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120 lines
3.3 KiB
Diff
120 lines
3.3 KiB
Diff
--- gcc-3.4.0/gcc/config/arm/arm.c.arm-ldm 2004-02-27 09:51:05.000000000 -0500
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+++ gcc-3.4.0/gcc/config/arm/arm.c 2004-04-24 18:16:25.000000000 -0400
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@@ -8520,6 +8520,26 @@
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return_used_this_function = 0;
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}
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+/* Return the number (counting from 0) of
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+ the least significant set bit in MASK. */
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+
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+#ifdef __GNUC__
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+inline
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+#endif
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+static int
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+number_of_first_bit_set (mask)
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+ int mask;
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+{
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+ int bit;
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+
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+ for (bit = 0;
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+ (mask & (1 << bit)) == 0;
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+ ++bit)
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+ continue;
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+
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+ return bit;
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+}
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+
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const char *
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arm_output_epilogue (rtx sibling)
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{
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@@ -8753,27 +8773,47 @@
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saved_regs_mask |= (1 << PC_REGNUM);
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}
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- /* Load the registers off the stack. If we only have one register
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- to load use the LDR instruction - it is faster. */
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- if (saved_regs_mask == (1 << LR_REGNUM))
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- {
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- /* The exception handler ignores the LR, so we do
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- not really need to load it off the stack. */
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- if (eh_ofs)
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- asm_fprintf (f, "\tadd\t%r, %r, #4\n", SP_REGNUM, SP_REGNUM);
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- else
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- asm_fprintf (f, "\tldr\t%r, [%r], #4\n", LR_REGNUM, SP_REGNUM);
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- }
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- else if (saved_regs_mask)
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+ if (saved_regs_mask)
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{
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- if (saved_regs_mask & (1 << SP_REGNUM))
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- /* Note - write back to the stack register is not enabled
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- (ie "ldmfd sp!..."). We know that the stack pointer is
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- in the list of registers and if we add writeback the
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- instruction becomes UNPREDICTABLE. */
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- print_multi_reg (f, "ldmfd\t%r", SP_REGNUM, saved_regs_mask);
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+ /* Load the registers off the stack. If we only have one register
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+ to load use the LDR instruction - it is faster. */
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+ if (bit_count (saved_regs_mask) == 1)
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+ {
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+ int reg = number_of_first_bit_set (saved_regs_mask);
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+
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+ switch (reg)
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+ {
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+ case SP_REGNUM:
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+ /* Mustn't use base writeback when loading SP. */
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+ asm_fprintf (f, "\tldr\t%r, [%r]\n", SP_REGNUM, SP_REGNUM);
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+ break;
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+
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+ case LR_REGNUM:
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+ if (eh_ofs)
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+ {
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+ /* The exception handler ignores the LR, so we do
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+ not really need to load it off the stack. */
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+ asm_fprintf (f, "\tadd\t%r, %r, #4\n", SP_REGNUM, SP_REGNUM);
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+ break;
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+ }
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+ /* else fall through */
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+
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+ default:
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+ asm_fprintf (f, "\tldr\t%r, [%r], #4\n", reg, SP_REGNUM);
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+ break;
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+ }
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+ }
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else
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- print_multi_reg (f, "ldmfd\t%r!", SP_REGNUM, saved_regs_mask);
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+ {
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+ if (saved_regs_mask & (1 << SP_REGNUM))
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+ /* Note - write back to the stack register is not enabled
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+ (ie "ldmfd sp!..."). We know that the stack pointer is
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+ in the list of registers and if we add writeback the
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+ instruction becomes UNPREDICTABLE. */
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+ print_multi_reg (f, "ldmfd\t%r", SP_REGNUM, saved_regs_mask);
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+ else
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+ print_multi_reg (f, "ldmfd\t%r!", SP_REGNUM, saved_regs_mask);
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+ }
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}
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if (current_function_pretend_args_size)
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@@ -11401,22 +11441,6 @@
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}
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}
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-/* Return the number (counting from 0) of
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- the least significant set bit in MASK. */
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-
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-inline static int
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-number_of_first_bit_set (int mask)
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-{
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- int bit;
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-
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- for (bit = 0;
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- (mask & (1 << bit)) == 0;
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- ++bit)
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- continue;
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-
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- return bit;
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-}
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-
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/* Generate code to return from a thumb function.
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If 'reg_containing_return_addr' is -1, then the return address is
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actually on the stack, at the stack pointer. */
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