From: Renlin Li <renlin.li@arm.com>
Date: Mon, 9 Nov 2015 17:01:00 +0000 (+0000)
Subject: [PATCH][REE]Backport "Fix register corruption bug in ree".
X-Git-Tag: releases/gcc-4.9.4~519
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b6b6a3bcdcb554a8cf6173afc522bf2950aa31e9;p=thirdparty%2Fgcc.git

[PATCH][REE]Backport "Fix register corruption bug in ree".

Ensure inserted copy don't change the number of hard registers.

2015-11-09  Renlin Li  <renlin.li@arm.com>

	Backport from mainline
	2014-09-12  Wilco Dijkstra  <wilco.dijkstra@arm.com>

	* gcc/ree.c (combine_reaching_defs): Ensure inserted copy don't change
	the number of hard registers.

From-SVN: r230032
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b00b1657e02c..07fbdb9370c7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2015-11-09  Renlin Li  <renlin.li@arm.com>
+
+	Backport from mainline
+	2014-09-12  Wilco Dijkstra  <wilco.dijkstra@arm.com>
+
+	* gcc/ree.c (combine_reaching_defs): Ensure inserted copy don't change
+	the number of hard registers.
+
 2015-11-02  Martin Jambor  <mjambor@suse.cz>
 
 	Backport from mainline
diff --git a/gcc/ree.c b/gcc/ree.c
index 67fc9c3b0fb4..7d00d816d400 100644
--- a/gcc/ree.c
+++ b/gcc/ree.c
@@ -793,6 +793,14 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
       if (state->modified[INSN_UID (cand->insn)].kind != EXT_MODIFIED_NONE)
 	return false;
 
+      enum machine_mode dst_mode = GET_MODE (SET_DEST (PATTERN (cand->insn)));
+      rtx src_reg = get_extended_src_reg (SET_SRC (PATTERN (cand->insn)));
+
+      /* Ensure the number of hard registers of the copy match.  */
+      if (HARD_REGNO_NREGS (REGNO (src_reg), dst_mode)
+	  != HARD_REGNO_NREGS (REGNO (src_reg), GET_MODE (src_reg)))
+	return false;
+
       /* There's only one reaching def.  */
       rtx def_insn = state->defs_list[0];
 
@@ -842,7 +850,7 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
       start_sequence ();
       rtx pat = PATTERN (cand->insn);
       rtx new_dst = gen_rtx_REG (GET_MODE (SET_DEST (pat)),
-                                 REGNO (XEXP (SET_SRC (pat), 0)));
+                                 REGNO (get_extended_src_reg (SET_SRC (pat))));
       rtx new_src = gen_rtx_REG (GET_MODE (SET_DEST (pat)),
                                  REGNO (SET_DEST (pat)));
       emit_move_insn (new_dst, new_src);