patches/gcc/3.4.6/600-gcc34-arm-ldm-peephole.patch
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Sun Feb 17 22:08:06 2008 +0000 (2008-02-17)
changeset 431 8bde4c6ea47a
permissions -rw-r--r--
Robert P. J. DAY says:

apparently, the patchset for gcc 4.2.1 applies properly to the
source for gcc 4.2.2 and gcc 4.2.3. so, if you want, you can simply
add support for those last two just by augmenting menuconfig and
adding a couple symlinks for those two directories. seems like a
cheap way to add a couple new versions.
     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");