Code copied from arch/powerpc/kernel/misc_32.S
Signed-off-by: Tony Breeds <t...@bakeyournoodle.com>
---
arch/powerpc/boot/div64.S | 52 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 52 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/boot/div64.S b/arch/powerpc/boot/div64.S
index d271ab5..bbcb8a4 100644
--- a/arch/powerpc/boot/div64.S
+++ b/arch/powerpc/boot/div64.S
@@ -57,3 +57,55 @@ __div64_32:
stw r8,4(r3)
mr r3,r6 # return the remainder in r3
blr
+
+/*
+ * Extended precision shifts.
+ *
+ * Updated to be valid for shift counts from 0 to 63 inclusive.
+ * -- Gabriel
+ *
+ * R3/R4 has 64 bit value
+ * R5 has shift count
+ * result in R3/R4
+ *
+ * ashrdi3: arithmetic right shift (sign propagation)
+ * lshrdi3: logical right shift
+ * ashldi3: left shift
+ */
+ .globl __ashrdi3
+__ashrdi3:
+ subfic r6,r5,32
+ srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
+ addi r7,r5,32 # could be xori, or addi with -32
+ slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
+ rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0
+ sraw r7,r3,r7 # t2 = MSW >> (count-32)
+ or r4,r4,r6 # LSW |= t1
+ slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2
+ sraw r3,r3,r5 # MSW = MSW >> count
+ or r4,r4,r7 # LSW |= t2
+ blr
+
+ .globl __ashldi3
+__ashldi3:
+ subfic r6,r5,32
+ slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count
+ addi r7,r5,32 # could be xori, or addi with -32
+ srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count)
+ slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32)
+ or r3,r3,r6 # MSW |= t1
+ slw r4,r4,r5 # LSW = LSW << count
+ or r3,r3,r7 # MSW |= t2
+ blr
+
+ .globl __lshrdi3
+__lshrdi3:
+ subfic r6,r5,32
+ srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
+ addi r7,r5,32 # could be xori, or addi with -32
+ slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
+ srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32)
+ or r4,r4,r6 # LSW |= t1
+ srw r3,r3,r5 # MSW = MSW >> count
+ or r4,r4,r7 # LSW |= t2
+ blr
--
1.7.6.4
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