[clang] [Clang][CodeGen] Emit “trap reasons” on UBSan traps (PR #145967)

[Shafik Yaghmour via cfe-commits]

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@@ -14,35 +14,66 @@
 #define LLVM_CLANG_LIB_CODEGEN_SANITIZER_HANDLER_H
 
 #define LIST_SANITIZER_CHECKS                                                  \
-  SANITIZER_CHECK(AddOverflow, add_overflow, 0)                                \
-  SANITIZER_CHECK(BuiltinUnreachable, builtin_unreachable, 0)                  \
-  SANITIZER_CHECK(CFICheckFail, cfi_check_fail, 0)                             \
-  SANITIZER_CHECK(DivremOverflow, divrem_overflow, 0)                          \
-  SANITIZER_CHECK(DynamicTypeCacheMiss, dynamic_type_cache_miss, 0)            \
-  SANITIZER_CHECK(FloatCastOverflow, float_cast_overflow, 0)                   \
-  SANITIZER_CHECK(FunctionTypeMismatch, function_type_mismatch, 0)             \
-  SANITIZER_CHECK(ImplicitConversion, implicit_conversion, 0)                  \
-  SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0)                          \
-  SANITIZER_CHECK(InvalidObjCCast, invalid_objc_cast, 0)                       \
-  SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0)                     \
-  SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
-  SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
-  SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
-  SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
-  SANITIZER_CHECK(NullabilityReturn, nullability_return, 1)                    \
-  SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
-  SANITIZER_CHECK(NonnullReturn, nonnull_return, 1)                            \
-  SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
-  SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0)                        \
-  SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0)                    \
-  SANITIZER_CHECK(SubOverflow, sub_overflow, 0)                                \
-  SANITIZER_CHECK(TypeMismatch, type_mismatch, 1)                              \
-  SANITIZER_CHECK(AlignmentAssumption, alignment_assumption, 0)                \
-  SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)              \
-  SANITIZER_CHECK(BoundsSafety, bounds_safety, 0)
+  SANITIZER_CHECK(AddOverflow, add_overflow, 0, "Integer addition overflowed") \
----------------
shafik wrote:

Is this singed, unsigned or both? UBSan has both but I don't see two versions here, it is curious there is a sub overflow, which is not specifically delineated via `-fsanitize`, may be worth clarifying. 

https://github.com/llvm/llvm-project/pull/145967