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535c611ddd
Our memcpy and memcmp variants were implemented by calling the corresponding gcc builtin variants. However gcc is free to replace a call to __builtin_memcmp with a call to memcmp which, when called, will result in an endless recursion within memcmp. So let's provide asm variants and also fix the variants that are used for uncompressing the kernel image. In addition remove all other occurences of builtin function calls. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
89 lines
1.6 KiB
ArmAsm
89 lines
1.6 KiB
ArmAsm
/*
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* String handling functions.
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*
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* Copyright IBM Corp. 2012
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*/
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#include <linux/linkage.h>
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/*
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* memset implementation
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*
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* This code corresponds to the C construct below. We do distinguish
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* between clearing (c == 0) and setting a memory array (c != 0) simply
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* because nearly all memset invocations in the kernel clear memory and
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* the xc instruction is preferred in such cases.
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*
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* void *memset(void *s, int c, size_t n)
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* {
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* if (likely(c == 0))
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* return __builtin_memset(s, 0, n);
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* return __builtin_memset(s, c, n);
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* }
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*/
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ENTRY(memset)
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ltgr %r4,%r4
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bzr %r14
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ltgr %r3,%r3
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jnz .Lmemset_fill
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aghi %r4,-1
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srlg %r3,%r4,8
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ltgr %r3,%r3
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lgr %r1,%r2
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jz .Lmemset_clear_rest
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.Lmemset_clear_loop:
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xc 0(256,%r1),0(%r1)
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la %r1,256(%r1)
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brctg %r3,.Lmemset_clear_loop
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.Lmemset_clear_rest:
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larl %r3,.Lmemset_xc
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ex %r4,0(%r3)
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br %r14
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.Lmemset_fill:
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stc %r3,0(%r2)
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cghi %r4,1
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lgr %r1,%r2
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ber %r14
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aghi %r4,-2
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srlg %r3,%r4,8
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ltgr %r3,%r3
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jz .Lmemset_fill_rest
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.Lmemset_fill_loop:
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mvc 1(256,%r1),0(%r1)
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la %r1,256(%r1)
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brctg %r3,.Lmemset_fill_loop
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.Lmemset_fill_rest:
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larl %r3,.Lmemset_mvc
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ex %r4,0(%r3)
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br %r14
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.Lmemset_xc:
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xc 0(1,%r1),0(%r1)
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.Lmemset_mvc:
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mvc 1(1,%r1),0(%r1)
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/*
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* memcpy implementation
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*
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* void *memcpy(void *dest, const void *src, size_t n)
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*/
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ENTRY(memcpy)
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ltgr %r4,%r4
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bzr %r14
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aghi %r4,-1
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srlg %r5,%r4,8
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ltgr %r5,%r5
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lgr %r1,%r2
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jnz .Lmemcpy_loop
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.Lmemcpy_rest:
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larl %r5,.Lmemcpy_mvc
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ex %r4,0(%r5)
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br %r14
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.Lmemcpy_loop:
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mvc 0(256,%r1),0(%r3)
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la %r1,256(%r1)
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la %r3,256(%r3)
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brctg %r5,.Lmemcpy_loop
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j .Lmemcpy_rest
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.Lmemcpy_mvc:
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mvc 0(1,%r1),0(%r3)
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