From 39221a82be8d224e935bdba10ce108a1a808a52f Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Fri, 9 Apr 2010 20:52:48 +0200 Subject: [PATCH] tcg/arm: remove SAVE_LR code There is no need to save the LR register (r14) before a call to a subroutine. According to the "Procedure Call Standard for the ARM Architecture", it is the job of the callee to save this register. Moreover, this register is already saved in the prologue/epilogue. This patch removes the disabled SAVE_LR code, as there is no need to reenable later. Signed-off-by: Aurelien Jarno --- tcg/arm/tcg-target.c | 43 ------------------------------------------- 1 file changed, 43 deletions(-) diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c index f0f669d..e86ed9a 100644 --- a/tcg/arm/tcg-target.c +++ b/tcg/arm/tcg-target.c @@ -748,10 +748,6 @@ static inline void tcg_out_call(TCGContext *s, int cond, uint32_t addr) { int32_t val; -#ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, TCG_REG_R8, 0, 14, SHIFT_IMM_LSL(0)); -#endif - val = addr - (tcg_target_long) s->code_ptr; if (val < 0x01fffffd && val > -0x01fffffd) tcg_out_bl(s, cond, val); @@ -770,23 +766,13 @@ static inline void tcg_out_call(TCGContext *s, int cond, uint32_t addr) } #endif } - -#ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 14, 0, TCG_REG_R8, SHIFT_IMM_LSL(0)); -#endif } static inline void tcg_out_callr(TCGContext *s, int cond, int arg) { -#ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, TCG_REG_R8, 0, 14, SHIFT_IMM_LSL(0)); -#endif /* TODO: on ARMv5 and ARMv6 replace with tcg_out_blx(s, cond, arg); */ tcg_out_dat_reg(s, cond, ARITH_MOV, 14, 0, 15, SHIFT_IMM_LSL(0)); tcg_out_bx(s, cond, arg); -#ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 14, 0, TCG_REG_R8, SHIFT_IMM_LSL(0)); -#endif } static inline void tcg_out_goto_label(TCGContext *s, int cond, int label_index) @@ -922,10 +908,6 @@ static inline void tcg_out_qemu_ld(TCGContext *s, int cond, label_ptr = (void *) s->code_ptr; tcg_out_b(s, COND_EQ, 8); -# ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 8, 0, 14, SHIFT_IMM_LSL(0)); -# endif - /* TODO: move this code to where the constants pool will be */ if (addr_reg) tcg_out_dat_reg(s, cond, ARITH_MOV, @@ -972,10 +954,6 @@ static inline void tcg_out_qemu_ld(TCGContext *s, int cond, break; } -# ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 14, 0, 8, SHIFT_IMM_LSL(0)); -# endif - *label_ptr += ((void *) s->code_ptr - (void *) label_ptr - 8) >> 2; #else /* !CONFIG_SOFTMMU */ if (GUEST_BASE) { @@ -1186,10 +1164,6 @@ static inline void tcg_out_qemu_st(TCGContext *s, int cond, } # endif -# ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 8, 0, 14, SHIFT_IMM_LSL(0)); -# endif - tcg_out_bl(s, cond, (tcg_target_long) qemu_st_helpers[s_bits] - (tcg_target_long) s->code_ptr); # if TARGET_LONG_BITS == 64 @@ -1197,10 +1171,6 @@ static inline void tcg_out_qemu_st(TCGContext *s, int cond, tcg_out_dat_imm(s, cond, ARITH_ADD, 13, 13, 0x10); # endif -# ifdef SAVE_LR - tcg_out_dat_reg(s, cond, ARITH_MOV, 14, 0, 8, SHIFT_IMM_LSL(0)); -# endif - *label_ptr += ((void *) s->code_ptr - (void *) label_ptr - 8) >> 2; #else /* !CONFIG_SOFTMMU */ if (GUEST_BASE) { @@ -1254,15 +1224,6 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, switch (opc) { case INDEX_op_exit_tb: -#ifdef SAVE_LR - if (args[0] >> 8) - tcg_out_ld32_12(s, COND_AL, TCG_REG_R0, 15, 0); - else - tcg_out_dat_imm(s, COND_AL, ARITH_MOV, TCG_REG_R0, 0, args[0]); - tcg_out_dat_reg(s, COND_AL, ARITH_MOV, 15, 0, 14, SHIFT_IMM_LSL(0)); - if (args[0] >> 8) - tcg_out32(s, args[0]); -#else { uint8_t *ld_ptr = s->code_ptr; if (args[0] >> 8) @@ -1275,7 +1236,6 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out32(s, args[0]); } } -#endif break; case INDEX_op_goto_tb: if (s->tb_jmp_offset) { @@ -1627,9 +1587,6 @@ void tcg_target_init(TCGContext *s) (1 << TCG_REG_R12) | (1 << TCG_REG_R14)); tcg_regset_clear(s->reserved_regs); -#ifdef SAVE_LR - tcg_regset_set_reg(s->reserved_regs, TCG_REG_R14); -#endif tcg_regset_set_reg(s->reserved_regs, TCG_REG_CALL_STACK); tcg_regset_set_reg(s->reserved_regs, TCG_REG_R8); -- 2.7.4