sh: Support denormalization on SH-4 FPU.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Stuart Menefy 2007-11-30 18:42:27 +09:00 committed by Paul Mundt
parent 453ec9c1c3
commit c8c0a1aba9
4 changed files with 1258 additions and 180 deletions

View file

@ -5,7 +5,7 @@
obj-y := probe.o common.o
common-y += $(addprefix ../sh3/, entry.o ex.o)
obj-$(CONFIG_SH_FPU) += fpu.o
obj-$(CONFIG_SH_FPU) += fpu.o softfloat.o
obj-$(CONFIG_SH_STORE_QUEUES) += sq.o
# CPU subtype setup

View file

@ -1,7 +1,4 @@
/* $Id: fpu.c,v 1.4 2004/01/13 05:52:11 kkojima Exp $
*
* linux/arch/sh/kernel/fpu.c
*
/*
* Save/restore floating point context for signal handlers.
*
* This file is subject to the terms and conditions of the GNU General Public
@ -9,15 +6,16 @@
* for more details.
*
* Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
* Copyright (C) 2006 ST Microelectronics Ltd. (denorm support)
*
* FIXME! These routines can be optimized in big endian case.
* FIXME! These routines have not been tested for big endian case.
*/
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/io.h>
#include <asm/cpu/fpu.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/io.h>
/* The PR (precision) bit in the FP Status Register must be clear when
* an frchg instruction is executed, otherwise the instruction is undefined.
@ -25,20 +23,32 @@
*/
#define FPSCR_RCHG 0x00000000
extern unsigned long long float64_div(unsigned long long a,
unsigned long long b);
extern unsigned long int float32_div(unsigned long int a, unsigned long int b);
extern unsigned long long float64_mul(unsigned long long a,
unsigned long long b);
extern unsigned long int float32_mul(unsigned long int a, unsigned long int b);
extern unsigned long long float64_add(unsigned long long a,
unsigned long long b);
extern unsigned long int float32_add(unsigned long int a, unsigned long int b);
extern unsigned long long float64_sub(unsigned long long a,
unsigned long long b);
extern unsigned long int float32_sub(unsigned long int a, unsigned long int b);
static unsigned int fpu_exception_flags;
/*
* Save FPU registers onto task structure.
* Assume called with FPU enabled (SR.FD=0).
*/
void
save_fpu(struct task_struct *tsk, struct pt_regs *regs)
void save_fpu(struct task_struct *tsk, struct pt_regs *regs)
{
unsigned long dummy;
clear_tsk_thread_flag(tsk, TIF_USEDFPU);
enable_fpu();
asm volatile("sts.l fpul, @-%0\n\t"
asm volatile ("sts.l fpul, @-%0\n\t"
"sts.l fpscr, @-%0\n\t"
"lds %2, fpscr\n\t"
"frchg\n\t"
@ -75,24 +85,21 @@ save_fpu(struct task_struct *tsk, struct pt_regs *regs)
"fmov.s fr2, @-%0\n\t"
"fmov.s fr1, @-%0\n\t"
"fmov.s fr0, @-%0\n\t"
"lds %3, fpscr\n\t"
: "=r" (dummy)
: "0" ((char *)(&tsk->thread.fpu.hard.status)),
"r" (FPSCR_RCHG),
"r" (FPSCR_INIT)
: "memory");
"lds %3, fpscr\n\t":"=r" (dummy)
:"0"((char *)(&tsk->thread.fpu.hard.status)),
"r"(FPSCR_RCHG), "r"(FPSCR_INIT)
:"memory");
disable_fpu();
release_fpu(regs);
}
static void
restore_fpu(struct task_struct *tsk)
static void restore_fpu(struct task_struct *tsk)
{
unsigned long dummy;
enable_fpu();
asm volatile("lds %2, fpscr\n\t"
asm volatile ("lds %2, fpscr\n\t"
"fmov.s @%0+, fr0\n\t"
"fmov.s @%0+, fr1\n\t"
"fmov.s @%0+, fr2\n\t"
@ -129,9 +136,9 @@ restore_fpu(struct task_struct *tsk)
"frchg\n\t"
"lds.l @%0+, fpscr\n\t"
"lds.l @%0+, fpul\n\t"
: "=r" (dummy)
: "0" (&tsk->thread.fpu), "r" (FPSCR_RCHG)
: "memory");
:"=r" (dummy)
:"0"(&tsk->thread.fpu), "r"(FPSCR_RCHG)
:"memory");
disable_fpu();
}
@ -141,11 +148,10 @@ restore_fpu(struct task_struct *tsk)
* double precision represents signaling NANS.
*/
static void
fpu_init(void)
static void fpu_init(void)
{
enable_fpu();
asm volatile("lds %0, fpul\n\t"
asm volatile ( "lds %0, fpul\n\t"
"lds %1, fpscr\n\t"
"fsts fpul, fr0\n\t"
"fsts fpul, fr1\n\t"
@ -183,7 +189,7 @@ fpu_init(void)
"frchg\n\t"
"lds %2, fpscr\n\t"
: /* no output */
: "r" (0), "r" (FPSCR_RCHG), "r" (FPSCR_INIT));
:"r" (0), "r"(FPSCR_RCHG), "r"(FPSCR_INIT));
disable_fpu();
}
@ -194,8 +200,7 @@ fpu_init(void)
* @fpu: Pointer to sh_fpu_hard structure
* @n: Index to FP register
*/
static void
denormal_to_double (struct sh_fpu_hard_struct *fpu, int n)
static void denormal_to_double(struct sh_fpu_hard_struct *fpu, int n)
{
unsigned long du, dl;
unsigned long x = fpu->fpul;
@ -212,7 +217,7 @@ denormal_to_double (struct sh_fpu_hard_struct *fpu, int n)
dl = x << 29;
fpu->fp_regs[n] = du;
fpu->fp_regs[n+1] = dl;
fpu->fp_regs[n + 1] = dl;
}
}
@ -223,67 +228,191 @@ denormal_to_double (struct sh_fpu_hard_struct *fpu, int n)
*
* Returns 1 when it's handled (should not cause exception).
*/
static int
ieee_fpe_handler (struct pt_regs *regs)
static int ieee_fpe_handler(struct pt_regs *regs)
{
unsigned short insn = *(unsigned short *) regs->pc;
unsigned short insn = *(unsigned short *)regs->pc;
unsigned short finsn;
unsigned long nextpc;
int nib[4] = {
(insn >> 12) & 0xf,
(insn >> 8) & 0xf,
(insn >> 4) & 0xf,
insn & 0xf};
insn & 0xf
};
if (nib[0] == 0xb ||
(nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb)) /* bsr & jsr */
regs->pr = regs->pc + 4;
if (nib[0] == 0xa || nib[0] == 0xb) { /* bra & bsr */
nextpc = regs->pc + 4 + ((short) ((insn & 0xfff) << 4) >> 3);
finsn = *(unsigned short *) (regs->pc + 2);
} else if (nib[0] == 0x8 && nib[1] == 0xd) { /* bt/s */
if (nib[0] == 0xb || (nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb))
regs->pr = regs->pc + 4; /* bsr & jsr */
if (nib[0] == 0xa || nib[0] == 0xb) {
/* bra & bsr */
nextpc = regs->pc + 4 + ((short)((insn & 0xfff) << 4) >> 3);
finsn = *(unsigned short *)(regs->pc + 2);
} else if (nib[0] == 0x8 && nib[1] == 0xd) {
/* bt/s */
if (regs->sr & 1)
nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1);
nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1);
else
nextpc = regs->pc + 4;
finsn = *(unsigned short *) (regs->pc + 2);
} else if (nib[0] == 0x8 && nib[1] == 0xf) { /* bf/s */
finsn = *(unsigned short *)(regs->pc + 2);
} else if (nib[0] == 0x8 && nib[1] == 0xf) {
/* bf/s */
if (regs->sr & 1)
nextpc = regs->pc + 4;
else
nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1);
finsn = *(unsigned short *) (regs->pc + 2);
nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1);
finsn = *(unsigned short *)(regs->pc + 2);
} else if (nib[0] == 0x4 && nib[3] == 0xb &&
(nib[2] == 0x0 || nib[2] == 0x2)) { /* jmp & jsr */
(nib[2] == 0x0 || nib[2] == 0x2)) {
/* jmp & jsr */
nextpc = regs->regs[nib[1]];
finsn = *(unsigned short *) (regs->pc + 2);
finsn = *(unsigned short *)(regs->pc + 2);
} else if (nib[0] == 0x0 && nib[3] == 0x3 &&
(nib[2] == 0x0 || nib[2] == 0x2)) { /* braf & bsrf */
(nib[2] == 0x0 || nib[2] == 0x2)) {
/* braf & bsrf */
nextpc = regs->pc + 4 + regs->regs[nib[1]];
finsn = *(unsigned short *) (regs->pc + 2);
} else if (insn == 0x000b) { /* rts */
finsn = *(unsigned short *)(regs->pc + 2);
} else if (insn == 0x000b) {
/* rts */
nextpc = regs->pr;
finsn = *(unsigned short *) (regs->pc + 2);
finsn = *(unsigned short *)(regs->pc + 2);
} else {
nextpc = regs->pc + instruction_size(insn);
finsn = insn;
}
if ((finsn & 0xf1ff) == 0xf0ad) { /* fcnvsd */
if ((finsn & 0xf1ff) == 0xf0ad) {
/* fcnvsd */
struct task_struct *tsk = current;
save_fpu(tsk, regs);
if ((tsk->thread.fpu.hard.fpscr & (1 << 17))) {
if ((tsk->thread.fpu.hard.fpscr & FPSCR_CAUSE_ERROR))
/* FPU error */
denormal_to_double (&tsk->thread.fpu.hard,
denormal_to_double(&tsk->thread.fpu.hard,
(finsn >> 8) & 0xf);
tsk->thread.fpu.hard.fpscr &=
~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
grab_fpu(regs);
restore_fpu(tsk);
set_tsk_thread_flag(tsk, TIF_USEDFPU);
else
return 0;
regs->pc = nextpc;
return 1;
} else if ((finsn & 0xf00f) == 0xf002) {
/* fmul */
struct task_struct *tsk = current;
int fpscr;
int n, m, prec;
unsigned int hx, hy;
n = (finsn >> 8) & 0xf;
m = (finsn >> 4) & 0xf;
hx = tsk->thread.fpu.hard.fp_regs[n];
hy = tsk->thread.fpu.hard.fp_regs[m];
fpscr = tsk->thread.fpu.hard.fpscr;
prec = fpscr & FPSCR_DBL_PRECISION;
if ((fpscr & FPSCR_CAUSE_ERROR)
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|| (hy & 0x7fffffff) < 0x00100000))) {
long long llx, lly;
/* FPU error because of denormal (doubles) */
llx = ((long long)hx << 32)
| tsk->thread.fpu.hard.fp_regs[n + 1];
lly = ((long long)hy << 32)
| tsk->thread.fpu.hard.fp_regs[m + 1];
llx = float64_mul(llx, lly);
tsk->thread.fpu.hard.fp_regs[n] = llx >> 32;
tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff;
} else if ((fpscr & FPSCR_CAUSE_ERROR)
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|| (hy & 0x7fffffff) < 0x00800000))) {
/* FPU error because of denormal (floats) */
hx = float32_mul(hx, hy);
tsk->thread.fpu.hard.fp_regs[n] = hx;
} else
force_sig(SIGFPE, tsk);
return 0;
regs->pc = nextpc;
return 1;
} else if ((finsn & 0xf00e) == 0xf000) {
/* fadd, fsub */
struct task_struct *tsk = current;
int fpscr;
int n, m, prec;
unsigned int hx, hy;
n = (finsn >> 8) & 0xf;
m = (finsn >> 4) & 0xf;
hx = tsk->thread.fpu.hard.fp_regs[n];
hy = tsk->thread.fpu.hard.fp_regs[m];
fpscr = tsk->thread.fpu.hard.fpscr;
prec = fpscr & FPSCR_DBL_PRECISION;
if ((fpscr & FPSCR_CAUSE_ERROR)
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|| (hy & 0x7fffffff) < 0x00100000))) {
long long llx, lly;
/* FPU error because of denormal (doubles) */
llx = ((long long)hx << 32)
| tsk->thread.fpu.hard.fp_regs[n + 1];
lly = ((long long)hy << 32)
| tsk->thread.fpu.hard.fp_regs[m + 1];
if ((finsn & 0xf00f) == 0xf000)
llx = float64_add(llx, lly);
else
llx = float64_sub(llx, lly);
tsk->thread.fpu.hard.fp_regs[n] = llx >> 32;
tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff;
} else if ((fpscr & FPSCR_CAUSE_ERROR)
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|| (hy & 0x7fffffff) < 0x00800000))) {
/* FPU error because of denormal (floats) */
if ((finsn & 0xf00f) == 0xf000)
hx = float32_add(hx, hy);
else
hx = float32_sub(hx, hy);
tsk->thread.fpu.hard.fp_regs[n] = hx;
} else
return 0;
regs->pc = nextpc;
return 1;
} else if ((finsn & 0xf003) == 0xf003) {
/* fdiv */
struct task_struct *tsk = current;
int fpscr;
int n, m, prec;
unsigned int hx, hy;
n = (finsn >> 8) & 0xf;
m = (finsn >> 4) & 0xf;
hx = tsk->thread.fpu.hard.fp_regs[n];
hy = tsk->thread.fpu.hard.fp_regs[m];
fpscr = tsk->thread.fpu.hard.fpscr;
prec = fpscr & FPSCR_DBL_PRECISION;
if ((fpscr & FPSCR_CAUSE_ERROR)
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|| (hy & 0x7fffffff) < 0x00100000))) {
long long llx, lly;
/* FPU error because of denormal (doubles) */
llx = ((long long)hx << 32)
| tsk->thread.fpu.hard.fp_regs[n + 1];
lly = ((long long)hy << 32)
| tsk->thread.fpu.hard.fp_regs[m + 1];
llx = float64_div(llx, lly);
tsk->thread.fpu.hard.fp_regs[n] = llx >> 32;
tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff;
} else if ((fpscr & FPSCR_CAUSE_ERROR)
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|| (hy & 0x7fffffff) < 0x00800000))) {
/* FPU error because of denormal (floats) */
hx = float32_div(hx, hy);
tsk->thread.fpu.hard.fp_regs[n] = hx;
} else
return 0;
regs->pc = nextpc;
return 1;
@ -292,16 +421,41 @@ ieee_fpe_handler (struct pt_regs *regs)
return 0;
}
void float_raise(unsigned int flags)
{
fpu_exception_flags |= flags;
}
int float_rounding_mode(void)
{
struct task_struct *tsk = current;
int roundingMode = FPSCR_ROUNDING_MODE(tsk->thread.fpu.hard.fpscr);
return roundingMode;
}
BUILD_TRAP_HANDLER(fpu_error)
{
struct task_struct *tsk = current;
TRAP_HANDLER_DECL;
if (ieee_fpe_handler(regs))
return;
regs->pc += 2;
save_fpu(tsk, regs);
fpu_exception_flags = 0;
if (ieee_fpe_handler(regs)) {
tsk->thread.fpu.hard.fpscr &=
~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
tsk->thread.fpu.hard.fpscr |= fpu_exception_flags;
/* Set the FPSCR flag as well as cause bits - simply
* replicate the cause */
tsk->thread.fpu.hard.fpscr |= (fpu_exception_flags >> 10);
grab_fpu(regs);
restore_fpu(tsk);
set_tsk_thread_flag(tsk, TIF_USEDFPU);
if ((((tsk->thread.fpu.hard.fpscr & FPSCR_ENABLE_MASK) >> 7) &
(fpu_exception_flags >> 2)) == 0) {
return;
}
}
force_sig(SIGFPE, tsk);
}

View file

@ -0,0 +1,892 @@
/*
* Floating point emulation support for subnormalised numbers on SH4
* architecture This file is derived from the SoftFloat IEC/IEEE
* Floating-point Arithmetic Package, Release 2 the original license of
* which is reproduced below.
*
* ========================================================================
*
* This C source file is part of the SoftFloat IEC/IEEE Floating-point
* Arithmetic Package, Release 2.
*
* Written by John R. Hauser. This work was made possible in part by the
* International Computer Science Institute, located at Suite 600, 1947 Center
* Street, Berkeley, California 94704. Funding was partially provided by the
* National Science Foundation under grant MIP-9311980. The original version
* of this code was written as part of a project to build a fixed-point vector
* processor in collaboration with the University of California at Berkeley,
* overseen by Profs. Nelson Morgan and John Wawrzynek. More information
* is available through the web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
* arithmetic/softfloat.html'.
*
* THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
* has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
* TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
* PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
* AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
*
* Derivative works are acceptable, even for commercial purposes, so long as
* (1) they include prominent notice that the work is derivative, and (2) they
* include prominent notice akin to these three paragraphs for those parts of
* this code that are retained.
*
* ========================================================================
*
* SH4 modifications by Ismail Dhaoui <ismail.dhaoui@st.com>
* and Kamel Khelifi <kamel.khelifi@st.com>
*/
#include <linux/kernel.h>
#include <asm/cpu/fpu.h>
#define LIT64( a ) a##LL
typedef char flag;
typedef unsigned char uint8;
typedef signed char int8;
typedef int uint16;
typedef int int16;
typedef unsigned int uint32;
typedef signed int int32;
typedef unsigned long long int bits64;
typedef signed long long int sbits64;
typedef unsigned char bits8;
typedef signed char sbits8;
typedef unsigned short int bits16;
typedef signed short int sbits16;
typedef unsigned int bits32;
typedef signed int sbits32;
typedef unsigned long long int uint64;
typedef signed long long int int64;
typedef unsigned long int float32;
typedef unsigned long long float64;
extern void float_raise(unsigned int flags); /* in fpu.c */
extern int float_rounding_mode(void); /* in fpu.c */
inline bits64 extractFloat64Frac(float64 a);
inline flag extractFloat64Sign(float64 a);
inline int16 extractFloat64Exp(float64 a);
inline int16 extractFloat32Exp(float32 a);
inline flag extractFloat32Sign(float32 a);
inline bits32 extractFloat32Frac(float32 a);
inline float64 packFloat64(flag zSign, int16 zExp, bits64 zSig);
inline void shift64RightJamming(bits64 a, int16 count, bits64 * zPtr);
inline float32 packFloat32(flag zSign, int16 zExp, bits32 zSig);
inline void shift32RightJamming(bits32 a, int16 count, bits32 * zPtr);
float64 float64_sub(float64 a, float64 b);
float32 float32_sub(float32 a, float32 b);
float32 float32_add(float32 a, float32 b);
float64 float64_add(float64 a, float64 b);
float64 float64_div(float64 a, float64 b);
float32 float32_div(float32 a, float32 b);
float32 float32_mul(float32 a, float32 b);
float64 float64_mul(float64 a, float64 b);
inline void add128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr,
bits64 * z1Ptr);
inline void sub128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr,
bits64 * z1Ptr);
inline void mul64To128(bits64 a, bits64 b, bits64 * z0Ptr, bits64 * z1Ptr);
static int8 countLeadingZeros32(bits32 a);
static int8 countLeadingZeros64(bits64 a);
static float64 normalizeRoundAndPackFloat64(flag zSign, int16 zExp,
bits64 zSig);
static float64 subFloat64Sigs(float64 a, float64 b, flag zSign);
static float64 addFloat64Sigs(float64 a, float64 b, flag zSign);
static float32 roundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig);
static float32 normalizeRoundAndPackFloat32(flag zSign, int16 zExp,
bits32 zSig);
static float64 roundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig);
static float32 subFloat32Sigs(float32 a, float32 b, flag zSign);
static float32 addFloat32Sigs(float32 a, float32 b, flag zSign);
static void normalizeFloat64Subnormal(bits64 aSig, int16 * zExpPtr,
bits64 * zSigPtr);
static bits64 estimateDiv128To64(bits64 a0, bits64 a1, bits64 b);
static void normalizeFloat32Subnormal(bits32 aSig, int16 * zExpPtr,
bits32 * zSigPtr);
inline bits64 extractFloat64Frac(float64 a)
{
return a & LIT64(0x000FFFFFFFFFFFFF);
}
inline flag extractFloat64Sign(float64 a)
{
return a >> 63;
}
inline int16 extractFloat64Exp(float64 a)
{
return (a >> 52) & 0x7FF;
}
inline int16 extractFloat32Exp(float32 a)
{
return (a >> 23) & 0xFF;
}
inline flag extractFloat32Sign(float32 a)
{
return a >> 31;
}
inline bits32 extractFloat32Frac(float32 a)
{
return a & 0x007FFFFF;
}
inline float64 packFloat64(flag zSign, int16 zExp, bits64 zSig)
{
return (((bits64) zSign) << 63) + (((bits64) zExp) << 52) + zSig;
}
inline void shift64RightJamming(bits64 a, int16 count, bits64 * zPtr)
{
bits64 z;
if (count == 0) {
z = a;
} else if (count < 64) {
z = (a >> count) | ((a << ((-count) & 63)) != 0);
} else {
z = (a != 0);
}
*zPtr = z;
}
static int8 countLeadingZeros32(bits32 a)
{
static const int8 countLeadingZerosHigh[] = {
8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
int8 shiftCount;
shiftCount = 0;
if (a < 0x10000) {
shiftCount += 16;
a <<= 16;
}
if (a < 0x1000000) {
shiftCount += 8;
a <<= 8;
}
shiftCount += countLeadingZerosHigh[a >> 24];
return shiftCount;
}
static int8 countLeadingZeros64(bits64 a)
{
int8 shiftCount;
shiftCount = 0;
if (a < ((bits64) 1) << 32) {
shiftCount += 32;
} else {
a >>= 32;
}
shiftCount += countLeadingZeros32(a);
return shiftCount;
}
static float64 normalizeRoundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig)
{
int8 shiftCount;
shiftCount = countLeadingZeros64(zSig) - 1;
return roundAndPackFloat64(zSign, zExp - shiftCount,
zSig << shiftCount);
}
static float64 subFloat64Sigs(float64 a, float64 b, flag zSign)
{
int16 aExp, bExp, zExp;
bits64 aSig, bSig, zSig;
int16 expDiff;
aSig = extractFloat64Frac(a);
aExp = extractFloat64Exp(a);
bSig = extractFloat64Frac(b);
bExp = extractFloat64Exp(b);
expDiff = aExp - bExp;
aSig <<= 10;
bSig <<= 10;
if (0 < expDiff)
goto aExpBigger;
if (expDiff < 0)
goto bExpBigger;
if (aExp == 0) {
aExp = 1;
bExp = 1;
}
if (bSig < aSig)
goto aBigger;
if (aSig < bSig)
goto bBigger;
return packFloat64(float_rounding_mode() == FPSCR_RM_ZERO, 0, 0);
bExpBigger:
if (bExp == 0x7FF) {
return packFloat64(zSign ^ 1, 0x7FF, 0);
}
if (aExp == 0) {
++expDiff;
} else {
aSig |= LIT64(0x4000000000000000);
}
shift64RightJamming(aSig, -expDiff, &aSig);
bSig |= LIT64(0x4000000000000000);
bBigger:
zSig = bSig - aSig;
zExp = bExp;
zSign ^= 1;
goto normalizeRoundAndPack;
aExpBigger:
if (aExp == 0x7FF) {
return a;
}
if (bExp == 0) {
--expDiff;
} else {
bSig |= LIT64(0x4000000000000000);
}
shift64RightJamming(bSig, expDiff, &bSig);
aSig |= LIT64(0x4000000000000000);
aBigger:
zSig = aSig - bSig;
zExp = aExp;
normalizeRoundAndPack:
--zExp;
return normalizeRoundAndPackFloat64(zSign, zExp, zSig);
}
static float64 addFloat64Sigs(float64 a, float64 b, flag zSign)
{
int16 aExp, bExp, zExp;
bits64 aSig, bSig, zSig;
int16 expDiff;
aSig = extractFloat64Frac(a);
aExp = extractFloat64Exp(a);
bSig = extractFloat64Frac(b);
bExp = extractFloat64Exp(b);
expDiff = aExp - bExp;
aSig <<= 9;
bSig <<= 9;
if (0 < expDiff) {
if (aExp == 0x7FF) {
return a;
}
if (bExp == 0) {
--expDiff;
} else {
bSig |= LIT64(0x2000000000000000);
}
shift64RightJamming(bSig, expDiff, &bSig);
zExp = aExp;
} else if (expDiff < 0) {
if (bExp == 0x7FF) {
return packFloat64(zSign, 0x7FF, 0);
}
if (aExp == 0) {
++expDiff;
} else {
aSig |= LIT64(0x2000000000000000);
}
shift64RightJamming(aSig, -expDiff, &aSig);
zExp = bExp;
} else {
if (aExp == 0x7FF) {
return a;
}
if (aExp == 0)
return packFloat64(zSign, 0, (aSig + bSig) >> 9);
zSig = LIT64(0x4000000000000000) + aSig + bSig;
zExp = aExp;
goto roundAndPack;
}
aSig |= LIT64(0x2000000000000000);
zSig = (aSig + bSig) << 1;
--zExp;
if ((sbits64) zSig < 0) {
zSig = aSig + bSig;
++zExp;
}
roundAndPack:
return roundAndPackFloat64(zSign, zExp, zSig);
}
inline float32 packFloat32(flag zSign, int16 zExp, bits32 zSig)
{
return (((bits32) zSign) << 31) + (((bits32) zExp) << 23) + zSig;
}
inline void shift32RightJamming(bits32 a, int16 count, bits32 * zPtr)
{
bits32 z;
if (count == 0) {
z = a;
} else if (count < 32) {
z = (a >> count) | ((a << ((-count) & 31)) != 0);
} else {
z = (a != 0);
}
*zPtr = z;
}
static float32 roundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig)
{
flag roundNearestEven;
int8 roundIncrement, roundBits;
flag isTiny;
/* SH4 has only 2 rounding modes - round to nearest and round to zero */
roundNearestEven = (float_rounding_mode() == FPSCR_RM_NEAREST);
roundIncrement = 0x40;
if (!roundNearestEven) {
roundIncrement = 0;
}
roundBits = zSig & 0x7F;
if (0xFD <= (bits16) zExp) {
if ((0xFD < zExp)
|| ((zExp == 0xFD)
&& ((sbits32) (zSig + roundIncrement) < 0))
) {
float_raise(FPSCR_CAUSE_OVERFLOW | FPSCR_CAUSE_INEXACT);
return packFloat32(zSign, 0xFF,
0) - (roundIncrement == 0);
}
if (zExp < 0) {
isTiny = (zExp < -1)
|| (zSig + roundIncrement < 0x80000000);
shift32RightJamming(zSig, -zExp, &zSig);
zExp = 0;
roundBits = zSig & 0x7F;
if (isTiny && roundBits)
float_raise(FPSCR_CAUSE_UNDERFLOW);
}
}
if (roundBits)
float_raise(FPSCR_CAUSE_INEXACT);
zSig = (zSig + roundIncrement) >> 7;
zSig &= ~(((roundBits ^ 0x40) == 0) & roundNearestEven);
if (zSig == 0)
zExp = 0;
return packFloat32(zSign, zExp, zSig);
}
static float32 normalizeRoundAndPackFloat32(flag zSign, int16 zExp, bits32 zSig)
{
int8 shiftCount;
shiftCount = countLeadingZeros32(zSig) - 1;
return roundAndPackFloat32(zSign, zExp - shiftCount,
zSig << shiftCount);
}
static float64 roundAndPackFloat64(flag zSign, int16 zExp, bits64 zSig)
{
flag roundNearestEven;
int16 roundIncrement, roundBits;
flag isTiny;
/* SH4 has only 2 rounding modes - round to nearest and round to zero */
roundNearestEven = (float_rounding_mode() == FPSCR_RM_NEAREST);
roundIncrement = 0x200;
if (!roundNearestEven) {
roundIncrement = 0;
}
roundBits = zSig & 0x3FF;
if (0x7FD <= (bits16) zExp) {
if ((0x7FD < zExp)
|| ((zExp == 0x7FD)
&& ((sbits64) (zSig + roundIncrement) < 0))
) {
float_raise(FPSCR_CAUSE_OVERFLOW | FPSCR_CAUSE_INEXACT);
return packFloat64(zSign, 0x7FF,
0) - (roundIncrement == 0);
}
if (zExp < 0) {
isTiny = (zExp < -1)
|| (zSig + roundIncrement <
LIT64(0x8000000000000000));
shift64RightJamming(zSig, -zExp, &zSig);
zExp = 0;
roundBits = zSig & 0x3FF;
if (isTiny && roundBits)
float_raise(FPSCR_CAUSE_UNDERFLOW);
}
}
if (roundBits)
float_raise(FPSCR_CAUSE_INEXACT);
zSig = (zSig + roundIncrement) >> 10;
zSig &= ~(((roundBits ^ 0x200) == 0) & roundNearestEven);
if (zSig == 0)
zExp = 0;
return packFloat64(zSign, zExp, zSig);
}
static float32 subFloat32Sigs(float32 a, float32 b, flag zSign)
{
int16 aExp, bExp, zExp;
bits32 aSig, bSig, zSig;
int16 expDiff;
aSig = extractFloat32Frac(a);
aExp = extractFloat32Exp(a);
bSig = extractFloat32Frac(b);
bExp = extractFloat32Exp(b);
expDiff = aExp - bExp;
aSig <<= 7;
bSig <<= 7;
if (0 < expDiff)
goto aExpBigger;
if (expDiff < 0)
goto bExpBigger;
if (aExp == 0) {
aExp = 1;
bExp = 1;
}
if (bSig < aSig)
goto aBigger;
if (aSig < bSig)
goto bBigger;
return packFloat32(float_rounding_mode() == FPSCR_RM_ZERO, 0, 0);
bExpBigger:
if (bExp == 0xFF) {
return packFloat32(zSign ^ 1, 0xFF, 0);
}
if (aExp == 0) {
++expDiff;
} else {
aSig |= 0x40000000;
}
shift32RightJamming(aSig, -expDiff, &aSig);
bSig |= 0x40000000;
bBigger:
zSig = bSig - aSig;
zExp = bExp;
zSign ^= 1;
goto normalizeRoundAndPack;
aExpBigger:
if (aExp == 0xFF) {
return a;
}
if (bExp == 0) {
--expDiff;
} else {
bSig |= 0x40000000;
}
shift32RightJamming(bSig, expDiff, &bSig);
aSig |= 0x40000000;
aBigger:
zSig = aSig - bSig;
zExp = aExp;
normalizeRoundAndPack:
--zExp;
return normalizeRoundAndPackFloat32(zSign, zExp, zSig);
}
static float32 addFloat32Sigs(float32 a, float32 b, flag zSign)
{
int16 aExp, bExp, zExp;
bits32 aSig, bSig, zSig;
int16 expDiff;
aSig = extractFloat32Frac(a);
aExp = extractFloat32Exp(a);
bSig = extractFloat32Frac(b);
bExp = extractFloat32Exp(b);
expDiff = aExp - bExp;
aSig <<= 6;
bSig <<= 6;
if (0 < expDiff) {
if (aExp == 0xFF) {
return a;
}
if (bExp == 0) {
--expDiff;
} else {
bSig |= 0x20000000;
}
shift32RightJamming(bSig, expDiff, &bSig);
zExp = aExp;
} else if (expDiff < 0) {
if (bExp == 0xFF) {
return packFloat32(zSign, 0xFF, 0);
}
if (aExp == 0) {
++expDiff;
} else {
aSig |= 0x20000000;
}
shift32RightJamming(aSig, -expDiff, &aSig);
zExp = bExp;
} else {
if (aExp == 0xFF) {
return a;
}
if (aExp == 0)
return packFloat32(zSign, 0, (aSig + bSig) >> 6);
zSig = 0x40000000 + aSig + bSig;
zExp = aExp;
goto roundAndPack;
}
aSig |= 0x20000000;
zSig = (aSig + bSig) << 1;
--zExp;
if ((sbits32) zSig < 0) {
zSig = aSig + bSig;
++zExp;
}
roundAndPack:
return roundAndPackFloat32(zSign, zExp, zSig);
}
float64 float64_sub(float64 a, float64 b)
{
flag aSign, bSign;
aSign = extractFloat64Sign(a);
bSign = extractFloat64Sign(b);
if (aSign == bSign) {
return subFloat64Sigs(a, b, aSign);
} else {
return addFloat64Sigs(a, b, aSign);
}
}
float32 float32_sub(float32 a, float32 b)
{
flag aSign, bSign;
aSign = extractFloat32Sign(a);
bSign = extractFloat32Sign(b);
if (aSign == bSign) {
return subFloat32Sigs(a, b, aSign);
} else {
return addFloat32Sigs(a, b, aSign);
}
}
float32 float32_add(float32 a, float32 b)
{
flag aSign, bSign;
aSign = extractFloat32Sign(a);
bSign = extractFloat32Sign(b);
if (aSign == bSign) {
return addFloat32Sigs(a, b, aSign);
} else {
return subFloat32Sigs(a, b, aSign);
}
}
float64 float64_add(float64 a, float64 b)
{
flag aSign, bSign;
aSign = extractFloat64Sign(a);
bSign = extractFloat64Sign(b);
if (aSign == bSign) {
return addFloat64Sigs(a, b, aSign);
} else {
return subFloat64Sigs(a, b, aSign);
}
}
static void
normalizeFloat64Subnormal(bits64 aSig, int16 * zExpPtr, bits64 * zSigPtr)
{
int8 shiftCount;
shiftCount = countLeadingZeros64(aSig) - 11;
*zSigPtr = aSig << shiftCount;
*zExpPtr = 1 - shiftCount;
}
inline void add128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr,
bits64 * z1Ptr)
{
bits64 z1;
z1 = a1 + b1;
*z1Ptr = z1;
*z0Ptr = a0 + b0 + (z1 < a1);
}
inline void
sub128(bits64 a0, bits64 a1, bits64 b0, bits64 b1, bits64 * z0Ptr,
bits64 * z1Ptr)
{
*z1Ptr = a1 - b1;
*z0Ptr = a0 - b0 - (a1 < b1);
}
static bits64 estimateDiv128To64(bits64 a0, bits64 a1, bits64 b)
{
bits64 b0, b1;
bits64 rem0, rem1, term0, term1;
bits64 z;
if (b <= a0)
return LIT64(0xFFFFFFFFFFFFFFFF);
b0 = b >> 32;
z = (b0 << 32 <= a0) ? LIT64(0xFFFFFFFF00000000) : (a0 / b0) << 32;
mul64To128(b, z, &term0, &term1);
sub128(a0, a1, term0, term1, &rem0, &rem1);
while (((sbits64) rem0) < 0) {
z -= LIT64(0x100000000);
b1 = b << 32;
add128(rem0, rem1, b0, b1, &rem0, &rem1);
}
rem0 = (rem0 << 32) | (rem1 >> 32);
z |= (b0 << 32 <= rem0) ? 0xFFFFFFFF : rem0 / b0;
return z;
}
inline void mul64To128(bits64 a, bits64 b, bits64 * z0Ptr, bits64 * z1Ptr)
{
bits32 aHigh, aLow, bHigh, bLow;
bits64 z0, zMiddleA, zMiddleB, z1;
aLow = a;
aHigh = a >> 32;
bLow = b;
bHigh = b >> 32;
z1 = ((bits64) aLow) * bLow;
zMiddleA = ((bits64) aLow) * bHigh;
zMiddleB = ((bits64) aHigh) * bLow;
z0 = ((bits64) aHigh) * bHigh;
zMiddleA += zMiddleB;
z0 += (((bits64) (zMiddleA < zMiddleB)) << 32) + (zMiddleA >> 32);
zMiddleA <<= 32;
z1 += zMiddleA;
z0 += (z1 < zMiddleA);
*z1Ptr = z1;
*z0Ptr = z0;
}
static void normalizeFloat32Subnormal(bits32 aSig, int16 * zExpPtr,
bits32 * zSigPtr)
{
int8 shiftCount;
shiftCount = countLeadingZeros32(aSig) - 8;
*zSigPtr = aSig << shiftCount;
*zExpPtr = 1 - shiftCount;
}
float64 float64_div(float64 a, float64 b)
{
flag aSign, bSign, zSign;
int16 aExp, bExp, zExp;
bits64 aSig, bSig, zSig;
bits64 rem0, rem1;
bits64 term0, term1;
aSig = extractFloat64Frac(a);
aExp = extractFloat64Exp(a);
aSign = extractFloat64Sign(a);
bSig = extractFloat64Frac(b);
bExp = extractFloat64Exp(b);
bSign = extractFloat64Sign(b);
zSign = aSign ^ bSign;
if (aExp == 0x7FF) {
if (bExp == 0x7FF) {
}
return packFloat64(zSign, 0x7FF, 0);
}
if (bExp == 0x7FF) {
return packFloat64(zSign, 0, 0);
}
if (bExp == 0) {
if (bSig == 0) {
if ((aExp | aSig) == 0) {
float_raise(FPSCR_CAUSE_INVALID);
}
return packFloat64(zSign, 0x7FF, 0);
}
normalizeFloat64Subnormal(bSig, &bExp, &bSig);
}
if (aExp == 0) {
if (aSig == 0)
return packFloat64(zSign, 0, 0);
normalizeFloat64Subnormal(aSig, &aExp, &aSig);
}
zExp = aExp - bExp + 0x3FD;
aSig = (aSig | LIT64(0x0010000000000000)) << 10;
bSig = (bSig | LIT64(0x0010000000000000)) << 11;
if (bSig <= (aSig + aSig)) {
aSig >>= 1;
++zExp;
}
zSig = estimateDiv128To64(aSig, 0, bSig);
if ((zSig & 0x1FF) <= 2) {
mul64To128(bSig, zSig, &term0, &term1);
sub128(aSig, 0, term0, term1, &rem0, &rem1);
while ((sbits64) rem0 < 0) {
--zSig;
add128(rem0, rem1, 0, bSig, &rem0, &rem1);
}
zSig |= (rem1 != 0);
}
return roundAndPackFloat64(zSign, zExp, zSig);
}
float32 float32_div(float32 a, float32 b)
{
flag aSign, bSign, zSign;
int16 aExp, bExp, zExp;
bits32 aSig, bSig, zSig;
aSig = extractFloat32Frac(a);
aExp = extractFloat32Exp(a);
aSign = extractFloat32Sign(a);
bSig = extractFloat32Frac(b);
bExp = extractFloat32Exp(b);
bSign = extractFloat32Sign(b);
zSign = aSign ^ bSign;
if (aExp == 0xFF) {
if (bExp == 0xFF) {
}
return packFloat32(zSign, 0xFF, 0);
}
if (bExp == 0xFF) {
return packFloat32(zSign, 0, 0);
}
if (bExp == 0) {
if (bSig == 0) {
return packFloat32(zSign, 0xFF, 0);
}
normalizeFloat32Subnormal(bSig, &bExp, &bSig);
}
if (aExp == 0) {
if (aSig == 0)
return packFloat32(zSign, 0, 0);
normalizeFloat32Subnormal(aSig, &aExp, &aSig);
}
zExp = aExp - bExp + 0x7D;
aSig = (aSig | 0x00800000) << 7;
bSig = (bSig | 0x00800000) << 8;
if (bSig <= (aSig + aSig)) {
aSig >>= 1;
++zExp;
}
zSig = (((bits64) aSig) << 32) / bSig;
if ((zSig & 0x3F) == 0) {
zSig |= (((bits64) bSig) * zSig != ((bits64) aSig) << 32);
}
return roundAndPackFloat32(zSign, zExp, zSig);
}
float32 float32_mul(float32 a, float32 b)
{
char aSign, bSign, zSign;
int aExp, bExp, zExp;
unsigned int aSig, bSig;
unsigned long long zSig64;
unsigned int zSig;
aSig = extractFloat32Frac(a);
aExp = extractFloat32Exp(a);
aSign = extractFloat32Sign(a);
bSig = extractFloat32Frac(b);
bExp = extractFloat32Exp(b);
bSign = extractFloat32Sign(b);
zSign = aSign ^ bSign;
if (aExp == 0) {
if (aSig == 0)
return packFloat32(zSign, 0, 0);
normalizeFloat32Subnormal(aSig, &aExp, &aSig);
}
if (bExp == 0) {
if (bSig == 0)
return packFloat32(zSign, 0, 0);
normalizeFloat32Subnormal(bSig, &bExp, &bSig);
}
if ((bExp == 0xff && bSig == 0) || (aExp == 0xff && aSig == 0))
return roundAndPackFloat32(zSign, 0xff, 0);
zExp = aExp + bExp - 0x7F;
aSig = (aSig | 0x00800000) << 7;
bSig = (bSig | 0x00800000) << 8;
shift64RightJamming(((unsigned long long)aSig) * bSig, 32, &zSig64);
zSig = zSig64;
if (0 <= (signed int)(zSig << 1)) {
zSig <<= 1;
--zExp;
}
return roundAndPackFloat32(zSign, zExp, zSig);
}
float64 float64_mul(float64 a, float64 b)
{
char aSign, bSign, zSign;
int aExp, bExp, zExp;
unsigned long long int aSig, bSig, zSig0, zSig1;
aSig = extractFloat64Frac(a);
aExp = extractFloat64Exp(a);
aSign = extractFloat64Sign(a);
bSig = extractFloat64Frac(b);
bExp = extractFloat64Exp(b);
bSign = extractFloat64Sign(b);
zSign = aSign ^ bSign;
if (aExp == 0) {
if (aSig == 0)
return packFloat64(zSign, 0, 0);
normalizeFloat64Subnormal(aSig, &aExp, &aSig);
}
if (bExp == 0) {
if (bSig == 0)
return packFloat64(zSign, 0, 0);
normalizeFloat64Subnormal(bSig, &bExp, &bSig);
}
if ((aExp == 0x7ff && aSig == 0) || (bExp == 0x7ff && bSig == 0))
return roundAndPackFloat64(zSign, 0x7ff, 0);
zExp = aExp + bExp - 0x3FF;
aSig = (aSig | 0x0010000000000000LL) << 10;
bSig = (bSig | 0x0010000000000000LL) << 11;
mul64To128(aSig, bSig, &zSig0, &zSig1);
zSig0 |= (zSig1 != 0);
if (0 <= (signed long long int)(zSig0 << 1)) {
zSig0 <<= 1;
--zExp;
}
return roundAndPackFloat64(zSign, zExp, zSig0);
}

View file

@ -0,0 +1,32 @@
/*
* linux/arch/sh/kernel/cpu/sh4/sh4_fpu.h
*
* Copyright (C) 2006 STMicroelectronics Limited
* Author: Carl Shaw <carl.shaw@st.com>
*
* May be copied or modified under the terms of the GNU General Public
* License Version 2. See linux/COPYING for more information.
*
* Definitions for SH4 FPU operations
*/
#ifndef __CPU_SH4_FPU_H
#define __CPU_SH4_FPU_H
#define FPSCR_ENABLE_MASK 0x00000f80UL
#define FPSCR_FMOV_DOUBLE (1<<1)
#define FPSCR_CAUSE_INEXACT (1<<12)
#define FPSCR_CAUSE_UNDERFLOW (1<<13)
#define FPSCR_CAUSE_OVERFLOW (1<<14)
#define FPSCR_CAUSE_DIVZERO (1<<15)
#define FPSCR_CAUSE_INVALID (1<<16)
#define FPSCR_CAUSE_ERROR (1<<17)
#define FPSCR_DBL_PRECISION (1<<19)
#define FPSCR_ROUNDING_MODE(x) ((x >> 20) & 3)
#define FPSCR_RM_NEAREST (0)
#define FPSCR_RM_ZERO (1)
#endif