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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/lib/csum-copy.S
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!
Diffstat (limited to 'arch/x86_64/lib/csum-copy.S')
-rw-r--r--arch/x86_64/lib/csum-copy.S233
1 files changed, 233 insertions, 0 deletions
diff --git a/arch/x86_64/lib/csum-copy.S b/arch/x86_64/lib/csum-copy.S
new file mode 100644
index 00000000000..01808ec3783
--- /dev/null
+++ b/arch/x86_64/lib/csum-copy.S
@@ -0,0 +1,233 @@
+/*
+ * Copyright 2002,2003 Andi Kleen, SuSE Labs.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive
+ * for more details. No warranty for anything given at all.
+ */
+ #include <linux/linkage.h>
+ #include <asm/errno.h>
+
+/*
+ * Checksum copy with exception handling.
+ * On exceptions src_err_ptr or dst_err_ptr is set to -EFAULT and the
+ * destination is zeroed.
+ *
+ * Input
+ * rdi source
+ * rsi destination
+ * edx len (32bit)
+ * ecx sum (32bit)
+ * r8 src_err_ptr (int)
+ * r9 dst_err_ptr (int)
+ *
+ * Output
+ * eax 64bit sum. undefined in case of exception.
+ *
+ * Wrappers need to take care of valid exception sum and zeroing.
+ * They also should align source or destination to 8 bytes.
+ */
+
+ .macro source
+10:
+ .section __ex_table,"a"
+ .align 8
+ .quad 10b,.Lbad_source
+ .previous
+ .endm
+
+ .macro dest
+20:
+ .section __ex_table,"a"
+ .align 8
+ .quad 20b,.Lbad_dest
+ .previous
+ .endm
+
+ .macro ignore L=.Lignore
+30:
+ .section __ex_table,"a"
+ .align 8
+ .quad 30b,\L
+ .previous
+ .endm
+
+
+ .globl csum_partial_copy_generic
+ .p2align 4
+csum_partial_copy_generic:
+ cmpl $3*64,%edx
+ jle .Lignore
+
+.Lignore:
+ subq $7*8,%rsp
+ movq %rbx,2*8(%rsp)
+ movq %r12,3*8(%rsp)
+ movq %r14,4*8(%rsp)
+ movq %r13,5*8(%rsp)
+ movq %rbp,6*8(%rsp)
+
+ movq %r8,(%rsp)
+ movq %r9,1*8(%rsp)
+
+ movl %ecx,%eax
+ movl %edx,%ecx
+
+ xorl %r9d,%r9d
+ movq %rcx,%r12
+
+ shrq $6,%r12
+ jz .Lhandle_tail /* < 64 */
+
+ clc
+
+ /* main loop. clear in 64 byte blocks */
+ /* r9: zero, r8: temp2, rbx: temp1, rax: sum, rcx: saved length */
+ /* r11: temp3, rdx: temp4, r12 loopcnt */
+ /* r10: temp5, rbp: temp6, r14 temp7, r13 temp8 */
+ .p2align 4
+.Lloop:
+ source
+ movq (%rdi),%rbx
+ source
+ movq 8(%rdi),%r8
+ source
+ movq 16(%rdi),%r11
+ source
+ movq 24(%rdi),%rdx
+
+ source
+ movq 32(%rdi),%r10
+ source
+ movq 40(%rdi),%rbp
+ source
+ movq 48(%rdi),%r14
+ source
+ movq 56(%rdi),%r13
+
+ ignore 2f
+ prefetcht0 5*64(%rdi)
+2:
+ adcq %rbx,%rax
+ adcq %r8,%rax
+ adcq %r11,%rax
+ adcq %rdx,%rax
+ adcq %r10,%rax
+ adcq %rbp,%rax
+ adcq %r14,%rax
+ adcq %r13,%rax
+
+ decl %r12d
+
+ dest
+ movq %rbx,(%rsi)
+ dest
+ movq %r8,8(%rsi)
+ dest
+ movq %r11,16(%rsi)
+ dest
+ movq %rdx,24(%rsi)
+
+ dest
+ movq %r10,32(%rsi)
+ dest
+ movq %rbp,40(%rsi)
+ dest
+ movq %r14,48(%rsi)
+ dest
+ movq %r13,56(%rsi)
+
+3:
+
+ leaq 64(%rdi),%rdi
+ leaq 64(%rsi),%rsi
+
+ jnz .Lloop
+
+ adcq %r9,%rax
+
+ /* do last upto 56 bytes */
+.Lhandle_tail:
+ /* ecx: count */
+ movl %ecx,%r10d
+ andl $63,%ecx
+ shrl $3,%ecx
+ jz .Lfold
+ clc
+ .p2align 4
+.Lloop_8:
+ source
+ movq (%rdi),%rbx
+ adcq %rbx,%rax
+ decl %ecx
+ dest
+ movq %rbx,(%rsi)
+ leaq 8(%rsi),%rsi /* preserve carry */
+ leaq 8(%rdi),%rdi
+ jnz .Lloop_8
+ adcq %r9,%rax /* add in carry */
+
+.Lfold:
+ /* reduce checksum to 32bits */
+ movl %eax,%ebx
+ shrq $32,%rax
+ addl %ebx,%eax
+ adcl %r9d,%eax
+
+ /* do last upto 6 bytes */
+.Lhandle_7:
+ movl %r10d,%ecx
+ andl $7,%ecx
+ shrl $1,%ecx
+ jz .Lhandle_1
+ movl $2,%edx
+ xorl %ebx,%ebx
+ clc
+ .p2align 4
+.Lloop_1:
+ source
+ movw (%rdi),%bx
+ adcl %ebx,%eax
+ dest
+ decl %ecx
+ movw %bx,(%rsi)
+ leaq 2(%rdi),%rdi
+ leaq 2(%rsi),%rsi
+ jnz .Lloop_1
+ adcl %r9d,%eax /* add in carry */
+
+ /* handle last odd byte */
+.Lhandle_1:
+ testl $1,%r10d
+ jz .Lende
+ xorl %ebx,%ebx
+ source
+ movb (%rdi),%bl
+ dest
+ movb %bl,(%rsi)
+ addl %ebx,%eax
+ adcl %r9d,%eax /* carry */
+
+.Lende:
+ movq 2*8(%rsp),%rbx
+ movq 3*8(%rsp),%r12
+ movq 4*8(%rsp),%r14
+ movq 5*8(%rsp),%r13
+ movq 6*8(%rsp),%rbp
+ addq $7*8,%rsp
+ ret
+
+ /* Exception handlers. Very simple, zeroing is done in the wrappers */
+.Lbad_source:
+ movq (%rsp),%rax
+ testq %rax,%rax
+ jz .Lende
+ movl $-EFAULT,(%rax)
+ jmp .Lende
+
+.Lbad_dest:
+ movq 8(%rsp),%rax
+ testq %rax,%rax
+ jz .Lende
+ movl $-EFAULT,(%rax)
+ jmp .Lende