From: liuhongt <hongtao.liu@intel.com>
Date: Mon, 6 Sep 2021 09:09:38 +0000 (+0800)
Subject: Avoid FROM being overwritten in expand_fix.
X-Git-Tag: basepoints/gcc-13~4945
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=93e6809459f34ca7b5928f1729246b2e9dfb3eb4;p=thirdparty%2Fgcc.git

Avoid FROM being overwritten in expand_fix.

For the conversion from _Float16 to int, if the corresponding optab
does not exist, the compiler will try the wider mode (SFmode here),
but when floatsfsi exists but FAIL, FROM will be rewritten, which
leads to a PR runtime error.

gcc/ChangeLog:

	PR middle-end/102182
	* optabs.c (expand_fix): Add from1 to avoid from being
	overwritten.

gcc/testsuite/ChangeLog:

	PR middle-end/102182
	* gcc.target/i386/pr101282.c: New test.
---

diff --git a/gcc/optabs.c b/gcc/optabs.c
index ebed78fda3fb..019bbb628825 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -5488,20 +5488,21 @@ expand_fix (rtx to, rtx from, int unsignedp)
 	if (icode != CODE_FOR_nothing)
 	  {
 	    rtx_insn *last = get_last_insn ();
+	    rtx from1 = from;
 	    if (fmode != GET_MODE (from))
-	      from = convert_to_mode (fmode, from, 0);
+	      from1 = convert_to_mode (fmode, from, 0);
 
 	    if (must_trunc)
 	      {
-		rtx temp = gen_reg_rtx (GET_MODE (from));
-		from = expand_unop (GET_MODE (from), ftrunc_optab, from,
-				    temp, 0);
+		rtx temp = gen_reg_rtx (GET_MODE (from1));
+		from1 = expand_unop (GET_MODE (from1), ftrunc_optab, from1,
+				     temp, 0);
 	      }
 
 	    if (imode != GET_MODE (to))
 	      target = gen_reg_rtx (imode);
 
-	    if (maybe_emit_unop_insn (icode, target, from,
+	    if (maybe_emit_unop_insn (icode, target, from1,
 				      doing_unsigned ? UNSIGNED_FIX : FIX))
 	      {
 		if (target != to)
diff --git a/gcc/testsuite/gcc.target/i386/pr101282.c b/gcc/testsuite/gcc.target/i386/pr101282.c
new file mode 100644
index 000000000000..2148b9294ef1
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr101282.c
@@ -0,0 +1,18 @@
+/* { dg-do run { target { ia32 } } } */
+/* { dg-options "-Os -march=i686 -mfpmath=sse -msse2" } */
+
+#include<stdlib.h>
+int
+main (void)
+{
+  static volatile unsigned int ivin, ivout;
+  static volatile _Float16 fv1, fv2;
+  ivin = ((unsigned int)1);
+  fv1 = ((unsigned int)1);
+  fv2 = ivin;
+  ivout = fv2;
+  if (ivout != ((unsigned int)1))
+    abort ();
+
+  exit (0);
+}