1 files changed, 236 insertions, 0 deletions
diff --git a/test/Analysis/padding_c.c b/test/Analysis/padding_c.c
new file mode 100644
index 000000000000..93cefcad8930
--- /dev/null
+++ b/test/Analysis/padding_c.c
@@ -0,0 +1,236 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=optin.performance -analyzer-config optin.performance.Padding:AllowedPad=2 -verify %s
+
+#if __has_include(<stdalign.h>)
+#include <stdalign.h>
+#endif
+
+#if __has_include(<stdalign.h>) || defined(__cplusplus)
+// expected-warning@+1{{Excessive padding in 'struct FieldAttrAlign' (6 padding}}
+struct FieldAttrAlign {
+  char c1;
+  alignas(4) int i;
+  char c2;
+};
+
+// expected-warning@+1{{Excessive padding in 'struct FieldAttrOverAlign' (10 padding}}
+struct FieldAttrOverAlign {
+  char c1;
+  alignas(8) int i;
+  char c2;
+};
+
+#endif // __has_include(<stdalign.h>) || defined(__cplusplus)
+
+// Re-ordering members of these structs won't reduce padding, so don't warn
+struct LeadingChar { // no-warning
+  char c;
+  int i;
+};
+
+struct TrailingChar { // no-warning
+  int i;
+  char c;
+};
+
+struct Helpless { // no-warning
+  struct TrailingChar i1;
+  struct LeadingChar i2;
+  char c;
+};
+
+#pragma pack(push)
+#pragma pack(1)
+struct SquishedIntSandwich { // no-warning
+  char c1;
+  int i;
+  char c2;
+};
+#pragma pack(pop)
+
+// Re-ordering members of these structs will reduce padding, so warn
+struct IntSandwich { // expected-warning{{Excessive padding in 'struct IntSandwich'}}
+  char c1;
+  int i;
+  char c2;
+};
+
+struct TurDuckHen { // expected-warning{{Excessive padding in 'struct TurDuckHen'}}
+  char c1;
+  struct IntSandwich i;
+  char c2;
+};
+
+#pragma pack(push)
+#pragma pack(2)
+struct SmallIntSandwich { // expected-warning{{Excessive padding in 'struct SmallIntSandwich'}}
+  char c1;
+  int i1;
+  char c2;
+  int i2;
+  char c3;
+  int i3;
+  char c4;
+};
+#pragma pack(pop)
+
+union SomeUnion { // no-warning
+  char c;
+  short s;
+  int i;
+};
+
+struct HoldsAUnion { // expected-warning{{Excessive padding in 'struct HoldsAUnion'}}
+  char c1;
+  union SomeUnion u;
+  char c2;
+};
+
+struct BigCharArray { // no-warning
+  char c[129];
+};
+
+struct SmallCharArray { // no-warning
+  char c[5];
+};
+
+struct MediumIntArray { // no-warning
+  int i[5];
+};
+
+struct LargeSizeToSmallSize { // expected-warning{{Excessive padding in 'struct LargeSizeToSmallSize'}}
+  struct BigCharArray b;
+  struct MediumIntArray m;
+  struct SmallCharArray s;
+};
+
+struct LargeAlignToSmallAlign { // no-warning
+  struct MediumIntArray m;
+  struct BigCharArray b;
+  struct SmallCharArray s;
+};
+
+// Currently ignoring VLA padding problems.  Still need to make sure we don't
+// choke on VLAs though
+struct HoldsVLA { // no-warning
+  char c1;
+  int x;
+  char c2;
+  int vla[];
+};
+
+// Currently ignoring bitfield padding problems.  Still need to make sure we
+// don't choke on bitfields though
+struct HoldsBitfield { // no-warning
+  char c1;
+  int x;
+  char c2;
+  unsigned char b1 : 3;
+  unsigned char b2 : 3;
+  unsigned char b3 : 2;
+};
+
+typedef struct { // expected-warning{{Excessive padding in 'TypedefSandwich'}}
+  char c1;
+  int i;
+  char c2;
+} TypedefSandwich;
+
+// expected-warning@+1{{Excessive padding in 'struct StructAttrAlign' (10 padding}}
+struct StructAttrAlign {
+  char c1;
+  int i;
+  char c2;
+} __attribute__((aligned(8)));
+
+struct CorrectOverlyAlignedChar { // no-warning
+  char c __attribute__((aligned(4096)));
+  char c1;
+  int x1;
+  char c2;
+  int x2;
+  char c3;
+};
+
+struct OverlyAlignedChar { // expected-warning{{Excessive padding in 'struct OverlyAlignedChar'}}
+  char c1;
+  int x;
+  char c2;
+  char c __attribute__((aligned(4096)));
+};
+
+struct HoldsOverlyAlignedChar { // expected-warning{{Excessive padding in 'struct HoldsOverlyAlignedChar'}}
+  char c1;
+  struct OverlyAlignedChar o;
+  char c2;
+};
+
+void internalStructFunc() {
+  struct X { // expected-warning{{Excessive padding in 'struct X'}}
+    char c1;
+    int t;
+    char c2;
+  };
+  struct X obj;
+}
+
+void typedefStructFunc() {
+  typedef struct { // expected-warning{{Excessive padding in 'S'}}
+    char c1;
+    int t;
+    char c2;
+  } S;
+  S obj;
+}
+
+void anonStructFunc() {
+  struct { // expected-warning{{Excessive padding in 'struct (anonymous}}
+    char c1;
+    int t;
+    char c2;
+  } obj;
+}
+
+struct CorrectDefaultAttrAlign { // no-warning
+  long long i;
+  char c1;
+  char c2;
+} __attribute__((aligned));
+
+struct TooSmallShortSandwich { // no-warning
+  char c1;
+  short s;
+  char c2;
+};
+
+// expected-warning@+1{{Excessive padding in 'struct SmallArrayShortSandwich'}}
+struct SmallArrayShortSandwich {
+  char c1;
+  short s;
+  char c2;
+} ShortArray[20];
+
+// expected-warning@+1{{Excessive padding in 'struct SmallArrayInFunc'}}
+struct SmallArrayInFunc {
+  char c1;
+  short s;
+  char c2;
+};
+
+void arrayHolder() {
+  struct SmallArrayInFunc Arr[15];
+}
+
+// xxxexpected-warning@+1{{Excessive padding in 'struct SmallArrayInStruct'}}
+struct SmallArrayInStruct {
+  char c1;
+  short s;
+  char c2;
+};
+
+struct HoldsSmallArray {
+  struct SmallArrayInStruct Field[20];
+} HoldsSmallArrayElt;
+
+void nestedPadding() {
+  struct HoldsSmallArray Arr[15];
+}