diff options
Diffstat (limited to 'gcc/config/arm/arm.c')
| -rw-r--r-- | gcc/config/arm/arm.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 649fde3..95fe7fe 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -4815,6 +4815,15 @@ arm_coproc_mem_operand (rtx op, bool wb) return FALSE; } +/* Return true if X is a register that will be eliminated later on. */ +int +arm_eliminable_register (rtx x) +{ + return REG_P (x) && (REGNO (x) == FRAME_POINTER_REGNUM + || REGNO (x) == ARG_POINTER_REGNUM + || (REGNO (x) >= FIRST_VIRTUAL_REGISTER + && REGNO (x) <= LAST_VIRTUAL_REGISTER)); +} /* Return GENERAL_REGS if a scratch register required to reload x to/from VFP registers. Otherwise return NO_REGS. */ @@ -5086,24 +5095,25 @@ adjacent_mem_locations (rtx a, rtx b) || (GET_CODE (XEXP (b, 0)) == PLUS && GET_CODE (XEXP (XEXP (b, 0), 1)) == CONST_INT))) { - int val0 = 0, val1 = 0; - int reg0, reg1; + HOST_WIDE_INT val0 = 0, val1 = 0; + rtx reg0, reg1; + int val_diff; if (GET_CODE (XEXP (a, 0)) == PLUS) { - reg0 = REGNO (XEXP (XEXP (a, 0), 0)); + reg0 = XEXP (XEXP (a, 0), 0); val0 = INTVAL (XEXP (XEXP (a, 0), 1)); } else - reg0 = REGNO (XEXP (a, 0)); + reg0 = XEXP (a, 0); if (GET_CODE (XEXP (b, 0)) == PLUS) { - reg1 = REGNO (XEXP (XEXP (b, 0), 0)); + reg1 = XEXP (XEXP (b, 0), 0); val1 = INTVAL (XEXP (XEXP (b, 0), 1)); } else - reg1 = REGNO (XEXP (b, 0)); + reg1 = XEXP (b, 0); /* Don't accept any offset that will require multiple instructions to handle, since this would cause the @@ -5111,8 +5121,16 @@ adjacent_mem_locations (rtx a, rtx b) if (!const_ok_for_op (PLUS, val0) || !const_ok_for_op (PLUS, val1)) return 0; - return (reg0 == reg1) && ((val1 - val0) == 4 || (val0 - val1) == 4); + /* Don't allow an eliminable register: register elimination can make + the offset too large. */ + if (arm_eliminable_register (reg0)) + return 0; + + val_diff = val1 - val0; + return ((REGNO (reg0) == REGNO (reg1)) + && (val_diff == 4 || val_diff == -4)); } + return 0; } |