reload autoinc fix

[Bernd Schmidt <bernds at codesourcery dot com>]

This is PR56791. The address inside of an autoinc is reloaded, and the 
autoinc is reloaded, but the reload insns are emitted in the wrong order.

As far as I can tell, this is because find_reloads_address_1 has two 
methods of pushing a reload for an autoinc, one of them using the 
previously identified type, and the other (better one) using 
RELOAD_OTHER. If we previously reloaded an inner part of the address, 
the use of RELOAD_OTHER is mismatched and leads to the wrong order of insns.

This patch just remembers if we've pushed a reload, and forces the 
optimization to be skipped in that case. Bootstrapped and tested on 
x86_64-linux (with lra_p disabled but still somewhat pointlessly); John 
Anglin said in the PR that it tests ok on PA. Will commit in a few days 
if no objections.


Bernd

diff --git a/gcc/reload.c b/gcc/reload.c
index 2546c1b..279c4b8e 100644
--- a/gcc/reload.c
+++ b/gcc/reload.c
@@ -5557,6 +5557,7 @@ find_reloads_address_1 (enum machine_mode mode, addr_space_t as,
 
   enum reg_class context_reg_class;
   RTX_CODE code = GET_CODE (x);
+  bool reloaded_inner_of_autoinc = false;
 
   if (context == 1)
     context_reg_class = INDEX_REG_CLASS;
@@ -5844,6 +5846,7 @@ find_reloads_address_1 (enum machine_mode mode, addr_space_t as,
 		  find_reloads_address (GET_MODE (tem), &tem, XEXP (tem, 0),
 					&XEXP (tem, 0), opnum, type,
 					ind_levels, insn);
+		  reloaded_inner_of_autoinc = true;
 		  if (!rtx_equal_p (tem, orig))
 		    push_reg_equiv_alt_mem (regno, tem);
 		  /* Put this inside a new increment-expression.  */
@@ -5892,7 +5895,10 @@ find_reloads_address_1 (enum machine_mode mode, addr_space_t as,
 #endif
 		  && ! (icode != CODE_FOR_nothing
 			&& insn_operand_matches (icode, 0, equiv)
-			&& insn_operand_matches (icode, 1, equiv)))
+			&& insn_operand_matches (icode, 1, equiv))
+		  /* Using RELOAD_OTHER means we emit this and the reload we
+		     made earlier in the wrong order.  */
+		  && !reloaded_inner_of_autoinc)
 		{
 		  /* We use the original pseudo for loc, so that
 		     emit_reload_insns() knows which pseudo this