patches/gcc/3.4.6/600-gcc34-arm-ldm-peephole.patch
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Wed May 21 22:00:52 2008 +0000 (2008-05-21)
changeset 527 4ac12179ef23
permissions -rw-r--r--
Introduce target-specific LDFLAGS, the same way we have CFLAGS for the target.
It seems to be helping gcc somewhat into telling the correct endianness to ld that sticks with little endian even when the target is big (eg armeb-unknown-linux-uclibcgnueabi).
There's still work to do, especially finish the gcc part that is not in this commit.

/trunk/scripts/functions | 9 7 2 0 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
     1 diff -durN gcc-3.4.6.orig/gcc/config/arm/arm.c gcc-3.4.6/gcc/config/arm/arm.c
     2 --- gcc-3.4.6.orig/gcc/config/arm/arm.c	2005-10-01 15:31:38.000000000 +0200
     3 +++ gcc-3.4.6/gcc/config/arm/arm.c	2007-08-15 22:54:59.000000000 +0200
     4 @@ -4857,6 +4857,11 @@
     5        *load_offset = unsorted_offsets[order[0]];
     6      }
     7  
     8 +  /* For XScale a two-word LDM is a performance loss, so only do this if
     9 +     size is more important.  See comments in arm_gen_load_multiple.  */
    10 +  if (nops == 2 && arm_tune_xscale && !optimize_size)
    11 +    return 0;
    12 +
    13    if (unsorted_offsets[order[0]] == 0)
    14      return 1; /* ldmia */
    15  
    16 @@ -5083,6 +5088,11 @@
    17        *load_offset = unsorted_offsets[order[0]];
    18      }
    19  
    20 +  /* For XScale a two-word LDM is a performance loss, so only do this if
    21 +     size is more important.  See comments in arm_gen_load_multiple.  */
    22 +  if (nops == 2 && arm_tune_xscale && !optimize_size)
    23 +    return 0;
    24 +
    25    if (unsorted_offsets[order[0]] == 0)
    26      return 1; /* stmia */
    27  
    28 diff -durN gcc-3.4.6.orig/gcc/config/arm/arm.md gcc-3.4.6/gcc/config/arm/arm.md
    29 --- gcc-3.4.6.orig/gcc/config/arm/arm.md	2005-10-01 15:31:38.000000000 +0200
    30 +++ gcc-3.4.6/gcc/config/arm/arm.md	2007-08-15 22:54:59.000000000 +0200
    31 @@ -8811,13 +8811,16 @@
    32     (set_attr "length" "4,8,8")]
    33  )
    34  
    35 +; Try to convert LDR+LDR+arith into [add+]LDM+arith
    36 +; On XScale, LDM is always slower than two LDRs, so only do this if
    37 +; optimising for size.
    38  (define_insn "*arith_adjacentmem"
    39    [(set (match_operand:SI 0 "s_register_operand" "=r")
    40  	(match_operator:SI 1 "shiftable_operator"
    41  	 [(match_operand:SI 2 "memory_operand" "m")
    42  	  (match_operand:SI 3 "memory_operand" "m")]))
    43     (clobber (match_scratch:SI 4 "=r"))]
    44 -  "TARGET_ARM && adjacent_mem_locations (operands[2], operands[3])"
    45 +  "TARGET_ARM && (!arm_tune_xscale || optimize_size) && adjacent_mem_locations (operands[2], operands[3])"
    46    "*
    47    {
    48      rtx ldm[3];
    49 @@ -8852,6 +8855,8 @@
    50        }
    51     if (val1 && val2)
    52        {
    53 +	/* This would be a loss on a Harvard core, but adjacent_mem_locations()
    54 +	   will prevent it from happening.  */
    55  	rtx ops[3];
    56  	ldm[0] = ops[0] = operands[4];
    57  	ops[1] = XEXP (XEXP (operands[2], 0), 0);
    58 diff -durN gcc-3.4.6.orig/gcc/genpeep.c gcc-3.4.6/gcc/genpeep.c
    59 --- gcc-3.4.6.orig/gcc/genpeep.c	2003-07-05 07:27:22.000000000 +0200
    60 +++ gcc-3.4.6/gcc/genpeep.c	2007-08-15 22:54:59.000000000 +0200
    61 @@ -381,6 +381,7 @@
    62    printf ("#include \"recog.h\"\n");
    63    printf ("#include \"except.h\"\n\n");
    64    printf ("#include \"function.h\"\n\n");
    65 +  printf ("#include \"flags.h\"\n\n");
    66  
    67    printf ("#ifdef HAVE_peephole\n");
    68    printf ("extern rtx peep_operand[];\n\n");