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Allow multiple LO16s after a HI16 in var relocs.

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The God Eater demo uses these sometimes, and it should be safe if the
addresses match or at least overflow to the HI16 the same.
This commit is contained in:
Unknown W. Brackets 2013-06-22 11:59:35 -07:00
parent 25e8041076
commit 1f0d87afd9
1 changed files with 9 additions and 5 deletions
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14
Core/HLE/sceKernelModule.cpp
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@ -292,9 +292,13 @@ void __KernelModuleShutdown()
void WriteVarSymbol(u32 exportAddress, u32 relocAddress, u8 type)
{
// We have to post-process the HI16 part, since it might be +1 or not depending on the LO16 value.
static u32 lastHI16RelocAddress = 0;
static u32 lastHI16ExportAddress = 0;
static bool lastHI16Processed = false;
// Sometimes, there are multiple LO16s per HI16. This is okay if they match, but we need the old
// HI16 value (before our fixup) for each one.
static u32 lastHI16RelocData = 0;
static bool lastHI16Processed = true;
static u32 lastHILO16Address = 0;
u32 relocData = Memory::Read_Instruction(relocAddress);
@ -327,6 +331,7 @@ void WriteVarSymbol(u32 exportAddress, u32 relocAddress, u8 type)
// The R_MIPS_LO16 and R_MIPS_HI16 will often be *different* relocAddress values.
lastHI16RelocAddress = relocAddress;
lastHI16ExportAddress = exportAddress;
lastHI16RelocData = Memory::Read_Instruction(relocAddress);
lastHI16Processed = false;
break;
@ -338,20 +343,19 @@ void WriteVarSymbol(u32 exportAddress, u32 relocAddress, u8 type)
ERROR_LOG_REPORT(LOADER, "HI16 and LO16 imports do not match for %08x => %08x/%08x (hi16 export: %08x)", exportAddress, lastHI16RelocAddress, relocAddress, lastHI16ExportAddress);
break;
}
u32 relocDataHi = Memory::Read_Instruction(lastHI16RelocAddress);
// Sign extend the existing low value (e.g. from addiu.)
u32 full = (relocDataHi << 16) + (s16)(u16)(relocData & 0xFFFF) + exportAddress;
u32 full = (lastHI16RelocData << 16) + (s16)(u16)(relocData & 0xFFFF) + exportAddress;
if (!lastHI16Processed)
{
// The low instruction will be a signed add, which means (full & 0x8000) will subtract.
// We add 1 in that case so that it ends up the right value.
u16 high = (full >> 16) + ((full & 0x8000) ? 1 : 0);
Memory::Write_U32((relocDataHi & ~0xFFFF) | high, lastHI16RelocAddress);
Memory::Write_U32((lastHI16RelocData & ~0xFFFF) | high, lastHI16RelocAddress);
lastHI16Processed = true;
}
else if (lastHILO16Address != full)
WARN_LOG_REPORT(LOADER, "Potentially unsafe unpaired LO16 variable relocation @ %08x / %08x", lastHI16RelocAddress, relocAddress);
WARN_LOG_REPORT(LOADER, "Potentially unsafe unpaired LO16 variable relocation: hi=%08x lo=%08x / last=%08x this=%08x", lastHI16RelocAddress, relocAddress, lastHILO16Address, full);
// And then this is the low relocation, hurray.
relocData = (relocData & ~0xFFFF) | (full & 0xFFFF);