linux-stable/arch/arm/nwfpe/fpa11_cprt.c
Thomas Gleixner 74ba9207e1 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 441 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:36:45 +02:00

361 lines
8.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
NetWinder Floating Point Emulator
(c) Rebel.COM, 1998,1999
(c) Philip Blundell, 1999, 2001
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
*/
#include "fpa11.h"
#include "fpopcode.h"
#include "fpa11.inl"
#include "fpmodule.h"
#include "fpmodule.inl"
#include "softfloat.h"
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)
{
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:
return PerformFLT(opcode);
break;
case FIX_CODE >> 20:
return PerformFIX(opcode);
break;
case WFS_CODE >> 20:
writeFPSR(readRegister(getRd(opcode)));
break;
case RFS_CODE >> 20:
writeRegister(getRd(opcode), readFPSR());
break;
default:
return 0;
}
return 1;
}
unsigned int PerformFLT(const unsigned int opcode)
{
FPA11 *fpa11 = GET_FPA11();
struct roundingData roundData;
roundData.mode = SetRoundingMode(opcode);
roundData.precision = SetRoundingPrecision(opcode);
roundData.exception = 0;
switch (opcode & MASK_ROUNDING_PRECISION) {
case ROUND_SINGLE:
{
fpa11->fType[getFn(opcode)] = typeSingle;
fpa11->fpreg[getFn(opcode)].fSingle = int32_to_float32(&roundData, readRegister(getRd(opcode)));
}
break;
case ROUND_DOUBLE:
{
fpa11->fType[getFn(opcode)] = typeDouble;
fpa11->fpreg[getFn(opcode)].fDouble = int32_to_float64(readRegister(getRd(opcode)));
}
break;
#ifdef CONFIG_FPE_NWFPE_XP
case ROUND_EXTENDED:
{
fpa11->fType[getFn(opcode)] = typeExtended;
fpa11->fpreg[getFn(opcode)].fExtended = int32_to_floatx80(readRegister(getRd(opcode)));
}
break;
#endif
default:
return 0;
}
if (roundData.exception)
float_raise(roundData.exception);
return 1;
}
unsigned int PerformFIX(const unsigned int opcode)
{
FPA11 *fpa11 = GET_FPA11();
unsigned int Fn = getFm(opcode);
struct roundingData roundData;
roundData.mode = SetRoundingMode(opcode);
roundData.precision = SetRoundingPrecision(opcode);
roundData.exception = 0;
switch (fpa11->fType[Fn]) {
case typeSingle:
{
writeRegister(getRd(opcode), float32_to_int32(&roundData, fpa11->fpreg[Fn].fSingle));
}
break;
case typeDouble:
{
writeRegister(getRd(opcode), float64_to_int32(&roundData, fpa11->fpreg[Fn].fDouble));
}
break;
#ifdef CONFIG_FPE_NWFPE_XP
case typeExtended:
{
writeRegister(getRd(opcode), floatx80_to_int32(&roundData, fpa11->fpreg[Fn].fExtended));
}
break;
#endif
default:
return 0;
}
if (roundData.exception)
float_raise(roundData.exception);
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 = getFn(opcode), Fm = getFm(opcode);
int e_flag = opcode & 0x400000; /* 1 if CxFE */
int n_flag = opcode & 0x200000; /* 1 if CNxx */
unsigned int flags = 0;
#ifdef CONFIG_FPE_NWFPE_XP
floatx80 rFn, rFm;
/* 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);
break;
case typeDouble:
//printk("double.\n");
if (float64_is_nan(fpa11->fpreg[Fn].fDouble))
goto unordered;
rFn = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);
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);
break;
case typeDouble:
//printk("double.\n");
if (float64_is_nan(fpa11->fpreg[Fm].fDouble))
goto unordered;
rFm = float64_to_floatx80(fpa11->fpreg[Fm].fDouble);
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;
/* test for less than condition */
if (floatx80_lt(rFn, rFm))
flags |= CC_NEGATIVE;
/* test for equal condition */
if (floatx80_eq(rFn, rFm))
flags |= CC_ZERO;
/* test for greater than or equal condition */
if (floatx80_lt(rFm, rFn))
flags |= CC_CARRY;
#else
if (CONSTANT_FM(opcode)) {
/* Fm is a constant. Do the comparison in whatever precision
Fn happens to be stored in. */
if (fpa11->fType[Fn] == typeSingle) {
float32 rFm = getSingleConstant(Fm);
float32 rFn = fpa11->fpreg[Fn].fSingle;
if (float32_is_nan(rFn))
goto unordered;
if (n_flag)
rFm ^= 0x80000000;
/* test for less than condition */
if (float32_lt_nocheck(rFn, rFm))
flags |= CC_NEGATIVE;
/* test for equal condition */
if (float32_eq_nocheck(rFn, rFm))
flags |= CC_ZERO;
/* test for greater than or equal condition */
if (float32_lt_nocheck(rFm, rFn))
flags |= CC_CARRY;
} else {
float64 rFm = getDoubleConstant(Fm);
float64 rFn = fpa11->fpreg[Fn].fDouble;
if (float64_is_nan(rFn))
goto unordered;
if (n_flag)
rFm ^= 0x8000000000000000ULL;
/* test for less than condition */
if (float64_lt_nocheck(rFn, rFm))
flags |= CC_NEGATIVE;
/* test for equal condition */
if (float64_eq_nocheck(rFn, rFm))
flags |= CC_ZERO;
/* test for greater than or equal condition */
if (float64_lt_nocheck(rFm, rFn))
flags |= CC_CARRY;
}
} else {
/* Both operands are in registers. */
if (fpa11->fType[Fn] == typeSingle
&& fpa11->fType[Fm] == typeSingle) {
float32 rFm = fpa11->fpreg[Fm].fSingle;
float32 rFn = fpa11->fpreg[Fn].fSingle;
if (float32_is_nan(rFn)
|| float32_is_nan(rFm))
goto unordered;
if (n_flag)
rFm ^= 0x80000000;
/* test for less than condition */
if (float32_lt_nocheck(rFn, rFm))
flags |= CC_NEGATIVE;
/* test for equal condition */
if (float32_eq_nocheck(rFn, rFm))
flags |= CC_ZERO;
/* test for greater than or equal condition */
if (float32_lt_nocheck(rFm, rFn))
flags |= CC_CARRY;
} else {
/* Promote 32-bit operand to 64 bits. */
float64 rFm, rFn;
rFm = (fpa11->fType[Fm] == typeSingle) ?
float32_to_float64(fpa11->fpreg[Fm].fSingle)
: fpa11->fpreg[Fm].fDouble;
rFn = (fpa11->fType[Fn] == typeSingle) ?
float32_to_float64(fpa11->fpreg[Fn].fSingle)
: fpa11->fpreg[Fn].fDouble;
if (float64_is_nan(rFn)
|| float64_is_nan(rFm))
goto unordered;
if (n_flag)
rFm ^= 0x8000000000000000ULL;
/* test for less than condition */
if (float64_lt_nocheck(rFn, rFm))
flags |= CC_NEGATIVE;
/* test for equal condition */
if (float64_eq_nocheck(rFn, rFm))
flags |= CC_ZERO;
/* test for greater than or equal condition */
if (float64_lt_nocheck(rFm, rFn))
flags |= CC_CARRY;
}
}
#endif
writeConditionCodes(flags);
return 1;
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);
writeConditionCodes(flags);
return 1;
}