2014-07-28 Richard Biener <rguenther@suse.de>

	PR middle-end/52478
	* optabs.c (gen_int_libfunc): For -ftrapv libfuncs make
	sure to register SImode ones, not only >= word_mode ones.
	* expr.c (expand_expr_real_2): When expanding -ftrapv
	binops do not use OPTAB_LIB_WIDEN.

	* gcc.dg/torture/ftrapv-1.c: New testcase.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@213117 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 59 insertions, 3 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 56d3b250a03..fcb95b1a9cb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2014-07-28  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/52478
+	* optabs.c (gen_int_libfunc): For -ftrapv libfuncs make
+	sure to register SImode ones, not only >= word_mode ones.
+	* expr.c (expand_expr_real_2): When expanding -ftrapv
+	binops do not use OPTAB_LIB_WIDEN.
+
 2014-07-28  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	PR middle-end/61919
diff --git a/gcc/expr.c b/gcc/expr.c
index d8328eebfbf..de0da345198 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -9212,7 +9212,9 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
   if (modifier == EXPAND_STACK_PARM)
     target = 0;
   temp = expand_binop (mode, this_optab, op0, op1, target,
-		       unsignedp, OPTAB_LIB_WIDEN);
+		       unsignedp,
+		       trapv_binoptab_p (this_optab)
+		       ? OPTAB_LIB : OPTAB_LIB_WIDEN);
   gcc_assert (temp);
   /* Bitwise operations do not need bitfield reduction as we expect their
      operands being properly truncated.  */
diff --git a/gcc/optabs.c b/gcc/optabs.c
index 7ee84c4348c..c7bd9d07485 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -5559,13 +5559,17 @@ gen_int_libfunc (optab optable, const char *opname, char suffix,
 		 enum machine_mode mode)
 {
   int maxsize = 2 * BITS_PER_WORD;
+  int minsize = BITS_PER_WORD;
 
   if (GET_MODE_CLASS (mode) != MODE_INT)
     return;
   if (maxsize < LONG_LONG_TYPE_SIZE)
     maxsize = LONG_LONG_TYPE_SIZE;
-  if (GET_MODE_CLASS (mode) != MODE_INT
-      || GET_MODE_BITSIZE (mode) < BITS_PER_WORD
+  if (minsize > INT_TYPE_SIZE
+      && (trapv_binoptab_p (optable)
+	  || trapv_unoptab_p (optable)))
+    minsize = INT_TYPE_SIZE;
+  if (GET_MODE_BITSIZE (mode) < minsize
       || GET_MODE_BITSIZE (mode) > maxsize)
     return;
   gen_libfunc (optable, opname, suffix, mode);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 68499d9eed0..014896c627c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2014-07-28  Richard Biener  <rguenther@suse.de>
 
+	PR middle-end/52478
+	* gcc.dg/torture/ftrapv-1.c: New testcase.
+
+2014-07-28  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/61921
 	* gfortran.dg/pr61921.f90: New testcase.
 
diff --git a/gcc/testsuite/gcc.dg/torture/ftrapv-1.c b/gcc/testsuite/gcc.dg/torture/ftrapv-1.c
new file mode 100644
index 00000000000..4fdccd887ae
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/ftrapv-1.c
@@ -0,0 +1,37 @@
+/* { dg-do run } */
+/* { dg-additional-options "-ftrapv" } */
+/* { dg-require-effective-target trapping } */
+/* { dg-require-fork } */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+/* Verify SImode operations properly trap.  PR middle-end/52478  */
+
+/* Disallow inlining/cloning which would constant propagate and trigger
+   unrelated bugs.  */
+
+int __attribute__((noinline,noclone))
+iaddv (int a, int b)
+{
+  return a + b;
+}
+
+int main(void)
+{
+  pid_t child = fork ();
+  int status = 0;
+  if (child == 0)
+    {
+      volatile int x = iaddv (__INT_MAX__, 1);
+      exit (0);
+    }
+  else if (child == -1)
+    return 0;
+  if (wait (&status) == child 
+      && status == 0)
+    abort ();
+  return 0;
+}