re PR tree-optimization/79327 (wrong code at -O2 and -fprintf-return-value)

	PR tree-optimization/79327
	* gimple-ssa-sprintf.c (adjust_range_for_overflow): If returning
	true, always set *argmin and *argmax to TYPE_{MIN,MAX}_VALUE of
	dirtype.
	(format_integer): Use wide_int_to_tree instead of build_int_cst
	+ to_?hwi.  If argmin is NULL, just set argmin and argmax to
	TYPE_{MIN,MAX}_VALUE of argtype.  Simplify and fix computation
	of shortest and longest sequence.

	* gcc.dg/tree-ssa/pr79327.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c
	(test_sprintf_chk_hh_nonconst): Don't expect 2 bogus warnings.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-3.c
	(test_sprintf_chk_range_schar): Adjust dg-message.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-12.c: New test.
	* gcc.c-torture/execute/pr79327.c: New test.

Co-Authored-By: Martin Sebor <msebor@redhat.com>

From-SVN: r245166

gcc/ChangeLog

+2017-02-03  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/79327
+	* gimple-ssa-sprintf.c (adjust_range_for_overflow): If returning
+	true, always set *argmin and *argmax to TYPE_{MIN,MAX}_VALUE of
+	dirtype.
+	(format_integer): Use wide_int_to_tree instead of build_int_cst
+	+ to_?hwi.  If argmin is NULL, just set argmin and argmax to
+	TYPE_{MIN,MAX}_VALUE of argtype.  Simplify and fix computation
+	of shortest and longest sequence.
+
 2017-02-03  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.c (dimode_scalar_chain::convert_reg):

gcc/gimple-ssa-sprintf.c

@@ -1014,8 +1014,8 @@ get_int_range (tree arg, tree type, HOST_WIDE_INT *pmin, HOST_WIDE_INT *pmax,
    determined by checking for the actual argument being in the range
    of the type of the directive.  If it isn't it must be assumed to
    take on the full range of the directive's type.
-   Return true when the range has been adjusted to the full unsigned
-   range of DIRTYPE, or [0, DIRTYPE_MAX], and false otherwise.  */
+   Return true when the range has been adjusted to the full range
+   of DIRTYPE, and false otherwise.  */
 
 static bool
 adjust_range_for_overflow (tree dirtype, tree *argmin, tree *argmax)
@@ -1051,20 +1051,8 @@ adjust_range_for_overflow (tree dirtype, tree *argmin, tree *argmax)
 	return false;
     }
 
-  tree dirmin = TYPE_MIN_VALUE (dirtype);
-  tree dirmax = TYPE_MAX_VALUE (dirtype);
-
-  if (TYPE_UNSIGNED (dirtype))
-    {
-      *argmin = dirmin;
-      *argmax = dirmax;
-    }
-  else
-    {
-      *argmin = integer_zero_node;
-      *argmax = dirmin;
-    }
-
+  *argmin = TYPE_MIN_VALUE (dirtype);
+  *argmax = TYPE_MAX_VALUE (dirtype);
   return true;
 }
 
@@ -1260,10 +1248,8 @@ format_integer (const directive &dir, tree arg)
       enum value_range_type range_type = get_range_info (arg, &min, &max);
       if (range_type == VR_RANGE)
 	{
-	  argmin = build_int_cst (argtype, wi::fits_uhwi_p (min)
-				  ? min.to_uhwi () : min.to_shwi ());
-	  argmax = build_int_cst (argtype, wi::fits_uhwi_p (max)
-				  ? max.to_uhwi () : max.to_shwi ());
+	  argmin = wide_int_to_tree (argtype, min);
+	  argmax = wide_int_to_tree (argtype, max);
 
 	  /* Set KNOWNRANGE if the argument is in a known subrange
 	     of the directive's type (KNOWNRANGE may be reset below).  */
@@ -1307,47 +1293,16 @@ format_integer (const directive &dir, tree arg)
 
   if (!argmin)
     {
-      /* For an unknown argument (e.g., one passed to a vararg function)
-	 or one whose value range cannot be determined, create a T_MIN
-	 constant if the argument's type is signed and T_MAX otherwise,
-	 and use those to compute the range of bytes that the directive
-	 can output.  When precision may be zero, use zero as the minimum
-	 since it results in no bytes on output (unless width is specified
-	 to be greater than 0).  */
-      bool zero = dir.prec[0] <= 0 && dir.prec[1] >= 0;
-      argmin = build_int_cst (argtype, !zero);
-
-      int typeprec = TYPE_PRECISION (dirtype);
-      int argprec = TYPE_PRECISION (argtype);
-
-      if (argprec < typeprec)
-	{
-	  if (POINTER_TYPE_P (argtype))
-	    argmax = build_all_ones_cst (argtype);
-	  else if (TYPE_UNSIGNED (argtype))
-	    argmax = TYPE_MAX_VALUE (argtype);
-	  else
-	    argmax = TYPE_MIN_VALUE (argtype);
+      if (TREE_CODE (argtype) == POINTER_TYPE)
+	{
+	  argmin = build_int_cst (pointer_sized_int_node, 0);
+	  argmax = build_all_ones_cst (pointer_sized_int_node);
 	}
       else
 	{
-	  if (POINTER_TYPE_P (dirtype))
-	    argmax = build_all_ones_cst (dirtype);
-	  else if (TYPE_UNSIGNED (dirtype))
-	    argmax = TYPE_MAX_VALUE (dirtype);
-	  else
-	    argmax = TYPE_MIN_VALUE (dirtype);
+	  argmin = TYPE_MIN_VALUE (argtype);
+	  argmax = TYPE_MAX_VALUE (argtype);
 	}
-
-      res.argmin = argmin;
-      res.argmax = argmax;
-    }
-
-  if (tree_int_cst_lt (argmax, argmin))
-    {
-      tree tmp = argmax;
-      argmax = argmin;
-      argmin = tmp;
     }
 
   /* Clear KNOWNRANGE if the range has been adjusted to the maximum
@@ -1361,34 +1316,33 @@ format_integer (const directive &dir, tree arg)
       res.argmax = argmax;
     }
 
-  /* Recursively compute the minimum and maximum from the known range,
-     taking care to swap them if the lower bound results in longer
-     output than the upper bound (e.g., in the range [-1, 0].  */
-
-  if (TYPE_UNSIGNED (dirtype))
+  /* Recursively compute the minimum and maximum from the known range.  */
+  if (TYPE_UNSIGNED (dirtype) || tree_int_cst_sgn (argmin) >= 0)
     {
-      /* For unsigned conversions/directives, use the minimum (i.e., 0
-	 or 1) and maximum to compute the shortest and longest output,
-	 respectively.  */
+      /* For unsigned conversions/directives or signed when
+	 the minimum is positive, use the minimum and maximum to compute
+	 the shortest and longest output, respectively.  */
       res.range.min = format_integer (dir, argmin).range.min;
       res.range.max = format_integer (dir, argmax).range.max;
     }
-  else
+  else if (tree_int_cst_sgn (argmax) < 0)
     {
-      /* For signed conversions/directives, use the maximum (i.e., 0)
-	 to compute the shortest output and the minimum (i.e., TYPE_MIN)
-	 to compute the longest output.  This is important when precision
-	 is specified but unknown because otherwise both output lengths
-	 would reflect the largest possible precision (i.e., INT_MAX).  */
+      /* For signed conversions/directives if maximum is negative,
+	 use the minimum as the longest output and maximum as the
+	 shortest output.  */
       res.range.min = format_integer (dir, argmax).range.min;
       res.range.max = format_integer (dir, argmin).range.max;
     }
-
-  if (res.range.max < res.range.min)
+  else
     {
-      unsigned HOST_WIDE_INT tmp = res.range.max;
-      res.range.max = res.range.min;
-      res.range.min = tmp;
+      /* Otherwise, 0 is inside of the range and minimum negative.  Use 0
+	 as the shortest output and for the longest output compute the
+	 length of the output of both minimum and maximum and pick the
+	 longer.  */
+      unsigned HOST_WIDE_INT max1 = format_integer (dir, argmin).range.max;
+      unsigned HOST_WIDE_INT max2 = format_integer (dir, argmax).range.max;
+      res.range.min = format_integer (dir, integer_zero_node).range.min;
+      res.range.max = MAX (max1, max2);
     }
 
   res.range.likely = res.knownrange ? res.range.max : res.range.min;

gcc/testsuite/ChangeLog

 2017-02-03  Jakub Jelinek  <jakub@redhat.com>
+	    Martin Sebor  <msebor@redhat.com>
+
+	PR tree-optimization/79327
+	* gcc.dg/tree-ssa/pr79327.c: New test.
+	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c
+	(test_sprintf_chk_hh_nonconst): Don't expect 2 bogus warnings.
+	* gcc.dg/tree-ssa/builtin-sprintf-warn-3.c
+	(test_sprintf_chk_range_schar): Adjust dg-message.
+	* gcc.dg/tree-ssa/builtin-sprintf-warn-12.c: New test.
+	* gcc.c-torture/execute/pr79327.c: New test.
+
+2017-02-03  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/79354
 	* gcc.target/powerpc/pr79354.c: New test.

gcc/testsuite/gcc.c-torture/execute/pr79327.c

+/* PR tree-optimization/79327 */
+/* { dg-require-effective-target c99_runtime } */
+
+volatile int a;
+
+int
+main (void)
+{
+  int i;
+  char buf[64];
+  if (__builtin_sprintf (buf, "%#hho", a) != 1)
+    __builtin_abort ();
+  if (__builtin_sprintf (buf, "%#hhx", a) != 1)
+    __builtin_abort ();
+  a = 1;
+  if (__builtin_sprintf (buf, "%#hho", a) != 2)
+    __builtin_abort ();
+  if (__builtin_sprintf (buf, "%#hhx", a) != 3)
+    __builtin_abort ();
+  a = 127;
+  if (__builtin_sprintf (buf, "%#hho", a) != 4)
+    __builtin_abort ();
+  if (__builtin_sprintf (buf, "%#hhx", a) != 4)
+    __builtin_abort ();
+  return 0;
+}

gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-1.c

@@ -1151,8 +1151,8 @@ void test_sprintf_chk_hh_nonconst (int w, int p, int a)
   T (2, "% hhu",        a);     /* { dg-warning ". . flag used with .%u." } */
   T (2, "% hhx",        a);     /* { dg-warning ". . flag used with .%x." } */
 
-  T (2, "%#hho",        a);     /* { dg-warning "nul past the end" } */
-  T (2, "%#hhx",        a);     /* { dg-warning ".%#hhx. directive writing between 3 and . bytes into a region of size 2" } */
+  T (2, "%#hho",        a);
+  T (2, "%#hhx",        a);
 
   T (3, "%0hhd",        a);
   T (3, "%1hhd",        a);

gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-3.c

@@ -198,7 +198,7 @@ void test_sprintf_chk_range_schar (void)
   /* { dg-message "directive argument in the range \\\[1024, 1034\\\]" "note" { target *-*-* } .-1 } */
 
   T ( 0, "%hhi", R (1024, 2035));   /* { dg-warning ".%hhi. directive writing between 1 and 4 bytes into a region of size 0" } */
-  /* { dg-message "using the range \\\[0, -128\\\] for directive argument" "note" { target *-*-* } .-1 } */
+  /* { dg-message "using the range \\\[-128, 127\\\] for directive argument" "note" { target *-*-* } .-1 } */
 
 #undef R
 #define R(min, max) range_schar (min, max)

gcc/testsuite/gcc.dg/tree-ssa/pr79327.c

+/* PR tree-optimization/79327 - wrong code at -O2 and -fprintf-return-value
+   { dg-do run }
+   { dg-options "-O2 -Wall" }  */
+
+volatile int a, b = -1;
+char buf[64];
+
+#define FMT "%+03d%02d"
+const char *volatile fmt = FMT;
+
+int main ()
+{
+  int c = a;
+  int d = b;
+  if (c >= -35791395 && c < 35791394 && d >= -1 && d < __INT_MAX__)
+    {
+      /* In the following the range of return values can be computed
+	 by GCC. */
+      int n1 = __builtin_sprintf (buf, FMT, c + 1, d + 1);
+      if (n1 > 7)
+	__builtin_abort ();
+
+      /* Here GCC can't see the format string so the return value
+	 must be computed by a libc call.  */
+      int n2 = __builtin_sprintf (buf, fmt, c + 1, d + 1);
+
+      if (n1 != n2)
+	__builtin_abort ();
+    }
+  return 0;
+}