Implement src:*=sanitize for UBSan

Author: qinkunbao

clang/lib/Basic/NoSanitizeList.cpp

@@ -44,7 +44,8 @@ bool NoSanitizeList::containsFunction(SanitizerMask Mask,
 
 bool NoSanitizeList::containsFile(SanitizerMask Mask, StringRef FileName,
                                   StringRef Category) const {
-  return SSCL->inSection(Mask, "src", FileName, Category);
+  bool allowList = SSCL->inSection(Mask, "src", FileName, "sanitize");
+  return SSCL->inSection(Mask, "src", FileName, Category) && !allowList;
 }
 
 bool NoSanitizeList::containsMainFile(SanitizerMask Mask, StringRef FileName,

clang/test/CodeGen/ubsan-src-ignorelist-category.test

@@ -0,0 +1,33 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsanitize=signed-integer-overflow -fsanitize-ignorelist=%t/src.ignorelist -emit-llvm %t/test1.c -o - | FileCheck %s -check-prefix=CHECK-ALLOWLIST
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsanitize=signed-integer-overflow -fsanitize-ignorelist=%t/src.ignorelist -emit-llvm %t/test2.c -o - | FileCheck %s -check-prefix=CHECK-IGNORELIST
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsanitize=signed-integer-overflow -fsanitize-ignorelist=%t/src.ignorelist.contradict -emit-llvm %t/test1.c -o - | FileCheck %s -check-prefix=CHECK-ALLOWLIST
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsanitize=signed-integer-overflow -fsanitize-ignorelist=%t/src.ignorelist.contradict -emit-llvm %t/test2.c -o - | FileCheck %s -check-prefix=CHECK-IGNORELIST
+
+
+// Verify ubsan only emits checks for files in the allowlist
+
+//--- src.ignorelist
+src:*
+src:*/test1.c=sanitize
+
+// If the same src appears within or across ignorelists with different categories the sanitize category takes precedence – regardless of order.
+//--- src.ignorelist.contradict
+src:*
+src:*/test1.c=sanitize
+src:*/test1.c
+
+//--- test1.c
+int add1(int a, int b) {
+// CHECK-ALLOWLIST: llvm.sadd.with.overflow.i32
+    return a+b;
+}
+
+//--- test2.c
+int add2(int a, int b) {
+// CHECK-IGNORELIST-NOT: llvm.sadd.with.overflow.i32
+    return a+b;
+}
+
+