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-rw-r--r--arch/x86/lib/atomic64_386_32.S174
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/x86/lib/atomic64_386_32.S b/arch/x86/lib/atomic64_386_32.S
new file mode 100644
index 00000000000..4a5979aa688
--- /dev/null
+++ b/arch/x86/lib/atomic64_386_32.S
@@ -0,0 +1,174 @@
+/*
+ * atomic64_t for 386/486
+ *
+ * Copyright © 2010 Luca Barbieri
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/linkage.h>
+#include <asm/alternative-asm.h>
+#include <asm/dwarf2.h>
+
+/* if you want SMP support, implement these with real spinlocks */
+.macro LOCK reg
+ pushfl
+ CFI_ADJUST_CFA_OFFSET 4
+ cli
+.endm
+
+.macro UNLOCK reg
+ popfl
+ CFI_ADJUST_CFA_OFFSET -4
+.endm
+
+.macro BEGIN func reg
+$v = \reg
+
+ENTRY(atomic64_\func\()_386)
+ CFI_STARTPROC
+ LOCK $v
+
+.macro RETURN
+ UNLOCK $v
+ ret
+.endm
+
+.macro END_
+ CFI_ENDPROC
+ENDPROC(atomic64_\func\()_386)
+.purgem RETURN
+.purgem END_
+.purgem END
+.endm
+
+.macro END
+RETURN
+END_
+.endm
+.endm
+
+BEGIN read %ecx
+ movl ($v), %eax
+ movl 4($v), %edx
+END
+
+BEGIN set %esi
+ movl %ebx, ($v)
+ movl %ecx, 4($v)
+END
+
+BEGIN xchg %esi
+ movl ($v), %eax
+ movl 4($v), %edx
+ movl %ebx, ($v)
+ movl %ecx, 4($v)
+END
+
+BEGIN add %ecx
+ addl %eax, ($v)
+ adcl %edx, 4($v)
+END
+
+BEGIN add_return %ecx
+ addl ($v), %eax
+ adcl 4($v), %edx
+ movl %eax, ($v)
+ movl %edx, 4($v)
+END
+
+BEGIN sub %ecx
+ subl %eax, ($v)
+ sbbl %edx, 4($v)
+END
+
+BEGIN sub_return %ecx
+ negl %edx
+ negl %eax
+ sbbl $0, %edx
+ addl ($v), %eax
+ adcl 4($v), %edx
+ movl %eax, ($v)
+ movl %edx, 4($v)
+END
+
+BEGIN inc %esi
+ addl $1, ($v)
+ adcl $0, 4($v)
+END
+
+BEGIN inc_return %esi
+ movl ($v), %eax
+ movl 4($v), %edx
+ addl $1, %eax
+ adcl $0, %edx
+ movl %eax, ($v)
+ movl %edx, 4($v)
+END
+
+BEGIN dec %esi
+ subl $1, ($v)
+ sbbl $0, 4($v)
+END
+
+BEGIN dec_return %esi
+ movl ($v), %eax
+ movl 4($v), %edx
+ subl $1, %eax
+ sbbl $0, %edx
+ movl %eax, ($v)
+ movl %edx, 4($v)
+END
+
+BEGIN add_unless %ecx
+ addl %eax, %esi
+ adcl %edx, %edi
+ addl ($v), %eax
+ adcl 4($v), %edx
+ cmpl %eax, %esi
+ je 3f
+1:
+ movl %eax, ($v)
+ movl %edx, 4($v)
+ movl $1, %eax
+2:
+RETURN
+3:
+ cmpl %edx, %edi
+ jne 1b
+ xorl %eax, %eax
+ jmp 2b
+END_
+
+BEGIN inc_not_zero %esi
+ movl ($v), %eax
+ movl 4($v), %edx
+ testl %eax, %eax
+ je 3f
+1:
+ addl $1, %eax
+ adcl $0, %edx
+ movl %eax, ($v)
+ movl %edx, 4($v)
+ movl $1, %eax
+2:
+RETURN
+3:
+ testl %edx, %edx
+ jne 1b
+ jmp 2b
+END_
+
+BEGIN dec_if_positive %esi
+ movl ($v), %eax
+ movl 4($v), %edx
+ subl $1, %eax
+ sbbl $0, %edx
+ js 1f
+ movl %eax, ($v)
+ movl %edx, 4($v)
+1:
+END