[ubsan] Use pass_object_size info in bounds checks
Teach UBSan's bounds check to opportunistically use pass_object_size
information to check array accesses.
rdar://33272922
llvm-svn: 320128
diff --git a/clang/test/CodeGen/ubsan-pass-object-size.c b/clang/test/CodeGen/ubsan-pass-object-size.c
new file mode 100644
index 0000000..67970d2
--- /dev/null
+++ b/clang/test/CodeGen/ubsan-pass-object-size.c
@@ -0,0 +1,69 @@
+// RUN: %clang_cc1 %s -emit-llvm -w -triple x86_64-apple-darwin10 -fsanitize=array-bounds -o - | FileCheck %s
+
+// CHECK-LABEL: define i32 @foo(
+int foo(int *const p __attribute__((pass_object_size(0))), int n) {
+ int x = (p)[n];
+
+ // CHECK: [[SIZE_ALLOCA:%.*]] = alloca i64, align 8
+ // CHECK: store i64 %{{.*}}, i64* [[SIZE_ALLOCA]], align 8
+ // CHECK: [[LOAD_SIZE:%.*]] = load i64, i64* [[SIZE_ALLOCA]], align 8, !nosanitize
+ // CHECK-NEXT: [[SCALED_SIZE:%.*]] = udiv i64 [[LOAD_SIZE]], 4, !nosanitize
+ // CHECK-NEXT: [[SEXT_N:%.*]] = sext i32 %{{.*}} to i64, !nosanitize
+ // CHECK-NEXT: [[ICMP:%.*]] = icmp ult i64 [[SEXT_N]], [[SCALED_SIZE]], !nosanitize
+ // CHECK-NEXT: br i1 [[ICMP]], {{.*}} !nosanitize
+ // CHECK: __ubsan_handle_out_of_bounds
+
+ {
+ int **p = &p; // Shadow the parameter. The pass_object_size info is lost.
+ // CHECK-NOT: __ubsan_handle_out_of_bounds
+ x = *p[n];
+ }
+
+ // CHECK: ret i32
+ return x;
+}
+
+typedef struct {} ZeroSizedType;
+
+// CHECK-LABEL: define void @bar(
+ZeroSizedType bar(ZeroSizedType *const p __attribute__((pass_object_size(0))), int n) {
+ // CHECK-NOT: __ubsan_handle_out_of_bounds
+ // CHECK: ret void
+ return p[n];
+}
+
+// CHECK-LABEL: define i32 @baz(
+int baz(int *const p __attribute__((pass_object_size(1))), int n) {
+ // CHECK: __ubsan_handle_out_of_bounds
+ // CHECK: ret i32
+ return p[n];
+}
+
+// CHECK-LABEL: define i32 @mat(
+int mat(int *const p __attribute__((pass_object_size(2))), int n) {
+ // CHECK-NOT: __ubsan_handle_out_of_bounds
+ // CHECK: ret i32
+ return p[n];
+}
+
+// CHECK-LABEL: define i32 @pat(
+int pat(int *const p __attribute__((pass_object_size(3))), int n) {
+ // CHECK-NOT: __ubsan_handle_out_of_bounds
+ // CHECK: ret i32
+ return p[n];
+}
+
+// CHECK-LABEL: define i32 @cat(
+int cat(int p[static 10], int n) {
+ // CHECK: icmp ult i64 {{.*}}, 10, !nosanitize
+ // CHECK: __ubsan_handle_out_of_bounds
+ // CHECK: ret i32
+ return p[n];
+}
+
+// CHECK-LABEL: define i32 @bat(
+int bat(int n, int p[n]) {
+ // CHECK-NOT: __ubsan_handle_out_of_bounds
+ // CHECK: ret i32
+ return p[n];
+}