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reworked memset,memcpy of the cris kernel, this improves board speed by factor 20

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SVN-Revision: 7478
This commit is contained in:
John Crispin 2007-06-03 13:02:21 +00:00
parent 80b89723d2
commit 7b071f1bfc
1 changed files with 307 additions and 354 deletions
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661
target/linux/etrax-2.6/patches/cris/006-gcc-4.patch
View file

@ -1,100 +1,10 @@
diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/memset.c linux-2.6.19.2/arch/cris/arch-v10/lib/memset.c
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/memset.c 2007-05-20 01:46:35.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/memset.c 2007-05-20 01:51:47.000000000 +0200
@@ -29,224 +29,21 @@
#include <linux/types.h>
-/* No, there's no macro saying 12*4, since it is "hard" to get it into
- the asm in a good way. Thus better to expose the problem everywhere.
- */
-/* Assuming 1 cycle per dword written or read (ok, not really true), and
- one per instruction, then 43+3*(n/48-1) <= 24+24*(n/48-1)
- so n >= 45.7; n >= 0.9; we win on the first full 48-byte block to set. */
-
-#define ZERO_BLOCK_SIZE (1*12*4)
-
-void *memset(void *pdst,
- int c,
- size_t plen)
+/**
+ * memset - Fill a region of memory with the given value
+ * @s: Pointer to the start of the area.
+ * @c: The byte to fill the area with
+ * @count: The size of the area.
+ *
+ * Do not use memset() to access IO space, use memset_io() instead.
+ */
+void *memset(void *s, int c, size_t count)
{
- /* Ok. Now we want the parameters put in special registers.
- Make sure the compiler is able to make something useful of this. */
-
- register char *return_dst __asm__ ("r10") = pdst;
- register int n __asm__ ("r12") = plen;
- register int lc __asm__ ("r11") = c;
-
- /* Most apps use memset sanely. Only those memsetting about 3..4
- bytes or less get penalized compared to the generic implementation
- - and that's not really sane use. */
-
- /* Ugh. This is fragile at best. Check with newer GCC releases, if
- they compile cascaded "x |= x << 8" sanely! */
- __asm__("movu.b %0,$r13\n\t"
- "lslq 8,$r13\n\t"
- "move.b %0,$r13\n\t"
- "move.d $r13,%0\n\t"
- "lslq 16,$r13\n\t"
- "or.d $r13,%0"
- : "=r" (lc) : "0" (lc) : "r13");
-
- {
- register char *dst __asm__ ("r13") = pdst;
-
- /* This is NONPORTABLE, but since this whole routine is */
- /* grossly nonportable that doesn't matter. */
-
- if (((unsigned long) pdst & 3) != 0
- /* Oops! n=0 must be a legal call, regardless of alignment. */
- && n >= 3)
- {
- if ((unsigned long)dst & 1)
- {
- *dst = (char) lc;
- n--;
- dst++;
- }
-
- if ((unsigned long)dst & 2)
- {
- *(short *)dst = lc;
- n -= 2;
- dst += 2;
- }
- }
-
- /* Now the fun part. For the threshold value of this, check the equation
- above. */
- /* Decide which copying method to use. */
- if (n >= ZERO_BLOCK_SIZE)
- {
- /* For large copies we use 'movem' */
-
- /* It is not optimal to tell the compiler about clobbering any
- registers; that will move the saving/restoring of those registers
- to the function prologue/epilogue, and make non-movem sizes
- suboptimal.
-
- This method is not foolproof; it assumes that the "asm reg"
- declarations at the beginning of the function really are used
- here (beware: they may be moved to temporary registers).
- This way, we do not have to save/move the registers around into
- temporaries; we can safely use them straight away.
-
- If you want to check that the allocation was right; then
- check the equalities in the first comment. It should say
- "r13=r13, r12=r12, r11=r11" */
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/memset.c 2007-06-03 13:59:39.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/memset.c 2007-06-03 14:11:43.000000000 +0200
@@ -110,45 +110,28 @@
If you want to check that the allocation was right; then
check the equalities in the first comment. It should say
"r13=r13, r12=r12, r11=r11" */
- __asm__ volatile ("
- ;; Check that the following is true (same register names on
- ;; both sides of equal sign, as in r8=r8):
@ -121,7 +31,28 @@ diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/memset.c linux-2.6.19.2/arc
- ;; Now we've got this:
- ;; r13 - dst
- ;; r12 - n
-
+ __asm__ volatile (
+ "subq 11*4,$sp\n\t"
+ "movem $r10,[$sp]\n\t"
+ "move.d $r11,$r0\n\t"
+ "move.d $r11,$r1\n\t"
+ "move.d $r11,$r2\n\t"
+ "move.d $r11,$r3\n\t"
+ "move.d $r11,$r4\n\t"
+ "move.d $r11,$r5\n\t"
+ "move.d $r11,$r6\n\t"
+ "move.d $r11,$r7\n\t"
+ "move.d $r11,$r8\n\t"
+ "move.d $r11,$r9\n\t"
+ "move.d $r11,$r10\n\t"
+ "subq 12*4,$r12\n\t"
+"0:\n\t"
+ "subq 12*4,$r12\n\t"
+ "bge 0b\n\t"
+ "movem $r11,[$r13+]\n\t"
+ "addq 12*4,$r12\n\t"
+ "movem [$sp+],$r10"
- ;; Update n for the first loop
- subq 12*4,$r12
-0:
@ -134,193 +65,159 @@ diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/memset.c linux-2.6.19.2/arc
- ;; Restore registers from stack
- movem [$sp+],$r10"
-
- /* Outputs */ : "=r" (dst), "=r" (n)
- /* Inputs */ : "0" (dst), "1" (n), "r" (lc));
-
- }
-
- /* Either we directly starts copying, using dword copying
- in a loop, or we copy as much as possible with 'movem'
- and then the last block (<44 bytes) is copied here.
- This will work since 'movem' will have updated src,dst,n. */
-
- while ( n >= 16 )
- {
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- n -= 16;
- }
+ char *xs = s;
/* Outputs */ : "=r" (dst), "=r" (n)
/* Inputs */ : "0" (dst), "1" (n), "r" (lc));
@@ -161,10 +144,14 @@
- /* A switch() is definitely the fastest although it takes a LOT of code.
- * Particularly if you inline code this.
- */
- switch (n)
- {
- case 0:
- break;
- case 1:
- *(char*)dst = (char) lc;
- break;
- case 2:
- *(short*)dst = (short) lc;
- break;
- case 3:
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
- break;
- case 4:
- *((long*)dst)++ = lc;
- break;
- case 5:
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
- break;
- case 6:
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
- break;
- case 7:
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
- break;
- case 8:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- break;
- case 9:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
- break;
- case 10:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
- break;
- case 11:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
- break;
- case 12:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- break;
- case 13:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
- break;
- case 14:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
- break;
- case 15:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
- break;
- }
- }
+ while (count--)
+ *xs++ = c;
+ return s;
+}
while ( n >= 16 )
{
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
n -= 16;
}
- return return_dst; /* destination pointer. */
-} /* memset() */
@@ -182,67 +169,95 @@
*(short*)dst = (short) lc;
break;
case 3:
- *((short*)dst)++ = (short) lc;
+ *((short*)dst) = (short) lc;
+ dst+=2;
*(char*)dst = (char) lc;
break;
case 4:
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
break;
case 5:
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
*(char*)dst = (char) lc;
break;
case 6:
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
*(short*)dst = (short) lc;
break;
case 7:
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((short*)dst) = (short) lc;
+ dst+=2;
*(char*)dst = (char) lc;
break;
case 8:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
break;
case 9:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
*(char*)dst = (char) lc;
break;
case 10:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
*(short*)dst = (short) lc;
break;
case 11:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((short*)dst) = (short) lc;
+ dst+=2;
*(char*)dst = (char) lc;
break;
case 12:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
break;
case 13:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
*(char*)dst = (char) lc;
break;
case 14:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
*(short*)dst = (short) lc;
break;
case 15:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((long*)dst) = lc;
+ dst+=4;
+ *((short*)dst) = (short) lc;
+ dst+=2;
*(char*)dst = (char) lc;
break;
}
diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/string.c linux-2.6.19.2/arch/cris/arch-v10/lib/string.c
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/string.c 2007-05-20 01:46:35.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/string.c 2007-05-20 01:51:19.000000000 +0200
@@ -33,193 +33,21 @@
#include <linux/types.h>
-void *memcpy(void *pdst,
- const void *psrc,
- size_t pn)
+ /**
+ * memcpy - Copy one area of memory to another
+ * @dest: Where to copy to
+ * @src: Where to copy from
+ * @count: The size of the area.
+ *
+ * You should not use this function to access IO space, use memcpy_toio()
+ * or memcpy_fromio() instead.
+ */
+void *memcpy(void *dest, const void *src, size_t count)
{
- /* Ok. Now we want the parameters put in special registers.
- Make sure the compiler is able to make something useful of this.
- As it is now: r10 -> r13; r11 -> r11 (nop); r12 -> r12 (nop).
+ char *tmp = dest;
+ const char *s = src;
- If gcc was allright, it really would need no temporaries, and no
- stack space to save stuff on. */
-
- register void *return_dst __asm__ ("r10") = pdst;
- register char *dst __asm__ ("r13") = pdst;
- register const char *src __asm__ ("r11") = psrc;
- register int n __asm__ ("r12") = pn;
-
-
- /* When src is aligned but not dst, this makes a few extra needless
- cycles. I believe it would take as many to check that the
- re-alignment was unnecessary. */
- if (((unsigned long) dst & 3) != 0
- /* Don't align if we wouldn't copy more than a few bytes; so we
- don't have to check further for overflows. */
- && n >= 3)
- {
- if ((unsigned long) dst & 1)
- {
- n--;
- *(char*)dst = *(char*)src;
- src++;
- dst++;
- }
-
- if ((unsigned long) dst & 2)
- {
- n -= 2;
- *(short*)dst = *(short*)src;
- src += 2;
- dst += 2;
- }
- }
-
- /* Decide which copying method to use. */
- if (n >= 44*2) /* Break even between movem and
- move16 is at 38.7*2, but modulo 44. */
- {
- /* For large copies we use 'movem' */
-
- /* It is not optimal to tell the compiler about clobbering any
- registers; that will move the saving/restoring of those registers
- to the function prologue/epilogue, and make non-movem sizes
- suboptimal.
-
- This method is not foolproof; it assumes that the "asm reg"
- declarations at the beginning of the function really are used
- here (beware: they may be moved to temporary registers).
- This way, we do not have to save/move the registers around into
- temporaries; we can safely use them straight away.
-
- If you want to check that the allocation was right; then
- check the equalities in the first comment. It should say
- "r13=r13, r11=r11, r12=r12" */
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/string.c 2007-06-03 13:59:39.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/string.c 2007-06-03 14:21:02.000000000 +0200
@@ -95,37 +95,19 @@
If you want to check that the allocation was right; then
check the equalities in the first comment. It should say
"r13=r13, r11=r11, r12=r12" */
- __asm__ volatile ("
- ;; Check that the following is true (same register names on
- ;; both sides of equal sign, as in r8=r8):
@ -349,113 +246,169 @@ diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/string.c linux-2.6.19.2/arc
- ;; Restore registers from stack
- movem [$sp+],$r10"
-
- /* Outputs */ : "=r" (dst), "=r" (src), "=r" (n)
- /* Inputs */ : "0" (dst), "1" (src), "2" (n));
+ __asm__ volatile (
+ "subq 11*4,$sp\n\t"
+ "movem $r10,[$sp]\n\t"
+ "subq 44,$r12\n\t"
+"0:\n\t"
+ "movem [$r11+],$r10\n\t"
+ "subq 44,$r12\n\t"
+ "bge 0b\n\t"
+ "movem $r10,[$r13+]\n\t"
+ "addq 44,$r12\n\t"
+ "movem [$sp+],$r10\n\t"
/* Outputs */ : "=r" (dst), "=r" (src), "=r" (n)
/* Inputs */ : "0" (dst), "1" (src), "2" (n));
-
- }
-
- /* Either we directly starts copying, using dword copying
- in a loop, or we copy as much as possible with 'movem'
- and then the last block (<44 bytes) is copied here.
- This will work since 'movem' will have updated src,dst,n. */
-
- while ( n >= 16 )
- {
}
/* Either we directly starts copying, using dword copying
@@ -135,10 +117,14 @@
while ( n >= 16 )
{
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- n -= 16;
- }
-
- /* A switch() is definitely the fastest although it takes a LOT of code.
- * Particularly if you inline code this.
- */
- switch (n)
- {
- case 0:
- break;
- case 1:
- *(char*)dst = *(char*)src;
- break;
- case 2:
- *(short*)dst = *(short*)src;
- break;
- case 3:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
n -= 16;
}
@@ -156,67 +142,95 @@
*(short*)dst = *(short*)src;
break;
case 3:
- *((short*)dst)++ = *((short*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 4:
+ *((short*)dst) = *((short*)src);
+ src+=2;dst+=2;
*(char*)dst = *(char*)src;
break;
case 4:
- *((long*)dst)++ = *((long*)src)++;
- break;
- case 5:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
break;
case 5:
- *((long*)dst)++ = *((long*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 6:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(char*)dst = *(char*)src;
break;
case 6:
- *((long*)dst)++ = *((long*)src)++;
- *(short*)dst = *(short*)src;
- break;
- case 7:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(short*)dst = *(short*)src;
break;
case 7:
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 8:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((short*)dst) = *((short*)src);
+ src+=2;dst+=2;
*(char*)dst = *(char*)src;
break;
case 8:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- break;
- case 9:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
break;
case 9:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 10:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(char*)dst = *(char*)src;
break;
case 10:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *(short*)dst = *(short*)src;
- break;
- case 11:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(short*)dst = *(short*)src;
break;
case 11:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 12:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((short*)dst) = *((short*)src);
+ src+=2;dst+=2;
*(char*)dst = *(char*)src;
break;
case 12:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- break;
- case 13:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
break;
case 13:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *(char*)dst = *(char*)src;
- break;
- case 14:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(char*)dst = *(char*)src;
break;
case 14:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *(short*)dst = *(short*)src;
- break;
- case 15:
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
*(short*)dst = *(short*)src;
break;
case 15:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *(char*)dst = *(char*)src;
- break;
- }
-
- return return_dst; /* destination pointer. */
-} /* memcpy() */
+ while (count--)
+ *tmp++ = *s++;
+ return dest;
+}
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((long*)dst) = *((long*)src);
+ src+=4;dst+=4;
+ *((short*)dst) = *((short*)src);
+ src+=2;dst+=2;
*(char*)dst = *(char*)src;
break;
}
diff -urN linux-2.6.19.2.orig/arch/cris/arch-v10/lib/usercopy.c linux-2.6.19.2/arch/cris/arch-v10/lib/usercopy.c
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/usercopy.c 2007-05-16 22:11:26.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/usercopy.c 2007-05-16 23:17:41.000000000 +0200
--- linux-2.6.19.2.orig/arch/cris/arch-v10/lib/usercopy.c 2007-06-03 13:59:39.000000000 +0200
+++ linux-2.6.19.2/arch/cris/arch-v10/lib/usercopy.c 2007-06-03 14:25:55.000000000 +0200
@@ -88,63 +88,38 @@
If you want to check that the allocation was right; then
check the equalities in the first comment. It should say