// -*- mode:c++ -*- // Copyright (c) 2007-2008 The Florida State University // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer; // redistributions in binary form must reproduce the above copyright // notice, this list of conditions and the following disclaimer in the // documentation and/or other materials provided with the distribution; // neither the name of the copyright holders nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // // Authors: Stephen Hines //////////////////////////////////////////////////////////////////// // // Utility functions for execute methods // // output header {{ // Shift types for ARM instructions enum ArmShiftType { LSL = 0, LSR, ASR, ROR }; enum ArmShiftMode { }; inline uint32_t number_of_ones(int32_t val) { uint32_t ones = 0; for (int i = 0; i < 32; i++ ) { if ( val & (1<> 31); } static int32_t arm_POS(int32_t val) { return ((~val) >> 31); } // Shift Rm by an immediate value inline int32_t shift_rm_imm(uint32_t base, uint32_t shamt, uint32_t type, uint32_t cfval) { enum ArmShiftType shiftType; shiftType = (enum ArmShiftType) type; switch (shiftType) { case LSL: return (base << shamt); case LSR: if (shamt == 0) return (0); else return (base >> shamt); case ASR: if (shamt == 0) return ((uint32_t) ((int32_t) base >> 31L)); else return ((uint32_t) (((int32_t) base) >> shamt)); case ROR: //shamt = shamt & 0x1f; if (shamt == 0) return (cfval << 31) | (base >> 1); // RRX else return (base << (32 - shamt)) | (base >> shamt); default: fprintf(stderr, "Unhandled shift type\n"); exit(1); break; } return 0; } // Shift Rm by Rs inline int32_t shift_rm_rs(uint32_t base, uint32_t shamt, uint32_t type, uint32_t cfval) { enum ArmShiftType shiftType; shiftType = (enum ArmShiftType) type; switch (shiftType) { case LSL: if (shamt == 0) return (base); else if (shamt >= 32) return (0); else return (base << shamt); case LSR: if (shamt == 0) return (base); else if (shamt >= 32) return (0); else return (base >> shamt); case ASR: if (shamt == 0) return base; else if (shamt >= 32) return ((uint32_t) ((int32_t) base >> 31L)); else return ((uint32_t) (((int32_t) base) >> (int) shamt)); case ROR: shamt = shamt & 0x1f; if (shamt == 0) return (base); else return ((base << (32 - shamt)) | (base >> shamt)); default: fprintf(stderr, "Unhandled shift type\n"); exit(1); break; } return 0; } // Generate C for a shift by immediate inline int32_t shift_carry_imm(uint32_t base, uint32_t shamt, uint32_t type, uint32_t cfval) { enum ArmShiftType shiftType; shiftType = (enum ArmShiftType) type; switch (shiftType) { case LSL: return (base >> (32 - shamt)) & 1; case LSR: if (shamt == 0) return (base >> 31) & 1; else return (base >> (shamt - 1)) & 1; case ASR: if (shamt == 0) return (base >> 31L); else return ((uint32_t) (((int32_t) base) >> (shamt - 1))) & 1; case ROR: shamt = shamt & 0x1f; if (shamt == 0) return (base & 1); // RRX else return (base >> (shamt - 1)) & 1; default: fprintf(stderr, "Unhandled shift type\n"); exit(1); break; } return 0; } // Generate C for a shift by Rs inline int32_t shift_carry_rs(uint32_t base, uint32_t shamt, uint32_t type, uint32_t cfval) { enum ArmShiftType shiftType; shiftType = (enum ArmShiftType) type; switch (shiftType) { case LSL: if (shamt == 0) return (!!cfval); else if (shamt == 32) return (base & 1); else if (shamt > 32) return (0); else return ((base >> (32 - shamt)) & 1); case LSR: if (shamt == 0) return (!!cfval); else if (shamt == 32) return (base >> 31); else if (shamt > 32) return (0); else return ((base >> (shamt - 1)) & 1); case ASR: if (shamt == 0) return (!!cfval); else if (shamt >= 32) return (base >> 31L); else return (((uint32_t) (((int32_t) base) >> (shamt - 1))) & 1); case ROR: if (shamt == 0) return (!!cfval); shamt = shamt & 0x1f; if (shamt == 0) return (base >> 31); // RRX else return ((base >> (shamt - 1)) & 1); default: fprintf(stderr, "Unhandled shift type\n"); exit(1); break; } return 0; } // Generate the appropriate carry bit for an addition operation inline int32_t arm_add_carry(int32_t result, int32_t lhs, int32_t rhs) { if ((lhs | rhs) >> 30) return ((arm_NEG(lhs) && arm_NEG(rhs)) || (arm_NEG(lhs) && arm_POS(result)) || (arm_NEG(rhs) && arm_POS(result))); else return 0; } // Generate the appropriate carry bit for a subtraction operation inline int32_t arm_sub_carry(int32_t result, int32_t lhs, int32_t rhs) { if ((lhs >= rhs) || ((rhs | lhs) >> 31)) return ((arm_NEG(lhs) && arm_POS(rhs)) || (arm_NEG(lhs) && arm_POS(result)) || (arm_POS(rhs) && arm_POS(result))); else return 0; } inline int32_t arm_add_overflow(int32_t result, int32_t lhs, int32_t rhs) { if ((lhs | rhs) >> 30) return ((arm_NEG(lhs) && arm_NEG(rhs) && arm_POS(result)) || (arm_POS(lhs) && arm_POS(rhs) && arm_NEG(result))); else return 0; } inline int32_t arm_sub_overflow(int32_t result, int32_t lhs, int32_t rhs) { if ((lhs >= rhs) || ((rhs | lhs) >> 31)) return ((arm_NEG(lhs) && arm_POS(rhs) && arm_POS(result)) || (arm_POS(lhs) && arm_NEG(rhs) && arm_NEG(result))); else return 0; } }};