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ppc/string/strcpy.s Libc-498 /dev/null
--- Libc/Libc-498/ppc/string/strcpy.s
+++ /dev/null
@@ -1,132 +0,0 @@
-/*
- * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
- */
-#define	ASSEMBLER
-#include <mach/ppc/asm.h>
-#undef	ASSEMBLER
-
-#define	__APPLE_API_PRIVATE
-#include <machine/cpu_capabilities.h>
-#undef	__APPLE_API_PRIVATE
-
-/* We use mode-independent "g" opcodes such as "srgi".  These expand
- * into word operations when targeting __ppc__, and into doubleword
- * operations when targeting __ppc64__.
- */
-#include <architecture/ppc/mode_independent_asm.h>
-
-
-// ***************
-// * S T R C P Y *
-// ***************
-//
-// char*	strcpy(const char *dst, const char *src);
-//
-// We optimize the move by doing it word parallel.  This introduces
-// a complication: if we blindly did word load/stores until finding
-// a 0, we might get a spurious page fault by touching bytes past it.
-// To avoid this, we never do a "lwz" that crosses a page boundary,
-// and never store a byte we don't have to.
-//
-// The test for 0s relies on the following inobvious but very efficient
-// word-parallel test:
-//		x =  dataWord + 0xFEFEFEFF
-//		y = ~dataWord & 0x80808080
-//		if (x & y) == 0 then no zero found
-// The test maps any non-zero byte to zero, and any zero byte to 0x80,
-// with one exception: 0x01 bytes preceeding the first zero are also
-// mapped to 0x80.
-//
-// We align the _source_, which allows us to avoid all worries about
-// spurious page faults.  Doing so is faster than aligning the dest.
-//
-// In 64-bit mode, the algorithm is doubleword parallel.
-
-        .text
-        .globl	EXT(strcpy)
-
-        .align 	5
-LEXT(strcpy)                        // char* strcpy(const char *dst, const char *src);
-        andi.	r0,r4,GPR_BYTES-1   // is source aligned?
-#if defined(__ppc__)
-        lis		r6,hi16(0xFEFEFEFF)	// start to generate 32-bit magic constants
-        lis		r7,hi16(0x80808080)
-        ori		r6,r6,lo16(0xFEFEFEFF)
-        ori		r7,r7,lo16(0x80808080)
-#else
-        ld		r6,_COMM_PAGE_MAGIC_FE(0)	// get 0xFEFEFEFE FEFEFEFF from commpage
-        ld		r7,_COMM_PAGE_MAGIC_80(0)	// get 0x80808080 80808080 from commpage
-#endif
-        mr		r9,r3				// use r9 for dest ptr (must return r3 intact)
-        beq		LwordloopEnter		// source is aligned
-        subfic	r0,r0,GPR_BYTES     // r0 <- #bytes to align source
-        mtctr	r0
-        
-// Loop over bytes.
-//		r4 = source ptr (unaligned)
-//		r6 = 0xFEFEFEFF
-//		r7 = 0x80808080
-//		r9 = dest ptr (unaligned)
-//	   ctr = byte count
-
-Lbyteloop:
-        lbz		r8,0(r4)			// r8 <- next source byte
-        addi	r4,r4,1
-        cmpwi	r8,0				// 0 ?
-        stb		r8,0(r9)			// pack into dest
-        addi	r9,r9,1
-        bdnzf	eq,Lbyteloop		// loop until (ctr==0) | (r8==0)
-        
-        bne		LwordloopEnter		// 0-byte not found, so enter word loop
-        blr							// 0-byte found, done
-        
-// Word loop: move a word or doubleword at a time until 0-byte found.
-//		r4 = source ptr (aligned)
-//		r6 = 0xFEFEFEFF
-//		r7 = 0x80808080
-//		r9 = dest ptr (unaligned)
-
-        .align	5					// align inner loop, which is 8 words ling
-Lwordloop:
-        stg		r8,0(r9)			// pack word or doubleword into destination
-        addi	r9,r9,GPR_BYTES
-LwordloopEnter:
-        lg		r8,0(r4)			// r8 <- next source word or doubleword
-        addi	r4,r4,GPR_BYTES
-        add		r10,r8,r6			// r10 <-  word + 0xFEFEFEFF
-        andc	r12,r7,r8			// r12 <- ~word & 0x80808080
-        and.	r0,r10,r12			// r0 <- nonzero iff word has a 0-byte
-        beq		Lwordloop			// loop if no 0-byte
-        
-// Found a 0-byte.  Store last word up to and including the 0, a byte at a time.
-//		r8 = last word or doubleword, known to have a 0-byte
-//		r9 = dest ptr
-
-Lstorelastbytes:
-        srgi.   r0,r8,GPR_BYTES*8-8 // shift leftmost byte into bottom so we can "stb"
-        slgi    r8,r8,8             // move on to next
-        stb		r0,0(r9)			// pack into dest
-        addi	r9,r9,1
-        bne		Lstorelastbytes		// loop until 0 stored
-        
-        blr
-