diff options
author | aurel32 <aurel32@c046a42c-6fe2-441c-8c8c-71466251a162> | 2008-04-09 06:53:01 +0000 |
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committer | aurel32 <aurel32@c046a42c-6fe2-441c-8c8c-71466251a162> | 2008-04-09 06:53:01 +0000 |
commit | 3ebdd11939b83b9fd2f27029cd86c1153e51e3a3 (patch) | |
tree | 5070ab4c1cc2324d79b441824b078f54ed612821 /linux-user/arm/nwfpe/fpa11_cprt.c | |
parent | e771edab0d9aaa7925dc26aec3e0c6eac27f19c3 (diff) |
Move target-arm/nwfpe into linux-user/arm/nwfpe
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4185 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'linux-user/arm/nwfpe/fpa11_cprt.c')
-rw-r--r-- | linux-user/arm/nwfpe/fpa11_cprt.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/linux-user/arm/nwfpe/fpa11_cprt.c b/linux-user/arm/nwfpe/fpa11_cprt.c new file mode 100644 index 0000000000..04eae8c6fc --- /dev/null +++ b/linux-user/arm/nwfpe/fpa11_cprt.c @@ -0,0 +1,286 @@ +/* + NetWinder Floating Point Emulator + (c) Rebel.COM, 1998,1999 + (c) Philip Blundell, 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 "fpa11.inl" +//#include "fpmodule.h" +//#include "fpmodule.inl" + +void SetRoundingMode(const unsigned int opcode); + +unsigned int PerformFLT(const unsigned int opcode); +unsigned int PerformFIX(const unsigned int opcode); + +static unsigned int +PerformComparison(const unsigned int opcode); + +unsigned int EmulateCPRT(const unsigned int opcode) +{ + unsigned int nRc = 1; + + //printk("EmulateCPRT(0x%08x)\n",opcode); + + if (opcode & 0x800000) + { + /* This is some variant of a comparison (PerformComparison will + sort out which one). Since most of the other CPRT + instructions are oddball cases of some sort or other it makes + sense to pull this out into a fast path. */ + return PerformComparison(opcode); + } + + /* Hint to GCC that we'd like a jump table rather than a load of CMPs */ + switch ((opcode & 0x700000) >> 20) + { + case FLT_CODE >> 20: nRc = PerformFLT(opcode); break; + case FIX_CODE >> 20: nRc = PerformFIX(opcode); break; + + case WFS_CODE >> 20: writeFPSR(readRegister(getRd(opcode))); break; + case RFS_CODE >> 20: writeRegister(getRd(opcode),readFPSR()); break; + +#if 0 /* We currently have no use for the FPCR, so there's no point + in emulating it. */ + case WFC_CODE >> 20: writeFPCR(readRegister(getRd(opcode))); + case RFC_CODE >> 20: writeRegister(getRd(opcode),readFPCR()); break; +#endif + + default: nRc = 0; + } + + return nRc; +} + +unsigned int PerformFLT(const unsigned int opcode) +{ + FPA11 *fpa11 = GET_FPA11(); + + unsigned int nRc = 1; + SetRoundingMode(opcode); + + switch (opcode & MASK_ROUNDING_PRECISION) + { + case ROUND_SINGLE: + { + fpa11->fType[getFn(opcode)] = typeSingle; + fpa11->fpreg[getFn(opcode)].fSingle = + int32_to_float32(readRegister(getRd(opcode)), &fpa11->fp_status); + } + break; + + case ROUND_DOUBLE: + { + fpa11->fType[getFn(opcode)] = typeDouble; + fpa11->fpreg[getFn(opcode)].fDouble = + int32_to_float64(readRegister(getRd(opcode)), &fpa11->fp_status); + } + break; + + case ROUND_EXTENDED: + { + fpa11->fType[getFn(opcode)] = typeExtended; + fpa11->fpreg[getFn(opcode)].fExtended = + int32_to_floatx80(readRegister(getRd(opcode)), &fpa11->fp_status); + } + break; + + default: nRc = 0; + } + + return nRc; +} + +unsigned int PerformFIX(const unsigned int opcode) +{ + FPA11 *fpa11 = GET_FPA11(); + unsigned int nRc = 1; + unsigned int Fn = getFm(opcode); + + SetRoundingMode(opcode); + + switch (fpa11->fType[Fn]) + { + case typeSingle: + { + writeRegister(getRd(opcode), + float32_to_int32(fpa11->fpreg[Fn].fSingle, &fpa11->fp_status)); + } + break; + + case typeDouble: + { + //printf("F%d is 0x%" PRIx64 "\n",Fn,fpa11->fpreg[Fn].fDouble); + writeRegister(getRd(opcode), + float64_to_int32(fpa11->fpreg[Fn].fDouble, &fpa11->fp_status)); + } + break; + + case typeExtended: + { + writeRegister(getRd(opcode), + floatx80_to_int32(fpa11->fpreg[Fn].fExtended, &fpa11->fp_status)); + } + break; + + default: nRc = 0; + } + + return nRc; +} + + +static unsigned int __inline__ +PerformComparisonOperation(floatx80 Fn, floatx80 Fm) +{ + FPA11 *fpa11 = GET_FPA11(); + unsigned int flags = 0; + + /* test for less than condition */ + if (floatx80_lt(Fn,Fm, &fpa11->fp_status)) + { + flags |= CC_NEGATIVE; + } + + /* test for equal condition */ + if (floatx80_eq(Fn,Fm, &fpa11->fp_status)) + { + flags |= CC_ZERO; + } + + /* test for greater than or equal condition */ + if (floatx80_lt(Fm,Fn, &fpa11->fp_status)) + { + flags |= CC_CARRY; + } + + writeConditionCodes(flags); + return 1; +} + +/* This instruction sets the flags N, Z, C, V in the FPSR. */ + +static unsigned int PerformComparison(const unsigned int opcode) +{ + FPA11 *fpa11 = GET_FPA11(); + unsigned int Fn, Fm; + floatx80 rFn, rFm; + int e_flag = opcode & 0x400000; /* 1 if CxFE */ + int n_flag = opcode & 0x200000; /* 1 if CNxx */ + unsigned int flags = 0; + + //printk("PerformComparison(0x%08x)\n",opcode); + + Fn = getFn(opcode); + Fm = getFm(opcode); + + /* Check for unordered condition and convert all operands to 80-bit + format. + ?? Might be some mileage in avoiding this conversion if possible. + Eg, if both operands are 32-bit, detect this and do a 32-bit + comparison (cheaper than an 80-bit one). */ + switch (fpa11->fType[Fn]) + { + case typeSingle: + //printk("single.\n"); + if (float32_is_nan(fpa11->fpreg[Fn].fSingle)) + goto unordered; + rFn = float32_to_floatx80(fpa11->fpreg[Fn].fSingle, &fpa11->fp_status); + break; + + case typeDouble: + //printk("double.\n"); + if (float64_is_nan(fpa11->fpreg[Fn].fDouble)) + goto unordered; + rFn = float64_to_floatx80(fpa11->fpreg[Fn].fDouble, &fpa11->fp_status); + break; + + case typeExtended: + //printk("extended.\n"); + if (floatx80_is_nan(fpa11->fpreg[Fn].fExtended)) + goto unordered; + rFn = fpa11->fpreg[Fn].fExtended; + break; + + default: return 0; + } + + if (CONSTANT_FM(opcode)) + { + //printk("Fm is a constant: #%d.\n",Fm); + rFm = getExtendedConstant(Fm); + if (floatx80_is_nan(rFm)) + goto unordered; + } + else + { + //printk("Fm = r%d which contains a ",Fm); + switch (fpa11->fType[Fm]) + { + case typeSingle: + //printk("single.\n"); + if (float32_is_nan(fpa11->fpreg[Fm].fSingle)) + goto unordered; + rFm = float32_to_floatx80(fpa11->fpreg[Fm].fSingle, &fpa11->fp_status); + break; + + case typeDouble: + //printk("double.\n"); + if (float64_is_nan(fpa11->fpreg[Fm].fDouble)) + goto unordered; + rFm = float64_to_floatx80(fpa11->fpreg[Fm].fDouble, &fpa11->fp_status); + break; + + case typeExtended: + //printk("extended.\n"); + if (floatx80_is_nan(fpa11->fpreg[Fm].fExtended)) + goto unordered; + rFm = fpa11->fpreg[Fm].fExtended; + break; + + default: return 0; + } + } + + if (n_flag) + { + rFm.high ^= 0x8000; + } + + return PerformComparisonOperation(rFn,rFm); + + unordered: + /* ?? The FPA data sheet is pretty vague about this, in particular + about whether the non-E comparisons can ever raise exceptions. + This implementation is based on a combination of what it says in + the data sheet, observation of how the Acorn emulator actually + behaves (and how programs expect it to) and guesswork. */ + flags |= CC_OVERFLOW; + flags &= ~(CC_ZERO | CC_NEGATIVE); + + if (BIT_AC & readFPSR()) flags |= CC_CARRY; + + if (e_flag) float_raise(float_flag_invalid, &fpa11->fp_status); + + writeConditionCodes(flags); + return 1; +} |