linux / linux / kernel / git / davem / net-next / refs/tags/v2.6.30-rc2 / . / arch / blackfin / lib / modsi3.S

/* | |

* File: arch/blackfin/lib/modsi3.S | |

* Based on: | |

* Author: | |

* | |

* Created: | |

* Description: This program computes 32 bit signed remainder. It calls div32 function | |

* for quotient estimation. | |

* | |

* Registers used : | |

* Numerator/ Denominator in R0, R1 | |

* R0 - returns remainder. | |

* R2-R7 | |

* | |

* Modified: | |

* Copyright 2004-2006 Analog Devices Inc. | |

* | |

* Bugs: Enter bugs at http://blackfin.uclinux.org/ | |

* | |

* This program is free software; you can redistribute it and/or modify | |

* it under the terms of the GNU General Public License as published by | |

* the Free Software Foundation; either version 2 of the License, or | |

* (at your option) any later version. | |

* | |

* This program is distributed in the hope that it will be useful, | |

* but WITHOUT ANY WARRANTY; without even the implied warranty of | |

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |

* GNU General Public License for more details. | |

* | |

* You should have received a copy of the GNU General Public License | |

* along with this program; if not, see the file COPYING, or write | |

* to the Free Software Foundation, Inc., | |

* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |

*/ | |

.global ___modsi3; | |

.type ___modsi3, STT_FUNC; | |

.extern ___divsi3; | |

.type ___divsi3, STT_FUNC; | |

#ifdef CONFIG_ARITHMETIC_OPS_L1 | |

.section .l1.text | |

#else | |

.text | |

#endif | |

___modsi3: | |

CC=R0==0; | |

IF CC JUMP .LRETURN_R0; /* Return 0, if numerator == 0 */ | |

CC=R1==0; | |

IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == 0 */ | |

CC=R0==R1; | |

IF CC JUMP .LRETURN_ZERO; /* Return 0, if numerator == denominator */ | |

CC = R1 == 1; | |

IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == 1 */ | |

CC = R1 == -1; | |

IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == -1 */ | |

/* Valid input. Use __divsi3() to compute the quotient, and then | |

* derive the remainder from that. */ | |

[--SP] = (R7:6); /* Push R7 and R6 */ | |

[--SP] = RETS; /* and return address */ | |

R7 = R0; /* Copy of R0 */ | |

R6 = R1; /* Save for later */ | |

SP += -12; /* Should always provide this space */ | |

CALL ___divsi3; /* Compute signed quotient using ___divsi3()*/ | |

SP += 12; | |

R0 *= R6; /* Quotient * divisor */ | |

R0 = R7 - R0; /* Dividend - (quotient * divisor) */ | |

RETS = [SP++]; /* Get back return address */ | |

(R7:6) = [SP++]; /* Pop registers R7 and R4 */ | |

RTS; /* Store remainder */ | |

.LRETURN_ZERO: | |

R0 = 0; | |

.LRETURN_R0: | |

RTS; | |

.size ___modsi3, .-___modsi3 |