Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 135 insertions, 0 deletions

diff --git a/arch/sparc/lib/mul.S b/arch/sparc/lib/mul.S
new file mode 100644
index 000000000000..83dffbc2f62f
--- /dev/null
+++ b/arch/sparc/lib/mul.S
@@ -0,0 +1,135 @@
+/* $Id: mul.S,v 1.4 1996/09/30 02:22:32 davem Exp $
+ * mul.S:       This routine was taken from glibc-1.09 and is covered
+ *              by the GNU Library General Public License Version 2.
+ */
+
+/*
+ * Signed multiply, from Appendix E of the Sparc Version 8
+ * Architecture Manual.
+ */
+
+/*
+ * Returns %o0 * %o1 in %o1%o0 (i.e., %o1 holds the upper 32 bits of
+ * the 64-bit product).
+ *
+ * This code optimizes short (less than 13-bit) multiplies.
+ */
+
+        .globl .mul
+.mul:
+        mov     %o0, %y         ! multiplier -> Y
+        andncc  %o0, 0xfff, %g0 ! test bits 12..31
+        be      Lmul_shortway   ! if zero, can do it the short way
+         andcc  %g0, %g0, %o4   ! zero the partial product and clear N and V
+
+        /*
+         * Long multiply.  32 steps, followed by a final shift step.
+         */
+        mulscc  %o4, %o1, %o4   ! 1
+        mulscc  %o4, %o1, %o4   ! 2
+        mulscc  %o4, %o1, %o4   ! 3
+        mulscc  %o4, %o1, %o4   ! 4
+        mulscc  %o4, %o1, %o4   ! 5
+        mulscc  %o4, %o1, %o4   ! 6
+        mulscc  %o4, %o1, %o4   ! 7
+        mulscc  %o4, %o1, %o4   ! 8
+        mulscc  %o4, %o1, %o4   ! 9
+        mulscc  %o4, %o1, %o4   ! 10
+        mulscc  %o4, %o1, %o4   ! 11
+        mulscc  %o4, %o1, %o4   ! 12
+        mulscc  %o4, %o1, %o4   ! 13
+        mulscc  %o4, %o1, %o4   ! 14
+        mulscc  %o4, %o1, %o4   ! 15
+        mulscc  %o4, %o1, %o4   ! 16
+        mulscc  %o4, %o1, %o4   ! 17
+        mulscc  %o4, %o1, %o4   ! 18
+        mulscc  %o4, %o1, %o4   ! 19
+        mulscc  %o4, %o1, %o4   ! 20
+        mulscc  %o4, %o1, %o4   ! 21
+        mulscc  %o4, %o1, %o4   ! 22
+        mulscc  %o4, %o1, %o4   ! 23
+        mulscc  %o4, %o1, %o4   ! 24
+        mulscc  %o4, %o1, %o4   ! 25
+        mulscc  %o4, %o1, %o4   ! 26
+        mulscc  %o4, %o1, %o4   ! 27
+        mulscc  %o4, %o1, %o4   ! 28
+        mulscc  %o4, %o1, %o4   ! 29
+        mulscc  %o4, %o1, %o4   ! 30
+        mulscc  %o4, %o1, %o4   ! 31
+        mulscc  %o4, %o1, %o4   ! 32
+        mulscc  %o4, %g0, %o4   ! final shift
+
+        ! If %o0 was negative, the result is
+        !       (%o0 * %o1) + (%o1 << 32))
+        ! We fix that here.
+
+#if 0
+        tst     %o0
+        bge     1f
+         rd     %y, %o0
+
+        ! %o0 was indeed negative; fix upper 32 bits of result by subtracting 
+        ! %o1 (i.e., return %o4 - %o1 in %o1).
+        retl
+         sub    %o4, %o1, %o1
+
+1:
+        retl
+         mov    %o4, %o1
+#else
+        /* Faster code adapted from tege@sics.se's code for umul.S.  */
+        sra     %o0, 31, %o2    ! make mask from sign bit
+        and     %o1, %o2, %o2   ! %o2 = 0 or %o1, depending on sign of %o0
+        rd      %y, %o0         ! get lower half of product
+        retl
+         sub    %o4, %o2, %o1   ! subtract compensation 
+                                !  and put upper half in place
+#endif
+
+Lmul_shortway:
+        /*
+         * Short multiply.  12 steps, followed by a final shift step.
+         * The resulting bits are off by 12 and (32-12) = 20 bit positions,
+         * but there is no problem with %o0 being negative (unlike above).
+         */
+        mulscc  %o4, %o1, %o4   ! 1
+        mulscc  %o4, %o1, %o4   ! 2
+        mulscc  %o4, %o1, %o4   ! 3
+        mulscc  %o4, %o1, %o4   ! 4
+        mulscc  %o4, %o1, %o4   ! 5
+        mulscc  %o4, %o1, %o4   ! 6
+        mulscc  %o4, %o1, %o4   ! 7
+        mulscc  %o4, %o1, %o4   ! 8
+        mulscc  %o4, %o1, %o4   ! 9
+        mulscc  %o4, %o1, %o4   ! 10
+        mulscc  %o4, %o1, %o4   ! 11
+        mulscc  %o4, %o1, %o4   ! 12
+        mulscc  %o4, %g0, %o4   ! final shift
+
+        /*
+         *  %o4 has 20 of the bits that should be in the low part of the
+         * result; %y has the bottom 12 (as %y's top 12).  That is:
+         *
+         *        %o4               %y
+         * +----------------+----------------+
+         * | -12- |   -20-  | -12- |   -20-  |
+         * +------(---------+------)---------+
+         *  --hi-- ----low-part----
+         *
+         * The upper 12 bits of %o4 should be sign-extended to form the
+         * high part of the product (i.e., highpart = %o4 >> 20).
+         */
+
+        rd      %y, %o5
+        sll     %o4, 12, %o0    ! shift middle bits left 12
+        srl     %o5, 20, %o5    ! shift low bits right 20, zero fill at left
+        or      %o5, %o0, %o0   ! construct low part of result
+        retl
+         sra    %o4, 20, %o1    ! ... and extract high part of result
+
+        .globl  .mul_patch
+.mul_patch:
+        smul    %o0, %o1, %o0
+        retl
+         rd     %y, %o1
+        nop