diff options
Diffstat (limited to 'arch/arm26/nwfpe/fpopcode.c')
| -rw-r--r-- | arch/arm26/nwfpe/fpopcode.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/arch/arm26/nwfpe/fpopcode.c b/arch/arm26/nwfpe/fpopcode.c new file mode 100644 index 0000000..d81ddd1 --- /dev/null +++ b/arch/arm26/nwfpe/fpopcode.c @@ -0,0 +1,148 @@ +/* + NetWinder Floating Point Emulator + (c) Rebel.COM, 1998,1999 + + Direct questions, comments to Scott Bambrough <scottb@netwinder.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, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include "fpa11.h" +#include "softfloat.h" +#include "fpopcode.h" +#include "fpsr.h" +#include "fpmodule.h" +#include "fpmodule.inl" + +const floatx80 floatx80Constant[] = { + { 0x0000, 0x0000000000000000ULL}, /* extended 0.0 */ + { 0x3fff, 0x8000000000000000ULL}, /* extended 1.0 */ + { 0x4000, 0x8000000000000000ULL}, /* extended 2.0 */ + { 0x4000, 0xc000000000000000ULL}, /* extended 3.0 */ + { 0x4001, 0x8000000000000000ULL}, /* extended 4.0 */ + { 0x4001, 0xa000000000000000ULL}, /* extended 5.0 */ + { 0x3ffe, 0x8000000000000000ULL}, /* extended 0.5 */ + { 0x4002, 0xa000000000000000ULL} /* extended 10.0 */ +}; + +const float64 float64Constant[] = { + 0x0000000000000000ULL, /* double 0.0 */ + 0x3ff0000000000000ULL, /* double 1.0 */ + 0x4000000000000000ULL, /* double 2.0 */ + 0x4008000000000000ULL, /* double 3.0 */ + 0x4010000000000000ULL, /* double 4.0 */ + 0x4014000000000000ULL, /* double 5.0 */ + 0x3fe0000000000000ULL, /* double 0.5 */ + 0x4024000000000000ULL /* double 10.0 */ +}; + +const float32 float32Constant[] = { + 0x00000000, /* single 0.0 */ + 0x3f800000, /* single 1.0 */ + 0x40000000, /* single 2.0 */ + 0x40400000, /* single 3.0 */ + 0x40800000, /* single 4.0 */ + 0x40a00000, /* single 5.0 */ + 0x3f000000, /* single 0.5 */ + 0x41200000 /* single 10.0 */ +}; + +unsigned int getTransferLength(const unsigned int opcode) +{ + unsigned int nRc; + + switch (opcode & MASK_TRANSFER_LENGTH) + { + case 0x00000000: nRc = 1; break; /* single precision */ + case 0x00008000: nRc = 2; break; /* double precision */ + case 0x00400000: nRc = 3; break; /* extended precision */ + default: nRc = 0; + } + + return(nRc); +} + +unsigned int getRegisterCount(const unsigned int opcode) +{ + unsigned int nRc; + + switch (opcode & MASK_REGISTER_COUNT) + { + case 0x00000000: nRc = 4; break; + case 0x00008000: nRc = 1; break; + case 0x00400000: nRc = 2; break; + case 0x00408000: nRc = 3; break; + default: nRc = 0; + } + + return(nRc); +} + +unsigned int getRoundingPrecision(const unsigned int opcode) +{ + unsigned int nRc; + + switch (opcode & MASK_ROUNDING_PRECISION) + { + case 0x00000000: nRc = 1; break; + case 0x00000080: nRc = 2; break; + case 0x00080000: nRc = 3; break; + default: nRc = 0; + } + + return(nRc); +} + +unsigned int getDestinationSize(const unsigned int opcode) +{ + unsigned int nRc; + + switch (opcode & MASK_DESTINATION_SIZE) + { + case 0x00000000: nRc = typeSingle; break; + case 0x00000080: nRc = typeDouble; break; + case 0x00080000: nRc = typeExtended; break; + default: nRc = typeNone; + } + + return(nRc); +} + +/* condition code lookup table + index into the table is test code: EQ, NE, ... LT, GT, AL, NV + bit position in short is condition code: NZCV */ +static const unsigned short aCC[16] = { + 0xF0F0, // EQ == Z set + 0x0F0F, // NE + 0xCCCC, // CS == C set + 0x3333, // CC + 0xFF00, // MI == N set + 0x00FF, // PL + 0xAAAA, // VS == V set + 0x5555, // VC + 0x0C0C, // HI == C set && Z clear + 0xF3F3, // LS == C clear || Z set + 0xAA55, // GE == (N==V) + 0x55AA, // LT == (N!=V) + 0x0A05, // GT == (!Z && (N==V)) + 0xF5FA, // LE == (Z || (N!=V)) + 0xFFFF, // AL always + 0 // NV +}; + +unsigned int checkCondition(const unsigned int opcode, const unsigned int ccodes) +{ + return (aCC[opcode>>28] >> (ccodes>>28)) & 1; +} |
