Fix postreload-gcse treatment of call-clobbered registers

[Richard Sandiford <rsandifo@nildram.co.uk>]

This is the patch that inspired the HARD_REG_SET constructs I just posted
(and it depends on them).  postreload-gcse.c was only checking whether
REGNO (x) is call-clobbered, but it should check whether the whole
register is.

I verified that this bug is still present on dataflow-branch.
I tripped over it while doing some other changes, so I don't have
a mainline testcase.  Hopefully the fix is obvious enough not to
need one.

Bootstrapped & regression-tested on x86_64-linux-gnu.  Also
regression-tested on sh-elf (,-m2,-m3,-m4,-m4/-ml) and built
on arm-elf.  OK to install?

Richard


gcc/
	* postreload-gcse.c (reg_set_between_after_reload_p): Check
	whether any part of a multi-register value is call-clobbered.
	(reg_used_between_after_reload_p): Likewise.

Index: gcc/postreload-gcse.c
===================================================================
--- gcc/postreload-gcse.c	2007-05-21 00:23:48.000000000 +0100
+++ gcc/postreload-gcse.c	2007-05-21 00:26:28.000000000 +0100
@@ -880,7 +880,8 @@ reg_set_between_after_reload_p (rtx reg,
 	if (set_of (reg, insn) != NULL_RTX)
 	  return insn;
 	if ((CALL_P (insn)
-	      && call_used_regs[REGNO (reg)])
+	     && overlaps_hard_reg_set_p (call_used_reg_set,
+					 GET_MODE (reg), REGNO (reg)))
 	    || find_reg_fusage (insn, CLOBBER, reg))
 	  return insn;
 
@@ -913,7 +914,8 @@ reg_used_between_after_reload_p (rtx reg
       {
 	if (reg_overlap_mentioned_p (reg, PATTERN (insn))
 	    || (CALL_P (insn)
-		&& call_used_regs[REGNO (reg)])
+		&& overlaps_hard_reg_set_p (call_used_reg_set,
+					    GET_MODE (reg), REGNO (reg)))
 	    || find_reg_fusage (insn, USE, reg)
 	    || find_reg_fusage (insn, CLOBBER, reg))
 	  return insn;