[ubsan] Diagnose invalid uses of builtins (compiler-rt)

Differential Revision: https://reviews.llvm.org/D34591

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@309461 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 42 insertions, 0 deletions

diff --git a/lib/ubsan/ubsan_checks.inc b/lib/ubsan/ubsan_checks.inc
index 0a87e6e8e..73c693632 100644
--- a/lib/ubsan/ubsan_checks.inc
+++ b/lib/ubsan/ubsan_checks.inc
@@ -29,6 +29,7 @@ UBSAN_CHECK(UnsignedIntegerOverflow, "unsigned-integer-overflow",
 UBSAN_CHECK(IntegerDivideByZero, "integer-divide-by-zero",
             "integer-divide-by-zero")
 UBSAN_CHECK(FloatDivideByZero, "float-divide-by-zero", "float-divide-by-zero")
+UBSAN_CHECK(InvalidBuiltin, "invalid-builtin-use", "invalid-builtin-use")
 UBSAN_CHECK(InvalidShiftBase, "invalid-shift-base", "shift-base")
 UBSAN_CHECK(InvalidShiftExponent, "invalid-shift-exponent", "shift-exponent")
 UBSAN_CHECK(OutOfBoundsIndex, "out-of-bounds-index", "bounds")
diff --git a/lib/ubsan/ubsan_handlers.cc b/lib/ubsan/ubsan_handlers.cc
index 75a4490a1..06438a5d3 100644
--- a/lib/ubsan/ubsan_handlers.cc
+++ b/lib/ubsan/ubsan_handlers.cc
@@ -437,6 +437,30 @@ void __ubsan::__ubsan_handle_load_invalid_value_abort(InvalidValueData *Data,
   Die();
 }
 
+static void handleInvalidBuiltin(InvalidBuiltinData *Data, ReportOptions Opts) {
+  SourceLocation Loc = Data->Loc.acquire();
+  ErrorType ET = ErrorType::InvalidBuiltin;
+
+  if (ignoreReport(Loc, Opts, ET))
+    return;
+
+  ScopedReport R(Opts, Loc, ET);
+
+  Diag(Loc, DL_Error,
+       "passing zero to %0, which is not a valid argument")
+    << ((Data->Kind == BCK_CTZPassedZero) ? "ctz()" : "clz()");
+}
+
+void __ubsan::__ubsan_handle_invalid_builtin(InvalidBuiltinData *Data) {
+  GET_REPORT_OPTIONS(true);
+  handleInvalidBuiltin(Data, Opts);
+}
+void __ubsan::__ubsan_handle_invalid_builtin_abort(InvalidBuiltinData *Data) {
+  GET_REPORT_OPTIONS(true);
+  handleInvalidBuiltin(Data, Opts);
+  Die();
+}
+
 static void handleFunctionTypeMismatch(FunctionTypeMismatchData *Data,
                                        ValueHandle Function,
                                        ReportOptions Opts) {
diff --git a/lib/ubsan/ubsan_handlers.h b/lib/ubsan/ubsan_handlers.h
index 796321b81..5a9e902ce 100644
--- a/lib/ubsan/ubsan_handlers.h
+++ b/lib/ubsan/ubsan_handlers.h
@@ -122,6 +122,21 @@ struct InvalidValueData {
 /// \brief Handle a load of an invalid value for the type.
 RECOVERABLE(load_invalid_value, InvalidValueData *Data, ValueHandle Val)
 
+/// Known builtin check kinds.
+/// Keep in sync with the enum of the same name in CodeGenFunction.h
+enum BuiltinCheckKind : unsigned char {
+  BCK_CTZPassedZero,
+  BCK_CLZPassedZero,
+};
+
+struct InvalidBuiltinData {
+  SourceLocation Loc;
+  unsigned char Kind;
+};
+
+/// Handle a builtin called in an invalid way.
+RECOVERABLE(invalid_builtin, InvalidBuiltinData *Data)
+
 struct FunctionTypeMismatchData {
   SourceLocation Loc;
   const TypeDescriptor &Type;
diff --git a/lib/ubsan/ubsan_interface.inc b/lib/ubsan/ubsan_interface.inc
index a69ca57cd..4c8f92e4f 100644
--- a/lib/ubsan/ubsan_interface.inc
+++ b/lib/ubsan/ubsan_interface.inc
@@ -19,6 +19,8 @@ INTERFACE_FUNCTION(__ubsan_handle_float_cast_overflow)
 INTERFACE_FUNCTION(__ubsan_handle_float_cast_overflow_abort)
 INTERFACE_FUNCTION(__ubsan_handle_function_type_mismatch)
 INTERFACE_FUNCTION(__ubsan_handle_function_type_mismatch_abort)
+INTERFACE_FUNCTION(__ubsan_handle_invalid_builtin)
+INTERFACE_FUNCTION(__ubsan_handle_invalid_builtin_abort)
 INTERFACE_FUNCTION(__ubsan_handle_load_invalid_value)
 INTERFACE_FUNCTION(__ubsan_handle_load_invalid_value_abort)
 INTERFACE_FUNCTION(__ubsan_handle_missing_return)