re PR target/42321 (NEON/VFP registers from inline assembly clobber list are…

re PR target/42321 (NEON/VFP registers from inline assembly clobber list are saved/restored incorrectly)

	PR target/42321
	* arm.c (arm_output_epilogue): Correctly match VFP pop instructions
	with their corresponding prologue pushes.

From-SVN: r157609

gcc/ChangeLog

+2010-03-21  Richard Earnshaw  <rearnsha@arm.com>
+
+	PR target/42321
+	* arm.c (arm_output_epilogue): Correctly match VFP pop instructions
+	with their corresponding prologue pushes.
+
 2010-03-20  Andrew Pinski  <pinskia@gmail.com>
 
 	PR target/43156

gcc/config/arm/arm.c

@@ -13731,24 +13731,29 @@ arm_output_epilogue (rtx sibling)
 
       if (TARGET_HARD_FLOAT && TARGET_VFP)
 	{
-	  start_reg = FIRST_VFP_REGNUM;
-	  for (reg = FIRST_VFP_REGNUM; reg < LAST_VFP_REGNUM; reg += 2)
+	  int end_reg = LAST_VFP_REGNUM + 1;
+
+	  /* Scan the registers in reverse order.  We need to match
+	     any groupings made in the prologue and generate matching
+	     pop operations.  */
+	  for (reg = LAST_VFP_REGNUM - 1; reg >= FIRST_VFP_REGNUM; reg -= 2)
 	    {
 	      if ((!df_regs_ever_live_p (reg) || call_used_regs[reg])
-		  && (!df_regs_ever_live_p (reg + 1) || call_used_regs[reg + 1]))
+		  && (!df_regs_ever_live_p (reg + 1)
+		      || call_used_regs[reg + 1]))
 		{
-		  if (start_reg != reg)
+		  if (end_reg > reg + 2)
 		    vfp_output_fldmd (f, SP_REGNUM,
-				      (start_reg - FIRST_VFP_REGNUM) / 2,
-				      (reg - start_reg) / 2);
-		  start_reg = reg + 2;
+				      (reg + 2 - FIRST_VFP_REGNUM) / 2,
+				      (end_reg - (reg + 2)) / 2);
+		  end_reg = reg;
 		}
 	    }
-	  if (start_reg != reg)
-	    vfp_output_fldmd (f, SP_REGNUM,
-			      (start_reg - FIRST_VFP_REGNUM) / 2,
-			      (reg - start_reg) / 2);
+	  if (end_reg > reg + 2)
+	    vfp_output_fldmd (f, SP_REGNUM, 0,
+			      (end_reg - (reg + 2)) / 2);
 	}
+
       if (TARGET_IWMMXT)
 	for (reg = FIRST_IWMMXT_REGNUM; reg <= LAST_IWMMXT_REGNUM; reg++)
 	  if (df_regs_ever_live_p (reg) && !call_used_regs[reg])