Re: Patch to gcc/resource.c for PR target/13256, CRIS, SH, reorg,dbr, strict_low_part.

[Hans-Peter Nilsson <hans-peter dot nilsson at axis dot com>]

> Date: Thu, 04 Dec 2003 16:08:40 -0800
> From: Jim Wilson <wilson@specifixinc.com>

> However, I think a simpler solution here is to just drop the MARK_DEST 
> support.  There is no place in the compiler that uses MARK_DEST, so we 
> can get rid of it.  Once we do that, resource.c goes back to what it 
> looked in in gcc-2.95 and earlier.  The strict_low_part case can be 
> deleted, since now the fall through code at the end handles it 
> correctly.  We still need the zero_extract/sign_extract, case, because 
> we need to pass 0 for in_dest for operands 1 and 2, but there is no if 
> statement needed here.  Likewise for the SET_SRC code in the SET case.

Thank you for the review.

Your detailed suggestion made the following patch an obvious
matter, thus committed.  Tested on cris-axis-elf, sh-unknown-elf
and mips-unknown-elf (delay_slot targets) with simulators.
(mips and sh were at LAST_UPDATED "Tue Nov 25 20:39:13 GMT 2003"
in shoddy shape wrt. C++ but nonetheless).

Test-case committed as previously posted (testcases are covered
by port maintainer authority; I just didn't want to XFAIL it
before).

I'd like to put this in the 3.3 branch too.

	PR target/13256
	* resource.h (enum mark_resource_type): Remove member MARK_DEST.
	The only user changed as follows:
	* resource.c (mark_set_resources) <case SET>: Always recurse for
	SET_SRC (x).
	<case SIGN_EXTRACT, case ZERO_EXTRACT>: Always recurse on
	operands.
	<case STRICT_LOW_PART>: Delete, deferring to default code.

Index: resource.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/resource.c,v
retrieving revision 1.63
diff -p -c -r1.63 resource.c
*** resource.c	19 Jul 2003 14:47:13 -0000	1.63
--- resource.c	5 Dec 2003 11:42:53 -0000
*************** find_dead_or_set_registers (rtx target, 
*** 616,622 ****
  /* Given X, a part of an insn, and a pointer to a `struct resource',
     RES, indicate which resources are modified by the insn. If
     MARK_TYPE is MARK_SRC_DEST_CALL, also mark resources potentially
!    set by the called routine.  If MARK_TYPE is MARK_DEST, only mark SET_DESTs
  
     If IN_DEST is nonzero, it means we are inside a SET.  Otherwise,
     objects are being referenced instead of set.
--- 616,622 ----
  /* Given X, a part of an insn, and a pointer to a `struct resource',
     RES, indicate which resources are modified by the insn. If
     MARK_TYPE is MARK_SRC_DEST_CALL, also mark resources potentially
!    set by the called routine.
  
     If IN_DEST is nonzero, it means we are inside a SET.  Otherwise,
     objects are being referenced instead of set.
*************** mark_set_resources (rtx x, struct resour
*** 716,723 ****
  			   || GET_CODE (SET_SRC (x)) != CALL),
  			  mark_type);
  
!       if (mark_type != MARK_DEST)
! 	mark_set_resources (SET_SRC (x), res, 0, MARK_SRC_DEST);
        return;
  
      case CLOBBER:
--- 716,722 ----
  			   || GET_CODE (SET_SRC (x)) != CALL),
  			  mark_type);
  
!       mark_set_resources (SET_SRC (x), res, 0, MARK_SRC_DEST);
        return;
  
      case CLOBBER:
*************** mark_set_resources (rtx x, struct resour
*** 747,758 ****
  
      case SIGN_EXTRACT:
      case ZERO_EXTRACT:
!       if (! (mark_type == MARK_DEST && in_dest))
! 	{
! 	  mark_set_resources (XEXP (x, 0), res, in_dest, MARK_SRC_DEST);
! 	  mark_set_resources (XEXP (x, 1), res, 0, MARK_SRC_DEST);
! 	  mark_set_resources (XEXP (x, 2), res, 0, MARK_SRC_DEST);
! 	}
        return;
  
      case MEM:
--- 746,754 ----
  
      case SIGN_EXTRACT:
      case ZERO_EXTRACT:
!       mark_set_resources (XEXP (x, 0), res, in_dest, MARK_SRC_DEST);
!       mark_set_resources (XEXP (x, 1), res, 0, MARK_SRC_DEST);
!       mark_set_resources (XEXP (x, 2), res, 0, MARK_SRC_DEST);
        return;
  
      case MEM:
*************** mark_set_resources (rtx x, struct resour
*** 798,810 ****
  	    SET_HARD_REG_BIT (res->regs, r);
  	}
        return;
- 
-     case STRICT_LOW_PART:
-       if (! (mark_type == MARK_DEST && in_dest))
- 	{
- 	  mark_set_resources (XEXP (x, 0), res, 0, MARK_SRC_DEST);
- 	  return;
- 	}
  
      case UNSPEC_VOLATILE:
      case ASM_INPUT:
--- 794,799 ----
Index: resource.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/resource.h,v
retrieving revision 1.10
diff -p -c -r1.10 resource.h
*** resource.h	6 Jul 2003 09:56:08 -0000	1.10
--- resource.h	5 Dec 2003 11:42:53 -0000
*************** struct resources
*** 37,44 ****
  enum mark_resource_type
  {
    MARK_SRC_DEST = 0,
!   MARK_SRC_DEST_CALL = 1,
!   MARK_DEST = 2
  };
  
  extern void mark_target_live_regs (rtx, rtx, struct resources *);
--- 37,43 ----
  enum mark_resource_type
  {
    MARK_SRC_DEST = 0,
!   MARK_SRC_DEST_CALL = 1
  };
  
  extern void mark_target_live_regs (rtx, rtx, struct resources *);

brgds, H-P