[PATCH] aarch64: Do not alter force_reg returned rtx expanding pauth builtins

[Andrea Corallo]

Hi all,

having a look for force_reg returned rtx later on modified I've found
this other case in `aarch64_general_expand_builtin` while expanding 
pointer authentication builtins.

Regtested and bootsraped on aarch64-linux-gnu.

Okay for trunk?

  Andrea


>From 8869ee04e3788fdec86aa7e5a13e2eb477091d0e Mon Sep 17 00:00:00 2001
From: Andrea Corallo <andrea.cora...@arm.com>
Date: Mon, 21 Sep 2020 13:52:45 +0100
Subject: [PATCH] aarch64: Do not alter force_reg returned rtx expanding pauth
 builtins

2020-09-21  Andrea Corallo  <andrea.cora...@arm.com>

        * config/aarch64/aarch64-builtins.c
        (aarch64_general_expand_builtin): Do not alter value on a
        force_reg returned rtx.
---
 gcc/config/aarch64/aarch64-builtins.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/gcc/config/aarch64/aarch64-builtins.c 
b/gcc/config/aarch64/aarch64-builtins.c
index b787719cf5e..a77718ccfac 100644
--- a/gcc/config/aarch64/aarch64-builtins.c
+++ b/gcc/config/aarch64/aarch64-builtins.c
@@ -2079,10 +2079,10 @@ aarch64_general_expand_builtin (unsigned int fcode, 
tree exp, rtx target,
       arg0 = CALL_EXPR_ARG (exp, 0);
       op0 = force_reg (Pmode, expand_normal (arg0));
 
-      if (!target)
+      if (!(target
+           && REG_P (target)
+           && GET_MODE (target) == Pmode))
        target = gen_reg_rtx (Pmode);
-      else
-       target = force_reg (Pmode, target);
 
       emit_move_insn (target, op0);
 
-- 
2.17.1