From: Jakub Jelinek <jakub@redhat.com>
Date: Mon, 25 Jun 2018 17:47:56 +0000 (+0200)
Subject: backport: re PR rtl-optimization/85300 (ICE in exact_int_to_float_conversion_p, at... 
X-Git-Tag: releases/gcc-6.5.0~189
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e313c255072ee6634d08f2983897d13f5f9b775d;p=thirdparty%2Fgcc.git

backport: re PR rtl-optimization/85300 (ICE in exact_int_to_float_conversion_p, at simplify-rtx.c:895)

	Backported from mainline
	2018-04-10  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/85300
	* combine.c (subst): Handle subst of CONST_SCALAR_INT_P new_rtx also
	into FLOAT and UNSIGNED_FLOAT like ZERO_EXTEND, return a CLOBBER if
	simplify_unary_operation fails.

	* gcc.dg/pr85300.c: New test.

From-SVN: r262096
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d5e68d916467..c204f20647ab 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,13 @@
 2018-06-25  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2018-04-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/85300
+	* combine.c (subst): Handle subst of CONST_SCALAR_INT_P new_rtx also
+	into FLOAT and UNSIGNED_FLOAT like ZERO_EXTEND, return a CLOBBER if
+	simplify_unary_operation fails.
+
 	2018-04-07  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/85257
diff --git a/gcc/combine.c b/gcc/combine.c
index 8ffb21dc10a8..b6024bf075d8 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -5435,11 +5435,15 @@ subst (rtx x, rtx from, rtx to, int in_dest, int in_cond, int unique_copy)
 		    x = gen_rtx_CLOBBER (mode, const0_rtx);
 		}
 	      else if (CONST_SCALAR_INT_P (new_rtx)
-		       && GET_CODE (x) == ZERO_EXTEND)
+		       && (GET_CODE (x) == ZERO_EXTEND
+			   || GET_CODE (x) == FLOAT
+			   || GET_CODE (x) == UNSIGNED_FLOAT))
 		{
-		  x = simplify_unary_operation (ZERO_EXTEND, GET_MODE (x),
-						new_rtx, GET_MODE (XEXP (x, 0)));
-		  gcc_assert (x);
+		  x = simplify_unary_operation (GET_CODE (x), GET_MODE (x),
+						new_rtx,
+						GET_MODE (XEXP (x, 0)));
+		  if (!x)
+		    return gen_rtx_CLOBBER (VOIDmode, const0_rtx);
 		}
 	      else
 		SUBST (XEXP (x, i), new_rtx);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 07ca2480ba5a..92d3b5aaeb35 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -3,6 +3,9 @@
 	Backported from mainline
 	2018-04-10  Jakub Jelinek  <jakub@redhat.com>
 
+	PR rtl-optimization/85300
+	* gcc.dg/pr85300.c: New test.
+
 	PR fortran/85313
 	* gfortran.dg/gomp/pr85313.f90: New test.
 
diff --git a/gcc/testsuite/gcc.dg/pr85300.c b/gcc/testsuite/gcc.dg/pr85300.c
new file mode 100644
index 000000000000..87a30b8d419a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr85300.c
@@ -0,0 +1,16 @@
+/* PR rtl-optimization/85300 */
+/* { dg-do compile } */
+/* { dg-options "-O1 -g -funroll-all-loops -fno-tree-ter -fno-web" } */
+
+void
+foo (double x, unsigned char y)
+{
+  while ((int) x < 1)
+    {
+      float a;
+
+      a = y | 0x100;
+      y = 0;
+      x = a;
+    }
+}