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authorSiddhesh Poyarekar <siddhesh@redhat.com>2013-02-28 11:13:05 +0530
committerSiddhesh Poyarekar <siddhesh@redhat.com>2013-02-28 11:13:05 +0530
commit8d19fe64eeeece42639c65f9a73558f89ffbe7bb (patch)
tree10e7935a940b2b844039951217b5de36bb31a289
parentf4564ff0b6131ff0fba4bbc6d4a5340bb8b34388 (diff)
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Sync up ppc add_magnitudes and sub_magnitudes with default code
-rw-r--r--ChangeLog9
-rw-r--r--sysdeps/powerpc/powerpc32/power4/fpu/mpa.c112
-rw-r--r--sysdeps/powerpc/powerpc64/power4/fpu/mpa.c112
3 files changed, 129 insertions, 104 deletions
diff --git a/ChangeLog b/ChangeLog
index df58724364..5763107239 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2013-02-28 Siddhesh Poyarekar <siddhesh@redhat.com>
+
+ * sysdeps/powerpc/powerpc32/power4/fpu/mpa.c (add_magnitudes):
+ Use ZK to minimize writes to Z.
+ (sub_magnitudes): Simplify code a bit.
+ * sysdeps/powerpc/powerpc64/power4/fpu/mpa.c (add_magnitudes):
+ Use ZK to minimize writes to Z.
+ (sub_magnitudes): Simplify code a bit.
+
2013-02-27 Roland McGrath <roland@hack.frob.com>
* csu/gmon-start.c: Add special exception to license text.
diff --git a/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c b/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
index f30d2cb379..b22664772e 100644
--- a/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
+++ b/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
@@ -363,6 +363,7 @@ add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
{
long i, j, k;
long p2 = p;
+ double zk;
EZ = EX;
@@ -370,45 +371,54 @@ add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
j = p2 + EY - EX;
k = p2 + 1;
- if (j < 1)
+ if (__glibc_unlikely (j < 1))
{
__cpy (x, z, p);
return;
}
- else
- Z[k] = ZERO;
+
+ zk = ZERO;
for (; j > 0; i--, j--)
{
- Z[k] += X[i] + Y[j];
- if (Z[k] >= RADIX)
+ zk += X[i] + Y[j];
+ if (zk >= RADIX)
{
- Z[k] -= RADIX;
- Z[--k] = ONE;
+ Z[k--] = zk - RADIX;
+ zk = ONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
for (; i > 0; i--)
{
- Z[k] += X[i];
- if (Z[k] >= RADIX)
+ zk += X[i];
+ if (zk >= RADIX)
{
- Z[k] -= RADIX;
- Z[--k] = ONE;
+ Z[k--] = zk - RADIX;
+ zk = ONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
- if (Z[1] == ZERO)
+ if (zk == ZERO)
{
for (i = 1; i <= p2; i++)
Z[i] = Z[i + 1];
}
else
- EZ += ONE;
+ {
+ Z[1] = zk;
+ EZ += ONE;
+ }
}
/* Subtract the magnitudes of *X and *Y assuming that abs (*x) > abs (*y) > 0.
@@ -420,65 +430,63 @@ sub_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
{
long i, j, k;
long p2 = p;
+ double zk;
EZ = EX;
+ i = p2;
+ j = p2 + EY - EX;
+ k = p2;
- if (EX == EY)
+ /* Y is too small compared to X, copy X over to the result. */
+ if (__glibc_unlikely (j < 1))
{
- i = j = k = p2;
- Z[k] = Z[k + 1] = ZERO;
+ __cpy (x, z, p);
+ return;
}
- else
+
+ /* The relevant least significant digit in Y is non-zero, so we factor it in
+ to enhance accuracy. */
+ if (j < p2 && Y[j + 1] > ZERO)
{
- j = EX - EY;
- if (j > p2)
- {
- __cpy (x, z, p);
- return;
- }
- else
- {
- i = p2;
- j = p2 + 1 - j;
- k = p2;
- if (Y[j] > ZERO)
- {
- Z[k + 1] = RADIX - Y[j--];
- Z[k] = MONE;
- }
- else
- {
- Z[k + 1] = ZERO;
- Z[k] = ZERO;
- j--;
- }
- }
+ Z[k + 1] = RADIX - Y[j + 1];
+ zk = MONE;
}
+ else
+ zk = Z[k + 1] = ZERO;
+ /* Subtract and borrow. */
for (; j > 0; i--, j--)
{
- Z[k] += (X[i] - Y[j]);
- if (Z[k] < ZERO)
+ zk += (X[i] - Y[j]);
+ if (zk < ZERO)
{
- Z[k] += RADIX;
- Z[--k] = MONE;
+ Z[k--] = zk + RADIX;
+ zk = MONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
+ /* We're done with digits from Y, so it's just digits in X. */
for (; i > 0; i--)
{
- Z[k] += X[i];
- if (Z[k] < ZERO)
+ zk += X[i];
+ if (zk < ZERO)
{
- Z[k] += RADIX;
- Z[--k] = MONE;
+ Z[k--] = zk + RADIX;
+ zk = MONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
+ /* Normalize. */
for (i = 1; Z[i] == ZERO; i++);
EZ = EZ - i + 1;
for (k = 1; i <= p2 + 1;)
diff --git a/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c b/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
index f30d2cb379..b22664772e 100644
--- a/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
+++ b/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
@@ -363,6 +363,7 @@ add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
{
long i, j, k;
long p2 = p;
+ double zk;
EZ = EX;
@@ -370,45 +371,54 @@ add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
j = p2 + EY - EX;
k = p2 + 1;
- if (j < 1)
+ if (__glibc_unlikely (j < 1))
{
__cpy (x, z, p);
return;
}
- else
- Z[k] = ZERO;
+
+ zk = ZERO;
for (; j > 0; i--, j--)
{
- Z[k] += X[i] + Y[j];
- if (Z[k] >= RADIX)
+ zk += X[i] + Y[j];
+ if (zk >= RADIX)
{
- Z[k] -= RADIX;
- Z[--k] = ONE;
+ Z[k--] = zk - RADIX;
+ zk = ONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
for (; i > 0; i--)
{
- Z[k] += X[i];
- if (Z[k] >= RADIX)
+ zk += X[i];
+ if (zk >= RADIX)
{
- Z[k] -= RADIX;
- Z[--k] = ONE;
+ Z[k--] = zk - RADIX;
+ zk = ONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
- if (Z[1] == ZERO)
+ if (zk == ZERO)
{
for (i = 1; i <= p2; i++)
Z[i] = Z[i + 1];
}
else
- EZ += ONE;
+ {
+ Z[1] = zk;
+ EZ += ONE;
+ }
}
/* Subtract the magnitudes of *X and *Y assuming that abs (*x) > abs (*y) > 0.
@@ -420,65 +430,63 @@ sub_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
{
long i, j, k;
long p2 = p;
+ double zk;
EZ = EX;
+ i = p2;
+ j = p2 + EY - EX;
+ k = p2;
- if (EX == EY)
+ /* Y is too small compared to X, copy X over to the result. */
+ if (__glibc_unlikely (j < 1))
{
- i = j = k = p2;
- Z[k] = Z[k + 1] = ZERO;
+ __cpy (x, z, p);
+ return;
}
- else
+
+ /* The relevant least significant digit in Y is non-zero, so we factor it in
+ to enhance accuracy. */
+ if (j < p2 && Y[j + 1] > ZERO)
{
- j = EX - EY;
- if (j > p2)
- {
- __cpy (x, z, p);
- return;
- }
- else
- {
- i = p2;
- j = p2 + 1 - j;
- k = p2;
- if (Y[j] > ZERO)
- {
- Z[k + 1] = RADIX - Y[j--];
- Z[k] = MONE;
- }
- else
- {
- Z[k + 1] = ZERO;
- Z[k] = ZERO;
- j--;
- }
- }
+ Z[k + 1] = RADIX - Y[j + 1];
+ zk = MONE;
}
+ else
+ zk = Z[k + 1] = ZERO;
+ /* Subtract and borrow. */
for (; j > 0; i--, j--)
{
- Z[k] += (X[i] - Y[j]);
- if (Z[k] < ZERO)
+ zk += (X[i] - Y[j]);
+ if (zk < ZERO)
{
- Z[k] += RADIX;
- Z[--k] = MONE;
+ Z[k--] = zk + RADIX;
+ zk = MONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
+ /* We're done with digits from Y, so it's just digits in X. */
for (; i > 0; i--)
{
- Z[k] += X[i];
- if (Z[k] < ZERO)
+ zk += X[i];
+ if (zk < ZERO)
{
- Z[k] += RADIX;
- Z[--k] = MONE;
+ Z[k--] = zk + RADIX;
+ zk = MONE;
}
else
- Z[--k] = ZERO;
+ {
+ Z[k--] = zk;
+ zk = ZERO;
+ }
}
+ /* Normalize. */
for (i = 1; Z[i] == ZERO; i++);
EZ = EZ - i + 1;
for (k = 1; i <= p2 + 1;)