analyzer_dump((int)x);    // expected-warning{{(int) (reg_$0<schar x>)}}
   clang_analyzer_dump((long)x);   // expected-warning{{(long) (reg_$0<schar x>)}}