From: Jakub Jelinek <jakub@redhat.com>
Date: Tue, 16 Aug 2016 16:48:16 +0000 (+0200)
Subject: re PR middle-end/67485 (expmed.c sanitizer detects overflow)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1b13411a13e274d5e01b73704df9edd2639eedb4;p=gcc.git

re PR middle-end/67485 (expmed.c sanitizer detects overflow)

	PR middle-end/67485
	* expmed.c (expand_mult_const): Change val_so_far's type to UHWI,
	only cast it to SHWI for the final comparison.

	* gcc.c-torture/compile/pr67485.c: New test.

From-SVN: r239507
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index df133208b2c..e2bec5f87ae 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2016-08-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/67485
+	* expmed.c (expand_mult_const): Change val_so_far's type to UHWI,
+	only cast it to SHWI for the final comparison.
+
 2016-08-16  Martin Liska  <mliska@suse.cz>
 
 	PR gcov-profile/36412
diff --git a/gcc/expmed.c b/gcc/expmed.c
index 674c8f08928..1cedf023c8e 100644
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -3055,7 +3055,7 @@ expand_mult_const (machine_mode mode, rtx op0, HOST_WIDE_INT val,
 		   rtx target, const struct algorithm *alg,
 		   enum mult_variant variant)
 {
-  HOST_WIDE_INT val_so_far;
+  unsigned HOST_WIDE_INT val_so_far;
   rtx_insn *insn;
   rtx accum, tem;
   int opno;
@@ -3105,14 +3105,14 @@ expand_mult_const (machine_mode mode, rtx op0, HOST_WIDE_INT val,
 	  tem = expand_shift (LSHIFT_EXPR, mode, op0, log, NULL_RTX, 0);
 	  accum = force_operand (gen_rtx_PLUS (mode, accum, tem),
 				 add_target ? add_target : accum_target);
-	  val_so_far += HOST_WIDE_INT_1 << log;
+	  val_so_far += HOST_WIDE_INT_1U << log;
 	  break;
 
 	case alg_sub_t_m2:
 	  tem = expand_shift (LSHIFT_EXPR, mode, op0, log, NULL_RTX, 0);
 	  accum = force_operand (gen_rtx_MINUS (mode, accum, tem),
 				 add_target ? add_target : accum_target);
-	  val_so_far -= HOST_WIDE_INT_1 << log;
+	  val_so_far -= HOST_WIDE_INT_1U << log;
 	  break;
 
 	case alg_add_t2_m:
@@ -3188,7 +3188,7 @@ expand_mult_const (machine_mode mode, rtx op0, HOST_WIDE_INT val,
   nmode = GET_MODE_INNER (mode);
   val &= GET_MODE_MASK (nmode);
   val_so_far &= GET_MODE_MASK (nmode);
-  gcc_assert (val == val_so_far);
+  gcc_assert (val == (HOST_WIDE_INT) val_so_far);
 
   return accum;
 }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f39434dfc8d..f9668c9229f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2016-08-16  Jakub Jelinek  <jakub@redhat.com>
 
+	PR middle-end/67485
+	* gcc.c-torture/compile/pr67485.c: New test.
+
 	PR target/72867
 	* gcc.target/i386/pr72867.c: Add -msse to dg-options.
 
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr67485.c b/gcc/testsuite/gcc.c-torture/compile/pr67485.c
new file mode 100644
index 00000000000..05098f93fa2
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr67485.c
@@ -0,0 +1,7 @@
+/* PR middle-end/67485 */
+
+long int
+foo (long int x)
+{
+  return x * __LONG_MAX__;
+}