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#! /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. */
|
