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b1bac37345
Optimise 'strlen' to use microMIPS instructions and/or optimisations for binary size reduction. When the microMIPS ISA is not being used, the library function compiles to the original binary code. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
40 lines
915 B
ArmAsm
40 lines
915 B
ArmAsm
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1996, 1998, 1999, 2004 by Ralf Baechle
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* Copyright (C) 1999 Silicon Graphics, Inc.
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* Copyright (C) 2011 MIPS Technologies, Inc.
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*/
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#include <asm/asm.h>
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#include <asm/asm-offsets.h>
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#include <asm/regdef.h>
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#define EX(insn,reg,addr,handler) \
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9: insn reg, addr; \
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.section __ex_table,"a"; \
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PTR 9b, handler; \
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.previous
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/*
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* Return the size of a string (including the ending 0)
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*
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* Return 0 for error
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*/
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LEAF(__strlen_user_asm)
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LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
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and v0, a0
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bnez v0, .Lfault
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FEXPORT(__strlen_user_nocheck_asm)
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move v0, a0
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1: EX(lbu, v1, (v0), .Lfault)
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PTR_ADDIU v0, 1
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bnez v1, 1b
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PTR_SUBU v0, a0
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jr ra
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END(__strlen_user_asm)
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.Lfault: move v0, zero
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jr ra
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