diff options
Diffstat (limited to 'gcc/config/m68k/m68k.c')
| -rw-r--r-- | gcc/config/m68k/m68k.c | 126 |
1 files changed, 125 insertions, 1 deletions
diff --git a/gcc/config/m68k/m68k.c b/gcc/config/m68k/m68k.c index c7e0e5cdfad..cb94d232923 100644 --- a/gcc/config/m68k/m68k.c +++ b/gcc/config/m68k/m68k.c @@ -73,6 +73,8 @@ static void m68k_hp320_internal_label PARAMS ((FILE *, const char *, unsigned lo static void m68k_output_mi_thunk PARAMS ((FILE *, tree, HOST_WIDE_INT, HOST_WIDE_INT, tree)); static int m68k_save_reg PARAMS ((unsigned int)); +static int const_int_cost PARAMS ((rtx)); +static bool m68k_rtx_costs PARAMS ((rtx, int, int, int *)); /* Alignment to use for loops and jumps */ @@ -139,6 +141,9 @@ int m68k_last_compare_had_fp_operands; #undef TARGET_ASM_CAN_OUTPUT_MI_THUNK #define TARGET_ASM_CAN_OUTPUT_MI_THUNK default_can_output_mi_thunk_no_vcall +#undef TARGET_RTX_COSTS +#define TARGET_RTX_COSTS m68k_rtx_costs + struct gcc_target targetm = TARGET_INITIALIZER; /* Sometimes certain combinations of command options do not make @@ -1708,7 +1713,7 @@ const_method (constant) return MOVL; } -int +static int const_int_cost (constant) rtx constant; { @@ -1730,6 +1735,125 @@ const_int_cost (constant) } } +static bool +m68k_rtx_costs (x, code, outer_code, total) + rtx x; + int code, outer_code; + int *total; +{ + switch (code) + { + case CONST_INT: + /* Constant zero is super cheap due to clr instruction. */ + if (x == const0_rtx) + *total = 0; + else + *total = const_int_cost (x); + return true; + + case CONST: + case LABEL_REF: + case SYMBOL_REF: + *total = 3; + return true; + + case CONST_DOUBLE: + /* Make 0.0 cheaper than other floating constants to + encourage creating tstsf and tstdf insns. */ + if (outer_code == COMPARE + && (x == CONST0_RTX (SFmode) || x == CONST0_RTX (DFmode))) + *total = 4; + else + *total = 5; + return true; + + /* These are vaguely right for a 68020. */ + /* The costs for long multiply have been adjusted to work properly + in synth_mult on the 68020, relative to an average of the time + for add and the time for shift, taking away a little more because + sometimes move insns are needed. */ + /* div?.w is relatively cheaper on 68000 counted in COSTS_N_INSNS terms. */ +#define MULL_COST (TARGET_68060 ? 2 : TARGET_68040 ? 5 : 13) +#define MULW_COST (TARGET_68060 ? 2 : TARGET_68040 ? 3 : TARGET_68020 ? 8 : 5) +#define DIVW_COST (TARGET_68020 ? 27 : 12) + + case PLUS: + /* An lea costs about three times as much as a simple add. */ + if (GET_MODE (x) == SImode + && GET_CODE (XEXP (x, 1)) == REG + && GET_CODE (XEXP (x, 0)) == MULT + && GET_CODE (XEXP (XEXP (x, 0), 0)) == REG + && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT + && (INTVAL (XEXP (XEXP (x, 0), 1)) == 2 + || INTVAL (XEXP (XEXP (x, 0), 1)) == 4 + || INTVAL (XEXP (XEXP (x, 0), 1)) == 8)) + *total = COSTS_N_INSNS (3); /* lea an@(dx:l:i),am */ + return false; + + case ASHIFT: + case ASHIFTRT: + case LSHIFTRT: + if (TARGET_68060) + { + *total = COSTS_N_INSNS(1); + return true; + } + if (! TARGET_68020) + { + if (GET_CODE (XEXP (x, 1)) == CONST_INT) + { + if (INTVAL (XEXP (x, 1)) < 16) + *total = COSTS_N_INSNS (2) + INTVAL (XEXP (x, 1)) / 2; + else + /* We're using clrw + swap for these cases. */ + *total = COSTS_N_INSNS (4) + (INTVAL (XEXP (x, 1)) - 16) / 2; + } + else + *total = COSTS_N_INSNS (10); /* worst case */ + return true; + } + /* A shift by a big integer takes an extra instruction. */ + if (GET_CODE (XEXP (x, 1)) == CONST_INT + && (INTVAL (XEXP (x, 1)) == 16)) + { + *total = COSTS_N_INSNS (2); /* clrw;swap */ + return true; + } + if (GET_CODE (XEXP (x, 1)) == CONST_INT + && !(INTVAL (XEXP (x, 1)) > 0 + && INTVAL (XEXP (x, 1)) <= 8)) + { + *total = COSTS_N_INSNS (3); /* lsr #i,dn */ + return true; + } + return false; + + case MULT: + if ((GET_CODE (XEXP (x, 0)) == ZERO_EXTEND + || GET_CODE (XEXP (x, 0)) == SIGN_EXTEND) + && GET_MODE (x) == SImode) + *total = COSTS_N_INSNS (MULW_COST); + else if (GET_MODE (x) == QImode || GET_MODE (x) == HImode) + *total = COSTS_N_INSNS (MULW_COST); + else + *total = COSTS_N_INSNS (MULL_COST); + return true; + + case DIV: + case UDIV: + case MOD: + case UMOD: + if (GET_MODE (x) == QImode || GET_MODE (x) == HImode) + *total = COSTS_N_INSNS (DIVW_COST); /* div.w */ + else + *total = COSTS_N_INSNS (43); /* div.l */ + return true; + + default: + return false; + } +} + const char * output_move_const_into_data_reg (operands) rtx *operands; |