PR target/43546

	* expr.c (compress_float_constant): If x is a hard register,
	extend into a pseudo and then move to x.

	* gcc.target/i386/pr43546.c: New test.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@207757 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 11 insertions, 2 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index f6708da20d9..29ce694704c 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -3726,12 +3726,21 @@ compress_float_constant (rtx x, rtx y)
 	 into a new pseudo.  This constant may be used in different modes,
 	 and if not, combine will put things back together for us.  */
       trunc_y = force_reg (srcmode, trunc_y);
-      emit_unop_insn (ic, x, trunc_y, UNKNOWN);
+
+      /* If x is a hard register, perform the extension into a pseudo,
+	 so that e.g. stack realignment code is aware of it.  */
+      rtx target = x;
+      if (REG_P (x) && HARD_REGISTER_P (x))
+	target = gen_reg_rtx (dstmode);
+
+      emit_unop_insn (ic, target, trunc_y, UNKNOWN);
       last_insn = get_last_insn ();
 
-      if (REG_P (x))
+      if (REG_P (target))
 	set_unique_reg_note (last_insn, REG_EQUAL, y);
 
+      if (target != x)
+	return emit_move_insn (x, target);
       return last_insn;
     }