From: Ian Lance Taylor <ian@gcc.gnu.org>
Date: Sat, 28 Feb 2004 13:36:28 +0000 (+0000)
Subject: re PR rtl-optimization/7871 (ICE on legal code, global register variables problems)
X-Git-Tag: releases/gcc-3.3.4~222
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=47dbc1d8197bdf35433d1d19b68ed5547a1e1ee7;p=thirdparty%2Fgcc.git

re PR rtl-optimization/7871 (ICE on legal code, global register variables problems)

	PR optimization/7871
	* flow.c (mark_set_1): Don't add LOG_LINKS for global registers
	from or to call insns.
	(propagate_one_insn): Interpret calls as setting global	registers,
	not merely clobbering them.

From-SVN: r78618
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4e0768eab95d..3392469efa9e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2004-02-27  Ian Lance Taylor  <ian@wasabisystems.com>
+
+	PR optimization/7871
+	* flow.c (mark_set_1): Don't add LOG_LINKS for global registers
+	from or to call insns.	
+
+2004-02-27  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	PR optimization/7871
+	* flow.c (propagate_one_insn): Interpret calls as setting global
+	registers, not merely clobbering them.
+
 2004-02-26  Richard Earnshaw  <rearnsha@arm.com>
 	Daniel Jacobowitz  <drow@mvista.com>
 
diff --git a/gcc/flow.c b/gcc/flow.c
index 7882b25ae9a8..c5699b77e4d3 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -1799,8 +1799,9 @@ propagate_one_insn (pbi, insn)
 					      current_function_return_rtx,
 					      (rtx *) 0)))
 	      {
+		enum rtx_code code = global_regs[i] ? SET : CLOBBER;
 		/* We do not want REG_UNUSED notes for these registers.  */
-		mark_set_1 (pbi, CLOBBER, regno_reg_rtx[i], cond, insn,
+		mark_set_1 (pbi, code, regno_reg_rtx[i], cond, insn,
 			    pbi->flags & ~(PROP_DEATH_NOTES | PROP_REG_INFO));
 	      }
 	}
@@ -2813,10 +2814,18 @@ mark_set_1 (pbi, code, reg, cond, insn, flags)
 		     in ASM_OPERANDs.  If these registers get replaced,
 		     we might wind up changing the semantics of the insn,
 		     even if reload can make what appear to be valid
-		     assignments later.  */
+		     assignments later.
+
+		     We don't build a LOG_LINK for global registers to
+		     or from a function call.  We don't want to let
+		     combine think that it knows what is going on with
+		     global registers.  */
 		  if (y && (BLOCK_NUM (y) == blocknum)
 		      && (regno_first >= FIRST_PSEUDO_REGISTER
-			  || asm_noperands (PATTERN (y)) < 0))
+			  || (asm_noperands (PATTERN (y)) < 0
+			      && ! ((GET_CODE (insn) == CALL_INSN
+				     || GET_CODE (y) == CALL_INSN)
+				    && global_regs[regno_first]))))
 		    LOG_LINKS (y) = alloc_INSN_LIST (insn, LOG_LINKS (y));
 		}
 	    }