PR tree-optimization/89350 - Wrong -Wstringop-overflow= warning since r261518

gcc/ChangeLog:

	PR tree-optimization/89350
	* builtins.c (compute_objsize): Also ignore offsets whose upper
	bound is negative.
	* gimple-ssa-warn-restrict.c (builtin_memref): Add new member.
	(builtin_memref::builtin_memref): Initialize new member.
	Allow EXPR to be null.
	(builtin_memref::extend_offset_range): Replace local with a member.
	Avoid assuming pointer offsets are unsigned.
	(builtin_memref::set_base_and_offset): Determine base object
	before computing offset range.
	(builtin_access::builtin_access): Handle memset.
	(builtin_access::generic_overlap): Replace local with a member.
	(builtin_access::strcat_overlap): Same.
	(builtin_access::overlap): Same.
	(maybe_diag_overlap): Same.
	(maybe_diag_access_bounds): Same.
	(wrestrict_dom_walker::check_call): Handle memset.
	(check_bounds_or_overlap): Same.

gcc/testsuite/ChangeLog:

	PR tree-optimization/89350
	* gcc.dg/Wstringop-overflow.c: Xfail overly ambitious tests.
	* gcc.dg/Wstringop-overflow-11.c: New test.
	* gcc.dg/Wstringop-overflow-12.c: New test.
	* gcc.dg/pr89350.c: New test.
	* gcc.dg/pr40340-1.c: Adjust expected warning.
	* gcc.dg/pr40340-2.c: Same.
	* gcc.dg/pr40340-4.c: Same.
	* gcc.dg/pr40340-5.c: Same.

From-SVN: r269867

gcc/ChangeLog

+2019-03-21  Martin Sebor  <msebor@redhat.com>
+
+	PR tree-optimization/89350
+	* builtins.c (compute_objsize): Also ignore offsets whose upper
+	bound is negative.
+	* gimple-ssa-warn-restrict.c (builtin_memref): Add new member.
+	(builtin_memref::builtin_memref): Initialize new member.
+	Allow EXPR to be null.
+	(builtin_memref::extend_offset_range): Replace local with a member.
+	Avoid assuming pointer offsets are unsigned.
+	(builtin_memref::set_base_and_offset): Determine base object
+	before computing offset range.
+	(builtin_access::builtin_access): Handle memset.
+	(builtin_access::generic_overlap): Replace local with a member.
+	(builtin_access::strcat_overlap): Same.
+	(builtin_access::overlap): Same.
+	(maybe_diag_overlap): Same.
+	(maybe_diag_access_bounds): Same.
+	(wrestrict_dom_walker::check_call): Handle memset.
+	(check_bounds_or_overlap): Same.
+
 2019-03-21  Jan Hubicka  <hubicka@ucw.cz>
 	    Jakub Jelinek  <jakub@redhat.com>
 

gcc/builtins.c

@@ -3650,7 +3650,8 @@ compute_objsize (tree dest, int ostype)
 		      /* Ignore negative offsets for now.  For others,
 			 use the lower bound as the most optimistic
 			 estimate of the (remaining)size.  */
-		      if (wi::sign_mask (min))
+		      if (wi::sign_mask (min)
+			  || wi::sign_mask (max))
 			;
 		      else if (wi::ltu_p (min, wisiz))
 			return wide_int_to_tree (TREE_TYPE (size),

gcc/testsuite/ChangeLog

+2019-03-21  Martin Sebor  <msebor@redhat.com>
+
+	PR tree-optimization/89350
+	* gcc.dg/Warray-bounds-40.c: Remove an xfail.
+	* gcc.dg/Wstringop-overflow.c: Xfail overly ambitious tests.
+	* gcc.dg/Wstringop-overflow-11.c: New test.
+	* gcc.dg/Wstringop-overflow-12.c: New test.
+	* gcc.dg/pr89350.c: New test.
+	* gcc.dg/pr40340-1.c: Adjust expected warning.
+	* gcc.dg/pr40340-2.c: Same.
+	* gcc.dg/pr40340-4.c: Same.
+	* gcc.dg/pr40340-5.c: Same.
+
 2019-03-21  Jakub Jelinek  <jakub@redhat.com>
 
 	PR lto/89692

gcc/testsuite/gcc.dg/Warray-bounds-40.c

@@ -42,7 +42,7 @@ void test_memmove (void)
 
 void test_memset (void)
 {
-  memset (d, 0, SIZE_MAX - 2);    /* { dg-warning ".memset. pointer overflow between offset 0 and size \[0-9\]+ \\\[-Warray-bounds" "bug" { xfail *-*-* } } */
+  memset (d, 0, SIZE_MAX - 2);    /* { dg-warning ".memset. pointer overflow between offset 0 and size \[0-9\]+ \\\[-Warray-bounds" } */
 }
 
 

gcc/testsuite/gcc.dg/Wstringop-overflow-12.c

+/* PR tree-optimization/89350 - Wrong -Wstringop-overflow warning
+   on a variable offset from the end of an array
+   Test exercising -Wstringop-truncation alone, with -Warray-bounds
+   explicitly disabled.
+   { dg-do compile }
+   { dg-options "-O2 -Wno-array-bounds -Wstringop-overflow -ftrack-macro-expansion=0" }  */
+
+#include "range.h"
+
+extern void* memcpy (void*, const void*, size_t);
+extern void* memset (void*, int, size_t);
+
+void sink (void*);
+
+extern char ga7[7];
+
+
+#define T(d, n) (memcpy ((d), s, (n)), sink (d))
+
+void test_memcpy_array_cst_range_off (const void *s)
+{
+  char *d = ga7 + 1;
+
+  T (d + UR (1, 2), 1);
+  T (d + UR (1, 2), 5);
+
+  T (d + UR (0, 1), 6);
+  T (d + UR (0, 1), 7);       /* { dg-warning ".memcpy. writing 6 bytes into a region of size 5 overflows the destination" "pr89428" { xfail *-*-* } } */
+  T (d + UR (1, 2), 6);       /* { dg-warning ".memcpy. writing 6 bytes into a region of size 5 overflows the destination" } */
+  T (d + UR (1, 2), 7);       /* { dg-warning "writing 7 bytes into a region of size 5 " } */
+
+  T (d + SR (-3, -2), 1);     /* { dg-warning "writing 1 byte into a region of size 0 " "pr85350" { xfail *-*-* } } */
+  T (d + SR (-2, -1), 1);
+  T (d + SR (-2, -1), 2);     /* { dg-warning "writing 2 bytes into a region of size 7 " "pr89428" { xfail *-*-* } } */
+  T (d + SR (-2, -1), 9);     /* { dg-warning "writing 9 bytes into a region of size 7 " "pr85350" { xfail *-*-* } } */
+
+  d = ga7 + 7;
+  T (d + SR (-7, -6), 1);
+  T (d + SR (-7, -1), 1);
+  T (d + SR (-2, -1), 3);     /* { dg-warning "writing 3 bytes into a region of size 2 " "pr85350" { xfail *-*-* } } */
+
+  T (d + UR (1, 2), 1);       /* { dg-warning "writing 1 byte into a region of size 0 " "pr89350" { xfail *-*-* } } */
+}
+
+
+void test_memcpy_array_range_range_off (const void *s)
+{
+  char *d = ga7 + UR (0, 1);
+  T (d + SR (-1, 0), 1);
+  T (d + SR (-1, 0), 7);
+  T (d + SR (-1, 0), 9);       /* { dg-warning "writing 1 byte into a region of size 0 " "pr89350" { xfail *-*-* } } */
+}
+
+
+#undef T
+#define T(d, n) (memset ((d), 0, (n)), sink (d))
+
+void test_memset_array_unsigned_off (void)
+{
+  char *d = ga7 + 1;
+
+  T (d + UR (1, 2), 1);
+  T (d + UR (1, 2), 5);
+
+  T (d + UR (0, 1), 6);
+  T (d + UR (0, 1), 7);       /* { dg-warning ".memset. writing 6 bytes into a region of size 5 overflows the destination" "pr89428" { xfail *-*-* } } */
+  T (d + UR (1, 2), 6);       /* { dg-warning ".memset. writing 6 bytes into a region of size 5 overflows the destination" } */
+  T (d + UR (1, 2), 7);       /* { dg-warning "writing 7 bytes into a region of size 5 " } */
+
+  T (d + SR (-3, -2), 1);     /* { dg-warning "writing 1 byte into a region of size 0 " "pr85350" { xfail *-*-* } } */
+  T (d + SR (-2, -1), 1);
+  T (d + SR (-2, -1), 2);     /* { dg-warning "writing 2 bytes into a region of size 7 " "pr89428" { xfail *-*-* } } */
+  T (d + SR (-2, -1), 9);     /* { dg-warning "writing 9 bytes into a region of size 7 " "pr85350" { xfail *-*-* } } */
+
+  d = ga7 + 7;
+  T (d + SR (-7, -6), 1);
+  T (d + SR (-7, -1), 1);
+  T (d + SR (-2, -1), 3);     /* { dg-warning "writing 3 bytes into a region of size 2 " "pr85350" { xfail *-*-* } } */
+
+  T (d + UR (1, 2), 1);       /* { dg-warning "writing 1 byte into a region of size 0 " } */
+}
+
+
+
+struct MemArray { char a7[7], a3[3], c; };
+
+extern struct MemArray gma;
+
+void test_memset_memarray (void)
+{
+  char *d = gma.a7 + 1;
+
+  T (d + UR (1, 2), 1);
+  T (d + UR (1, 2), 5);
+
+  T (d + UR (0, 1), 6);
+  T (d + UR (0, 1), 7);       /* { dg-warning ".memset. writing 6 bytes into a region of size 5 overflows the destination" "pr89428" { xfail *-*-* } } */
+  T (d + UR (1, 2), 6);       /* { dg-warning ".memset. writing 6 bytes into a region of size 5 overflows the destination" "pr89350" { xfail *-*-* } } */
+  T (d + UR (1, 2), 7);       /* { dg-warning "writing 7 bytes into a region of size 5 " "pr85350" { xfail *-*-* } } */
+
+}
+
+
+#undef T
+#define T(d, n) (memcpy ((d), s, (n)), sink (d))
+
+void test_memcpy_array_signed_off (const void *s)
+{
+  char *d = ga7 + 1;
+
+  T (d + SR (-7, 7), 7);
+  T (d + SR (-1, 1), 7);
+  T (d + SR (-1, 1), 9);      /* { dg-warning "writing 9 bytes into a region of size " "pr89428" { xfail *-*-* } } */
+  T (d + SR (-1, 2), 9);      /* { dg-warning "writing 9 bytes into a region of size " "pr89428" { xfail *-*-* } } */
+  T (d + SR (1, 2), 1);
+  T (d + SR (1, 2), 5);
+
+  T (d + SR (0, 1), 6);
+  T (d + UR (1, 2), 7);       /* { dg-warning "\\\[-Warray-bounds|-Wstringop-overflow" } */
+}

gcc/testsuite/gcc.dg/Wstringop-overflow.c

@@ -51,8 +51,8 @@ void test_memcpy_array (const void *s)
   T (a7 + UR (8, 9), s, 7);   /* { dg-warning "writing 7 bytes into a region of size 0" } */
 
   T (a7 + UR (9, 10), s, 7);  /* { dg-warning "writing 7 bytes into a region of size 0" } */
-  T (a7 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), s, 7);  /* { dg-warning "writing 7 bytes into a region of size 0" } */
-  T (a7 + UR (DIFF_MAX, SIZE_MAX), s, 7);  /* { dg-warning "writing 7 bytes into a region of size 0" } */
+  T (a7 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), s, 7);  /* { dg-warning "writing 7 bytes into a region of size 0" "pr85350" { xfail *-*-* } } */
+  T (a7 + UR (DIFF_MAX, SIZE_MAX), s, 7);  /* { dg-warning "writing 7 bytes into a region of size 0" "pr85350" { xfail *-*-*} } */
 
   /* This is valid.  */
   char *d = a7 + 7;
@@ -102,8 +102,8 @@ void test_strcpy_array (void)
   T (a7 + UR (8, 9), "012345");   /* { dg-warning "writing 7 bytes into a region of size 0" } */
 
   T (a7 + UR (9, 10), "012345");  /* { dg-warning "writing 7 bytes into a region of size 0" } */
-  T (a7 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), "012345");  /* { dg-warning "writing 7 bytes into a region of size 0" } */
-  T (a7 + UR (DIFF_MAX, SIZE_MAX), "012345");  /* { dg-warning "writing 7 bytes into a region of size 0" } */
+  T (a7 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), "012345");  /* { dg-warning "writing 7 bytes into a region of size 0" "pr85350" { xfail *-*-* } } */
+  T (a7 + UR (DIFF_MAX, SIZE_MAX), "012345");  /* { dg-warning "writing 7 bytes into a region of size 0" "pr85350" { xfail *-*-* } } */
 
   char *d = a7 + 7;
 
@@ -127,6 +127,6 @@ void test_strncpy_memarray (struct MemArray *p, const void *s)
   T (p->a9 + UR (9, 10), s, 9);   /* { dg-warning "writing 9 bytes into a region of size 0" } */
   T (p->a9 + UR (10, 11), s, 9);  /* { dg-warning "writing 9 bytes into a region of size 0" } */
 
-  T (p->a9 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), s, 1);  /* { dg-warning "writing 1 byte into a region of size 0" } */
-  T (p->a9 + UR (DIFF_MAX, SIZE_MAX), s, 3);  /* { dg-warning "writing 3 bytes into a region of size 0" } */
+  T (p->a9 + UR (DIFF_MAX, DIFF_MAX + (size_t)1), s, 1);  /* { dg-warning "writing 1 byte into a region of size 0" "pr85350" { xfail *-*-* } } */
+  T (p->a9 + UR (DIFF_MAX, SIZE_MAX), s, 3);  /* { dg-warning "writing 3 bytes into a region of size 0" "pr85350" { xfail *-*-* } } */
 }

gcc/testsuite/gcc.dg/pr40340-1.c

@@ -20,5 +20,5 @@ main (void)
   return 0;
 }
 
-/* { dg-warning "writing" "" { target *-*-* } 10 } */
+/* { dg-warning "\\\[-Warray-bounds|-Wstringop-overflow" "" { target *-*-* } 10 } */
 /* { dg-message "file included" "In file included" { target *-*-* } 0 } */

gcc/testsuite/gcc.dg/pr40340-2.c

@@ -12,5 +12,5 @@ main (void)
   return 0;
 }
 
-/* { dg-warning "writing" "" { target *-*-* } 10 } */
+/* { dg-warning "\\\[-Warray-bounds|-Wstringop-overflow" "" { target *-*-* } 10 } */
 /* { dg-message "file included" "In file included" { target *-*-* } 0 } */

gcc/testsuite/gcc.dg/pr40340-4.c

 /* PR middle-end/40340 */
 /* { dg-do compile } */
-/* { dg-options "-O2 -Wall -Wno-system-headers -g" } */
+/* { dg-options "-O2 -Wall -Wno-array-bounds -Wno-system-headers -g" } */
 
 #define TEST3
 #include "pr40340.h"

gcc/testsuite/gcc.dg/pr40340-5.c

@@ -13,5 +13,5 @@ main (void)
   return 0;
 }
 
-/* { dg-warning "writing" "" { target *-*-* } 10 } */
+/* { dg-warning "\\\[-Warray-bounds|-Wstringop-overflow" "" { target *-*-* } 10 } */
 /* { dg-message "file included" "In file included" { target *-*-* } 0 } */

gcc/testsuite/gcc.dg/pr89350.c

+/* PR tree-optimization/89350 - Wrong -Wstringop-overflow warning
+   on a variable offset from the end of an array
+   { dg-do compile }
+   { dg-options "-O2 -Wall" } */
+
+char buf[128];
+char *src = "HCSparta";
+
+int main(int argc, char **argv)
+{
+    char *dst = buf + sizeof(buf);
+
+    if (argc)
+    {
+      dst -= argc;
+      __builtin_memcpy(dst, src, argc + 0);   /* { dg-bogus "\\\[-Warray-bounds|-Wstringop-overflow" } */
+    }
+}