gimple-fold.h (get_range_strlen): Update prototype.

	* gimple-fold.h (get_range_strlen): Update prototype.
	* builtins.c (check_access): Update call to get_range_strlen to use
	c_strlen_data pointer.   Change various variable accesses to instead
	pull data from the c_strlen_data structure.
	(check_strncat_sizes, expand_builtin_strncat): Likewise.
	* calls.c (maybe_warn_nonstring_arg): Likewise.
	* tree-ssa-strlen.c (maybe_diag_stxncpy_trunc): Likewise.  Reset
	minimum length if maximum lengh is unknown.
	* gimple-ssa-sprintf.c (get_string_length): Likewise.  Drop code
	that used c_strlen, it's no longer needed.  Restructure slightly.
	(format_string): Set unlikely range appropriately.
	* gimple-fold.c (get_range_strlen): Update comments.  Fix minor
	formatting issues.
	(get_range_strlen):  Accept c_strlen_data pointer for external
	call sites as well.  Pass through to call to internal get_range_strlen.
	Adjust minlen, maxlen and maxbound as needed.
	(get_maxval_strlen): Update comments.
	(gimple_fold_builtin_strlen):  Update call to get_range_strlen
	to use c_strlen_data pointer.  Change variable accesses to instead
	use c_strlen_data data members.

	* gcc.dg/strlenopt-40.c: Disable a couple tests.
	* gcc.dg/strlenopt-48.c: Twiddle test.
	* gcc.dg/strlenopt-59.c: New test.
	* gcc.dg/tree-ssa/builtin-snprintf-5.c: New test.
	* g++.dg/init/strlen.C: New test.

Co-Authored-By: Jeff Law <law@redhat.com>

From-SVN: r267503

4 files changed, 129 insertions, 5 deletions

diff --git a/gcc/testsuite/gcc.dg/strlenopt-40.c b/gcc/testsuite/gcc.dg/strlenopt-40.c
index f4577d6..e24b510 100644
--- a/gcc/testsuite/gcc.dg/strlenopt-40.c
+++ b/gcc/testsuite/gcc.dg/strlenopt-40.c
@@ -124,8 +124,8 @@ void elim_global_arrays (int i)
   ELIM_TRUE (strlen (a7) < sizeof a7);
 
   ELIM_TRUE (strlen (ax) != DIFF_MAX);
-  ELIM_TRUE (strlen (ax) != DIFF_MAX - 1);
-  ELIM_TRUE (strlen (ax) < DIFF_MAX - 1);
+  /* ELIM_TRUE (strlen (ax) != DIFF_MAX - 1); */
+  /* ELIM_TRUE (strlen (ax) < DIFF_MAX - 1); */
 }
 
 void elim_pointer_to_arrays (void)
diff --git a/gcc/testsuite/gcc.dg/strlenopt-48.c b/gcc/testsuite/gcc.dg/strlenopt-48.c
index 39bb32d..179edd8 100644
--- a/gcc/testsuite/gcc.dg/strlenopt-48.c
+++ b/gcc/testsuite/gcc.dg/strlenopt-48.c
@@ -11,7 +11,7 @@ void f (void)
 {
   extern char a[2][1];
   int n = strlen (a[1]);
-  if (n)
+  if (n >= sizeof a)
     abort();
 }
 
@@ -19,7 +19,7 @@ void g (void)
 {
   extern char b[3][2][1];
   int n = strlen (b[2][1]);
-  if (n)
+  if (n >= sizeof b)
     abort();
 }
 
@@ -27,7 +27,7 @@ void h (void)
 {
   extern char c[4][3][2][1];
   int n = strlen (c[3][2][1]);
-  if (n)
+  if (n >= sizeof c)
     abort();
 }
 
diff --git a/gcc/testsuite/gcc.dg/strlenopt-59.c b/gcc/testsuite/gcc.dg/strlenopt-59.c
new file mode 100644
index 0000000..9bacf87
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/strlenopt-59.c
@@ -0,0 +1,73 @@
+/* Verify that strlen() calls with constant conditional expressions are
+   eliminated as expected.
+
+   { dg-do compile }
+   { dg-options "-O1 -fdump-tree-optimized" }  */
+
+extern void abort (void);
+extern __SIZE_TYPE__ strlen (const char*);
+
+
+#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 funcation 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 (test_not_eliminated); else (void)0
+
+extern char a3[3];
+extern char a7[7];
+
+struct MemArrays { char a[7], b[9]; };
+
+struct MemArrays ma;
+
+void test_elim_condexpr (int i)
+{
+  ELIM (6 < strlen (i ? "" : "123456"));
+  ELIM (6 < strlen (i ? "123456" : ""));
+
+  ELIM (4 < strlen (i < 1 ? "a" : i == 1 ? "ab" : "abc"));
+
+  ELIM (3 < strlen (i ? "" : a3));
+  ELIM (3 < strlen (i ? a3 : "1"));
+
+  ELIM (6 < strlen (i ? "12" : a7));
+  ELIM (6 < strlen (i ? a7 : "123"));
+
+  ELIM (6 < strlen (i ? "1234" : a7));
+  ELIM (7 < strlen (i ? a7 : "1234567"));
+
+  ELIM (3 < strlen (i < 1 ? "a" : i == 1 ? "ab" : a3));
+  ELIM (3 < strlen (i < 1 ? "a" : i == 1 ? a3 : "abc"));
+  ELIM (3 < strlen (i < 1 ? a3 : i == 1 ? "a" : "abc"));
+
+  ELIM (6 < strlen (i < 1 ? "a" : i == 1 ? "ab" : a7));
+  ELIM (6 < strlen (i < 1 ? "a" : i == 1 ? a7 : "abc"));
+  ELIM (6 < strlen (i < 1 ? a7 : i == 1 ? "a" : "abc"));
+
+  ELIM (6 < strlen (i < 1 ? "a" : i == 1 ? a7 : a3));
+  ELIM (6 < strlen (i < 1 ? a7 : i == 1 ? "a" : a3));
+
+  {
+    enum { maxlen = sizeof ma - 1 };
+    ELIM (maxlen < strlen (ma.a));
+  }
+
+  {
+    enum { maxlen = sizeof ma - __builtin_offsetof (struct MemArrays, b) - 1 };
+    ELIM (maxlen < strlen (ma.b));
+  }
+}
+
+/* { dg-final { scan-tree-dump-times "test_not_eliminated_" 0 "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/builtin-snprintf-5.c b/gcc/testsuite/gcc.dg/tree-ssa/builtin-snprintf-5.c
new file mode 100644
index 0000000..ad9a99b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/builtin-snprintf-5.c
@@ -0,0 +1,51 @@
+/*
+  { dg-do compile }
+  { dg-options "-O2 -Wall -fdump-tree-optimized" } */
+
+typedef __SIZE_TYPE__ size_t;
+
+extern void abort (void);
+extern int snprintf (char*, size_t, const char*, ...);
+
+const char s0[] = "";
+const char s1[] = "a";
+const char s2[] = "ab";
+
+extern char ax[];
+extern const char* const ptr;
+
+#define CAT(x, y)      x ## y
+#define CONCAT(x, y)   CAT (x, y)
+#define TEST           CONCAT (test_on_line_, __LINE__)
+
+#define KEEP(expr) do {				\
+    if ((expr))	{				\
+      extern void TEST (void);			\
+      TEST ();					\
+    }						\
+  } while (0)
+
+
+void test_literal (int i)
+{
+  KEEP (0 < snprintf (0, 0, "%s", i ? "" : ax));
+  KEEP (1 < snprintf (0, 0, "%s", i ? ax : "1"));
+  KEEP (2 < snprintf (0, 0, "%s", i ? "12" : ptr));
+
+  KEEP (1 > snprintf (0, 0, "%s", i ? "" : ax));
+  KEEP (1 > snprintf (0, 0, "%s", i ? ax : "1"));
+  KEEP (2 > snprintf (0, 0, "%s", i ? "12" : ptr));
+}
+
+void test_cststr (int i)
+{
+  KEEP (0 < snprintf (0, 0, "%s", i ? s0 : ax));
+  KEEP (1 < snprintf (0, 0, "%s", i ? ax : s1));
+  KEEP (2 < snprintf (0, 0, "%s", i ? s2 : ptr));
+
+  KEEP (1 > snprintf (0, 0, "%s", i ? s0 : ax));
+  KEEP (1 > snprintf (0, 0, "%s", i ? ax : s1));
+  KEEP (2 > snprintf (0, 0, "%s", i ? s2 : ptr));
+}
+
+/* { dg-final { scan-tree-dump-times "test_on_line_" 12 "optimized" } } */