PR tree-optimization/91183 - strlen of a strcpy result with a conditional source not folded
PR tree-optimization/86688 - missing -Wstringop-overflow using a non-string local array in strnlen with excessive bound
gcc/ChangeLog:
PR tree-optimization/91183
PR tree-optimization/86688
* builtins.c (compute_objsize): Handle MEM_REF.
* tree-ssa-strlen.c (class ssa_name_limit_t): New.
(get_min_string_length): Remove.
(count_nonzero_bytes): New function.
(handle_char_store): Rename...
(handle_store): to this. Handle multibyte stores via integer types.
(strlen_check_and_optimize_stmt): Adjust conditional and the called
function name.
gcc/testsuite/ChangeLog:
PR tree-optimization/91183
PR tree-optimization/86688
* gcc.dg/Wstringop-overflow-14.c: New test.
* gcc.dg/attr-nonstring-2.c: Remove xfails.
* gcc.dg/strlenopt-70.c: New test.
* gcc.dg/strlenopt-71.c: New test.
* gcc.dg/strlenopt-72.c: New test.
* gcc.dg/strlenopt-8.c: Remove xfails.
From-SVN: r273783
* config/msp430/msp430.h (ENDFILE_SPEC): Wrap uses of crtn*.o in
if-exists.
+2019-07-24 Martin Sebor <msebor@redhat.com>
+
+ PR tree-optimization/91183
+ PR tree-optimization/86688
+ * builtins.c (compute_objsize): Handle MEM_REF.
+ * tree-ssa-strlen.c (class ssa_name_limit_t): New.
+ (get_min_string_length): Remove.
+ (count_nonzero_bytes): New function.
+ (handle_char_store): Rename...
+ (handle_store): to this. Handle multibyte stores via integer types.
+ (strlen_check_and_optimize_stmt): Adjust conditional and the called
+ function name.
+
2019-07-24 Martin Sebor <msebor@redhat.com>
PR driver/80545
if (!ostype)
return NULL_TREE;
+ if (TREE_CODE (dest) == MEM_REF)
+ {
+ tree ref = TREE_OPERAND (dest, 0);
+ tree off = TREE_OPERAND (dest, 1);
+ if (tree size = compute_objsize (ref, ostype))
+ {
+ if (tree_int_cst_lt (off, size))
+ return fold_build2 (MINUS_EXPR, size_type_node, size, off);
+ return integer_zero_node;
+ }
+
+ return NULL_TREE;
+ }
+
if (TREE_CODE (dest) != ADDR_EXPR)
return NULL_TREE;
+2019-07-24 Martin Sebor <msebor@redhat.com>
+
+ PR tree-optimization/91183
+ PR tree-optimization/86688
+ * gcc/testsuite/c-c++-common/ubsan/object-size-9.c: Disable warnings.
+ * gcc.dg/Wstringop-overflow-14.c: New test.
+ * gcc.dg/attr-nonstring-2.c: Remove xfails.
+ * gcc.dg/strlenopt-70.c: New test.
+ * gcc.dg/strlenopt-71.c: New test.
+ * gcc.dg/strlenopt-72.c: New test.
+ * gcc.dg/strlenopt-8.c: Remove xfails.
+
2019-07-24 Martin Sebor <msebor@redhat.com>
PR driver/80545
/* { dg-do run } */
/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
-/* { dg-options "-fsanitize=undefined" } */
+/* { dg-options "-Wno-stringop-overflow -fsanitize=undefined" } */
/* Test PARM_DECLs and RESULT_DECLs. */
--- /dev/null
+/* Test to verify that past-the-end multibyte writes via lvalues of wider
+ types than char are diagnosed.
+ { dg-do compile }
+ { dg-require-effective-target int32plus }
+ { dg-options "-O2 -Wall" } */
+
+typedef __INT16_TYPE__ int16_t;
+typedef __INT32_TYPE__ int32_t;
+typedef __INT64_TYPE__ int64_t;
+typedef __SIZE_TYPE__ size_t;
+
+void* memcpy (void*, const void*, size_t);
+char* strcpy (char*, const char*);
+
+char a4[4], a8[8], a16[16];
+
+const char s4[] = "1234";
+const char t4[] = "4321";
+
+void test_memcpy_cond (int i)
+{
+ char *p = a4 + 1;
+ const char *q = i ? s4 : t4;
+ memcpy (p, q, 4); // { dg-warning "writing 4 bytes into a region of size 3" }
+}
+
+
+void test_int16 (void)
+{
+ char *p = a4 + 1;
+ *(int16_t*)p = 0;
+ *(int16_t*)(p + 2) = 0; // { dg-warning "writing 2 bytes into a region of size 1" }
+}
+
+
+void test_int32 (void)
+{
+ char *p = a8 + 3;
+ *(int32_t*)p = 0;
+ *(int32_t*)(p + 2) = 0; // { dg-warning "writing 4 bytes into a region of size 3" }
+}
+
+
+void test_int64 (void)
+{
+ char *p = a16 + 5;
+ *(int64_t*)p = 0;
+ *(int64_t*)(p + 5) = 0; // { dg-warning "writing 8 bytes into a region of size 6" }
+}
T (3, "12", 3, 1);
T (3, "12", 3, 9);
T (3, "123", 3, 1);
- T (3, "123", 3, 4); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound 4" "bug 86688" { xfail *-*-* } } */
- T (3, "123", 3, 9); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound 9" "bug 86688" { xfail *-*-* } } */
+ T (3, "123", 3, 4); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound 4" } */
+ T (3, "123", 3, 9); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound 9" } */
T (5, "1", 2, 1);
T (5, "1", 2, 2);
{
T (3, "1", 2, UR (0, 1));
T (3, "1", 2, UR (3, 9));
- T (3, "123", 3, UR (4, 5)); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound \\\[4, 5]" "bug 86688" { xfail *-*-* } } */
- T (3, "123", 3, UR (5, 9)); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound \\\[5, 9]" "bug 86688" { xfail *-*-* } } */
+ T (3, "123", 3, UR (4, 5)); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound \\\[4, 5]" } */
+ T (3, "123", 3, UR (5, 9)); /* { dg-warning "argument 1 declared attribute .nonstring. is smaller than the specified bound \\\[5, 9]" } */
}
--- /dev/null
+/* PR tree-optimization/91183 - strlen of a strcpy result with a conditional
+ source not folded
+ Test to verify that strlen can determine string lengths from wider stores
+ than narrow characters. This matters because on targets that can handle
+ unaligned stores and where GCC lowers multi-character stores into smaller
+ numbers of wider stores.
+ { dg-do compile }
+ { dg-options "-O2 -fdump-tree-optimized" } */
+
+#include "strlenopt.h"
+
+#define CHAR_BIT __CHAR_BIT__
+
+typedef __INT16_TYPE__ int16_t;
+typedef __INT32_TYPE__ int32_t;
+typedef __INT64_TYPE__ int64_t;
+typedef __UINT64_TYPE__ uint64_t;
+
+#define CAT(x, y) x ## y
+#define CONCAT(x, y) CAT (x, y)
+#define FAILNAME(name) CONCAT (call_ ## name ##_on_line_, __LINE__)
+
+#define FAIL(name) do { \
+ extern void FAILNAME (name) (void); \
+ FAILNAME (name)(); \
+ } while (0)
+
+/* Macros to emit a call to function named
+ call_failed_to_be_eliminated_on_line_NNN()
+ for each call that's expected to be eliminated. The dg-final
+ scan-tree-dump-time directive at the bottom of the test verifies
+ that no such call appears in output. */
+#define ELIM(expr) \
+ if ((expr)) FAIL (not_eliminated); else (void)0
+
+/* Verify that 'strlen (A) EXPECT' is folded to true. When non-null,
+ the first sizeof (INIT) - 1 bytes of the INIT arrray are stored
+ in A first, followed by *(TYPE*)A = ASSIGN. */
+#define T(init, type, off, assign, expect) do { \
+ char a[32]; \
+ memcpy (a, init ? init : "", init ? sizeof init - 1 : 0); \
+ *(type*)(a + off) = assign; \
+ ELIM (!(strlen (a) expect)); \
+ } while (0)
+
+/* Same as above but the assignment consisting of the two quadwords
+ QW1 and QW2 to support int128_t. */
+#define T2(init, type, off, qw0, qw1, expect) do { \
+ char a[32]; \
+ memcpy (a, init ? init : "", init ? sizeof init - 1: 0); \
+ type assign = ((type)qw0 << (sizeof (type) * CHAR_BIT / 2)) | (type)qw1; \
+ *(type*)(a + off) = assign; \
+ ELIM (!(strlen (a) expect)); \
+ } while (0)
+
+/* Same as T but works around the optimizer dropping the initializing
+ store before the assignment and defeating the strlen optimization. */
+#define TX(init, type, off, assign, expect) do { \
+ char a[32]; \
+ strcpy (a, init + 2); \
+ strcat (a, init + sizeof (init) - 3); \
+ *(type*)(a + off) = assign; \
+ ELIM (!(strlen (a) expect)); \
+ } while (0)
+
+
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define I16(s) ((s[0] << 8) + s[1])
+# define I32(s) ((s[0] << 24) + (s[1] << 16) + (s[2] << 8) + s[3])
+# define I64(s) \
+ (((uint64_t)s[0] << 56) \
+ + ((uint64_t)s[1] << 48) \
+ + ((uint64_t)s[2] << 40) \
+ + ((uint64_t)s[3] << 32) \
+ + ((uint64_t)s[4] << 24) \
+ + ((uint64_t)s[5] << 16) \
+ + ((uint64_t)s[6] << 8) \
+ + s[7])
+#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+# define I16(s) ((s[1] << 8) + s[0])
+# define I32(s) ((s[3] << 24) + (s[2] << 16) + (s[1] << 8) + s[0])
+# define I64(s) \
+ (((uint64_t)s[7] << 56) \
+ + ((uint64_t)s[6] << 48) \
+ + ((uint64_t)s[5] << 40) \
+ + ((uint64_t)s[4] << 32) \
+ + ((uint64_t)s[3] << 24) \
+ + ((uint64_t)s[2] << 16) \
+ + ((uint64_t)s[1] << 8) \
+ + s[0])
+#endif
+
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+
+void store_16bit_be (void)
+{
+ T ("xxx", int16_t, 0, 0x0001, == 0);
+ T ("xxx", int16_t, 0, 0x0010, == 0);
+ T ("xxx", int16_t, 0, 0x0011, == 0);
+ T ("xxx", int16_t, 0, 0x0100, == 1);
+ T ("xxx", int16_t, 0, 0x1000, == 1);
+ T ("xxx", int16_t, 0, 0x1100, == 1);
+}
+
+#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+
+void store_16bit_le (int i)
+{
+ int16_t x0000 = I16 ("\0\0");
+ int16_t x0001 = 0x0001;
+ int16_t x0010 = 0x0010;
+ int16_t x0011 = 0x0011;
+ int16_t x0100 = 0x0100;
+ int16_t x1000 = 0x1000;
+ int16_t x1100 = 0x1100;
+
+ T (0, int16_t, 0, x0000, == 0);
+ T ("x", int16_t, 0, x0000, == 0);
+ T ("xx", int16_t, 0, x0000, == 0);
+ T ("xxxx", int16_t, 0, x0000, == 0);
+ T (0, int16_t, 0, x0001, == 1);
+ T ("\0\0\0", int16_t, 0, x0001, == 1);
+ T (0, int16_t, 0, x0010, == 1);
+ T ("x\0\0", int16_t, 0, x0010, == 1);
+ T (0, int16_t, 0, x0011, == 1);
+ T ("xx\0", int16_t, 0, x0011, == 1);
+ T (0, int16_t, 0, x0100, == 0);
+ T ("\0\0\0", int16_t, 0, x0100, == 0);
+ T (0, int16_t, 0, x1000, == 0);
+ T ("x\0\0", int16_t, 0, x1000, == 0);
+ T (0, int16_t, 0, x1100, == 0);
+ T ("xx\0", int16_t, 0, x1100, == 0);
+
+ // FIXME: This fails because of the next test but succeeds on its own.
+ // T (0, int16_t, 0, i ? x0001 : x0010, == 1);
+ T ("xxx", int16_t, 0, i ? x0100 : x1100, == 0);
+}
+
+#endif
+
+void store_32bit (volatile int i)
+{
+ T (0, int32_t, 0, 0, == 0);
+ T ("x", int32_t, 0, 0, == 0);
+ T ("xx", int32_t, 0, 0, == 0);
+ T ("xxx", int32_t, 0, 0, == 0);
+ T ("xxxx", int32_t, 0, 0, == 0);
+
+ T ("\0", int32_t, 1, 0, == 0);
+ T ("x", int32_t, 1, 0, == 1);
+ T ("xx", int32_t, 2, 0, == 2);
+ T ("xxx", int32_t, 3, 0, == 3);
+
+ T ("xxx", int32_t, 0, I32 ("\01\0\0\0"), == 1);
+ T ("xxx", int32_t, 0, I32 ("\0\01\0\0"), == 0);
+ T ("xxx", int32_t, 0, I32 ("\0\0\01\0"), == 0);
+ T ("xxx", int32_t, 0, I32 ("\0\0\0\01"), == 0);
+
+ T ("xxx", int32_t, 0, I32 ("\1\2\0\0"), == 2);
+ T ("xxx", int32_t, 0, I32 ("\0\1\2\0"), == 0);
+ T ("xxx", int32_t, 0, I32 ("\0\0\1\2"), == 0);
+
+ T ("xxx", int32_t, 0, I32 ("\1\2\3\0"), == 3);
+ T ("xxx", int32_t, 0, I32 ("\0\1\2\3"), == 0);
+
+ int32_t x00332211 = I32 ("123\0");
+ int32_t x00002211 = I32 ("12\0\0");
+ int32_t x00000011 = I32 ("1\0\0\0");
+
+ T ("xxxx", int32_t, 0, i ? x00332211 : x00002211, <= 3);
+ T ("xxxx", int32_t, 0, i ? x00332211 : x00002211, >= 2);
+ T ("xxxx", int32_t, 0, i ? x00332211 : x00000011, <= 3);
+ T ("xxxx", int32_t, 0, i ? x00332211 : x00000011, >= 1);
+
+ TX ("abcde", int32_t, 0, i ? I32 ("1234") : I32 ("1235"), == 5);
+ TX ("abcde", int32_t, 1, i ? I32 ("1234") : I32 ("1235"), == 5);
+
+ TX ("abcdef", int32_t, 0, i ? I32 ("1235") : I32 ("1234"), == 6);
+ TX ("abcdef", int32_t, 1, i ? I32 ("1235") : I32 ("1234"), == 6);
+ TX ("abcdef", int32_t, 2, i ? I32 ("1235") : I32 ("1234"), == 6);
+ TX ("abcdef", int32_t, 3, i ? I32 ("124\0") : I32 ("123\0"), == 6);
+ TX ("abcdef", int32_t, 3, i ? I32 ("12\0\0") : I32 ("13\0\0"), == 5);
+
+ TX ("abcdef", int32_t, 3, i ? I32 ("12\0\0") : I32 ("123\0"), >= 5);
+ TX ("abcdef", int32_t, 3, i ? I32 ("12\0\0") : I32 ("123\0"), < 7);
+}
+
+void store_64bit (int i)
+{
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\1\0\0\0"), == 1);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\1\0\0"), == 0);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\0\1\0"), == 0);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\00\0\1"), == 0);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\1\0\0\0"), 0, == 0);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\0\1\0\0"), 0, == 0);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\0\0\1\0"), 0, == 0);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\0\0\0\1"), 0, == 0);
+
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\1\2\0\0"), == 2);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\1\2\0"), == 0);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\0\1\2"), == 0);
+
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\1\2\3\0"), == 3);
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\0\1\2\3"), == 0);
+
+ T2 ("xxxxxxx", int64_t, 0, 0, I32 ("\1\2\3\4"), == 4);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\5\0\0\0"), I32 ("\1\2\3\4"), == 5);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\5\6\0\0"), I32 ("\1\2\3\4"), == 6);
+ T2 ("xxxxxxx", int64_t, 0, I32 ("\5\6\7\0"), I32 ("\1\2\3\4"), == 7);
+
+ int64_t x7777777 = I64 ("\7\7\7\7\7\7\7");
+ int64_t x666666 = I64 ("\6\6\6\6\6\6\0");
+ int64_t x4444 = I64 ("\4\4\4\4\0\0\0");
+ int64_t x3333 = I64 ("\3\3\3\3\0\0\0");
+ int64_t x1 = I64 ("\1\0\0\0\0\0\0");
+
+ T ("x\0xxxxxx", int64_t, 0, i ? x7777777 : x666666, <= 7);
+ T ("xx\0xxxxx", int64_t, 0, i ? x7777777 : x666666, >= 6);
+ T ("xxx\0xxxx", int64_t, 0, i ? x666666 : x1, <= 6);
+ T ("xxxx\0xxx", int64_t, 0, i ? x666666 : x1, >= 1);
+ T ("xxxxxx\0x", int64_t, 0, i ? x4444 : x3333, == 4);
+}
+
+#ifdef __uint128_t
+
+typedef __uint128_t uint128_t;
+
+void store_128bit (void)
+{
+ uint64_t x1 = I64 ("\1\0\0\0\0\0\0\0");
+ uint64_t x01 = I64 ("\0\1\0\0\0\0\0\0");
+ uint64_t x001 = I64 ("\0\0\1\0\0\0\0\0");
+ uint64_t x0001 = I64 ("\0\0\0\1\0\0\0\0");
+ uint64_t x00001 = I64 ("\0\0\0\0\1\0\0\0");
+ uint64_t x000001 = I64 ("\0\0\0\0\0\1\0\0");
+ uint64_t x0000001 = I64 ("\0\0\0\0\0\0\1\0");
+ uint64_t x00000001 = I64 ("\0\0\0\0\0\0\0\1");
+
+ T2 ("xxxxxxx", uint128_t, 0, 0, x1, == 1);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x01, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x001, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x0001, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x00001, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x000001, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x0000001, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, 0, x00000001, == 0);
+
+ T2 ("xxxxxxx", uint128_t, 0, x1, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x01, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x001, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x0001, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x00001, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x000001, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x0000001, 0, == 0);
+ T2 ("xxxxxxx", uint128_t, 0, x00000001, 0, == 0);
+
+ T2 ("xxxxxxx", uint128_t, 0, 0, I64 ("\2\1\0\0\0\0\0\0"), == 2);
+ T2 ("xxxxxxx", uint128_t, 0, 0, I64 ("\0\2\1\0\0\0\0\0"), == 0);
+
+ T2 ("xxxxxxx", uint128_t, 0, 0, I64 ("\3\2\1\0\0\0\0\0"), == 3);
+ T2 ("xxxxxxx", uint128_t, 0, 0, I64 ("\0\3\2\1\0\0\0\0"), == 0);
+
+ uint64_t x4321 = I64 ("\4\3\2\1\0\0\0\0");
+ uint64_t x54321 = I64 ("\5\4\3\2\1\0\0\0");
+ uint64_t x654321 = I64 ("\6\5\4\3\2\1\0\0");
+ uint64_t x7654321 = I64 ("\7\6\5\4\3\2\1\0");
+ uint64_t x87654321 = I64 ("8\7\6\5\4\3\2\1");
+ uint64_t x9 = I64 ("9\0\0\0\0\0\0\0");
+ uint64_t xa9 = I64 ("a9\0\0\0\0\0\0");
+ uint64_t xba9 = I64 ("ba9\0\0\0\0\0\0");
+ uint64_t xcba9 = I64 ("cba9\0\0\0\0\0");
+ uint64_t xdcba9 = I64 ("dcba9\0\0\0\0");
+ uint64_t xedcba9 = I64 ("edcba9\0\0\0\0");
+ uint64_t xfedcba9 = I64 ("fedcba9\0\0\0");
+
+ T2 (0, uint128_t, 0, 0, x4321, == 4);
+ T2 (0, uint128_t, 0, 0, x54321, == 5);
+ T2 (0, uint128_t, 0, 0, x654321, == 6);
+ T2 (0, uint128_t, 0, 0, x7654321, == 7);
+ T2 (0, uint128_t, 0, 0, x87654321, == 8);
+ T2 (0, uint128_t, 0, x9, x87654321, == 9);
+ T2 (0, uint128_t, 0, xa9, x87654321, == 10);
+ T2 (0, uint128_t, 0, xba9, x87654321, == 11);
+ T2 (0, uint128_t, 0, xcba9, x87654321, == 12);
+ T2 (0, uint128_t, 0, xdcba9, x87654321, == 13);
+ T2 (0, uint128_t, 0, xedcba9, x87654321, == 14);
+ T2 (0, uint128_t, 0, xfedcba9, x87654321, == 15);
+}
+
+#endif // __uint128_t
+
+/* { dg-final { scan-tree-dump-times "strlen" 0 "optimized" } }
+ { dg-final { scan-tree-dump-times "_not_eliminated_" 0 "optimized" } } */
--- /dev/null
+/* PR tree-optimization/91183 - strlen of a strcpy result with a conditional
+ source not folded
+ Runtime test to verify that multibyte stores are handled correctly.
+ { dg-do run }
+ { dg-options "-O2 -Wall" } */
+
+#include "strlenopt.h"
+
+#define CHAR_BIT __CHAR_BIT__
+
+typedef __INT16_TYPE__ int16_t;
+typedef __INT32_TYPE__ int32_t;
+
+#define NOIPA __attribute__ ((noclone, noinline, noipa))
+
+/* Prevent the optimizer from detemining invariants from prior tests. */
+NOIPA void terminate (void)
+{
+ __builtin_abort ();
+}
+
+#define VERIFY(expr, str) \
+ do { \
+ const unsigned expect = strlen (str); \
+ const unsigned len = strlen (expr); \
+ if (len != expect) \
+ { \
+ __builtin_printf ("line %i: strlen(%s) == %u failed: " \
+ "got %u with a = \"%.*s\"\n", \
+ __LINE__, #expr, expect, len, \
+ (int)sizeof a, a); \
+ terminate (); \
+ } \
+ if (memcmp (a, str, expect + 1)) \
+ { \
+ __builtin_printf ("line %i: expected string \"%s\", " \
+ "got a = \"%.*s\"\n", \
+ __LINE__, str, (int)sizeof a, a); \
+ terminate (); \
+ } \
+ } while (0)
+
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define I16(s) ((s[0] << 8) + s[1])
+# define I32(s) ((s[0] << 24) + (s[1] << 16) + (s[2] << 8) + s[3])
+#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+# define I16(s) ((s[1] << 8) + s[0])
+# define I32(s) ((s[3] << 24) + (s[2] << 16) + (s[1] << 8) + s[0])
+#endif
+
+char a[32];
+
+NOIPA void
+i16_1 (void)
+{
+ *(int16_t*)a = I16 ("12");
+ *(int16_t*)(a + 2) = I16 ("3");
+ VERIFY (a, "123");
+
+ *(int16_t*)(a + 1) = I16 ("23");
+ VERIFY (a, "123");
+
+ *(int16_t*)(a) = I16 ("12");
+ VERIFY (a, "123");
+
+ *(int16_t*)(a + 1) = I16 ("2");
+ VERIFY (a, "12");
+
+ *(int16_t*)(a + 3) = I16 ("45");
+ *(int16_t*)(a + 2) = I16 ("34");
+ VERIFY (a, "12345");
+}
+
+NOIPA void
+i16_2 (void)
+{
+ strcpy (a, "12");
+ strcat (a, "34");
+
+ *(int16_t*)a = I16 ("12");
+ VERIFY (a, "1234");
+
+ *(int16_t*)(a + 1) = I16 ("12");
+ VERIFY (a, "1124");
+
+ *(int16_t*)(a + 2) = I16 ("12");
+ VERIFY (a, "1112");
+
+ *(int16_t*)(a + 3) = I16 ("12");
+ VERIFY (a, "11112");
+
+ *(int16_t*)(a + 4) = I16 ("12");
+ VERIFY (a, "111112");
+}
+
+
+NOIPA void
+i32_1 (void)
+{
+ *(int32_t*)a = I32 ("1234");
+ VERIFY (a, "1234");
+
+ *(int32_t*)(a + 1) = I32 ("2345");
+ VERIFY (a, "12345");
+}
+
+NOIPA void
+i32_2 (void)
+{
+ strcpy (a, "12");
+ strcat (a, "34");
+
+ *(int32_t*)a = I32 ("1234");
+ VERIFY (a, "1234");
+
+ *(int32_t*)(a + 4) = I32 ("567");
+ VERIFY (a, "1234567");
+
+ *(int32_t*)(a + 7) = I32 ("89\0");
+ VERIFY (a, "123456789");
+
+ *(int32_t*)(a + 3) = I32 ("4567");
+ VERIFY (a, "123456789");
+
+ *(int32_t*)(a + 2) = I32 ("3456");
+ VERIFY (a, "123456789");
+
+ *(int32_t*)(a + 1) = I32 ("2345");
+ VERIFY (a, "123456789");
+}
+
+
+NOIPA void
+i32_3 (void)
+{
+ strcpy (a, "1234");
+ strcat (a, "5678");
+
+ *(int32_t*)a = I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)(a + 1) = I32 ("234");
+ VERIFY (a, "1234");
+
+ *(int32_t*)(a + 2) = I32 ("3456");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)(a + 3) = I32 ("4567");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)(a + 4) = I32 ("5678");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)(a + 5) = I32 ("6789");
+ VERIFY (a, "123456789");
+
+ *(int32_t*)(a + 6) = I32 ("789A");
+ VERIFY (a, "123456789A");
+}
+
+volatile int vzero = 0;
+
+NOIPA void
+i32_4 (void)
+{
+ strcpy (a, "1234");
+ strcat (a, "5678");
+
+ *(int32_t*)a = vzero ? I32 ("1\0\0\0") : I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)a = vzero ? I32 ("12\0\0") : I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)a = vzero ? I32 ("123\0") : I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)a = vzero ? I32 ("1234") : I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)a = vzero ? I32 ("1235") : I32 ("1234");
+ VERIFY (a, "12345678");
+
+ *(int32_t*)a = vzero ? I32 ("1234") : I32 ("123\0");
+ VERIFY (a, "123");
+
+ *(int32_t*)(a + 3) = vzero ? I32 ("456\0") : I32 ("4567");
+ VERIFY (a, "12345678");
+}
+
+
+int main ()
+{
+ memset (a, 0, sizeof a);
+ i16_1 ();
+
+ memset (a, 0, sizeof a);
+ i16_2 ();
+
+
+ memset (a, 0, sizeof a);
+ i32_1 ();
+
+ memset (a, 0, sizeof a);
+ i32_2 ();
+
+ memset (a, 0, sizeof a);
+ i32_3 ();
+
+ memset (a, 0, sizeof a);
+ i32_4 ();
+}
--- /dev/null
+/* PR tree-optimization/91183 - strlen of a strcpy result with a conditional
+ source not folded
+ Test to verify that strlen can determine string lengths from wider stores
+ than narrow characters. This matters because on targets that can handle
+ unaligned stores and where GCC lowers multi-character stores into smaller
+ numbers of wider stores.
+ { dg-do compile }
+ { dg-options "-O2 -fdump-tree-optimized" } */
+
+#include "strlenopt.h"
+
+#define CAT(x, y) x ## y
+#define CONCAT(x, y) CAT (x, y)
+#define FAILNAME(name) CONCAT (call_ ## name ##_on_line_, __LINE__)
+
+#define FAIL(name) do { \
+ extern void FAILNAME (name) (void); \
+ FAILNAME (name)(); \
+ } while (0)
+
+/* Macros to emit a call to function named
+ call_failed_to_be_eliminated_on_line_NNN()
+ for each call that's expected to be eliminated. The dg-final
+ scan-tree-dump-time directive at the bottom of the test verifies
+ that no such call appears in output. */
+#define ELIM(expr) \
+ if ((expr)) FAIL (not_eliminated); else (void)0
+
+#undef T
+#define T(N, ncpy, expect, assign) do { \
+ char a[N], b[N]; \
+ assign; \
+ memcpy (b, a, ncpy); \
+ ELIM (!(expect == strlen (b))); \
+ } while (0)
+
+void test_copy (void)
+{
+ T (2, 1, 0, (a[0] = 0));
+ T (2, 2, 0, (a[0] = 0, a[1] = 0));
+ T (2, 2, 1, (a[0] = '1', a[1] = 0));
+ T (4, 3, 2, (a[0] = '1', a[1] = '2', a[2] = 0));
+ // Not handled due to pr83821:
+ // T (4, 3, 1, (a[0] = '1', a[1] = 0, a[2] = '2'));
+ T (4, 2, 1, (a[0] = '1', a[1] = 0, a[2] = 0, a[3] = 0));
+ // Not handled due to pr83821:
+ // T (4, 3, 1, (a[0] = '1', a[1] = 0, a[2] = 0, a[3] = 0));
+ T (4, 4, 1, (a[0] = '1', a[1] = 0, a[2] = 0, a[3] = 0));
+ T (4, 3, 2, (a[0] = '1', a[1] = '2', a[2] = 0, a[3] = 0));
+ T (4, 4, 2, (a[0] = '1', a[1] = '2', a[2] = 0, a[3] = 0));
+ T (4, 4, 3, (a[0] = '1', a[1] = '2', a[2] = '3', a[3] = 0));
+ T (5, 4, 1, (a[0] = '1', a[1] = 0, a[2] = 0, a[3] = 0));
+ T (5, 4, 2, (a[0] = '1', a[1] = '2', a[2] = 0, a[3] = 0));
+ T (5, 4, 3, (a[0] = '1', a[1] = '2', a[2] = '3', a[3] = 0));
+ // Not handled:
+ // T (5, 5, 1, (a[0] = '1', a[1] = 0, a[2] = 0, a[3] = 0, a[4] = 0));
+ // T (5, 5, 2, (a[0] = '1', a[1] = '2', a[2] = 0, a[3] = 0, a[4] = 0));
+ // T (5, 5, 3, (a[0] = '1', a[1] = '2', a[2] = '3', a[3] = 0, a[4] = 0));
+ T (5, 5, 4, (a[0] = '1', a[1] = '2', a[2] = '3', a[3] = '4', a[4] = 0));
+}
+
+
+/* { dg-final { scan-tree-dump-times "strlen" 0 "optimized" } }
+ { dg-final { scan-tree-dump-times "_not_eliminated_" 0 "optimized" } } */
return 0;
}
-/* On non-strict-align targets we inline the memcpy that strcat is turned
- into and end up with a short typed load / store which strlenopt is not
- able to analyze. */
-
-/* { dg-final { scan-tree-dump-times "strlen \\(" 0 "strlen" { xfail non_strict_align } } } */
-/* { dg-final { scan-tree-dump-times "memcpy \\(" 2 "strlen" { target { non_strict_align } } } } */
-/* { dg-final { scan-tree-dump-times "memcpy \\(" 4 "strlen" { target { ! non_strict_align } } } } */
+/* { dg-final { scan-tree-dump-times "strlen \\(" 0 "strlen" } } */
/* { dg-final { scan-tree-dump-times "strcpy \\(" 0 "strlen" } } */
/* { dg-final { scan-tree-dump-times "strcat \\(" 0 "strlen" } } */
/* { dg-final { scan-tree-dump-times "strchr \\(" 0 "strlen" } } */
}
}
-/* If RHS, either directly or indirectly, refers to a string of constant
- length, return the length. Otherwise, if it refers to a character
- constant, return 1 if the constant is non-zero and 0 if it is nul.
- Otherwise, return a negative value. */
+/* Describes recursion limits used by count_nonzero_bytes. */
-static HOST_WIDE_INT
-get_min_string_length (tree rhs, bool *full_string_p)
+class ssa_name_limit_t
{
- if (INTEGRAL_TYPE_P (TREE_TYPE (rhs)))
+ bitmap visited; /* Bitmap of visited SSA_NAMEs. */
+ unsigned ssa_def_max; /* Longest chain of SSA_NAMEs to follow. */
+
+ /* Not copyable or assignable. */
+ ssa_name_limit_t (ssa_name_limit_t&);
+ void operator= (ssa_name_limit_t&);
+
+ public:
+
+ ssa_name_limit_t ()
+ : visited (NULL),
+ ssa_def_max (PARAM_VALUE (PARAM_SSA_NAME_DEF_CHAIN_LIMIT)) { }
+
+ int next_ssa_name (tree);
+
+ ~ssa_name_limit_t ()
{
- if (tree_expr_nonzero_p (rhs))
+ if (visited)
+ BITMAP_FREE (visited);
+ }
+};
+
+/* If the SSA_NAME has already been "seen" return a positive value.
+ Otherwise add it to VISITED. If the SSA_NAME limit has been
+ reached, return a negative value. Otherwise return zero. */
+
+int ssa_name_limit_t::next_ssa_name (tree ssa_name)
+{
+ if (!visited)
+ visited = BITMAP_ALLOC (NULL);
+
+ /* Return a positive value if SSA_NAME has already been visited. */
+ if (!bitmap_set_bit (visited, SSA_NAME_VERSION (ssa_name)))
+ return 1;
+
+ /* Return a negative value to let caller avoid recursing beyond
+ the specified limit. */
+ if (ssa_def_max == 0)
+ return -1;
+
+ --ssa_def_max;
+
+ return 0;
+}
+
+/* Determine the minimum and maximum number of leading non-zero bytes
+ in the representation of EXP and set LENRANGE[0] and LENRANGE[1]
+ to each. Set LENRANGE[2] to the total number of bytes in
+ the representation. Set *NULTREM if the representation contains
+ a zero byte, and set *ALLNUL if all the bytes are zero. Avoid
+ recursing deeper than the limits in SNLIM allow. Return true
+ on success and false otherwise. */
+
+static bool
+count_nonzero_bytes (tree exp, unsigned lenrange[3], bool *nulterm,
+ bool *allnul, bool *allnonnul, ssa_name_limit_t &snlim)
+{
+ if (TREE_CODE (exp) == SSA_NAME)
+ {
+ /* Handle a single-character specially. */
+ tree type = TREE_TYPE (exp);
+ if (TREE_CODE (type) == INTEGER_TYPE
+ && TYPE_MODE (type) == TYPE_MODE (char_type_node)
+ && TYPE_PRECISION (type) == TYPE_PRECISION (char_type_node))
{
- *full_string_p = false;
- return 1;
+ /* Determine if the character EXP is known to be non-zero
+ (even if its exact value is not known) and if so, recurse
+ once to set the range, etc. */
+ if (tree_expr_nonzero_p (exp))
+ return count_nonzero_bytes (build_int_cst (type, 1), lenrange,
+ nulterm, allnul, allnonnul, snlim);
+ /* Don't know whether EXP is or isn't nonzero. */
+ return false;
}
- *full_string_p = true;
- return 0;
+ gimple *stmt = SSA_NAME_DEF_STMT (exp);
+ if (gimple_code (stmt) != GIMPLE_PHI)
+ return false;
+
+ /* Avoid processing an SSA_NAME that has already been visited
+ or if an SSA_NAME limit has been reached. Indicate success
+ if the former and failure if the latter. */
+ if (int res = snlim.next_ssa_name (exp))
+ return res > 0;
+
+ /* Determine the minimum and maximum from the PHI arguments. */
+ unsigned int n = gimple_phi_num_args (stmt);
+ for (unsigned i = 0; i != n; i++)
+ {
+ tree def = gimple_phi_arg_def (stmt, i);
+ if (!count_nonzero_bytes (def, lenrange, nulterm, allnul, allnonnul,
+ snlim))
+ return false;
+ }
+
+ return true;
}
- if (TREE_CODE (rhs) == MEM_REF
- && integer_zerop (TREE_OPERAND (rhs, 1)))
+ /* Offset from the beginning of the representation bytes, a pointer
+ to the representation, and the number of bytes of the representation
+ to consider (may be less than the object size for MEM_REF). */
+ unsigned HOST_WIDE_INT offset = 0;
+ const char *prep = NULL;
+ unsigned nbytes = 0;
+
+ if (TREE_CODE (exp) == MEM_REF)
{
- rhs = TREE_OPERAND (rhs, 0);
- if (TREE_CODE (rhs) == ADDR_EXPR)
- {
- tree rhs_addr = rhs;
+ /* If the MEM_REF operand is the address of an object such as
+ a string or integer, extract it and the offset into it. */
+ tree arg = TREE_OPERAND (exp, 0);
+ if (TREE_CODE (arg) != ADDR_EXPR)
+ return false;
+
+ tree off = TREE_OPERAND (exp, 1);
+ if (TREE_CODE (off) != INTEGER_CST
+ || !tree_fits_uhwi_p (off))
+ return false;
- rhs = TREE_OPERAND (rhs, 0);
- if (TREE_CODE (rhs) != STRING_CST)
+ offset = tree_to_uhwi (off);
+ if (INT_MAX < offset)
+ return false;
+
+ /* The size of the MEM_REF access determines the number of bytes. */
+ tree type = TREE_TYPE (exp);
+ if (tree typesize = TYPE_SIZE_UNIT (type))
+ nbytes = tree_to_uhwi (typesize);
+
+ if (offset == 0 && TREE_CODE (exp) != STRING_CST)
+ {
+ int idx = get_stridx (arg);
+ if (idx > 0)
{
- int idx = get_stridx (rhs_addr);
- if (idx > 0)
+ strinfo *si = get_strinfo (idx);
+ if (si && tree_fits_shwi_p (si->nonzero_chars))
{
- strinfo *si = get_strinfo (idx);
- if (si
- && tree_fits_shwi_p (si->nonzero_chars))
- {
- *full_string_p = si->full_string_p;
- return tree_to_shwi (si->nonzero_chars);
- }
+ unsigned len = tree_to_shwi (si->nonzero_chars);
+ if (len < lenrange[0])
+ lenrange[0] = len;
+ if (lenrange[1] < len)
+ lenrange[1] = len;
+
+ if (!si->full_string_p)
+ *nulterm = false;
+
+ /* Since only the length of the string are known and
+ its contents, clear ALLNUL and ALLNONNUL purely on
+ the basis of the length. */
+ if (len)
+ *allnul = false;
+ else
+ *allnonnul = false;
+ return true;
}
}
}
+
+ /* Proceed to extract the object representation below. */
+ exp = TREE_OPERAND (arg, 0);
}
- if (TREE_CODE (rhs) == VAR_DECL
- && TREE_READONLY (rhs))
- rhs = DECL_INITIAL (rhs);
+ if (TREE_CODE (exp) == VAR_DECL && TREE_READONLY (exp))
+ {
+ exp = DECL_INITIAL (exp);
+ if (!exp)
+ return false;
+ }
- if (rhs && TREE_CODE (rhs) == STRING_CST)
+ if (TREE_CODE (exp) == STRING_CST)
{
- HOST_WIDE_INT len = strlen (TREE_STRING_POINTER (rhs));
- *full_string_p = len < TREE_STRING_LENGTH (rhs);
- return len;
+ /* Set PREP and NBYTES to the string representation. */
+ gcc_assert (offset <= INT_MAX);
+
+ if (!nbytes)
+ {
+ /* Unless NBYTES has already been determined above from
+ MEM_REF, set it here. It includes all internal nuls,
+ including the terminating one if the string has one. */
+ nbytes = TREE_STRING_LENGTH (exp);
+ if (nbytes <= offset)
+ return false;
+ }
+
+ prep = TREE_STRING_POINTER (exp) + offset;
}
- return -1;
+ unsigned char buf[256];
+ if (!prep)
+ {
+ /* Try to extract the representation of the constant object. */
+ nbytes = native_encode_expr (exp, buf, sizeof buf, -1);
+ if (!nbytes)
+ return false;
+
+ prep = reinterpret_cast <char *>(buf);
+ }
+
+ /* Compute the number of leading nonzero bytes in the representation
+ and update the minimum and maximum. */
+ unsigned n = strnlen (prep, nbytes);
+
+ if (n < lenrange[0])
+ lenrange[0] = n;
+ if (lenrange[1] < n)
+ lenrange[1] = n;
+
+ /* Set the size of the representation. */
+ if (lenrange[2] < nbytes)
+ lenrange[2] = nbytes;
+
+ /* Clear NULTERM if none of the bytes is zero. */
+ if (n == nbytes)
+ *nulterm = false;
+
+ if (n)
+ {
+ /* When the initial number of non-zero bytes N is non-zero, reset
+ *ALLNUL; if N is less than that the size of the representation
+ also clear *ALLNONNUL. */
+ *allnul = false;
+ if (n < nbytes)
+ *allnonnul = false;
+ }
+ else if (*allnul || *allnonnul)
+ {
+ *allnonnul = false;
+
+ if (*allnul)
+ {
+ /* When either ALLNUL is set and N is zero, also determine
+ whether all subsequent bytes after the first one (which
+ is nul) are zero or nonzero and clear ALLNUL if not. */
+ for (const char *p = prep; p != prep + nbytes; ++p)
+ if (*p)
+ {
+ *allnul = false;
+ break;
+ }
+ }
+ }
+
+ return true;
+}
+
+/* Same as above except with an implicit SSA_NAME limit. */
+
+static bool
+count_nonzero_bytes (tree exp, unsigned lenrange[3], bool *nulterm,
+ bool *allnul, bool *allnonnul)
+{
+ /* Set to optimistic values so the caller doesn't have to worry about
+ initializing these and to what. On success, the function will clear
+ these if it determines their values are different but being recursive
+ it never sets either to true. On failure, their values are
+ unspecified. */
+ *nulterm = true;
+ *allnul = true;
+ *allnonnul = true;
+
+ ssa_name_limit_t snlim;
+ return count_nonzero_bytes (exp, lenrange, nulterm, allnul, allnonnul, snlim);
}
-/* Handle a single or multiple character store either by single
- character assignment or by multi-character assignment from
- MEM_REF. */
+/* Handle a single or multibyte store other than by a built-in function,
+ either via a single character assignment or by multi-byte assignment
+ either via MEM_REF or via a type other than char (such as in
+ '*(int*)a = 12345'). Return true when handled. */
static bool
-handle_char_store (gimple_stmt_iterator *gsi)
+handle_store (gimple_stmt_iterator *gsi)
{
int idx = -1;
strinfo *si = NULL;
gimple *stmt = gsi_stmt (*gsi);
tree ssaname = NULL_TREE, lhs = gimple_assign_lhs (stmt);
tree rhs = gimple_assign_rhs1 (stmt);
+
+ /* The offset of the first byte in LHS modified by the the store. */
unsigned HOST_WIDE_INT offset = 0;
if (TREE_CODE (lhs) == MEM_REF
si = get_strinfo (idx);
}
+ /* Minimum and maximum leading non-zero bytes and the size of the store. */
+ unsigned lenrange[] = { UINT_MAX, 0, 0 };
+
+ /* Set to the minimum length of the string being assigned if known. */
+ unsigned HOST_WIDE_INT rhs_minlen;
+
/* STORING_NONZERO_P is true iff not all stored characters are zero.
+ STORING_ALL_NONZERO_P is true if all stored characters are zero.
STORING_ALL_ZEROS_P is true iff all stored characters are zero.
Both are false when it's impossible to determine which is true. */
bool storing_nonzero_p;
- bool storing_all_zeros_p = initializer_zerop (rhs, &storing_nonzero_p);
- if (!storing_nonzero_p)
- storing_nonzero_p = tree_expr_nonzero_p (rhs);
- bool full_string_p = storing_all_zeros_p;
+ bool storing_all_nonzero_p;
+ bool storing_all_zeros_p;
+ /* FULL_STRING_P is set when the stored sequence of characters form
+ a nul-terminated string. */
+ bool full_string_p;
- /* Set to the length of the string being assigned if known. */
- HOST_WIDE_INT rhslen;
+ const bool ranges_valid
+ = count_nonzero_bytes (rhs, lenrange, &full_string_p,
+ &storing_all_zeros_p, &storing_all_nonzero_p);
+ if (ranges_valid)
+ {
+ rhs_minlen = lenrange[0];
+ storing_nonzero_p = lenrange[1] > 0;
+
+ if (tree dstsize = compute_objsize (lhs, 1))
+ if (compare_tree_int (dstsize, lenrange[2]) < 0)
+ warning_n (gimple_location (stmt), OPT_Wstringop_overflow_,
+ lenrange[2],
+ "%Gwriting %u byte into a region of size %E",
+ "%Gwriting %u bytes into a region of size %E",
+ stmt, lenrange[2], dstsize);
+ }
+ else
+ {
+ rhs_minlen = HOST_WIDE_INT_M1U;
+ full_string_p = false;
+ storing_nonzero_p = false;
+ storing_all_zeros_p = false;
+ storing_all_nonzero_p = false;
+ }
if (si != NULL)
{
- int cmp = compare_nonzero_chars (si, offset);
- gcc_assert (offset == 0 || cmp >= 0);
- if (storing_all_zeros_p && cmp == 0 && si->full_string_p)
+ /* The corresponding element is set to 1 if the first and last
+ element, respectively, of the sequence of characters being
+ written over the string described by SI ends before
+ the terminating nul (if it has one), to zero if the nul is
+ being overwritten but not beyond, or negative otherwise. */
+ int store_before_nul[2];
+ if (ranges_valid)
+ {
+ /* The offset of the last stored byte. */
+ unsigned HOST_WIDE_INT endoff = offset + lenrange[2] - 1;
+ store_before_nul[0] = compare_nonzero_chars (si, offset);
+ if (endoff == offset)
+ store_before_nul[1] = store_before_nul[0];
+ else
+ store_before_nul[1] = compare_nonzero_chars (si, endoff);
+ }
+ else
+ {
+ store_before_nul[0] = compare_nonzero_chars (si, offset);
+ store_before_nul[1] = store_before_nul[0];
+ gcc_assert (offset == 0 || store_before_nul[0] >= 0);
+ }
+
+ if (storing_all_zeros_p
+ && store_before_nul[0] == 0
+ && store_before_nul[1] == 0
+ && si->full_string_p)
{
/* When overwriting a '\0' with a '\0', the store can be removed
if we know it has been stored in the current function. */
}
}
- if (cmp > 0
+ if (store_before_nul[1] > 0
&& storing_nonzero_p
+ && lenrange[0] == lenrange[1]
+ && lenrange[0] == lenrange[2]
&& TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE)
{
- /* Handle a single non-nul character store.
+ /* Handle a store of one or more non-nul characters that ends
+ before the terminating nul of the destination and so does
+ not affect its length
If si->nonzero_chars > OFFSET, we aren't overwriting '\0',
- and if we aren't storing '\0', we know that the length of the
- string and any other zero terminated string in memory remains
- the same. In that case we move to the next gimple statement and
- return to signal the caller that it shouldn't invalidate anything.
+ and if we aren't storing '\0', we know that the length of
+ the string and any other zero terminated string in memory
+ remains the same. In that case we move to the next gimple
+ statement and return to signal the caller that it shouldn't
+ invalidate anything.
This is benefical for cases like:
if (storing_all_zeros_p
|| storing_nonzero_p
- || (offset != 0 && cmp > 0))
+ || (offset != 0 && store_before_nul[1] > 0))
{
/* When STORING_NONZERO_P, we know that the string will start
with at least OFFSET + 1 nonzero characters. If storing
OFFSET characters long.
Otherwise, we're storing an unknown value at offset OFFSET,
- so need to clip the nonzero_chars to OFFSET. */
- bool full_string_p = storing_all_zeros_p;
- HOST_WIDE_INT len = 1;
- if (storing_nonzero_p)
- {
- /* Try to get the minimum length of the string (or
- individual character) being stored. If it fails,
- STORING_NONZERO_P guarantees it's at least 1. */
- len = get_min_string_length (rhs, &full_string_p);
- if (len < 0)
- len = 1;
- }
-
+ so need to clip the nonzero_chars to OFFSET.
+ Use the minimum length of the string (or individual character)
+ being stored if it's known. Otherwise, STORING_NONZERO_P
+ guarantees it's at least 1. */
+ HOST_WIDE_INT len
+ = storing_nonzero_p && ranges_valid ? lenrange[0] : 1;
location_t loc = gimple_location (stmt);
tree oldlen = si->nonzero_chars;
- if (cmp == 0 && si->full_string_p)
+ if (store_before_nul[1] == 0 && si->full_string_p)
/* We're overwriting the nul terminator with a nonzero or
unknown character. If the previous stmt was a memcpy,
its length may be decreased. */
HOST_WIDE_INT slen = (storing_all_zeros_p
? 0
: (storing_nonzero_p
- ? get_min_string_length (rhs, &full_string_p)
- : -1));
+ && ranges_valid ? lenrange[0] : -1));
tree len = (slen <= 0
? size_zero_node
: build_int_cst (size_type_node, slen));
}
}
else if (idx == 0
- && (rhslen = get_min_string_length (rhs, &full_string_p)) >= 0
+ && rhs_minlen < HOST_WIDE_INT_M1U
&& ssaname == NULL_TREE
&& TREE_CODE (TREE_TYPE (lhs)) == ARRAY_TYPE)
{
HOST_WIDE_INT a = int_size_in_bytes (TREE_TYPE (lhs));
- if (a > 0 && (unsigned HOST_WIDE_INT) a > (unsigned HOST_WIDE_INT) rhslen)
+ if (a > 0 && (unsigned HOST_WIDE_INT) a > rhs_minlen)
{
int idx = new_addr_stridx (lhs);
if (idx != 0)
{
si = new_strinfo (build_fold_addr_expr (lhs), idx,
- build_int_cst (size_type_node, rhslen),
+ build_int_cst (size_type_node, rhs_minlen),
full_string_p);
set_strinfo (idx, si);
si->dont_invalidate = true;
}
}
+/* Return true if TYPE corresponds to a narrow character type. */
+
+static bool
+is_char_type (tree type)
+{
+ return (TREE_CODE (type) == INTEGER_TYPE
+ && TYPE_MODE (type) == TYPE_MODE (char_type_node)
+ && TYPE_PRECISION (type) == TYPE_PRECISION (char_type_node));
+}
+
/* Attempt to check for validity of the performed access a single statement
at *GSI using string length knowledge, and to optimize it.
If the given basic block needs clean-up of EH, CLEANUP_EH is set to
}
}
else if (TREE_CODE (lhs) != SSA_NAME && !TREE_SIDE_EFFECTS (lhs))
- {
- tree type = TREE_TYPE (lhs);
- if (TREE_CODE (type) == ARRAY_TYPE)
- type = TREE_TYPE (type);
- if (TREE_CODE (type) == INTEGER_TYPE
- && TYPE_MODE (type) == TYPE_MODE (char_type_node)
- && TYPE_PRECISION (type) == TYPE_PRECISION (char_type_node))
- {
- if (! handle_char_store (gsi))
- return false;
- }
- }
+ {
+ tree type = TREE_TYPE (lhs);
+ if (TREE_CODE (type) == ARRAY_TYPE)
+ type = TREE_TYPE (type);
+
+ bool is_char_store = is_char_type (type);
+ if (!is_char_store && TREE_CODE (lhs) == MEM_REF)
+ {
+ /* To consider stores into char objects via integer types
+ other than char but not those to non-character objects,
+ determine the type of the destination rather than just
+ the type of the access. */
+ tree ref = TREE_OPERAND (lhs, 0);
+ type = TREE_TYPE (ref);
+ if (TREE_CODE (type) == POINTER_TYPE)
+ type = TREE_TYPE (type);
+ if (TREE_CODE (type) == ARRAY_TYPE)
+ type = TREE_TYPE (type);
+ if (is_char_type (type))
+ is_char_store = true;
+ }
+
+ /* Handle a single or multibyte assignment. */
+ if (is_char_store && !handle_store (gsi))
+ return false;
+ }
}
else if (gcond *cond = dyn_cast<gcond *> (stmt))
{
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