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authorRalf Baechle <ralf@linux-mips.org>2014-04-30 11:21:55 +0200
committerRalf Baechle <ralf@linux-mips.org>2014-05-23 15:12:38 +0200
commit56a6473339dbd2e908cf8c6f2856d5de2bf8d15b (patch)
treea500f42c8e140cd909d0a5340474f6012c0740b4
parentaef3fb76aa1390ef864db888d06d8fcd5510df2d (diff)
MIPS: math-emu: Switch to using the MIPS rounding modes.
Previously math-emu was using the IEEE-754 constants internally. These were differing by having the constants for rounding to +/- infinity switched, so a conversion was necessary. This would be entirely avoidable if the MIPS constants were used throughout, so get rid of the bloat. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-rw-r--r--arch/mips/math-emu/cp1emu.c35
-rw-r--r--arch/mips/math-emu/dp_add.c4
-rw-r--r--arch/mips/math-emu/dp_sqrt.c8
-rw-r--r--arch/mips/math-emu/dp_sub.c4
-rw-r--r--arch/mips/math-emu/dp_tint.c8
-rw-r--r--arch/mips/math-emu/dp_tlong.c8
-rw-r--r--arch/mips/math-emu/ieee754.h7
-rw-r--r--arch/mips/math-emu/ieee754dp.c24
-rw-r--r--arch/mips/math-emu/ieee754sp.c24
-rw-r--r--arch/mips/math-emu/sp_add.c4
-rw-r--r--arch/mips/math-emu/sp_fdp.c4
-rw-r--r--arch/mips/math-emu/sp_sqrt.c4
-rw-r--r--arch/mips/math-emu/sp_sub.c4
-rw-r--r--arch/mips/math-emu/sp_tint.c8
-rw-r--r--arch/mips/math-emu/sp_tlong.c8
15 files changed, 63 insertions, 91 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index b31ce6cdb6b9..03e233223af7 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -67,21 +67,6 @@ static int fpux_emu(struct pt_regs *,
/* Determine rounding mode from the RM bits of the FCSR */
#define modeindex(v) ((v) & FPU_CSR_RM)
-/* Convert MIPS rounding mode (0..3) to IEEE library modes. */
-static const unsigned char ieee_rm[4] = {
- [FPU_CSR_RN] = IEEE754_RN,
- [FPU_CSR_RZ] = IEEE754_RZ,
- [FPU_CSR_RU] = IEEE754_RU,
- [FPU_CSR_RD] = IEEE754_RD,
-};
-/* Convert IEEE library modes to MIPS rounding mode (0..3). */
-static const unsigned char mips_rm[4] = {
- [IEEE754_RN] = FPU_CSR_RN,
- [IEEE754_RZ] = FPU_CSR_RZ,
- [IEEE754_RD] = FPU_CSR_RD,
- [IEEE754_RU] = FPU_CSR_RU,
-};
-
/* convert condition code register number to csr bit */
static const unsigned int fpucondbit[8] = {
FPU_CSR_COND0,
@@ -907,8 +892,7 @@ emul:
/* cop control register rd -> gpr[rt] */
if (MIPSInst_RD(ir) == FPCREG_CSR) {
value = ctx->fcr31;
- value = (value & ~FPU_CSR_RM) |
- mips_rm[modeindex(value)];
+ value = (value & ~FPU_CSR_RM) | modeindex(value);
pr_debug("%p gpr[%d]<-csr=%08x\n",
(void *) (xcp->cp0_epc),
MIPSInst_RT(ir), value);
@@ -939,9 +923,8 @@ emul:
* Don't write reserved bits,
* and convert to ieee library modes
*/
- ctx->fcr31 = (value &
- ~(FPU_CSR_RSVD | FPU_CSR_RM)) |
- ieee_rm[modeindex(value)];
+ ctx->fcr31 = (value & ~(FPU_CSR_RSVD | FPU_CSR_RM)) |
+ modeindex(value);
}
if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
return SIGFPE;
@@ -1515,7 +1498,7 @@ copcsr:
oldrm = ieee754_csr.rm;
SPFROMREG(fs, MIPSInst_FS(ir));
- ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
+ ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir));
rv.w = ieee754sp_tint(fs);
ieee754_csr.rm = oldrm;
rfmt = w_fmt;
@@ -1539,7 +1522,7 @@ copcsr:
oldrm = ieee754_csr.rm;
SPFROMREG(fs, MIPSInst_FS(ir));
- ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
+ ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir));
rv.l = ieee754sp_tlong(fs);
ieee754_csr.rm = oldrm;
rfmt = l_fmt;
@@ -1692,7 +1675,7 @@ dcopuop:
oldrm = ieee754_csr.rm;
DPFROMREG(fs, MIPSInst_FS(ir));
- ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
+ ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir));
rv.w = ieee754dp_tint(fs);
ieee754_csr.rm = oldrm;
rfmt = w_fmt;
@@ -1716,7 +1699,7 @@ dcopuop:
oldrm = ieee754_csr.rm;
DPFROMREG(fs, MIPSInst_FS(ir));
- ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
+ ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir));
rv.l = ieee754dp_tlong(fs);
ieee754_csr.rm = oldrm;
rfmt = l_fmt;
@@ -1926,11 +1909,7 @@ int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
* ieee754_csr. But ieee754_csr.rm is ieee
* library modes. (not mips rounding mode)
*/
- /* convert to ieee library modes */
- ieee754_csr.rm = ieee_rm[ieee754_csr.rm];
sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
- /* revert to mips rounding mode */
- ieee754_csr.rm = mips_rm[ieee754_csr.rm];
}
if (has_fpu)
diff --git a/arch/mips/math-emu/dp_add.c b/arch/mips/math-emu/dp_add.c
index 9c98b96f7287..7f64577df984 100644
--- a/arch/mips/math-emu/dp_add.c
+++ b/arch/mips/math-emu/dp_add.c
@@ -91,7 +91,7 @@ union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y)
if (xs == ys)
return x;
else
- return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
@@ -168,7 +168,7 @@ union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y)
xs = ys;
}
if (xm == 0)
- return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD);
/*
* Normalize to rounding precision.
diff --git a/arch/mips/math-emu/dp_sqrt.c b/arch/mips/math-emu/dp_sqrt.c
index 0384c094b1aa..041bbb6124bb 100644
--- a/arch/mips/math-emu/dp_sqrt.c
+++ b/arch/mips/math-emu/dp_sqrt.c
@@ -80,7 +80,7 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x)
oldcsr = ieee754_csr;
ieee754_csr.mx &= ~IEEE754_INEXACT;
ieee754_csr.sx &= ~IEEE754_INEXACT;
- ieee754_csr.rm = IEEE754_RN;
+ ieee754_csr.rm = FPU_CSR_RN;
/* adjust exponent to prevent overflow */
scalx = 0;
@@ -122,7 +122,7 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x)
/* twiddle last bit to force y correctly rounded */
/* set RZ, clear INEX flag */
- ieee754_csr.rm = IEEE754_RZ;
+ ieee754_csr.rm = FPU_CSR_RZ;
ieee754_csr.sx &= ~IEEE754_INEXACT;
/* t=x/y; ...chopped quotient, possibly inexact */
@@ -139,10 +139,10 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x)
oldcsr.sx |= IEEE754_INEXACT;
switch (oldcsr.rm) {
- case IEEE754_RU:
+ case FPU_CSR_RU:
y.bits += 1;
/* drop through */
- case IEEE754_RN:
+ case FPU_CSR_RN:
t.bits += 1;
break;
}
diff --git a/arch/mips/math-emu/dp_sub.c b/arch/mips/math-emu/dp_sub.c
index d502984df7cc..7a174029043a 100644
--- a/arch/mips/math-emu/dp_sub.c
+++ b/arch/mips/math-emu/dp_sub.c
@@ -91,7 +91,7 @@ union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y)
if (xs != ys)
return x;
else
- return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
@@ -171,7 +171,7 @@ union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y)
xs = ys;
}
if (xm == 0) {
- if (ieee754_csr.rm == IEEE754_RD)
+ if (ieee754_csr.rm == FPU_CSR_RD)
return ieee754dp_zero(1); /* round negative inf. => sign = -1 */
else
return ieee754dp_zero(0); /* other round modes => sign = 1 */
diff --git a/arch/mips/math-emu/dp_tint.c b/arch/mips/math-emu/dp_tint.c
index 972dba0baca0..6ffc336c530e 100644
--- a/arch/mips/math-emu/dp_tint.c
+++ b/arch/mips/math-emu/dp_tint.c
@@ -74,17 +74,17 @@ int ieee754dp_tint(union ieee754dp x)
to be zero */
odd = (xm & 0x1) != 0x0;
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
if (round && (sticky || odd))
xm++;
break;
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if ((round || sticky) && !xs)
xm++;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if ((round || sticky) && xs)
xm++;
break;
diff --git a/arch/mips/math-emu/dp_tlong.c b/arch/mips/math-emu/dp_tlong.c
index afaf953e576d..9cdc145b75e0 100644
--- a/arch/mips/math-emu/dp_tlong.c
+++ b/arch/mips/math-emu/dp_tlong.c
@@ -79,17 +79,17 @@ s64 ieee754dp_tlong(union ieee754dp x)
}
odd = (xm & 0x1) != 0x0;
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
if (round && (sticky || odd))
xm++;
break;
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if ((round || sticky) && !xs)
xm++;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if ((round || sticky) && xs)
xm++;
break;
diff --git a/arch/mips/math-emu/ieee754.h b/arch/mips/math-emu/ieee754.h
index 2fa939c612f6..43c4fb522ac2 100644
--- a/arch/mips/math-emu/ieee754.h
+++ b/arch/mips/math-emu/ieee754.h
@@ -126,13 +126,6 @@ enum {
#define IEEE754_CGT 0x04
#define IEEE754_CUN 0x08
-/* rounding mode
-*/
-#define IEEE754_RN 0 /* round to nearest */
-#define IEEE754_RZ 1 /* round toward zero */
-#define IEEE754_RD 2 /* round toward -Infinity */
-#define IEEE754_RU 3 /* round toward +Infinity */
-
/* "normal" comparisons
*/
static inline int ieee754sp_eq(union ieee754sp x, union ieee754sp y)
diff --git a/arch/mips/math-emu/ieee754dp.c b/arch/mips/math-emu/ieee754dp.c
index 087a6f38b149..fd134675fc2e 100644
--- a/arch/mips/math-emu/ieee754dp.c
+++ b/arch/mips/math-emu/ieee754dp.c
@@ -67,17 +67,17 @@ static u64 ieee754dp_get_rounding(int sn, u64 xm)
*/
if (xm & (DP_MBIT(3) - 1)) {
switch (ieee754_csr.rm) {
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RN:
+ case FPU_CSR_RN:
xm += 0x3 + ((xm >> 3) & 1);
/* xm += (xm&0x8)?0x4:0x3 */
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (!sn) /* ?? */
xm += 0x8;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn) /* ?? */
xm += 0x8;
break;
@@ -108,15 +108,15 @@ union ieee754dp ieee754dp_format(int sn, int xe, u64 xm)
ieee754_setcx(IEEE754_INEXACT);
switch(ieee754_csr.rm) {
- case IEEE754_RN:
- case IEEE754_RZ:
+ case FPU_CSR_RN:
+ case FPU_CSR_RZ:
return ieee754dp_zero(sn);
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (sn == 0)
return ieee754dp_min(0);
else
return ieee754dp_zero(1);
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn == 0)
return ieee754dp_zero(0);
else
@@ -172,16 +172,16 @@ union ieee754dp ieee754dp_format(int sn, int xe, u64 xm)
ieee754_setcx(IEEE754_INEXACT);
/* -O can be table indexed by (rm,sn) */
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
return ieee754dp_inf(sn);
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
return ieee754dp_max(sn);
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (sn == 0)
return ieee754dp_inf(0);
else
return ieee754dp_max(1);
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn == 0)
return ieee754dp_max(0);
else
diff --git a/arch/mips/math-emu/ieee754sp.c b/arch/mips/math-emu/ieee754sp.c
index e4cec15845b9..d348efe91445 100644
--- a/arch/mips/math-emu/ieee754sp.c
+++ b/arch/mips/math-emu/ieee754sp.c
@@ -67,17 +67,17 @@ static unsigned ieee754sp_get_rounding(int sn, unsigned xm)
*/
if (xm & (SP_MBIT(3) - 1)) {
switch (ieee754_csr.rm) {
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RN:
+ case FPU_CSR_RN:
xm += 0x3 + ((xm >> 3) & 1);
/* xm += (xm&0x8)?0x4:0x3 */
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (!sn) /* ?? */
xm += 0x8;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn) /* ?? */
xm += 0x8;
break;
@@ -108,15 +108,15 @@ union ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
ieee754_setcx(IEEE754_INEXACT);
switch(ieee754_csr.rm) {
- case IEEE754_RN:
- case IEEE754_RZ:
+ case FPU_CSR_RN:
+ case FPU_CSR_RZ:
return ieee754sp_zero(sn);
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (sn == 0)
return ieee754sp_min(0);
else
return ieee754sp_zero(1);
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn == 0)
return ieee754sp_zero(0);
else
@@ -170,16 +170,16 @@ union ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
ieee754_setcx(IEEE754_INEXACT);
/* -O can be table indexed by (rm,sn) */
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
return ieee754sp_inf(sn);
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
return ieee754sp_max(sn);
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (sn == 0)
return ieee754sp_inf(0);
else
return ieee754sp_max(1);
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn == 0)
return ieee754sp_max(0);
else
diff --git a/arch/mips/math-emu/sp_add.c b/arch/mips/math-emu/sp_add.c
index a0bc95cea1cc..2d84d460cb67 100644
--- a/arch/mips/math-emu/sp_add.c
+++ b/arch/mips/math-emu/sp_add.c
@@ -91,7 +91,7 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y)
if (xs == ys)
return x;
else
- return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
@@ -165,7 +165,7 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y)
xs = ys;
}
if (xm == 0)
- return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD);
/*
* Normalize in extended single precision
diff --git a/arch/mips/math-emu/sp_fdp.c b/arch/mips/math-emu/sp_fdp.c
index 90b9ec45e984..1b266fb16973 100644
--- a/arch/mips/math-emu/sp_fdp.c
+++ b/arch/mips/math-emu/sp_fdp.c
@@ -57,8 +57,8 @@ union ieee754sp ieee754sp_fdp(union ieee754dp x)
/* can't possibly be sp representable */
ieee754_setcx(IEEE754_UNDERFLOW);
ieee754_setcx(IEEE754_INEXACT);
- if ((ieee754_csr.rm == IEEE754_RU && !xs) ||
- (ieee754_csr.rm == IEEE754_RD && xs))
+ if ((ieee754_csr.rm == FPU_CSR_RU && !xs) ||
+ (ieee754_csr.rm == FPU_CSR_RD && xs))
return ieee754sp_mind(xs);
return ieee754sp_zero(xs);
diff --git a/arch/mips/math-emu/sp_sqrt.c b/arch/mips/math-emu/sp_sqrt.c
index 94f5befa1d70..b7c098a86f95 100644
--- a/arch/mips/math-emu/sp_sqrt.c
+++ b/arch/mips/math-emu/sp_sqrt.c
@@ -100,10 +100,10 @@ union ieee754sp ieee754sp_sqrt(union ieee754sp x)
if (ix != 0) {
ieee754_setcx(IEEE754_INEXACT);
switch (ieee754_csr.rm) {
- case IEEE754_RU:
+ case FPU_CSR_RU:
q += 2;
break;
- case IEEE754_RN:
+ case FPU_CSR_RN:
q += (q & 1);
break;
}
diff --git a/arch/mips/math-emu/sp_sub.c b/arch/mips/math-emu/sp_sub.c
index e813f4fee784..8592e49032b8 100644
--- a/arch/mips/math-emu/sp_sub.c
+++ b/arch/mips/math-emu/sp_sub.c
@@ -91,7 +91,7 @@ union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y)
if (xs != ys)
return x;
else
- return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD);
+ return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD);
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
@@ -165,7 +165,7 @@ union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y)
xs = ys;
}
if (xm == 0) {
- if (ieee754_csr.rm == IEEE754_RD)
+ if (ieee754_csr.rm == FPU_CSR_RD)
return ieee754sp_zero(1); /* round negative inf. => sign = -1 */
else
return ieee754sp_zero(0); /* other round modes => sign = 1 */
diff --git a/arch/mips/math-emu/sp_tint.c b/arch/mips/math-emu/sp_tint.c
index e1dee56ebc54..091299a31798 100644
--- a/arch/mips/math-emu/sp_tint.c
+++ b/arch/mips/math-emu/sp_tint.c
@@ -79,17 +79,17 @@ int ieee754sp_tint(union ieee754sp x)
}
odd = (xm & 0x1) != 0x0;
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
if (round && (sticky || odd))
xm++;
break;
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if ((round || sticky) && !xs)
xm++;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if ((round || sticky) && xs)
xm++;
break;
diff --git a/arch/mips/math-emu/sp_tlong.c b/arch/mips/math-emu/sp_tlong.c
index 67eff6ba9e18..9f3c742c1cea 100644
--- a/arch/mips/math-emu/sp_tlong.c
+++ b/arch/mips/math-emu/sp_tlong.c
@@ -76,17 +76,17 @@ s64 ieee754sp_tlong(union ieee754sp x)
}
odd = (xm & 0x1) != 0x0;
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
if (round && (sticky || odd))
xm++;
break;
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if ((round || sticky) && !xs)
xm++;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if ((round || sticky) && xs)
xm++;
break;