1 files changed, 148 insertions, 0 deletions

diff --git a/meta/packages/gcc/gcc-3.3.4/arm-ldm.dpatch b/meta/packages/gcc/gcc-3.3.4/arm-ldm.dpatch
new file mode 100644
index 0000000000..561624f39c
--- /dev/null
+++ b/meta/packages/gcc/gcc-3.3.4/arm-ldm.dpatch
@@ -0,0 +1,148 @@
+#! /bin/sh -e
+
+src=gcc
+if [ $# -eq 3 -a "$2" = '-d' ]; then
+    pdir="-d $3"
+    src=$3/gcc
+elif [ $# -ne 1 ]; then
+    echo >&2 "`basename $0`: script expects -patch|-unpatch as argument"
+    exit 1
+fi
+case "$1" in
+    -patch)
+        patch $pdir -f --no-backup-if-mismatch -p0 --fuzz 10 < $0
+        ;;
+    -unpatch)
+        patch $pdir -f --no-backup-if-mismatch -R -p0 --fuzz 10 < $0
+        ;;
+    *)
+        echo >&2 "`basename $0`: script expects -patch|-unpatch as argument"
+        exit 1
+esac
+exit 0
+
+# DP: try harder to avoid ldm in function epilogues
+
+--- gcc/config/arm/arm.c        Fri Mar  5 18:49:42 2004
++++ gcc/config/arm/arm.c        Fri Mar  5 16:00:21 2004
+@@ -7598,6 +7629,26 @@
+   return_used_this_function = 0;  
+ }
+ 
++/* Return the number (counting from 0) of
++   the least significant set bit in MASK.  */
++
++#ifdef __GNUC__
++inline
++#endif
++static int
++number_of_first_bit_set (mask)
++     int mask;
++{
++  int bit;
++
++  for (bit = 0;
++       (mask & (1 << bit)) == 0;
++       ++bit)
++    continue;
++
++  return bit;
++}
++
+ const char *
+ arm_output_epilogue (really_return)
+      int really_return;
+@@ -7788,27 +7839,47 @@
+          saved_regs_mask |=   (1 << PC_REGNUM);
+        }
+ 
+-      /* Load the registers off the stack.  If we only have one register
+-        to load use the LDR instruction - it is faster.  */
+-      if (saved_regs_mask == (1 << LR_REGNUM))
+-       {
+-         /* The exception handler ignores the LR, so we do
+-            not really need to load it off the stack.  */
+-         if (eh_ofs)
+-           asm_fprintf (f, "\tadd\t%r, %r, #4\n", SP_REGNUM, SP_REGNUM);
+-         else
+-           asm_fprintf (f, "\tldr\t%r, [%r], #4\n", LR_REGNUM, SP_REGNUM);
+-       }
+-      else if (saved_regs_mask)
++      if (saved_regs_mask)
+        {
+-         if (saved_regs_mask & (1 << SP_REGNUM))
+-           /* Note - write back to the stack register is not enabled
+-              (ie "ldmfd sp!...").  We know that the stack pointer is
+-              in the list of registers and if we add writeback the
+-              instruction becomes UNPREDICTABLE.  */
+-           print_multi_reg (f, "ldmfd\t%r", SP_REGNUM, saved_regs_mask);
++         /* Load the registers off the stack.  If we only have one register
++            to load use the LDR instruction - it is faster.  */
++         if (bit_count (saved_regs_mask) == 1)
++           {
++             int reg = number_of_first_bit_set (saved_regs_mask);
++
++             switch (reg)
++               {
++               case SP_REGNUM:
++                 /* Mustn't use base writeback when loading SP.  */
++                 asm_fprintf (f, "\tldr\t%r, [%r]\n", SP_REGNUM, SP_REGNUM);
++                 break;
++                 
++               case LR_REGNUM:
++                 if (eh_ofs)
++                   {
++                     /* The exception handler ignores the LR, so we do
++                        not really need to load it off the stack.  */
++                     asm_fprintf (f, "\tadd\t%r, %r, #4\n", SP_REGNUM, SP_REGNUM);
++                     break;
++                   }
++                 /* else fall through */
++                 
++               default:
++                 asm_fprintf (f, "\tldr\t%r, [%r], #4\n", reg, SP_REGNUM);
++                 break;
++               }
++           }
+          else
+-           print_multi_reg (f, "ldmfd\t%r!", SP_REGNUM, saved_regs_mask);
++           {
++             if (saved_regs_mask & (1 << SP_REGNUM))
++               /* Note - write back to the stack register is not enabled
++                  (ie "ldmfd sp!...").  We know that the stack pointer is
++                  in the list of registers and if we add writeback the
++                  instruction becomes UNPREDICTABLE.  */
++               print_multi_reg (f, "ldmfd\t%r", SP_REGNUM, saved_regs_mask);
++             else
++               print_multi_reg (f, "ldmfd\t%r!", SP_REGNUM, saved_regs_mask);
++           }
+        }
+ 
+       if (current_function_pretend_args_size)
+@@ -9610,26 +9677,6 @@
+     }
+ }
+ 
+-/* Return the number (counting from 0) of
+-   the least significant set bit in MASK.  */
+-
+-#ifdef __GNUC__
+-inline
+-#endif
+-static int
+-number_of_first_bit_set (mask)
+-     int mask;
+-{
+-  int bit;
+-
+-  for (bit = 0;
+-       (mask & (1 << bit)) == 0;
+-       ++bit)
+-    continue;
+-
+-  return bit;
+-}
+-
+ /* Generate code to return from a thumb function.
+    If 'reg_containing_return_addr' is -1, then the return address is
+    actually on the stack, at the stack pointer.  */