diff -r bd5e0a849352 -r b150d6f590fc patches/gcc/3.4.6/601-arm-ldm.patch --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/patches/gcc/3.4.6/601-arm-ldm.patch Mon Jul 28 21:08:01 2008 +0000 @@ -0,0 +1,120 @@ +diff -durN gcc-3.4.6.orig/gcc/config/arm/arm.c gcc-3.4.6/gcc/config/arm/arm.c +--- gcc-3.4.6.orig/gcc/config/arm/arm.c 2007-08-15 22:56:20.000000000 +0200 ++++ gcc-3.4.6/gcc/config/arm/arm.c 2007-08-15 22:56:20.000000000 +0200 +@@ -8524,6 +8524,26 @@ + 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 (rtx sibling) + { +@@ -8757,27 +8777,47 @@ + 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) +@@ -11405,22 +11445,6 @@ + } + } + +-/* Return the number (counting from 0) of +- the least significant set bit in MASK. */ +- +-inline static int +-number_of_first_bit_set (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. */