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Fixed relocation of negative 14, 16, or 24 bit values. In case of 14

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and 24 bits the set upper bits were overwriting the upper bits of
the word at the target location (usually something like a branch
instruction).
This is the kind of bug that easily take six hours to find, especially
when working with interrupt code and being convinced that the problem
must be related.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15879 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Ingo Weinhold 2006-01-09 02:47:18 +00:00
parent 7afc7c5074
commit e525ca0a4d
1 changed files with 10 additions and 9 deletions
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19
src/system/boot/arch/ppc/elf.cpp
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@ -46,10 +46,10 @@ static inline bool
write_low24_check(addr_t P, Elf32_Word value)
{
// bits 6:29
// TODO: This check doesn't work, since negative values are allowed, too.
// if (value & 0xff000000)
// return false;
*(Elf32_Word*)P = (*(Elf32_Word*)P & 0xfc000003) | (value << 2);
if ((value & 0x3f000000) && (~value & 0x3f800000))
return false;
*(Elf32_Word*)P = (*(Elf32_Word*)P & 0xfc000003)
| ((value & 0x00ffffff) << 2);
return true;
}
@ -58,9 +58,10 @@ static inline bool
write_low14_check(addr_t P, Elf32_Word value)
{
// bits 16:29
// if (value & 0xffffc000)
// return false;
*(Elf32_Word*)P = (*(Elf32_Word*)P & 0xffff0003) | (value << 2);
if ((value & 0x3fffc000) && (~value & 0x3fffe000))
return false;
*(Elf32_Word*)P = (*(Elf32_Word*)P & 0xffff0003)
| ((value & 0x00003fff) << 2);
return true;
}
@ -77,8 +78,8 @@ static inline bool
write_half16_check(addr_t P, Elf32_Word value)
{
// bits 16:29
// if (value & 0xffff0000)
// return false;
if ((value & 0xffff0000) && (~value & 0xffff8000))
return false;
*(Elf32_Half*)P = (Elf32_Half)value;
return true;
}